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Background: The parallel decline of mobility and cognition with ageing is explained in part by shared brain structural changes that are related to fitness. However, the temporal sequence between fitness, brain structural changes and mobility loss has not been fully evaluated.Methods: Participants were from the Baltimore Longitudinal Study of Aging, aged 60 or older, initially free of cognitive and mobility impairments, with repeated measures of fitness (400-m time), mobility (6-m gait speed) and neuroimaging markers over 4 years (n = 332). Neuroimaging markers included volumes of total brain, ventricles, frontal, parietal, temporal and subcortical motor areas, and corpus callosum. Autoregressive models were used to examine the temporal sequence of each brain volume with mobility and fitness, adjusted for age, sex, race, body mass index, height, education, intracranial volume and APOE ɛ4 status.Results: After adjustment, greater volumes of total brain and selected frontal, parietal and temporal areas, and corpus callosum were unidirectionally associated with future faster gait speed over and beyond cross-sectional and autoregressive associations. There were trends towards faster gait speed being associated with future greater hippocampus and precuneus. Higher fitness was unidirectionally associated with future greater parahippocampal gyrus and not with volumes in other areas. Smaller ventricle predicted future higher fitness.Conclusion: Specific regional brain volumes predict future mobility impairment. Impaired mobility is a risk factor for future atrophy of hippocampus and precuneus. Maintaining fitness preserves parahippocampal gyrus volume. Findings provide new insight into the complex and bidirectional relationship between the parallel decline of mobility and cognition often observed in older persons. [ABSTRACT FROM AUTHOR]

The QQ plot is a commonly used technique for informally deciding whether a univariate random sample of size n comes from a specified distribution F. The QQ plot graphs the sample quantiles against the theoretical quantiles of F and then a visual check is made to see whether or not the points are close to a straight line. For a location and scale family of distributions, the intercept and slope of the straight line provide estimates for the shift and scale parameters of the distribution respectively. Here we consider the set Sn of points forming the QQ plot as a random closed set in 2. We show that under certain regularity conditions on the distribution F,Sn converges in probability to a closed, non-random set. In the heavy tailed case where 1 - F is a regularly varying function, a similar result can be shown, but a modification is necessary to provide a statistically sensible result since typically F is not completely known. [ABSTRACT FROM AUTHOR]

Attempts to show that the presumption of unity and disciplinarity--the idea that there is a center or `core' of propositions, procedures, and conclusions or a shared historical `object' of theory and practice--is suggested in the concepts and methods of some schools of economic thought, but is opposed by others. Views that no unified discipline of economics exists; Compares Marxian economic thought and literary theory.

Introduction: Despite a high prevalence of retained bullet fragments (RBFs) after firearm related injury (FRI) there is limited data on the full spectrum of their consequences, particularly the psychological impacts on those injured. Further, the experiences of FRI survivors with RBFs are missing from existing literature. The objective of this study was to explore the psychological impacts of RBFs on individuals who have experienced recent FRI. Methods: Adult (18-65 years) survivors of FRI with radiographically confirmed RBFs were purposively selected from an urban Level 1 trauma center in Atlanta, Georgia, to participate in an in-depth interview. Interviews were conducted between March 2019 and February 2020. Thematic analysis was used to identify a range of psychological effects from RBFs. Results: Interviews from 24 FRI survivors were analyzed: the majority of participants were Black males (N = 22, 92%) with a mean age of 32 years whose FRI occurred ∼8.6 months prior to data collection. The psychological effects of RBFs were grouped into four categories: physical health (eg, pain, limited mobility), emotional well-being (eg, anger, fear), social isolation, and occupational welfare (eg, disability leading to inability to work). A range of coping mechanisms were also identified. Conclusion: Survivors of FRI with RBFs experience a range of psychological impacts that are far-reaching and affect daily activities, mobility, pain and emotional wellbeing. Study results indicate a need for enhanced resources to support those with RBFs. Further, changes to clinical protocols are warranted on removal of RBFs and communication about the effects of leaving RBFs in situ. [ABSTRACT FROM AUTHOR]

The article discusses the result of the study regarding Terson's syndrome in subarachnoid hemorrhage. A man, who was rushed to the emergency department after becoming unconscious, was diagnosed with the presence of Terson's syndrome. The CT scan of his brain revealed subarachnoid hemorrhage with global brain edema. Based on the examination of the radiological findings, there is a noted prominent intraocular hemorrhage illustrated on the CT scan.

Abstract: The Candida antarctica lipase B catalyzed kinetic resolution of (R/S)-1-methoxy-2-propyl-acetate was studied as a model system for the biocatalytic production of chiral secondary alcohols. For this purpose, a kinetic model is proposed involving both enantiomers of this reaction using model discrimination and parameter identification. Starting from a ping–pong bi–bi mechanism, a simplified model with sensitive parameters was derived for the R- and S-enantiomer, respectively. It was validated at pH 7.0, using time-course measurements at varying temperatures (30–60°C) and initial substrate conditions (0.05–1.5M). This model was then used for mechanistic interpretation of the kinetic resolution on a biochemical level. The effect of temperature on kinetic parameters and enantiomeric ratio was investigated and compared to findings from the field of molecular modeling to obtain a better understanding of the reaction system for process design. Values of 21.2 and 9.7kJmol−1 were determined for the enthalpic (Δ R–S ΔH ‡°) and the entropic (–T·Δ R–S ΔS ‡°) contribution of the difference in transition state energy of both enantiomers at 30°C. High enantiomeric ratio''s (E of 47–110) especially at lower temperatures, in addition to enzyme activity at a wide pH range, indicate this biotransformation is a promising example for the industrial production of chiral secondary alcohols. [Copyright &y& Elsevier]

Over the past three decades, considerable effort has been dedicated to quantifying the pace of ageing yet identifying the most essential metrics of ageing remains challenging due to lack of comprehensive measurements and heterogeneity of the ageing processes. Most of the previously proposed metrics of ageing have been emerged from cross-sectional associations with chronological age and predictive accuracy of mortality, thus lacking a conceptual model of functional or phenotypic domains. Further, such models may be biased by selective attrition and are unable to address underlying biological constructs contributing to functional markers of age-related decline. Using longitudinal data from the Baltimore Longitudinal Study of Aging (BLSA), we propose a conceptual framework to identify metrics of ageing that may capture the hierarchical and temporal relationships between functional ageing, phenotypic ageing and biological ageing based on four hypothesized domains: body composition, energy regulation, homeostatic mechanisms and neurodegeneration/neuroplasticity. We explored the longitudinal trajectories of key variables within these phenotypes using linear mixed-effects models and more than 10 years of data. Understanding the longitudinal trajectories across these domains in the BLSA provides a reference for researchers, informs future refinement of the phenotypic ageing framework and establishes a solid foundation for future models of biological ageing. [ABSTRACT FROM AUTHOR]

Although overweight and obesity are associated with poor health outcomes in the elderly, the biological bases of obesity-related behaviors during aging are poorly understood. Common variants in the FTO gene are associated with adiposity in children and younger adults as well as with adverse mental health in older individuals. However, it is unclear whether FTO influences longitudinal trajectories of adiposity and other intermediate phenotypes relevant to mental health during aging. We examined whether a commonly carried obesity-risk variant in the FTO gene (rs1421085 single-nucleotide polymorphism) influences adiposity and is associated with changes in brain function in participants within the Baltimore Longitudinal Study of Aging, one of the longest-running longitudinal aging studies in the United States. Our results show that obesity-related risk allele carriers of FTO gene show dose-dependent increments in body mass index during aging. Moreover, the obesity-related risk allele is associated with reduced medial prefrontal cortical function during aging. Consistent with reduced brain function in regions intrinsic to impulse control and taste responsiveness, risk allele carriers of FTO exhibit dose-dependent increments in both impulsivity and intake of fatty foods. We propose that a common neural mechanism may underlie obesity-associated impulsivity and increased consumption of high-calorie foods during aging. [ABSTRACT FROM AUTHOR]

Background – Evidence is accumulating that patients with polyneuropathy may present with normal clinical deep tendon reflexes (C-DTR). There are few studies that assessed the diagnostic utility of electromyographically recorded DTR (Er-DTR) in patients with polyneuropathy. Objectives – The objectives of this study were twofold: (i) to evaluate the prevalence of preserved C-DTR in polyneuropathy; (ii) diagnostic value of Er-DTR latency measurement in patients with polyneuropathy. Methods – We prospectively studied 38 controls and 185 patients with polyneuropathy. All subjects had evaluation of C-DTR, Er-DTR obtained from right biceps brachii (BR), right patellar (PR) and bilateral ankle reflexes (AR). Results – Of these 185 patients, 118 (63.8%) had chronic axonal neuropathy (CAN), 49 (26.5%) demyelinating polyradiculoneuropathy (DPN) and 18 (9.7%) small fiber neuropathy (SFN). The C-DTR were normal in 65 patients whereas 39 of these 65 (60%) patients had abnormalities of Er-DTR at one or more sites. Er-DTR latencies in patients with polyneuropathies were prolonged at all sites compared with controls ( P < 0.01). Among patients with various types of polyneuropathies the Er-DTR, mean latencies at all the sites and latency indicative of demyelination (>150% of the normal mean) were higher in patients with DPN than that of CAN or SFN ( P < 0.01). Conclusions – We conclude that C-DTR are preserved in 35.1% of the patients with polyneuropathies and Er-DTR should be performed in such patients in order to provide electrophysiological evidence of a polyneuropathy. Er-DTR are useful in distinguishing axonal from demyelinating disorders of peripheral nerve, and detection of subclinical involvement of large fibers in SFN. [ABSTRACT FROM AUTHOR]

The infinite source Poisson model is a fluid queue approximation of network data transmission that assumes that sources begin constant rate transmissions of data at Poisson time points for random lengths of time. This model has been a popular one as analysts attempt to provide explanations for observed features in telecommunications data such as self-similarity, long range dependence and heavy tails. We survey some features of this model in cases where transmission length distributions have (a) tails so heavy that means are infinite, (b) heavy tails with finite mean and infinite variance and (c) finite variance. We survey the self-similarity properties of various descriptor processes in this model and then present analyses of four data sets which show that certain features of the model are consistent with the data while others are contradicted. The data sets are 1) the Boston University 1995 study of web sessions, 2) the UC Berkeley home IP HTTP data collected in November 1996, 3) traces collected in end of 1997 at a Customer Service Switch in Munich, and 4) detailed data from a corporate Ericsson WWW server from October 1998. [ABSTRACT FROM AUTHOR]