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131.
Sowjanya B Sreenivasulu U Naidu JN Sivaranjani N 《Indian journal of clinical biochemistry : IJCB》2011,26(2):214-216
End stage renal disease (ESRD) represents a clinical condition in which there is an irreversible loss of endogenous renal
function. Both structural and functional abnormalities of the kidney are associated with increased morbidity, mortality. Bardet–Biedel
syndrome (BBS) is one of the rare genetic disorders with prevalence of 1 in 1, 40,000–1 in 1,60,000 worldwide. ESRD in BBS
patients is the final stage of the disease, increasing mortality in youth. 相似文献
132.
Unusual differential erosion related to the presence of endolithic microorganisms (Martvili,Georgia)
《Journal of Cultural Heritage》2014,15(5):538-545
The presence of a diffuse biodeterioration phenomena can be observed across large areas of the outer surface of the limestone walls of the Church of the Virgin in Martvili. A differential erosion phenomenon was detected, suggesting a possible association with biological colonization. The erosion phenomenon is characterized by a circular discoloration leading progressively to the detachment of flakes of limestone at its center. Since the aforementioned process has not been described in the literature until now, the present study was focused on the interpretation of its origin and evolution. Three sides of the Church are affected by a variety of occurrences of circular differential erosion which display different stages of the process, whereas the western side is affected by epilithic growths across its entire surface. Surveys of the petrographic, mineralogical and physical features of the stone were made, and parameters such as density and porosity were recorded. Samples were analyzed by optical microscopy and SEM analysis in order to detected the presence of microorganisms whose species were then identified by means of morphological and molecular examinations. The study of cross-sections stained using the PAS method has confirmed the causal connection between microorganisms and the deterioration phenomena, providing information about their spread of penetration into the substrate and their substantial potential for causing damage. Dryness appears to be the main ecological condition favoring endolithic rather than epilithic growth. The most common isolated microorganisms were cyanobacteria (Chroococcales) and, to a lesser extent, meristematic fungi. The characteristics of the stone, and especially some endogenous discontinuities related to the accumulation of sedimentary layers and to the action of stone carving tools, might explain why the same differential erosion phenomenon occurs in specific areas of the block stones. The development of the differential erosion phenomenon shows a variety of stages of biological colonization. The progressive evolution of the deterioration process has been observed in detail: (a) firstly, white circular discolorations appear on the stone, which darken over time eventually becoming almost black; (b) circular perforations appear around the perimeter; (c) and finally a flake detaches from the center, leaving a deep depression in the stone. 相似文献
133.
Recent research found a substantial effect of digital device type on a computerized, standardized assessment of learning. Findings were consistent across grade and content domain. To investigate the source of these differences, the current research probed whether measurement differences or, equivalently, test bias due to device type could explain achievement or proficiency differences. We used 2018–2019 results on the Indiana Learning Evaluation Assessment Readiness Network (ILEARN). The data are census-based and cover grades 3 and 8 in the content domains of mathematics and English language arts (ELA). For our analysis, we use the root mean-squared deviation (RMSD) for detecting measurement differences across students that took ILEARN on different digital devices. Our findings suggest that few, if any, achievement differences that depend on the type of digital device can be explained by test bias. We discuss our findings in the context of multiple-group versus multiple indicator, multiple cause measurement models. Our findings suggest that digital device operates directly on the construct (math or ELA) rather than on the indicators that measure the construct. Finally, we conclude that a competing hypothesis – that differences are due to a digital device familiarity effect – remains plausible. 相似文献
134.
135.
赵祥洪 《宁德师专学报(自然科学版)》2009,21(1):12-15
微分方程是反映有关的未知变量关于时间的导数和关于空间变量的导数之间制约关系的等式。许多领域中的数学模型都可以用微分方程来描述和求解,就微分方程的求解及其在生产中的应用略作探讨. 相似文献
136.
讨论了一类三阶非线性脉冲时滞微分方程解的振动性与渐进性,解决了非振动解与其导数的符号关系,所给出的充分条件改进了一些已知结果,并且比相关文献中的条件要简洁且易验证. 相似文献
137.
我们考虑如下常微分方程解的存在性问题:dxdt=f(x,x(t))(1,1)x(0)=ξ(1,2)在文章中,一定的假设条件下,分别应用shauder不动点定理与Banach不动点定理,证明它的解的存在性,这说明对于微分方程若假设条件不同所采取方法也不一样。 相似文献
138.
The development of unbiased tests is crucial in the arena of language testing in order to ensure validity. To date, studies of bias in language testing have mainly focused on factors such as gender, native language, or academic background, inter alia. However, bias may also result from psychological factors. Therefore, the present study investigates the role of English as a Foreign Language (EFL) test takers’ emotioncy, defined as the emotions evoked by senses that one holds for an entity, in their test performance. Specifically, this study aimed to examine emotioncy for the form as well as the meaning of 20 words to find out whether it can lead to differential functioning of the items on a vocabulary test. To this end, two emotioncy scales and a vocabulary test were designed. Then, based on the data collected from 235EFL students, the participants were bisected into the Low-Group and the High-Group, once based on their emotioncy scores for each word form and then based on their emotioncy scores for each word meaning. Subsequently, Rasch model-based Differential Item Functioning (DIF) analysis was performed across the two groups. The results showed that the vocabulary test items functioned differentially across the two groups in both form and meaning classifications, favoring the High-Group. Therefore, the study provides evidence for emotioncy as a psychological source of test bias and discusses implications for language testing stakeholders. 相似文献
139.
Over the past 20 years, jurisdictions across the United States have implemented differential response (DR), which provides child protective services with the flexibility to tailor their response to reports of child abuse or neglect based on the level of risk. Given the widespread adoption of DR, there has been an increasing demand from policymakers, practitioners, and community stakeholders to build the evidence base for this innovative child welfare approach. This study was designed to answer the big questions regarding the effect of differential response on child welfare outcomes and costs using a randomized controlled trial in five Colorado counties. Specifically, the study examined the safety outcomes and costs of families who were randomly assigned to either a family assessment response (FAR) or an investigation response (IR). According to the regression results, there were no differences between the tracks on measures of system re-involvement. However, survival analysis findings indicate that FAR families were 18% less likely, over time, to have a high risk assessment after their initial accepted referral than were IR families. The cost study revealed no differences between the tracks on initial costs for caseworker contacts, services, and out-of-home placements. However, the results suggest that follow-up costs for IR cases were significantly higher (p < 0.001) than for FAR cases. The authors discuss policy and practice implications for jurisdictions considering DR. 相似文献
140.
AbstractWe present adaptable activities for models of drug movement in the human body – pharmacokinetics – that motivate the learning of ordinary differential equations with an interdisciplinary topic. Specifically, we model aspirin, caffeine, and digoxin. We discuss the pedagogy of guiding students to understand, develop, and analyze models, progressing in complexity to a system of differential equations. We investigate the effects of parameter values that distinguish various health levels, and dosing that may have toxic effects. Our assignments include modeling in a student-centered, active, and increasingly inquiry-oriented setting through which the mathematics and biology inform and reinforce each other. We include supplemental information regarding inquiry methods, student learning outcomes, a student’s commentary about our activities, and support through mathematical communities such as POGIL and SIMIODE. 相似文献