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Social Factors that Exacerbate Features of Borderline Personality Disorder in Young Adult Women Between 25 and 35 years of age Living in the Commonwealth of Puerto Rico
The high prevalence of BPD hospitalizations, unsuccessful treatments, poor social awareness, suicide attempts and complete suicides were motivating forces for this research study. The aim was to uncover pertinent social factors that exacerbate BPD in the lives of individuals with this affliction and therefore find ways to combat this disease. Since most of the individuals affected by this disease are female, the present research was focused on uncovering factors that increased the likelihood of BPD factors in women between the ages of 25-35 years. Borderline personality disorder is often viewed as difficult to treat. However, recent research shows that BPD can be treated effectively; therefore many people with this condition improve over time (Zanarini, Frankenburg, Hennen, Reich, & Silk, 2005). The findings of this study provide insight into this mental health problem and may potentially serve as useful literature for mental health clinicians at the forefront of this poorly understood disorder
Space Station Freedom environmental control and life support system phase 3 simplified integrated test detailed report
A description of the phase 3 simplified integrated test (SIT) conducted at the Marshall Space Flight Center (MSFC) Core Module Integration Facility (CMIF) in 1989 is presented. This was the first test in the phase 3 series integrated environmental control and life support systems (ECLSS) tests. The basic goal of the SIT was to achieve full integration of the baseline air revitalization (AR) subsystems for Space Station Freedom. Included is a description of the SIT configuration, a performance analysis of each subsystem, results from air and water sampling, and a discussion of lessons learned from the test. Also included is a full description of the preprototype ECLSS hardware used in the test
Trade Spaces in Crewed Spacecraft Atmosphere Revitalization System Development
Developing the technological response to realizing an efficient atmosphere revitalization system for future crewed spacecraft and space habitats requires identifying and describing functional trade spaces. Mission concepts and requirements dictate the necessary functions; however, the combination and sequence of those functions possess significant flexibility. Us-ing a closed loop environmental control and life support (ECLS) system architecture as a starting basis, a functional unit operations approach is developed to identify trade spaces. Generalized technological responses to each trade space are discussed. Key performance parameters that apply to functional areas are described
Space Station CMIF extended duration metabolic control test
The Space Station Extended Duration Metabolic Control Test (EMCT) was conducted at the MSFC Core Module Integration Facility. The primary objective of the EMCT was to gather performance data from a partially-closed regenerative Environmental Control and Life Support (ECLS) system functioning under steady-state conditions. Included is a description of the EMCT configuration, a summary of events, a discussion of anomalies that occurred during the test, and detailed results and analysis from individual measurements of water and gas samples taken during the test. A comparison of the physical, chemical, and microbiological methods used in the post test laboratory analyses of the water samples is included. The preprototype ECLS hardware used in the test, providing an overall process description and theory of operation for each hardware item. Analytical results pertaining to a system level mass balance and selected system power estimates are also included
National Aeronautics and Space Administration (NASA) Environmental Control and Life Support (ECLS) Capability Roadmap Development for Exploration
NASA is considering a number of future human space exploration mission concepts. Although detailed requirements and vehicle architectures remain mostly undefined, near-term technology investment decisions need to be guided by the anticipated capabilities needed to enable or enhance the mission concepts. This paper describes a roadmap that NASA has formulated to guide the development of Environmental Control and Life Support Systems (ECLSS) capabilities required to enhance the long-term operation of the International Space Station (ISS) and enable beyond-Low Earth Orbit (LEO) human exploration missions. Three generic mission types were defined to serve as a basis for developing a prioritized list of needed capabilities and technologies. Those are 1) a short duration micro gravity mission; 2) a long duration transit microgravity mission; and 3) a long duration surface exploration mission. To organize the effort, ECLSS was categorized into three major functional groups (atmosphere, water, and solid waste management) with each broken down into sub-functions. The ability of existing, flight-proven state-of-the-art (SOA) technologies to meet the functional needs of each of the three mission types was then assessed. When SOA capabilities fell short of meeting the needs, those "gaps" were prioritized in terms of whether or not the corresponding capabilities enable or enhance each of the mission types. The resulting list of enabling and enhancing capability gaps can be used to guide future ECLSS development. A strategy to fulfill those needs over time was then developed in the form of a roadmap. Through execution of this roadmap, the hardware and technologies needed to enable and enhance exploration may be developed in a manner that synergistically benefits the ISS operational capability, supports Multi-Purpose Crew Vehicle (MPCV) development, and sustains long-term technology investments for longer duration missions. This paper summarizes NASA s ECLSS capability roadmap development process, findings, and recommendatio
Rectifying junctions of tin oxide and poly(3-hexylthiophene) nanofibers fabricated via electrospinning
Abstract: A fast, simple, and inexpensive method to fabricate in air, p-n diodes using electrospun tin oxide nanoribbons and regioregular poly(3-hexylthiophene) nanofibers is described. In addition to being a rectifier under ambient illumination or in the dark, the advantage of our design is the complete exposure of the rectifying nanojunction to the surrounding environment, making them attractive candidates in the potential fabrication of low power consumption diodes and sensors. The diode characteristics were analyzed using the standard diode equation and its use as a UV light sensor was examined
Intracellular FGF14 (iFGF14) is required for spontaneous and evoked firing in cerebellar Purkinje neurons and for motor coordination and balance
Mutations in FGF14, which encodes intracellular fibroblast growth factor 14 (iFGF14), have been linked to spinocerebellar ataxia (SCA27). In addition, mice lacking Fgf14 (Fgf14(ā/ā)) exhibit an ataxia phenotype resembling SCA27, accompanied by marked changes in the excitability of cerebellar granule and Purkinje neurons. It is not known, however, whether these phenotypes result from defects in neuronal development or if they reflect a physiological requirement for iFGF14 in the adult cerebellum. Here, we demonstrate that the acute and selective Fgf14-targeted short hairpin RNA (shRNA)-mediated in vivo āknock-downā of iFGF14 in adult Purkinje neurons attenuates spontaneous and evoked action potential firing without measurably affecting the expression or localization of voltage-gated Na(+) (Nav) channels at Purkinje neuron axon initial segments. The selective shRNA-mediated in vivo āknock-downā of iFGF14 in adult Purkinje neurons also impairs motor coordination and balance. Repetitive firing can be restored in Fgf14-targeted shRNA-expressing Purkinje neurons, as well as in Fgf14(ā/ā) Purkinje neurons, by prior membrane hyperpolarization, suggesting that the iFGF14-mediated regulation of the excitability of mature Purkinje neurons depends on membrane potential. Further experiments revealed that the loss of iFGF14 results in a marked hyperpolarizing shift in the voltage dependence of steady-state inactivation of the Nav currents in adult Purkinje neurons. We also show here that expressing iFGF14 selectively in adult Fgf14(ā/ā) Purkinje neurons rescues spontaneous firing and improves motor performance. Together, these results demonstrate that iFGF14 is required for spontaneous and evoked action potential firing in adult Purkinje neurons, thereby controlling the output of these cells and the regulation of motor coordination and balance
The sodium channel accessory subunit NavĪ²1 regulates neuronal excitability through modulation of repolarizing voltage-gated K+ channels
The channel pore-forming Ī± subunit Kv4.2 is a major constituent of A-type (I(A)) potassium currents and a key regulator of neuronal membrane excitability. Multiple mechanisms regulate the properties, subcellular targeting and cell surface expression of Kv4.2-encoded channels. In the present study, shotgun proteomic analyses of immunoprecipitated mouse brain Kv4.2 channel complexes unexpectedly identified the voltage-gated Na(+) channel accessory subunit NavĪ²1. Voltage-clamp and current-clamp recordings revealed that knockdown of NavĪ²1 decreases I(A) densities in isolated cortical neurons and that action potential waveforms are prolonged and repetitive firing is increased in Scn1b null cortical pyramidal neurons lacking NavĪ²1. Biochemical and voltage-clamp experiments further demonstrated that NavĪ²1 interacts with and increases the stability of heterologously expressed Kv4.2 protein, resulting in greater total and cell surface Kv4.2 protein expression and in larger Kv4.2-encoded current densities. Taken together, the results presented here identify NavĪ²1 as a component of native neuronal Kv4.2-encoded I(A) channel complexes and a novel regulator of I(A) channel densities and neuronal excitability
"It's making contacts" : notions of social capital and implications for widening access to medical education
Acknowledgements Our thanks to the Medical Schools Council (MSC) of the UK for funding Study A; REACH Scotland for funding Study B; and Queen Mary University of London, and to the medical school applicants and students who gave their time to be interviewed. Our thanks also to Dr Sean Zhou and Dr Sally Curtis, and Manjul Medhi, for their help with data collection for studies A and B respectively. Our thanks also to Dr Lara Varpio, Uniformed Services University of the USA, for her advice and guidance on collating data sets and her comments on the draft manuscript.Peer reviewedPublisher PD
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