This paper presents a technique for characterizing the statistical properties and spectrum of power supply noise using only two on-chip low-throughput samplers. The samplers utilize a voltage-controlled oscillator to perform high-resolution analog-to-digital conversion with minimal hardware. The measurement system is implemented in a 0.13-/spl mu/m process along with a high-speed link transceiver. Measured results from this chip validate the accuracy of the measurement system and elucidate several aspects of power supply noise, including its cyclostationary nature.
We aimed to assess which factors correlate with collaborative behavior and whether such behavior associates with scientific impact (citations and becoming a principal investigator). We used the R index which is defined for each author as log(Np)/log(I1), where I1 is the number of co-authors who appear in at least I1 papers written by that author and Np are his/her total papers. Higher R means lower collaborative behavior, i.e. not working much with others, or not collaborating repeatedly with the same co-authors. Across 249,054 researchers who had published ≥30 papers in 2000-2015 but had not published anything before 2000, R varied across scientific fields. Lower values of R (more collaboration) were seen in physics, medicine, infectious disease and brain sciences and higher values of R were seen for social science, computer science and engineering. Among the 9,314 most productive researchers already reaching Np ≥ 30 and I1 ≥ 4 by the end of 2006, R mostly remained stable for most fields from 2006 to 2015 with small increases seen in physics, chemistry, and medicine. Both US-based authorship and male gender were associated with higher values of R (lower collaboration), although the effect was small. Lower values of R (more collaboration) were associated with higher citation impact (h-index), and the effect was stronger in certain fields (physics, medicine, engineering, health sciences) than in others (brain sciences, computer science, infectious disease, chemistry). Finally, for a subset of 400 U.S. researchers in medicine, infectious disease and brain sciences, higher R (lower collaboration) was associated with a higher chance of being a principal investigator by 2016. Our analysis maps the patterns and evolution of collaborative behavior across scientific disciplines.
Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
Bisim is an event-driven, transistor-level, logic simulator that models both the logical and timing characteristics of custom emitter-coupled-logic/current-mode-logic circuits. Node voltages are represented by piecewise-linear waveforms, transistor currents are represented by piecewise-constant waveforms, and transistors are modeled as voltage-controlled current switches. Bisim's realistic circuit models enable it to simulate correctly a wide variety of circuit topologies while retaining much of the speed of higher level simulators.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
The current goal of interferon treatment for chronic hepatitis C is to normalize alanine aminotransferase (ALT) and to eradicate detectable viral RNA. Many patients do not achieve this objective during treatment, and most do not sustain these outcomes after interferon is discontinued. However, biochemical or virological responses to interferon may not reflect accurately the histological consequences of therapy. The aim of this study was to determine the extent to which the biochemical measures reflect the histological outcomes in the treatment of hepatitis C with interferon alfa using a meta-analysis of diagnostic test characteristics. The data sources were English and non-English language studies retrieved from Medline (from 1966 to December 1995). The study selection included studies in which interferon alfa was used for treatment of chronic hepatitis C with liver biopsies performed before and after therapy. Data on histological and biochemical outcomes were extracted independently by two reviewers. Two separate criteria were used for defining histological response. When strict definitions of histological improvement were considered, histology improved in 28% (95% confidence interval [95% CI], 17%-43%) of patients after interferon treatment. The sensitivity and specificity of the ALT for determining histological change were 70% (95% CI, 56%-81%) and 66% (95% CI, 56%-75%), respectively. As many as 17% (95% CI, 9%-30%) of subjects with an abnormal ALT at the end of therapy may have improved histologically after interferon therapy. When less stringent definitions of histological improvement were considered, 62% (95% CI, 51%-72%) improved after therapy. The sensitivity and specificity of the ALT for determining histological change were 55% (95% CI, 44%-65%) and 75% (95% CI, 67%-81%), respectively. As many as 51% (95% CI, 38%-64%) may have improved, despite failure to normalize ALT. A substantial number of patients may improve histologically after interferon therapy. The significance of histological changes observed after interferon therapy must be weighed against the limitations of liver biopsy and the uncertain natural history of hepatitis C. Nevertheless, the ALT does not always reflect liver histology accurately after interferon alfa treatment and may underestimate histological improvement.
Система комплексной поддержки и сопровождения научного журнала Elpub позволяет запустить двуязычный сайт журнала со встроенной системой электронной редакции в соответствии с лучшими издательскими практиками, а так же предусматривает техническую и методическую поддержку со стороны специалистов НЭИКОН.
The term “obesity paradox” is a figure of speech, not a scientific term. The term has no precise definition and has been used to describe numerous observations that have little in common other than the finding of an association of obesity with a favorable outcome. The terminology has led to misunderstandings among researchers and the public alike. It's time for authors and editors to abandon the use of this term. Simply labeling counterintuitive findings as the “obesity paradox” adds no value. Unexpected findings should not be viewed negatively; such findings can lead to new knowledge, better treatments, and scientific advances.
Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
This is the first in a series of 3 articles serving as an introduction to clinicians wishing to read and critically appraise genetic association studies. We summarize the key concepts in genetics that clinicians must understand to review these studies, including the structure of DNA, transcription and translation, patterns of inheritance, Hardy-Weinberg equilibrium, and linkage disequilibrium. We review the types of DNA variation, including single-nucleotide polymorphisms (SNPs), insertions, and deletions, and how these can affect protein function. We introduce the idea of genetic association for both single-candidate gene and genome-wide association studies, in which thousands of genetic variants are tested for association with disease. We use the APOE polymorphism and its association with dementia as a case study to demonstrate the concepts and introduce the terminology used in this field. The second and third articles will focus on issues of validity and applicability.
This is a protocol for the project entitled "FDA and EMA clinical research guidelines: Assessment of trial design recommendations for pivotal psychiatric drug trials".
Some interventions for smoking cessation such as quit smoking aids show sex-specific effects on outcomes, but behavioral interventions such as mindfulness-based interventions (MBIs) for smoking cessation lack formal reporting of sex-intervention tests of interaction to date. To address this gap, we conducted a secondary analysis of a RCT dataset (N = 213), recruiting participants from California, to statistically test a sex-intervention interaction effect on complete 7-day point prevalence abstinence (PPA), proportion of days abstinent, and daily cigarettes smoked. Smoking was assessed using the timeline follow back method spanning the four weeks following a daily 14-day app-based intervention and a planned smoking quit date immediately following the intervention phase. All models adjusted for baseline nicotine dependence. The study groups had comparable sex proportions (MBI: 56 % female; control: 55 % female) and the ratio of outcome assessment completion by group was not dependent on sex. Adjusted analyses revealed a significant sex-intervention interaction effect for daily cigarettes smoked ([female coded 1]: two-way interaction effect IRR = 0.59, 95 % CI: 0.46-0.77, p < 0.0001; effect for female: IRR = 0.68, 95 % CI: 0.57-0.81, effect for male: IRR = 1.14, 95 % CI: 0.95-1.37), but not for complete 7-day PPA ([female coded 1] two-way interaction effect OR = 1.24, 95 % CI: 0.31-4.89, p = 0.76) or proportion of total days abstinent ([female coded 1] two-way interaction effect OR = 1.97, 95 % CI: 0.53-7.37, p = 0.31). Females, but not males, allocated to a daily app-based MBI with a quit plan and quit aid workbook smoked fewer cigarettes per day compared to females in the control group. Males, but not females, showed significantly less use of the MBI app compared to the control app.
Randomized trials are an excellent research design with major advantages. However, randomized trials are not immune to biases, and inferences from them may be sometimes flawed or irrelevant. The present review addresses, in brief, some of the major threats to the credibility and relevance of the results of clinical trials: power problems, biases affecting internal validity (poor design, conduct, and analysis), biases affecting the total randomized evidence on a specific topic (publication bias and selective outcome and analysis reporting bias), lack of relevance, poor generalizability, and biases in the interpretation of the results.
