Limitations of the Hodgkin-Huxley formalism : effects of single channel kinetics on transmembrane voltage dynamics

A standard membrane model, based on the continuous deterministic Hodgkin-Huxley equations, is compared to an alternative membrane model, based on discrete stochastic ion channel populations represented through Marlcov processes. Simulations explore the relationship between these two levels of description: the behavior predicted by the macroscopic membrane currents versus the behavior predicted by their microscopic ion channels. Discussion considers the extent to which these random events underlying neural signals mediate random events in neural computation

A practical approach to helicopter internal noise prediction

A practical and well correlated procedure for predicting helicopter internal noise is presented. It accounts for the propagation of noise along multiple paths on an octave by octave basis. The method is sufficiently general to be applicable to conventional helicopters as well as other aircraft types, when the appropriate structural geometry, noise source strengths, and material acoustic properties are defined. A guide is provided for the prediction of various helicopter noise sources over a wide range of horsepower for use when measured data are not available. The method is applied to the prediction of the interior levels of the Civil Helicopter Research Aircraft (CHRA), both with and without soundproofing installed. Results include good correlation with measured levels and prediction of the speech interference level within 1.5 db at all conditions. A sample problem is also shown illustrating the use of the procedure. This example calculates the engine casing noise observed in the passenger cabin of the CHRA

Thermodynamic analysis and subscale modeling of space-based orbit transfer vehicle cryogenic propellant resupply

The resupply of the cryogenic propellants is an enabling technology for spacebased orbit transfer vehicles. As part of the NASA Lewis ongoing efforts in microgravity fluid management, thermodynamic analysis and subscale modeling techniques were developed to support an on-orbit test bed for cryogenic fluid management technologies. Analytical results have shown that subscale experimental modeling of liquid resupply can be used to validate analytical models when the appropriate target temperature is selected to relate the model to its prototype system. Further analyses were used to develop a thermodynamic model of the tank chilldown process which is required prior to the no-vent fill operation. These efforts were incorporated into two FORTRAN programs which were used to present preliminary analyticl results

Spherical distance metrics applied to protein structure classification

Observed protein structures usually represent energetically favorable conformations. While not all observed structures are necessarily functional, it is generally agreed that protein structure is closely related to protein function. Given a collection of proteins sharing a common global structure, variations in their local structures at specific, critical locations may result in different biological functions. Structural relationships among proteins are important in the study of the evolution of proteins as well as in drug design and development. Analysis of geometrical 3D protein structure has been shown to be effective with respect to classifying proteins. Prior work has shown that the Double Centroid Reduced Representation (DCRR) model is a useful geometric representation for protein structure with respect to visual models, reducing the quantity of modeled information for each amino acid, yet retaining the most important geometrical and chemical features of each: the centroids of the backbone and of the side-chain. DCRR has not yet been applied in the calculation of geometric structural similarity. Meanwhile, multi-dimensional indexing (MDI) of protein structure combines protein structural analysis with distance metrics to facilitate structural similarity queries and is also used for clustering protein structures into related groups. In this respect, the combination of geometric models with MDI has been shown to be effective. Prior work, notably Distance and Density-based Protein Indexing (DDPIn), applies MDI to protein models based on the geometry of the C-alpha backbone. DDPIn\u27s distance metrics are based on radial and density functions that incorporate spherical-based metrics, and the indices are built from metric-tree (M-tree) structures. This work combines DCRR with DDPIn for the development of new DCRR centroid-based metrics: spherical binning distance and inter-centroid spherical distance. The use of DCRR models will provide additional significant structural information via the inclusion of side-chain centroids. Additionally, the newly developed distance metric functions combined with DCRR and M-tree indexing attempt to improve upon the performance of prior work (DDPIn), given the same data set, with respect to both individual k-nearest neighbor (kNN) search queries as well as clustering all proteins in the index

Ontology of Personhood in Ayurveda from the Perspective of Patients and Physicians in Palampur, Himachal Pradesh: An Independent Study

Scholars in western biomedicine describe the body as a physical entity distinct from mind and soul. However, the human body in Indian systems of medicine integrates the multiple natures of personhood and is both deeply physical and spiritual. This study demonstrates the unique view of personhood, being, health, and illness in Ayurveda through literature research and interviews with practitioners and patients. This study extends past a search for the ontology of personhood in Ayurveda and discusses the implications of this ontology on the way one views oneself and the world around him or her. Through this integrative approach, this study argues that the human body proposed in Ayurveda is fundamentally different from some other traditions of medicine, and because of this difference, the human body is treated differently and health is pursued in a unique manner

Does atomoxetine improve inattentiveness in adults with attention-deficit hyperactivity disorder?

Objective: The objective of this selective EBM review of three composite studies is to determine whether or not atomoxetine improves inattentiveness in adults with attention-deficit hyperactivity disorder (ADHD)? Study Design: A systematic review of three blinded randomized controlled trials (RCTs) published between 2011 and 2021. Data Sources: Research was gathered from PubMed and Embase in December 2020-February 2021 for the three RCTs, and supplemental articles were found in September through November 2021 from PubMed. All three RCTs were published in English and found in peer-reviewed journals and were chosen based on their relevance to the topic question. Outcome Measured: A reduction in inattentiveness while taking atomoxetine vs. placebo. This was measured by the Conners’ Adult ADHD Rating Scale Investigator-Rated/Self-Report Screening Version: Inattention Subscale (CAARS-Inv/S:SV IS)3,5 and Brown Attention-Deficit Disorder Scale (BADDS)4 for Adults before and after P.O. administration of placebo or atomoxetine. The scales range from 0-27 with lower scores indicating milder symptoms and higher scores suggesting greater severity of inattention. Results: In all three RCTs, atomoxetine resulted in a significant reduction in inattentiveness compared to placebo evidenced by symptom scales (p value \u3c 0.001 in Durell et al.3 and Upadhyaya et al.5, and p value \u3c 0.05 in Brown et al.4). Mean changes from baseline inattentiveness scores maintained 4.4 points of difference between atomoxetine and placebo groups in the article by Durell et al.,3 2.2 points in Brown et al.4, and 1.9 points of difference in the RCT by Upadhyaya et al.5 All p-values were statistically significant and all three RCTs had a moderate treatment effect. Conclusions: All three reviewed studies show that atomoxetine resulted in significantly reduced inattentiveness in adults with ADHD. The findings suggest atomoxetine is more effective than placebo for improving focus in the mature ADHD brain. Future studies may cover the recommended treatment duration for atomoxetine in adults, the sufficiency of atomoxetinemonotherapy for the treatment of ADHD in adults, and long-term side effects of chronic atomoxetine use in people aged ≥ 18 years old

The effects of Medicaid and maternal depression on prenatal care and infant health

While in recent years, the infant health production function literature has expanded to incorporate behavioral inputs into the production of infant health current research fails to incorporate the Medicaid-private insurance choice into the mother\u27s decision making process. This dissertation seeks to address this by treating private insurance and Medicaid as endogenous while considering the effects that the Medicaid eligibility rules have on both kinds of coverage. Medicaid and private insurance are entered directly into the health production function so that quality effects may be captured. In addition, a woman\u27s state of mental health is also incorporated into the health production process. Depression may have direct and indirect effects on infant health, as it is a potential negative input into the production process but also a factor that may influence the choice and productivity of other inputs (such as prenatal care). A traditional infant health production model is extended to include the Medicaid-private insurance choice and guides the formulation of the two-stage empirical model. Two reduced form, univariate probits are estimated in the first stage on the Medicaid-private insurance choice. Then, a treatment effects model simultaneously estimates the interaction between prenatal care and birth weight as well as the effects of depression, Medicaid, and private insurance. Finally, utilizing the parameters estimated with my original (1988) data, the effects of expanding Medicaid eligibility according to the 1997 rules are simulated. Additionally, a similar simulation predicts the effect of mechanically treating depressed women or reducing their depressive symptoms (by lowering their CES-D depression score) on the key variables. Results indicate that both depression and Medicaid participation lead to a reduction in birth weight. Prenatal care has no significant effect on birth weight but both smoking and anthropometry do. Simulations reveal that expanding Medicaid eligibility is predicted to improve health outcomes particularly for low-income women and black women. Treating depressed women is also predicted to increase birth weights

Correlation of Environmental Exposure to Polycyclic Aromatic Hydrocarbons and Polymorphisms in the Proto-oncogene v-Rel using Wild Atlantic Menhaden

Hurricane Sandy critically damaged the Atlantic coast of New Jersey in the fall of 2012. This was recorded as the largest storm to hit the Atlantic Ocean, which was manifested by its destruction on the homes and communities of those along the coastline. Contamination of surrounding waters due to this natural disaster was of great interest. The re-suspension of land-based pollution is proposed to make these contaminants more bioavailable to coastal species, such as Atlantic menhaden (Brevoortia tyrannus), which are a crucial biomonitoring species through their ecological and economic uses. A proposed increase of body burdens in Atlantic menhaden could affect human health through toxicity in the aquatic food chain via consumption of other marine species. Atlantic menhaden were caught off the shores of the Atlantic coast surrounding New Jersey and were dissected for their raw fish oil, which was extracted from the oily-natured skin and studied with fluorescence spectroscopy to identify the presence of possible contaminants, such as polycyclic aromatic hydrocarbons (PAHs). Different levels of PAH-like substances were identified in catches from 2011, 2012, and 2013. Genomic analysis was used to study the effects of PAH-like substances on cancer-related genes, specifically proto-oncogene v-Rel (V-Rel Avian Reticuloendotheliosis Viral Oncogene Homolog). The presence of polymorphisms in v-Rel was studied in the previously caught Atlantic menhaden exposed to PAH pollution along the coastline of New Jersey. Analysis of the results indicated that there was no statistical difference in PAH-like compound concentrations or fluorescence patterns of raw fish oils collected before and after Hurricane Sandy. Excitation-Emission Matrix Scanning (EEMS) scans of raw fish oil from catches exposed to high amounts of PAH-like substances showed strong fluorescent signals yet few isomers and high genetic relatedness via gel electrophoresis analysis. EEM scans of raw fish oil with low and decreased fluorescence signals showed prominent bands with extreme variability, resulting in evident polymorphisms. It was found that high PAH concentration samples were associated together with low v-Rel variability and low PAH concentration samples were associated together with high v-Rel variability

Effectiveness of Adult Rehabilitative Mental Health Services in Mental Health Recovery

Adult Rehabilitative Mental Health Services (ARMHS) is a Minnesota based psychiatric rehabilitation program for adults whose ability to function in daily life has been impaired due to the symptoms of mental illness. The goals set and actual outcomes achieved by clients during participation in ARMHS were examined in a secondary data analysis using the CHIME recovery model (Connectedness, Hope, Identity, Meaning in life, and Empowerment) to determine the effectiveness of the program in assisting clients recover from mental illness. Outcomes described were largely mapped to the areas of Connectedness, Meaningful activity, and Empowerment, which may be related to the behavioral orientation of goal development. Overall, the majority of outcomes described successful achievement of goals, supporting ARMHS as an effective service for assisting in recovery from mental illness. Implications for this study are the continued need to use consumer driven measurement tools like CHIME to assess recovery from the perspective of the client rather than assessments driven by the medical model. The improvement of outcome evaluation forms to integrate more accurate ways of measuring the components of recovery would improve the type and quality of data collected during the reassessment process