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311.
Aidan O. Donnell 《The Law teacher》2013,47(3):231-236
ABSTRACTThe theory of threshold concepts has become a popular way to describe the difficulties students face when trying to grasp fundamental ideas in a discipline. In law authors have suggested a range of concepts as thresholds. However these suggestions conflict with each other, and have not emphasised the way in which students repeatedly encounter such thresholds. Using variation theory and the concept of knowledge capability this article suggests that the Threshold Capability Integrated Theoretical Framework may be a way to resolve those differences and to highlight the ongoing nature of liminality in becoming a professional. Students may grasp initial threshold concepts early in a degree or subject, develop the ability to manipulate and use them in a variety of settings towards the end of the degree, and develop a lifelong professional ability to use them in diverse settings after graduation. Law students, lawyers and indeed law teachers may be best seen as in a constant state of learning. The uncertainty that goes with that learning is to be embraced, and encouraged as part of the way we teach law. 相似文献
312.
Arnt O. Hopland 《Public Choice》2014,161(1-2):233-255
This paper studies the effect on vote shares and reelection probability for the incumbent’s party from a signal indicating poor fiscal performance. In Norway, local governments with persistent deficits are placed in the Register for State Review and Approval of Financial Obligations (Robek). In addition to increased central government monitoring, placement in Robek triggers a great deal of attention in the local media. It is thus expected to raise voter awareness of the fiscal stance of the local government. The results indicate that voters value the information embedded in this signal, and take it into account when casting their votes. Both the share of votes for the incumbent’s party and the probability that the incumbent party stays in office is significantly reduced as a consequence of the local government being included in the register. The vote share for the incumbent is reduced by about three percentage points, while the reelection probability is reduced by about 0.12. 相似文献
313.
Katharine O. Strunk Andrew McEachin Theresa N. Westover 《Journal of policy analysis and management》2014,33(3):719-751
The theory of action upon which high‐stakes accountability policies are based calls for systemic reforms in educational systems that will emerge by pairing incentives for improvement with extensive and targeted technical assistance (TA) to build the capacity of low‐performing schools and districts. To this end, a little discussed and often overlooked aspect of the No Child Left Behind Act (NCLB) mandated that, in addition to sanctions, states were required to provide TA to build the capacity of struggling schools and Local Education Agencies (LEAs, or districts) to help them improve student achievement. Although every state in the country provides some form of TA to its lowest performing districts, we know little about the content of these programs or about their efficacy in improving student performance. In this paper, we use both quantitative and qualitative analyses to explore the actions taken by TA providers in one state—California—and examine whether the TA and support tied to California's NCLB sanctions succeeds in improving student achievement. Like many other states, California requires that districts labeled as persistently failing under NCLB (in Program Improvement year 3, PI3) work with external experts to help them build the capacity to make reforms that will improve student achievement. California's lowest performing PI3 districts are given substantial amounts of funding and are required to contract with state‐approved District Assistance and Intervention Teams (DAITs), whereas the remaining PI3 districts receive less funding and are asked to access less intensive TA from non‐DAIT providers. We use a five‐year panel difference‐in‐difference design to estimate the impacts of DAITs on student performance on the math and English language arts (ELA) standardized tests relative to non‐DAIT TA during the two years of the program intervention. We find that students in districts with DAITs perform significantly better on math California Standards Tests (CSTs) averaged over both treatment years and in each of the first and second years. We do not find evidence that students in districts with DAITs perform higher on ELA CSTs over the combined two years of treatment, although we find suggestive evidence that ELA performance increases in the second year of treatment relative to students in districts with non‐DAIT TA. Ordinary least squares (OLS) regressions that explore the association between specific activities fostered by DAITs and changes in districts’ gains in achievement over the two years of treatment show that DAIT districts that report increasing their focus on using data to guide instruction, shifting district culture to generate and maintain high expectations of students and staff, and increasing within‐district accountability for student performance, have higher math achievement gains over the course of the DAIT treatment. In addition, DAIT districts that increase their focus on ELA instruction and shift district culture to one of high expectations have higher ELA achievement gains than do DAIT districts that do not have a similar focus. © 2012 by the Association for Public Policy Analysis and Management. 相似文献
314.
315.
Forensic determination of hair deposition time in crime scenes using electron paramagnetic resonance
Nikhita Shankar MS André O. Guimarães PhD Eleonora Napoli PhD Cecilia Giulivi MS PhD 《Journal of forensic sciences》2021,66(1):72-82
Several types of biological samples, including hair strands, are found at crime scenes. Apart from the identification of the value and the contributor of the probative evidence, it is important to prove that the time of shedding of hair belonging to a suspect or victim matches the crime window. To this end, to estimate the ex vivo aging of hair, we evaluated time‐dependent changes in melanin‐derived free radicals in blond, brown, and black hairs by using electron paramagnetic resonance spectroscopy (EPR). Hair strands aged under controlled conditions (humidity 40%, temperature 20–22°C, indirect light, with 12/12 hour of light/darkness cycles) showed a time‐dependent decay of melanin‐derived radicals. The half‐life of eumelanin‐derived radicals in hair under our experimental settings was estimated at 22 ± 2 days whereas that of pheomelanin was about 2 days suggesting better stabilization of unpaired electrons by eumelanin. Taken together, this study provides a reference for future forensic studies on determination of degradation of shed hair in a crime scene by following eumelanin radicals by utilizing the non‐invasive, non‐destructive, and highly specific EPR technique. 相似文献
316.
Coral Luce M.S. Shawn Montpetit M.S. David Gangitano Ph.D. Patrick O’Donnell Ph.D. 《Journal of forensic sciences》2009,54(5):1046-1054
Abstract: The AmpF?STR® MiniFilerTM PCR Amplification Kit is designed to genotype degraded and/or inhibited DNA samples when the AmpF?STR® IdentifilerTM PCR Amplification Kit is incapable of generating a complete genetic profile. Validation experiments, following the SWGDAM guidelines, were designed to evaluate the performance of MiniFiler. Data obtained demonstrated that MiniFiler, when used in conjunction with Identifiler, provided an increased ability to obtain genetic profiles from challenged samples. The optimum template range was found to be between 0.2 and 0.6 ng, with 0.3 ng yielding the best results. Full concordance was achieved between the MiniFiler kit and Identifiler kit except in a single case of a null allele at locus D21S11. Numerous instances of severe heterozygous peak imbalance (<50%) were observed in single source samples amplified within the optimum range of input DNA suggesting that caution be taken when attempting to deduce component genotypes in a mixture. 相似文献
317.
J.E.L. VanDerNagel K.P. Tuts T. Hoekstra E.O. Noorthoorn 《International journal of law and psychiatry》2009,32(6):408-412
Knowledge of how nurses experience the process of secluding a patient can be useful in improving the quality of patient care and in the prevention of work related stress in nurses. This study describes personal experiences of nurses throughout the seclusion process. The emotions which came to surface in semi-structured interviews with 8 nurses were categorized in three main themes (Tension, Trust and Power) and a stress response curve was identified in the seclusion process, with specific feelings in each phase. Feelings denied in former studies such as feeling superior, anger and disgust were found in the interviews in this study. 相似文献
318.
Joseph P. Daly David R. Williams Stephen J. O’Connor Richard W. Pouder 《Social Justice Research》2009,22(4):335-350
There is a controversy in the justice literature as to whether interpersonal aspects of justice are best represented as one
construct (interactional justice) or two (interpersonal justice and informational justice). Using confirmatory factor analysis,
we tested competing models of these constructs on a sample of healthcare consumers (n = 1919) with respect to their justice judgments of primary care physicians. We found that the single factor model (interactional
justice) represented a better fit to the data. Our results do not necessarily contradict those of prior studies that have
found a better fit for a bi-dimensional model in organizational settings, however. Instead, we are suggesting a contingency
approach: the results may be due in part to the halo effect, which may manifest itself where consumers are unfamiliar with
the service provider and with the complexities of that person’s role. 相似文献
319.
E. Acar O. Bulbul G. Rayimoglu M.S. Shahzad D. Argac H. Altuncul G. Filoglu 《Forensic Science International: Genetics Supplement Series》2009,2(1):47-48
The use of ChrX-STRs is enormous in forensic case as these have proven to be powerful tools, mainly in deficiency paternity cases when the disputed child is female, and also some special cases involving blood relatives, incest cases, fetal typing in abortion material. The Mentype® Argus X-8 kit is a commercial multiplex system which contains Amelogenin for gender determination as well as gonosomal STR markers (DXS8378, HPRTB, DXS7423, DXS7132, DXS10134, DXS10074, DXS10101 and DXS10135). Validation studies were being performed on blood obtained from the volunteers in Turkish population. In this study, some parameters were taken under consideration for validation like DNA extraction using different protocols, quantitated by using commercially available Invitrogen Qubit Fluorometer, reaction volume validation of Master Mix and the analysis of female/male, female/female and male/male mixtures were performed. The conditions were optimized and validated using GenAmp 9700 and reducing reaction volume from 25 μl to 12.5 μl and 6.5 μl. After reducing the total volume of the reaction, the results were same and there was no effect on peak height and quality when analyzed on ABI 310 genetic analyzer. 2 paternity cases were also performed which gave the same power of discrimination as has been mentioned in Mentype® Argus X-8 kit. 相似文献
320.