904 resultados para 1472
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【目的】验证饱和链烷技术测定家畜食性和食量的精确性,确定绵羊粪便中链烷的回收率。【方法】于2004年秋季在中国科学院内蒙古草原生态系统定位研究站用不同放牧演替阶段的优势植物羊草(Lcymus chincnsis)、糙隐子草(Cleistogenes squarrosa)和冷蒿(Artemisia frigide)按一定比例混合组成日粮,饲喂9只2岁羯羊,每只羊投喂一粒QSM胶囊,试验期内每天记录绵羊实际牧草采食量、采食成分和排粪量,利用气相色谱分析牧草和粪样的链烷含量,应用链烷技术测定绵羊的排粪量、不同牧草呆食比例和总干物质采食量,并与实际值进行比较。【结果】3种牧草链烷模式存在种间差异;绵羊粪便中链烷的回收率随链烷长度的增加而线性增加;绵羊排粪量测定值与实际值存在极显著的正相关(P〈0.01,r=0.9994);绵羊采食羊草、糙隐子草和冷蒿比例的测定值与实际值存在极显著(P〈0.01)正相关,相关系数分别为0.9913、0.9864和0.9999;绵羊干物质采食量用C33:C32和C31:C31比值测定的值分别比实际值低4%(±1.3%)和7%(±1.3%),但差异不显著(P〉0.05)。【结论】饱和链烷技术可以精确测定典型草原绵羊的排粪量、食物组成和采食量。
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本发明涉及一种降压消脂保健组合物,该组合物是由油菜花粉、决明子浸膏粉、山楂浸膏粉、黄芪浸膏粉、红花浸膏粉、山药浸膏粉制成,本发明具有调节血压,降低血脂,延缓高血压进展以及合并高脂血症,增强机体免疫力功能的作用,可达到预防和辅助治疗高血压症以及合并高脂血症的目的。
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The velocity field is important to investigate the motion and strain parameters of the block. It is also important to investigate the deformation of the fault, for example, the accumulation of strain and stress, at the boundary of the block. The dislocation model is a classic method to simulate the velocity field. In dislocation model, the aseismic crustal deformation is regarded as the sum of the rigid block motion and the effect of the locked fault. We modify the dislocation model in two aspects. Firstly, the block motion is assumed to be the sum of rotation and linear strain rather than the rigid motion. Secondly, the elastic layered-earth model rather than the homogenous half-space model is applied to calculate the effect of the locked part. The 1990~1995 annually Global Position System (GPS) velocity data of the Taiwan area are used in our dislocation model. The misfit of our modified model is smaller than that of the origin model clearly. Our simulation shows, in eastern Coastal Range, the velocity decreases northward rapidly from Chimei Fault, which may result from the high crustal compressive rate of about 30 mm•a-1 at Chimei Fault. The lock of fault in southern part is stronger than that in northern part generally. In western Taiwan, the most strongly locked faults appear in the southern Coastal Plain where many disaster earthquakes occur frequently. The calculated strain and rotation rates consist with previous results in most areas. The strain rate field reveals the nearly NW-SE compression in most parts of Taiwan with a fan-shaped distribution. The rotation rate field reveals anticlockwise rotation in eastern and southern Taiwan while clockwise rotation in western and northern Taiwan, generally.
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This paper describes the main features of a view-based model of object recognition. The model tries to capture general properties to be expected in a biological architecture for object recognition. The basic module is a regularization network in which each of the hidden units is broadly tuned to a specific view of the object to be recognized.
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Alexander, N.; and Colgate, N. (2005). Customers' responses to retail brand extensions. Journal of Marketing Management. 21(3-4), pp.393-419 RAE2008
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Poolton, Nigel; Towlson, B.M.; Hamilton, B.; Evans, D.A., (2006) 'Synchrotron-laser interactions in hexagonal boron nitride: an examination of charge trapping dynamics at the boron K-edge', New Journal of Physics 8 pp.76 RAE2008
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Niniejsza praca zbiorowa stanowi wyraz uznania dla niezwykle ważnej roli nauczyciela w zapewnieniu efektywności procesu uczenia się i nauczania języków obcych na różnych poziomach kształcenia, ogniskując się w szczególności na jego obecnej sytuacji, problemach, którym musi stawiać czoła w codziennej pracy oraz wyzwaniom, z jakimi będzie się musiał zmierzyć w przyszłości. Teksty w niej zawarte podzielone zostały na osiem rozdziałów, w taki sposób, aby zilustrować wymagania, jakim sprostać musi nauczyciel języka obcego, jak również drogę, jaką przechodzi od chwili rozpoczęcia studiów neofilologicznych, poprzez podejmowane przez niego wysiłki zmierzające do podniesienia umiejętności językowych i dydaktycznych i zdobywania kolejnych stopni awansu zawodowego, aż po gotowość do samodzielnego poszukiwania najlepszych metod i technik nauczania, która jest niezbędna, aby mógł się on stać badaczem i innowatorem. I tak, w części pierwszej, zatytułowanej Wiedza, kompetencje i przekonania nauczyciela, znaleźć można opracowania, które pokazują, w jak wielu obszarach nauczyciel języka powinien być specjalistą, aby mógł skutecznie wypełniać powierzone mu role, a co za tym idzie, jak wieloaspektowe i wszechstronne musi być jego przygotowanie. Z kolei rozdział drugi, Autonomia i refleksja nauczycieli, zwraca uwagę na to, że kompetencje i umiejętności, choć niewątpliwie bardzo ważne, nie wystarczą do efektywnego nauczania w różnych sytuacjach, jeśli nie będą one na bieżąco uzupełniane, modyfikowane i dostosowywane do danej sytuacji, a nauczyciel nie będzie potrafił albo chciał sam decydować o doborze materiałów i przebiegu lekcji w danej grupie uczniów. Kolejne dwie części tomu, zatytułowane Kształcenie przyszłych nauczycieli języków obcych i Rozwój zawodowy nauczycieli języków obcych, poświęcone zostały celom, organizacji i sposobom realizacji programów mających na celu przygotowanie przyszłych nauczycieli a następnie podnoszenie ich kwalifikacji, a także kwestiom związanym z awansem zawodowym. W rozdziale piątym, Nauczyciel języka obcego podczas lekcji i zajęć, zamieszczono opracowania wskazujące na rolę nauczyciela w budowaniu relacji z uczniem, wprowadzaniu i ćwiczeniu materiału językowego, rozwijaniu sprawności oraz kształtowaniu charakteru dyskursu edukacyjnego. Z kolei rozdział szósty, Kształcenie uczniów ze specjalnymi potrzebami edukacyjnymi, porusza jakże istotną a jednocześnie jakże często pomijaną problematykę skutecznego nauczania uczniów z różnego rodzaju deficytami, czy to w klasie integracyjnej, czy w szkole specjalnej. I w końcu ostatnie dwa rozdziały, zatytułowane Badania nad osoba nauczyciela języków obcych i Poszukiwanie optymalnych rozwiązań dydaktycznych, podejmują kwestię prowadzenia badań empirycznych, zarówno tych dotyczących osoby nauczyciela, jak i tych podejmowanych przez nauczycieli z myślą o optymalizacji procesu dydaktycznego. Należy mieć nadzieję, że niniejszy tom przyczyni się do pełniejszego zrozumienia oraz docenienia roli nauczyciela w kształceniu językowym, a kompleksowe i wielostronne ujęcie tej tematyki sprawi, że stanie się on ważnym źródłem refleksji i punktem odniesienia dla badaczy, metodyków, studentów i samych nauczycieli.
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We give an explicit and easy-to-verify characterization for subsets in finite total orders (infinitely many of them in general) to be uniformly definable by a first-order formula. From this characterization we derive immediately that Beth's definability theorem does not hold in any class of finite total orders, as well as that McColm's first conjecture is true for all classes of finite total orders. Another consequence is a natural 0-1 law for definable subsets on finite total orders expressed as a statement about the possible densities of first-order definable subsets.
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BACKGROUND: Kinesin motors hydrolyze ATP to produce force and move along microtubules, converting chemical energy into work by a mechanism that is only poorly understood. Key transitions and intermediate states in the process are still structurally uncharacterized, and remain outstanding questions in the field. Perturbing the motor by introducing point mutations could stabilize transitional or unstable states, providing critical information about these rarer states. RESULTS: Here we show that mutation of a single residue in the kinesin-14 Ncd causes the motor to release ADP and hydrolyze ATP faster than wild type, but move more slowly along microtubules in gliding assays, uncoupling nucleotide hydrolysis from force generation. A crystal structure of the motor shows a large rotation of the stalk, a conformation representing a force-producing stroke of Ncd. Three C-terminal residues of Ncd, visible for the first time, interact with the central beta-sheet and dock onto the motor core, forming a structure resembling the kinesin-1 neck linker, which has been proposed to be the primary force-generating mechanical element of kinesin-1. CONCLUSIONS: Force generation by minus-end Ncd involves docking of the C-terminus, which forms a structure resembling the kinesin-1 neck linker. The mechanism by which the plus- and minus-end motors produce force to move to opposite ends of the microtubule appears to involve the same conformational changes, but distinct structural linkers. Unstable ADP binding may destabilize the motor-ADP state, triggering Ncd stalk rotation and C-terminus docking, producing a working stroke of the motor.
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BACKGROUND: The ability to write clearly and effectively is of central importance to the scientific enterprise. Encouraged by the success of simulation environments in other biomedical sciences, we developed WriteSim TCExam, an open-source, Web-based, textual simulation environment for teaching effective writing techniques to novice researchers. We shortlisted and modified an existing open source application - TCExam to serve as a textual simulation environment. After testing usability internally in our team, we conducted formal field usability studies with novice researchers. These were followed by formal surveys with researchers fitting the role of administrators and users (novice researchers) RESULTS: The development process was guided by feedback from usability tests within our research team. Online surveys and formal studies, involving members of the Research on Research group and selected novice researchers, show that the application is user-friendly. Additionally it has been used to train 25 novice researchers in scientific writing to date and has generated encouraging results. CONCLUSION: WriteSim TCExam is the first Web-based, open-source textual simulation environment designed to complement traditional scientific writing instruction. While initial reviews by students and educators have been positive, a formal study is needed to measure its benefits in comparison to standard instructional methods.
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BACKGROUND: Writing plays a central role in the communication of scientific ideas and is therefore a key aspect in researcher education, ultimately determining the success and long-term sustainability of their careers. Despite the growing popularity of e-learning, we are not aware of any existing study comparing on-line vs. traditional classroom-based methods for teaching scientific writing. METHODS: Forty eight participants from a medical, nursing and physiotherapy background from US and Brazil were randomly assigned to two groups (n = 24 per group): An on-line writing workshop group (on-line group), in which participants used virtual communication, google docs and standard writing templates, and a standard writing guidance training (standard group) where participants received standard instruction without the aid of virtual communication and writing templates. Two outcomes, manuscript quality was assessed using the scores obtained in Six subgroup analysis scale as the primary outcome measure, and satisfaction scores with Likert scale were evaluated. To control for observer variability, inter-observer reliability was assessed using Fleiss's kappa. A post-hoc analysis comparing rates of communication between mentors and participants was performed. Nonparametric tests were used to assess intervention efficacy. RESULTS: Excellent inter-observer reliability among three reviewers was found, with an Intraclass Correlation Coefficient (ICC) agreement = 0.931882 and ICC consistency = 0.932485. On-line group had better overall manuscript quality (p = 0.0017, SSQSavg score 75.3 +/- 14.21, ranging from 37 to 94) compared to the standard group (47.27 +/- 14.64, ranging from 20 to 72). Participant satisfaction was higher in the on-line group (4.3 +/- 0.73) compared to the standard group (3.09 +/- 1.11) (p = 0.001). The standard group also had fewer communication events compared to the on-line group (0.91 +/- 0.81 vs. 2.05 +/- 1.23; p = 0.0219). CONCLUSION: Our protocol for on-line scientific writing instruction is better than standard face-to-face instruction in terms of writing quality and student satisfaction. Future studies should evaluate the protocol efficacy in larger longitudinal cohorts involving participants from different languages.
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BACKGROUND: A Royal Statistical Society Working Party recently recommended that "Greater use should be made of numerical, as opposed to verbal, descriptions of risk" in first-in-man clinical trials. This echoed the view of many clinicians and psychologists about risk communication. As the clinical trial industry expands rapidly across the globe, it is important to understand risk communication in Asian countries. METHODS: We conducted a cognitive experiment about participation in a hypothetical clinical trial of a pain relief medication and a survey in cancer and arthritis patients in Singapore. In part 1 of the experiment, the patients received information about the risk of side effects in one of three formats (frequency, percentage and verbal descriptor) and in one of two sequences (from least to most severe and from most to least severe), and were asked about their willingness to participate. In part 2, the patients received information about the risk in all three formats, in the same sequence, and were again asked about their willingness to participate. A survey of preference for risk presentation methods and usage of verbal descriptors immediately followed. RESULTS: Willingness to participate and the likelihood of changing one's decision were not affected by the risk presentation methods. Most patients indicated a preference for the frequency format, but patients with primary school or no formal education were indifferent. While the patients used the verbal descriptors "very common", "common" and "very rare" in ways similar to the European Commission's Guidelines, their usage of the descriptors "uncommon" and "rare" was substantially different from the EU's. CONCLUSION: In this sample of Asian cancer and arthritis patients, risk presentation format had no impact on willingness to participate in a clinical trial. However, there is a clear preference for the frequency format. The lay use of verbal descriptors was substantially different from the EU's.
Variation in use of surveillance colonoscopy among colorectal cancer survivors in the United States.
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BACKGROUND: Clinical practice guidelines recommend colonoscopies at regular intervals for colorectal cancer (CRC) survivors. Using data from a large, multi-regional, population-based cohort, we describe the rate of surveillance colonoscopy and its association with geographic, sociodemographic, clinical, and health services characteristics. METHODS: We studied CRC survivors enrolled in the Cancer Care Outcomes Research and Surveillance (CanCORS) study. Eligible survivors were diagnosed between 2003 and 2005, had curative surgery for CRC, and were alive without recurrences 14 months after surgery with curative intent. Data came from patient interviews and medical record abstraction. We used a multivariate logit model to identify predictors of colonoscopy use. RESULTS: Despite guidelines recommending surveillance, only 49% of the 1423 eligible survivors received a colonoscopy within 14 months after surgery. We observed large regional differences (38% to 57%) across regions. Survivors who received screening colonoscopy were more likely to: have colon cancer than rectal cancer (OR = 1.41, 95% CI: 1.05-1.90); have visited a primary care physician (OR = 1.44, 95% CI: 1.14-1.82); and received adjuvant chemotherapy (OR = 1.75, 95% CI: 1.27-2.41). Compared to survivors with no comorbidities, survivors with moderate or severe comorbidities were less likely to receive surveillance colonoscopy (OR = 0.69, 95% CI: 0.49-0.98 and OR = 0.44, 95% CI: 0.29-0.66, respectively). CONCLUSIONS: Despite guidelines, more than half of CRC survivors did not receive surveillance colonoscopy within 14 months of surgery, with substantial variation by site of care. The association of primary care visits and adjuvant chemotherapy use suggests that access to care following surgery affects cancer surveillance.
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BACKGROUND: One year after the introduction of Information and Communication Technology (ICT) to support diagnostic imaging at our hospital, clinicians had faster and better access to radiology reports and images; direct access to Computed Tomography (CT) reports in the Electronic Medical Record (EMR) was particularly popular. The objective of this study was to determine whether improvements in radiology reporting and clinical access to diagnostic imaging information one year after the ICT introduction were associated with a reduction in the length of patients' hospital stays (LOS). METHODS: Data describing hospital stays and diagnostic imaging were collected retrospectively from the EMR during periods of equal duration before and one year after the introduction of ICT. The post-ICT period was chosen because of the documented improvement in clinical access to radiology results during that period. The data set was randomly split into an exploratory part used to establish the hypotheses, and a confirmatory part. The data was used to compare the pre-ICT and post-ICT status, but also to compare differences between groups. RESULTS: There was no general reduction in LOS one year after ICT introduction. However, there was a 25% reduction for one group - patients with CT scans. This group was heterogeneous, covering 445 different primary discharge diagnoses. Analyses of subgroups were performed to reduce the impact of this divergence. CONCLUSION: Our results did not indicate that improved access to radiology results reduced the patients' LOS. There was, however, a significant reduction in LOS for patients undergoing CT scans. Given the clinicians' interest in CT reports and the results of the subgroup analyses, it is likely that improved access to CT reports contributed to this reduction.