2,497 publications from this institution
Collaboration over the Internet depends on the ability of the members of a group to exchange data in a secure yet unobtrusive manner. WebDAVA is a system that allows the users to define their own access-control policies to network resources that they control, enabling secure data sharing within the enterprise. Our design allows users to selectively give fine-grain access to their resources without involving their system administrators. We accomplish this by using authorization credentials that define the users' privileges. Our prototype implements a file-sharing service, where users maintain sensitive-information folders and can allow others to access parts of these. Clients interact with the server over HTTP via a Java applet that transparently handles credential management. This mechanism allows users to share information with users not a priori known to the system, enabling administrator-free management.
Abstract This is a protocol to an umbrella review entitled, ‘Considering the methodological limitations and external validity issues of pharmacological drug trials in adult ADHD: An umbrella review (Open Protocol)’.
Small, high-speed and low power optical transmitter circuits are needed for optical interconnects to play a role in improving chip I/O bandwidth. This paper demonstrates two different transmitter designs fabricated in a 1V 90nm CMOS technology, one suitable for driving vertical cavity surface emitting lasers (VCSELs) and the other for driving multiple quantum well modulators (MQWMs). A four-tap current summing FIR equalizer extends VCSEL data rate for a given average current. It consumes 80mW at 18Gb/s operation and occupies 0.03mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2 </sup> area. The MQWM transmitter has a pulsed-cascode output stage capable of supplying a voltage swing of twice the 1V supply without overstressing thin-oxide core devices. It consumes 38mW at 16Gb/s and occupies 0.014mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> area
There is debate whether clinical trials with suboptimal power are justified and whether results from large studies are more reliable than the (combined) results of smaller trials. We quantified the error rates for evaluations based on single conventionally powered trials (80% or 90% power) versus evaluations based on the random-effects meta-analysis of a series of smaller trials. When a treatment was assumed to have no effect but heterogeneity was present, the error rates for a single trial were increased more than 10-fold above the nominal rate, even for low heterogeneity. Conversely, for meta-analyses on a series of trials, the error rates were correct. When selective publication was present, the error rates were always increased, but they still tended to be lower for a series of trials than single trials. We conclude that evidence of efficacy based on a series of (smaller) trials, may lower the error rates compared with using a single well-powered trial. Only when both heterogeneity and selective publication can be excluded, a single trial is able to provide conclusive evidence.
The authors present a fast single-ended BiCMOS sense circuit with CMOS output levels which is noise-insensitive enough to be used in a CMOS environment. A bipolar transistor is used in common-emitter configuration. Assuming that the bipolar transistor is conducting current, yet not saturated, a small voltage swing at the base is enough to turn the transistor off, and the collector voltage rises rapidly. An analog current mirror is used to prevent the bipolar transistor from saturating while maintaining a CMOS low-output voltage and to provide noise immunity. The full implementation of the sense circuit is shown.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
ii Chapter One: Introduction 1 Chapter Two: The HKM derivatives in the Qur’an 4 Ḥakīm 4 Ḥikmah 9 Ḥakam 12 Ḥakama and other verbs 14 Conclusion 20 Chapter Three: Hukam in the compositions of Kabir 23 Conclusion 30 Chapter Four: Guru Nanak and hukam 33 Historical and social context 33 Hukam in the compositions of Nanak 37 Conclusion 49 Chapter Five: The Sikh Gurus and hukam 52 The Sikh community as an historical entity 52 Hukam in the compositions of the Sikh Gurus 57 Conclusion 65 Chapter Six: The development of hukam 68 References 70 Bibliography 73
Background— Genome-wide association (GWA) platforms have yielded a rapidly increasing number of new genetic markers. The ability of these markers to improve prediction of clinically important outcomes is debated. Methods and Results— A systematic review was performed of GWA-derived markers associated with cardiovascular outcomes or other phenotypes that represent common established risk factors for cardiovascular outcomes. Sources of information included the National Human Genome Research Institute catalog of published GWA studies, and perusal of the eligible GWA articles, meta-analyses on the respective associations, and articles on the incremental predictive performance of common variants in the GWA era. A total of 95 eligible associations were retrieved from the National Human Genome Research Institute catalogue of published GWA studies as of September 2008. Of those 36 have statistical support of P <10 −7 . In depth evaluation of the respective articles shows 28 independent associations with such statistical support, pertaining to coronary artery disease, myocardial infarction, atrial fibrillation/flutter, prolongation of QT interval, as well as type 2 diabetes, body mass index, high-density lipoprotein levels, low-density lipoprotein levels, and nicotine dependence. Between-study heterogeneity is not taken into account usually, but it seems common and it would pose a challenge to generalizability across different populations for these markers. Still limited data are available in non-white populations. Effect sizes are small and may be even smaller in subsequent replications and meta-analysis. Population attributable fractions are substantial, given the large frequency of the risk alleles. However, individualized risk measures are typically very small (proportion of variance explained <1% per marker). When used in conjunction with traditional predictors, improvement in overall prediction (eg, area under the curve) or risk reclassification is limited, and subject to methodological caveats. Conclusions— Despite very promising signals in terms of statistical significance, evidence for improvement in cardiovascular prediction by currently available markers derived from GWA studies is sparse. Clinical use of such markers currently would be premature.
Our results exclude the possibility that the autoantibodies evaluated increase substantially the risk of death among very elderly subjects in good functional condition.
We examined the extent to which the scientific workforce in different fields was engaged in publishing COVID-19-related papers. According to Scopus (data cut, 1 August 2021), 210 183 COVID-19-related publications included 720 801 unique authors, of which 360 005 authors had published at least five full papers in their career and 23 520 authors were at the top 2% of their scientific subfield based on a career-long composite citation indicator. The growth of COVID-19 authors was far more rapid and massive compared with cohorts of authors historically publishing on H1N1, Zika, Ebola, HIV/AIDS and tuberculosis. All 174 scientific subfields had some specialists who had published on COVID-19. In 109 of the 174 subfields of science, at least one in 10 active, influential (top 2% composite citation indicator) authors in the subfield had authored something on COVID-19. Fifty-three hyper-prolific authors had already at least 60 (and up to 227) COVID-19 publications each. Among the 300 authors with the highest composite citation indicator for their COVID-19 publications, most common countries were USA ( n = 67), China ( n = 52), UK ( n = 32) and Italy ( n = 18). The rapid and massive involvement of the scientific workforce in COVID-19-related work is unprecedented and creates opportunities and challenges. There is evidence for hyper-prolific productivity.
Non-randomised studies assessing COVID-19 vaccine effectiveness need to consider multiple factors that may generate spurious estimates due to bias or genuinely modify effectiveness. These include pre-existing immunity, vaccination misclassification, exposure differences, testing, disease risk factor confounding, hospital admission decision, treatment use differences, and death attribution. It is useful to separate whether the impact of each factor admission decision, treatment use differences, and death attribution. Steps and measures to consider for improving vaccine effectiveness estimation include registration of studies and of analysis plans; sharing of raw data and code; background collection of reliable information; blinded assessment of outcomes, e.g. death causes; using maximal/best information in properly-matched studies, multivariable analyses, propensity analyses, and other models; performing randomised trials, whenever possible, for suitable questions, e.g. booster doses or comparative effectiveness of different vaccination strategies; living meta-analyses of vaccine effectiveness; better communication with both relative and absolute metrics of risk reduction and presentation of uncertainty; and avoidance of exaggeration in communicating results to the general public.
