2,451 research outputs found
Assessment of follicle density of leather from native brazilian goat breeds: quality criteria
The conservation in situ of zoogenetic resources requires the characterization of the production of local breeds. It is so far possible to evaluate and occasionally to improve the productive characters, making the breeding of those animals profitable for the producer. With this purpose a variety of works about the productive capacities of goat local breeds are being carried out in different countries, this contributing to avoid the biodiversity loss. The native goat breeds of Brazilian northeast highlight for their wildness, meat aptitude and skin usefulness. The final quality of the goat leather depends on a combination of factors that involve the whole process, from the livestock farmer to the leather transformation systems. The grain appearance of the leather characterizes the aesthetic-commercial value of the leather. A good appearance is given by a high and uniform follicle density. This work evaluates the superficial appearance of completed leathers of the breeds Moxotó and Canindé, highlighting the importance of the derived products of the local breeds, its contribution to the conservation of the genetic, cultural and socio-economic patrimony through differentiated products of high quality and the impact of the zoogenetic resources in the sustainable rural development of the semi-arid areas of Brazil.La conservación in situ de los recursos zoogenéticos requiere también la caracterización de la producción ligada a esas razas. Con ella se puede evaluar y en su caso mejorar los caracteres productivos, haciendo la cría de esas razas animales rentable para el ganadero. Con esta finalidad se vienen desarrollando diversos trabajos sobre las capacidades productivas de las razas locales caprinas en diversos países, contribuyendo así a evitar la pérdida de biodiversidad. Las razas caprinas nativas del nordeste brasileño destacan por su rusticidad, aptitud cárnica y el aprovechamiento de sus pieles. La calidad final del cuero de caprino depende de una combinación de factores que engloba desde el productor hasta el sistema de transformación. La apariencia de la superficie de la flor caracteriza el valor estético-comercial del cuero. La buena apariencia viene dada por la alta y uniforme densidad folicular. Este trabajo evalúa la apariencia superficial de cueros acabados de razas Moxotó y Canindé. Se pretende destacar la importancia de los productos derivados de las razas locales, su contribución a la conservación del patrimonio genético, cultural y socio-económico a través de productos diferenciados de alta calidad y el impacto de los recursos zoogenéticos en el desarrollo rural sostenible de las zonas semiáridas de Brasil
Consumers' perceptions and consumption behaviour concerning red fruits
Consumers' concern for disease prevention makes them aware of the importance to follow a healthy diet. Red fruits are known for their potential health benefits, namely due to their richness in antioxidants, vitamins and minerals.
To assess consumers’ perception of red fruits purchase, conservation, preparation and consumption habits and their potential health benefits.
A questionnaire was applied and distributed through e-mails and social media. From January to February of 2023, 507 individuals answered this survey. It focused on individuals’ perception of red fruits consumption and purchase habits; reasons, frequency and season of consumption; preparation and conservation procedures and potential health benefits.
Among all participants, 62.7% were aged between 18-29 years, 75.3% were females and 60.4% were from Lisbon. The majority had higher education (79.6%) and a considerable number had health qualifications (36.1%). 387 participants claimed to frequently consume red fruits. Those who do not consume essentially declared high price as the main reason (60.0%). Most people purchase red fruits at super and hypermarkets (88.4%), eat them mostly fresh in spring and summer, and keep them in the fridge until consumption. Strawberry was the most frequently consumed and cranberry was the least one. Vitamins (92.1%) and anthocyanins (44.4%) were the most common substances related to red berries. 49.1% of the participants considered red fruits to be more beneficial than others, associating them with antioxidant effects (87.8%), general health and well-being (69.6%), and prevention of diseases (71.8%) like cardiovascular diseases (73.9%) and cancer (57.4%).
Our findings suggest that most of this population consumes red fruits. It was verified a reasonable knowledge of their health benefits; however, several did not recognize their advantages, even having higher education. It is essential to enhance the spread of scientific information regarding the potential health benefits associated with the consumption of red fruits.this work was financially supported by INSA, I.P., under the project TradFRUIT (2012DAN668) and by European Union (FEDER funds through COMPETE), under the Partnership Agreement PT2020, and National Funds (FCT, Foundation for Science and Technology) through projects UIDB/50006/2020 and by AgriFood XXI I&D&I project (NORTE-01-0145-FEDER-000041) co-financed by European Regional Development Fund (ERDF), through the NORTE 2020 (Programa Operacional Regional do Norte 2014/2020).info:eu-repo/semantics/publishedVersio
Vortex behavior near a spin vacancy in 2D XY-magnets
The dynamical behavior of anisotropic two dimensional Heisenberg models is
still a matter of controversy. The existence of a central peak at all
temperatures and a rich structure of magnon peaks are not yet understood. It
seems that the central peaks are related, in some way, to structures like
vortices. In order to contribute to the discussion of the dynamical behavior of
the model we use Monte Carlo and spin dynamics simulations as well analytical
calculations to study the behavior of vortices in the presence of nonmagnetic
impurities. Our simulations show that vortices are attracted and trapped by the
impurities. Using this result we show that if we suppose that vortices are not
very much disturbed by the presence of the impurities, then they work as an
attractive potential to the vortices explaining the observed behavior in our
simulations.Comment: 4 pages, 6 figure
Leather: a contribution to sustainable goat production
Brazilian Northeast is a potentially good skin producer region due to its livestock farming activities which include more than 90% national goat cense. This exceptional situation with plenty raw material at hand, enables the development of familiar exploitations of goat skin tannery, thus recovering an activity linked to ancestral culture. Misevaluation of leather both by producers and industry, added to unstructured production and lack of research aimed to improve the quality of the final product could be key factors to the poor development of goat leather manufacture up to now in Northeast Brazil. Nevertheless, once transformed this product is reaching high values in international and Brazilian national markets, thus permitting it to became an important income source in the disfavoured Brazilian northeastern arid regions. If producers become aware of the value of their leather and if they are duly remunerated, industry will be offered better products and society will improve employment and performance. The main objective of the present paper is to contribute to point out the possibilities of leather production in the development of goat farming communities form disfavoured regions as a tool to improve the dignity and the quality of life of the producers. Moreover, the development of tannery in rural regions could help to the conservation of animal genetic resources (AGR) of local goat breeds thus contributing to sustainable development in arid or degraded regions.O Nordeste brasileiro, pela sua condição de região agropecuária, é potencialmente bom produtor de peles, superando 90% da população caprina nacional. Esta situação privilegiada, com a matéria-prima ao alcance da indústria coureira, pode permitir o desenvolvimento do curtume de peles de caprino de exploração familiar. Isto representaria a recuperação dessa atividade vinculada a uma cultura tradicional e a garantia de empregos numa região carente. A desvalorização da pele, como produto, pelo produtor e pela indústria, associada à desestruturação da produção, inexistência de cadeia produtiva e carência de pesquisa que contribua para obtenção de um produto de qualidade, são pontos críticos do freio no desenvolvimento da indústria de transformação da pele caprina. Porém, esta matéria-prima alcança alto valor no mercado internacional e nacional brasileiro, como produto transformado, sendo importante fonte de renda. Por isso, enquanto não houver consciência por parte do produtor e não houver remuneração justa da sua atividade, perde a indústria, pela oferta de matéria-prima de menor qualidade e, indiretamente, perde a sociedade, pela falta de geração de emprego e renda. O objetivo principal deste trabalho é contribuir para discussão das possibilidades sobre a produção do couro no desenvolvimento das comunidades caprinocultoras de zonas desfavoráveis do semi-árido nordestino, como ferramenta na melhoria da dignidade e qualidade de vida dos produtores. Além de tudo, o desenvolvimento do curtume em zonas rurais permitiria a conservação dos recursos genéticos animais de caprinos autóctones, contribuindo na direção da pesquisa para o desenvolvimento sustentável
Soil Chemical Attributes Of A Dystroferric Red Latosol (oxisol) Treated With An Alkaline Effluent From A Pharmaceutical Industry
Effluents from different industrial supply conglomerates are often discarded in the environment without proper treatment. The concern for an economically viable industrial production line, which is both environmentally sound and socially acceptable, is increasing. Some of these effluents are alkaline in nature and may be used as an alternative to chemical conditioners for acidic soils in agricultural systems. This research aimed to evaluate changes in the chemical attributes of a Dystroferric Red Latosol (Oxisol) after application of an effluent from a pharmaceutical industry. The experiment was conducted in a greenhouse using PVC tubes of 1-m length and a 0.2-m diameter filled with soil and different doses of the effluent. After 3 days, 100 mm of water was applied to each treatment. The PVC tubes were incubated for 30 days; thereafter, the tubes disassembled, and soil chemical analysis were made at different soil depths: 0-0.2, 0.2-0.4, 0.4-0.6, 0.6-0.8, and 0.8-1.0 m. The effluent applications significantly altered the soil elements in the 0-0.2 m layer, increasing the concentrations of K+, P, Mn2+, Na+, Cu2+, H+, Ca2+, Al3+ and the soil pH. In the subsurface layers, the concentration of the elements Zn2+, Cu2+, K+, and Na+ also changed significantly. In general, the application of pharmaceutical industry residue improved soil chemical attributes.3753037304
Comment on "Critique of q-entropy for thermal statistics" by M. Nauenberg
It was recently published by M. Nauenberg [1] a quite long list of objections
about the physical validity for thermal statistics of the theory sometimes
referred to in the literature as {\it nonextensive statistical mechanics}. This
generalization of Boltzmann-Gibbs (BG) statistical mechanics is based on the
following expression for the entropy:
S_q= k\frac{1- \sum_{i=1}^Wp_i^q}{q-1} (q \in {\cal R}; S_1=S_{BG} \equiv
-k\sum_{i=1}^W p_i \ln p_i) .
The author of [1] already presented orally the essence of his arguments in
1993 during a scientific meeting in Buenos Aires. I am replying now
simultaneously to the just cited paper, as well as to the 1993 objections
(essentially, the violation of "fundamental thermodynamic concepts", as stated
in the Abstract of [1]).Comment: 7 pages including 2 figures. This is a reply to M. Nauenberg, Phys.
Rev. E 67, 036114 (2003
Terahertz processes in carbon nanotubes
Copyright 2010 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.We investigated several proposals utilizing the unique electronic properties of carbon nanotubes (CNTs) for a broad range of applications to THz optoelectronics, including THz generation by Cerenkov-type emitters based on carbon nanotubes and by hot electrons in quasimetallic nanotubes, frequency multiplication in chiral-nanotube-based superlattices controlled by a transverse electric field, and THz radiation detection and emission by armchair nanotubes in a strong magnetic field. Dispersion equations of the electron beam instability and the threshold conditions of the stimulated emission have been derived and analyzed, demonstrating realizability of the nanotube-based nanoFEL at realistic parameters of nanotubes and electronic beams
Low Temperature Static and Dynamic Behavior of the Two-Dimensional Easy-Axis Heisenberg Model
We apply the self-consistent harmonic approximation (SCHA) to study static
and dynamic properties of the two-dimensional classical Heisenberg model with
easy-axis anisotropy. The static properties obtained are magnetization and spin
wave energy as functions of temperature, and the critical temperature as a
function of the easy-axis anisotropy. We also calculate the dynamic correlation
functions using the SCHA renormalized spin wave energy. Our analytical results,
for both static properties and dynamic correlation functions, are compared to
numerical simulation data combining cluster-Monte Carlo algorithms and Spin
Dynamics. The comparison allows us to conclude that far below the transition
temperature, where the SCHA is valid, spin waves are responsible for all
relevant features observed in the numerical simulation data; topological
excitations do not seem to contribute appreciably. For temperatures closer to
the transition temperature, there are differences between the dynamic
correlation functions from SCHA theory and Spin Dynamics; these may be due to
the presence of domain walls and solitons.Comment: 12 pages, 14 figure
The critical Ising model via Kac-Ward matrices
The Kac-Ward formula allows to compute the Ising partition function on any
finite graph G from the determinant of 2^{2g} matrices, where g is the genus of
a surface in which G embeds. We show that in the case of isoradially embedded
graphs with critical weights, these determinants have quite remarkable
properties. First of all, they satisfy some generalized Kramers-Wannier
duality: there is an explicit equality relating the determinants associated to
a graph and to its dual graph. Also, they are proportional to the determinants
of the discrete critical Laplacians on the graph G, exactly when the genus g is
zero or one. Finally, they share several formal properties with the Ray-Singer
\bar\partial-torsions of the Riemann surface in which G embeds.Comment: 30 pages, 10 figures; added section 4.4 in version
Continuous Percolation Phase Transitions of Two-dimensional Lattice Networks under a Generalized Achlioptas Process
The percolation phase transitions of two-dimensional lattice networks under a
generalized Achlioptas process (GAP) are investigated. During the GAP, two
edges are chosen randomly from the lattice and the edge with minimum product of
the two connecting cluster sizes is taken as the next occupied bond with a
probability . At , the GAP becomes the random growth model and leads
to the minority product rule at . Using the finite-size scaling analysis,
we find that the percolation phase transitions of these systems with are always continuous and their critical exponents depend on .
Therefore, the universality class of the critical phenomena in two-dimensional
lattice networks under the GAP is related to the probability parameter in
addition.Comment: 7 pages, 14 figures, accepted for publication in Eur. Phys. J.
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