Journal articles: 'Circulation switching'

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Uhlíř, V., M. Urbánek, L. Hladík, J. Spousta, M.-Y. Im, P. Fischer, N. Eibagi, J. J. Kan, E. E. Fullerton, and T. Šikola. "Dynamic switching of the spin circulation in tapered magnetic nanodisks." Nature Nanotechnology 8, no. 5 (April 21, 2013): 341–46. http://dx.doi.org/10.1038/nnano.2013.66.

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Wen, Y., Z. Feng, B. F. Miao, R. X. Cao, L. Sun, B. You, D. Wu, et al. "Fast and controllable switching the circulation and polarity of magnetic vortices." Journal of Magnetism and Magnetic Materials 370 (December 2014): 68–75. http://dx.doi.org/10.1016/j.jmmm.2014.06.049.

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Grady, William R., Mark D. Hayward, John O. G. Billy, and Francesca A. Florey. "Contraceptive switching among currently married women in the United States." Journal of Biosocial Science 21, S11 (1989): 117–32. http://dx.doi.org/10.1017/s002193200002544x.

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SummaryThis study examines contraceptive method switching among married women in the US. It enquires first into the effect of method type and women's socioeconomic characteristics on the risk of switching to each of six methods, including no method, and secondly into the previous methods used by women who adopt specific contraceptive means. The results indicate a great deal of circulation among all method types and of movement to unprotected intercourse. The adoption of sterilization is greatest among women not previously using any contraceptive method.

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Adeeb, Nimer, Christopher S. Ogilvy, Christoph J. Griessenauer, and Ajith J. Thomas. "Expanding the Indications for Flow Diversion: Treatment of Posterior Circulation Aneurysms." Neurosurgery 86, Supplement_1 (December 16, 2019): S76—S84. http://dx.doi.org/10.1093/neuros/nyz344.

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Abstract Posterior circulation aneurysms are often associated with a higher risk of rupture and compressive symptoms compared to their anterior circulation counterpart. Due to high morbidity and mortality associated with microsurgical treatment of those aneurysms, endovascular therapy gained ascendance as the preferred method of treatment. Flow diversion has emerged as a promising treatment option for posterior circulation aneurysms with a higher occlusion rate compared to other endovascular techniques and a lower complication rate compared to microsurgery. While treatment of saccular and dissecting aneurysms is often associated with comparatively good outcomes, fusiform and dolichoectatic aneurysms should be carefully selected prior to treatment to avoid devastating thromboembolic complications. Occlusion of covered posterior circulation branches showed no correlation with ischemic complications, and appropriate antiplatelet regimen and switching Clopidogrel nonresponders to different antiplatelet agents were associated with lower complication rates following flow diversion of posterior circulation aneurysms.

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Loginov, V. S., and V. G. Milyutin. "TEMPERATURE FIELDS IN THE WELL AT THE SWITCHED-OFF CIRCULATION OF DRILLING FLUID." Oil and Gas Studies, no. 5 (November 1, 2017): 75–80. http://dx.doi.org/10.31660/0445-0108-2017-5-75-80.

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The thermal model of the well after switching off the flow of drilling mud is considered. The received results are auxiliary for formulation of the general model. The general model in conjunction with temperature data of drilling mud on a surface will allow to reveal layers of the hydrocarbons, penetrated earlier with drilling.

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Wang, Yonggang, Tianyou Chai, Jun Fu, Jing Sun, and Hong Wang. "Adaptive Decoupling Switching Control of the Forced-Circulation Evaporation System Using Neural Networks." IEEE Transactions on Control Systems Technology 21, no. 3 (May 2013): 964–74. http://dx.doi.org/10.1109/tcst.2012.2193883.

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Hossain, M. S., R. Islam, and K. A. Khan. "DC Conduction and Switching Mechanisms in Electroformed Al/ZnTe:V/Cu Devices at Atmospheric Pressure." ISRN Materials Science 2011 (July 7, 2011): 1–6. http://dx.doi.org/10.5402/2011/823237.

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Vanadium-doped zinc telluride (ZnTe:V) thin film sandwiched by two different metal electrodes, that is, Al/ZnTe:V/Cu structure, was deposited onto the glass substrate by e-beam deposition technique in vacuum at a pressure of ~8 × 10−4 Pa. The deposition rate of the film was maintained at 2.052 nms−1. Circulation current was measured through this device as a function of potential difference applied across the structure. The Al/ZnTe:V/Cu structures exhibit memory switching characteristics at atmospheric pressure in room temperature. Switching characteristics of deposited Al/ZnTe:V/Cu structure as a memory device have been investigated in detail for various vanadium compositions, thicknesses of ZnTe:V films as well as various film temperatures, respectively. In all cases, it is seen that the metal/insulator/metal (Al/ZnTe:V/Cu) structures based on ZnTe:V can undergo an electroforming process and exhibit voltage-controlled negative resistance (VCNR) or a new switching process. It is also observed that the electric field, temperature, thickness, and dopant composition have important role in the switching characteristics. Switching characteristics have been interpreted by using a filamentary model. The switching effects of Al/ZnTe:V/Cu device may have important applications in the energy-oriented devices.

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Kim, Jun-Mo, Jeong Lee, Kyung Ryu, and Chung-Yuen Won. "Power Device Temperature-Balancing Control Method for a Phase-Shift Full-Bridge Converter." Energies 13, no. 7 (April 2, 2020): 1623. http://dx.doi.org/10.3390/en13071623.

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In this paper, a switching method is proposed for power device temperature-balancing in a phase-shift full-bridge (PSFB) converter. PSFB is commonly used for applications that require high efficiency, because a zero-voltage switching (ZVS) operation is possible on the primary-side. In PSFB, the circulation current complicates ZVS under a light-load condition, which generates heat. Meanwhile, the heat generated in PSFB creates a temperature deviation between the lagging leg and the leading leg, which shortens the lifetime of the power device, thereby reducing system reliability and efficiency. To solve this problem, previous studies applied a pulse-width modulation (PWM) switching method for light and medium loads, and a phase-shift switching method for the region where ZVS is possible. Although this method has the advantage of easy control, the maximum temperature of the legs of the PSFB increases with medium loads. In this paper, a temperature-balancing algorithm—a temperature-balance control—is proposed to decrease the leg temperature using switching based on position exchanges of the leading leg and lagging leg along with PWM switching. Temperature-balance control minimizes leg temperature deviation under light load conditions. The proposed control method provides a minimum temperature difference between the two legs and high efficiency.

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Young, Sally. "The Decline of Traditional News and Current Affairs Audiences in Australia." Media International Australia 131, no. 1 (May 2009): 147–59. http://dx.doi.org/10.1177/1329878x0913100116.

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With attention focused on the battle for news ratings between Channels Seven and Nine, an underlying trend has tended to go unnoticed: audiences have been switching off televised news and current affairs programs since the 1990s. Drawing on detailed OzTAM ratings, this article shows how this is particularly true for specific audience segments. Allied with this is the longer-term decline in newspaper circulation. These data raise a central question: are Australians merely switching off ‘outdated’ media such as TV and newspapers (and getting their news from somewhere else such as the internet), or are they switching off the genre of news/current affairs altogether? This article weighs the evidence and concludes that the news audience is fragmenting in particular ways, especially by age, and that some (but certainly not all) groups are going online for news.

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Masada, Kenta, Kazuo Shimamura, Toru Kuratani, and Yoshiki Sawa. "Management of foetal circulation by switching to pulsatile perfusion during cardiovascular surgery in pregnancy." European Journal of Cardio-Thoracic Surgery 53, no. 3 (September 2, 2017): 680–81. http://dx.doi.org/10.1093/ejcts/ezx319.

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Kang, Dong-Hun, Yong-Won Kim, Yang-Ha Hwang, Jaechan Park, Jeong-Hyun Hwang, and Yong-Sun Kim. "Switching Strategy for Mechanical Thrombectomy of Acute Large Vessel Occlusion in the Anterior Circulation." Stroke 44, no. 12 (December 2013): 3577–79. http://dx.doi.org/10.1161/strokeaha.113.002673.

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Siecker, Juan, Kanzumba Kusakana, and Bubele Papy Numbi. "Optimal Switching Control of Flow in PV/T Systems with Forced Circulation: Model Development." Advanced Science Letters 24, no. 11 (November 1, 2018): 8081–84. http://dx.doi.org/10.1166/asl.2018.12496.

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Faranda, Davide, Giacomo Masato, Nicholas Moloney, Yuzuru Sato, Francois Daviaud, Bérengère Dubrulle, and Pascal Yiou. "The switching between zonal and blocked mid-latitude atmospheric circulation: a dynamical system perspective." Climate Dynamics 47, no. 5-6 (December 10, 2015): 1587–99. http://dx.doi.org/10.1007/s00382-015-2921-6.

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Jia, Gui Xi, and Jia Tai Song. "Design and Simulation of Numeral Soft-Switching ZVZCS-PWM Arc-Welding Power." Applied Mechanics and Materials 380-384 (August 2013): 3139–44. http://dx.doi.org/10.4028/www.scientific.net/amm.380-384.3139.

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Zvzcs-pwm inverter combines the advantages of ZVS-PWM inverter and ZCS-PWM inverter, it can solve the problems of switching loses and extra circulation. Furthermore, it is provided with less duty cycle loss, small parasitic oscillation of the secondary side and large load rage conducted by soft-switching. A conjoint system based on MCU and DSP can make full use of the advanced ability of the event management, data processing and computing speed, which improves accuracy and real-time digital control of arc welding power. This paper introduces design of main circuit and control circuit of arc welding power and the working process of the zvzcs-pwm inverter. The simulation with matlab demonstrates the feasibility of the design.

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Sadowski, Ireneusz, and Nataliia Pohorila. "Game of Seats: Electoral Rules, Revolutions, and Affiliation Switching in Ukraine, 1990–2014." East European Politics and Societies: and Cultures 32, no. 1 (November 13, 2017): 142–67. http://dx.doi.org/10.1177/0888325417728771.

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Since gaining its independence in 1990, Ukraine has experienced two revolutions and a war in the east of the country. Meanwhile, it has sampled all three major electoral systems (majoritarian, proportional, and mixed) and has created dozens of major parties and political blocs. Such a volatile context has consequences for such crucial political issues as accountability and circulation of the political class. At the same time, it allows researchers to address questions concerning the sources of change and stability in the politics of countries in transition. In particular, the case of Ukraine allows us to pinpoint the effects of popular upheavals and changing institutional arrangements on the stability of a political scene and the population of politicians. Data limitations of previous studies have prevented such a necessarily detailed temporal accounting. We analyze it for all Ukrainian MP hopefuls during the 1990–2014 period using the East European Parliamentarian and Candidate data (EAST PaC). The issue of political stability was approached by examining affiliation switching and dropping out in all consecutive elections to the Verkhovna Rada. The results reveal that revolutionary events had relatively minor immediate effects on the circulation of the political class, while individual strategies were highly dependent on the electoral rules working in conjunction with other traits of the political system.

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Knippenberg, Stephanie, Joost Smolders, Mariëlle Thewissen, Evelyn Peelen, Jan Willem Cohen Tervaert, Raymond Hupperts, and Jan Damoiseaux. "Effect of vitamin D3 supplementation on peripheral B cell differentiation and isotype switching in patients with multiple sclerosis." Multiple Sclerosis Journal 17, no. 12 (June 20, 2011): 1418–23. http://dx.doi.org/10.1177/1352458511412655.

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Background: Vitamin D has been proposed as a promoter of immune homeostasis in multiple sclerosis (MS). During the past decade, the focus of the effects of vitamin D has been on dendritic cells and on T cells. Since there is an increasing interest in the role of B cells in the pathophysiology of MS, we studied the role of vitamin D on B cells in vivo in patients with MS. Objective: We explored the effects of 12 weeks high-dose vitamin D3 supplementation on peripheral B cell differentiation, immunoglobulin production and levels of B cell activating factor (BAFF) in 15 patients with MS. Methods: Circulating B cell subsets were characterized by flow cytometry. Plasma immunoglobulin levels were assessed by nephelometry. Plasma BAFF levels were assessed by enzyme-linked immunosorbent assay (ELISA). Results: Although a significant increase serum 25-hydroxyvitamin D was induced, we found no significant shift in B cell differentiation, isotype switching, or plasma BAFF levels. Conclusion: In patients with MS, supplementation of high doses vitamin D3 does not have substantial effects on phenotypic markers of B cell differentiation in circulating B cells. Future studies may unravel more subtle changes in the B cell compartment, either in the circulation or in the central nervous system.

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Rapaport, Alain, Terence Bayen, Matthieu Sebbah, Andres Donoso-Bravo, and Alfredo Torrico. "Dynamical modeling and optimal control of landfills." Mathematical Models and Methods in Applied Sciences 26, no. 05 (February 25, 2016): 901–29. http://dx.doi.org/10.1142/s0218202516500214.

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We propose a simple model of landfill and study a minimal time control problem where the re-circulation leachate is the manipulated variable. We propose a scheme to construct the optimal strategy by dividing the state space into three subsets [Formula: see text], [Formula: see text] and the complementary. On [Formula: see text] and [Formula: see text], the optimal control is constant until reaching target, while it can exhibit a singular arc outside these two subsets. Moreover, the singular arc could have a barrier. In this case, we prove the existence of a switching curve that passes through a point of prior saturation under the assumption that the set [Formula: see text] intersects the singular arc. Numerical computations allow then to determine the switching curve and depict the optimal synthesis.

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Kingsley, Paul D., Jeffrey Malik, Rachel L. Emerson, Timothy P. Bushnell, Kathleen E. McGrath, Laura A. Bloedorn, Michael Bulger, and James Palis. "“Maturational” globin switching in primary primitive erythroid cells." Blood 107, no. 4 (February 15, 2006): 1665–72. http://dx.doi.org/10.1182/blood-2005-08-3097.

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Mammals have 2 distinct erythroid lineages. The primitive erythroid lineage originates in the yolk sac and generates a cohort of large erythroblasts that terminally differentiate in the bloodstream. The definitive erythroid lineage generates smaller enucleated erythrocytes that become the predominant cell in fetal and postnatal circulation. These lineages also have distinct globin expression patterns. Our studies in primary murine primitive erythroid cells indicate that βH1 is the predominant β-globin transcript in the early yolk sac. Thus, unlike the human, murine β-globin genes are not up-regulated in the order of their chromosomal arrangement. As primitive erythroblasts mature from proerythroblasts to reticulocytes, they undergo a βH1- to ϵy-globin switch, up-regulate adult β1- and β2-globins, and down-regulate ζ-globin. These changes in transcript levels correlate with changes in RNA polymerase II density at their promoters and transcribed regions. Furthermore, the ϵy- and βH1-globin genes in primitive erythroblasts reside within a single large hyperacetylated domain. These data suggest that this “maturational” βH1- to ϵy-globin switch is dynamically regulated at the transcriptional level. Globin switching during ontogeny is due not only to the sequential appearance of primitive and definitive lineages but also to changes in globin expression as primitive erythroblasts mature in the bloodstream.

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Song, Hao, Eric Brown, Russell Hawkins, and Penger Tong. "Dynamics of large-scale circulation of turbulent thermal convection in a horizontal cylinder." Journal of Fluid Mechanics 740 (February 6, 2014): 136–67. http://dx.doi.org/10.1017/jfm.2013.655.

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AbstractA systematic study of the effects of cell geometry on the dynamics of large-scale flows in turbulent thermal convection is carried out in horizontal cylindrical cells of different lengths filled with water. Four different flow modes are identified with increasing aspect ratio $\Gamma $. For small aspect ratios ($\Gamma \leq 0.16$), the flow is highly confined in a thin disc-like cell with a quasi-two-dimensional (quasi-2D) large-scale circulation (LSC) in the circular plane of the cell. For larger aspect ratios ($\Gamma >0.16$), we observe periodic switching of the angular orientation $\theta $ of the rotation plane of LSC between the two longest diagonals of the cell. The sides of the container along which the LSC oscillates changes at a critical aspect ratio $\Gamma _{c}\simeq 0.82$. The measured switching period is equal to the LSC turnover time for $\Gamma \leq \Gamma _c$, shows a sharp increase at $\Gamma _{c}$ and decays exponentially to the LSC turnover time with increasing $\Gamma $. For $\Gamma \geq 1.3$, a periodic rocking of LSC along the long axis of the cylinder is also observed. The measured probability density function $P(\theta )$ of the LSC orientation $\theta $ peaks at the two diagonal positions, and its shape is described by a phenomenological model proposed by Brown & Ahlers (Phys. Fluids, vol. 20, 2008b, 075101; J. Fluid Mech., vol. 638, 2009, pp. 383–400). Using this model, we describe the dynamics of the LSC orientation $\theta $ by stochastic motion in a double-well potential. The potential is predicted from a model in which the sidewall shape produces an orientation-dependent pressure on the LSC. This model also captures key features of the four flow modes. The experiment reveals an interesting array of rich dynamics of LSC in the horizontal cylinders, which are very different from those observed in the upright cylindrical convection cells. The success of the model for both upright and horizontal cylinders suggests that it can be applied to different geometries.

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Ertz, Myriam, Jonathan Deschênes, and Emine Sarigöllü. "From User to Provider: Switching Over in the Collaborative Economy." Sustainability 13, no. 10 (May 18, 2021): 5662. http://dx.doi.org/10.3390/su13105662.

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The collaborative economy comprises resource circulation systems where consumers can act as both obtainers and providers of products and services. Despite considerable research on collaborative economies, there is a dearth of understanding of how individuals switch from being an obtainer to a provider. We address this void in the literature. The objective of this paper is to conceptually introduce and empirically substantiate the switchover concept, which occurs when an individual switches from a user role to a provider one—drawing on 31 in-depth semi-structured interviews with collaborative economy obtainers. The findings suggest that personal values, learning experience, social benefits, mutuality, and peer influence drive obtainers to become providers. In contrast, distrusting strangers, a sense of intimacy, a lack of resources to share, and a lack of skills inhibit the switchover process. Our findings contextualize the drivers and inhibitors idiosyncratically to convert obtainers into providers, offer important implications for managers, contribute to the collaborative economy and sharing economy literature and suggest compelling avenues for future research.

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Pampana, Enrico, Sebastiano Fabiano, Gianluca De Rubeis, Luca Bertaccini, Alessandro Stasolla, Alberto Pingi, Valeria Cozzolino, et al. "Switch Strategy from Direct Aspiration First Pass Technique to Solumbra Improves Technical Outcome in Endovascularly Treated Stroke." International Journal of Environmental Research and Public Health 18, no. 5 (March 6, 2021): 2670. http://dx.doi.org/10.3390/ijerph18052670.

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Background: The major endovascular mechanic thrombectomy (MT) techniques are: Stent-Retriever (SR), aspiration first pass technique (ADAPT) and Solumbra (Aspiration + SR), which are interchangeable (defined as switching strategy (SS)). The purpose of this study is to report the added value of switching from ADAPT to Solumbra in unsuccessful revascularization stroke patients. Methods: This is a retrospective, single center, pragmatic, cohort study. From December 2017 to November 2019, 935 consecutive patients were admitted to the Stroke Unit and 176/935 (18.8%) were eligible for MT. In 135/176 (76.7%) patients, ADAPT was used as the first-line strategy. SS was defined as the difference between first technique adopted and the final technique. Revascularization was evaluated with modified Thrombolysis In Cerebral Infarction (TICI) with success defined as mTICI ≥ 2b. Procedural time (PT) and time to reperfusion (TTR) were recorded. Results: Stroke involved: Anterior circulation in 121/135 (89.6%) patients and posterior circulation in 14/135 (10.4%) patients. ADAPT was the most common first-line technique vs. both SR and Solumbra (135/176 (76.7%) vs. 10/176 (5.7%) vs. 31/176 (17.6%), respectively). In 28/135 (20.7%) patients, the mTICI was ≤ 2a requiring switch to Solumbra. The vessel’s diameter positively predicted SS result (odd ratio (OR) 1.12, confidence of interval (CI) 95% 1.03–1.22; p = 0.006). The mean number of passes before SS was 2.0 ± 1.2. ADAPT to Solumbra improved successful revascularization by 13.3% (107/135 (79.3%) vs. 125/135 (92.6%)). PT was superior for SS comparing with ADAPT (71.1 min (CI 95% 53.2–109.0) vs. 40.0 min (CI 95% 35.0–45.2); p = 0.0004), although, TTR was similar (324.1 min (CI 95% 311.4–387.0) vs. 311.4 min (CI 95% 285.5–338.7); p = 0.23). Conclusion: Successful revascularization was improved by 13.3% after switching form ADAPT to Solumbra (final mTICI ≥ 2b was 92.6%). Vessel’s diameter positively predicted recourse to SS.

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Li, Ruiyun, Ottar N. Bjørnstad, and Nils Chr Stenseth. "Switching vaccination among target groups to achieve improved long-lasting benefits." Royal Society Open Science 8, no. 6 (June 2021): 210292. http://dx.doi.org/10.1098/rsos.210292.

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The development of vaccines has opened a way to lower the public health and societal burden of COVID-19 pandemic. To achieve sustainable gains in the long term, switching the vaccination from one target group to a more diverse portfolio should be planned appropriately. We lay out a general mathematical framework for comparing alternative vaccination roll-out strategies for the year to come: single focus groups: (i-a) the high-risk older age groups and (i-b) the core-sociable groups; and two focus groups: (ii-a) mixed vaccination of both the high-risk and core-sociable groups simultaneously and (ii-b) cyclic vaccination switching between groups. Featuring analyses of all relevant data including age pyramids for 15 representative countries with diverse social mixing patterns shows that mixed strategies that result in both direct and indirect protection of high-risk groups may be better for the overall societal health impact of COVID-19 vaccine roll-out. Of note, over time switching the priority from high-risk older age groups to core-sociable groups responsible for heightened circulation and thus indirect risk may be increasingly advantageous.

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Sempf, Mario, Klaus Dethloff, Dörthe Handorf, and Michael V. Kurgansky. "Circulation Regimes due to Attractor Merging in Atmospheric Models." Journal of the Atmospheric Sciences 64, no. 6 (June 2007): 2029–44. http://dx.doi.org/10.1175/jas3923.1.

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From a dynamical systems theory perspective, the mechanisms of atmospheric regime behavior in a barotropic model, a pseudobarotropic model, and a baroclinic three-level model, where all of them show quite realistic regimes, are unveiled. Along with this, the role played by multiple equilibria for the emergence of regimes in barotropic models is critically reexamined. In the barotropic model, a sequence of bifurcations is observed, which leads to the merging of coexisting attractors and results in two pronounced regimes corresponding to high- and low-index flow. The pseudobarotropic model is constructed from the three-level model by introducing a strong internal friction between the levels and switching off the interfacial diabatic forcing, and it has essentially the same bifurcation properties and regimes as the truly barotropic model. A continuous metamorphosis between the pseudobarotropic and the original baroclinic three-level model is accomplished by a linear interpolation of parameters and forcing fields between these two models. Both local and global bifurcations occurring during this transition to baroclinicity are analyzed in detail, yielding two main results. First, almost all of the multiple steady states of the pseudobarotropic model owe their existence merely to the fact that the surface friction has generally to be chosen unphysically weak in barotropic models in order to obtain chaotic behavior. Second, the circulation regimes in both the pseudobarotropic model and the baroclinic three-level model are proven to emerge from the unification of multiple attractors, which coexist at intermediate strength of baroclinicity and correspond to low- or high-index flow configurations, respectively.

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Helvind, Morten H., James F. McCarthy, Michiaki Imamura, Lourdes Prieto, George E. Sarris, Jonathan J. Drummond-Webb, and Roger B. B. Mee. "Ventriculo-arterial discordance: switching the morphologically left ventricle into the systemic circulation after 3 months of age1." European Journal of Cardio-Thoracic Surgery 14, no. 2 (August 1998): 173–78. http://dx.doi.org/10.1016/s1010-7940(98)00172-9.

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Li, Q., A. Tan, A. Scholl, A. T. Young, M. Yang, C. Hwang, A. T. N'Diaye, E. Arenholz, J. Li, and Z. Q. Qiu. "Electrical switching of the magnetic vortex circulation in artificial multiferroic structure of Co/Cu/PMN-PT(011)." Applied Physics Letters 110, no. 26 (June 26, 2017): 262405. http://dx.doi.org/10.1063/1.4990987.

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Bessac, Julie, Pierre Ailliot, Julien Cattiaux, and Valerie Monbet. "Comparison of hidden and observed regime-switching autoregressive models for (u, v)-components of wind fields in the northeastern Atlantic." Advances in Statistical Climatology, Meteorology and Oceanography 2, no. 1 (February 29, 2016): 1–16. http://dx.doi.org/10.5194/ascmo-2-1-2016.

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Abstract. Several multi-site stochastic generators of zonal and meridional components of wind are proposed in this paper. A regime-switching framework is introduced to account for the alternation of intensity and variability that is observed in wind conditions due to the existence of different weather types. This modeling blocks time series into periods in which the series is described by a single model. The regime-switching is modeled by a discrete variable that can be introduced as a latent (or hidden) variable or as an observed variable. In the latter case a clustering algorithm is used before fitting the model to extract the regime. Conditional on the regimes, the observed wind conditions are assumed to evolve as a linear Gaussian vector autoregressive (VAR) model. Various questions are explored, such as the modeling of the regime in a multi-site context, the extraction of relevant clusterings from extra variables or from the local wind data, and the link between weather types extracted from wind data and large-scale weather regimes derived from a descriptor of the atmospheric circulation. We also discuss the relative advantages of hidden and observed regime-switching models. For artificial stochastic generation of wind sequences, we show that the proposed models reproduce the average space–time motions of wind conditions, and we highlight the advantage of regime-switching models in reproducing the alternation of intensity and variability in wind conditions.

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Palis, James, Jeff Malik, Rachael L. Emerson, Tim P. Bushnell, Kathleen E. McGrath, Michael Bulger, and Paul D. Kingsley. "“Maturational” Globin Switching in Primary Primitive Erythroid Cells." Blood 106, no. 11 (November 16, 2005): 3634. http://dx.doi.org/10.1182/blood.v106.11.3634.3634.

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Abstract Mammals have two distinct erythroid lineages. The “definitive” erythroid lineage generates small, enucleated erythrocytes that constitute the predominant cell type in the fetal and postnatal circulation. It is preceded by the “primitive” erythroid lineage, which originates in the yolk sac and generates a semi-synchronous wave of large erythroblasts that terminally differentiate in the bloodstream. This feature provides a unique opportunity to investigate changes in gene expression during erythroid maturation. Here, we have examined expression of the various α- and β-globin genes in purified populations of primary primitive erythroid cells isolated from progressive developmental time-points of mouse embryogenesis. Our studies, using both in situ hybridization and quantitative PCR, indicate that βH1 is the predominant β-globin transcript in the early yolk sac. Thus, unlike the human, the murine β-globin genes are not up-regulated in the order of their chromosomal arrangement. As primitive erythroblasts mature from proerythroblasts to reticulocytes, they undergo a βH1- to εy-globin switch, up-regulate low levels of the adult β1- and β2-globins, and down-regulate ζ-globin. These changes in transcript levels correlate with changes in RNA polymerase II density at their promoters and transcribed regions as assayed by ChIP assays. Furthermore, we found that the εy- and βH1-globin genes in primitive erythroblasts reside within a single large hyperacetylated domain. Taken together, these results are consistent with the notion that this βH1- to εy-globin “maturational” switch is dynamically regulated at the transcriptional level. We conclude that the embryonic to adult globin switch that occurs during murine ontogeny is due not only to the sequential appearance of primitive and definitive erythroid lineages but also to striking changes in globin gene expression that occur as primitive erythroblasts mature in the bloodstream.

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Higgins, Paul A. T., Michael D. Mastrandrea, and Stephen H. Schneider. "Dynamics of climate and ecosystem coupling: abrupt changes and multiple equilibria." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 357, no. 1421 (May 29, 2002): 647–55. http://dx.doi.org/10.1098/rstb.2001.1043.

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Interactions between subunits of the global climate–biosphere system (e.g. atmosphere, ocean, biosphere and cryosphere) often lead to behaviour that is not evident when each subunit is viewed in isolation. This newly evident behaviour is an emergent property of the coupled subsystems. Interactions between thermohaline circulation and climate illustrate one emergent property of coupling ocean and atmospheric circulation. The multiple thermohaline circulation equilibria that result caused abrupt climate changes in the past and may cause abrupt climate changes in the future. Similarly, coupling between the climate system and ecosystem structure and function produces complex behaviour in certain regions. For example, atmosphere–biosphere interactions in the Sahel region of West Africa lead to multiple stable equilibria. Either wet or dry climate equilibria can occur under otherwise identical forcing conditions. The equilibrium reached is dependent on past history (i.e. initial conditions), and relatively small perturbations to either climate or vegetation can cause switching between the two equilibria. Both thermohaline circulation and the climate–vegetation system in the Sahel are prone to abrupt changes that may be irreversible. This complicates the relatively linear view of global changes held in many scientific and policy communities. Emergent properties of coupled socio–natural systems add yet another layer of complexity to the policy debate. As a result, the social and economic consequences of possible global changes are likely to be underestimated in most conventional analyses because these nonlinear, abrupt and irreversible responses are insufficiently considered.

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Siecker, J., K. Kusakana, and B. P. Numbi. "Optimal switching control of PV/T systems with energy storage using forced water circulation: Case of South Africa." Journal of Energy Storage 20 (December 2018): 264–78. http://dx.doi.org/10.1016/j.est.2018.09.019.

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Chebanyuk, S. V., O. E. Svyrydyuk, O. F. Sydorenko, and M. Yu Mamonova. "Cerebral arteriovenous malformations: features of the functioning of the blood circulation system after endovascular treatment with long-term monitoring." Endovascular Neuroradiology 33, no. 3 (December 31, 2020): 19–28. http://dx.doi.org/10.26683/2304-9359-2020-3(33)-19-28.

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Objective ‒ to determine the features of the functioning of the circulatory system in patients with arteriovenous malformations (AVM) of the brain after endovascular operations with long-term observation.Materials and methods. 479 patients with cerebral AVM were examined and treated, of which 377 (78.7 %) were men and 102 (21.3 %) were women. The average age of patients was (27.5±3.5) years. Patients aged 18‒30 years predominated (75.4 %). A dynamic observation of 347 patients after endovascular treatment after 3, 6, 12 and 24 months and more was carried out. Patients underwent cerebral angiography, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, echocardiography, Doppler cardiography, electrocardiography, duplex scanning of cerebral vessels.Results. The study shows the effect of arteriovenous shunting on cerebral and systemic hemodynamics in general. Switching off AVM from the cerebral blood flow improved cerebral hemodynamics already in the early postoperative period, the changes were more significant after 3‒6 months of observation and in some cases reached values in healthy individuals 2 years after the operation. In 52.8 % of patients with AVM, systemic circulation disorders occurred due to an increase in heart rate, minute and stroke blood volumes, left ventricular ejection fraction with an increase in mechanical load on the heart, which led to changes in systolic contraction and diastolic relaxation of the left ventricle of the heart with the development of heart failure. Switching off the AVM from the cerebral blood flow did not cause significant changes in heart functions in the early postoperative period; positive changes occurred over a long period. Dynamic observation showed a positive restructuring of the functioning of the circulatory system in patients after endovascular exclusion of the malformation.Conclusions. Arteriovenous malformations are hemodynamically active systems that lead to hemodynamic-perfusion changes, both at the local and at the general hemodynamic level. The exclusion of the malformation from the bloodstream contributes to the regression of disorders of cerebral and intracardiac blood flow caused by the anatomical and functional characteristics of the malformation itself and its clinical course.

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Skrypnyk, Denys, and Iryna Yurchak. "The Online Platform „eSchool“." Advances in Cyber-Physical Systems 6, no. 1 (January 23, 2021): 63–69. http://dx.doi.org/10.23939/acps2021.01.063.

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The internet is a global network that is used in any industry. Large corporations have long used the electronic way of doing business. Due to the COVID-19 pandemic, more and more government and commercial structures are switching to online and, therefore, using the electronic circulation of documents and other important things for them. Educational institutions were the most unprepared for such changes, and therefore, they faced an acute question of how to transfer everything online. The purpose of the development is to design and implement a convenient, simple, and most importantly, fast accounting system for educational institutions, which can reflect the educational process in a convenient way, both for students/students and teachers/teachers.

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Lilienthal, Friederike, and Christoph Jacobi. "Nonlinear forcing mechanisms of the migrating terdiurnal solar tide and their impact on the zonal mean circulation." Annales Geophysicae 37, no. 5 (October 10, 2019): 943–53. http://dx.doi.org/10.5194/angeo-37-943-2019.

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Abstract. We investigate the forcing mechanisms of the terdiurnal solar tide in the middle atmosphere using a mechanistic global circulation model. In order to quantify their individual contributions, we perform several model experiments and separate each forcing mechanism by switching off the remaining sources. We find that the primary excitation is owing to the terdiurnal component of solar radiation absorption in the troposphere and stratosphere. Secondary sources are nonlinear tide–tide interactions and gravity wave–tide interactions. Thus, although the solar heating clearly dominates the terdiurnal forcing in our simulations, we find that nonlinear tidal and gravity wave interactions contribute in certain seasons and at certain altitudes. By slightly enhancing the different excitation sources, we test the sensitivity of the background circulation to these changes of the dynamics. As a result, the increase of terdiurnal gravity wave drag can strongly affect the middle and upper atmosphere dynamics, including an irregular change of the terdiurnal amplitude, a weakening of neutral winds in the thermosphere, and a significant temperature change in the thermosphere, depending on the strength of the forcing. On the contrary, the influence of nonlinear tidal interactions on the middle atmosphere background dynamics is rather small.

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Giannakis, Dimitrios, Anastasiya Kolchinskaya, Dmitry Krasnov, and Jörg Schumacher. "Koopman analysis of the long-term evolution in a turbulent convection cell." Journal of Fluid Mechanics 847 (May 29, 2018): 735–67. http://dx.doi.org/10.1017/jfm.2018.297.

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We analyse the long-time evolution of the three-dimensional flow in a closed cubic turbulent Rayleigh–Bénard convection cell via a Koopman eigenfunction analysis. A data-driven basis derived from diffusion kernels known in machine learning is employed here to represent a regularized generator of the unitary Koopman group in the sense of a Galerkin approximation. The resulting Koopman eigenfunctions can be grouped into subsets in accordance with the discrete symmetries in a cubic box. In particular, a projection of the velocity field onto the first group of eigenfunctions reveals the four stable large-scale circulation (LSC) states in the convection cell. We recapture the preferential circulation rolls in diagonal corners and the short-term switching through roll states parallel to the side faces which have also been seen in other simulations and experiments. The diagonal macroscopic flow states can last as long as 1000 convective free-fall time units. In addition, we find that specific pairs of Koopman eigenfunctions in the secondary subset obey enhanced oscillatory fluctuations for particular stable diagonal states of the LSC. The corresponding velocity-field structures, such as corner vortices and swirls in the midplane, are also discussed via spatiotemporal reconstructions.

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Blinov, Andrei, and Anna Andrijanovits. "New DC/DC Converter for Electrolyser Interfacing with Stand-Alone Renewable Energy System." Electrical, Control and Communication Engineering 1, no. 1 (December 1, 2012): 24–29. http://dx.doi.org/10.2478/v10314-012-0004-1.

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Abstract This paper presents findings of a R&D project targeted to the development of a galvanically isolated step-down DC/DC converter for electrolyzer integration with renewable energy systems. The presented converter with an improved control algorithm for the full-bridge active rectifier features reduced energy circulation and switching losses. The performance can be improved under wide input voltage and load variations. The advantages of the converter were verified with a 1 kW converter prototype and the test results were in full agreement with the expected waveforms. The presented steadystate operation principle and mathematical analysis of the converter based on the simulation and experimental results can be used as design guidelines for component and parameter estimation in practical applications.

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Chorny, Alejo, Sandra Casas-Recasens, Jordi Sintes, Meimei Shan, Nadia Polentarutti, Ramón García-Escudero, A. Cooper Walland, et al. "The soluble pattern recognition receptor PTX3 links humoral innate and adaptive immune responses by helping marginal zone B cells." Journal of Experimental Medicine 213, no. 10 (September 12, 2016): 2167–85. http://dx.doi.org/10.1084/jem.20150282.

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Pentraxin 3 (PTX3) is a fluid-phase pattern recognition receptor of the humoral innate immune system with ancestral antibody-like properties but unknown antibody-inducing function. In this study, we found binding of PTX3 to splenic marginal zone (MZ) B cells, an innate-like subset of antibody-producing lymphocytes strategically positioned at the interface between the circulation and the adaptive immune system. PTX3 was released by a subset of neutrophils that surrounded the splenic MZ and expressed an immune activation–related gene signature distinct from that of circulating neutrophils. Binding of PTX3 promoted homeostatic production of IgM and class-switched IgG antibodies to microbial capsular polysaccharides, which decreased in PTX3-deficient mice and humans. In addition, PTX3 increased IgM and IgG production after infection with blood-borne encapsulated bacteria or immunization with bacterial carbohydrates. This immunogenic effect stemmed from the activation of MZ B cells through a neutrophil-regulated pathway that elicited class switching and plasmablast expansion via a combination of T cell–independent and T cell–dependent signals. Thus, PTX3 may bridge the humoral arms of the innate and adaptive immune systems by serving as an endogenous adjuvant for MZ B cells. This property could be harnessed to develop more effective vaccines against encapsulated pathogens.

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Zhang, Jianliang, Hanbo Hu, Nadia L. Palma, Jeffrey K. Harrison, Kamal K. Mubarak, Robin D. Carrie, Hassan Alnuaimat, Xiaoqiang Shen, Defang Luo, and Jawaharlal M. Patel. "Hypoxia-induced endothelial CX3CL1 triggers lung smooth muscle cell phenotypic switching and proliferative expansion." American Journal of Physiology-Lung Cellular and Molecular Physiology 303, no. 10 (November 15, 2012): L912—L922. http://dx.doi.org/10.1152/ajplung.00014.2012.

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Distal arterioles with limited smooth muscles help maintain the high blood flow and low pressure in the lung circulation. Chronic hypoxia induces lung distal vessel muscularization. However, the molecular events that trigger alveolar hypoxia-induced peripheral endothelium modulation of vessel wall smooth muscle cell (SMC) proliferation and filling of nonmuscular areas are unclear. Here, we investigated the role of CX3CL1/CX3CR1 system in endothelial-SMC cross talk in response to hypoxia. Human lung microvascular endothelial cells responded to alveolar oxygen deficiency by overproduction of the chemokine CX3CL1. The CX3CL1 receptor CX3CR1 is expressed by SMCs that are adjacent to the distal endothelium. Hypoxic release of endothelial CX3CL1 induced SMC phenotypic switching from the contractile to the proliferative state. Inhibition of CX3CR1 prevented CX3CL1 stimulation of SMC proliferation and monolayer expansion. Furthermore, CX3CR1 deficiency attenuated spiral muscle expansion, distal vessel muscularization, and pressure elevation in response to hypoxia. Our findings indicate that the capillary endothelium relies on the CX3CL1-CX3CR1 axis to sense alveolar hypoxia and promote peripheral vessel muscularization. These results have clinical significance in the development of novel therapeutics that target mechanisms of distal arterial remodeling associated with pulmonary hypertension induced by oxygen deficiency that is present in people living at high altitudes and patients with obstructive lung diseases.

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Franzke, Christian, Illia Horenko, Andrew J. Majda, and Rupert Klein. "Systematic Metastable Atmospheric Regime Identification in an AGCM." Journal of the Atmospheric Sciences 66, no. 7 (July 1, 2009): 1997–2012. http://dx.doi.org/10.1175/2009jas2939.1.

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Abstract In this study the authors apply a recently developed clustering method for the systematic identification of metastable atmospheric regimes in high-dimensional datasets generated by atmospheric models. The novelty of this approach is that it decomposes the phase space in, possibly, overlapping clusters and simultaneously estimates the most likely switching sequence among the clusters. The parameters of the clustering and switching are estimated by a finite element approach. The switching among the clusters can be described by a Markov transition matrix. Possible metastable regime behavior is assessed by inspecting the eigenspectrum of the associated transition probability matrix. The recently introduced metastable data-analysis method is applied to high-dimensional datasets produced by a barotropic model and a comprehensive atmospheric general circulation model (GCM). Significant and dynamically relevant metastable regimes are successfully identified in both models. The metastable regimes in the barotropic model correspond to blocked and zonal states. Similar regime states were already previously identified in highly reduced phase spaces of just one and two dimensions in the same model. Next, the clustering method is applied to a comprehensive atmospheric GCM in which seven significant flow regimes are identified. The spatial structures of the regimes correspond to, among others, both phases of the Northern Annular Mode and Pacific blocking. The regimes are maintained predominantly by transient eddy fluxes of low-pass-filtered anomalies. It is demonstrated how the dynamical description of the slow process switching between the regimes can be acquired from the analysis results, and an investigation of the resulting simplified dynamical model with respect to predictability is performed. A predictability study shows that a simple Markov model is able to predict the regimes up to six days ahead, comparable to the ability of high-resolution state-of-the-art numerical weather prediction models to accurately predict the onset and decay of blockings. The implications of the results for derivation of reduced models for extended-range predictability are discussed.

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Shumakov, D. V., D. I. Zybin, and M. A. Popov. "Physiological aspects of myocardial function improving during mechanical circulatory support." Transplantologiya. The Russian Journal of Transplantation 11, no. 4 (December 12, 2019): 311–19. http://dx.doi.org/10.23873/2074-0506-2019-11-4-311-319.

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In recent years, the mechanical support of blood circulation has proved to be a vital therapy for a terminal heart failure, and is considered as a "bridge" to transplantation or is used on a permanent basis in a patient who can not be included in the waiting list for a donor organ. Recent studies of the critical heart failure treatment during an assist device in situ have shown the myocardial recovery at the molecular and cellular levels. However, the transition of these changes to a functionally stable recovery of the heart function, which would allow the long-term results to be achieved without a heart transplant or switching off the mechanical support, is now rather an exception to the rule. At this time, the cause of the discrepancy between the high rate of recovery at the cellular and molecular levels and the low rate of cardiac function recovery remains poorly understood. Patients with chronic progressive heart failure can demonstrate the normalization of many structural myocardial abnormalities after a mechanical support that is actually a reverse remodeling. However, the reverse remodeling is not always considered equivalent to clinical recovery. The aim of this research is to study a significant improvement in the structure and function of the myocardium during the mechanical support of blood circulation.

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Peytavin, Axel, Bruno Sainte-Rose, Gael Forget, and Jean-Michel Campin. "Ocean Plastic Assimilator v0.2: assimilation of plastic concentration data into Lagrangian dispersion models." Geoscientific Model Development 14, no. 7 (July 30, 2021): 4769–80. http://dx.doi.org/10.5194/gmd-14-4769-2021.

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Abstract. A numerical scheme to perform data assimilation of concentration measurements in Lagrangian models is presented, along with its first implementation called Ocean Plastic Assimilator, which aims to improve predictions of the distributions of plastics over the oceans. This scheme uses an ensemble method over a set of particle dispersion simulations. At each step, concentration observations are assimilated across the ensemble members by switching back and forth between Eulerian and Lagrangian representations. We design two experiments to assess the scheme efficacy and efficiency when assimilating simulated data in a simple double-gyre model. Analysis convergence is observed with higher accuracy when lowering observation variance or using a circulation model closer to the real circulation. Results show that the distribution of the mass of plastics in an area can effectively be improved with this simple assimilation scheme. Direct application to a real ocean dispersion model of the Great Pacific Garbage Patch is presented with simulated observations, which gives similarly encouraging results. Thus, this method is considered a suitable candidate for creating a tool to assimilate plastic concentration observations in real-world applications to estimate and forecast plastic distributions in the oceans. Finally, several improvements that could further enhance the method efficiency are identified.

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Radіushin, D. О., О. А. Loskutov, and P. V. Кіstruga. "Prophylaxis of cerebro-vascular complications while performance of aorto-coronary shunting in conditions of artificial blood circulation." Klinicheskaia khirurgiia 86, no. 6 (June 27, 2019): 14–18. http://dx.doi.org/10.26779/2522-1396.2019.06.14.

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Objective. To estimate the efficacy of application of vasodilator nitroglycerine on background of high volumic speed of perfusion for prophylaxis of the cerebral vessels microembolism while performance of the aorto-coronary shunting (ACSH) operations in conditions of artificial blood circulation. Маterials and methods. The investigation was conducted in 72 patients, suffering the ischemic heart disease, to whom aorto-coronary shunting operation was accomplished in conditions of artificial blood circulation in the Odessa Regional Clinical Hospital. Median age of the patients have constituted (67.3 ± 5.2) yrs old, median body mass index - (27.4 ± 5.2) kg/m2, average duration of the operation - (269.4 ± 7.8) min, including the artificial blood circulation stage - (145 ± 4.5) min. General statistical sampling of the patients examined was randomized in accordance to the comparison group (n=34) and the investigated (n=38) group. For prophylaxis of the air microembolism in patients of the comparison group before the artificial blood circulation apparatus switching on during 9 - 10 min nitroglycerine was infused in the dose 8 - 10 mcg/kg × min on background of high (120 - 130% from the calculated one) volumic speed of perfusion with support of median index of arterial pressure on the level 50 - 60 mm Hg. Іntraoperative monitoring of cerebral blood flow was done, using transtemporal access in accordance to standard procedure. Cognitive status of the patients was estimated with the help of verbal and nonverbal tests (day before and on the fifth postoperative day). Results. The investigation accomplished have revealed, that in all the patient the ACSH operation in conditions of artificial blood circulation was accompanied by microembolism in the system of cerebral blood flow of the discrete character. Іntraoperative creation in cerebral blood flow of more than 750 microemboli causes occurrence of a clinically significant lowering of the brain cognitive functions in early postoperative period. Application of nitroglycerine as a kind of peripheral vasodilator in the dose 8 - 10 mcg/kg × min on background of high (120 - 130% of the calculated) volumic speed of perfusion have caused the reduction of the cognitive dysfunction severity by 15 - 20%.

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Watanabe, Taro, and Yoshio Takei. "Environmental factors responsible for switching on the SO42− excretory system in the kidney of seawater eels." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 301, no. 2 (August 2011): R402—R411. http://dx.doi.org/10.1152/ajpregu.00624.2010.

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Eels are unique in that they maintain lower plasma SO42− concentration in SO42−-rich (∼30 mM) seawater (SW) than in SO42−-poor (<0.3 mM) freshwater (FW), showing drastic changes in SO42− regulation between FW and SW. We previously showed that the expression of renal SO42− transporter genes, FW-specific Slc13a1 and SW-specific Slc26a6a, changes profoundly after transfer of FW eels to SW, which results in the decrease in plasma SO42− concentration after 3 days in SW. In this study, we attempted to identify the environmental factor(s) that trigger the switching of SO42− regulation using changes in plasma and urine SO42− concentrations and expression of the transporter genes as markers. Transfer of FW eels to 30 mM SO42− or transfer of SW eels to SO42−-free SW did not change the SO42− regulation. Major divalent cations in SW, Mg2+ (50 mM) and Ca2+ (10 mM), were also ineffective, but 50 mM NaCl was effective for switching the SO42− regulation. Further analyses using choline-Cl and Na-gluconate showed that Cl− is a primary factor and Na+ is permissive for the Cl− effect. Since plasma SO42− and Cl− concentrations were inversely correlated, we injected various solutions into the blood and found that Cl− alone triggered the switching from FW to SW-type regulation. Furthermore, the inhibitor of Na-Cl cotransporter (NCC) added to media significantly impaired the expression of SW-specific Slc26a6a in 150 mM NaCl. In summary, it appears that Cl− ions in SW are taken up into the circulation via the NCC together with Na+, and the resultant increase in plasma Cl− concentration enhances SO42− excretion by the kidney through downregulation of absorptive Slc13a1 and upregulation of excretory Slc26a6a, resulting in low plasma SO42− concentration in SW.

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Bogaerts, Bert, Raf Winand, Julien Van Braekel, Wesley Mattheus, Sigrid C. J. De Keersmaecker, Nancy H. C. Roosens, Kathleen Marchal, Kevin Vanneste, and Pieter-Jan Ceyssens. "Phylogenomic Investigation of Increasing Fluoroquinolone Resistance among Belgian Cases of Shigellosis between 2013 and 2018 Indicates Both Travel-Related Imports and Domestic Circulation." Microorganisms 9, no. 4 (April 6, 2021): 767. http://dx.doi.org/10.3390/microorganisms9040767.

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Shigellosis is an acute enteric infection caused mainly by the species Shigella flexneri and Shigella sonnei. Since surveillance of these pathogens indicated an increase in ciprofloxacin-resistant samples collected in Belgium between 2013 and 2018, a subset of 148 samples was analyzed with whole genome sequencing (WGS) to investigate their dispersion and underlying genomic features associated with ciprofloxacin resistance. A comparison between observed phenotypes and WGS-based resistance prediction to ciprofloxacin revealed perfect correspondence for all samples. Core genome multi-locus sequence typing and single nucleotide polymorphism-typing were used for phylogenomic investigation to characterize the spread of these infections within Belgium, supplemented with data from international reference collections to place the Belgian isolates within their global context. For S. flexneri, substantial diversity was observed with ciprofloxacin-resistant isolates assigned to several phylogenetic groups. Besides travel-related imports, several clusters of highly similar Belgian isolates could not be linked directly to international travel suggesting the presence of domestically circulating strains. For S. sonnei, Belgian isolates were all limited to lineage III, and could often be traced back to travel to countries in Asia and Africa, sometimes followed by domestic circulation. For both species, several clusters of isolates obtained exclusively from male patients were observed. Additionally, we illustrated the limitations of conventional serotyping of S. flexneri, which was impacted by serotype switching. This study contributes to a better understanding of the spread of shigellosis within Belgium and internationally, and highlights the added value of WGS for the surveillance of this pathogen.

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Sharashidze, Vera, Raul G. Nogueira, Alhamza R. Al-Bayati, Jonathan A. Grossberg, and Diogo C. Haussen. "Balloon anchoring technique for thrombectomy in hostile craniocervical arterial anatomy." Journal of NeuroInterventional Surgery 12, no. 8 (February 3, 2020): 763–67. http://dx.doi.org/10.1136/neurintsurg-2019-015347.

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BackgroundCraniocervical catheter access in large vessel occlusion acute ischemic strokes can be challenging in cases of unfavorable aortic arch/cervical vascular anatomy, leading to lower recanalization rates, increased procedural time and worse clinical outcomes. We aim to demonstrate the feasibility of the balloon-anchoring technique (BAT) that can be attempted before switching to alternative access sites.MethodsRetrospective review of prospectively collected information on 11 patients in which two variants of the BAT (proximal anchoring: balloon guide catheter (BGC) is inflated to provide support for distal access; distal anchoring: compliant balloon is inflated in an intracranial artery to allow advancement of the support system) were utilized to facilitate craniocervical access due to failure of conventional maneuvers.ResultsTen patients had anterior and one patient had posterior circulation large vessel occlusions. Mean age was 81 years and 81% were females. Type 3 arches were found in 82% and a 9 French balloon guide catheter was used in 82%. Proximal anchoring with BGC was used in four cases while distal anchoring was used in seven patients to allow access to the target vessel, avoiding the need to puncture alternative access sites. Successful reperfusion (modified treatment in cerebral ischemia 2b-3) was achieved in all cases and no complications were observed.ConclusionBAT is safe and feasible. It can be considered as a rescue maneuver in order to avoid switching to a different access during thrombectomy in individuals with unfavorable aortic arch/craniocervical anatomy.

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Rossow, William B., Ademe Mekonnen, Cindy Pearl, and Weber Goncalves. "Tropical Precipitation Extremes." Journal of Climate 26, no. 4 (February 15, 2013): 1457–66. http://dx.doi.org/10.1175/jcli-d-11-00725.1.

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Abstract Classifying tropical deep convective systems by the mesoscale distribution of their cloud properties and sorting matching precipitation measurements over an 11-yr period reveals that the whole distribution of instantaneous precipitation intensity and daily average accumulation rate is composed of (at least) two separate distributions representing distinctly different types of deep convection associated with different meteorological conditions (the distributions of non-deep-convective situations are also shown for completeness). The two types of deep convection produce very different precipitation intensities and occur with very different frequencies of occurrence. Several previous studies have shown that the interaction of the large-scale tropical circulation with deep convection causes switching between these two types, leading to a substantial increase of precipitation. In particular, the extreme portion of the tropical precipitation intensity distribution, above 2 mm h−1, is produced by 40% of the larger, longer-lived mesoscale-organized type of convection with only about 10% of the ordinary convection occurrences producing such intensities. When average precipitation accumulation rates are considered, essentially all of the values above 2 mm h−1 are produced by the mesoscale systems. Yet today’s atmospheric models do not represent mesoscale-organized deep convective systems that are generally larger than current-day circulation model grid cell sizes but smaller than the resolved dynamical scales and last longer than the typical physics time steps. Thus, model-based arguments for how the extreme part of the tropical precipitation distribution might change in a warming climate are suspect.

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Kosenko, Roman, Andrei Blinov, Dmitri Vinnikov, and Andrii Chub. "Asymmetric snubberless current-fed full-bridge isolated DC-DC converters." Electrical, Control and Communication Engineering 14, no. 1 (July 1, 2018): 5–11. http://dx.doi.org/10.2478/ecce-2018-0001.

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Abstract This paper presents two isolated current-fed fullbridge DC-DC converters that can be used to interface a lower voltage source into a DC bus of higher voltage. The first topology uses a resonant circuit to force current redistribution between low-voltage-side transistors and a passive rectifier. The second topology utilizes an active rectifier with secondary modulation to achieve the same goal. The resonant circuit can be formed by using transformer leakage inductance and the parasitic capacitances of the switches. The converters feature soft switching of semiconductors over a wide range of operating conditions. This is achieved with decreased energy circulation when compared to existing topologies with symmetric control and with fewer semiconductors than in those with phase-shift control. The topologies can be implemented in renewable, supercapacitor, battery, fuel cell, and DC microgrid applications. Steady-state operation and design aspects of the converters are presented and verified experimentally with 400 W prototypes

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Lee, Myeong Soo, Sang-Yong Jeong, Yong-Heum Lee, Dong-Myong Jeong, Yoon-Gi Eo, and Su-Bok Ko. "Differences in Electrical Conduction Properties Between Meridians and Non-meridians." American Journal of Chinese Medicine 33, no. 05 (January 2005): 723–28. http://dx.doi.org/10.1142/s0192415x05003405.

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Therapy using the acupuncture meridian system is an important part of traditional Chinese medicine. The purpose of this study was to investigate the electrical conduction properties of the meridians. The current conduction and potential profiles were compared after switching the current direction in the Hegu (LI-4) and Quchi (LI-11) meridians and over a non-acupuncture point 1 cm from Quchi (LI-11) in 20 healthy subjects. Both meridians demonstrated significantly higher conductivity between Hegu (LI-4) and Quchi (LI-11) than between Hegu (LI-4) and the non-acupuncture point. The direction of current, peak frequency and absolute potential values in the direction Hegu (LI-4) to Quchi (LI-11) differed significantly from those in the direction Quchi (LI-11) to Hegu (LI-4). These results suggest that the conducting pathways are stronger in the meridians than in the non-meridians and that preferential conduction directions exist between two acupuncture points. These results are consistent with the theories of Qi-circulation and traditional Chinese medicine.

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Scheele, Camilla, and Christian Wolfrum. "Brown Adipose Crosstalk in Tissue Plasticity and Human Metabolism." Endocrine Reviews 41, no. 1 (October 15, 2019): 53–65. http://dx.doi.org/10.1210/endrev/bnz007.

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Abstract Infants rely on brown adipose tissue (BAT) as a primary source of thermogenesis. In some adult humans, residuals of brown adipose tissue are adjacent to the central nervous system and acute activation increases metabolic rate. Brown adipose tissue (BAT) recruitment occurs during cold acclimation and includes secretion of factors, known as batokines, which target several different cell types within BAT, and promote adipogenesis, angiogenesis, immune cell interactions, and neurite outgrowth. All these processes seem to act in concert to promote an adapted BAT. Recent studies have also provided exciting data on whole body metabolic regulation with a broad spectrum of mechanisms involving BAT crosstalk with liver, skeletal muscle, and gut as well as the central nervous system. These widespread interactions might reflect the property of BAT of switching between an active thermogenic state where energy is highly consumed and drained from the circulation, and the passive thermoneutral state, where energy consumption is turned off. (Endocrine Reviews 41: XXX – XXX, 2020)

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KOROSTOVTSEV, D. S., E. A. KORNIENKO, L. A. GALENKO, O. V. TRUSOVA, A. V. KAMAEV, and I. V. MAKAROVA. "GASTROINTESTINAL MANIFESTATIONS OF FOOD ALLERGY: PATHOGENESIS, CLINICAL FORMS AND CLUES TO THERAPY." Russian Journal of Allergy 11, no. 3 (December 15, 2014): 11–20. http://dx.doi.org/10.36691/rja488.

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Food allergies (fa), defined as an adverse immune response to food proteins, effect up to 3-5% of the popula- tion in westernized countries, and their prevalence appears to be rising. a variety of mechanisms underlie the allergic reactions, not all of them run through the IgE sensitisation. the absence of sIgE in peripheral circulation characterize a group of non-Ig-Emediated disorders, such as food protein-induced enterocolitis, enteropathy and prococolitis. In case of eosinophilic esophagitis, gastritis and enterocolitis IgE sensitization arises in nearly 50%, therefore these disorders are classified as mixed-type. In some cases of gastrointestinal fa local IgE production, when switching to IgE synthesis occurs only in one organ, have been proved. although systemic investigation of this phenomenon is still lacking. Immune inflammation coursed by food allergens can involve nearly all organs and systems. this review focuses on gastroenterological manifestations of food allergy, except of broad field of gluten intolerance that demands a separate thorough reviewing.

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Makowska, Kaja. "Young adult literature in translation: The state of research." Beyond Philology An International Journal of Linguistics, Literary Studies and English Language Teaching, no. 16/4 (December 11, 2019): 179–94. http://dx.doi.org/10.26881/bp.2019.4.07.

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The aim of the article is to examine the concept of young adult literature, provide its historical timeframe, identify its key components, and, finally, discuss young adult literature in translation by presenting the state of research on the topic. After analysing the concept of a young adult, the article moves on to provide a brief summary of adolescent fiction’s history, concluding that J. D. Salinger’s The Catcher in the Rye and S. E. Hinton’s The Outsiders largely contributed to the recognition of the genre. The paper mentions characteristic style choices employed by the authors of young adult fiction, the most prominent being the blend of registers or ‘code-switching’ between teen and adult speech, as acknowledged by Penelope Eckert and Chuck Wendig. Code-switching constitutes one of the main translation problems and is discussed at large in two compelling papers on the topic of young adult literature translation, namely Translating Young Adult Literature. The High Circulation Rate of Youth Language and Other Related Translation Problems in “The Catcher in the Rye” and “The Outsiders” by Saskia Tempert and Translating Young Adult Literature: Problems and Strategies. John Green`s “An Abundance of Katherines” by Loana Griguta. Both dissertations analyse the language of adolescent novels (in the twentieth and the twenty first century) and devise a list of strategies dedicated to adequately rendering English source versions into Dutch and Romanian, respectively. These writings indicate a growing interest in the field of young adult literature translation. The article expresses the hope that more scholars will elaborate on the topic.

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Powell, J. J., R. Jugdaohsingh, and R. P. H. Thompson. "The regulation of mineral absorption in the gastrointestinal tract." Proceedings of the Nutrition Society 58, no. 1 (February 1999): 147–53. http://dx.doi.org/10.1079/pns19990020.

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The absorption of metal ions in the mammalian single-stomached gut is fortunately highly selective, and both luminal and tissue regulation occur. Initially, assimilation of metal ions in an available form is facilitated by the intestinal secretions, chiefly soluble mucus (mucin) that retards hydrolysis of ions such as Cu, Fe and Zn. Metal ions then bind and traverse the mucosally-adherent mucus layer with an efficiency M+> M2+> M3+. At the mucosa Fe3+is probably uniquely reduced to Fe2+, and all divalent cations (including Fe2+) are transported by a membrane protein (such as divalent cation transporter 1) into the cell. This minimizes absorption of toxic trivalent metals (e.g. A13+). Intracellular metal-binding molecules (such as mobilferrin) may be present at the intracellular side of the apical membrane, anchored to a transmembrane protein such as an integrin complex. This mobilferrin would receive the metal ion from divalent cation transporter 1 and, with part of the integrin molecule, transport the metal to the cytosol for safe sequestration in a larger complex such as ferritin or‘paraferritin’. β2-Microglobulin and HFE (previously termed human leucocyte antigen H) may be involved in stabilizing metal mobilferrin-integrin to form this latter complex. Finally, a systemic metal-binding protein such as transferrin may enter the antiluminal (basolateral) side of the cell for binding of the sequestered metal ion and delivery to the circulation. Regulatory proteins, such as HFE, may determine the degree of ion transport from intestinal cells to the circulation. Gradients in pH and perhaps pCa or even pNa could allow the switching of ions between the different transporters throughout this mechanism.

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Journal articles on the topic 'Circulation switching'

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