Search Results - (Author, Cooperation:P. Monteiro)

2018-08-28

Molecular Diversity Preservation International (MPDI)

2072-6694

Medicine

2013-06-08

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Compulsive Behavior/*therapy ; Corpus Striatum/*physiopathology ; Disease Models, Animal ; Frontal Lobe/*physiopathology ; Gene Deletion ; Gene Targeting ; Grooming ; Male ; Mice ; Nerve Tissue Proteins/*genetics ; Neurons/physiology ; Optogenetics/*methods

2016-02-18

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

1572-932X

35K22 ; 34A60 ; evolution problem ; BV periodic solution ; sweeping process

Springer Online Journal Archives 1860-2000

Mathematics

Abstract This paper is concerned with BV periodic solutions for multivalued perturbations of an evolution equation governed by the sweeping process (or Moreau's process). The perturbed equation has the form −Du∈N C (t)(u(t))+F(t,u(t)), whereC is a closed convex valued continuousT-periodic multifunction from [0,T] to ℝ d ,N C (t)(u(t)) is the normal cone ofC(t) atu(t),F: [0,T]×ℝ d →ℝ d is a compact convex valued multifunction and Du is the differential measure of the periodic BV solutionu. Several existence results for this differential inclusion are stated under various assumptions on the perturbationF.

Electronic Resource

1573-2878

Calculus of variations ; nonconvex problems ; Baire category ; Liapunov theorem

Springer Online Journal Archives 1860-2000

Mathematics

Abstract This paper is concerned with the existence of a minimum in a Sobolev space for the functional $$F_g (x): = \int_0^T {g(x(t)){\text{ }}dt + \int_0^T {h(x'(t)){\text{ }}dt,{\text{ }}x(0) = a,{\text{ }}x(T) = b,} }$$ wherea,b are real numbers,g is a continuous map, andh is lower semicontinuous, satisfying adequate growth conditions. As shown by Cellina and Mariconda, there exists a dense subset of the space of continuous functions bounded below such that, forg in this subset, the above functional attains its minimum no matter whichh is used. This subset contains in particular the monotone maps, as shown by Marcellini, and the concave maps, as shown by Cellina and Colombo. Our aim is twofold: first to show that this subset, although dense, is meager in the sense of the Baire category; and second to show that it contains a class of functions which we call concave-monotone, because it generalizes both the classes of concave and of monotone functions.

Electronic Resource

2018-01-31

Wiley-Blackwell

0148-0227

Geosciences

Physics

1089-7550

AIP Digital Archive

Physics

The irreversible isothermal annealing of the as-deposited defects of hydrogenated amorphous silicon, a-Si:H, deposited at room temperature by concentric-electrode radio-frequency glow discharge is studied using dark and photoconductivity, space-charge limited current, and time-of-flight. The photoconductivity increases as a power law of the annealing time with exponent 0.8. The density of states at the Fermi level, measured by space-charge limited current, is inversely proportional to the annealing time. These results are compatible with bimolecular annealing kinetics. The dark conductivity obeys a Meyer–Nelder rule during the isothermal anneal.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

Co-Re metallic superlattices were prepared that show antiferromagnetic exchange coupling and enhanced saturation magnetoresistance for particular values of the Re spacer thickness. We report studies on films with the structure glass /150 A(ring) Re/[13 A(ring)Co/tRe]16/50 A(ring) Re, with tRe ranging from 3 to 40 A(ring). These structures were grown by magnetron sputtering in a system with a base pressure of 1×10−7 Torr with deposition rates of 0.3 and 0.4 A(ring)/s for Co and Re, respectively. x-ray diffractograms indicate the structure to be highly textured with the c axis perpendicular to the sample plane. The superlattice structure was obtained from high-angle θ-2θ scans. First-, second-, and third-order satellites are observed on both sides of the central [002] peak. Periodicity and bilayer composition are obtained from comparison of the data with a theoretical calculation of the x-ray diffractogram. Thickness calibration was confirmed by Rutherford backscattering and profilometer data. In-plane magnetization and magnetoresistance data (Δρ/ρ) indicate that stronger antiferromagnetic coupling and highest Δρ/ρ occur for tRe≈6 A(ring). The saturation field (Hs) needed to align contiguous antiferromagnetically coupled Co layers is about 1 T. This corresponds to an exchange coupling between the Co layer J≈−1 erg/cm2. (Δρ/ρ) reaches 2% in samples deposited at 170 °C. This data confirms results obtained by Parkin et al.1 in Co-Ru and Co-Cr superlattices.

Electronic Resource

1365-2826

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

A secondary surge of prolactin has been recently characterised on the afternoon of oestrus. Because the noradrenergic nucleus locus coeruleus participates in the genesis of the pro-oestrous and steroid-induced surges of prolactin, the aim of the present study was to investigate the importance of locus coeruleus norepinephrine in the generation of the prolactin surge of oestrus. For this purpose, we initially re-evaluated the profile of prolactin secretion during the oestrous cycle to verify whether this surge of prolactin was physiological and specific to the day of oestrus. Thereafter, the following were evaluated: (i) the effect of locus coeruleus lesion on the secondary surge of prolactin and on norepinephrine concentration in the medial preoptic area (MPOA), medial basal hypothalamus (MBH) and paraventricular nucleus (PVN) during the day of oestrus and (ii) locus coeruleus neurones activity during the same day by Fos immunoreactivity. Locus coeruleus lesion completely blocked the prolactin surge of oestrus in all rats studied and also significantly reduced norepinephrine concentration in the MPOA, MBH and PVN during the day of oestrus. The number of double-labelled tyrosine hydroxylase/Fos immunoreactive neurones in locus coeruleus was significantly higher at 14.00 h of oestrus, suggesting an increase in its activity preceding the prolactin surge that generally occurs at 15.00 h. Therefore, the increase in locus coeruleus activity on the afternoon of oestrus supports the data obtained with bilateral lesion of this nucleus, suggesting a stimulatory role of locus coeruleus norepinephrine in the genesis of the secondary surge of prolactin.

Electronic Resource

0889-1575

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Process Engineering, Biotechnology, Nutrition Technology

Electronic Resource

0304-8853

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Physics

Electronic Resource

0304-8853

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Physics

Electronic Resource

1359-5997

Springer Online Journal Archives 1860-2000

Architecture, Civil Engineering, Surveying

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Studies of stable carbon isotopes in fossil biological apatites have indicated the potential of using tooth enamel rather than bone for palaeoenvironmental and palaeodietary studies9"11. This method has been applied to analyses of Plio-Pleistocene ungulates from southern Africa10"12 and ...

Electronic Resource

1432-0479

JEL Classification Number: D52.

Springer Online Journal Archives 1860-2000

Economics

Summary. We show that when bankruptcy, subject to penalties, is allowed, it is possible to prove the existence of equilibrium in a model with a continuum of states without imposing any assumptions on ex-post endowments.

Electronic Resource

1432-0479

JEL Classification Number: D52.

Springer Online Journal Archives 1860-2000

Economics

Summary. We show that when bankruptcy, subject to penalties, is allowed, it is possible to prove the existence of equilibrium in a model with a continuum of states without imposing any assumptions on ex-post endowments.

Electronic Resource

1359-5997

Springer Online Journal Archives 1860-2000

Architecture, Civil Engineering, Surveying

Resume Il existe plusieurs méthodes de détermination du dosage d'un béton quand la résistance à la compression est prise comme critère de calcul; toutefois, on dispose de nettement moins de données quand il s'agit d'autres critères, tels l'énergie de rupture ou le module d'élasticité. Pour ces derniers cas, on a développé un nouveau nomogramme de formulation à partir des relations connues du béton. L'application de cette méthode est démontrée par un programme expérimental qui montre l'influence de la teneur en ciment, des rapports eau/ciment et granulat/ciment sur la résistance à la compression, le module d'élasticité et la résistance à la traction par fendage, l'énergie de rupture et la longueur caractéristique du béton. On a étudié six mélanges de béton présentant des rapports eau/ciment et une ouvrabilité différents. Outre qu'il est un outil pour le praticien, le nomogramme de formulation peut aussi aider le chercheur à sélectionner les paramètres de dosage les mieux appropriés à des buts expérimentaux et scientifiques. On remarque que certaines contraintes devraient être observées quand on étudie l'effect des paramètres de dosage sur les propriétés du béton.

Abstract There are many methods for determining a concrete mix proportion when the compressive strength is the design criterion; however, there is much less information available when other criteria, such as the fracture energy or the elastic modulus, are specified. For these cases, a new mix design nomogram has been developed from well-established concrete relationships. The application of this method is demonstrated by an experimental programme which shows the influence of cement content, water-to-cement ratio and aggregate-to-cement ratio on the compressive strength, modulus of elasticity, spliting tensile strength, fracture energy, and characteristic length of concrete. Six concrete mixtures with different water-to-cement ratios and workabilities were studied. The mix design nomogram, besides being a tool for the practitioner, can also help the researcher in selecting the most adequate mix parameters for experimental and scientific purposes. It is noted that when studying the effect of mix parameters on the properties of concrete certain constraints should be used: for instance when varying the water-to-cement ratio, the workability of fresh concrete should be kept constant and vice versa.

Electronic Resource

1573-4811

Springer Online Journal Archives 1860-2000

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Electronic Resource

1573-2878

Convex programming ; Lagrange multipliers ; subdifferentiability ; positive cones

Springer Online Journal Archives 1860-2000

Mathematics

Abstract In this note, we present a condition which is equivalent to the existence of the Lagrange multiplier for the general convex programming problem. This condition enables one to study a hypothesis distinct from the one of nonempty interior of the positive cone of the space of restrictions that is commonly used. Simple examples of this condition are given. We also explore the relationship of this condition with the subdifferentiability of the primal functional.

Electronic Resource