1,421 research outputs found
Effects of ionizing radiation on charge-coupled imagers
The effects of ionizing radiation on three different charge coupled imagers have been investigated. Device performance was evaluated as a function of total gamma ray dose. The principal failure mechanisms have been identified for each particular device structure. The clock and bias voltages required for high total dose operation of the devices are presented
Histological Chages of Testis and Caput Epididymis in the Goat after Cannulation of the Rete Testis
雄ヤギ5頭を用い, 精巣網カテーテル装着手術後の精巣および精巣上体頭の組織構造を観察するとともに精巣静脈血中のテストステロン濃度を調べた。カテーテル装着手術後の精巣は, いずれも萎縮し, 正常な精子形成過程が観察される精細管は少なかった。また, ライディヒ細胞の形態や染色性には異常は認められなかった。一方, 精巣上体頭では, 精巣上体管が萎縮し, 主細胞の高さは無傷のものよりも有意に減少した。同様の組織構造の変化は, 精巣輸出管を切除した場合の精巣および精巣上体頭でも認められた。精巣静脈血中のテストステロン濃度は無傷の場合94.4ng/mlであり, カテーテル装着手術後では86.5∿342.8ng/mlであった。 / The testis and caput epididymis of the goat after cannulation of the rete testis or efferentiectomy were examined histologically. The concentration of testosterone in testicular venous blood collected from the same animals was also measured by radioimmunoassay. After cannulation, seminiferous tubules showed a sign of degeneration, although no morphological change of Leydig cells was observed. Epididymal ducts were severely atrophied and the height of principal epithelial cells was significantly decreased. A similar damage was observed in the testis and epididymis after efferentiectomy. When the efferent duct bundle had been incompletely ligated at cannulation, or rete testis catheter was kept in place until sampling time, damages in the testis were less severe. And in the former case the epididymis was impaired less severely. The concentration of testosterone in testicular venous blood collected from an intact animal was 94.4ng/ml, while that obtained after cannulation was 86.5-342.8ng/ml. These results suggest that degeneration of germ cells in seminiferous tubules observed after cannulation of the rete testis or efferentiectomy may be caused by stagnation of rete testicular fluid in the tubules, and that testosterone in the fluid plays important roles in the maintenance of morphology and function of the principal cells in the caput epididymis
Decision-making capacity for treatment in psychiatric and medical in-patients: Cross-sectional, comparative study
BackgroundIs the nature of decision-making capacity (DMC) for treatment significantly different in medical and psychiatric patients?AimsTo compare the abilities relevant to DMC for treatment in medical and psychiatric patients who are able to communicate a treatment choice.MethodA secondary analysis of two cross-sectional studies of consecutive admissions: 125 to a psychiatric hospital and 164 to a medical hospital. The MacArthur Competence Assessment Tool – Treatment and a clinical interview were used to assess decision-making abilities (understanding, appreciating and reasoning) and judgements of DMC. We limited analysis to patients able to express a choice about treatment and stratified the analysis by low and high understanding ability.ResultsMost people scoring low on understanding were judged to lack DMC and there was no difference by hospital (P=0.14). In both hospitals there were patients who were able to understand yet lacked DMC (39% psychiatric v. 13% medical in-patients, P<0.001). Appreciation was a better ‘test’ of DMC in the psychiatric hospital (where psychotic and severe affective disorders predominated) (P<0.001), whereas reasoning was a better test of DMC in the medical hospital (where cognitive impairment was common) (P=0.02).ConclusionsAmong those with good understanding, the appreciation ability had more salience to DMC for treatment in a psychiatric setting and the reasoning ability had more salience in a medical setting.</jats:sec
Revisiting the Direct Sum Theorem and Space Lower Bounds in Random Order Streams
Estimating frequency moments and distances are well studied problems in the adversarial data stream model and tight space bounds are known for these two problems. There has been growing interest in revisiting these problems in the framework of random-order streams. The best space lower bound known for computing the frequency moment in random-order streams is by Andoni et al., and it is conjectured that the real lower bound shall be . In this paper, we resolve this conjecture. In our approach, we revisit the direct sum theorem developed by Bar-Yossef et al. in a random-partition private messages model and provide a tight space lower bound for any -pass algorithm that approximates the frequency moment in random-order stream model to a constant factor. Finally, we also introduce the notion of space-entropy tradeoffs in random order streams, as a means of studying intermediate models between adversarial and fully random order streams. We show an almost tight space-entropy tradeoff for distance and a non-trivial tradeoff for distances
Developing a Literature-Based Interview Script to Explore Mentorship Models in Medical Education Scholarship: A Collaboration Among Six Medical Institutions
Purpose
Medical education scholarship (MES), including medical education research, is meaningful work that benefits faculty, as well as learners and their institutions. Negotiating the terrain of MES – which often includes new languages, systems, and thought processes – requires consistent and effective mentorship. Unfortunately, effective mentorship for MES is lacking and an effective mentorship model has not been identified.
The purpose of this project was to conduct a literature search to inform and refine an interview script as the first part of a larger project that will identify elements of a model for MES. This abstract describes the systematic search process and recurring themes that emerged.
Methods
This project is funded by the Northeastern Group on Educational Affairs (NEGEA) and is a collaborative effort among 6 different medical institutions and 9 individuals with diverse professional backgrounds (physicians, librarians, educators).
The librarians created a search strategy using the grant proposal’s research question and inclusion/exclusion criteria, as well as additional terms provided by the team. Articles initially identified as focusing on basic and clinical science research mentorship in medicine also guided the creation of the strategy. PubMed, PsycINFO, ERIC, CINAHL, Web of Science, and the Cochrane Database of Systematic Reviews were searched.
Results
Search results were divided up among the 9 individuals and have gone through two stages of screening. After the second screening, a form was used to extract recurring themes. The final analysis of the themes was conducted by 2 members of the team and discussed by the whole team. The result includes an interview script grounded in evidence based practice.
Conclusion
The overall efforts of this project will provide a model for mentorship in MES. The model will enhance faculty development efforts in scholarship. Aside from the project’s purpose, this collaborative experience provided a unique faculty development opportunity for the researchers
'Un Bon Dessin Vaut Mieux Qu'un Long Discours' : the role and impact of cartoons in contemporary France
Cartoons have traditionally occupied an important place in French visual culture, and are now a permanent feature in even the most prestigious publications, including Le Monde, where they appear on the front page. Moreover, there is a long tradition of political cartooning which is firmly situated within the historical context of caricature and lampooning, which over the years has contributed to public debates on key issues such as politics, religion and social change. In this thesis, I focus on political cartoons and argue that the political cartoon is still significant as a cultural product and as a powerful journalistic medium at a time when the existence of the print media is threatened by new technological developments. In order to understand how cartoons remain a powerful mode of expression in the twenty-first century, I begin by examining the historical development of cartooning, tracing its origins in grotesque art, physiognomy and caricature. I then explore a number of events in early modern European history such as the Reformation and the French Revolution to show that the medium was used as a means of mass communication, to inform a largely illiterate public, incite protest and instigate rebellion through propaganda. I show how political graphics were used as effective political weapons against the ruling authorities, in the face of tight regulation such as censorship, and underline the French artists' commitment to defend their right of expression. As I demonstrate, this commitment continues to be pursued by contemporary French cartoonists such as Plantu who is dedicated to fighting for freedom of expression and promoting peace issues, under the banner of Le Monde and the United Nations. In analysing a corpus of Plantu's editorial creations, I underline theoretical perspectives for ‘reading' cartoons and illuminate the visual rhetoric used by cartoonists to communicate serious issues. I conclude with an assessment of the significant role that French cartoonists played during the 2006 Cartoons War to further highlight the impact of cartoons as a vehicle for political communication, and as a catalyst for debate in the twenty first century.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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