407 research outputs found
Enrichissement en protéines du tourteau de coprah : sélection de champignons filamenteux en FMS = Protein enrichment of copra cake : selection of filamentous fungi in SSF
Les résultats ont montré que 11 souches sur 51 testées peuvent être retenues. Elles appartiennent aux espèces #Aspergillus sp., #Aspergillus niger, Penicillium italicum, Penicillium sp. et #Penicillium roquefortii$. Le rendement moyen d'enrichissement en protéines est de 20 %. Toutefois l'objectif n'est pas totalement atteint. Une optimisation des conditions de culture, en particulier, de la composition des milieux de culture, s'impose afin d'augmenter ces rendements protéiques et atteindre 50 %
Further Studies on the Lyo and Desmo Components of Several Hydrolytic Enzymes and Their Histochemical Significance
Melanopsin as a Sleep Modulator: Circadian Gating of the Direct Effects of Light on Sleep and Altered Sleep Homeostasis in Opn4−/− Mice
Analyses in mice deficient for the blue-light-sensitive photopigment melanopsin show that direct effects of light on behavior and EEG depend on the time of day. The data further suggest an unexpected role for melanopsin in sleep homeostasis
Quantum Time and Spatial Localization: An Analysis of the Hegerfeldt Paradox
Two related problems in relativistic quantum mechanics, the apparent
superluminal propagation of initially localized particles and dependence of
spatial localization on the motion of the observer, are analyzed in the context
of Dirac's theory of constraints. A parametrization invariant formulation is
obtained by introducing time and energy operators for the relativistic particle
and then treating the Klein-Gordon equation as a constraint. The standard,
physical Hilbert space is recovered, via integration over proper time, from an
augmented Hilbert space wherein time and energy are dynamical variables. It is
shown that the Newton-Wigner position operator, being in this description a
constant of motion, acts on states in the augmented space. States with strictly
positive energy are non-local in time; consequently, position measurements
receive contributions from states representing the particle's position at many
times. Apparent superluminal propagation is explained by noting that, as the
particle is potentially in the past (or future) of the assumed initial place
and time of localization, it has time to propagate to distant regions without
exceeding the speed of light. An inequality is proven showing the Hegerfeldt
paradox to be completely accounted for by the hypotheses of subluminal
propagation from a set of initial space-time points determined by the quantum
time distribution arising from the positivity of the system's energy. Spatial
localization can nevertheless occur through quantum interference between states
representing the particle at different times. The non-locality of the same
system to a moving observer is due to Lorentz rotation of spatial axes out of
the interference minimum.Comment: This paper is identical to the version appearing in J. Math. Phys.
41; 6093 (Sept. 2000). The published version will be found at
http://ojps.aip.org/jmp/. The paper (40 page PDF file) has been completely
revised since the last posting to this archiv
A Systematic Review of Music Therapy Practice and Outcomes with Acute Adult Psychiatric In-Patients
PMCID: PMC3732280This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Covariance properties and regularization of conserved currents in tetrad gravity
We discuss the properties of the gravitational energy-momentum 3-form within
the tetrad formulation of general relativity theory. We derive the covariance
properties of the quantities describing the energy-momentum content under
Lorentz transformations of the tetrad. As an application, we consider the
computation of the total energy (mass) of some exact solutions of Einstein's
general relativity theory which describe compact sources with asymptotically
flat spacetime geometry. As it is known, depending on the choice of tetrad
frame, the formal total integral for such configurations may diverge. We
propose a natural regularization method which yields finite values for the
total energy-momentum of the system and demonstrate how it works on a number of
explicit examples.Comment: 36 pages, Revtex, no figures; small changes, published versio
Circadian Behaviour in Neuroglobin Deficient Mice
Neuroglobin (Ngb), a neuron-specific oxygen-binding globin with an unknown function, has been proposed to play a key role in neuronal survival. We have previously shown Ngb to be highly expressed in the rat suprachiasmatic nucleus (SCN). The present study addresses the effect of Ngb deficiency on circadian behavior. Ngb-deficient and wild-type (wt) mice were placed in running wheels and their activity rhythms, endogenous period and response to light stimuli were investigated. The effect of Ngb deficiency on the expression of Period1 (Per1) and the immediate early gene Fos was determined after light stimulation at night and the neurochemical phenotype of Ngb expressing neurons in wt mice was characterized. Loss of Ngb function had no effect on overall circadian entrainment, but resulted in a significantly larger phase delay of circadian rhythm upon light stimulation at early night. A light-induced increase in Per1, but not Fos, gene expression was observed in Ngb-deficient mice. Ngb expressing neurons which co-stored Gastrin Releasing Peptide (GRP) and were innervated from the eye and the geniculo-hypothalamic tract expressed FOS after light stimulation. No PER1 expression was observed in Ngb-positive neurons. The present study demonstrates for the first time that the genetic elimination of Ngb does not affect core clock function but evokes an increased behavioural response to light concomitant with increased Per1 gene expression in the SCN at early night
Pituitary Adenylate Cyclase-Activating Polypeptide Stimulates Glucose Production via the Hepatic Sympathetic Innervation in Rats
OBJECTIVE-The unraveling of the elaborate brain networks that control glucose metabolism presents one of the current challenges in diabetes research. Within the central nervous system, the hypothalamus is regarded as the key brain area to regulate energy homeostasis. The aim of the present study was to investigate the hypothalamic mechanism involved in the hyperglycemic effects of the neuropeptide pituitary adenylyl cyclase-activating polypeptide (PACAP). RESEARCH DESIGN AND METHODS-Endogenous glucose production (EGP) was determined during intracerebroventricular infusions of PACAP-38, vasoactive intestinal peptide (VIP), or their receptor agonists. The specificity of their receptors was examined by coinfusions of receptor antagonists. The possible neuronal pathway involved was investigated by 1) local injections in hypothalamic nuclei, 2) retrograde neuronal tracing from the thoracic spinal cord to hypothalamic preautonomic neurons together with Fos immunoreactivity, and 3) specific hepatic sympathetic or parasympathetic denervation to block the autonomic neuronal input to liver. LTS-Intracerebroventiicular infusion of PACAP-38 increased EGP to a similar extent as a VIP/PACAP-2 (VPAC2) receptor agonist, and intracerebroventricular administration of VIP had significantly less influence on EGP. The PACAP-38 induced increase of EGP was significantly suppressed by preinfusion of a VPAC2 but not a PAC1 receptor antagonist, as well as by hepatic sympathetic but not parasympathetic denervation. In the hypothalamus, Fos immunoreactivity induced by PACAP-38 was colocalized within autonomic neurons in paraventricular nuclei projecting to preganglionic sympathetic neurons in the spinal cord. Local infusion of PACAP-38 directly into the PVN induced a significant increase of EGP. CONCLUSIONS-This study demonstrates that PACAP-38 signaling via sympathetic preautonomic neurons located in the paraventricular nucleus is an important component in the hypothalamic control of hepatic glucose production. Diabetes 59: 1591-1600, 201
Field on Poincare group and quantum description of orientable objects
We propose an approach to the quantum-mechanical description of relativistic
orientable objects. It generalizes Wigner's ideas concerning the treatment of
nonrelativistic orientable objects (in particular, a nonrelativistic rotator)
with the help of two reference frames (space-fixed and body-fixed). A technical
realization of this generalization (for instance, in 3+1 dimensions) amounts to
introducing wave functions that depend on elements of the Poincare group . A
complete set of transformations that test the symmetries of an orientable
object and of the embedding space belongs to the group . All
such transformations can be studied by considering a generalized regular
representation of in the space of scalar functions on the group, ,
that depend on the Minkowski space points as well as on the
orientation variables given by the elements of a matrix .
In particular, the field is a generating function of usual spin-tensor
multicomponent fields. In the theory under consideration, there are four
different types of spinors, and an orientable object is characterized by ten
quantum numbers. We study the corresponding relativistic wave equations and
their symmetry properties.Comment: 46 page
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