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1
Mamirova, Malikaxon Xusravjon qizi. "THE WAYS OF CONSTRUCTING ITEMS IN READING TESTS." EURASIAN JOURNAL OF ACADEMIC RESEARCH 2, no. 4 (2022): 13–18. https://doi.org/10.5281/zenodo.6468362.
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In this article ways of constructing items in reading tests are demonstrated. The investigation of the effect of item test characteristics on the difficulty of reading comprehension item often involves an analysis of various variables including passage features, question type features and question format variables.The study is based on describing the process of developing an academic reading ability test undertaken as a class project and to evaluate its authenticity. The basic purpose of the test is to develop the ability of designing and developing a language test of the students of a class of English language teaching. Thus, in this way along with the learning of the principles of language testing and assessment, the students have also been given a practical experience of designing and developing a test.
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Belserene, Emilia Pisani. "Moving Through The Instability Strip." International Astronomical Union Colloquium 139 (1993): 419. http://dx.doi.org/10.1017/s025292110011810x.
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The purpose: To look at period changes in pulsating variables from the point of view of stellar evolution. Is there evidence of systematic, slow changes that might be caused by the changes in mean density during passage across the Instability Strip?The data: O – C diagrams for 67 RR Lyrae stars and Cepheids by student assistants at the Maria Mitchell Observatory, and for 88 northern Cepheids by L. SzabadosThe method: Least-squares lines and parabolae (unless the O – C diagram shows that the period has changed in both directions). The rate of change of period comes from the coefficient of the square term in the parabola. The principal feature of these analyses is that the rate is taken to be non-zero only if the parabola is significantly better than the linear fit, at the 2-sigma level.
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Sun, Yunpeng, Rafael Mendoza-Arriaga, and Vadim Linetsky. "Marshall–Olkin distributions, subordinators, efficient simulation, and applications to credit risk." Advances in Applied Probability 49, no. 2 (2017): 481–514. http://dx.doi.org/10.1017/apr.2017.10.
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Abstract In the paper we present a novel construction of Marshall–Olkin (MO) multivariate exponential distributions of failure times as distributions of the first-passage times of the coordinates of multidimensional Lévy subordinator processes above independent unit-mean exponential random variables. A time-inhomogeneous version is also given that replaces Lévy subordinators with additive subordinators. An attractive feature of MO distributions for applications, such as to portfolio credit risk, is its singular component that yields positive probabilities of simultaneous defaults of multiple obligors, capturing the default clustering phenomenon. The drawback of the original MO fatal shock construction of MO distributions is that it requires one to simulate 2n-1 independent exponential random variables. In practice, the dimensionality is typically on the order of hundreds or thousands of obligors in a large credit portfolio, rendering the MO fatal shock construction infeasible to simulate. The subordinator construction reduces the problem of simulating a rich subclass of MO distributions to simulating an n-dimensional subordinator. When one works with the class of subordinators constructed from independent one-dimensional subordinators with known transition distributions, such as gamma and inverse Gaussian, or their Sato versions in the additive case, the simulation effort is linear in n. To illustrate, we present a simulation of 100,000 samples of a credit portfolio with 1,000 obligors that takes less than 18 seconds on a PC.
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Horwitz, Rachel M., Alex E. Hay, William J. Burt, Richard A. Cheel, Joseph Salisbury, and Helmuth Thomas. "High-frequency variability of CO<sub>2</sub> in Grand Passage, Bay of Fundy, Nova Scotia." Biogeosciences 16, no. 2 (2019): 605–16. http://dx.doi.org/10.5194/bg-16-605-2019.
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Abstract. Assessing changes in the marine carbon cycle arising from anthropogenic CO2 emissions requires a detailed understanding of the carbonate system's natural variability. Coastal ecosystems vary over short spatial and temporal scales, so their dynamics are not well described by long-term and broad regional averages. A year-long time series of pCO2, temperature, salinity, and currents is used to quantify the high-frequency variability of the carbonate system at the mouth of the Bay of Fundy, Nova Scotia. The seasonal cycle of pCO2 is modulated by a diel cycle that is larger in summer than in winter and a tidal contribution that is primarily M2, with amplitude roughly half that of the diel cycle throughout the year. The interaction between tidal currents and carbonate system variables leads to lateral transport by tidal pumping, which moves alkalinity and dissolved inorganic carbon (DIC) out of the bay, opposite to the mean flow in the region, and constitutes a new feature of how this strongly tidal region connects to the larger Gulf of Maine and northwest Atlantic carbon system. These results suggest that tidal pumping could substantially modulate the coastal ocean's response to global ocean acidification in any region with large tides and spatial variation in biological activity, requiring that high-frequency variability be accounted for in assessments of carbon budgets of coastal regions.
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Prasanta, Biswas. "Mathematical Differential Solution of Flow and Head loss in the Flow correction and Design of Distribution Network of Water Supply." International Journal of Trend in Scientific Research and Development 2, no. 3 (2018): 2711–15. https://doi.org/10.31142/ijtsrd12923.
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This study has explained a method of solution of general flow problem by mathematics. The flow problem is the Darcy Weisbach formula of the head loss, i.e., HL=KQx. This equation has been transformed into the Leibnitz's form of the differential equation and then solved subsequently, considering suitable functionary variables for the derivation as applicable. This way of solution takes the feature of inner variables of a problem to limelight which might not achieve the breakthrough instead by any other way of the available solution in mathematics. Ultimately, in this study, the flow correction has got to be a different dimension by the mode of application of mathematics. With the final form of the differential solution, the head loss estimation has been adjusted for the loops in a distribution network in order to get the given flows passing through the pipe loops made into the subsequent corrected values. Future scope of this study is enormous the following up of this study's initiative proceeding for the numerous subjective fields of concern and lastly not the least indeed, the further research on the outcomes determined in this study by such application of the mathematical passage to go to finding out its further implication. Prasanta Biswas "Mathematical Differential Solution of Flow & Head-loss in the Flow-correction & Design of Distribution Network of Water Supply" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: https://www.ijtsrd.com/papers/ijtsrd12923.pdf
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Trace, Jonathan, James Dean Brown, Gerriet Janssen, and Liudmila Kozhevnikova. "Determining cloze item difficulty from item and passage characteristics across different learner backgrounds." Language Testing 34, no. 2 (2016): 151–74. http://dx.doi.org/10.1177/0265532215623581.
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Cloze tests have been the subject of numerous studies regarding their function and use in both first language and second language contexts (e.g., Jonz & Oller, 1994; Watanabe & Koyama, 2008). From a validity standpoint, one area of investigation has been the extent to which cloze tests measure reading ability beyond the sentence level. Using test data from 50 30-item cloze passages administered to 2,298 Japanese and 5,170 Russian EFL students, this study examined the degree to which linguistic features for cloze passages and items influenced item difficulty. Using a common set of 10 anchor items, all 50 tests were modeled in terms of person ability and item difficulty onto a single scale using many-faceted Rasch measurement ( k = 1314). Principle components analysis was then used to categorize 25 linguistic item- and passage-level variables for the 50 cloze tests and their respective items, from which three components for each passage- and item-level variables were identified. These six factors along with item difficulty were then entered into both a hierarchical structural equation model and a linear multiple regression to determine the degree to which difficulty in cloze tests could be explained separately by passage and item features. Comparisons were further made by looking at differences in models by nationality and by proficiency level (e.g., high and low). The analyses revealed noteworthy differences in mean item difficulties and in the variance structures between passage- and item-level features, as well as between different examinee proficiency groups.
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Kumar, Abhishek, and Meenakshi Bharkatiya. "A Review on Updates to Increase the Residence Time of Drug in the Stomach for Gastro Retentive Drug Delivery System." Indo Global Journal of Pharmaceutical Sciences 11, no. 02 (2021): 130–42. http://dx.doi.org/10.35652/igjps.2021.112008.
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Orally-administered controlled-release drug delivery systems are associated with the shortcomings of relatively short residence times in the human stomach as well as highly variable gastrointestinal (GI) transit times. Thus, considerable intra-individual and inter-individual differences in the bioavailability of drugs are observable. There are numerous drug substances which may benefit from prolonged and controlled GI passage times. As a solution to the problem, gastroretentive drug delivery systems (GRDDS), which feature an enhanced gastric residence time (GRT), were developed. Several approaches are currently used including Floating Drug Delivery System (FDDS), swelling and expanding system, polymeric bioadhesive systems, modified-shape systems, high density system and other delayed gastric emptying devices. The drugs having absorption window in the upper part of Gastro Intestinal Tract (GIT) have enhanced bioavailability when formulated through these techniques. The recent technological development for enhancing GRT including the physiological and formulation variables affecting gastric retention, patented delivery systems, approaches to design single-unit and multiple-unit floating systems, and their classification and formulation aspects are covered in detail. Despite the extensive research performed in the field of GRDDS, the development, the production, and the evaluation of floating devices are still challenging. The purpose of writing this review was to compile recent literature on pharmaceutical approaches used in enhancing the Gastric Residence Time (GRT). Enhancing the GRT may explore new potentials of stomach as drug-absorbing organ. © 2020 iGlobal Research and Publishing Foundation. All rights reserved.
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Pan, Hong, Jie Yang, Yang Yu, Yuan Zheng, Xiaonan Zheng, and Chenyang Hang. "Intelligent Low-Consumption Optimization Strategies: Economic Operation of Hydropower Stations Based on Improved LSTM and Random Forest Machine Learning Algorithm." Mathematics 12, no. 9 (2024): 1292. http://dx.doi.org/10.3390/math12091292.
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The economic operation of hydropower stations has the potential to increase water use efficiency. However, there are some challenges, such as the fixed and unchangeable flow characteristic curve of the hydraulic turbines, and the large number of variables in optimal load distribution, which limit the progress of research. In this paper, we propose a new optimal method of the economic operation of hydropower stations based on improved Long Short-Term Memory neural network (I-LSTM) and Random Forest (RF) algorithm. Firstly, in order to accurately estimate the water consumption, the LSTM model’s hyperparameters are optimized using improved particle swarm optimization, and the I-LSTM method is proposed to fit the flow characteristic curve of the hydraulic turbines. Secondly, the Random Forest machine learning algorithm is introduced to establish a load-distribution model with its powerful feature extraction and learning ability. To improve the accuracy of the load-distribution model, we use the K-means algorithm to cluster the historical data and optimize the parameters of the Random Forest model. A Hydropower Station in China is selected for a case study. It is shown that (1) the I-LSTM method fits the operating characteristics under various working conditions and actual operating characteristics of hydraulic turbines, ensuring that they are closest to the actual operating state; (2) the I-LSTM method is compared with Support Vector Machine (SVM), Extreme Learning Machine (ELM) and Long Short-Term Memory neural network (LSTM). The prediction results of SVM have a large error, but compared with ELM and LSTM, MSE is reduced by about 46% and 38% respectively. MAE is reduced by about 25% and 21%, respectively. RMSE is reduced by about 27% and 24%, respectively; (3) the RF algorithm performs better than the traditional dynamic programming algorithm in load distribution. With the passage of time and the increase in training samples, the prediction accuracy of the Random Forest model has steadily improved, which helps to achieve optimal operation of the units, reducing their average total water consumption by 1.24%. This study provides strong support for the application of intelligent low-consumption optimization strategies in hydropower fields, which can bring higher economic benefits and resource savings to renewable energy production.
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Gattulli, Lofrano, Paolone, and Potenza. "Measured properties of structural damping in railway bridges." Journal of Civil Structural Health Monitoring 9 (October 14, 2019): 639–53. https://doi.org/10.5281/zenodo.6671677.
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Dissipative properties of a structural system are difficult to be characterized in real structure. Nevertheless, damping features may be dominant in several operating conditions of railway bridges influencing fatigue life or passenger comfort during train passage. Observations treating real data acquired in operational condition on steel and concrete railway bridges belonging to the Italian network permits to highlight dissipative sources and features. Consequently, linearized modal damping ratios are evaluated through a recursive process on the acceleration signals acquired before, during and after train passages and/or in environmental conditions. Stochastic Subspace Identification has been used to identify state-space dynamical models able to reproduce the vibrations. Through these models, characterized by an increasing number of state-space variables, it is possible to extract modal damping ratios. A mechanical interpretation of damping characteristics is pursued through the evaluation of the differences with respect to a classical Rayleigh proportional damping matrix of the viscous matrix belonging to the identified state-space models determined through the system spectral features. A non-proportional damping index is presented as a basis to determine the influence of different sources of non-proportionality in the damping matrix (as the ballast layer under the track) and to justify the high value of damping observed in specific experimental campaigns.
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Binding, Paul, D. R. Farenick, and Chi-Kwong Li. "A Dilation and Norm in Several Variable Operator Theory." Canadian Journal of Mathematics 47, no. 3 (1995): 449–61. http://dx.doi.org/10.4153/cjm-1995-025-5.
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AbstractFor every m-tuple of operators acting on a Hilbert space, it is shown that there exists a common dilation of these operators to mcommuting normal operators on some larger Hilbert space. We then introduce a norm on the m-fold cartesian product of ℬ(ℋ) that is defined to be, for a given w-tuple, the infimum of the joint spectral radii of all joint normal dilations of the m operators. This norm has several good features, one of which is that it is invariant under the passage to adjoints.
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Kazanko, Alexander, and Olga Penkina. "PROPAGATION OF MECHANIC WAVE IN TWO-DIMENSION STRATIFIED MEDIUM." Collection of Scientific Works of the Ukrainian State University of Railway Transport, no. 205 (September 29, 2023): 25–36. http://dx.doi.org/10.18664/1994-7852.205.2023.288814.
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The principle of emergence encourages us to look for new properties in future materials as a result of structuring of constituent elements, and mostly we are talking about non-obvious structuring. For example, understanding and simulating isotropy is on the way to robustness against internal vibrations. Structurality itself is a characteristic feature of the world around a person (protein molecules, crystal lattices, etc.). However, the variety of natural structures is so numerous that directly studying them to identify new properties appears to be quite a difficult task. Therefore, to a certain extent, the principle of emergence supposedly contrasts the need to copy or imitate natural structures with the ability to carry out inventions. Just as a wide variety of patterns are formed in an optical kaleidoscope thanks to 2 or 3 optical elements, the principle of emergence gives reason to expect that as a result of structuring only a few components of the future environment, new properties can be obtained. The development of technology, in particular, 3D printing, opens up opportunities to look at the methodology of structuring the environment in a new way. If, in addition, this process is relatively economic, then empirically, by carrying out structuring, it is possible to obtain experimental laboratory samples. Today they are talking about the possibility of achieving such effects as lensing of mechanical waves precisely thanks to emergent properties. The corresponding devices promise to find application, for example, in ultrasound diagnostics in medicine (Assoc. Prof. J. Memoli, University of Sussex, UK). The paper considers the problem of the propagation of mechanical waves in a folding periodic two-layer medium - a flat model. For such a medium, a wave equation is written and solved by the method of separation of variables. Such an equation turns out to be a linear differential equation with periodic piecewise-stable coefficients. From the basic theory of differential equations with periodic coefficients (Floquet theory), the method of transfer matrices (a method for calculating the passage of waves through multilayer media) is well known, which makes it possible to obtain a composite condition for the solvability of the wave equation. The work develops an approach to obtaining solvability conditions (constructing a dispersion equation) along with the classical method of transfer matrices. The proposed approach is in a certain sense equivalent to the transfer matrix method, however, it has some remarkable differences, in particular, it provides a rigorous mathematical basis for the transition to media with a finite number of layers.
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Monteiro, Vanessa. "Convective boundary layer characterization in the Amazon rainforest before and after the passage of Mesoscale convective systems." Ciência e Natura 42 (August 28, 2020): e2. http://dx.doi.org/10.5902/2179460x45217.
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This study describes thermodynamic variables (e.g., temperature and humidity) of the atmospheric convective boundary layer (CBL) and its growth rates preceding and following the passage of mesoscale convective systems (MCSs) in the Amazon rainforest. Using the data set provided by GoAmazon 2014/15, this study will address its objectives through the evaluation of case studies and an ensemble of days when there was the passage of MCSs. The results show that the convective boundary layer experiences reductions in the equivalent potential temperature within 2 to 8K and in the specific humidity up to 2 g kg-1 after the passage of a MCS, due to the cold and dry air brought to the surface by storms downdrafts. These two variables in addition to others (e.g., energy fluxes) are responsible for the low growth rates of the convective boundary layer, that were reduced by 100 m h-1 in the following two hours after the rainfall ceases, when compared to undisturbed conditions. Nonetheless, this work provides a quantitative evaluation of the thermodynamic features of the convective boundary layer under the passage of mesoscale convective systems in the Amazon rainforest.
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Auscavitch, Steven R., and Rhian G. Waller. "Biogeographical patterns among deep sea megabenthic communities across the Drake Passage." Antarctic Science 29, no. 6 (2017): 531–43. http://dx.doi.org/10.1017/s0954102017000256.
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AbstractBiogeographical patterns among deep sea benthic communities in the Drake Passage remain poorly understood as a consequence of poor sampling resolution and the spatial remoteness of many sea floor features. Hard-bottom features, including at least 20 seamounts, remain uncharacterized with respect to their benthic megafaunal community assemblages. Here, we present community assemblage patterns from several locations across the Drake Passage to better understand the faunal relationships between deep sea floor communities in the region. Towed camera surveys were conducted on nine topographical features ranging from shelf environments on the southern Chilean Margin, the western Antarctic Peninsula shelf and seamounts in the central Drake Passage. These are the first quantitative measurements of megafaunal abundance at two seamount complexes in the central Drake Passage and multivariate analyses are used to examine the factors influencing species distributions. Three biogeographical groupings were identified based on species assemblages and environmental variables specific to major water mass boundaries in the region: sub-Antarctic Mode Water (318–523 m), Antarctic Intermediate Water (504–1128 m) and Circumpolar Deep Water (1837–3034 m). Further examination of megafaunal associations between sea floor structures may provide clues as to how sub-Antarctic communities are connected throughout the greater Southern Ocean.
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Rosiński, Adam. "Variable Properties of Auditory Scene Analysis in Music." Arts 14, no. 1 (2025): 19. https://doi.org/10.3390/arts14010019.
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This article explores the variable properties of auditory image analysis during the perception of musical works, which are influenced by the specific elements to which the listener directs their attention. Traditional analyses of musical compositions typically involve brief comparisons with auditory phenomena described in scientific studies, such as those by A.S. Bregman. However, these analyses are often limited, offering only a narrow perspective on the works. In contrast, the approach presented in this article extends the theories and experiments developed by Bregman and others, providing a more comprehensive understanding of entire compositions or selected sections rather than focusing solely on isolated passages. This broader framework enhances auditory image analysis and serves as a foundation for further research. The expanded analysis integrates within music theory, enabling a deeper exploration of musical structures, particularly in the context of perceiving multilayered music where multiple sound sources may share similar acoustic features. The author illustrates how acoustic and perceptual factors contribute to complex mental representations through graphic and musical examples. To substantiate the claims, classical works by composers such as F. Chopin, A. Guilmant, and J.S. Bach are analysed, further highlighting the variable properties of auditory image analysis.
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Widmer, Giovanni, Laurie Tchack, Cynthia L. Chappell та Saul Tzipori. "Sequence Polymorphism in the β-Tubulin Gene Reveals Heterogeneous and Variable Population Structures inCryptosporidium parvum". Applied and Environmental Microbiology 64, № 11 (1998): 4477–81. http://dx.doi.org/10.1128/aem.64.11.4477-4481.1998.
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ABSTRACT Restriction fragment length polymorphism (RFLP) analysis of isolates of Cryptosporidium parvum has revealed two subgroups, termed H and C. The limited resolution of the RFLP method precludes an in-depth study of the genetic structure of C. parvum populations. Published C. parvum restriction polymorphisms lie within protein-coding regions known to be more homogeneous than noncoding sequences. To better assess the degrees of heterogeneity between and within C. parvum isolates, sequence polymorphism in the β-tubulin intron, the only C. parvum intron described to date, was investigated. In contrast to the two genotypes distinguished by multilocus RFLP, several alleles were detected by sequence and RFLP analysis of the β-tubulin intron and adjacent exon 2. Isolates carrying different β-tubulin alleles were found. Significantly, one of the β-tubulin alleles present in two geographically unrelated isolates combined features of C- and H-type isolates, suggesting that it might have arisen from a recombination event. A comparison of multiple samples of a calf-propagated laboratory isolate showed that the ratio of different β-tubulin alleles fluctuated during serial passage.
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Scott, J. N., and W. L. Hankey. "Navier–Stokes Solutions of Unsteady Flow in a Compressor Rotor." Journal of Turbomachinery 108, no. 2 (1986): 206–15. http://dx.doi.org/10.1115/1.3262039.
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In order to achieve more accurate predictions of unsteady flow in a transonic compressor rotor an existing numerical approach has been modified by incorporating a turbulence model. The computations are performed by solving the complete time-dependent compressible Navier–Stokes equations using MacCormack’s explicit finite difference algorithm. These equations are solved for the flow through two adjacent rotor blades at a streamsurface near the blade tip subjected to the wakes emitted from upstream stators. At this radial location the flow enters the blade passage at an absolute Mach number of 0.66. The high blade curvature at this radial location produces a large region of separated flow on the suction surface with laminar flow. To more accurately resolve the features of this flow separation the Baldwin–Lomax algebraic eddy-viscosity turbulence model is incorporated into the numerical procedure in regions near the blade surface. The unsteady flow features are represented at the inflow boundary through the use of characteristic variables involving the upstream and downstream running Riemann invariants and the entropy variation expressed in terms of the total pressure profile. At the outflow boundary the concept of a “second throat” or choke point is implemented in conjunction with supersonic outflow conditions. The results are compared with numerical results obtained without the use of a turbulence model (laminar) for a single blade passage. Improved agreement with limited experimental data is also noted.
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Manterola, Carlos, Josue Rivadeneira, Claudio Rojas-Pincheira, et al. "Cholangiohydatidosis. Clinical features, postoperative complications and hospital mortality. A systematic review." PLOS Neglected Tropical Diseases 18, no. 3 (2024): e0011558. http://dx.doi.org/10.1371/journal.pntd.0011558.
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Background Cholangiohydatidosis (CH) is an evolutionary complication of hepatic cystic echinococcosis, associated with increased morbidity and mortality. The aim of this study was to describe the available evidence regarding clinical characteristics of CH, postoperative complications and hospital mortality. Methodology/Principal findings Systematic review. Studies related to CH with no language or publication restriction were included. Sensitive searches were performed in Trip Database, SciELO, BIREME-BVS, WoS, PubMed, EMBASE and SCOPUS. MeSH and free terms were used, including articles up to April 2023. The main outcome variables were postoperative complications and hospital mortality; the secondary ones were publication year, origin and design of primary studies, main clinical manifestation, anatomical location and type of cysts, hospital stay, surgical procedure performed, reinterventions; and methodological quality of primary studies, which was assessed using MInCir-T and MInCir-P scales. Descriptive statistics, calculation of weighted averages and their comparison by least squares logistic regression were applied. 446 studies were retrieved from the searches performed, 102 of which met the inclusion and exclusion criteria. The studies analyzed represent 1241 patients. The highest proportion of articles was published in the last decade (39.2%). Reports are mainly from Turkey (28.4%), Greece (9.8%), Morocco and Spain (8.8% each). With a weighted mean of 14.3 days of hospital stance; it was verified that 26.2% of patients developed postoperative complications (74,3% Clavien y Dindo III y IV), 6.7% needed re-interventions, and 3.7% died. When comparing the variables age, postoperative complications, hospital mortality, and reinterventions in two periods of time (1982–2006 vs. 2007–2023), no statistically significant differences were found. When applying the MInCir-T and MInCir-P scales, the methodological quality of the primary studies was 9.6±1.1 and 14.5±4.3 points, respectively. Conclusion/Significance CH is associated with severe postoperative complications and significant hospital mortality, independent of the development of therapeutic support associated with the passage of time.
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Cheng, L., J. Zhu, and R. L. Sriver. "Global representation of tropical cyclone-induced short-term ocean thermal changes using Argo data." Ocean Science 11, no. 5 (2015): 719–41. http://dx.doi.org/10.5194/os-11-719-2015.
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Abstract. Argo floats are used to examine tropical cyclone (TC) induced ocean thermal changes on the global scale by comparing temperature profiles before and after TC passage. We present a footprint method that analyzes cross-track thermal responses along all storm tracks during the period 2004–2012. We combine the results into composite representations of the vertical structure of the average thermal response for two different categories: tropical storms/tropical depressions (TS/TD) and hurricanes. The two footprint composites are functions of three variables: cross-track distance, water depth and time relative to TC passage. We find that this footprint strategy captures the major features of the upper-ocean thermal response to TCs on timescales up to 20 days when compared against previous case study results using in situ measurements. On the global scale, TCs are responsible for 1.87 PW (11.05 W m−2) of heat transfer annually from the global ocean to the atmosphere during storm passage (0–3 days). Of this total, 1.05 ± 0.20 PW (4.80 ± 0.85 W m−2) is caused by TS/TD and 0.82 ± 0.21 PW (6.25 ± 1.5 W m−2) is caused by hurricanes. Our findings indicate that ocean heat loss by TCs may be a substantial missing piece of the global ocean heat budget. Changes in ocean heat content (OHC) after storm passage are estimated by analyzing the temperature anomalies during wake recovery following storm events (4–20 days after storm passage) relative to pre-storm conditions. Results indicate the global ocean experiences a 0.75 ± 0.25 PW (5.98 ± 2.1 W m−2) heat gain annually for hurricanes. In contrast, under TS/TD conditions, the ocean experiences 0.41 ± 0.21 PW (1.90 ± 0.96 W m−2) ocean heat loss, suggesting the overall oceanic thermal response is particularly sensitive to the intensity of the event. The ocean heat uptake caused by all storms during the restorative stage is 0.34 PW.
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Emmenegger, Tamara, Silke Bauer, Steffen Hahn, Susanne B. Müller, Fernando Spina, and Lukas Jenni. "Blood parasites prevalence of migrating passerines increases over the spring passage period." Journal of Zoology 306, no. 1 (2018): 23–27. https://doi.org/10.5281/zenodo.3906320.
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<strong>Abstract</strong> Whether long‐distance animal migration facilitates or hampers pathogen transmission depends on how infections affect the routes and timing of migrating hosts. If an infection directly or indirectly impedes migratory flight capacity, infected individuals lag behind their uninfected conspecifics. Although such temporal segregation can limit parasite transmission and thus play an important role for host–parasite interactions, empirical evidence remains scarce. Here, we investigated haemosporidians – blood parasites commonly infecting birds – in four passerine species on spring passage and linked infection status to passage date. As a step towards identifying the mechanisms behind infection‐related delays, we incorporated sets of individual, energetic, haematological and biometric variables into the analysis. Haemosporidian prevalence virtually doubled between birds sampled at the beginning of the passage period with those sampled 1 month later. This indicates that infected individuals arrived later than uninfected individuals. Both the average prevalence and its increase over time varied among host species. In addition, the leucocyte counts of infected birds were elevated, suggesting that immune response may require resources which could otherwise be allocated to migratory flights. However, infection status was not related to any other variable such as body mass, energy stores, sex, age and feather length. Yet regardless of the underlying mechanisms, infection‐related differential timing might influence transmission and affect pathogen prevalence in wildlife populations year‐round.
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Burkette, Allison. "Constructing the (m)other: A-prefixing, stance, and the lessons of motherhood." Language in Society 42, no. 3 (2013): 239–58. http://dx.doi.org/10.1017/s0047404513000225.
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AbstractThe present study examines two unprompted versions of the same story, related by a mother and daughter in separate sociolinguistic interviews. Following a quantitative intraspeaker comparison of their use of grammatical features associated with Appalachian English within the entirety of their interviews, this study undertakes a close reading of the narratives (along with additional passages from the daughter) to demonstrate the manner in which the two women construct their identities as “mother” and as “other” through conversational narrative and the use of local dialect features. Specifically, this article addresses the use of regional grammatical variables to enact speaker stances toward mothering, focusing on two women's independent recollections of a single incident and how these narratives dialogically construct the (m)other. (Language variation, Appalachian English, stancetaking, motherhood)*
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Ibrahim, Olayinka Rasheed, Michael Abel Alao, and Muhammed Nurudeen Adeboye. "Clinical and Laboratory Predictors of Acute Kidney Injury in Childhood Severe Malaria." Journal of Nepal Paediatric Society 44, no. 1 (2024): 24–30. https://doi.org/10.60086/jnps1032.
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Introduction: Despite being responsible for the highest burden of global malaria infection, there are limited data on malaria-associated acute kidney injury (MAKI) among Nigerian children for informed decisions. This study described the incidence and predictors of malaria-associated AKI among a cohort of 541 children in northwestern Nigeria. Method: This was a retrospective review of malaria cases from 1st January 2019 to December 31, 2020. We extracted socio-demographics, clinical features, and laboratory parameters from the records of the children with confirmed cases of severe malaria. AKI was defined and staged according to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) criteria. We carried out bivariate analysis and entered variables that were significant into binary logistic regression in order to determine predictors of AKI. Result: Out of the 541 children, 208 (38.4%) had MAKI. Of the 208, 165 (79.3%) were in stage 1, 26 (12.5%) were in stage 2, and 17 (8.2%) were in stage 3. Clinical features associated with AKI included hypoxemia, respiratory distress, loss of consciousness, prostration, passage of dark-colored urine, and shock (p<0.05). Laboratory parameters associated with AKI included acidosis, leukocytosis, hyponatremia, and hyperkalemia (p<0.05). Factors that independently predicted AKI included the passage of dark-colored urine with an adjusted odds ratio (AOR)-3.853 (95% CI 2.417, 6.143), hyponatremia-AOR 2.346, (95% CI 1.287, 4.277), and hyperkalemia-AOR 3.122, (95% CI 1.031, 9.393). Conclusion: The incidence of malaria-associated AKI is high among children in northwestern Nigeria. The presence of dark-colored urine, hyponatremia, and hyperkalemia strongly predict the risk for AKI.
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Cheng, L., J. Zhu, and R. L. Sriver. "Global representation of tropical cyclone-induced ocean thermal changes using Argo data – Part 1: Methods and results." Ocean Science Discussions 11, no. 6 (2014): 2831–78. http://dx.doi.org/10.5194/osd-11-2831-2014.
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Abstract. Argo floats are used to examine tropical cyclone (TC)-induced ocean thermal changes on the global scale by comparing temperature profiles before and after TC passage. We present a footprint method that analyzes cross-track thermal responses along all storm tracks during the period 2004–2012. We combine the results into composite representations of the vertical structure of the average thermal response for two different categories: tropical storms/depressions (TS/TD) and hurricanes. The two footprint composites are functions of three variables: cross-track distance, water depth and time relative to TC passage. We find that this footprint strategy captures the major features of the upper-ocean thermal response to TCs on time scales up to 20 days when compared against previous case study results using in situ measurements. Further, TC effects are distinguishable from background sampling variability, but the significance of this result depends on differences in regional oceanic conditions and the intensity of the TC events. On the global scale, results indicate that hurricanes induce strong upwelling near the storm center, along with downwelling away from the storm, during the first 3 days after storm passage. We also find significant subsurface warming between 30 and 200 m depth for both hurricanes and TS/TDs. On average, the subsurface ocean response persists along storm tracks for up to 20 days down to 200 (400) m depth for TS/TD (Hurricanes), exhibiting peak warming of 0.4 °C at 60 m for hurricanes and 0.2 °C at 35 m for TS/TD. The footprint method shows a weak cooling response between 200 and 400 m, which is significant for Hurricanes but not for TS/TD.
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Freke, Grace Mercedes, Tiago Martins, Rosalind Jane Davies, et al. "De-Suppression of Mesenchymal Cell Identities and Variable Phenotypic Outcomes Associated with Knockout of Bbs1." Cells 12, no. 22 (2023): 2662. http://dx.doi.org/10.3390/cells12222662.
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Bardet–Biedl syndrome (BBS) is an archetypal ciliopathy caused by dysfunction of primary cilia. BBS affects multiple tissues, including the kidney, eye and hypothalamic satiety response. Understanding pan-tissue mechanisms of pathogenesis versus those which are tissue-specific, as well as gauging their associated inter-individual variation owing to genetic background and stochastic processes, is of paramount importance in syndromology. The BBSome is a membrane-trafficking and intraflagellar transport (IFT) adaptor protein complex formed by eight BBS proteins, including BBS1, which is the most commonly mutated gene in BBS. To investigate disease pathogenesis, we generated a series of clonal renal collecting duct IMCD3 cell lines carrying defined biallelic nonsense or frameshift mutations in Bbs1, as well as a panel of matching wild-type CRISPR control clones. Using a phenotypic screen and an unbiased multi-omics approach, we note significant clonal variability for all assays, emphasising the importance of analysing panels of genetically defined clones. Our results suggest that BBS1 is required for the suppression of mesenchymal cell identities as the IMCD3 cell passage number increases. This was associated with a failure to express epithelial cell markers and tight junction formation, which was variable amongst clones. Transcriptomic analysis of hypothalamic preparations from BBS mutant mice, as well as BBS patient fibroblasts, suggested that dysregulation of epithelial-to-mesenchymal transition (EMT) genes is a general predisposing feature of BBS across tissues. Collectively, this work suggests that the dynamic stability of the BBSome is essential for the suppression of mesenchymal cell identities as epithelial cells differentiate.
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Hsieh, Hung-Yen, Jia-Jang Hung, Yu-Huai Wang, and Wen-Tseng Lo. "Hydrographic characteristics and community structure of epipelagic mesozooplankton in the Dongsha (Pratas) Atoll, South China Sea." Marine and Freshwater Research 68, no. 12 (2017): 2228. http://dx.doi.org/10.1071/mf16247.
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The relationship between hydrographic features and the community structure of epipelagic mesozooplankton was examined among 10 stations of the water body within the Dongsha (Pratas) Atoll during April (spring), July (summer) and October (autumn) 2011. The hydrographic conditions of the Dongsha Atoll were likely influenced by air temperature and rainfall due to the semi-enclosed topography. Surface water was warm and less saline, particularly in autumn, apparently due to the passage of Typhoon Nalgae. The highest mean (±s.d.) abundance of mesozooplankton was recorded in spring (1204 ± 336individualsm–3) and the lowest was recorded in autumn (45 ± 9individualsm–3). Twenty-six major mesozooplankton groups were observed across the samples collected. Mesozooplankton communities were dominated by calanoid copepods, crab zoea, fish eggs and foraminiferans, which together comprised 86.01% of the total zooplankton catch. The absence of significant correlation between mesozooplankton abundance and chlorophyll-a concentration indicated that the temporal pattern of the mesozooplankton community seems to be more dependent on physical variables than on primary production.
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Нетесин, Evgeniy Netesin, Пусева, et al. "MORPHOLOGICAL CHARACTERISTICS OF RABBIT’S FOREARM BONES GRAFT AT THE STIMULATION OF BIOLOGICALLY ACTIVE POINTS." Бюллетень Восточно-Сибирского научного центра Сибирского отделения Российской академии медицинских наук 1, no. 1 (2016): 42–48. http://dx.doi.org/10.12737/21484.
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The article presents the study of features of formation and remodeling of distraction graft of rabbits’ forearm bones
 at the passage of transosseous elements through acupuncture points. The aim of the work was to develop and perform
 quantitative estimation of regenerative process at the healing of forearm bone fractures using morphometric researches.
 We studied morphofunctional changes of graft on different stages of ossification using morphoscopy and morphometry
 and compared their quantitative characteristics with the ones in intact bone. Used index systems of estimation of regeneration
 processes at the healing of forearm bone fractures allow to reveal larger degree of statistical significance
 of obtained results not only in comparison with intact bone but also in over the time of experiment. Using quantitative
 variables and index estimation of regenerative processes at the healing of forearm bone fractures allow not only to
 objectify character of their changes but also to predict variability of its value.
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Ward, Michael P., Thomas J. Benson, Jill Deppe, et al. "Estimating apparent survival of songbirds crossing the Gulf of Mexico during autumn migration." Proceedings of the Royal Society B: Biological Sciences 285, no. 1889 (2018): 20181747. http://dx.doi.org/10.1098/rspb.2018.1747.
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Many migratory bird species are declining, and the migratory period may limit populations because of the risk in traversing large geographical features during passage. Using automated radio-telemetry, we tracked 139 Swainson's thrushes ( Catharus ustulatus ) departing coastal Alabama, USA and crossing the Gulf of Mexico to arrive in the Yucatan Peninsula, Mexico during autumn. We estimated apparent survival and examined how extrinsic (weather variables and day of year) and intrinsic (fat load, sex and age) factors influenced survival using a mark-recapture approach. We also examined how favourability of winds for crossing the Gulf varied over the past 25 years. Fat load, day of year and wind profit were important factors in predicting which individuals survived crossing the Gulf. Survival estimates varied with wind profit and fat, but generally, fat birds departing on days with favourable wind profits had an apparent survival probability of greater than 0.90, while lean individuals with no or negative wind profits had less than 0.33. The proportion of favourable nights varied within and among years, but has increased over the last 25 years. While conservation strategies cannot improve extrinsic factors, they can provide opportunities for birds to refuel before crossing large geographical features through protecting and creating high-quality stopover sites.
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Gómez-Garrido, M., V. Bujarrabal, J. Alcolea, R. Soria-Ruiz, P. de Vicente, and J. F. Desmurs. "Very fast variations of SiO maser emission in evolved stars." Astronomy & Astrophysics 642 (October 2020): A213. http://dx.doi.org/10.1051/0004-6361/202037499.
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Context. Stars on the asymptotic giant branch (AGB) are long-period variables that present strong flux variations at almost all wavelengths, including the SiO maser lines. The periods of these variations are of 300–500 days in Mira-type stars and somewhat shorter in semi-regular variables. The variability of the SiO lines on short timescales has been investigated, but the data are inconclusive. Aims. We aim to study the time evolution of the SiO maser lines in Mira-type and semi-regular variables at short timescales. We also discuss the origin of the observed fast variations. Methods. We observed the SiO maser lines at 7 mm (28SiO v = 1,2 J = 1–0) and 3 mm (28SiO v = 1 J = 2–1) using the 40 m Yebes antenna and the 30 m IRAM telescope, respectively, with a minimum spacing of 1 day. We studied the semi-regular variables RX Boo and RT Vir and the Mira-type variables U Her, R LMi, R Leo, and χ Cyg. We performed a detailed statistical analysis of the variations on different timescales. Results. RX Boo shows strong and fast variations in the intensity of the different spectral features of the SiO lines at 7 and 3 mm. On a timescale of one day, we find variations of ≳10% in 25% of the cases. Variations of greater than ~50% are often found when the observations are separated by 2 or 3 days. A similar variation rate of the SiO lines at 7 mm is found for RT Vir, but the observations of this object are less complete. On the contrary, the variations of the SiO maser line intensity in the Mira-type variables are moderate, with typical variation rates around ≲10% in 7 days. This phenomenon can be explained by the presence of particularly small maser-emitting clumps in semi-regular variables, which would lead to a strong dependence of the intensity on the density variations due to the passage of shocks.
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Abubakar, Hadi Saadu, Muhammad Usman Kanoma, Umar Muhammad Umar, and Babangida Ahmad Magami. "Application of Passive Cooling Techniques in an Institutional Building; A Case Study of Mass Communication Department, Abdu-Gusau Polytechnic Talata Mafara." International Journal of Advanced Academic Research 10, no. 12 (2024): 13–26. https://doi.org/10.5281/zenodo.14584894.
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<em>This study aimed at identifying passive cooling techniques through extensive literature study that can be incorporated in an institutional building to make it energy efficient. The study also aimed at identifying changes in the design process that can affect energy efficiency in the mass communication design. It has analyzed the design features of typical mass communication buildings through a case study conducted in Abdu-Gusau polytechnic in Talata Mafara Zamfara state. However, in this research an attempt shall be made to evolve design solution with proper consideration of the climate of the site. The climatic variables directly affecting energy usage and user’s comfort such as; temperature, humidity, solar radiation and air movement, are to be studied because these are the five constituents of climate that are more important for the purposes of building design. Within the context of tropical climate, with regards to this proposal, the climatic data of the study area are collected and analyzed through case study. The aim of this research is to examine the application of passive cooling techniques in an institutional building that connects the approaches of climate responsiveness in providing thermal comfort. The analyzed data shall guide us on the selection of building materials, construction method, shape and orientation of building, size and location of fenestrations and the use of soft landscape elements. These are taken into cognizance by relevant case studies and literature review of building in various climatic regions across the globe with respect to adaptability and response to various environmental variables.</em>
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Sewify, Gamal Hassan, Khurram Javid, Muhammad Adeel, et al. "Blood Flow in Multi-Sinusoidal Curved Passages with Biomimetic Rheology: An Application of Blood Pumping." Mathematics 10, no. 9 (2022): 1579. http://dx.doi.org/10.3390/math10091579.
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The unsteady flow of biological liquid through non-uniform pumps under porosity impacts is considered. The Jeffrey fluid is used as blood in the current study, which is also characterized as viscoelastic fluid because of its dual characteristics: on the one hand, its viscosity in nature; on the other hand, its elastic effect. Rheological equations are framed in a curvilinear coordinates system, and porosity influences are simulated with the body force term in momentum equations. The flow system has been transformed from fixed to wave frame using a linear–mathematical transformation between these two frames. In the next mathematical steps, these transformed equations are given in non-dimensional form using physical variables. The system of PDE is reduced to an ODE under lubrication theory and long wavelength approximation. Solutions to reduced ordinary differential equations are obtained numerically in MATLAB software via a BVP4C scheme. The physical impacts of the involved parameters on flow features, such as curvature, porosity (Darcy’s number), non-uniformity, and viscoelastic parameters, have been visualized graphically. Multi-sinusoidal waves are used in the boundary wall of the curved pump for peristaltic pumping. The magnitude of velocity profile for a saw-tooth wave (trapezoidal wave) is larger (smaller) than all other natures of peristaltic waves. The larger intensity of Darcy’s number has a dynamic role in the reduction of peristaltic pumping, whereas the opposite behavior is noticed when increasing the non-uniform nature of a channel. A comparison between all multi-sinusoidal waves is also addressed. The results of the present research shall be very productive for the manufacture of peristaltic pumps for drug delivery and bio-medical systems.
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Abro, Afsheen, Rubina Ahmedani, Saima Naz Shaikh, Shehmeen Khan, Urooj Bhatti, and Andleeb Mumtaz Sodhar. "ABO Blood Grouping in Partial and Complete Hydatidiform Molar Pregnancy." Pakistan Journal of Medical and Health Sciences 16, no. 2 (2022): 928–30. http://dx.doi.org/10.53350/pjmhs22162928.
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Objective: The present study was conducted to analyze the correlation of ABO blood groups in pregnant mother’s suffering from partial and complete Hydatidiform mole (HM) reporting at our tertiary care hospital. Study Design: Observational study Place and Duration: Liaquat University Hospital, Hyderabad/Jamshoro from May 2018 to October 2018. Methods: The present observational study analyzed the ABO blood groups of diagnosed cases of partial and complete type HM reporting at the Department of Obstetrics and Gynecology. A sample of 100 pregnant women suffering from Partial and complete HM and of their husbands was studied by inclusion criteria. ABO blood groups of these patients were determined as A, B, AB and O groups. Blood samples were processed for complete blood counts. Tests were performed at the Diagnostic and Research Laboratory, Liaquat University Hospital Hyderabad by forward and reverse ABO blood typing. Severity of GTD was assessed by WHO index score. Statistical comparisons of continuous and categorical variables run on SPSS ver. 21.0 at 95% confidence interval (P≤0.05). Results: Clinical presenting features bleeding PV, pain, hyperemesis gravidarum, grape like vesicles passage PV, no fetal heart sound, ovarian enlargement and hyperthyroidism. Partial and complete Hydatidiform mole was common in blood group A noted in 53 and 13 respectively. While Partial and complete Hydatidiform mole in blood group O was noted in 20 and 8 patients respectively (P=0.0001). The β–hCG ranged from 50,000 to 10, 00,000 mIU/mL. Conclusion: It is concluded, the hydatidiform mole proves strong association with blood groups A and O. Pregnant women complaining of bleeding PV, hyperemesis gravidarum, grape like vesicles passage with blood group A and O should be thoroughly investigated to minimize the maternal health risk. Keywords: Hydatidiform mole, Molar pregnancy, ABO blood groups
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Liu, Mingjun, Zhenjiu Zhang, Zhuoming Liang, et al. "New Insights into Flow for a Low-Bypass-Ratio Transonic Fan with Optimized Rotor." Energies 16, no. 21 (2023): 7230. http://dx.doi.org/10.3390/en16217230.
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In this paper, a three-dimensional aerodynamics optimization system is built and applied to optimize a rotor blade to balance the conflicts between stall margin, total pressure ratio, adiabatic efficiency, and mass flow rate for the high-loading and transonic-flow fan. A novel flow diagnostic method based on vorticity dynamics theory is utilized to analyze the reasons for the improvement in aerodynamic performance in the optimized transonic fan. In the established aerodynamic optimization method, use the blade profile camber line curvature and its leading edge metal angle as the optimization variables, which are optimized by modifying the coordinates of their control points and introducing a genetic algorithm. Finally, the vorticity dynamics parameters, such as the boundary vorticity flux (BVF), azimuthal vorticity and skin-friction lines are used to diagnose the key flow features in the optimized and baseline fan passage. The results indicate that, by controlling skillfully the blade camber line curvature in the optimization improves the aerodynamic performance of the fan stage, increasing the total pressure ratio by 1.90% while increasing the mass flow rate and adiabatic efficiency by 5.82% and 4.45%, respectively. The formulas from the vorticity dynamics diagnosis method indicate a close link between the aerodynamic performance and vorticity dynamic parameters for the axial fan/compressor passage flow, and that both azimuthal vorticity and boundary vorticity flux have significant influence on fan stage performance. Moreover, the boundary layer separation flow on the rotor blade surface is accompanied by a spike of entropy and static pressure, and their derivative/gradient also suffer drastic changes under the effect of shock waves. Detailed flow information can be obtained about the on-wall with high accuracy based on the vorticity dynamics diagnosis method, which provides researchers with a novel method for the turbomachinery aerodynamic design and analysis in the aero-engine engineering development field.
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Cárdenas-Ortiz, Laura, Nicholas J. Bayly, and Keith A. Hobson. "Fuel loads of Neotropical migrant songbirds on autumn passage through the Darién region of Colombia: Influence of migratory distance, route, ENSO, age and body size." Animal Migration 8, no. 1 (2021): 29–39. http://dx.doi.org/10.1515/ami-2020-0105.
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Abstract Available energy stores determine stopover length, migration speed and likely survival in migrating birds. We measured energy stores by estimating fuel load in 11 species of Neotropical migrant songbirds in the Darién of Colombia over five years. We evaluated 1) whether individuals flying further from breeding origin arrived with smaller fuel loads, 2) if the ENSO (El Niño-Southern Oscillation) cycle affected fuel load and 3) if species known to migrate mostly overwater arrived with less fuel relative to those migrating overland. Breeding origin, inferred from feather δ2H values, only had a significant positive effect on fuel load in Swainson’s Thrush (Catharus ustulatus). Veery (Catharus fuscescens) and Swainson’s thrush had higher and lower fuel loads, respectively, in El Niño years. Multi-species mixed-effects models revealed support for larger fuel loads in larger-bodied species and in species taking overwater routes, contrary to our prediction. Across species, we found no support for common effects of breeding origin or ENSO on fuel loads, in contrast to community-wide effects of migration route and body-size. In general, the variables considered here explained little of the variance in fuel loads, suggesting that inter-individual differences likely have a greater impact than broad-scale factors in our study system.
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Muscari, Roberto, Giulio Dubbioso, and Andrea Di Mascio. "Analysis of the flow field around a rudder in the wake of a simplified marine propeller." Journal of Fluid Mechanics 814 (February 9, 2017): 547–69. http://dx.doi.org/10.1017/jfm.2017.43.
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The vortex–body interaction problem, which characterizes the flow field of a rudder placed downstream of a single-blade marine rotor, is investigated by numerical simulations. The particular topology of the propeller wake, consisting of a helicoidal vortex detached from the blade tips (tip vortex) and a longitudinal, streamwise oriented vortex originating at the hub (hub vortex), embraces two representative mechanisms of vortex–body collisions: the tip vortices impact almost orthogonally to the mean plane, whereas the hub vortex travels in the mean plane of the wing (rudder), perpendicularly to its leading edge. The two vortices evolve independently only during the approaching and collision phases. The passage along the body is instead characterized by strong interaction with the boundary layer on the rudder and is followed by reconnection and merging in the middle and far wake. The features of the wake were investigated by the $\unicode[STIX]{x1D706}_{2}$-criterion (Jeong & Hussain, J. Fluid Mech., vol. 285, 1995, pp. 69–94) and typical flow variables (pressure, velocity and vorticity) of the instantaneous flow field; wall pressure spectra were analysed and related to the tip and hub vortices evolution, revealing a non-obvious behaviour of the loading on the rudder that can be related to undesired unsteady loads.
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Dugan, Liam, Daphne Ippolito, Arun Kirubarajan, Sherry Shi, and Chris Callison-Burch. "Real or Fake Text?: Investigating Human Ability to Detect Boundaries between Human-Written and Machine-Generated Text." Proceedings of the AAAI Conference on Artificial Intelligence 37, no. 11 (2023): 12763–71. http://dx.doi.org/10.1609/aaai.v37i11.26501.
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As text generated by large language models proliferates, it becomes vital to understand how humans engage with such text, and whether or not they are able to detect when the text they are reading did not originate with a human writer. Prior work on human detection of generated text focuses on the case where an entire passage is either human-written or machine-generated. In this paper, we study a more realistic setting where text begins as human-written and transitions to being generated by state-of-the-art neural language models. We show that, while annotators often struggle at this task, there is substantial variance in annotator skill and that given proper incentives, annotators can improve at this task over time. Furthermore, we conduct a detailed comparison study and analyze how a variety of variables (model size, decoding strategy, fine-tuning, prompt genre, etc.) affect human detection performance. Finally, we collect error annotations from our participants and use them to show that certain textual genres influence models to make different types of errors and that certain sentence-level features correlate highly with annotator selection. We release the RoFT dataset: a collection of over 21,000 human annotations paired with error classifications to encourage future work in human detection and evaluation of generated text.
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Zhan, Huixin, and Victor S. Sheng. "Privacy-Preserving Representation Learning for Text-Attributed Networks with Simplicial Complexes." Proceedings of the AAAI Conference on Artificial Intelligence 37, no. 13 (2023): 16143–44. http://dx.doi.org/10.1609/aaai.v37i13.26932.
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Although recent network representation learning (NRL) works in text-attributed networks demonstrated superior performance for various graph inference tasks, learning network representations could always raise privacy concerns when nodes represent people or human-related variables. Moreover, standard NRLs that leverage structural information from a graph proceed by first encoding pairwise relationships into learned representations and then analysing its properties. This approach is fundamentally misaligned with problems where the relationships involve multiple points, and topological structure must be encoded beyond pairwise interactions. Fortunately, the machinery of topological data analysis (TDA) and, in particular, simplicial neural networks (SNNs) offer a mathematically rigorous framework to evaluate not only higher-order interactions, but also global invariant features of the observed graph to systematically learn topological structures. It is critical to investigate if the representation outputs from SNNs are more vulnerable compared to regular representation outputs from graph neural networks (GNNs) via pairwise interactions. In my dissertation, I will first study learning the representations with text attributes for simplicial complexes (RT4SC) via SNNs. Then, I will conduct research on two potential attacks on the representation outputs from SNNs: (1) membership inference attack, which infers whether a certain node of a graph is inside the training data of the GNN model; and (2) graph reconstruction attacks, which infer the confidential edges of a text-attributed network. Finally, I will study a privacy-preserving deterministic differentially private alternating direction method of multiplier to learn secure representation outputs from SNNs that capture multi-scale relationships and facilitate the passage from local structure to global invariant features on text-attributed networks.
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Romero Olguín, D. S., and L. F. Guerrero Baca. "ADOBE VERNACULAR HOUSING TYPOLOGICAL ANALYSIS IN CALIMAYA DE DÍAZ GONZALEZ, STATE OF MEXICO." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIV-M-1-2020 (July 24, 2020): 1005–10. http://dx.doi.org/10.5194/isprs-archives-xliv-m-1-2020-1005-2020.
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Abstract. Climate, topography, hydrology, and all the factors of the natural environment affecting a population, as well as accessibility to materials and its ease of transport have constituted the variables determining the vernacular housing characteristics. In the territory which now covers Calimaya various cultural groups settled, making evident the syncretism of various building traditions. Since its formation the place was a site of passage, which communicated various goods transport, generating a peculiar urban physiognomy and cultural exchange, leading to the introduction of buildings, typical of this place. The town’s current situation is characterized by a rapid process of urbanization and social transformation, generating new needs of usage and habitability. This growth transforms the architecture of the place, replacing it with buildings with physiognomic features that do not correspond to the original context, causing loss of local construction techniques. Assuming that typology is a theoretical and creative activity allowing the definition and structuring of a system of conceptual relations, within certain limits, in order to determine the representative elements of vernacular architecture of the site, a typological analysis is being carried out to identify local materials and buildings systems, its characteristics, and spatial shape. Likewise, a constructive and architectural analysis, identifying traditional building techniques, which will favour the development of solutions facing the problem of conservation, maintenance and sustainability in the locality, is being carried out.
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Low, Daniel M., Vishwanatha Rao, Gregory Randolph, Phillip C. Song, and Satrajit S. Ghosh. "Identifying bias in models that detect vocal fold paralysis from audio recordings using explainable machine learning and clinician ratings." PLOS Digital Health 3, no. 5 (2024): e0000516. http://dx.doi.org/10.1371/journal.pdig.0000516.
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Detecting voice disorders from voice recordings could allow for frequent, remote, and low-cost screening before costly clinical visits and a more invasive laryngoscopy examination. Our goals were to detect unilateral vocal fold paralysis (UVFP) from voice recordings using machine learning, to identify which acoustic variables were important for prediction to increase trust, and to determine model performance relative to clinician performance. Patients with confirmed UVFP through endoscopic examination (N = 77) and controls with normal voices matched for age and sex (N = 77) were included. Voice samples were elicited by reading the Rainbow Passage and sustaining phonation of the vowel "a". Four machine learning models of differing complexity were used. SHapley Additive exPlanations (SHAP) was used to identify important features. The highest median bootstrapped ROC AUC score was 0.87 and beat clinician’s performance (range: 0.74–0.81) based on the recordings. Recording durations were different between UVFP recordings and controls due to how that data was originally processed when storing, which we can show can classify both groups. And counterintuitively, many UVFP recordings had higher intensity than controls, when UVFP patients tend to have weaker voices, revealing a dataset-specific bias which we mitigate in an additional analysis. We demonstrate that recording biases in audio duration and intensity created dataset-specific differences between patients and controls, which models used to improve classification. Furthermore, clinician’s ratings provide further evidence that patients were over-projecting their voices and being recorded at a higher amplitude signal than controls. Interestingly, after matching audio duration and removing variables associated with intensity in order to mitigate the biases, the models were able to achieve a similar high performance. We provide a set of recommendations to avoid bias when building and evaluating machine learning models for screening in laryngology.
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Latterini, Francesco, Rachele Venanzi, Walter Stefanoni, and Rodolfo Picchio. "Disturbance Caused by Animal Logging to Soil Physicochemical and Biological Features in Oak Coppices: A Case-Study in Central Italy." Forests 14, no. 3 (2023): 655. http://dx.doi.org/10.3390/f14030655.
Full textAbstract:
Firewood extraction by mule forwarding is still common in oak coppices in Central and Southern Italy. This is due to the scarce presence of aerial extraction systems such as cable yarders. Considering the importance of forest soil for all ecosystem services, the evaluation of the disturbance that a given extraction system has on the forest soil is a fundamental aspect in the framework of sustainable forest management. Therefore, this study was developed to assess the disturbance caused to the physicochemical and biological features of soil and to coppice after mule logging according to the standards of silvicultural treatment, as well as the recovery time needed after the logging intervention. Four cutting blocks located in Central Italy represented the study area, one cutting block represented the unharvested control, while the others were logged 3 years (CB-2019), 8 years (CB-2014) and 10 years (CB-2012) prior to the field surveys. In each harvested cutting block the soil was subdivided into disturbed soil (DIST—mule trails) and low disturbance soil (LD—area within the harvested cutting block not affected by mule passage). This experimental design assessed the disturbance caused by logging operations by mules (DIST soil) and the silvicultural treatment (LD soil) to soil physicochemical (bulk density, penetration resistance, shear resistance, and soil organic matter) and biological properties (soil microarthropod community evaluated with the QBS-ar index). The results revealed a significant disturbance in the mule trails for all the investigated variables. The disturbance was particularly strong for the QBS-ar index, with values which were lower than half of those of the control area. Furthermore, no recovery process was evident even after 10 years from the logging interventions. Instead, values of the various parameters became worse with time after harvesting. On the other hand, no marked disturbance was revealed in LD soil, except for a significant decrease in soil organic matter. Although this is a preliminary evaluation that needs to be confirmed with further study, this trial suggested that mule logging cannot be considered a fully low-impact approach to forest operations and that studies with a longer time span after harvesting are needed to assess the recovery process in the mule trails.
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Singla, Nirmish, Layton Woolford, Christina Stevens, et al. "Leveraging a robust patient-derived xenograft platform to characterize predictors for engraftment and oncologic outcomes in renal cell carcinoma patients." Journal of Clinical Oncology 37, no. 7_suppl (2019): 651. http://dx.doi.org/10.1200/jco.2019.37.7_suppl.651.
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651 Background: Patient-derived xenograft (PDX) models of renal cell carcinoma (RCC) preserve the biological features of patient tumors, providing a platform for biomarker identification and preclinical drug testing. We sought to identify predictors of successful tumor engraftment and evaluate the prognostic value of engraftment in patients with RCC using a robust murine PDX platform. Methods: 1,200 specimens derived from nephrectomy, thrombectomy, metastasectomy, or biopsy were orthotopically (renally) implanted into NOD/SCID mice between 2008-2018. Non-RCC pathology was excluded. Stable engraftment was defined by successful passage of tumor tissue at least twice with histologic confirmation. Clinicopathologic characteristics were stratified by engraftment status, and multivariate (MVA) logistic regression was used to identify predictors of engraftment. Kaplan-Meier and Cox regression analyses were used to assess the prognostic value of engraftment on patient overall (OS) and disease-free (DFS) survival. Results: 1,003 independent PDX lines derived from 770 RCC patients were included. 157 (15.6%) lines successfully engrafted and exhibited higher tumor grade, stage, size, and presence of sarcomatoid or rhabdoid components. Whole exome sequencing was performed on 230 PDX lines. On MVA, sarcomatoid (OR 5.71, p < 0.001), rhabdoid (OR 2.79, p = 0.046), and advanced stage (OR 1.72, p = 0.049) were significant predictors for engraftment, while high grade and metastatic tumor source were significant only on UVA. Engraftment was associated with poor OS (HR 2.11, p < 0.001) and DFS (HR 1.85, p = 0.020) in patients after controlling for sarcomatoid, rhabdoid, grade, stage, and age on MVA. Conclusions: Aggressive RCC biology correlates with successful engraftment in PDX models. Engraftment remains independently predictive of OS and DFS even after controlling for adverse pathologic features. Engraftment in mice may illuminate aspects of tumor biology not captured by clinicopathologic variables and provide insight into novel determinants of tumor aggressiveness and metastasis. Efforts are underway to elucidate genomic drivers of engraftment.
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Abhulimen, Victor, and Vitalis Obisike Ofuru. "Aetiopathogenesis of urethral stricture disease in a tertiary hospital in Southern Nigeria." International Surgery Journal 10, no. 1 (2022): 11. http://dx.doi.org/10.18203/2349-2902.isj20223586.
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Background: The urethra provides passage for urine in both sexes and additionally for ejaculation in males. Urethral stricture disease (USD), results in the narrowing of the urethra due to spongiofibrosis. Understanding the pathology of this disease is important to treatment. This study aims to evaluate the aetiology, pathology and pathogenesis of USD at the University of Port Harcourt Teaching Hospital.Methods: This was a 6-year retrospective study conducted on all patients with features of USD who presented to the University of Port Harcourt Teaching Hospital UPTH. Ethical approval was sought and obtained from the hospital’s ethical committee. Data were obtained from ward admission, theatre, and discharge records. The information gotten included the age of the patient, aetiologic agent, site of stricture, number of strictures, length of stricture and complications present at the presentation. The data retrieved was analysed and categorical data were presented in the form of frequencies and percentages using tables. Continuous variables were presented as means and standard deviation. Results were presented in tables and charts.Results: The mean age from this study was 44.1±16.7 years. The commonest site of USD was bulbar with 74 (67.27%) patients. The commonest cause of urethral stricture was iatrogenic (41 patients).Conclusions: Strictures are commonest amongst middle-aged men. The commonest site of urethral stricture disease is the bulbar region because of its unique anatomy. Iatrogenic strictures are the commonest cause of urethra stricture disease.
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Krasulia, Alla, and Vladyslav Kravchenko. "Translation and Localization Features of English Video Games (Based on the Subnautica Franchise)." Vìsnik Marìupolʹsʹkogo deržavnogo unìversitetu Serìâ Fìlologìâ 14, no. 25 (2021): 176–82. http://dx.doi.org/10.34079/2226-3055-2021-14-25-176-182.
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Video games are continuously growing in popularity with every year. As the video game market is growing, more games get localized into other languages including Ukrainian. There is still not enough research on translation aspects of video game localization although translation scholars and localization experts have created a solid theoretical framework for such studies. The article deals with the translation and localization features of English video games. It is important to differentiate between translation and localization. The former refers to the entire process of adapting digital products for new markets including technical, business and cultural issues. The latter is an inherent part of localization but it only involves linguistic issues. It was revealed that the main features of video game discourse are interactivity and multimodality, i.e. the application of multiple semiotic systems within one medium. They both influence the types of text in video games, thus being important aspects for localization. It is established that the main purpose of video game discourse is to engage the player. It was pointed out that in-game texts are the main assets for localization. They are divided into a user interface, narrative and descriptive passages and dialogues. Each of them serves a different communicative function. Based on the survival action-adventure video game series Subnautica, the most common translation difficulties were established. One of them is the translation of non-equivalent lexical units that are mostly presented by names of fictional animals, plants and technology. The analysis of chosen translation strategies showed that the most efficient way of dealing is realizing the motivation behind their naming and creating an equivalent that would not contradict their depiction in the game. It was stated that pragmatic translation difficulties concern creating the same communicative effect as in the original. To deal with them, the translation should have a deep understanding of video game mechanics. Stylistic translation difficulties in video games are similar to those in fiction. They concern the rendition of different registers and stylistic devices in the target language. Technical translation difficulties were described as a special type inherent to video game localization. They might be caused by character limits and variables. To solve them, the translator often resorts to compression, omission and the complete restructuring of a sentence. Thus, video game localization is a complex type of translation that shares similar features with software localization, literary and audiovisual translation. Video game localizers often employ creative transformation to deal with technological limitations. Translators in this field should be aware of all types of in-game texts and their function to correctly render them in the target language.
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Crosta, G. B., and F. Agliardi. "A methodology for physically based rockfall hazard assessment." Natural Hazards and Earth System Sciences 3, no. 5 (2003): 407–22. http://dx.doi.org/10.5194/nhess-3-407-2003.
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Abstract. Rockfall hazard assessment is not simple to achieve in practice and sound, physically based assessment methodologies are still missing. The mobility of rockfalls implies a more difficult hazard definition with respect to other slope instabilities with minimal runout. Rockfall hazard assessment involves complex definitions for "occurrence probability" and "intensity". This paper is an attempt to evaluate rockfall hazard using the results of 3-D numerical modelling on a topography described by a DEM. Maps portraying the maximum frequency of passages, velocity and height of blocks at each model cell, are easily combined in a GIS in order to produce physically based rockfall hazard maps. Different methods are suggested and discussed for rockfall hazard mapping at a regional and local scale both along linear features or within exposed areas. An objective approach based on three-dimensional matrixes providing both a positional "Rockfall Hazard Index" and a "Rockfall Hazard Vector" is presented. The opportunity of combining different parameters in the 3-D matrixes has been evaluated to better express the relative increase in hazard. Furthermore, the sensitivity of the hazard index with respect to the included variables and their combinations is preliminarily discussed in order to constrain as objective as possible assessment criteria.
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Lee, Taesic, Sangwon Hwang, Dongmin Seo, et al. "Comparative Analysis of Biological Signatures between Freshly Preserved and Cryo-Preserved Bone Marrow Mesenchymal Stem Cells." Cells 12, no. 19 (2023): 2355. http://dx.doi.org/10.3390/cells12192355.
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Mesenchymal stem cells (MSCs) can differentiate into multiple connective tissue lineages, including osteoblasts, chondrocytes, and adipocytes. MSCs secrete paracrine molecules that are associated with immunomodulation, anti-fibrotic effects, and angiogenesis. Due to their orchestrative potential, MSCs have been therapeutically applied for several diseases. An important aspect of this process is the delivery of high-quality MSCs to patients at the right time, and cryo-biology and cryo-preservation facilitate the advancement of the logistics thereof. This study aimed to compare the biological signatures between freshly preserved and cryo-preserved MSCs by using big data sourced from the Pharmicell database. From 2011 to 2022, data on approximately 2300 stem cell manufacturing cases were collected. The dataset included approximately 60 variables, including viability, population doubling time (PDT), immunophenotype, and soluble paracrine molecules. In the dataset, 671 cases with no missing data were able to receive approval from an Institutional Review Board and were analyzed. Among the 60 features included in the final dataset, 20 were selected by experts and abstracted into two features by using a principal component analysis. Circular clustering did not introduce any differences between the two MSC preservation methods. This pattern was also observed when using viability, cluster of differentiation (CD) markers, and paracrine molecular indices as inputs for unsupervised analysis. The individual average PDT and cell viability at most passages did not differ according to the preservation method. Most immunophenotypes (except for the CD14 marker) and paracrine molecules did not exhibit different mean levels or concentrations between the frozen and unfrozen MSC groups. Collectively, the biochemical signatures of the cryo-preserved and unfrozen bone marrow MSCs were comparable.
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Bochsler, Philip N., David O. Slauson, Suzanne K. Chandler, and M. Mitsu Suyemoto. "Isolation and characterization of equine microvascular endothelial cells in vitro." American Journal of Veterinary Research 50, no. 10 (1989): 1800–1805. https://doi.org/10.2460/ajvr.1989.50.10.1800.
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SUMMARY The use of cultured tissue has not yet become widespread in research involving equine disease, and this may be attributable in part to the scarcity of published reports concerning tissue culture methods for this species. We report here the isolation of equine microvascular endothelium (emve) from fresh omental tissue of horses and ponies. Fresh donor tissue was minced, subjected to collagenase digestion, and filtered. Cells were layered on 5% bovine serum albumin for gravity sedimentation, the bottom layer was collected, and the cells were plated onto fibronectin-coated flasks. Medium consisted of Dulbecco modified Eagle medium with 10% whole fetal bovine serum (wfbs) and 20 μg of endothelial cell growth supplement/ml. The emve grew readily in culture, had the cobblestone morphologic feature at confluence, stained positively for factor VIII-related antigen, and metabolized acetylated low-density lipoprotein. Fibroblast and smooth muscle cell contamination was minimal in primary cell cultures, which were successfully passed and maintained in culture for 3 to 5 serial passages, using various media and substrates. Preliminary studies were undertaken to determine optimal growth conditions with a range of variables: serum concentration, extracellular matrix components, and growth factors, Optimal conditions were achieved with a minimum of 10% wfbs, and with either fibronectin or laminin as extracellular matrix substrates. The emve grew adequately in Dulbecco modified Eagle medium plus 10% wfbs, and the added growth factors or serum supplements did not appear necessary for growth of emve.
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Singla, Nirmish, Layton Woolford, Christina Stevens, et al. "Leveraging a robust patient-derived xenograft platform to characterize predictors for engraftment and oncologic outcomes in renal cell carcinoma patients." Journal of Clinical Oncology 37, no. 15_suppl (2019): e16100-e16100. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.e16100.
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e16100 Background: Patient-derived xenograft (PDX) models of renal cell carcinoma (RCC) preserve the biological features of patient tumors, providing a platform for biomarker identification and preclinical drug testing. We sought to identify predictors of successful tumor engraftment and evaluate the prognostic value of engraftment in patients with RCC using a robust murine PDX platform. Methods: 1,200 specimens derived from nephrectomy, thrombectomy, metastasectomy, or biopsy were orthotopically (renally) implanted into NOD/SCID mice between 2008-2018. Non-RCC pathology was excluded. Stable engraftment was defined by successful passage of tumor tissue at least twice with histologic confirmation. Clinicopathologic characteristics were stratified by engraftment status, and multivariate (MVA) logistic regression was used to identify predictors of engraftment. Kaplan-Meier and Cox regression analyses were used to assess the prognostic value of engraftment on patient overall (OS) and disease-free (DFS) survival. Results: 1,003 independent PDX lines derived from 770 RCC patients were included. 157 (15.6%) lines successfully engrafted and exhibited higher tumor grade, stage, size, and presence of sarcomatoid or rhabdoid components. 79.3% of all tumors were of clear cell histology, and histologic distribution did not vary by engraftment status. We have completed whole exome sequencing and RNAseq on 197 and 213 PDX lines, respectively, and downstream analyses will be reported. On MVA, sarcomatoid (OR 5.71, p < 0.001), rhabdoid (OR 2.79, p = 0.046), and advanced stage (OR 1.72, p = 0.049) were significant predictors for engraftment, while high grade and metastatic tumor source were significant only on UVA. Engraftment was associated with poor OS (HR 2.11, p < 0.001) and DFS (HR 1.85, p = 0.020) in patients after controlling for sarcomatoid, rhabdoid, grade, stage, and age on MVA. Conclusions: Aggressive RCC biology correlates with successful engraftment in PDX models. Engraftment remains independently predictive of OS and DFS even after controlling for adverse pathologic features. Engraftment in mice may illuminate aspects of tumor biology not captured by clinicopathologic variables and provide insight into novel determinants of tumor aggressiveness and metastasis.
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Taylor, Sammi, Christopher Dromey, Shawn L. Nissen, Kristine Tanner, Dennis Eggett, and Kim Corbin-Lewis. "Age-Related Changes in Speech and Voice: Spectral and Cepstral Measures." Journal of Speech, Language, and Hearing Research 63, no. 3 (2020): 647–60. http://dx.doi.org/10.1044/2019_jslhr-19-00028.
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Purpose This study examined differences in selected acoustic measures of speech and voice according to age and sex and across families. Method Participants included 169 individuals, 79 men and 90 women, from 18 families, ranging in age from 17 to 87 years. Participants reported no history of articulation disorders, stroke or active neurologic disease, or severe-to-profound hearing loss. They read aloud two passages to facilitate examination of the following speech and voice acoustic parameters: fricative spectral moments (center of gravity, standard deviation, skewness, and kurtosis), the proportion of time spent speaking, mean speaking fundamental frequency, semitone standard deviation (STSD), and cepstral peak prominence smoothed. Results The results indicated a significant age effect for fricative spectral center of gravity, spectral skewness, and speaking STSD. There was a significant sex effect for spectral center of gravity, spectral kurtosis, and mean fundamental frequency. Familial relationship was significant for spectral skewness, STSD, and cepstral peak prominence smoothed. Conclusions These findings revealed that certain speech and voice features change with age and some change differently for men and women. Additionally, speakers from the same family units may demonstrate similar patterns for prosody, voicing, and articulatory behavior. The results also demonstrated normal differences in speech and voice variation across age, sex, and family unit. Understanding patterns and differences across these demographic variables in healthy speakers is important to distinguishing more confidently between normal and disordered speech and voice patterns clinically.
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Flanagan, Paul X., Jeffrey B. Basara, Jason C. Furtado, and Xiangming Xiao. "Primary Atmospheric Drivers of Pluvial Years in the United States Great Plains." Journal of Hydrometeorology 19, no. 4 (2018): 643–58. http://dx.doi.org/10.1175/jhm-d-17-0148.1.
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Abstract Precipitation variability has increased in recent decades across the Great Plains (GP) of the United States. Drought and its associated drivers have been studied in the GP region; however, periods of excessive precipitation (pluvials) at seasonal to interannual scales have received less attention. This study narrows this knowledge gap with the overall goal of understanding GP precipitation variability during pluvial periods. Through composites of relevant atmospheric variables from the ECMWF twentieth-century reanalysis (ERA-20C), key differences between southern Great Plains (SGP) and northern Great Plains (NGP) pluvial periods are highlighted. The SGP pluvial pattern shows an area of negative height anomalies over the southwestern United States with wind anomalies consistent with frequent synoptic wave passages along a southward-shifted North Pacific jet. The NGP pattern during pluvial periods, by contrast, depicts anomalously low heights in the northwestern United States and an anomalously extended Pacific jet. Analysis of daily heavy precipitation events reveals the key drivers for these pluvial events, namely, an east–west height gradient and associated stronger poleward moisture fluxes. Therefore, the results show that pluvial years over the GP are likely driven by synoptic-scale processes rather than by anomalous seasonal precipitation driven by longer time-scale features. Overall, the results present a possible pathway to predicting the occurrence of pluvial years over the GP and understanding the causes of GP precipitation variability, potentially mitigating the threats of water scarcity and excesses for the public and agricultural sectors.
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Rahmawati, Aulia, Ida Rosmalina, and Hesti Wahyuni Anggraini. "Prosodic reading and reading comprehension in university." EduLite: Journal of English Education, Literature and Culture 5, no. 1 (2020): 89. http://dx.doi.org/10.30659/e.5.1.89-108.
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This study was aimed at investigating the students’ English reading comprehension on the basis of the importance of prosodic reading in university level by first, measuring the levels of reading prosody and reading comprehension, characterizing the acoustic characteristics produced by the students, and at last associating the first variable to the second variable. Prosodic reading levels were measured by using Multidimensional Fluency Scale, containing four dimensions. To explore the six types of syntactically complex structures produced by the students orally, this study conducted a descriptive analysis, only focused on some features. The findings showed that the students experienced moderate level of reading prosody and reading comprehension. Also, it could be reported that a significant correlation was found between the two variables. The study reported that prosodic reading contributed to reading comprehension with r-obtained .538. A thorough analysis explained that some other related predictors influenced students’ comprehension, like difficulties in recognizing the vocabulary, lack of knowledge to review the four types of sentences, and the length of the passage. Among four dimensions, only pace and expression & volume did contribute to reading comprehension much. Different pause structures produced by the students and the native speakers were clearly identified. This was shown as many students had a long pause and sound hesitate due to their inability to decode the words. Moreover, most of them could not comprehend the sentence structure of the text, when to pause, which words were needed to be stressed, and the intonation used. As a result, they read in a two-three phrases and declined to notice where the endings of sentences and clauses were definitely stated. These results confirmed that pause structure commits as a pivotal factor in determining students’ reading comprehension.
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Cappiello, Alessandro, and Raffaele Tuccillo. "Design and CFD Analysis of a Radial-Inflow Turbine for Small Scale ORC Applications." E3S Web of Conferences 197 (2020): 11005. http://dx.doi.org/10.1051/e3sconf/202019711005.
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In recent years, Organic Rankine Cycle (ORC) technology has received growing interests, thanks to its high flexibility and to the capability to exploit energy sources at temperature levels difficult to be approached with conventional power cycles. These features allow exploiting renewable and renewable-equivalent energy sources, by either improving the energy conversion efficiency of existing plants or using waste heat from industrial process. As far as the expander is concerned, a high potential solution is represented by turbo-expanders, which allow reduction of plant clutter and complexity, so enhancing the potential impact on the diffusion of small power ORC-based plants. The present work concerns the design of a RadialInflow Turbine for a bottoming Organic Rankine Cycle in the tens of kW scale. Design boundary conditions are retrieved by a zero-dimensional model of a solar-assisted micro gas turbine in cogenerating mode. The design process is started by means of an in-house mean-line design code accounting for real gas properties. The code is used to carry out parametric analyses to investigate the design space for several working fluids encompassing different classes, namely refrigerants and siloxanes. The program is used to assess the effect of design variables and working fluid on the turbine performance and turbine design characteristics. Subsequently, the most promising design candidates are selected and three-dimensional first guess stator and rotor geometries are built on these preliminary designs. Stationary and rotating passages are then meshed and analyzed by means of RANS CFD based solution of the stator – rotor interaction.
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Iovino, Doroteaciro, Pier Giuseppe Fogli, and Simona Masina. "Evaluation of the CMCC global eddying ocean model for the Ocean Model Intercomparison Project (OMIP2)." Geoscientific Model Development 16, no. 21 (2023): 6127–59. http://dx.doi.org/10.5194/gmd-16-6127-2023.
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Abstract. This paper describes the global eddying ocean–sea ice simulation produced at the Euro-Mediterranean Center on Climate Change (CMCC) obtained following the experimental design of the Ocean Model Intercomparison Project phase 2 (OMIP2). The eddy-rich model (GLOB16) is based on the NEMOv3.6 framework, with a global horizontal resolution of 1/16∘ and 98 vertical levels and was originally designed for an operational short-term ocean forecasting system. Here, it is driven by one multi-decadal cycle of the prescribed JRA55-do atmospheric reanalysis and runoff dataset in order to perform a long-term benchmarking experiment. To assess the accuracy of simulated 3D ocean fields and highlight the relative benefits of resolving mesoscale processes, the GLOB16 performances are evaluated via a selection of key climate metrics against observational datasets and two other NEMO configurations at lower resolutions: an eddy-permitting resolution (ORCA025) and a non-eddying resolution (ORCA1) designed to form the ocean–sea ice component of the fully coupled CMCC climate model. The well-known biases in the low-resolution simulations are significantly improved in the high-resolution model. The evolution and spatial pattern of large-scale features (such as sea surface temperature biases and winter mixed-layer structure) in GLOB16 are generally better reproduced, and the large-scale circulation is remarkably improved compared to the low-resolution oceans. We find that eddying resolution is an advantage in resolving the structure of western boundary currents, the overturning cells, and flow through key passages. GLOB16 might be an appropriate tool for ocean climate modeling efforts, even though the benefit of eddying resolution does not provide unambiguous advances for all ocean variables in all regions.