4,726 research outputs found
Synthesis process and hydrodynamic behavior of a new filtration material for passive wastewater dephosphatation
International audienceThe preparation optimization of a filter material intended to be used as a phosphate sorbent in flow-through conditions is investigated. The mixing of ferrihydrite (Fh) and pozzolana (Pz) using a “dry contact method” is found to be the most efficient and leads to the formation of a micrometric thick Fh coating deposited into the honeycombed structure of Pz. The maximal Fh content of ~ 8.5 wt.% is significantly higher than the quantity deposited on other classical substrates such as sand. The phosphate sorption kinetics and isotherms, under dynamic conditions in batch experiments, are best described by pseudo-second-order and Freundlich models respectively. Moreover, under static conditions, sorption kinetics reveals intra-aggregate diffusion process. Phosphate ion retention in packed columns, and especially the breakthrough point, can be adequately predicted when coupling the classical convection dispersion equation and the surface complexation model. Breakthrough curves of phosphate ions are strongly dependent on flow rate; which is important for future industrial applications. Finally, and unexpectedly, a high value of phosphate adsorption capacity (80 mg PO4 g− 1) is observed when phosphate-containing wastewater is used as feed solution. This is mostly explained by soluble calcium ions, which favors the phosphate fixation onto the filter material surfac
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Stress rapidly suppresses in vivo LH pulses and increases activation of RFRP-3 neurons in male mice
Restraint stress is a psychosocial stressor that suppresses reproductive status, including LH pulsatile secretion, but the neuroendocrine mechanisms underlying this inhibition remains unclear. Reproductive neural populations upstream of gonadotropin-releasing hormone (GnRH) neurons, such as kisspeptin, neurokinin B and RFRP-3 (GnIH) neurons, are possible targets for psychosocial stress to inhibit LH pulses, but this has not been well examined, especially in mice in which prior technical limitations prevented assessment of in vivo LH pulse secretion dynamics. Here, we examined whether one-time acute restraint stress alters in vivo LH pulsatility and reproductive neural populations in male mice, and what the time-course is for such alterations. We found that endogenous LH pulses in castrated male mice are robustly and rapidly suppressed by one-time, acute restraint stress, with suppression observed as quickly as 12–18 min. This rapid LH suppression parallels with increased in vivo corticosterone levels within 15 min of restraint stress. Although Kiss1, Tac2 and Rfrp gene expression in the hypothalamus did not significantly change after 90 or 180 min restraint stress, arcuate Kiss1 neural activation was significantly decreased after 180 min. Interestingly, hypothalamic Rfrp neuronal activation was strongly increased at early times after restraint stress initiation, but was attenuated to levels lower than controls by 180 min of restraint stress. Thus, the male neuroendocrine reproductive axis is quite sensitive to short-term stress exposure, with significantly decreased pulsatile LH secretion and increased hypothalamic Rfrp neuronal activation occurring rapidly, within minutes, and decreased Kiss1 neuronal activation also occurring after longer stress durations
A report on the nonlinear squeezed states and their non-classical properties of a generalized isotonic oscillator
We construct nonlinear squeezed states of a generalized isotonic oscillator
potential. We demonstrate the non-existence of dual counterpart of nonlinear
squeezed states in this system. We investigate statistical properties exhibited
by the squeezed states, in particular Mandel's parameter, second-order
correlation function, photon number distributions and parameter in
detail. We also examine the quadrature and amplitude-squared squeezing effects.
Finally, we derive expression for the -parameterized quasi-probability
distribution function of these states. All these information about the system
are new to the literature.Comment: Accepted for publication in J. Phys. A: Math. Theo
Generation of Long-Lived Isomeric States via Bremsstrahlung Irradiation
A method to generate long-lived isomeric states effectively for Mossbauer
applications is reported. We demonstrate that this method is better and easier
to provide highly sensitive Mossbauer effect of long-lived isomers (>1ms) such
as 103Rh. Excitation of (gamma,gamma) process by synchrotron radiation is
painful due mainly to their limited linewidth. Instead,(gamma,gamma') process
of bremsstrahlung excitation is applied to create these long-lived isomers.
Isomers of 45Sc, 107Ag, 109Ag, and 103Rh have been generated from this method.
Among them, 103Rh is the only one that we have obtained the gravitational
effect at room temperature.Comment: ICAME 05 conference repor
Long Term Capsaicin Administration Effects on Skeletal Muscle Function in Aging Mice
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Intra-household evaluations of alcohol abuse in men with depression and suicide in women: A cross-sectional community-based study in Chennai, India.
BACKGROUND: Harmful effects of alcohol abuse are well documented for drinkers, and adverse effects are also reported for the physical and emotional well-being of family members, with evidence often originating from either drinkers or their families in clinic-based settings. This study evaluates intra-household associations between alcohol abuse in men, and depression and suicidal attempts in women, in community-based settings of Chennai, India. METHODS: This community-based cross-sectional study of chronic disease risk factors and outcomes was conducted in n = 259 households and n = 1053 adults (aged 15 years and above) in rural and urban Chennai. The Alcohol Use Disorder Identification Test (AUDIT) score was used to classify alcohol consumption into 'low-risk', 'harmful', 'hazardous' and 'alcohol dependence' drinking and the Patient Health Questionnaire (PHQ-9) score to classify depression as 'mild', 'moderate', 'moderate-severe' and 'severe'. Multivariate logistic regression models estimated the association of depression in women with men's drinking patterns in the same household. RESULTS: A significant 2.5-fold increase in any depression (PHQ-9 ≥ 5) was observed in men who were 'alcohol-dependent' compared to non-drinkers (OR = 2.53; 95% CI: 1.26, 5.09). However, there was no association between men's drinking behavior and depression in women of the same household, although suicidal attempts approached a significant dose-response relationship with increasing hazard-level of men's drinking (p = 0.08). CONCLUSION: No significant intra-household association was observed between men's alcohol consumption and women's depression, though an increasing (non-significant) trend was associated with suicidal attempts. Complex relationships between suicidal attempts and depression in women and male abusive drinking require further exploration, with an emphasis on intra-household mechanisms and pathways
WormBase 2007
WormBase (www.wormbase.org) is the major publicly available database of information about Caenorhabditis elegans, an important system for basic biological and biomedical research. Derived from the initial ACeDB database of C. elegans genetic and sequence information, WormBase now includes the genomic, anatomical and functional information about C. elegans, other Caenorhabditis species and other nematodes. As such, it is a crucial resource not only for C. elegans biologists but the larger biomedical and bioinformatics communities. Coverage of core areas of C. elegans biology will allow the biomedical community to make full use of the results of intensive molecular genetic analysis and functional genomic studies of this organism. Improved search and display tools, wider cross-species comparisons and extended ontologies are some of the features that will help scientists extend their research and take advantage of other nematode species genome sequences
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