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Review of Human Coronaviruses and Other Respiratory Viruses and their Neurological Impact on the Central Nervous System
Comprehensive reporting shows that some pathogens, including COVID-19, influenza A and SARS-CoV have sometimes caused pandemics and were linked to more serious diseases and death. A number of respiratory viruses can travel from the respiratory tract to the central nervous system, causing alterations and damage and resulting in long-term neurological diseases.
Heat or Eat? Cold Weather Shocks and Nutrition in Poor American Families
We examine the effects of cold weather periods on family budgets and on nutritional outcomes in poor American families. Expenditures on food and home fuels are tracked by linking the Consumer Expenditure Survey to temperature data. Using the Third National Health and Nutrition Examination Survey, we track calorie consumption, dietary quality, vitamin deficiencies, and anemia in summer and winter months. We find that both rich and poor families increase fuel expenditures in response to unusually cold weather (a 10 degree F drop below normal). At same time, poor families reduce food expenditures by roughly the same amount as the increase in fuel expenditures, while rich families increase food expenditures. Poor adults and children reduce caloric intake by roughly 200 calories during winter months, unlike richer adults and children. In sensitivity analyses, we find that decreases in food expenditure are most pronounced outside the South. We conclude that poor parents and their children outside the South spend and eat less food during cold weather temperature shocks. We surmise that existing social programs fail to buffer against these shocks.
Named entity tagging a very large unbalanced corpus: training and evaluating NE classifiers
We describe a systematic and application-oriented approach to training and evaluating named entity recognition and classification (NERC) systems, the purpose of which is to identify an optimal system and to train an optimal model for named entity tagging DeReKo, a very large general-purpose corpus of contemporary German (Kupietz et al., 2010). DeReKo 's strong dispersion wrt. genre, register and time forces us to base our decision for a specific NERC system on an evaluation performed on a representative sample of DeReKo instead of performance figures that have been reported for the individual NERC systems when evaluated on more uniform and less diverse data. We create and manually annotate such a representative sample as evaluation data for three different NERC systems, for each of which various models are learnt on multiple training data. The proposed sampling method can be viewed as a generally applicable method for sampling evaluation data from an unbalanced target corpus for any sort of natural language processing
Composite vertices that lead to soft form factors
The momentum-space cut-off parameter of hadronic vertex functions
is studied in this paper. We use a composite model where we can measure the
contributions of intermediate particle propagations to . We show that
in many cases a composite vertex function has a much smaller cut-off than its
constituent vertices, particularly when light constituents such as pions are
present in the intermediate state. This suggests that composite
meson-baryon-baryon vertex functions are rather soft, i.e., they have \Lambda
considerably less than 1 GeV. We discuss the origin of this softening of form
factors as well as the implications of our findings on the modeling of nuclear
reactions.Comment: REVTex, 19 pages, 5 figs(to be provided on request
A bistable soft gripper with mechanically embedded sensing and actuation for fast closed-loop grasping
Soft robotic grippers are shown to be high effective for grasping
unstructured objects with simple sensing and control strategies. However, they
are still limited by their speed, sensing capabilities and actuation mechanism.
Hence, their usage have been restricted in highly dynamic grasping tasks. This
paper presents a soft robotic gripper with tunable bistable properties for
sensor-less dynamic grasping. The bistable mechanism allows us to store
arbitrarily large strain energy in the soft system which is then released upon
contact. The mechanism also provides flexibility on the type of actuation
mechanism as the grasping and sensing phase is completely passive. Theoretical
background behind the mechanism is presented with finite element analysis to
provide insights into design parameters. Finally, we experimentally demonstrate
sensor-less dynamic grasping of an unknown object within 0.02 seconds,
including the time to sense and actuate
Structure-Activity Relationships of Synthetic Analogs of Jasmonic Acid and Coronatine on Induction of Benzophenanthridine Alkaloid Accumulation in Eschscholzia californica Cell Cultures
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A facile test system based on the accumulation of benzo[c]phenanthridine alkaloids in Eschscholzia californica cell suspension culture (an indicator of defense gene activation) has been used to analyze a series of synthetic compounds for elicitor-like activity. Of the 200 jasmonic acid and coronatine analogs tested with this system, representative results obtained with 49 of them are presented here. The following can be summarized concerning structure-activity relationships: there is a large degree of plasticity allowed at the C-3 of jasmonic acid in the activation of defense genes. The carbonyl moiety is not strictly required, but exocyclic double bond character appears necessary. The pentenyl side chain at C-2 cannot tolerate bulky groups at the terminal carbon and still be biologically active. Substitutions to the C-1′ position are tolerated if they can potentially undergo β-oxidation. Either an alkanoic acid or methyl ester is required at C-1, or a side chain that can be shortened by β-oxidation or by peptidase hydrolysis. Coronatine and various derivatives thereof are not as effective as jasmonic acid, and derivatives in inducing benzo[c]phenanthridine alkaloid accumulation. Jasmonic acid rather than the octadecanoic precursors is therefore considered to be a likely signal transducer of defense gene activation in planta
A Systematic Review of Existing Clinical Guidelines for the Assessment and Treatment of Tinnitus in Adults
Background: Though clinical guidelines for assessment and treatment of chronic
subjective tinnitus do exist, a comprehensive review of those guidelines has
not been performed. The objective of this review was to identify current
clinical guidelines, and compare their recommendations for the assessment and
treatment of subjective tinnitus in adults. Method: We systematically searched
a range of sources for clinical guidelines (as defined by the Institute of
Medicine, United States) for the assessment and/or treatment of subjective
tinnitus in adults. No restrictions on language or year of publication were
applied to guidelines. Results: Clinical guidelines from Denmark, Germany,
Sweden, The Netherlands, and the United States were included in the review.
There was a high level of consistency across the guidelines with regard to
recommendations for audiometric assessment, physical examination, use of a
validated questionnaire(s) to assess tinnitus related distress, and referral
to a psychologist when required. Cognitive behavioral treatment for tinnitus
related distress, use of hearing aids in instances of hearing loss and
recommendations against the use of medicines were consistent across the
included guidelines. Differences between the guidelines centered on the use of
imaging in assessment procedures and sound therapy as a form of treatment for
tinnitus distress respectively. Conclusion: Given the level of commonality
across tinnitus guidelines from different countries the development of a
European guideline for the assessment and treatment of subjective tinnitus in
adults seems feasible. This guideline would have the potential to benefit the
large number of clinicians in countries where clinical guidelines do not yet
exist, and would support standardization of treatment for patients across
Europe
Identification of new members of the Escherichia coli K-12 MG1655 SlyA regulon.
SlyA is a member of the MarR family of bacterial transcriptional regulators. Previously, SlyA has been shown to directly regulate only two operons in Escherichia coli K-12 MG1655, fimB and hlyE (clyA). In both cases SlyA activates gene expression by antagonizing repression by the nucleoid associated protein H-NS. Here the transcript profiles of aerobic glucose-limited steady-state chemostat cultures of E. coli K-12 MG1655, slyA mutant and slyA over-expression strains are reported. The transcript profile of the slyA mutant was not significantly different to that of the parent; however, that of the slyA expression strain was significantly different from that of the vector control. Transcripts representing 27 operons were increased in abundance, whereas 3 were decreased. Of the 30 differentially regulated operons, 24 have been previously associated with sites of H-NS binding, suggesting that antagonism of H-NS repression is a common feature of SlyA-mediated transcription regulation. Direct binding of SlyA to DNA located upstream of a selection of these targets permitted the identification of new operons likely to be directly regulated by SlyA. Transcripts of four operons coding for cryptic adhesins exhibited enhanced expression and this was consistent with enhanced biofilm formation associated with the SlyA over-producing strain
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