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Roles of estrogen receptor-alpha in mediating life span: the hypothalamic deregulation hypothesis.
In several species caloric restriction (CR) extends life span. In this paper we integrate data from studies on CR and other sources to articulate the hypothalamic deregulation hypothesis by which estrogen receptor-alpha (ER-α) signaling in the hypothalamus and limbic system affects life span under the stress of CR in mammals. ER-α is one of two principal estrogen-binding receptors differentially expressed in the amygdala, hippocampus, and several key hypothalamic nuclei: the arcuate nucleus (ARN), preoptic area (POA), ventromedial nucleus (VMN), antero ventral periventricular nucleus (AVPV), paraventricular nucleus (PVN), supraoptic nucleus (SON), and suprachiasmatic nucleus (SCN). Estradiol signaling via ER-α is essential in basal level functioning of reproductive cycle, sexually receptive behaviors, physiological stress responses, as well as sleep cycle, and other nonsexual behaviors. When an organism is placed under long-term CR, which introduces an external stress to this ER-α signaling, the reduction of ER-α expression is attenuated over time in the hypothalamus. This review paper seeks to characterize the downstream effects of ER-α in the hypothalamus and limbic system that affect normal endocrine functioning
Uji Aktivitas Antibakteri Ekstrak Etanol Daun Jarak Pagar (Jatropha Curcas L) Terhadap Bakteri Staphylococcus Aureus Atcc 25923, Escherichia Coli Atcc 25922, Dan Salmonella Typhi Atcc 1408
Jatropha curcas L is a plant species that can be used for curing, since it contains flavonoid, saponin, and tanin. Jatropha multifida L is proved to have antibacterial activities (Sisunandar, et.al., 2002). This research was intended to find out the antibacterial activities of ethanol extracts of Jatropha curcas L leaves on bacteria Staphylococus aureus, Escherichia coli, and Salmonella typhi, find out the effectiveness of those antibacterial activities and identify the compound groups contained in the ethanol extracts, the result of antibacterial activity of ethanol extracts of Jatropha curcas L was analized by statistic. Employing a maceration method, Jatropha curcas L leaves were extracted using ethanol 70% for five days. Employing an agar-diffusion method aided by disk papers and in order to find out the inhibitory area diameters of the extracts, the extracts were then tested for their antibacterial activities. Qualitative analysis on the chemical contents of the extracts were conducted employing. TLC method aided by silica-gel stationary phases for saponin and tanin and cellulose phases for flavonoid. The motion phases used ethyl acetat-acidformiat-acid acetat-water for flavonoid, chloroform-methanol for saponin and buthanol-acid acetat-water for tanin. The result of the test on antibacterial activities were analyzed statistically using Kruskall Wallis and Mann & Whitney tests. The analysis showed that ethanol extracts of the Jatropha curcas L leaves inhibited the growth of Staphylococcus aureus but not the growth of Eschericia coli and Salmonella typhi. The testing concentrations of 20%, 40%, 60%, 80%, and 100% b/v produed inhibitory area diameters averaging 8.25, 9.25, 11.00, 13.25, and 19.00 mm respectively. The positive control of Ampicillin produced an average inhibitory area diameters of 40.00 mm while the solvent control did not produce any inhibitory area diameters. Statistical test showed that there were significant differences among the different concentrations of the extracts.Thin Layer Chromatography tests produced yellow color showing the existence of flavonoid, bluish violet color showing the existence of saponin, and grayish green color showing the existence of tanin
Experimental Validation of a Numerical Forward Model for Tunnel Detection Using Cross-Borehole Radar
The goal of this research is to develop an experimentally validated twodimensional (2D) finite difference frequency domain (FDFD) numerical forward model to study the potential of radar-based tunnel detection. Tunnel detection has become a subject of interest to the nation due to the use of tunnels by illegal immigrants, smugglers, prisoners, assailants, and terrorists. These concerns call for research to nondestructively detect, localize, and monitor tunnels. Nondestructive detection requires robust image reconstruction and inverse models, which in turn need robust forward models. Cross-Well Radar (CWR) modality is used for experimentation to avoid soil-air interface roughness. CWR is not a versatile field technology for political boundaries but is still applicable to monitoring the perimeter of buildings or secure sites. Multiple-depth wideband frequency-response measurements are experimentally collected in fully water-saturated sand, across PVC-cased ferrite-bead-jacketed borehole monopole antennae at a pilot scale facility (referred to as SoilBED). The experimental results are then compared with the 2D-FDFD model. The agreement between the results of the numerical and experimental simulations is then evaluated. Results of this work provide key diagnostic tools that can help to develop the algorithms needed for the detection of underground tunnels using radar-based methods
Interprofessional Education: Theoretical and Practical Considerations for Occupational Therapy Educators
Interprofessional education (IPE) is an integral part of occupational therapy education as programs across the United States incorporate IPE into existing courses and develop new, innovative curricula. The American Occupational Therapy Association (AOTA) Commission on Education (COE) proposed in its 2015 position paper on IPE in occupational therapy curricula, that IPE is imperative for effective and ethical practice in today’s healthcare environment. Through participation in a Scholarship of Teaching and Learning program focusing on IPE, the authors examined broad constructs and practical implementation of IPE in occupational therapy education. As occupational therapy educators explore opportunities to collaborate with a diverse range of professions, this article provides information about key conceptual frameworks, approaches for faculty training and development, and methods for evaluating IPE outcomes
An Interprofessional Education Nursing Home Dining Simulation Promotes Changes in Student Attitudes
INTRODUCTION The purpose of this study was to assess changes in attitudes toward interprofessional collaborative competency attainment of undergraduate dietetics, gerontology/long term care administration, and occupational therapy assistant (OTA) students as a result of participating in a problem-based simulated nursing home dining experience.
METHODS A one-group quasi-experimental post-test design, with convenience sample, was used in this study. Forty-three students completed the Interprofessional Collaborative Competencies Attainment Survey (ICCAS) tool, a validated 20-item scale measuring attitudes toward interprofessional collaborative competency attainment. The ICCAS assesses six competencies: communication, collaboration, roles and responsibilities, collaborative patient/familycentered approach, conflict management/resolution and team functioning. A paired-sample t-test was conducted to evaluate the impact of the dining simulation on students’ ICCAS responses.
RESULTS A statistically significant increase was found in the ICCAS summative score from the retrospective look designated as Time 1 (M=108.95; SD=19.76) to Time 2 [M=127.65; SD=17.86, t(42)= -8.63, p\u3c.0005].
CONCLUSION The results of this study have potential implications for educators, practitioners and researchers. Careful planning during case development enhanced the realism and accuracy of the simulation. This nursing home dining simulation using problem-based case scenarios was found to be an effective method of promoting interprofessional collaborative competencies with a unique group of healthcare students
On the Dynamics of Bianchi IX cosmological models
A cosmological description of the universe is proposed in the context of
Hamiltonian formulation of a Bianchi IX cosmology minimally coupled to a
massless scalar field. The classical and quantum results are studied with
special attention to the case of closed Friedmann-Robertson-Walker model.Comment: 11 pages, 1 figur
Control of the edge plasma modes by hot limiter biasing in the IR-T1 tokamak
Tokamak plasma modes were analyzed using the Fast Fourier Transform (FFT) in presence of hot limiter biasing system in the IR-T1 Tokamak. Fourier analysis is reliable technique for mode detection in tokamaks. For this purpose we used a poloidal array of Mirnov coils and hot limiter biasing system. After Fourier analysis of Mirnov coils data in presence of hot biased limiter, Power Spectral Density (PSD) diagram was plotted. PSD describes how the power of a signal is distributed with frequency. In this contribution we also determined edge safety factor and safety factor from Fourier based derived mode numbers q = m/n. We obtained the maximum MHD activity using power spectrum at the frequency 33 kHz. Also the edge safety factor was determined less than 3, and the values of obtained safety factor from the mode numbers are between 2 ≤ q ≤ 5. Results show that hot limiter biasing can be used for increasing the plasma safety factor.Моды плазмы токамака анализировались с использованием быстрого преобразования Фурье (БПФ) при наличии системы подачи напряжения на горячий лимитер в токамаке IR-T1. Использовалась полоидальная схема расположения катушек Мирнова. С помощью Фурье-анализа данных катушек Мирнова была построена диаграмма спектральной плотности мощности (СПМ), описывающая распределение мощности сигнала с частотой. Были определены величины q на краю плазмы и по данным Фурье-анализа (как отношение мод: q=m/n). Максимум активности МГД оказался на частоте 33 кГц; на краю величина q≤ 3, а найденная из номеров гармоник − 2 ≤ q ≤ 5. Результаты показали, что подача напряжения на лимитер может использоваться для увеличения плазменного коэффициента надежности.Моди плазми токамака аналізувалися з використанням швидкого перетворення Фур'є (ШПФ) за наявності системи подачі напруги на гарячий лімітер у токамаці IR-T1. Використовувалась полоїдальна схема розміщення котушок Мірнова. За допомогою Фур'є-аналізу даних з котушок Мірнова була побудована діаграма спектральної щільності потужності (СЩП), яка описує розподіл потужності сигналу з частотою. Були визначені величини q на краю плазми і по даним Фур'є-аналізу (як відношення мод: q = m/n). Максимум активності МГД виявився на частоті 33 кГц; на краю величина q ≤ 3, а знайдена з номерів гармонік – 2 ≤ q ≤ 5. Результати показали, що подача напруги на лімітер може використовуватися для збільшення плазмового коефіцієнта надійності
Reduction of disc brake squeal noise using constrained layer dampers
Brakes squeal has remained to be one of the major Noise, Vibration and Harshness (NSH) challenges in brake system design and development. It has been a concern for automotive industry for decade. Brake researchers have proposed many brake squeal reduction and prevention methods in order to overcome and reduce the squeal that emanates from the brake disc systems. In this paper, the effectiveness of constrained layer dampers (CLD) in reducing disc brake squeal noise was investigated. CLD isolates the brake squeal noise through shear deformations of the viscoelastic materials. Two sets of brake tests were conducted using the brake test dynamometer with the application of CLD. Two different types of CLD were used which are three-layer constrained layer damper and four-layer constrained layer damper. Squeal tests were carried out using brake noise test rig based on the global standard procedure SAE J2521. From the test, four-layer CLD configuration works more efficient than three-layer CLD configuration. CLD made up of nitrile butadiene rubber, silicone rubber and mild steel proved to be the most effective noise insulator at hydraulic pressure range of 5 bar to 30 bar and temperature range of 50oC to 200oC with a maximum noise reduction of 11.3 dBA. Thus, CLD technique was proven to be an effective method in reducing brake squeal noise
Planet Hunters X: Searching for Nearby Neighbors of 75 Planet and Eclipsing Binary Candidates from the K2 Kepler Extended Mission
We present high-resolution observations of a sample of 75 K2 targets from
Campaigns 1-3 using speckle interferometry on the Southern Astrophysical
Research (SOAR) telescope and adaptive optics (AO) imaging at the Keck II
telescope. The median SOAR -band and Keck -band detection limits at 1"
were ~mag and ~mag, respectively. This
sample includes 37 stars likely to host planets, 32 targets likely to be
eclipsing binaries (EBs), and 6 other targets previously labeled as likely
planetary false positives. We find nine likely physically bound companion stars
within 3" of three candidate transiting exoplanet host stars and six likely
EBs. Six of the nine detected companions are new discoveries; one of the six,
EPIC 206061524, is associated with a planet candidate. Among the EB candidates,
companions were only found near the shortest period ones ( days), which is
in line with previous results showing high multiplicity near short-period
binary stars. This high-resolution data, including both the detected companions
and the limits on potential unseen companions, will be useful in future planet
vetting and stellar multiplicity rate studies for planets and binaries.Comment: Accepted in A
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