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Honório, Michelle da Silva, Roberta Vieira Nunes Pinheiro, Isabella Almeida Costa, and Paulo Sérgio Scalize. "Comparison of two methods for determining Q95 reference flow in the mouth of the surface catchment basin of the Meia Ponte river, state of Goiás, Brazil." Open Engineering 10, no. 1 (2020): 469–76. http://dx.doi.org/10.1515/eng-2020-0053.
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AbstractThe preferred data for analyzing water availability are those of historical flow series of the sources of interest; however, most Brazilian watersheds do not have sufficient fluviometric monitoring. Such cases require techniques for transposing data from one region to another, otherwise known as ‘flow regionalization’. The present work aimed to compare the method proposed by Secretaria de Meio Ambiente e Desenvolvimento Sustentável (SEMAD) of the state of Goiás with the traditional method of regionalization for determining reference flow at the mouth of the surface catchment basin of the Meia Ponte river. Data from eight fluviometric stations were used for regionalization, with the regression equations being adjusted using four different models. The result revealed that the potential and linear models performed the best, both with R2 and R2a values of 0.996 and 0.995, respectively. The relative error in the application of the potential model and of the method adopted by SEMAD were below 30%. The reference flows obtained by the two best performing methods differed, with flow determined by the traditional method being 5.93% lower than that of the SEMAD equation. Therefore, a more detailed study is recommended to determine which equation models better fit the region.
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Badano, Nicolás, Rodolfo Espina Valdés, and Eduardo Álvarez Álvarez. "Tidal current energy potential of Nalón river estuary assessment using a high precision flow model." Open Engineering 8, no. 1 (2018): 118–23. http://dx.doi.org/10.1515/eng-2018-0015.
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Abstract Obtaining energy from tide currents in onshore locations is of great interest due to the proximity to the points of consumption. This opens the door to the feasibility of new installations based on hydrokinetic microturbines even in zones of moderate speed. In this context, the accuracy of energy predictions based on hydrodynamic models is of paramount importance. This research presents a high precision methodology based on a multidimensional hydrodynamic model that is used to study the energetic potential in estuaries. Moreover, it is able to estimate the flow variations caused by microturbine installations. The paper also shows the results obtained from the application of the methodology in a study of the Nalón river mouth (Asturias, Spain).
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Lai, W. Michael, Van C. Mow, Daniel D. Sun, and Gerard A. Ateshian. "On the Electric Potentials Inside a Charged Soft Hydrated Biological Tissue: Streaming Potential Versus Diffusion Potential." Journal of Biomechanical Engineering 122, no. 4 (2000): 336–46. http://dx.doi.org/10.1115/1.1286316.
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The main objective of this study is to determine the nature of electric fields inside articular cartilage while accounting for the effects of both streaming potential and diffusion potential. Specifically, we solve two tissue mechano-electrochemical problems using the triphasic theories developed by Lai et al. (1991, ASME J. Biomech Eng., 113, pp. 245–258) and Gu et al. (1998, ASME J. Biomech. Eng., 120, pp. 169–180) (1) the steady one-dimensional permeation problem; and (2) the transient one-dimensional ramped-displacement, confined-compression, stress-relaxation problem (both in an open circuit condition) so as to be able to calculate the compressive strain, the electric potential, and the fixed charged density (FCD) inside cartilage. Our calculations show that in these two technically important problems, the diffusion potential effects compete against the flow-induced kinetic effects (streaming potential) for dominance of the electric potential inside the tissue. For softer tissues of similar FCD (i.e., lower aggregate modulus), the diffusion potential effects are enhanced when the tissue is being compressed (i.e., increasing its FCD in a nonuniform manner) either by direct compression or by drag-induced compaction; indeed, the diffusion potential effect may dominate over the streaming potential effect. The polarity of the electric potential field is in the same direction of interstitial fluid flow when streaming potential dominates, and in the opposite direction of fluid flow when diffusion potential dominates. For physiologically realistic articular cartilage material parameters, the polarity of electric potential across the tissue on the outside (surface to surface) may be opposite to the polarity across the tissue on the inside (surface to surface). Since the electromechanical signals that chodrocytes perceive in situ are the stresses, strains, pressures and the electric field generated inside the extracellular matrix when the tissue is deformed, the results from this study offer new challenges for the understanding of possible mechanisms that control chondrocyte biosyntheses. [S0148-0731(00)00604-X]
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Al-Mistarehi, Bara’ W., Ahmad H. Alomari, and Mohamad S. Al Zoubi. "Investigation of saturation flow rate using video camera at signalized intersections in Jordan." Open Engineering 11, no. 1 (2020): 216–26. http://dx.doi.org/10.1515/eng-2021-0021.
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AbstractThis study aimed to investigate a potential list of variables that may have an impact on the saturation flow rate (SFR) associated with different turning movements at signalized intersections in Jordan. Direct visits to locations were conducted, and a video camera was used. Highway capacity manual standard procedure was followed to collect the necessary traffic data. Multiple linear regression was performed to classify the factors that impact the SFR and to find the optimal model to foretell the SFR. Results showed that turning radius, presence of camera enforcement, and the speed limit are the significant factors that influence SFR for shared left- and U-turning movements (LUTM) with R2 = 76.9%. Furthermore, the presence of camera enforcement, number of lanes, speed limit, city, traffic volume, and area type are the factors that impact SFR for through movements only (THMO) with R2 = 69.6%. Also, it was found that the SFR for LUTM is 1611 vehicles per hour per lane (VPHPL),which is less than the SFR for THMO that equals to 1840 VPHPL. Calibration and validation of SFR based on local conditions can improve the efficiency of infrastructure operation and planning activities because vehicles’ characteristics and drivers’ behavior change over time.
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Strohmandl, Jan, and Zdeněk Čujan. "Risk Minimisation in Integrated Supply Chains." Open Engineering 9, no. 1 (2019): 593–99. http://dx.doi.org/10.1515/eng-2019-0082.
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AbstractIntegrated supply chains, due to their complexity, are vulnerable in relation to various types of risks, especially in the present turbulent market environment, characterised by increased demand for effectiveness of the individual logistic activities, extended customer service and decreased cost. The supply chain risks are represented by any threatening event that may unexpectedly disrupt or restrict material flow, or directly stop the scheduled logistic or manufacturing activities. Supply chain risk management includes risk identification, analysis and implementation of measures against potential risk consequences. This article describes supply chain management, risk elimination methods in the case of a technological breakdown and potential subsequent supply chain failure and application of the modified Failure Mode, Effects & Criticality Analysis (FMECA).
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Chomiuk, Bartłomiej, and Janusz Skrzypacz. "Comparison of energy parameters of a centrifugal pump with a multi-piped impeller in cooperation either with an annular channel and a spiral channel." Open Engineering 8, no. 1 (2018): 513–22. http://dx.doi.org/10.1515/eng-2018-0063.
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Abstract The article presents results of numerical analyzes, which raise a subject of influence of the cooperation the multi-piped impeller with a rationalized flow geometry of annular casing and volute casing for liquid flow through centrifugal pump and their operating parameters in the extremely low specific speed nq<10. The multi-piped impeller (patented by authors) is a major alternative to classic vane impellers. The stator type is responsible for the conversion of the kinetic energy of the liquid by the impeller outlet into potential energy, which determines the overall efficiency of the pump. Also, the article presents qualitative and quantitative verification of results obtained by computer modeling and an attempt to estimate their accuracy. The article focuses mainly on the comparison of the performance parameters of the pump with a multi-piped impeller in cooperation with two stator types with a rationalized flow geometry. Both outlet elements were tested in various configurations of constructional features. The complexity of the construction of the stator can significantly affect the manufacturing costs of pump unit. Knowledge concerning construction of hydraulic elements of centrifugal pumps working in the range of parameters corresponding specific speed (nq<10) is insufficient. As shown in the paper, the annular type casing model pump cooperating with a multi-piped impeller, designed in accordance with literature, reached far poorer operating parameters than the rational annular construction in a configuration with the same impeller.
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Scalize, Paulo Sergio, Samara Silva Soares, Andreia Cristina Fonseca Alves, et al. "Use of condensed water from air conditioning systems." Open Engineering 8, no. 1 (2018): 284–92. http://dx.doi.org/10.1515/eng-2018-0031.
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Abstract Facing the growing demand for water, discussions on environmental sustainability and conservation of this resource have become increasingly important. Among the possibilities for water conservation, air conditioning systems have potential applicability because, during their operation, water is generated via the condensation of air humidity, which is normally discarded. Thus, the objective of this work was to evaluate the water released by air conditioning equipment (condensed water) installed in the Laboratory of Water Analysis (LAnA) qualitatively and quantitatively, in order to verify its potential for use in the laboratory itself. For this, the quality of the water produced by three air conditioners was compared water quality parameters found in the literature, as well as with water produced by a distiller and an ultra-purifier, both used in the LAnA. Water quality was evaluated using physicochemical parameters (i.e. pH, electrical conductivity, resistivity, alkalinity, turbidity, apparent color and hardness) and microbiological parameters (i.e. total coliforms, Escherichia coli and heterotrophic bacteria). The average water flow produced by the three monitored air conditioners was 3.08 L/hour, which is higher than the daily consumption by the LAnA, indicating that its use would be quantitatively propitious. The physicochemical and microbiological analyses found that, condensed water can be used in the routine activities of LAnA. However, for its use as reagent-grade water, a prior treatment would be necessary, mainly due to the presence of heterotrophic bacteria.
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Elad, D., R. D. Kamm, and A. H. Shapiro. "Mathematical simulation of forced expiration." Journal of Applied Physiology 65, no. 1 (1988): 14–25. http://dx.doi.org/10.1152/jappl.1988.65.1.14.
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Flow limitation during forced expiration is simulated by a mathematical model. This model draws on the pressure-area law obtained in the accompanying paper, and the methods of analysis for one-dimensional flow in collapsible tubes developed by Shapiro (Trans. ASME J. Biomech. Eng. 99: 126-147, 1977). These methods represent an improvement over previous models in that 1) the effects of changing lung volume and of parenchymal-bronchial interdependence are simulated; 2) a more realistic representation of collapsed airways is employed; 3) a solution is obtained mouthward of the flow-limiting site by allowing for a smooth transition from sub- to supercritical flow speeds, then matching mouth pressure by imposing an elastic jump (an abrupt transition from super- to subcritical flow speeds) at the appropriate location; and 4) the effects of levels of effort (or vacuum pressure) in excess of those required to produce incipient flow limitation are examined, including the effects of potential physiological limitation.
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Mu-Mosley, Hong, Lauren B. Ostermann, Ran Zhao, et al. "Venetoclax Enhances Anti-Leukemia Activity of CD123-Specific BiTE-Secreting T-Cells in AML." Blood 136, Supplement 1 (2020): 12–13. http://dx.doi.org/10.1182/blood-2020-139625.
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Background: CD123 is frequently expressed in hematologic malignancies including AML. CD123 has been a potential immunotherapeutic target in AML due to its association with leukemic stem cells that play an essential role in disease progression and relapse. Our previous study using T-cells secreting CD123/CD3-bispecific T-cell engagers (BiTEs) (CD123-ENG T-cells) has shown activity in preclinical studies, recognizing and killing acute myeloid leukemia (AML) blasts in vitro and in vivo. CD123-ENG T-cells secrete bispecific molecules that recognize CD3 (T-cells) and CD123 (AML blasts), and are able to direct transduced T-cells and recruit bystander T-cells to kill CD123-positive blasts. Venetoclax is a BCL-2 inhibitor that can restore functional apoptosis signaling in AML cells, and has been FDA approved for the treatment of AML patients in combination with hypomethylating agents. To improve the efficacy of CD123-ENG T-cells we explored efficacy in AML by combining targeted immunotherapy (CD123-ENG T cells) with targeted inhibition of anti-apoptotic BCL-2 (venetoclax) in vitro and in vivo models of AML. Methods : CD123-ENG T-cells were generated by retroviral transduction and in vitro expansion. Non-transduced (NT) T-cells served as control. In vitro, GFP+ MOLM-13 AML cells were pretreated with venetoclax (0, 10µM, and 20µM) for 24 hours prior to co-culture with CD123-ENG or NT T-cells at an effector/target ratio of 1:10. After 16 hours, MOLM-13 AML cells were analyzed by flow cytometry and quantitated using counting beads; cytotoxicity was calculated relative to untreated MOLM-13 control. The anti-AML activity of the combination was further evaluated in a MOLM-13-luciferase xenograft AML mouse model. Leukemia progression was assessed by bioluminescence imaging. The frequency of MOLM13 AML and human T cells in periphera blod (PB) was determined by flow cytometry. Results: In vitro, we demonstrated that pretreatment of Molm13 AML cells with venetoclax enhanced the cytolytic activity of CD123-ENG T-cells compared to NT- or no T-cell controls. Interestingly, venetoclax sensitized Molm13 to CD123-ENG T-cell killing in a dose-dependent manner (Fig.1; 50%/31% killing by CD123-ENG T-cells versus 27%/14% of killing by NT T cells post pretreatment with 10µM or 20µM ventoclax, p&lt;0.001). In the Molm13 luciferase xenograft model, NSGS mice were randomized into 5 groups after AML engraftment was confirmed: 1) vehicle control, 2) Venetoclax (Ven) only, 3) CD123-ENG T-cells only, 4) Ven+CD123-ENG T-cells, 5) Ven+CD123-ENG T-cells/2-day-off Ven post T-cell infusion (Ven[2-day-off]+CD123-ENG). Venetoclax treatment (100 µg/kg daily via oral gavage) was started on day 4 post Molm13 injection, and on day 7, mice received one i.v. dose of CD123-ENG T-cells (5x106 cells/mouse). Venetoclax or CD123-ENG T-cell monotherapy reduced leukemia burden compared to the control group, and combinational treatments further inhibited leukemia progression as judged by BLI and circulating AML cells (%GFP+mCD45-/total live cells) by flow cytometry on day 15 post MOLM-13 injection: vehicle control: 19.6%; Ven+: 3.4%; CD123-ENG T-cells:1.2 %; Ven+CD123-ENG T-cells: 0.3%; Ven[2-day-off]+CD123-ENG T-cells (p&lt;0.01 Ven+ or CD123-ENG T-cells versus control; p&lt;0.001 Ven+CD123-ENG or Ven[2-day-off]+CD123-ENG T cells versus CD123-ENG T cells, n=5). The enhanced anti-AML activity of combining venetoclax and CD123-ENG T-cells translated into a significant survival benefit in comparison to single treatment alone (Fig. 2). However, while Ven+CD123-ENG and Ven[2-day-off]+CD123-ENG T-cell treated mice had a survival advantage, they had reduced circulating numbers of human CD3+ T cells on day 8 post T-cells infusion compared to mice that received CD123-ENG T-cells, indicative of potential adverse effect of venetoclax on T-cell survival in vivo. Conclusion: Our data support a concept of combining pro-apoptotic targeted and immune therapy using venetoclax and CD123-ENG T-cells in AML. While it has been reported that venetoclax does not impair T-cell functionality, more in-depth analysis of the effect of Bcl-2 inhibition on T-cell function and survival appears warranted, as it could diminish survival not only of AML blasts but also of immune cells. Disclosures Bonifant: Patents filed in the field of engineered cellular therapies: Patents & Royalties: Patents filed in the field of engineered cellular therapies. Gottschalk:Patents and patent applications in the fields of T-cell & Gene therapy for cancer: Patents & Royalties; Inmatics and Tidal: Membership on an entity's Board of Directors or advisory committees; Merck and ViraCyte: Consultancy; TESSA Therapeutics: Other: research collaboration. Velasquez:Rally! Foundation: Membership on an entity's Board of Directors or advisory committees; St. Jude: Patents & Royalties. Andreeff:Amgen: Research Funding; Daiichi-Sankyo; Jazz Pharmaceuticals; Celgene; Amgen; AstraZeneca; 6 Dimensions Capital: Consultancy; Daiichi-Sankyo; Breast Cancer Research Foundation; CPRIT; NIH/NCI; Amgen; AstraZeneca: Research Funding; Centre for Drug Research & Development; Cancer UK; NCI-CTEP; German Research Council; Leukemia Lymphoma Foundation (LLS); NCI-RDCRN (Rare Disease Clin Network); CLL Founcdation; BioLineRx; SentiBio; Aptose Biosciences, Inc: Membership on an entity's Board of Directors or advisory committees.
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Ehrich, F. F., Z. S. Spakovszky, M. Martinez-Sanchez, et al. "Unsteady Flow and Whirl-Inducing Forces in Axial-Flow Compressors: Part II—Analysis." Journal of Turbomachinery 123, no. 3 (2000): 446–52. http://dx.doi.org/10.1115/1.1370165.
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An experimental and theoretical investigation was conducted to evaluate the effects seen in axial-flow compressors when the centerline of the rotor becomes displaced from the centerline of the static structure of the engine, thus creating circumferentially nonuniform rotor-tip clearances. This displacement produces unsteady flow and creates a system of destabilizing forces, which contribute significantly to rotor whirl instability in turbomachinery. These forces were first identified by Thomas (1958. Bull. AIM, 71, No. 11/12, pp. 1039–1063.) for turbines and by Alford (1965. J. Eng. Power, Oct., pp. 333–334) for jet engines. In Part I, the results from an experimental investigation of these phenomena were presented. In this Part II, three analytic models were used to predict both the magnitude and direction of the Thomas/Alford force in its normalized form, known as the β coefficient, and the unsteady effects for the compressors tested in Part I. In addition, the effects of a whirling shaft were simulated to evaluate differences between a rotor with static offset and an actual whirling eccentric rotor. The models were also used to assess the influence of the nonaxisymmetric static pressure distribution on the rotor spool, which was not measured in the experiment. The models evaluated were (1) the two-sector parallel compressor (2SPC) model, (2) the infinite-segment-parallel-compressor (ISPC) model, and (3) the two-coupled actuator disk (2CAD) model. The results of these analyses were found to be in agreement with the experimental data in both sign and trend. Thus, the validated models provide a general means to predict the aerodynamic destabilizing forces for axial flow compressors in turbine engines. These tools have the potential to improve the design of rotordynamically stable turbomachinery.
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Mu, Hong, Huaxian Ma, Abishek Vaidya, et al. "IL15 Expressing CD123-Targeted Engager T-Cell Therapy for Adult Acute Myeloid Leukemia." Blood 132, Supplement 1 (2018): 2724. http://dx.doi.org/10.1182/blood-2018-99-116811.
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Abstract Background: CD123 is a potential immunotherapeutic target in AML due to its overexpression on leukemic stem cells that play an essential role in disease progression and relapse. Our previous study using T cells secreting CD123/CD3 bispecific engager molecules (CD123-ENG T cells) showed promising results in pediatric AML. Interleukin-15 (IL15) has emerged as a candidate immunomodulator as it enhances the cytolytic activity of CD8+ T-cells and induces long-lasting memory T cells. To improve the efficacy and persistence of CD123-ENG T-cells we developed IL-15 expressing CD123-ENG T cells. Here, we report characterization and efficacy of IL15 secreting CD123-ENG T cells in adult AML. Methods/Results: A cDNA encoding IL15 was cloned into retroviral vectors encoding CD123-ENG or CD19-ENG and the CD20 suicide gene separated by 2A sequences (CD20.2A.CD123-ENG.2A.IL15; CD20.2A.CD19-ENG.2A.IL15). ENG T cells were generated from human peripheral blood mononuclear cells (PBMCs) from normal donors by retroviral transduction and expanded in vitro. Non-transduced (NT) T cells and T cells expressing CD20 and CD123 (CD20.CD123-ENG T cells) served as controls. The transduction efficiency was between 62.81-95% (average 72%, n=3) and phenotypic analysis by flow cytometry showed reproducible CD4+, CD8+, central memory (CCR7+CD45RA-), effector memory (CCR7-CD45RA-), and naïve (CCR7+CD45RA+) T cells populations compared to NT cells. IL15 production of CD20.CD19-ENG.IL15 and CD20.CD123-ENG.IL15 T cells was confirmed by ELISA (84-154 pg/ml vs 32 and 44 pg/ml of NT and CD20.CD123-ENG T cells, p<0.01, n=3). Both, CD20.CD123-ENG and CD20.CD123-ENG.IL15 T cells recognized CD123+ AML cell lines as determined by IL2 and interferon γ (IFNγ) production (p<0.01, n=3). In contrast, NT and CD20.CD19-ENG.IL15 T cells did not, confirming specificity. In addition, CD20.CD123-ENG and CD20.CD123-ENG.IL15 T cells induced killing of only CD123-positive target cells in luciferase-and 7AAD-based cytotoxicity assay. CD20.CD123-ENG.IL15 T cells showed greater cytolytic activity than CD20.CD123-ENG T cells (p=0.0002, n=3). Finally, we evaluated the cytolytic activity of ENG T cells against two CD123+ adult AML PDX samples with clinically high-risk features (PDX#440778 [Flt3-ITD and D835 double mutations], and PDX#LFS [p53 mutant Li Fraumeni syndrome]). Both, CD20.CD123-ENG and CD20.CD123-ENG.IL15 T cells significantly killed AML PDX cells compared to NT and CD20.CD19-ENG.IL15 T cells (p<0.001, n=3). Adoptive transfer of CD20.CD123-ENG or CD20.CD123-ENG.IL15 T cells into the AML PDX#440778 mouse model revealed a significant reduction of leukemia burden in mice that received CD20.CD123-ENG.IL15 T cells 5 days post infusion (p=0.004, n=7). We are currently monitoring AML burden, frequency of infused ENG T cells, body weight and survival of treated mice, and conducting experiments in the 2nd AML PDX model. These results will be presented at the meeting. Conclusion: We demonstrate here that genetically engineering CD123-ENG T cells that express IL15 enhances their effector function resulting in improved anti-AML activity in in vitro and in vivo. The results warrant further exploration of IL15 secreting CD123-specific ENG T-cell therapy in AML. Disclosures Andreeff: Celgene: Consultancy; United Therapeutics: Patents & Royalties: GD2 inhibition in breast cancer ; SentiBio: Equity Ownership; Eutropics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Aptose: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Daiichi-Sankyo: Consultancy, Patents & Royalties: MDM2 inhibitor activity patent, Research Funding; Jazz Pharma: Consultancy; Oncoceutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Reata: Equity Ownership; Astra Zeneca: Research Funding; Oncolyze: Equity Ownership; Amgen: Consultancy, Research Funding.
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McBain, Geordie Drummond. "Three ways to compute multiport inertance." ANZIAM Journal 60 (August 26, 2019): C140—C155. http://dx.doi.org/10.21914/anziamj.v60i0.14058.
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The immediate impulse-response of a confined incompressible fluid is characterized by inertance. For a vessel with one inlet and outlet, this is a single quantity; for multiple ports the generalization is a singular reciprocal inertance matrix which acts on the port-impulses to give the corresponding inflows. The reciprocal inertance coefficients are defined by the boundary fluxes of potential flows. Green's identity converts these coefficients to domain integrals of kinetic energy. For a system discretized with finite elements, a third method is proposed for computing reciprocal inertance coefficients which requires only the stiffness matrix and the solution vectors and no numerical differentiation.
 
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Sangiolo, Dario, Noela Jordaney, Giulia Mesiano, et al. "Lentiviral Engineered T Regulatory Cells Effectively Inhibit Lymphocytes Alloreactivity across Major HLA Barriers." Blood 112, no. 11 (2008): 3515. http://dx.doi.org/10.1182/blood.v112.11.3515.3515.
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Abstract Adoptive immunotherapy strategies enrolling T regulatory cells (Tregs) might have a great potential in modulating donor T cells alloreactivity after Hematopoetic Cell Transplant (HCT). In murine models of HCT Tregs were shown to promote engraftment and contribute controlling graft versus host disease (GVHD) while still not conclusive data are available on humans. Ex-vivo engineering conventional CD4+ T cells to over-express the transcription factor FOXP3 is an intriguing approach to overcome the main difficulty of obtaining large amount of Tregs for experimental studies. Reports of retrovirus-mediated expression of FOXP3 not consistently resulted in functional Tregs while, recently, a lentivirus-mediated strategy was successfully reported to result in homogeneous and stable expression of FOXP3. Lentiviral transduced Tregs were able to suppress a polyclonal proliferation of CD4 purified lymphocytes stimulated with soluble Ab anti-CD3. In our study we generated lentiviral engineered Tregs (eng-Tregs) and investigated their inhibitory effect on unselected lymphocytes alloreactivity across major HLA barriers. Within the bulk lymphocytes population we separately tracked the suppressive influence of eng-Tregs on both CD4+ and CD8+ T cells. To obtain eng-Tregs, CD4+ T cells were purified from healthy donors and transduced with a bidirectional lentiviral vector encoding for FOXP3 and the truncated Nerve Growth Factor Receptor (ΔNGFR). Prior to transduction CD4+ cells were activated for 72 hours with IL2 (100U/ml), IL7 (20ng/ml) and soluble Ab anti-CD3 (200 ng/ml, only IL2 was added to the culture medium after transduction. The lentiviral transduction efficiency ranged from 8 to 25%, ΔNGFR+ T cells were positively selected and tested for their ability to suppress a mixed lymphocyte reaction across major HLA barriers. Effector peripheral blood mononuclear cells (PBMC) were collected from the same donors from whom eng-Tregs were generated. Effector PBMC were stained with CFSE in oder to separately track the alloreactive proliferation of both CD8+ and CD4+ subsets of T cells. Eng-Tregs were added on day 0 and HLA-mismatched irradiated PBMC were used as stimulators; both eng-Tregs and irradiated stimulators were used in a 1:1 ratio with the effectors. No cytokines or additional soluble stimulators were added to the MLR culture medium. The alloreactive proliferation of T cell subsets was determined by evaluating the logarithmic decrease of CFSE fluorescence intensity. The flow cytometry analysis on day +7 showed that alloreactive proliferation of both CD4+ and CD8+ effector cells was significantly inhibited (>75%) by the addition of eng-Tregs compared to controls. In order to rule out a possible role played by the naturally present Tregs (nat-Tregs), the effectors were depleted of the CD4+CD25high subpopulation before the MLR started. The observed alloreactive proliferation was higher after the depletion of nat-Tregs but still it could be significantly inhibited by the addition of eng-Tregs. Eng-Tregs did not significantly expanded when cultured in vitro (up to 2 weeks) with IL2 (100U/ml) but maintained a stable expression of the transgene and retained their suppressive capacity. Our data show that lentiviral engineered Tregs can efficiently down-modulate both CD4+ and CD8+ T cell alloreactivity across major HLA barriers. The observed independence from the presence of nat-Tregs might be important in future experimental HCT settings where the adoptive infusion of eng-Tregs might encounter a great variability in the number and activity of recipient’s nat-Tregs. The possibility of transducing a potentially unlimited number of CD4+ cells makes this strategy appealing for future pre-clinical studies to control GVHD in HCT settings.
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Vaidya, Abishek, Erin E. Doherty, Xiya Wu, Challice L. Bonifant, Stephen Gottschalk, and Mireya Paulina Velasquez. "Inducible MyD88 Signaling Enhances the Anti-AML Activity of BiTE-Secreting ENG T-Cells." Blood 134, Supplement_1 (2019): 4441. http://dx.doi.org/10.1182/blood-2019-125395.
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Background: Pediatric and adult acute myeloid Leukemia (AML) is a disease with poor prognosis due to its high relapse rate and treatment related mortality. Adoptive immunotherapy has the potential to improve outcomes and CD123 present a promising immunotherapy target for AML. CD123-specific engager (ENG) T-cells are cells genetically modified to secrete bispecific T-cell engagers (BiTEs) that recognize CD3+ on T-cells and CD123+ on AML. We had previously shown that inclusion of an inducible MyD88/CD40 costimulatory molecule, which is activated by a chemical inducer of dimerization (CID), improved anti-tumor effect against CD123+ targets in vitro. We now wanted to determine, which component of the costimulatory molecule is critical for the improved effector function of CD123-ENG T cells and perform in vivo studies. Methods: We generated a panel of retroviral vectors encoding CD20 as a safety switch, CD123-ENG, and an inducible costimulatory molecule consisting of a myristoylation sequence, FKBP dimerizer domains and one of three signaling costimulatory domains (MyD88 (iM) ,CD40(iC) or MyD88/CD40(iMC)). A vector specific for CD19 (CD20.CD19-ENG.iMC) and non-transduced (NT) T-cells served as controls. We genetically modified T-cells using a retroviral transduction protocol and evaluated their effector function +/- CID. We assessed the effector function of transduced T-cells using flow cytometry, ELISA and luciferase based cytotoxicity assays. We evaluated antitumor activity and persistence in vivo in a xenograft AML model. Results: We successfully generated CD20.CD123-ENG.iM, CD20.CD123-ENG.iC and CD20.CD123-ENG.iMC T-cells. Transduction efficiency ranged from 45 to 70% (±5). The immunophenotype of CD123-ENG T-cells was predominandly CD8+ effector memory. CD20.CD123-ENG T-cells expressing inducible costimulatory molecules secreted higher levels of CD123-specific BiTEs, IL2 and IFNγ in comparison to CD20.CD123-ENG T-cells when cocultured with of MOLM-13 (CD123+) and CID (p<0.005, N=3). In the presence of CID, CD20.CD123-ENG.iM or CD20.CD123-ENG.iMC T-cells were able to sequentially kill AML cells for up to 5 stimulations, as opposed to CD20.CD123 ENG, CD20.CD123 ENG.iC and NT T-cells (n=3, E:T=1:1). We evaluated the in vivo anti-AML activity of ENG T cells using an AML cell line expressing firefly luciferase (MOLM-13.ffluc) to allow for serial bioluminescence imaging. MOLM-13.ffluc bearing mice were treated with one i.v. dose of effector cells (CD20.CD123-ENG, CD20.CD123-ENG iM, CD20.CD123-ENG.iC, CD20.CD123-ENG.iMC or NT T-cells ) and 2 doses/week of CID for 2 weeks (100mg/mice, i.p.). CD20.CD123-ENG.iMC and iM T-cells had potent anti-leukemic activity, resulting in a significant survival advantage in comparison to CD20.CD123-ENG T-cells group (P<0.005, n=10 animals per group). Conclusion: We demonstrate here that inducible MyD88/CD40 costimulation significantly enhances the anti-AML activity of CD123-ENG T cells in vitro and in xenograft models. Mechanistic studies revealed that MyD88 costimulation is critical for the observed benefit. Thus, genetically modifying T-cells to express BiTEs and an inducible MyD88 costimulatory molecule may present a promising cell product for the immunotherapy of CD123+ hematological malignancies. Disclosures Bonifant: Patents filed in the field of engineered cellular therapies: Patents & Royalties: Patents filed in the field of engineered cellular therapies. Gottschalk:TESSA Therapeutics: Other: Research Collaboration; Tidal: Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria; Inmatics: Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy; MBIO: Other: St. Jude Children's Research Hospital has an existing exclusive license and ongoing partnership with Mustang Bio for the further clinical development and commercialization of this XSCID gene therapy; EMD Serono: Honoraria; ViraCyte: Consultancy; NHLBI: Research Funding; ASSISI fundation of Memphis: Research Funding; California Institute for Regenerative Medicine: Research Funding; Patents and patent applications in the fields of T-cell & Gene therapy for cancer: Patents & Royalties; America Lebanese Syrian Associated Charities: Research Funding. Velasquez:Rally! Foundation: Membership on an entity's Board of Directors or advisory committees; St. Jude: Patents & Royalties: Patent Applications in the Fields of Cell and Gene Therapy .
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Xu, Zhanxian. "A Kind of Potential Practical Sensors of Metamaterial in Electromagnetic Flaw Nondestructive Testing." Engineering 03, no. 07 (2011): 750–54. http://dx.doi.org/10.4236/eng.2011.37090.
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Railsback, Steven F., Bret C. Harvey, Sarah J. Kupferberg, Margaret M. Lang, Scott McBain, and Hart H. Welsh. "Modeling potential river management conflicts between frogs and salmonids." Canadian Journal of Fisheries and Aquatic Sciences 73, no. 5 (2016): 773–84. http://dx.doi.org/10.1139/cjfas-2015-0267.
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Management of regulated rivers for yellow-legged frogs (Rana boylii) and salmonids exemplifies potential conflicts among species adapted to different parts of the natural flow and temperature regimes. Yellow-legged frogs oviposit in rivers in spring and depend on declining flows and warming temperatures for egg and tadpole survival and growth, whereas salmonid management can include high spring flows and low-temperature reservoir releases. We built a model of how flow and temperature affect frog breeding success. Its mechanisms include adults selecting oviposition sites to balance risks of egg dewatering by decreasing flow versus scouring by high flow, temperature effects on development, habitat selection by tadpoles, and mortality via dewatering and scouring. In simulations of a regulated river managed primarily for salmonids, below-natural temperatures delayed tadpole metamorphosis into froglets, which can reduce overwinter survival. However, mitigating this impact via higher temperatures was predicted to cause adults to oviposit before spring flow releases for salmonids, which then scoured the egg masses. The relative timing of frog oviposition and high flow releases appears critical in determining conflicts between salmonid and frog management.
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Weiner, Benjamin J., and J. A. Sellwood. "Properties of the Galactic Bar from Hydrodynamical Simulations." Symposium - International Astronomical Union 169 (1996): 145–46. http://dx.doi.org/10.1017/s0074180900229628.
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It is well known that the existence of H I and CO gas at “forbidden” velocities in longitude-velocity (l–V) diagrams of the inner Galaxy (e.g. Liszt & Burton 1980, Liszt 1992) is inconsistent with circular motion in an axisymmetric potential. Gas flow in a barred potential could be consistent with the observations, however. We have compared the observations to 2-D hydrodynamical simulations of gas flows in a family of barred potentials. The gas flow pattern is very sensitive to the assumed potential, and the l–V distribution of cool gas in the inner Galaxy places strong constraints on several parameters of the Milky Way bar.
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Sanvitale, Nicoletta, Elisabeth Bowman, and Miguel Angel Cabrera. "Experimental Investigation on the Impact Dynamics of Saturated Granular Flows on Rigid Barriers." Environmental and Engineering Geoscience 27, no. 1 (2021): 127–38. http://dx.doi.org/10.2113/eeg-d-20-00033.
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ABSTRACT Debris flows involve the high-speed downslope motion of rocks, soil, and water. Their high flow velocity and high potential for impact loading make them one of the most hazardous types of gravitational mass flows. This study focused on the roles of particle size grading and degree of fluid saturation on impact behavior of fluid-saturated granular flows on a model rigid barrier in a small-scale flume. The use of a transparent debris-flow model and plane laser-induced fluorescence allowed the motion of particles and fluid within the medium to be examined and tracked using image processing. In this study, experiments were conducted on flows consisting of two uniform and one well-graded particle size gradings at three different fluid contents. The evolution of the velocity profiles, impact load, bed normal pressure, and fluid pore pressure for the different flows were measured and analyzed in order to gain a quantitative comparison of their behavior before, during, and after impact.
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Newmiller, Jeanette, Wesley Walker, William E. Fleenor, and Nicholas Pinter. "Case Study: Reconstructing the 2015 Dulcepamba River Flood Disaster." Environmental and Engineering Geoscience 26, no. 4 (2020): 393–404. http://dx.doi.org/10.2113/eeg-2337.
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ABSTRACT In March 2015, the village of San Pablo de Amalí on the Dulcepamba River in Ecuador was hit by a flood that killed three residents, destroyed five homes, and eroded several hectares of farmland. Residents asserted that the recent construction of a run-of-the-river hydroelectric facility built in the river channel directed flood flows toward the village, causing the associated damage and fatalities. We conducted a forensic hydrologic and hydraulic analysis of the catchment to assess potential causal mechanisms affecting flooding, including the construction of the hydroelectric facility. Hydrologic analysis demonstrated that the river flows produced by the March 2015 storm were equivalent to a 6-year return interval event, with a discharge of 58.6 cms, not the much more extreme 33-year return interval, 400-cms event that had been suggested in a report produced by the hydroelectric company. Hydraulic modeling determined an ∼2-m elevation surcharge of water attributable to the hydroelectric facility, suggesting that damage to the village would not have occurred without the obstruction created by debris blockage of the hydroelectric plant intake. Hydrologic modeling also quantified monthly totals of water availability in the Dulcepamba watershed, including average dry-season flow volumes. When compared to flow volumes allocated to the hydroelectric operator, the modeling indicated that the seasonal water availability in the Dulcepamba watershed is not sufficient to collectively meet the minimum in-stream environmental flow requirements, the agriculture demands from local subsistence irrigators, and the flow volumes allocated to the hydroelectric operator.
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McGuire, Luke A., Francis K. Rengers, Nina Oakley, et al. "Time Since Burning and Rainfall Characteristics Impact Post-Fire Debris-Flow Initiation and Magnitude." Environmental and Engineering Geoscience 27, no. 1 (2021): 43–56. http://dx.doi.org/10.2113/eeg-d-20-00029.
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ABSTRACT The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote elevated rates of runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Debris flows are most common in the year immediately following wildfire, but temporal changes in the likelihood and magnitude of debris flows following wildfire are not well constrained. In this study, we combine measurements of soil-hydraulic properties with vegetation survey data and numerical modeling to understand how debris-flow threats are likely to change in steep, burned watersheds during the first 3 years of recovery. We focus on documenting recovery following the 2016 Fish Fire in the San Gabriel Mountains, California, and demonstrate how a numerical model can be used to predict temporal changes in debris-flow properties and initiation thresholds. Numerical modeling suggests that the 15-minute intensity-duration (ID) threshold for debris flows in post-fire year 1 can vary from 15 to 30 mm/hr, depending on how rainfall is temporally distributed within a storm. Simulations further demonstrate that expected debris-flow volumes would be reduced by more than a factor of three following 1 year of recovery and that the 15-minute rainfall ID threshold would increase from 15 to 30 mm/hr to greater than 60 mm/hr by post-fire year 3. These results provide constraints on debris-flow thresholds within the San Gabriel Mountains and highlight the importance of considering local rainfall characteristics when using numerical models to assess debris-flow and flood potential.
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Cheng, Long, Salman Ahmed, Hans Liljestrand, et al. "Exploitation Techniques for Data-oriented Attacks with Existing and Potential Defense Approaches." ACM Transactions on Privacy and Security 24, no. 4 (2021): 1–36. http://dx.doi.org/10.1145/3462699.
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Data-oriented attacks manipulate non-control data to alter a program’s benign behavior without violating its control-flow integrity. It has been shown that such attacks can cause significant damage even in the presence of control-flow defense mechanisms. However, these threats have not been adequately addressed. In this survey article, we first map data-oriented exploits, including Data-Oriented Programming (DOP) and Block-Oriented Programming (BOP) attacks, to their assumptions/requirements and attack capabilities. Then, we compare known defenses against these attacks, in terms of approach, detection capabilities, overhead, and compatibility. It is generally believed that control flows may not be useful for data-oriented security. However, data-oriented attacks (especially DOP attacks) may generate side effects on control-flow behaviors in multiple dimensions (i.e., incompatible branch behaviors and frequency anomalies). We also characterize control-flow anomalies caused by data-oriented attacks. In the end, we discuss challenges for building deployable data-oriented defenses and open research questions.
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Campos, L. M. B. C. "On 36 Forms of the Acoustic Wave Equation in Potential Flows and Inhomogeneous Media." Applied Mechanics Reviews 60, no. 4 (2007): 149–71. http://dx.doi.org/10.1115/1.2750670.
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The starting point in the formulation of most acoustic problems is the acoustic wave equation. Those most widely used, the classical and convected wave equations, have significant restrictions, i.e., apply only to linear, nondissipative sound waves in a steady homogeneous medium at rest or in uniform motion. There are many practical situations violating these severe restrictions. In the present paper 36 distinct forms of the acoustic wave equation are derived (and numbered W1–W36), extending the classical and convected wave equations to include cases of propagation in inhomogeneous and∕or unsteady media, either at rest or in potential or vortical flows. The cases considered include: (i) linear waves, i.e., with small gradients, which imply small amplitudes, and (ii) nonlinear waves, i.e., with steep gradients, which include “ripples” (large gradients with small amplitude) or large amplitude waves. Only nondissipative waves are considered, i.e., excluding and dissipation by shear and bulk viscosity and thermal conduction. Consideration is given to propagation in homogeneous media and inhomogeneous media, which are homentropic (i.e., have uniform entropy) or isentropic (i.e., entropy is conserved along streamlines), excluding nonisentropic (e.g., dissipative); unsteady media are also considered. The medium may be at rest, in uniform motion, or it may be a nonuniform and∕or unsteady mean flow, including: (i) potential mean flow, of low Mach number (i.e., incompressible mean state) or of high-speed (i.e., inhomogeneous compressible mean flow); (ii) quasi-one-dimensional propagation in ducts of varying cross section, including horns without mean flow and nozzles with low or high Mach number mean flow; or (iii) unidirectional sheared mean flow, in the plane, in space or axisymmetric. Other types of vortical mean flows, e.g., axisymmetric swirling mean flow, possibly combined with shear, are not considered in the present paper (and are left to follow-up work together with dissipative and other cases). The 36 wave equations are derived either by elimination among the general equations of fluid mechanics or from an acoustic variational principle, with both methods being used in a number of cases as cross-checks. Although the 36 forms of the acoustic wave equation do not cover all possible combinations of the three effects of (i) nonlinearity in (ii) inhomogeneous and unsteady and (iii) nonuniformly moving media, they do include each effect in isolation and a variety of combinations of multiple effects. Altogether they provide a useful variety of extensions of the classical (and convected) wave equations, which are used widely in the literature, in spite of being restricted to linear, nondissipative sound waves in an homogeneous steady medium at rest (or in uniform motion). There are many applications for which the classical and convected wave equations are poor approximations, and more general forms of the acoustic wave equation provide more satisfactory models. Numerous examples of these applications are given at the end of each written section. There are 240 references cited in this review article.
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Nordey, Thibault, Mathieu Léchaudel, and Michel Génard. "The decline in xylem flow to mango fruit at the end of its development is related to the appearance of embolism in the fruit pedicel." Functional Plant Biology 42, no. 7 (2015): 668. http://dx.doi.org/10.1071/fp14306.
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The decline in xylem flow during the late growth stage in most fruits may be due either to a decrease in the water potential gradient between the stem bearing the fruit and the fruit tissues or to a decrease in the hydraulic conductivity of xylem vessels, or both. In this study, we analysed changes in xylem flows to the mango Mangifera indica L. fruit during its development to identify the sources of variation by measuring changes in the water potential gradient and in the hydraulic properties of the fruit pedicel. The variations in xylem and transpiration flows were estimated at several stages of mango fruit development from the daily changes in the fresh mass of detached and girdled fruits on branches. The water potential gradient was estimated by monitoring the diurnal water potential in the stem and fruit. The hydraulic properties of the fruit pedicel were estimated using a flow meter. The results indicated that xylem flow increased in the early stages of fruit development and decreased in the late stage. Variations in xylem flow were related to the decrease in the hydraulic conductivity of xylem vessels but not to a decrease in the water potential gradient. The hydraulic conductivity of the fruit pedicel decreased during late growth due to embolism caused by a decrease in the fruit water potential. Further studies should establish the impact of the decrease in the hydraulic conductivity of the fruit pedicel on mango growth.
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Aliseda, Alberto, and Theodore J. Heindel. "X-Ray Flow Visualization in Multiphase Flows." Annual Review of Fluid Mechanics 53, no. 1 (2021): 543–67. http://dx.doi.org/10.1146/annurev-fluid-010719-060201.
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The use of X-ray flow visualization has brought a powerful new tool to the study of multiphase flows. Penetrating radiation can probe the spatial concentration of the different phases without the refraction, diffraction, or multiple scattering that usually produce image artifacts or reduce the signal-to-noise ratio below reliable values in optical visualization of multiphase flows; hence, X-ray visualization enables research into the three-dimensional (3D) structure of multiphase flows characterized by complex interfaces. With the commoditization of X-ray laboratory sources and wider access to synchrotron beam time for fluid mechanics, this novel imaging technique has shed light onto many multiphase flows of industrial and environmental interest under realistic 3D configurations and at realistic operating conditions (high Reynolds numbers and high volume fractions) that had defied study for decades. We present a broad survey of the most commonly studied multiphase flows (e.g., sprays, fluidized beds, bubble columns) in order to highlight the progress X-ray imaging has made in understanding the internal structure and multiphase coupling of these flows, and we discuss the potential of advanced tomography and time-resolved and particle tracking radiography for further study of multiphase flows.
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Iga, Keita. "Shear instability as a resonance between neutral waves hidden in a shear flow." Journal of Fluid Mechanics 715 (January 9, 2013): 452–76. http://dx.doi.org/10.1017/jfm.2012.529.
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AbstractA concept which explains unstable modes by resonance between two neutral waves is applied to instability in shear flows with non-uniform potential vorticity distribution. In basic flows where shear instability occurs, a pair of neutral waves which should resonate to form an unstable mode does not exist mathematically unless the basic potential vorticity is uniform, owing to the shear of the basic flow. However, if a small window region is made where the potential vorticity of the basic flow is uniform, regular neutral modes can exist. The neutral wave located at the centre of this window region, which corresponds to a mode where the jump in its first derivative at one end of the window region cancels that at the other end, can be considered to be the hidden neutral wave. It is equivalent to a continuous mode which does not have a jump in its first derivative at the critical point even though it can have a singularity of $(y\ensuremath{-} {y}_{c} )\log \vert y\ensuremath{-} {y}_{c} \vert $, in the limit of an infinitely small window region. Thus, a method for retrieving neutral waves hidden in the shear of the basic flow is proposed here. By sweeping the basic flow range with this uniform potential vorticity window, all the features of the hidden neutral wave appear. By applying this method, shear instability in a flow with a tanh-shaped basic velocity profile is well explained via the resonance between neutral waves.
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Bleker de Oliveira, Mariana, Paola Marino Dantonio, Veruska Lia Fook Alves, et al. "Multiple Myeloma Cancer Stem Cells: Immunophenotypic and Functional Characterization, Gene Expression Profiling and Therapeutic Targets." Blood 128, no. 22 (2016): 4434. http://dx.doi.org/10.1182/blood.v128.22.4434.4434.
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Abstract Background: Despite the increase in patients' survival over the last years, multiple myeloma (MM) remains incurable, being persistence of cancer stem cells (CSCs) a probable cause of drug resistance and disease relapse. It is possible to isolate these cells using surface antigen expression pattern (CD19+/CD34+/CD138-) and the activity of an enzyme from aldehyde dehydrogenase (ALDH) family (Boucher et al., 2012). We believe that using CD19 as potential marker of MM-CSCs makes CAR-T cell therapy against CD19 an option to eradicate residual MM disease. Aims: To isolate and characterize immunophenotypically, functionally and by gene expression the MM-CSCs derived from bone marrow (BM) samples of newly-diagnosed MM patients, focusing on identification of possible therapeutic targets. Methods: BM aspirates were collected and CD138+ cells were separated by magnetic sorting. The remaining cells were submitted to sorting by flow cytometry on FACSAria II (Becton, Dickinson and Company, Franklin Lakes, NJ, USA), labeled with anti-CD19 Pacific Blue (Invitrogen, Carlsbad, CA, USA), anti-CD34 PE Cy7 and anti-CD138 APC (both from Becton, Dickinson and Company, Franklin Lakes, NJ, USA) antibodies, in addition to Aldefluor™ reagent (StemCell Technology, Vancouver, British Columbia, Canada). RNA was extracted and pre-amplified for PCR array analysis using the RT² Profiler™ PCR Array Human Cancer Stem Cells(Qiagen, Hilden, Germany) to assess the expression profile of 84 genes related to cancer stem cells, and the results were evaluated with the online software provided by the platform manufacturer. Results: MM-CSCs (CD34+/CD19+/CD138-/ALDH1+) were isolated by flow cytometry from MM samples and presented median of 1,748.5 events (ranging from 56 to 16,633, n = 16). For comparison purposes, CD138+ MM tumor cells were isolated and used as "control group" (median of events 72,904, ranging from 1,536 to 312,504, n = 15). RNA from 16 MM-CSC samples and 6 controls were analyzed by qPCR. Considering 2-ΔCt calculation (GAPDH as normalizer) and fold change of 2, 11 genes were considered differentially expressed in MM-CSCs when compared to tumor plasma cells (p<0.05) (4 overexpressed and 7 underexpressed), as calculated by Student's T-test. Overexpression of CD38 in the control group confirms the origin of tumor plasma cells. Other genes overexpressed in tumor plasma cells include ITGA6 and PECAM1 (adhesion-related molecules); MERTK (signal transduction); BMI1; DKK1 (Wnt signaling pathway), and ID1 (cell migration and metastasis). Among the MM-CSCs overexpressed genes, ALDH1A1, ENG and ITGB1 are CSC markers and are related to stem cell functions; and WEE1 is a cell cycle-related gene which regulates G2-M checkpoint and promotes cell cycles arrest for further DNA repair. Discussion and Conclusions: Our preliminary data shows that cells isolated using Boucher et al. (2012) selected markers have MM-CSCs characteristics, validated by the expression of at least three genes related to CSCs: ALDH1A1, ENG and ITGB1. We also identified WEE1overexpression in MM-CSCs and this data is a new finding in MM studies. WEE1 overexpression has been described in several cancers, such as mantle cell lymphoma, colorectal cancer, breast cancer and glioblastoma. WEE1 inhibition by siRNAs or small molecule inhibitors AZD1775 (MK1775) and PD0407824, as shown in preclinical and clinical trials, impairs G2-M arrest and promotes premature entry in mitosis, leading to consequent cell death if DNA damage is irreparable (Mueller & Haas-Kogan, 2015). Therefore, these inhibitors could also be explored in MM treatment. Furthermore, we suggest that CAR-T cell therapy against CD19 might be and option to eradicate residual MM disease, since we confirmed that this antigen is present in MM-CSCs surface. Financial support: FAPESP 2010/17668-6 and FAPESP 2015/23983-5. Ethical approval: 0127/2014. Disclaimer: Oliveira MB and Dantonio PM equally contributed to this abstract. Disclosures No relevant conflicts of interest to declare.
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VERHOFF, A. "Two-dimensional potential flow solutions with separation." Journal of Fluid Mechanics 657 (July 21, 2010): 238–64. http://dx.doi.org/10.1017/s0022112010001448.
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A procedure for constructing two-dimensional incompressible potential flowfield solutions with separation and a recirculation region is presented. It naturally makes use of complex variable theory and other analysis techniques such as conformal mapping and the generalized Poisson integral formula. Flowfield determination is reduced to solution of a boundary value problem in various simple domains. The entire velocity field is described analytically; stream function and velocity potential contour maps are readily constructed. Example solutions are presented. Solutions for sharp leading edge airfoils at arbitrary angle of attack are completely determined, including the limiting angle of attack for upper-surface flow re-attachment. For other configurations (e.g. circular cylinder, backward-facing step) the analytical solution contains one or more free parameters, whose values may be inferred from boundary layer theory or experiment.
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Keil, Julian, Jana Timm, Iria SanMiguel, Hannah Schulz, Jonas Obleser, and Marc Schönwiesner. "Cortical brain states and corticospinal synchronization influence TMS-evoked motor potentials." Journal of Neurophysiology 111, no. 3 (2014): 513–19. http://dx.doi.org/10.1152/jn.00387.2013.
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Transcranial magnetic stimulation (TMS) influences cortical processes. Recent findings indicate, however, that, in turn, the efficacy of TMS depends on the state of ongoing cortical oscillations. Whereas power and phase of electromyographic (EMG) activity recorded from the hand muscles as well as neural synchrony between cortex and hand muscles are known to influence the effect of TMS, to date, no study has shown an influence of the phase of cortical oscillations during wakefulness. We applied single-pulse TMS over the motor cortex and recorded motor-evoked potentials along with the electroencephalogram (EEG) and EMG. We correlated phase and power of ongoing EEG and EMG signals with the motor-evoked potential (MEP) amplitude. We also investigated the functional connectivity between cortical and hand muscle activity (corticomuscular coherence) with the MEP amplitude. EEG and EMG power and phase in a frequency band around 18 Hz correlated with the MEP amplitude. High beta-band (∼34 Hz) corticomuscular coherence exhibited a positive linear relationship with the MEP amplitude, indicating that strong synchrony between cortex and hand muscles at the moment when TMS is applied entails large MEPs. Improving upon previous studies, we demonstrate a clear dependence of TMS-induced motor effects on the state of ongoing EEG phase and power fluctuations. We conclude that not only the sampling of incoming information but also the susceptibility of cortical communication flow depends cyclically on neural phase.
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Noblesse, Francis, Lijue Wang, and Chi Yang. "A Simple Verification Test for Nonlinear Flow Calculations Around a Ship Hull Steadily Advancing in Calm Water." Journal of Ship Research 56, no. 03 (2012): 162–69. http://dx.doi.org/10.5957/jsr.2012.56.3.162.
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Simple analytical relations that can readily be applied to verify a critical aspect of numerical predictions of fully nonlinear free-surface flows around ship hulls steadily advancing in calm water are given. The relations do not involve the flow field equations; that is, they are only based on the boundary conditions at the ship hull surface and at the free surface. These boundary conditions have a predominant influence on free-surface flows around advancing ship hulls. The analytical relations are exact for inviscid flows, and can be applied to numerical methods that solve either the Laplace equation (potential-flow methods) or the Euler flow equations (CFD Euler-flow methods). They provide a simple test to verify if numerical predictions given by nonlinear potential-flow or Euler-flow methods correctly satisfy the hull-surface and free-surface boundary conditions along the contact curve between the hull surface and the free surface. The relations might also be used to verify CFD methods that solve the RANS equations if they are applied at the edge of the viscous boundary layer. The analytical test can identify an inconsistency, which might point to a "method issue" related to a feature of a numerical method (e.g., a numerical-differentiation scheme) or an "implementation issue" in the implementation of the method (e.g., a poor discretization). For purposes of illustration, the test is applied to predictions of flows around the Wigley parabolic hull given by two CFD methods that solve the Euler equations with fully nonlinear boundary conditions at the free surface. This illustrative example demonstrates that the test can indeed be useful to identify numerical inaccuracies. The analytical relations can also be used to determine experimental values of the flow velocity at a ship wave profile that correspond to measurements of the wave profile.
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Sturzenegger, Matthieu, Kris Holm, Carie-Ann Lau, and Matthias Jakob. "Debris-Flow and Debris-Flood Susceptibility Mapping for Geohazard Risk Prioritization." Environmental and Engineering Geoscience 27, no. 2 (2021): 179–94. http://dx.doi.org/10.2113/eeg-d-20-00006.
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ABSTRACT Regional-scale assessments for debris-flow and debris-flood propagation and avulsion on fans can be challenging. Geomorphological mapping based on aerial or satellite imagery requires substantial field verification effort. Surface evidence of past events may be obfuscated by development or obscured by repeat erosion or debris inundation, and trenching may be required to record the sedimentary architecture and date past events. This paper evaluates a methodology for debris-flow and debris-flood susceptibility mapping at regional scale based on a combination of digital elevation model (DEM) metrics to identify potential debris source zones and flow propagation modeling using the Flow-R code that is calibrated through comparison to mapped alluvial fans. The DEM metrics enable semi-automated identification and preliminary, process-based classification of streams prone to debris flow and debris flood. Flow-R is a susceptibility mapping tool that models potential flow inundation based on a combination of spreading and runout algorithms considering DEM topography and empirical propagation parameters. The methodology is first evaluated at locations where debris-flow and debris-flood hazards have been previously assessed based on field mapping and detailed numerical modeling. It is then applied over a 125,000 km2 area in southern British Columbia, Canada. The motivation for the application of this methodology is that it represents an objective and repeatable approach to susceptibility mapping, which can be integrated in a debris-flow and debris-flood risk prioritization framework at regional scale to support risk management decisions.
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Murakami, Shinsuke. "Flow Scenarios and Resource Potentials for End-of-life Electric Appliances." Material Cycles and Waste Management Research 20, no. 5 (2009): 237–44. http://dx.doi.org/10.3985/mcwmr.20.237.
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Findlay, L. M. "Reading and Teaching Troilus Otherwise: St Maure, Chaucer, Henryson." Florilegium 16, no. 1 (1999): 61–75. http://dx.doi.org/10.3138/flor.16.007.
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Medieval studies has it all . At the end of the twentieth century, whatever one wishes to explore, one can find it adumbrated or more plainly available in the middle ages. Nor does one have to listen (as I have done with pleasure and profit over the years) to that committed teacher and scholar, Douglas Wurtele, in order to appreciate this. I was assured of that by Matthew P. MacDiarmid when I was an undergraduate at Aberdeen. When I went to Oxford as a graduate student, the endless potential and compelling actualities of medieval studies were even more palpable than at Aber-deen, especially for someone intending to work in the nineteenth century . However, the Aberdeen all proved to be different from the Oxford all, most notably in the place granted to the so-called Scottish Chaucerians in a decidedly Anglocentric scheme of things. And this conflicted sense of all — what it is and who gets to define it—helped open the door for me on what has in the last two decades been a site for some of the most important and intermittently-productive debates in literary studies and in the humanities more generally.
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Condie, Scott A., and Ross W. Griffiths. "Convection in a rotating cavity: modelling ocean circulation." Journal of Fluid Mechanics 207 (October 1989): 453–74. http://dx.doi.org/10.1017/s002211208900265x.
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Large-scale oceanic flows, ranging from large estuaries to basin-scale abyssal circulation, can be driven by imposed lateral density gradients and are significantly influenced by the Earth's rotation. Some essential features of such flows have been incorporated into a laboratory model by differentially heating and cooling the vertical endwalls of a shallow rectangular cavity, rotating about a vertical axis through its centre. In this paper, the flow observed after this system had been allowed to develop to a steady mean state is described. Measurements were made of the velocity and temperature fields, as well as the variability in temperature field associated with eddy motions. The temperature data were also used to calculate the potential vorticity distribution within the cavity. These results indicate that the heated and cooled end-walls acted not only as continuous sources of buoyancy, but also of anomalous potential vorticity. It is shown that the potential vorticity served as an indicator and tracer of the laboratory flow. The structure and location of boundary currents were largely determined by nonlinear potential vorticity dynamics which resulted in a mean circulation consisting of two basin-scale counter-rotating gyres. This flow differed markedly from the initial boundary currents set up by Kelvin waves.
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Ingram, Grant, David Gregory-Smith, and Neil Harvey. "Investigation of a Novel Secondary Flow Feature in a Turbine Cascade With End Wall Profiling." Journal of Turbomachinery 127, no. 1 (2005): 209–14. http://dx.doi.org/10.1115/1.1812321.
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A novel secondary flow feature, previously unreported for turbine blading as far as the authors are aware, has been discovered. It has been found that it is possible to separate part of the inlet boundary layer on the blade row end wall as it is being over-turned and rolled up into the passage vortex. This flow feature has been discovered during a continuing investigation into the aerodynamic effects of non-axisymmetric end wall profiling. Previous work, using the low speed linear cascade at Durham University, has shown the potential of end wall profiling for reducing secondary losses. The latest study, the results of which are described here, was undertaken to determine the limits of what end wall profiling can achieve. The flow has been investigated in detail with pressure probe traversing and surface flow visualization. This has found that the inlet boundary locally separates, on the early suction side of the passage, generating significant extra loss which feeds directly into the core of the passage vortex. The presence of this new feature gives rise to the unexpected result that the secondary flow, as determined by the exit flow angle deviations and levels of secondary kinetic energy, can be reduced while at the same time the loss is increased. CFD was found to calculate the secondary flows moderately well compared with measurements. However, CFD did not predict this new feature, nor the increase in loss it caused. It is concluded that the application of non-axisymmetric end wall profiling, although it has been shown to be highly beneficial, can give rise to adverse features that current CFD tools are unable to predict. Improvements to CFD capability are required in order to be able to avoid such features, and obtain the full potential of end wall profiling.
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Ayyalil, Fathima Mohiyaddin, Samantha J. Montague, Sarah Hicks, et al. "Platelet Function in Paroxysmal Nocturnal Haemoglobinuria." Blood 134, Supplement_1 (2019): 4884. http://dx.doi.org/10.1182/blood-2019-130291.
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Introduction Paroxysmal nocturnal haemoglobinuria (PNH) is a rare acquired clonal haematopoietic stem cell disorder characterised by haemolytic anaemia, thrombosis and bone marrow failure. Thrombosis is considered a major cause for high morbidity and mortality in PNH patients (Hillmen P et al N Eng J Med 1995). However, the underlying mechanisms of thrombosis in PNH are still poorly understood. Various factors including defective interactions between the complement system, platelets and coagulation systems have been proposed (Peacock-Young B et al Haematologica 2017). Platelet function and clot formation in this disorder have not been comprehensively evaluated. Here we describe standard and novel techniques to evaluate platelet function in blood from PNH patients, to elucidate the underlying pro-thrombotic mechanisms. Methods Whole blood was collected from five PNH patients and compared to same-day healthy donor (HD) controls. The samples were collected at trough for those patients who were on eculizumab (Complement C5 inhibitor used in the treatment of PNH). Surface levels of platelet adhesion proteins and activation markers P-selectin and phosphatidylserine (PS) were assessed using flow cytometry. Plasma soluble GPVI (a platelet-specific activation marker) and cytokine levels were measured by ELISA. Clot formation was assessed by viscoelastic testing (ROTEM). Adhesion of platelets to collagen under flow in a whole blood assay was evaluated by Digital Holographic Microscopy (DHM) and thrombus height, surface area and volume quantified using custom-built MatLab-based software. Results Clinical characteristics of PNH patients were highly variable: two patients had history of thrombosis, three patients were on eculizumab, four patients were thrombocytopenic (<150x109/L) and three were haemolysing. Platelet surface levels of adhesion/signalling receptor proteins including glycoproteins (GP) Iba, GPVI, aIIbb3, and ADAM10 (membrane expressed enzyme responsible for shedding GPVI from the surface) were all at lower ends of HD ranges. P-selectin and PS levels under resting and activated conditions and plasma soluble GPVI levels were comparable to same day HD. There were no differences between HD and PNH groups for levels of interleukin (IL) -6, IL-1β, tumour necrosis factor α, IL-17A, interferon γ or monocyte chemoattractant protein-1 (MCP-1). ROTEM analysis revealed slower formation of smaller clots in PNH patients, which correlated with their platelet count. Peak thrombus height and volume analysed by DHM were not different from data obtained with HD blood at both venous and arterial shear rates. However, both parameters were increased in PNH samples at arterial shearrate, when adjusted for platelet count (p<0.01). Conclusion Analysis of these PNH patients with highly variable clinical characteristics did not identify a unifying platelet lesion. DHM could detect and quantify parameters of small thrombi in real time, in PNH patient samples and these data were consistent with enhanced thrombogenic potential in PNH patients. Mechanisms beyond platelet activation that contribute to increased thrombosis in these patients and the impact of eculizumab therapy on thrombotic propensity need to be explored further. Disclosures D'Rozario: Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees.
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Wightman, Emma L. "Potential benefits of phytochemicals against Alzheimer's disease." Proceedings of the Nutrition Society 76, no. 2 (2017): 106–12. http://dx.doi.org/10.1017/s0029665116002962.
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Our current therapeutic drugs for Alzheimer's disease are predominantly derived from the alkaloid class of plant phytochemicals. These drugs, such as galantamine and rivastigmine, attenuate the decline in the cholinergic system but, as the alkaloids occupy the most dangerous end of the phytochemical spectrum (indeed they function as feeding deterrents and poisons to other organisms within the plant itself), they are often associated with unpleasant side effects. In addition, these cholinesterase inhibiting alkaloids target only one system in a disorder, which is typified by multifactorial deficits. The present paper will look at the more benign terpene (such asGinkgo biloba, Ginseng,Melissa officinalis(lemon balm) andSalvia lavandulaefolia(sage)) and phenolic (such as resveratrol) phytochemicals; arguing that they offer a safer alternative and that, as well as demonstrating efficacy in cholinesterase inhibition, these phytochemicals are able to target other salient systems such as cerebral blood flow, free radical scavenging, anti-inflammation, inhibition of amyloid-β neurotoxicity, glucoregulation and interaction with other neurotransmitters (such as γ-aminobutyric acid) and signalling pathways (e.g. via kinase enzymes).
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Grobbe, N., and S. Barde-Cabusson. "Self-Potential Studies in Volcanic Environments: A Cheap and Efficient Method for Multiscale Fluid-Flow Investigations." International Journal of Geophysics 2019 (October 20, 2019): 1–19. http://dx.doi.org/10.1155/2019/2985824.
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We demonstrate the value of using the self-potential method to study volcanic environments, and particularly fluid flow in those environments. We showcase the fact that self-potential measurements are a highly efficient way to map large areas of volcanic systems under challenging terrain conditions, where other geophysical techniques may be challenging or expensive to deploy. Using case studies of a variety of volcano types, including tuff cones, shield volcanoes, stratovolcanoes, and monogenetic fields, we emphasize the fact that self-potential signals enable us to study fluid flow in volcanic settings on multiple spatial and temporal scales. We categorize the examples into the following three multiscale fluid-flow processes: (1) deep hydrothermal systems, (2) shallow hydrothermal systems, and (3) groundwater. These examples highlight the different hydrological, hydrothermal, and structural inferences that can be made from self-potential signals, such as insight into shallow and deep hydrothermal systems, cooling behavior of lava flows, different hydrogeological domains, upwelling, infiltration, and lateral groundwater and hydrothermal fluid flow paths and velocities, elevation of the groundwater level, crater limits, regional faults, rift zones, incipient collapse limits, structural domains, and buried calderas. The case studies presented in this paper clearly demonstrate that the measured SP signals are a result of the coplay between microscale processes (e.g., electrokinetic, thermoelectric) and macroscale structural and environmental features. We discuss potential challenges and their causes when trying to uniquely interpret self-potential signals. Through integration with different geophysical and geochemical data types such as subsurface electrical resistivity distributions obtained from, e.g., electrical resistivity tomography or magnetotellurics, soil CO2 flux, and soil temperature, it is demonstrated that the hydrogeological interpretations obtained from SP measurements can be better constrained and/or validated.
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Sun, T., J. Xu, and Z. F. Yang. "Environmental flow assessments in estuaries based on an integrated multi-objective method." Hydrology and Earth System Sciences 17, no. 2 (2013): 751–60. http://dx.doi.org/10.5194/hess-17-751-2013.
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Abstract. An integrated multi-objective method for environmental flow assessments was developed that considered variability of potential habitats as a critical factor in determining how ecosystems respond to hydrological alterations. Responses of habitat area, and the magnitude of those responses as influenced by salinity and water depth, were established and assessed according to fluctuations in river discharge and tidal currents. The requirements of typical migratory species during pivotal life-stage seasons (e.g., reproduction and juvenile growth) and natural flow variations were integrated into the flow-needs assessment. Critical environmental flows for a typical species were defined based on two primary objectives: (1) high level of habitat area and (2) low variability of habitat area. After integrating the water requirements for various species with the maximum acceptable discharge boundary, appropriate temporal limits of environmental flows for ecosystems were recommended. The method was applied in the Yellow River estuary in eastern Shandong province, China. Our results show that, while recommended environmental flows established with variability of potential habitats in mind may not necessarily benefit short-term survival of a typical resident organism on a limited temporal or spatial scale, they may encourage long-term, stable biodiversity and ecosystem health. Thus, short-term ecosystem losses may be compensated by significant long-term gains.
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Trevisani, Sebastiano, and Marco Cavalli. "Topography-based flow-directional roughness: potential and challenges." Earth Surface Dynamics 4, no. 2 (2016): 343–58. http://dx.doi.org/10.5194/esurf-4-343-2016.
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Abstract. Surface texture analysis applied to high-resolution digital terrain models (HRDTMs) is a promising approach for extracting useful fine-scale morphological information. Surface roughness, considered here as a synonym of surface texture, can have a discriminant role in the detection of different geomorphic processes and factors. Very often, the local morphology presents, at different scales, anisotropic characteristics that could be taken into account when calculating or measuring surface roughness. The high morphological detail of HRDTMs permits the description of different aspects of surface roughness, beyond an evaluation limited to isotropic measures of surface roughness. The generalization of the concept of roughness implies the need to refer to a family of specific roughness indices capable of capturing specific multiscale and anisotropic aspects of surface morphology. An interesting set of roughness indices is represented by directional measures of roughness that can be meaningful in the context of analyzed and modeled flow processes. Accordingly, we test the application of a flow-oriented directional measure of roughness based on the geostatistical bivariate index MAD (median of absolute directional differences), which is computed considering surface gravity-driven flow direction. MAD is derived from a modification of a variogram and is specifically designed for the geomorphometric analysis of HRDTMs. The presented approach shows the potential impact of considering directionality in the calculation of roughness indices. The results demonstrate that the use of flow-directional roughness can improve geomorphometric modeling (e.g., sediment connectivity and surface texture modeling) and the interpretation of landscape morphology.
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LIN, PENGZHI, YINNA WU, JUNLI BAI, and QUANHONG LIN. "A NUMERICAL STUDY OF DAM-BREAK FLOW AND SEDIMENT TRANSPORT FROM A QUAKE LAKE." Journal of Earthquake and Tsunami 05, no. 05 (2011): 401–28. http://dx.doi.org/10.1142/s1793431111001169.
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Dam-break flows are simulated numerically by a two-dimensional shallow-water-equation model that combines a hydrodynamic module and a sediment transport module. The model is verified by available analytical solutions and experimental data. It is demonstrated that the model is a reliable tool for the simulation of various transient shallow water flows and the associated sediment transport and bed morphology on complex topography. The validated model is then applied to investigate the potential dam-break flows from Tangjiashan Quake Lake resulting from Wenchuan Earthquake in 2008. The dam-break flow evolution is simulated by using the model in order to provide the flooding patterns (e.g., arrival time and flood height) downstream. Furthermore, the sediment transport and bed morphology simulation is performed locally to study the bed variation under the high-speed dam-break flow.
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Trevisani, S., and M. Cavalli. "Topography-based flow-directional roughness: potential and challenges." Earth Surface Dynamics Discussions 3, no. 4 (2015): 1399–444. http://dx.doi.org/10.5194/esurfd-3-1399-2015.
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Abstract. Surface texture analysis applied to High Resolution Digital Terrain Models (HRDTMs) is a promising approach for extracting useful fine-scale morphological information. Surface roughness, considered here as a synonym of surface texture, can have a discriminant role in the detection of different geomorphic processes and factors. Very often, the local morphology presents, at different scales, anisotropic characteristics that could be taken into account when calculating or measuring surface roughness. The high morphological detail of HRDTMs permits the description of different aspects of surface roughness, beyond an evaluation limited to isotropic measures of surface roughness. The generalization of the concept of roughness implies the need to refer to a family of specific roughness indices capable of capturing specific multi-scale and anisotropic aspects of surface morphology. An interesting set of roughness indices is represented by directional measures of roughness that can be meaningful in the context of analyzed and modeled flow processes. Accordingly, we test the application of a flow-oriented directional measure of roughness based on the geostatistical bivariate index MAD (median of absolute directional differences), which is computed considering surface gravity-driven flow direction. MAD is derived from a modification of a variogram and is specifically designed for the geomorphometric analysis of HRDTMs. The presented approach shows the potential impact of considering directionality in the calculation of roughness indices. The results demonstrate that the use of flow directional roughness can improve geomorphometric modeling (e.g., sediment connectivity and surface texture modeling) and the interpretation of landscape morphology.
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Boss, E., N. Paldor, and L. Thompson. "Stability of a potential vorticity front: from quasi-geostrophy to shallow water." Journal of Fluid Mechanics 315 (May 25, 1996): 65–84. http://dx.doi.org/10.1017/s0022112096002339.
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The linear stability of a simple two-layer shear flow with an upper-layer potential vorticity front overlying a quiescent lower layer is investigated as a function of Rossby number and layer depths. This flow configuration is a generalization of previously studied flows whose results we reinterpret by considering the possible resonant interaction between waves. We find that instabilities previously referred to as ‘ageostrophic’ are a direct extension of quasi-geostrophic instabilities.Two types of instability are discussed: the classic long-wave quasi-geostrophic baroclinic instability arising from an interaction of two vortical waves, and an ageostrophic short-wave baroclinic instability arising from the interaction of a gravity wave and a vortical wave (vortical waves are defined as those that exist due to the presence of a gradient in potential vorticity, e.g. Rossby waves). Both instabilities are observed in oceanic fronts. The long-wave instability has length scale and growth rate similar to those found in the quasi-geostrophic limit, even when the Rossby number of the flow is O(1).We also demonstrate that in layered shallow-water models, as in continuously stratified quasi-geostrophic models, when a layer intersects the top or bottom boundaries, that layer can sustain vortical waves even though there is no apparent potential vorticity gradient. The potential vorticity gradient needed is provided at the top (or bottom) intersection point, which we interpret as a point that connects a finite layer with a layer of infinitesimal thickness, analogous to a temperature gradient on the boundary in a continuously stratified quasi-geostrophic model.
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Labelle, Alexandre, and Jean-Marc Frayret. "Agent-Based Model for End-of-Life Product Flow Analysis." Resources 7, no. 3 (2018): 42. http://dx.doi.org/10.3390/resources7030042.
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This paper presents an agent-based simulation model for end-of-life product flow analysis in recuperation and recycling supply networks that focuses on individual consumer behaviors. The simulation model is applied to a deposit-return program on wine bottles that could be developed in the province of Quebec. Canadian data was used to calibrate and validate the model. A series of experiments was then conducted with three artificial populations to analyse how they would react to several implementation scenarios of this end-of-life product flow strategy. The results suggest that the distance to the nearest depot is an important decision factor, but less predominant than the ownership of a private vehicle and the deposit value. The results also indicate that the use of agent-based modeling combined with the theory of planned behavior (TPB) can produce modular behavior models, that are intuitive and simple, to better understand consumer-behavior-driven supply chains. Such models can be used to give insights to decision-makers and policy-makers about the potential performance of end-of-life product flows strategies and further facilitate efficient resource management.
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Koylu, Caglar, and Diansheng Guo. "Design and evaluation of line symbolizations for origin–destination flow maps." Information Visualization 16, no. 4 (2016): 309–31. http://dx.doi.org/10.1177/1473871616681375.
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We present the results of a user study comparing variants of commonly used line symbolizations for directed origin–destination flow maps. Our design and evaluation consisted of five line symbolizations that employ a combination of following visual variables: arrowheads, origin–destination coloring (color hue, and value), line shortening, line width, tapered edges (varying width from wide to narrow, and narrow to wide), and curvature asymmetry and strength. To guide our evaluation, we used a task-by-type typology and chose four representative tasks that are commonly used in flow map reading: identifying dominant direction of flows, flows with the highest magnitude (volume), spatial focusing of long flows toward a destination, and clusters of high net-exports (net-outflow). We systematically analyzed user responses and task performance which we measured by task completion time and accuracy. We designed a web-based flow mapping and testing framework and recruited the participants from Amazon Mechanical Turk. To demonstrate the application and user experiment, we used 16 commodity flow data sets in the United States from 2007 and systematically rotated the layouts to evaluate the effect of layout orientation. From this study, we can conclude that there is potential usefulness for all of the five symbolizations we tested; however, the influence of the design on performance and perception depends on the type of the task. Also, we found that data and layout orientation have significant effects on performance and perception of patterns in flow maps which we attribute to the change in visual saliency of node and flow patterns in relation to the way users scan the map. We recommend that the choice of line symbolization should be guided by a task taxonomy which end users are expected to perform. We discuss various design trade-offs and recommendations and potential future work for designing and evaluating line symbolizations for flow mapping.
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Glöser-Chahoud, Simon, and Frank Schultmann. "Potential Contribution of Secondary Materials to Overall Supply - The Example of the European Cobalt Cycle." Materials Science Forum 959 (June 2019): 11–21. http://dx.doi.org/10.4028/www.scientific.net/msf.959.11.
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Higher efficiency in raw material recycling is discussed as a key strategy to decrease the environmental impact of resource consumption and to improve materials’ availability in order to mitigate supply risks. However, particularly in the case of technology metals, demand is driven by specific emerging technologies from which recycling will not be possible before the end of their useful lifetimes. Hence, the availability of secondary materials is limited by the amount of obsolete products as well as their collection, separation and treatment during waste management and recycling. In this paper, we present the results of a dynamic material flow model for cobalt as a key raw material for lithium-ion batteries at an European level (EU28). This model aims at quantifying the current state of recycling and future recycling potentials from end-of-life (EoL) product flows. While it is expectable that obsolete large battery packs from (hybrid) electric vehicles will be efficiently collected in future, EoL Li-ion battery flows will remain dominated by smaller electronic equipment (smartphones, laptops etc.) in the coming years and the model results show a significant potential for improvements in collection and material recovery from EoL batteries in Europe. A major challenge will be the collection of smaller batteries and Waste Electrical and Electronic Equipment (WEEE) in general from which a significant share of total European cobalt demand could be recovered in the coming years.
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FRANCO, ELISA, DAVID N. PEKAREK, JIFENG PENG, and JOHN O. DABIRI. "Geometry of unsteady fluid transport during fluid–structure interactions." Journal of Fluid Mechanics 589 (October 8, 2007): 125–45. http://dx.doi.org/10.1017/s0022112007007872.
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We describe the application of tools from dynamical systems to define and quantify the unsteady fluid transport that occurs during fluid–structure interactions and in unsteady recirculating flows. The properties of Lagrangian coherent structures (LCS) are used to enable analysis of flows with arbitrary time-dependence, thereby extending previous analytical results for steady and time-periodic flows. The LCS kinematics are used to formulate a unique, physically motivated definition for fluid exchange surfaces and transport lobes in the flow. The methods are applied to numerical simulations of two-dimensional flow past a circular cylinder at a Reynolds number of 200; and to measurements of a freely swimming organism, the Aurelia aurita jellyfish. The former flow provides a canonical system in which to compare the present geometrical analysis with classical, Eulerian (e.g. vortex shedding) perspectives of fluid–structure interactions. The latter flow is used to deduce the physical coupling that exists between mass and momentum transport during self-propulsion. In both cases, the present methods reveal a well-defined, unsteady recirculation zone that is not apparent in the corresponding velocity or vorticity fields. Transport rates between the ambient flow and the recirculation zone are computed for both flows. Comparison of fluid transport geometry for the cylinder crossflow and the self-propelled swimmer within the context of existing theory for two-dimensional lobe dynamics enables qualitative localization of flow three-dimensionality based on the planar measurements. Benefits and limitations of the implemented methods are discussed, and some potential applications for flow control, unsteady propulsion, and biological fluid dynamics are proposed.
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Hsia, Carleton JC, and Li Ma. "SOD3-Mimetic As a Complement for Genetic Therapy in Sickle Cell Disease." Blood 132, Supplement 1 (2018): 2355. http://dx.doi.org/10.1182/blood-2018-99-120287.
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Abstract Background and Objectives: Genetic therapy relieves transfusion-dependence in patients 12 years and older with ß-Thalassemia (1) There is an urgent need to develop a complementary approach to genetic therapy for children younger than 12 years of age. The objective of this report is to describe the potential development of an extracellular superoxide dismutase-mimetic (SOD3-mimetic) to relieve sickle cell disease (SCD) children susceptible to stroke from being transfusion-dependent in order to avoid stroke. SanFlow [aka polynitroxylated pegylated hemoglobin (PNPH)], a SOD3-mimetic has been evaluated and approved by the FDA for further development as drug for the treatment of traumatic brain injury (TBI) complicated by hemorrhagic shock (HS), stroke, and SCD. PK&PD studies demonstrated that SanFlow works as a macromolecular SOD3-mimetic by protecting the endogenous vascular nitric oxide (NO) leading to enhanced blood flow. SanFlow has been shown to protect against superoxide induced hypoxia and inflammation in transgenic SCD and rat model of ischemic stroke as well as a mouse model of TBI+HS. In a rat middle cerebral artery occlusion (MCAO) model of stroke the spreading of the hypoxic core of the ischemic brain as measured by Pial arterial diameter is maintained over 2 hours post onset of stroke with associated reduction in inflammatory markers and brain infraction (3). In a mouse TBI+SH model, SanFlow was shown to be superior to fresh shed whole blood. The safety and efficacy of SanFlow was tested over a 50 fold dose range (i.e. from 0.1 to 5 times the shed blood volume). SanFlow was shown to work at extremely low volume in conjunction with volume replacement crystalloid to substitute whole blood resuscitation (3). Experimental Results: Using Berkeley model of sickle mice (Hba0/0 Hbb0/0Tg (HuminiLCRα1GγAγδβS) we have measures the PK&PD of SanFlow as a complementary or a substitute for genetic therapy. We have non-invasively measured the blood flow and vasoconstriction using transgenic SS mice (N=7) against WT littermates (N=4) as control. A single bolus dose of SanFlow (20ml/kg at hemoglobin of 4g/dl) significantly corrected the aortic stiffness and pulmonary flow of the SS mice to that of WT littermates (P<0.05). This is also correlated with the decrease of superoxide level in the lung as measure by Luminol activity assays (which fluoresces in the presence of superoxide) (P<0.05). Plasma cGMP (downstream effector of NO and natriuretic peptide activity) and NOx (breakdown product of NO and a measure of NOS activity) concentrations were measured in plasma of mice after infusion of SanFlow. SanFlow infusion was shown to significantly increased plasma cGMP concentrations in plasma. SanFlow infusion also resulted in a significant increase in NOx in plasma after infusion (P<0.05). SanFlow resulted in an increase in plasma cGMP and NOx in SS mice. Thus, the pathophysiological defects or difference of SS mice and WT littermates are corrected by SanFlow infusion. Conclusions:The present results support development of SanFlow, delivered through continuous infusion, for anemic SCD children to prevent the development of blood transfusion dependency in order to avoid stroke and painful vaso-occlusive crisis (VOC). These results also demonstrated that SanFlow can be used safely and effectively in the elimination of serious painful vaso-occlusive crisis and protect silent and major strokes. Clinical trials of SanFlow in SCD children, prior to their transfusion dependence, as well as in transfusion-dependent teenagers and adults with SCD patients are warranted. By extension, ß-Thalassemia patients can also be treated like SCD patients using SanFlow to relieve them from dependence on life-long blood exchange transfusion. However, these patients would be treated with SOD3-mimetic while waiting for genetic therapy. References: Thompson AA., et.al. Eng. J. Med 2018; 398: 1479-1493 Brockman EC., et. al. 2017 Neurotrauma, 34(7):1337-50 Cao S., et. al. 2017 J. Am Heart Assoc., 6(9):e006505. Disclosures Hsia: AntiRadical Therapeutics LLC: Employment.
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Chang, Chih-Hua. "Numerical Analyses of Wave Generation and Vortex Formation under the Action of Viscous Fluid Flows over a Depression." Journal of Marine Science and Engineering 7, no. 5 (2019): 141. http://dx.doi.org/10.3390/jmse7050141.
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Transient free-surface deformations and evolving vortices due to the passage of flows over a submerged cavity are simulated. A two-dimensional stream function–vorticity formulation with a free-surface model is employed. Model results are validated against the limiting case of pure lid-driven cavity flow with comparisons of the vortical flow pattern and velocity profiles. The verification of the free-surface computations are also carried out by comparing results with published potential flow solutions for cases of flows over a depressed bottom topography. The agreements are generally good. Investigations are extended to other viscous flow conditions, where the cavity is set to have the normalized dimension of one by one when scaled by the still water depth. The free-surface elevations and streamline patterns for cases with Froude numbers ranging from 0.5 to 1.1 and different Reynolds numbers (Re = 5000 and 500) are calculated. At the condition of near-critical flow (Fr ≈ 1.0), the phenomenon of upstream advancing solitons is produced. Viscous effects on the free-surface profile reveal that at a lower value of Re (e.g., Re = 500) larger advancing solitary waves are generated. Vortical flow patterns in the cavity are examined for the cases with Fr = 1.0 and various values of Re. When Re = 5000, the vortex pattern includes a primary and a weak, but dominated secondary vortices at the time reaching a nearly quasi-steady motion. For the case of lower Re (e.g., Re = 500), a steady-state vortex pattern can be established with a clockwise primary vortex mostly occupied inside the cavity.
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Frank, F., B. W. McArdell, C. Huggel, and A. Vieli. "The importance of entrainment and bulking on debris flow runout modeling: examples from the Swiss Alps." Natural Hazards and Earth System Sciences 15, no. 11 (2015): 2569–83. http://dx.doi.org/10.5194/nhess-15-2569-2015.
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Abstract. This study describes an investigation of channel-bed entrainment of sediment by debris flows. An entrainment model, developed using field data from debris flows at the Illgraben catchment, Switzerland, was incorporated into the existing RAMMS debris-flow model, which solves the 2-D shallow-water equations for granular flows. In the entrainment model, an empirical relationship between maximum shear stress and measured erosion is used to determine the maximum potential erosion depth. Additionally, the average rate of erosion, measured at the same field site, is used to constrain the erosion rate. The model predicts plausible erosion values in comparison with field data from highly erosive debris flow events at the Spreitgraben torrent channel, Switzerland in 2010, without any adjustment to the coefficients in the entrainment model. We find that by including bulking due to entrainment (e.g., by channel erosion) in runout models a more realistic flow pattern is produced than in simulations where entrainment is not included. In detail, simulations without entrainment show more lateral outflow from the channel where it has not been observed in the field. Therefore the entrainment model may be especially useful for practical applications such as hazard analysis and mapping, as well as scientific case studies of erosive debris flows.
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Walton, Gabriel, Georgia Fotopoulos, and Robert Radovanovic. "Extraction and Comparison of Spatial Statistics For Geometric Parameters of Sedimentary Layers from Static and Mobile Terrestrial Laser Scanning Data." Environmental and Engineering Geoscience 25, no. 2 (2019): 155–68. http://dx.doi.org/10.2113/eeg-2068.
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ABSTRACT Terrestrial laser scanning (TLS) is a surveying technology that has seen increasing use in the field of geosciences in recent years. One potential application for this technology is to aid in quantitative stratigraphy. Given a point cloud containing multiple lithologies, the points associated with a specific lithology can be analyzed to quantify the geometric characteristics of that lithology, such as apparent dip, thickness, and spacing. In this study, a semi-automated work flow to perform such a characterization is presented and applied to a case study from an oil sands pit mine in the Athabasca region of Alberta, Canada. The results obtained using data collected with mobile and static TLS systems are compared to evaluate the effects of the various measurements and resolutions on the resulting stratigraphic statistics. In addition, mobile data collected for a small portion of the pit that was actively being mined are compared over time to evaluate changes in sedimentary layering in the direction perpendicular to the pit face. This component of the study highlights the impact of data quality on the resulting interpretations and represents a potential methodology for enhancing three-dimensional quantitative spatial modeling in a sedimentary environment.