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121.
A challenge in automatic speaker verification is to create a system that is robust to the effects of vocal ageing. To observe the ageing effect, a speaker's voice must be analysed over a period of time, over which, variation in the quality of the voice samples is likely to be encountered. Thus, in dealing with the ageing problem, the related issue of quality must also be addressed. We present a solution to speaker verification across ageing by using a stacked classifier framework to combine ageing and quality information with the scores of a baseline classifier. In tandem, the Trinity College Dublin Speaker Ageing database of 18 speakers, each covering a 30–60 year time range, is presented. An evaluation of a baseline Gaussian Mixture Model–Universal Background Model (GMM–UBM) system using this database demonstrates a progressive degradation in genuine speaker verification scores as ageing progresses. Consequently, applying a conventional threshold, determined using scores at the time of enrolment, results in poor long-term performance. The influence of quality on verification scores is investigated via a number of quality measures. Alongside established signal-based measures, a new model-based measure, Wnorm, is proposed, and its utility is demonstrated on the CSLU database. Combining ageing information with quality measures and the scores from the GMM–UBM system, a verification decision boundary is created in score-ageing-quality space. The best performance is achieved by using scores and ageing in conjunction with the new Wnorm quality measure, reducing verification error by 45% relative to the baseline. This work represents the first comprehensive analysis of speaker verification on a longitudinal speaker database and successfully addresses the associated variability from ageing and quality arte-facts. 相似文献
122.
This study investigates the effects of large-scale research funding from the Japanese government on the research outcomes of university researchers. To evaluate the effects, we use the difference-in-differences estimator and measure research outcomes in terms of number of papers and citation counts per paper. Our analysis shows that the funding program led to an increase in the number of papers in some fields and an increase in the citation counts in the other fields. A comparison of our estimation results with assessment data obtained from peer reviews showed important differences. Since the characteristics of research vary according to the field, bibliometrics analysis should be used along with the peer review method for a more accurate analysis of research impact. 相似文献
123.
Colby A. Souders Sharon E. Maynard Jing Yan Yang Wang Naomi K. Boatright Jessica Sedan David Balyozian Peter S. Cheslock Deborah C. Molrine Tiffany A. Moore Simas 《International journal of molecular sciences》2015,16(6):12436-12453
Angiogenic biomarkers, including soluble fms-like tyrosine kinase 1 (sFlt1), are thought to be predictors of preeclampsia onset; however, improvement is needed before a widespread diagnostic test can be utilized. Here we describe the development and use of diagnostic monoclonal antibodies specific to the two main splice variants of sFlt1, sFlt1-1 and sFlt1-14. These antibodies were selected for their sensitivity and specificity to their respective sFlt1 isoform in a capture ELISA format. Data from this pilot study suggest that sFlt1-1 may be more predictive of preeclampsia than total sFlt1. It may be possible to improve current diagnostic platforms if more specific antibodies are utilized. 相似文献
124.
Little research has examined different dimensions of narcissism that may parallel psychopathy facets in criminally involved individuals. In this study, we examined the pattern of relationships between grandiose and vulnerable narcissism, assessed using the Narcissistic Personality Inventory–16 and the Hypersensitive Narcissism Scale, respectively, and the four facets of psychopathy (interpersonal, affective, lifestyle, and antisocial) assessed via the Psychopathy Checklist: Screening Version. As predicted, grandiose and vulnerable narcissism showed differential relationships to psychopathy facets, with grandiose narcissism relating positively to the interpersonal facet of psychopathy and vulnerable narcissism relating positively to the lifestyle facet of psychopathy. Paralleling existing psychopathy research, vulnerable narcissism showed stronger associations than grandiose narcissism to (a) other forms of psychopathology, including internalizing and substance use disorders, and (b) self- and other-directed aggression, measured with the Life History of Aggression and the Forms of Aggression Questionnaire. Grandiose narcissism was nonetheless associated with social dysfunction marked by a manipulative and deceitful interpersonal style and unprovoked aggression. Potentially important implications for uncovering etiological pathways and developing treatment interventions for these disorders in externalizing adults are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
125.
研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程度与年龄、性别和生理状态有关,在此我们以普通生活的成人作为基准。杂粮中的营养成分,苋的热量358kcal、蛋白质12.7g、脂肪6.0g、糖质64.9g、食物纤维7.4g、Na 1.0mg、P540mg、Fe 9.4mg、Ca 160mg、K 600mg、Cu 0.92mg、Zn 5.8mg、Mn 6.14mg、维生素A 2.0ug以及微量的维生素C。经过研讨设计了营养平衡最佳的食谱为:糙米200g、苋50g、andeskinua50g、大豆110g、甘薯200g、绿黄色蔬菜(小青菜)300g、鸡蛋55g以及泥鳅100g。食用这个食谱可以摄取热量2007 kcal(是基准摄取量的100%),其他营养成分的摄取量与基准摄取量相比分别为:蛋白质173%、脂肪72%、碳水化物105%、K 332%、Ca262%、Mg 267%、P 250%、Fe 420%、Zn 183%、Cu 343%、VA 126%、VD 100%、VE 142%、VK 940%、VB1237%、VB2174%、烟碱酸201%、VB6218%、VB12375%、叶酸350%、泛酸160%、VC 176%、食物纤维185%、盐分5%以及Mn 273%。不足的盐分可以使用调味料来补充。氨基酸的摄取量推测是基准值的100%。蛋白质:脂肪:碳水化物的比例是19.0∶18.0∶63.0,与理想的平衡比接近。 相似文献
126.
Comments on an article by Marshall et al. (see record 2007-07130-003). Marshall et al. (2007) believe that widespread media-induced PTSD calls for a new paradigm for understanding traumatic stress. But do the post-9/11 studies really document a nationwide epidemic of what Young (in press) wryly calls "PTSD of the virtual kind"? For several reasons, we are skeptical. We question the need for a new paradigm to explain "virtual PTSD" because we question the evidence supporting its existence. Although at least some people directly exposed to danger surely developed PTSD in response to the terrorist attacks, there are good reasons to doubt whether an epidemic swept the nation in the wake of 9/11. Contrary to Marshall's (2006) view, our skepticism is neither ethically problematic nor indicative of "denial of human suffering" (p. 627). Instead, our skepticism is driven by the absence of convincing evidence that such an epidemic occurred. The more plausible interpretation of the data is that the responses of community residents reflect normal, temporary distress responses to a shocking event, not medical symptoms indicative of psychiatric illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
Naomi H. Bennett Holly R. Chinnery Laura E. Downie Lisa J. Hill Liam M. Grover 《Advanced functional materials》2020,30(14)
Eye drops are the most common and inexpensive approach to topical ocular drug delivery. Eye drops offer a noninvasive treatment strategy; however, this can be detrimental to therapeutic efficacy when compared to invasive methods such as surgeries, implants, and injections. Improvements to the efficacy of the topical delivery of drugs to ocular tissues are currently being explored and much of this work centers on adjusting the formulation of the eye drops and prolonging the bioavailability of the therapeutic agent. This is often in preference to improving other patient‐focused or clinical factors. In this progress report, conventional, commercially available polymer eye drops are explored and the ability for current and future innovations to maintain the existing benefits of eye drops to the patient is assessed. The final materials and form of the drops (liquid, gel, or other) and the immunological implications for the user are explored. There is currently no consensus for how to most effectively improve the ocular retention and drug delivery capabilities of eye drops, but key issues are highlighted in the context of current methods under development, and potential questions and considerations for future innovations are raised. 相似文献
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