oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 216 )

2018 ( 332 )

2017 ( 296 )

2016 ( 405 )

Custom range...

Search Results: 1 - 10 of 175307 matches for " Jose E.; "
All listed articles are free for downloading (OA Articles)
Page 1 /175307
Display every page Item
Nutrient Use Efficiency of Three Fast Growing Hardwood Species across a Resource Gradient  [PDF]
Dawn E. Henderson, Shibu Jose
Open Journal of Forestry (OJF) , 2012, DOI: 10.4236/ojf.2012.24023
Abstract: Attitudes regarding traditional energy sources have shifted toward renewable resources. Specifically, short-rotation woody crop supply systems have become more prevalent for biomass and biofuel production. However, a number of factors such as environmental and inherent resource availability can limit tree production. Given the intensified demand for wood biomass production, forest and plantation management practices are focusing on increasing productivity. Fertilizer application, while generally one of the least expensive silvicultural tools, can become costly if application rates exceed nutrient uptake or demand of the trees especially if it does not result in additional biomass production. We investigated the effect of water and varying levels of nitrogen application (56, 112, and 224 kg·N·ha-1·yr-1) on nutrient content, resorption efficiency and proficiency, N:P and the relationship with ANPP, as well as leaf- and canopy-level nutrient use efficiency of nitrogen, phosphorus, and potassium for Populus deltoides, Quercus pagoda, and Platanus occidentalis. P. deltoides and P. occidentalis reached their maximum nitrogen budget with the application of water suggesting old agricultural fields may have sufficient nutrient levels to sustain short-rotation woody crops negating the application of additional nitrogen for these two species. Additionally, for P. deltoides and Q. pagoda application of nitrogen appeared to increase the uptake of phosphorus however, resorption efficiency for these two species were more similar to studies conducted on nutrient poor sites. Nutrient resorption proficiency for all three nutrients and all three species were at levels below the highest rates of nitrogen application. These findings suggest maximum biomass production may not necessarily be tied to maximum nutrient application.
Social Connectedness Predicts Lower Loneliness and Depressive Symptoms over Time in Adolescents  [PDF]
Paul E. Jose, Bee Teng Lim Lim
Open Journal of Depression (OJD) , 2014, DOI: 10.4236/ojd.2014.34019
Abstract:

Although research has shown that loneliness in adolescents leads to higher rates of depressive symptoms, the presumed protective factor of social connectedness has not been studied in conjunction with these two constructs. The aim of the present study was to determine if social connectedness would predict lower loneliness and depressive symptoms over time in a large sample of adolescents. A large sample of adolescents (N = 1774; 9-16 years at Time 1) were surveyed three times, separated by one year each, with self-report measures of social connectedness, loneliness, and depressive symptoms obtained. As expected, social connectedness was negatively associated with loneliness and depressive symptoms concurrently and longitudinally. Contrary to prediction, social connectedness did not function as a buffer between loneliness and depressive symptoms over time. However, consistent with prediction, a significant longitudinal mediation pattern was obtained over the three years: the effect of social connectedness on depressive symptoms was mediated by loneliness. Social connectedness at T1 predicted a reduction in loneliness at T2, which in turn predicted a reduction in depressive symptoms at T3. Moderation analyses of this mediation pattern suggested that this obtained mediation result was obtained for males, but not females, and obtained for older adolescents, but not for younger adolescents. The results are congruent with the view that social connectedness exerts an effective protective influence on adolescents against loneliness and depressive symptoms.

Specific permutation polynomials over finite fields
Jose E. Marcos
Mathematics , 2008,
Abstract: We present new classes of permutation polynomials over finite fields.
Impact of Water Chemistry on Lead Carbonate Dissolution in Drinking Water Distribution Systems  [PDF]
Maryam Mohammadzadeh, Onita D. Basu, Jose E. Herrera
Journal of Water Resource and Protection (JWARP) , 2015, DOI: 10.4236/jwarp.2015.75031
Abstract: Elemental lead is a known toxic metal that can pose threats to human health and can be found in a variety of sources including drinking water at very low level concentrations (i.e. μg/L range). Destabilization of the corrosion scale at the inner layer of pipeline is the major source of lead in drinking water. Chemical properties of the water passing through the distribution system such as pH, alkalinity, chlorine content, oxidation reduction potential (ORP) and natural organic matters will affect the formation and/or destabilization of the corrosion scale. This research examines the impact of pH values (7.0 - 9.5), temperatures (5°;C vs 20°;C) and alkalinity levels (moderate vs low), in the presence of chlorine, on dissolution of hydrocerussite and cerussite in drinking water by various sets of batch dissolution experiments. The results showed dissolution of cerussite and hydrocerussite was not impacted significantly by pH ranging 7.0 - 9.5. In addition, and somewhat surprisingly, cold temperature (5°;C) and moderate alkalinity showed a great influence on decreasing the solubility of lead species.
Holomorphic geometric models for representations of $C^*$-algebras
Daniel Beltita,Jose E. Gale
Mathematics , 2007,
Abstract: Representations of $C^*$-algebras are realized on section spaces of holomorphic homogeneous vector bundles. The corresponding section spaces are investigated by means of a new notion of reproducing kernel, suitable for dealing with involutive diffeomorphisms defined on the base spaces of the bundles. Applications of this technique to dilation theory of completely positive maps are explored and the critical role of complexified homogeneous spaces in connection with the Stinespring dilations is pointed out. The general results are further illustrated by a discussion of several specific topics, including similarity orbits of representations of amenable Banach algebras, similarity orbits of conditional expectations, geometric models of representations of Cuntz algebras, the relationship to endomorphisms of ${\mathcal B}({\mathcal H})$, and non-commutative stochastic analysis.
Universal objects in categories of reproducing kernels
Daniel Beltita,Jose E. Gale
Mathematics , 2009,
Abstract: We continue our earlier investigation on generalized reproducing kernels, in connection with the complex geometry of $C^*$- algebra representations, by looking at them as the objects of an appropriate category. Thus the correspondence between reproducing $(-*)$-kernels and the associated Hilbert spaces of sections of vector bundles is made into a functor. We construct reproducing $(-*)$-kernels with universality properties with respect to the operation of pull-back. We show how completely positive maps can be regarded as pull-backs of universal ones linked to the tautological bundle over the Grassmann manifold of the Hilbert space $\ell^2({\mathbb N})$.
The metazoan parasites of Stellifer minor (Tschudi, 1844): an ecological approach
Oliva, Marcelo E.;Luque, Jose L.;Iannacone, Jose A.;
Memórias do Instituto Oswaldo Cruz , 1990, DOI: 10.1590/S0074-02761990000300003
Abstract: a quantitative and qualitative analysis of the parasite fauna of the sciaenid stellifer minor (tschudi) from chorrillos, peru, was made. some characteristics of the infectious processes, in terms of intensity and prevalence of infection, as a function of host sex and size, are given. moreover, comments on the characteristics of the parasite fauna, related with host role in the marine food webs are included. the parasite fauna of stellifer minor taken of chorrillos, peru, include the monogeneans pedocotyle annakohni, pedocotyle bravoi, rhamnocercus sp. and cynoscionicola sp., the digenean helicometra fasciata, the adult acantocephalan rhadinorhynchus sp. and the larval corynosoma sp., the nematode procamallanus sp., the copepods caligus quadratus, clavellotis dilatata and bomolochus peruensis and one unidentified isopod of the family cymothoidae. a distinctive characteristic of the parasite fauna (metazoa) of s. minor is the almost absence of larval forms.
Dielectric and Mechanical Nonlinear Behavior of Mn Doped PMN-35PT Ceramics  [PDF]
Diouma Kobor, Abdelowahed Hajjaji, Jose E. Garcia, Rafel Perez, Alfons Albareda, Laurent Lebrun, Daniel Guyomar
Journal of Modern Physics (JMP) , 2010, DOI: 10.4236/jmp.2010.14032
Abstract: This paper presents an investigation on dielectric and mechanical nonlinear properties in Mn-doped PMN-35PT ceramics. The structural study of the ceramics verifies that the 1% mol Mn doped PMN-35PT is a pure perovskite phase with a tetragonal symmetry. SEM micrograph shows the same microstructural mor- phology of an undoped ceramic. From the EPR spectra, it has been concluded that the major part of Mn is present in Mn2+ rather than in Mn4+ form. The addition of Mn2+ ions acts on the dielectric, piezoelectric and mechanical properties by decreasing the relative dielectric permittivity (3800 to 2074), the dielectric losses (0.60 to 0.53), the piezoelectric coefficient d33 (650 to 403 pC/N), and increasing the mechanical quality fac- tor Qm (78 to 317). It was found that in Mn2+ doped ceramics the dielectric response can not be described by Rayleigh law. This result can be understood taking into account that reversible motion of the domain wall is a relevant contribution to response of this material.
The genus lobatostoma (Trematoda: Aspidocotylea) in the pacific coast of South America, with description of Lobatostoma veranoi new species, parasite of Menticirrhus ophycephalus (Teleostei: Sciaenidae)
Oliva, Marcelo E.;Luque, Jose L.;
Memórias do Instituto Oswaldo Cruz , 1989, DOI: 10.1590/S0074-02761989000200004
Abstract: the presence of three aspidocotyleans trematodes in marine fishes from perú and chile is reported. one of them, lobatostoma veranoi from the intestine of menticirrhus ophicephalu (sciaenidae) is considered a new species. distinct characteristcs of the new species are:a cirrus sac smaller than the pharynx; tail overlapping posteriorly the ventral disk; testis in the last third of the body and the presence of 64-66 marginal alveoli. the two other species are lobatostoma pacificum manter, 1940 found in trachinotus paitensis cuvier, 1830 from perú and chile and lobatostoma anisotremum oliva & carvajal, 1984 from the intestine of anisotremus scapularis (tschudi, 1844) from perú.
SYNTHESIS AND CHARACTERIZATION OF MANGANESE COLLOIDS AND ACTIVE SOLIDS PREPARED WITH ORGANICS SOLVENTS
CARDENAS T.,GALO; ACU?A E.,JOSE;
Boletín de la Sociedad Chilena de Química , 2000, DOI: 10.4067/S0366-16442000000300022
Abstract: manganese colloids were prepared by cocondensation of the metal at 77k with ethanol, 2-propanol, 1,2-dimethoxyethane, 2-methoxyethanol and acetone. the distribution of particle sizes was determined by transmission electron microscopy of the most stable dispersions. electrophoretic measurements such as: colloid load and zeta potential were achieved. lt was found that the colloids do not possess electrical charge, therefore it is postulated that their stability is by simple solvation. the colloids showed instability at room temperature. in some colloids absorption bands in the uv region were observed. in the visible region no plasma absorption was found. active solids obtained by evaporation of the solvent contain certain amount of the solvent incorporated, and due to their reactivity they produce a mixture with manganese oxide. the presence of solvents can be observed and their incorporation in the finely divided solids can be observed by ft-ir. characteristic bands for each solvent were measured. the tga - ftir shows the presence of the c = o and c - h bands indicating the acetone in the solid. by means of thermogravimetric analysis and dsc the thermal stability of the solids and the transition heat from the thermal analysis can be determined.
Page 1 /175307
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.