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Light-Scattering and Ellipsometry Studies of the Two-Dimensional Smectic-C to Smectic-A Transition in Thin Liquid-Crystal Films
Ellipsometry and light-scattering measurements are presented for the critical region near the two-dimensional XY-like smectic-C to smectic-A phase transition in thin, freely suspended films of the liquid crystal p-decyloxybenzylidene p-aminocinnamaic acid 2-methylbutyl ester. The macro-scopically observed smectic-C tilt order parameter was found to obey a scaling relation as a function of temperature and film thickness, indicating that only the surface layers order over a wide range of temperatures. Deep within the smectic-C phase, the tilt order parameters for all thickness films measured converged upon a unique value at which the smectic-C to smectic-I transition took place. The light-scattering intensities and decay times above the smectic-C to smectic-A transition were found to scale with the Kosterlitz-Thouless correlation length, as predicted by dynamical theories of the transition. Measurements of the predicted Nelson-Kosterlitz universal jump in concurred with estimates for the bulk material parameters and with the light-scattering results.Engineering and Applied Science
Development of Smart Meter to Monitor Real Time Energy Consumption for Sustainability
This study constructed a Smart Energy Meter where energy consumption can be viewed by the consumers based on rreal time using data from smart meters. Its goals are to increase productivity, make readings more precise, and take less time to determine an individual residence's energy consumption. The device is made up of the PZEM-016 AC Energy Meter, RS-485 UART Serial Converter, NodeMCU ESP8266, Blynk IoT Application, Arduino Uno R3, and LCD Arduino Keypad Module Shield Board. The PZEM-016 is used in this smart energy meter to measure voltage, current, power, frequency, power factor, and energy consumption. Because it lacks its own display, an RS-485 was utilized to communicate with the NodeMCU and Arduino Uno. The NodeMCU sends the parameters to Blynk IoT App as long as it is connected to a fixed mobile WiFi. The Blynk will then display a real-time measurement of the parameters. The Arduino Uno is programmed to display the parameters to the LCD Keypad Module. The device was tested in an actual household. The researchers conducted 48-hour observation on the household where the energy displayed in the Blynk IoT App and the LCD display matches at approximately 9 kWh which is the same as the actual energy meter of the house that is 9kWh. The device is also tested on different appliances which resulted in the same energy consumption in both the Blynk IoT App and LCD display with the ratings of the appliances. The device was found functional
Review on possible gravitational anomalies
This is an updated introductory review of 2 possible gravitational anomalies
that has attracted part of the Scientific community: the Allais effect that
occur during solar eclipses, and the Pioneer 10 spacecraft anomaly,
experimented also by Pioneer 11 and Ulysses spacecrafts. It seems that, to
date, no satisfactory conventional explanation exist to these phenomena, and
this suggests that possible new physics will be needed to account for them. The
main purpose of this review is to announce 3 other new measurements that will
be carried on during the 2005 solar eclipses in Panama and Colombia (Apr. 8)
and in Portugal (Oct.15).Comment: Published in 'Journal of Physics: Conferences Series of the American
Institute of Physics'. Contribution for the VI Mexican School on Gravitation
and Mathematical Physics "Approaches to Quantum Gravity" (Playa del Carmen,
Quintana Roo, Mexico, Nov. 21-27, 2004). Updates to this information will be
posted in http://www.lsc-group.phys.uwm.edu/~xavier.amador/anomalies.htm
Anharmonic phonon decay in cubic GaN
We present a Raman scattering study of optical phonons in zincblende (cubic) GaN for temperatures ranging from 80 to 750 K. The experiments were performed on high quality, cubic GaN films grown by molecular beamepitaxy on GaAs (001) substrates. The observed temperature dependence of the optical phonon frequencies and linewidths is analyzed in the framework of anharmonic decay theory, and possible decay channels are discussed in the light of density-functional theory calculations. The LO mode relaxation is found to occur via asymmetric decay into acoustic phonons, with an appreciable contribution of higher order processes. The TO mode linewidth shows a weak temperature dependence and its frequency downshift is primarily determined by the lattice thermal expansion. The LO phonon lifetime is derived from the observed Raman linewidth and an excellent agreement with previous theoretical predictions is foun
Genome-by-Trauma Exposure Interactions in Adults With Depression in the UK Biobank
IMPORTANCE: Self-reported trauma exposure has consistently been found to be a risk factor for major depressive disorder (MDD), and several studies have reported interactions with genetic liability. To date, most studies have examined gene-environment interactions with trauma exposure using genome-wide variants (single-nucleotide variations [SNVs]) or polygenic scores, both typically capturing less than 3% of phenotypic risk variance. OBJECTIVE: To reexamine genome-by-trauma interaction associations using genetic measures using all available genotyped data and thus, maximizing accounted variance. DESIGN, SETTING, AND PARTICIPANTS: The UK Biobank study was conducted from April 2007 to May 1, 2016 (follow-up mental health questionnaire). The current study used available cross-sectional genomic and trauma exposure data from UK Biobank. Participants who completed the mental health questionnaire and had available genetic, trauma experience, depressive symptoms, and/or neuroticism information were included. Data were analyzed from April 1 to August 30, 2021. EXPOSURES: Trauma and genome-by-trauma exposure interactions. MAIN OUTCOMES AND MEASURES: Measures of self-reported depression, neuroticism, and trauma exposure with whole-genome SNV data are available from the UK Biobank study. Here, a mixed-model statistical approach using genetic, trauma exposure, and genome-by-trauma exposure interaction similarity matrices was used to explore sources of variation in depression and neuroticism. RESULTS: Analyses were conducted on 148 129 participants (mean [SD] age, 56 [7] years) of which 76 995 were female (52.0%). The study approach estimated the heritability (SE) of MDD to be approximately 0.160 (0.016). Subtypes of self-reported trauma exposure (catastrophic, adult, childhood, and full trauma) accounted for a significant proportion of the variance of MDD, with heritability (SE) ranging from 0.056 (0.013) to 0.176 (0.025). The proportion of MDD risk variance accounted for by significant genome-by-trauma interaction revealed estimates (SD) ranging from 0.074 (0.006) to 0.201 (0.009). Results from sex-specific analyses found genome-by-trauma interaction variance estimates approximately 5-fold greater for MDD in male participants (0.441 [0.018]) than in female participants (0.086 [0.009]). CONCLUSIONS AND RELEVANCE: This cross-sectional study used an approach combining all genome-wide SNV data when exploring genome-by-trauma interactions in individuals with MDD; findings suggest that such interactions were associated with depression manifestation. Genome-by-trauma interaction accounts for greater trait variance in male individuals, which points to potential differences in depression etiology between the sexes. The methodology used in this study can be extrapolated to other environmental factors to identify modifiable risk environments and at-risk groups to target with interventions
The Shape of Gravity in a Warped Deformed Conifold
We study the spectrum of the gravitational modes in Minkowski spacetime due
to a 6-dimensional warped deformed conifold, i.e., a warped throat, in
superstring theory. After identifying the zero mode as the usual 4D graviton,
we present the KK spectrum as well as other excitation modes. Gluing the throat
to the bulk (a realistic scenario), we see that the graviton has a rather
uniform probability distribution everywhere while a KK mode is peaked in the
throat, as expected. Due to the suppressed measure of the throat in the wave
function normalization, we find that a KK mode's probability in the bulk can be
comparable to that of the graviton mode. We also present the tunneling
probabilities of a KK mode from the inflationary throat to the bulk and to
another throat. Due to resonance effect, the latter may not be suppressed as
natively expected. Implication of this property to reheating after brane
inflation is discussed
Caracterização morfológica de Jatropha mollissima (Pohl) Baill.
O gênero Jatropha tem ganhado espaço na cena agrária, visto o grande potencial sugerido a espécie Jatropha curcas L. , conhecida como pinhão manso. Contudo, cada vez mais tem-se buscado compreender espécies circumvizinhas da espécies em questão, em busca de melhorar a compreensão e obter mais informações para o melhoramento de culturas. Jatropha mollissima (Pohl) Baill., ou pinhão bravo, a muito vem sido investigada, não apenas por sua proximidade com o pinhão manso, mas também por ser uma espécie utilizada medicinalmente à séculos, difundido através de tradição cultural empírica. A caracterização morfológica detalhada de espécies contribuem para compreensão desta como um todo, além de descrever caracteres que podem ser utilizados no melhoramento genético, assim, neste trabalho, visou-se uma caracterização descritiva detalhada da espécie J. mollissima
A biophysical model of prokaryotic diversity in geothermal hot springs
Recent field investigations of photosynthetic bacteria living in geothermal
hot spring environments have revealed surprisingly complex ecosystems, with an
unexpected level of genetic diversity. One case of particular interest involves
the distribution along hot spring thermal gradients of genetically distinct
bacterial strains that differ in their preferred temperatures for reproduction
and photosynthesis. In such systems, a single variable, temperature, defines
the relevant environmental variation. In spite of this, each region along the
thermal gradient exhibits multiple strains of photosynthetic bacteria adapted
to several distinct thermal optima, rather than the expected single thermal
strain adapted to the local environmental temperature. Here we analyze
microbiology data from several ecological studies to show that the thermal
distribution field data exhibit several universal features independent of
location and specific bacterial strain. These include the distribution of
optimal temperatures of different thermal strains and the functional dependence
of the net population density on temperature. Further, we present a simple
population dynamics model of these systems that is highly constrained by
biophysical data and by physical features of the environment. This model can
explain in detail the observed diversity of different strains of the
photosynthetic bacteria. It also reproduces the observed thermal population
distributions, as well as certain features of population dynamics observed in
laboratory studies of the same organisms
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