Diabetic retinopathy: current and future methods for early screening from a retinal hemodynamic and geometric approach

Diabetic retinopathy (DR) is a major disease and is the number one cause of blindness in the UK. In England alone, 4200 new cases appear every year and 1280 lead to blindness. DR is a result of diabetes mellitus, which affects the retina of the eye and specifically the vessel structure. Elevated levels of glucose cause a malfunction in the cell structure, which affects the vessel wall and, in severe conditions, leads to their breakage. Much research has been carried out on detecting the different stages of DR but not enough versatile research has been carried out on the detection of early DR before the appearance of any lesions. In this review, the authors approach the topic from the functional side of the human eye and how hemodynamic factors that are impaired by diabetes affect the vascular structur

Untangling the effects of overexploration and overexploitation on organizational performance: The moderating role of environmental dynamism

Because a firm's optimal knowledge search behavior is determined by unique firm and industry conditions, organizational performance should be contingent oil the degree to which a firm's actual level of knowledge search deviates from the optimal level. It is thus hypothesized that deviation from the optimal search, in the form of either overexploitation or overexploration, is detrimental to organizational performance. Furthermore, the negative effect of search deviation oil organizational performance varies with environmental dynamism: that is, overexploitation is expected to become more harmful. whereas overexploration becomes less so with all increase in environmental dynamism. The empirical analyses yield results consistent with these arguments. Implications for research and practice are correspondingly discussed

Cementation of residue ion exchange resins at Rocky Flats

Ion exchange resins have been used to purify nitric acid solutions of plutonium at Rocky Flats since the 1950s. Spent ion exchange resins were retained for eventual recovery of residual plutonium, typically by incineration followed by the aqueous extraction of plutonium from the resultant ash. The elimination of incineration as a recovery process in the late 1980s and the absence of a suitable alternative process for plutonium recovery from resins led to a situation where spent ion exchange resins were simply placed into temporary storage. This report describes the method that Rocky Flats is currently using to stabilize residue ion exchange resins. The objective of the resin stabilization program is: (1) to ensure their safety during interim storage at the site, and (2) to prepare them for ultimate shipment to the Waste Isolation Pilot Plant (WIPP) in New Mexico. Included in the discussion is a description of the safety concerns associated with ion exchange resins, alternatives considered for their stabilization, the selection of the preferred treatment method, the means of implementing the preferred option, and the progress to date

Functional Neuroimaging Correlates of Burnout among Internal Medicine Residents and Faculty Members

Contains fulltext : 125473.pdf (publisher's version ) (Open Access)Burnout is prevalent in residency training and practice and is linked to medical error and suboptimal patient care. However, little is known about how burnout affects clinical reasoning, which is essential to safe and effective care. The aim of this study was to examine how burnout modulates brain activity during clinical reasoning in physicians. Using functional Magnetic Resonance Imaging (fMRI), brain activity was assessed in internal medicine residents (n = 10) and board-certified internists (faculty, n = 17) from the Uniformed Services University (USUHS) while they answered and reflected upon United States Medical Licensing Examination and American Board of Internal Medicine multiple-choice questions. Participants also completed a validated two-item burnout scale, which includes an item assessing emotional exhaustion and an item assessing depersonalization. Whole brain covariate analysis was used to examine blood-oxygen-level-dependent (BOLD) signal during answering and reflecting upon clinical problems with respect to burnout scores. Higher depersonalization scores were associated with less BOLD signal in the right dorsolateral prefrontal cortex and middle frontal gyrus during reflecting on clinical problems and less BOLD signal in the bilateral precuneus while answering clinical problems in residents. Higher emotional exhaustion scores were associated with more right posterior cingulate cortex and middle frontal gyrus BOLD signal in residents. Examination of faculty revealed no significant influence of burnout on brain activity. Residents appear to be more susceptible to burnout effects on clinical reasoning, which may indicate that residents may need both cognitive and emotional support to improve quality of life and to optimize performance and learning. These results inform our understanding of mental stress, cognitive control as well as cognitive load theory

Fast and Robust Features for Prosodic Classification

In our previous research, we have shown that prosody can be used to dramatically improve the performance of the automatic speech translation system Verbmobil [5, 7, 8]. In Verbmobil, prosodic information is made available to the different modules of the system by annotating the output of a word recognizer with prosodic markers. These markers are determined in a classification process. The computation of the prosodic features used for classification was previously based on a time alignment of the phoneme sequence of the recognized words. The phoneme segmentation was needed for the normalization of duration and energy features. This time alignment was very expensive in terms of computational effort and memory requirement. In our new approach the normalization is done on the word level with precomputed duration and energy statistics, thus the phoneme segmentation can be avoided. With the new set of prosodic features better classification results can be achieved, the features extraction can be sped up by 64%, and the memory requirements are even reduced by 92%

Relationship of neuroimaging to typical sleep times during a clinical reasoning task: a pilot study

Item does not contain fulltextBACKGROUND: Sleep deprivation and fatigue have been associated with medical errors, clinical performance decrements, and reduced quality of life for both practicing physicians and medical students. Greater understanding of the impact of sleep quantity on clinical reasoning could improve patient care. The purpose of our pilot study was to examine relationships between clinical reasoning (assessed by functional magnetic resonance imaging) and sleep time (measured in different ways by actigraphy) while answering multiple-choice questions (MCQs) from licensing agencies. METHODS: Residents and faculty were administered a clinical reasoning exercise (MCQs from licensing bodies) during functional magnetic resonance imaging. Usual sleep patterns were sampled with actigraphy. Covariate analysis was used to examine the relationship between sleep duration (mean sleep, minimum sleep, maximum sleep) and brain activity during clinical reasoning (solving MCQs from licensing bodies). RESULTS: The mean sleep time over the duration of monitoring for the group was 7.19 hours (SD 0.66) with a range of 6.1 to 8.1 hours (internal medicine faculty 7.1 hours, SD 0.41; internal medicine residents 7.27 hours, SD 0.92). There was a negative relationship between activation in the prefrontal cortex and minimum sleep time while reflecting on MCQs. CONCLUSION: Our findings provide evidence that the quantity of sleep can modulate brain activity while completing a clinically meaningful task that should be confirmed in larger studies. Our findings suggest that the construct of sleepiness may be more complex than appreciated by many and that the most important of these sleep measures in terms of outcomes remains to be determined