4,501 research outputs found
Production of nanodrug for Bacillus cereus isolated from HIV positive patient using Mallotus philippensis
AbstractThe present investigation was aimed to synthesis of silver nanoparticles (AgNPs) using Mallotus philippensis leaf extract and their antibacterial potential against Bacillus cereus isolated from HIV positive patient. In this, UV- Visible spectroscopy showed the high peak of absorption band at 450Â nm. Based on XRD analysis, face centered cubic structure and average size of the AgNPs was around 16Â nm. FTIR spectroscopy study revealed the seventeen functional groups of the AgNPs was observed. The morphology of AgNPs was spherical, oval shapes and diameter of the particle size ranges between 9 and 24Â nm was measured using transmission electron microscopy (TEM). In addition to these green synthesized AgNPs were found to express the higher efficacy in inhibiting the growth of Bacillus cereus (B. cereus) isolated from the HIV-positive patient
Spectroscopic investigations, DFT computations and other molecular properties of 2,4-dimethylbenzoic acid
The molecular vibrations of 2,4-dimethylbenzoicacid (DMBA) have been investigated by recording Fourier transform infrared (FTIR) and FT-Raman spectroscopy. The complete vibrational assignment and analysis of the fundamental modes of the compound have been carried out using the experimental data and quantum chemical studies from DFT calculations employing MPW1PW91 and B3LYP methods employing 6-311++G(d,p) basis set. The 1H and 13C NMR chemical shifts have been calculated with the GIAO method using the optimized parameters obtained from B3LYP/6-311+G(d,p) method. Important thermodynamic properties and electronic properties have been calculated. Low value of HOMO-LUMO energy gap suggests the possibility of intramolecular charge transfer in the molecule. Furthermore, the first hyperpolarizability and total dipole moment of the molecule have been calculated
The Gaseous Extent of Galaxies and the Origin of \lya Absorption Systems. III. Hubble Space Telescope Imaging of \lya-Absorbing Galaxies at z < 1
We present initial results of a program to obtain and analyze HST WFPC2
images of galaxies identified in an imaging and spectroscopic survey of faint
galaxies in fields of HST spectroscopic target QSOs. We measure properties of
87 galaxies, of which 33 are associated with corresponding \lya absorption
systems and 24 do not produce corresponding \lya absorption lines to within
sensitive upper limits. Considering only galaxy and absorber pairs that are
likely to be physically associated and excluding galaxy and absorber pairs
within 3000 \kms of the background QSOs leaves 26 galaxy and absorber pairs and
seven galaxies that do not produce corresponding \lya absorption lines to
within sensitive upper limits. Redshifts of the galaxy and absorber pairs range
from 0.0750 to 0.8912 with a median of 0.3718, and impact parameter separations
of the galaxy and absorber pairs range from 12.4 to kpc with a
median of kpc. The primary result of the analysis is that the
amount of gas encountered along the line of sight depends on the galaxy impact
parameter and B-band luminosity but does not depend strongly on the galaxy
average surface brightness, disk-to-bulge ratio, or redshift. This result
confirms and improves upon the anti-correlation between \lya absorption
equivalent width and galaxy impact parameter found previously by Lanzetta et
al. (1995). There is no evidence that galaxy interactions play an important
role in distributing tenuous gas around galaxies in most cases. Galaxies might
account for all \lya absorption systems with \AA, but this depends on
the unknown luminosity function and gaseous cross sections of low-luminosity
galaxies as well as on the uncertainties of the observed number density of \lya
absorption systems.Comment: Minor changes. Figure 1 stays intact and is available at
ftp://ftp.ess.sunysb.edu/pub/lanzetta/wfpc
Gravitational Radiation from Preheating with Many Fields
Parametric resonances provide a mechanism by which particles can be created
just after inflation. Thus far, attention has focused on a single or many
inflaton fields coupled to a single scalar field. However, generically we
expect the inflaton to couple to many other relativistic degrees of freedom
present in the early universe. Using simulations in an expanding
Friedmann-Lema\^itre-Robertson-Walker spacetime, in this paper we show how
preheating is affected by the addition of multiple fields coupled to the
inflaton. We focus our attention on gravitational wave production--an important
potential observational signature of the preheating stage. We find that
preheating and its gravitational wave signature is robust to the coupling of
the inflaton to more matter fields.Comment: 7 pages, 8 figures, v2 submission version, thank you for comments
Disk-Loss and Disk Renewal Phases in Classical Be Stars II. Detailed Analysis of Spectropolarimetric Data
In Wisniewski et al. 2010, paper I, we analyzed 15 years of spectroscopic and
spectropolarimetric data from the Ritter and Pine Bluff Observatories of 2 Be
stars, 60 Cygni and {\pi} Aquarii, when a transition from Be to B star
occurred. Here we anaylize the intrinsic polarization, where we observe
loop-like structures caused by the rise and fall of the polarization Balmer
Jump and continuum V-band polarization being mismatched temporally with
polarimetric outbursts. We also see polarization angle deviations from the
mean, reported in paper I, which may be indicative of warps in the disk, blobs
injected at an inclined orbit, or spiral density waves. We show our ongoing
efforts to model time dependent behavior of the disk to constrain the
phenomena, using 3D Monte Carlo radiative transfer codes.Comment: 2 pages, 6 figures, IAU Symposium 27
Liquid Phase Hydrodechlorination of Dieldrin and DDT over Pd/C and Raney-Ni
Selectivity and product distribution of hydrodechlorination (HDCl) of dieldrin and DDT are studied in different liquid phase systems,
namely in: (1) in ethanol; and (2) in the supported ionic liquid heterogeneous catalytic system (multiphase system), composed by the organic phase and aqueous KOH, a quaternary ammonium ionic liquid promoter (Aliquat 336), and a metal catalyst, e.g. 5% Pd/C, 5% Pt/C, or Raney-Ni. At 50 8C and atmospheric pressure of hydrogen, a quantitative hydrodechlorination of DDT in the biphasic system with ionic liquid layer is achieved in 40 min and in 4 h with Raney-Ni and Pd/C, respectively, while the reaction on Pt/C or on Pd/C without Aliquat 336 is slow. Dieldrin undergoes partial dechlorination, with high selectivity achievable only for its mono- and bi-dechlorination products. Dechlorination pathways and reactivity of different types of organic chlorine atoms versus the catalyst nature and other conditions are discussed
Race, Menopause, Health-Related Quality of Life, and Psychological Well-Being in Obese Women
Race, menopause, health-related quality of life, and psychological well-being in obese women. Obes Res. 2002;10:1270 â1275.
Objective: To investigate the health-related quality of life (HR-QOL) in African-American (AA) and white (W) obese women.
Research Methods and Procedures: Participants were 145 obese women (80 AA and 65 W; 87 premenopausal and 58 postmenopausal) who completed the Medical Outcomes Study short form, the Brief Symptom Inventory, the Life Distress Inventory, the Satisfaction With Life Scale, and the Rosenberg Self-Esteem Scale before entering a weight-loss study. The mean age of the subjects was 46.3 â 11.1 years and the mean body mass index was 35.2 â 4.2 kg/m2. Results: Although AA women were slightly heavier (95.3 â 10.3 kg vs. 91.5 â 11.6 kg, p â 0.05) and less educated (14.2 â 3.7 years vs. 15.7 â 3.7 years, p â 0.05) than the W women in the sample, there was no difference between the two ethnic groups in any of the reported HR-QOL variables. Menopausal status had a significant effect on HR-QOL, with premenopausal women being more distressed (p â 0.002), having more limitations in social activity (p â 0.007), and having less vitality (p â 0.001) than the postmenopausal women. This was especially true in the AA women.
Discussion: These data show no difference in HR-QOL between AA and W obese women and suggest that menopausal status may have an impact on HR-QOL, especially in AA women
Resource partitioning of phytoplankton metabolites that support bacterial heterotrophy
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ferrer-Gonzålez, F. X., Widner, B., Holderman, N. R., Glushka, J., Edison, A. S., Kujawinski, E. B., & Moran, M. A. Resource partitioning of phytoplankton metabolites that support bacterial heterotrophy. ISME Journal, (2020), doi:10.1038/s41396-020-00811-y.The communities of bacteria that assemble around marine microphytoplankton are predictably dominated by Rhodobacterales, Flavobacteriales, and families within the Gammaproteobacteria. Yet whether this consistent ecological pattern reflects the result of resource-based niche partitioning or resource competition requires better knowledge of the metabolites linking microbial autotrophs and heterotrophs in the surface ocean. We characterized molecules targeted for uptake by three heterotrophic bacteria individually co-cultured with a marine diatom using two strategies that vetted the exometabolite pool for biological relevance by means of bacterial activity assays: expression of diagnostic genes and net drawdown of exometabolites, the latter detected with mass spectrometry and nuclear magnetic resonance using novel sample preparation approaches. Of the more than 36 organic molecules with evidence of bacterial uptake, 53% contained nitrogen (including nucleosides and amino acids), 11% were organic sulfur compounds (including dihydroxypropanesulfonate and dimethysulfoniopropionate), and 28% were components of polysaccharides (including chrysolaminarin, chitin, and alginate). Overlap in phytoplankton-derived metabolite use by bacteria in the absence of competition was low, and only guanosine, proline, and N-acetyl-d-glucosamine were predicted to be used by all three. Exometabolite uptake pattern points to a key role for ecological resource partitioning in the assembly marine bacterial communities transforming recent photosynthate.This work was supported by grants from the Gordon and Betty Moore Foundation (5503) and the National Science Foundation (IOS-1656311) to MAM, ASE, and EBK, and by the Simons Foundation grant 542391 to MAM within the Principles of Microbial Ecosystems (PriME) Collaborative
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