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921.
Faculty at research universities are evaluated on a number of productivity measures including their ability to conduct research, teach, and engage in service. Research outcomes include publishing research results and acquiring grants and contracts to conduct additional research. While it is assumed that researchers who are awarded grants are more likely to publish research results, there is little research investigating the ways in which grants affect outcomes or how principal investigators differ from researchers who do not hold research grants or those who are co-principal investigators. This research seeks to understand if principal investigators are more or less productive than co-principal investigators and those who do not have grants, and if so, what explains that variation in productivity. It also examines whether women PIs are more or less productive than men PIs. This research uses longitudinal data drawn from an NSF funded survey of academic scientists in Carnegie-designated Research I universities in six fields: biology, chemistry, computer science, earth and atmospheric sciences, electrical engineering, and physics. From this national random sample of men and women scientists and engineers we investigate whether there is variation in the production of outcomes (e.g. publications, teaching, and training graduate students) among PIs, co-PIs, and other researchers. Findings show that productivity and outcomes vary significantly for PIs, co-PIs and by sex. 相似文献
922.
Various explanations have been offered regarding the causes of the current global economic crisis that was spawned by the collapse of mortgage-based securities in the U.S. that were sold world-wide and that contained "toxic assets" comprised of subprime loans. There is ample evidence that such loans were originated through fraud. Firms recorded huge profits, and executives were awarded large bonuses even though some had led their companies into bankruptcy and plunged both the U.S. and global economies into the greatest recession since the Great Depression. This paper assesses the reasons why there have been no major prosecutions to date, and compares the U.S. government's response to that in the savings and loan crisis. It analyzes the influence of large financial institutions on lawmaking, regulation, and the allocation of enforcement resources, the continued general lack of understanding of financial fraud including control fraud, and problems related to the higher status and power of potential defendants. 相似文献
923.
With the increasing dispersion of intellectual property comes the intellectual property rights owner's continued desire to retain that part of the equation for which the bargain was struck. In terms of patents, the patentee strikes a deal to disclose the invention to the public in exchange for a monopoly over its use for a limited term. Copyright holders contribute their works to the intellectual pool receiving value by sale, lease or license. In 2012–13, the U.S. Supreme Court was tasked with delineating the realms of two intellectual property exhaustion doctrines and answering the question of where to draw the line with regard to an IP owner's ability to control the protected invention or work via patent or copyright, respectively. In one case, the Court permitted the intellectual property owner to restrict a subsequent purchaser's use of the product subject to protection, while in the other case the Court rejected the intellectual property owner's attempt to control the downstream use or resale of the product. This article discusses the relevant intellectual property exhaustion doctrines, analyzes and reconciles the Court's decisions in these cases, and provides guidance for navigating restrictions on use of U.S. protected products and works around the globe. 相似文献
924.
Sax JK 《Annals of health law / Loyola University Chicago, School of Law, Institute for Health Law》2006,15(1):1-36, table of contents
This article presents an innovative study of the effect of individual states and private institutes in pushing forward stem cell research despite a federal ban on creating new stem cell lines. The author analyzes the impact of state legislation, proposing that states are reacting to federal policy by serving as laboratories for what is traditionally federally funded biomedical research. 相似文献
925.
Urine is often the sample of choice for drug screening in aviation/general forensic toxicology and in workplace drug testing. In some instances, the origin of the submitted samples may be challenged because of the medicolegal and socioeconomic consequences of a positive drug test. Methods for individualization of biological samples have reached a new boundary with the application of the polymerase chain reaction (PCR) in DNA profiling, but a successful characterization of the urine specimens depends on the quantity and quality of DNA present in the samples. Therefore, the present study investigated the influence of storage conditions, sample volume, concentration modes, extraction procedures, and chemical preservations on the quantity of DNA recovered, as well as the success rate of PCR-based genotyping for DQA1 and PM loci in urine. Urine specimens from male and female volunteers were divided and stored at various temperatures for up to 30 days. The results suggested that sample purification by dialfiltration, using 3000-100,000 molecular weight cut-off filters, did not enhance DNA recovery and typing rate as compared with simple centrifugation procedures. Extraction of urinary DNA by the organic method and by the resin method gave comparable typing results. Larger sample volume yielded a higher amount of DNA, but the typing rates were not affected for sample volumes between 1 and 5 ml. The quantifiable amounts of DNA present were found to be greater in female (14-200 ng/ml) than in male (4-60 ng/ml) samples and decreased with the elapsed time under both room temperature (RT) and frozen storage. Typing of the male samples also demonstrated that RT storage samples produced significantly higher success rates than that of frozen samples, while there was only marginal difference in the DNA typing rates among the conditions tested using female samples. Successful assignment of DQA1 + PM genotype was achieved for all samples of fresh urine, independent of gender, starting sample volume, or concentration method. Preservation by 0.25% sodium azide was acceptable for sample storage at 4 degrees C during a period of 30 days. For longer storage duration, freezing at -70 degrees C may be more appropriate. Thus, the applicability of the DQA1 + PM typing was clearly demonstrated for individualization of urine samples. 相似文献
926.
Mitochondrial DNA regions HVI and HVII population data. 总被引:2,自引:0,他引:2
B Budowle M R Wilson J A DiZinno C Stauffer M A Fasano M M Holland K L Monson 《Forensic science international》1999,103(1):23-35
Data from 1393 unrelated individuals have been compiled from eight population groups: African Americans, Africans (Sierra Leone), U.S. Caucasians, Austrians, French, Hispanics, Japanese, and Asian Americans. The majority of the mtDNA sequences were observed only once within each population group (i.e., ranging from a low of 60.3% (35/58) of the Asian American sequences to a high of 85.3% (93/109) of the French sequences). Genetic diversity ranged from 0.990 in the African sample to 0.998 in African Americans. Random match probability ranged from 2.50% in the Asian American sample to 0.52% in U.S. Caucasians. The average number of nucleotide differences between individuals in a database is greatest for the African American and African samples (14.1 and 13.1, respectively), and the least variable are the Caucasians (ranging from 7.2 to 8.4). Substitutions are the predominate polymorphism, and at least 92% of the substitutions are transitions. The most prevalent transversions are As substituted for Cs and Cs substituted for As. For most population groups these transversions occurred predominately in the HVI region; however, the African, African American, and Hispanic samples also demonstrated a large portion of their C to A and A to C transversions in the HVII region (at sites 186 and/or 189). Most insertions occur in the HVII region at sites 309.1 and 315.1, within a stretch of C's. Insertions of an additional C are common in all population groups. The sequence data were converted to SSO mtDNA types and compared with population data on Caucasians, Africans, Asians, Japanese, and Mexicans described by Stoneking et al. [M. Stoneking, D. Hedgecock, R.G. Higuchi, L. Vigilant, H.A. Erlich, Population variation of human mtDNA control region sequences detected by enzymatic amplification and sequence-specific oligonucleotide probes, Am. J. Hum. Genet. 48 (1991) 370-382] using an R x C contingency table test. Differences between major population groups (i.e., between African, Caucasian, and Asian) are quite evident, and similar ethnic population groups carried similar SSO polymorphism frequencies. There were only a few SSO types that showed significant differences between subpopulation groups. The SSO data alone can not be used to describe the population genetics with complete sequence data. However, the results of the SSO comparisons are similar to other analyses, and differences in sequence data in regions HVI and HVII are greater between major population groups than between subgroups. 相似文献
927.
R. J. Mourits N. van den Berg M. Rodríguez-Girondo K. Mandemakers P. E. Slagboom M. Beekman 《The History of the Family》2020,25(3):484-526
ABSTRACT Studies have shown that long-lived individuals seem to pass their survival advantage on to their offspring. Offspring of long-lived parents had a lifelong survival advantage over individuals without long-lived parents, making them more likely to become long-lived themselves. We test whether the survival advantage enjoyed by offspring of long-lived individuals is explained by environmental factors. 101,577 individuals from 16,905 families in the 1812–1886 Zeeland cohort were followed over time. To prevent that certain families were overrepresented in our data, disjoint family trees were selected. Offspring was included if the age at death of both parents was known. Our analyses show that multiple familial resources are associated with survival within the first 5 years of life, with stronger maternal than paternal effects. However, between ages 5 and 100 both parents contribute equally to offspring’s survival chances. After age 5, offspring of long-lived fathers and long-lived mothers had a 16-19% lower chance of dying at any given point in time than individuals without long-lived parents. This survival advantage is most likely genetic in nature, as it could not be explained by other, tested familial resources and is transmitted equally by fathers and mothers. 相似文献
928.
AbstractThis article reports on timing the adverse effects of black carbon released into the atmosphere from biomass combustion, vehicular emissions and local combustion sources. Black carbon contributes to global warming through its light absorption capacity, has a direct and indirect impact on climate and public health, and will result in ongoing environmental damages and claims. The authors studied measurements of black carbon taken in Delhi, India during 2016 and 2017, and reports on seasonal factors that contribute to higher emissions. 相似文献
929.
Kristopher D. Wisniewski Ph.D. Nicholas Cooper M.Sc. Vivienne Heaton Ph.D. Colin Hope B.Sc.; M.Sc. Duncan Pirrie Ph.D. Andrew J. Mitten M.Geo. Jamie K. Pringle Ph.D. 《Journal of forensic sciences》2019,64(5):1530-1539
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations. 相似文献
930.