1,313 research outputs found
Evaluation of a simplified model for estimating energy balance in broilers production housing
The simulation of poultry house thermal behavior with and without Adiabatic Evaporative Cooling (SRAE) allows the decision makers to evaluate the economical feasibility and the installation costs of a poultry production business. The first step in this research investigation was test the thermal behavior model developed by Gates et al. (1995) for broiler houses in the United States based on the hypothesis that this model, using climatized sheds, as proposed by the authors, could be used under Brazilian conditions. The model is suitable for the proposed objective in the form proposed by Gates et al. (1995) for poultry houses with an elevated mass air flow rate (120.8 kg air s -1 or higher). A correction factor referring to a series of heat sources not included in the model, or the inclusion of these sources, is necessary for poultry houses without a high mass air flow.A simulação do comportamento térmico de galpões avícolas com e sem Sistemas de Resfriamento Adiabáticos Evaporativos (SRAE) permite aos tomadores de decisão avaliarem a viabilidade econômica e os custos da instalação de um empreendimento na avicultura de corte. Para operacionalização desta investigação, o primeiro passo foi a execução do teste do modelo de comportamento térmico desenvolvido por Gates et al. (1995) para galpões avícolas nos Estados Unidos, com base na hipótese de que este modelo, utilizando-se galpões climatizados, como sugerido pelos autores, possa ser usado em condições brasileiras. O modelo se mostrou adequado para o objetivo previsto, na forma indicada por Gates et al. (1995) para galpões com vazão mássica do ar elevada, (120,8 kg de ar por segundo ou maior). É necessário um fator de correção referente a uma série de fontes de calor desprezada pelo modelo para galpões sem uma grande vazão mássica, ou a inclusão dessas fontes
Unit Commitment in a Competitive and Emission Constrained Environment
This paper is on the unit commitment problem, considering not only the economic perspective, but also the environmental perspective. We propose a bi-objective approach to handle the problem with conflicting profit and emission objectives. Numerical results based on the standard IEEE 30-bus test system illustrate the proficiency of the proposed approach
Nonlinear optimization method for short-term hydro scheduling considering head-dependency
This paper is on the problem of short-term hydro scheduling, particularly concerning head-dependent reservoirs under competitive environment. We propose a new nonlinear optimization method to consider hydroelectric power generation as a function of water discharge and also of the head. Head-dependency is considered on short-term hydro scheduling in order to obtain more realistic and feasible results. The proposed method has been applied successfully to solve a case study based on one of the main Portuguese cascaded hydro systems, providing a higher profit at a negligible additional computation time in comparison with a linear optimization method that ignores head-dependency
A practical approach for profit-based unit commitment with emission limitations
This paper proposes a practical approach for profit-based unit commitment (PBUC) with emission limitations. Under deregulation, unit commitment has evolved from a minimum-cost optimisation problem to a profit-based optimisation problem. However, as a consequence of growing environmental concern, the impact of fossil-fuelled power plants must be considered, giving rise to emission limitations. The simultaneous address of the profit with the emission is taken into account in our practical approach by a multiobjective optimisation (MO) problem. Hence, trade-off Curves between profit and emission are obtained for different energy price profiles, in a way to aid decision-makers concerning emission allowance trading. Moreover, a new parameter is presented, ratio of change, and the corresponding gradient angle, enabling the proper selection of a compromise commitment for the units. A case study based on the standard IEEE 30-bus system is presented to illustrate the proficiency Of Our practical approach for the new competitive and environmentally constrained electricity supply industry
SIMBA: a web tool for managing bacterial genome assembly generated by Ion PGM sequencing technology
Background The evolution of Next-Generation Sequencing (NGS) has considerably reduced the cost per sequenced-base, allowing a significant rise of sequencing projects, mainly in prokaryotes. However, the range of available NGS platforms requires different strategies and software to correctly assemble genomes. Different strategies are necessary to properly complete an assembly project, in addition to the installation or modification of various software. This requires users to have significant expertise in these software and command line scripting experience on Unix platforms, besides possessing the basic expertise on methodologies and techniques for genome assembly. These difficulties often delay the complete genome assembly projects. Results In order to overcome this, we developed SIMBA (SImple Manager for Bacterial Assemblies), a freely available web tool that integrates several component tools for assembling and finishing bacterial genomes. SIMBA provides a friendly and intuitive user interface so bioinformaticians, even with low computational expertise, can work under a centralized administrative control system of assemblies managed by the assembly center head. SIMBA guides the users to execute assembly process through simple and interactive pages. SIMBA workflow was divided in three modules: (i) projects: allows a general vision of genome sequencing projects, in addition to data quality analysis and data format conversions; (ii) assemblies: allows de novo assemblies with the software Mira, Minia, Newbler and SPAdes, also assembly quality validations using QUAST software; and (iii) curation: presents methods to finishing assemblies through tools for scaffolding contigs and close gaps. We also presented a case study that validated the efficacy of SIMBA to manage bacterial assemblies projects sequenced using Ion Torrent PGM. Conclusion Besides to be a web tool for genome assembly, SIMBA is a complete genome assemblies project management system, which can be useful for managing of several projects in laboratories. SIMBA source code is available to download and install in local webservers at http://ufmg-simba.sourceforge.net
Where the risk is more intense: riparian forests keep the euglossine bees community most affected by anthropic disturbance in the Caatinga dry forest.
Anthropogenic disturbances have drastic negative effects on the biodiversity, thereby also compromising the ecosystem service it provides. Bees are one of the key players since they provide essential pollination services for both natural and agriculture ecosystems. Nevertheless, these insects are facing an increasing threat due to expansion of urban areas and inappropriate land use practices. Therefore, understanding the impact of different anthropogenic disturbances on bee communities is essential to assure the ecosystem functioning and human well-being. In this study, we made use of a well-known bee group, i.e., euglossine bees (Euglossine: Apidae), and of a fast-growing city to investigate the impact of anthropogenic disturbance on bee community. Using scent traps, we monthly collected male euglossine bees in seven sampling areas, differing in terms of the anthropogenic use/disturbance. Land use in each area was characterized through pre-georeferenced images and mapping software and from these data we calculated an Anthropogenic Transformation Index. Our results reveal that anthropogenic disturbance negatively impacts the euglossine bee community, in contrast to the positive effect of the proximity to the river. However, and perhaps the most alarming aspect of our findings, is the interaction effect between these two conditions, demonstrating that as we approach the river, parameters such as abundance, species richness, and diversity of these bee communities become more compromised by disturbance. Our study shows the urgent need to implement effective conservation strategies and sustainable management practices to protect and restore riparian forests in Caatinga urban areas, aiming to safeguard its associated biota and the valuable ecosystem services they provide.On-line
Dissecting EPPIN protease inhibitor domains in sperm motility and fertilizing ability: Repercussions for male contraceptive development
EPPIN (epididymal protease inhibitor) is a mammalian conserved sperm-binding protein displaying an N-terminal WFDC (whey-acidic protein four-disulfide core) and a C-terminal Kunitz protease inhibitor domains. EPPIN plays a key role in regulating sperm motility after ejaculation via interaction with the seminal plasma protein SEMG1 (semenogelin-1). EPPIN ligands targeting the SEMG1 binding site in the Kunitz domain are under development as male contraceptive drugs. Nevertheless, the relative contributions of EPPIN WFDC and Kunitz domains to sperm function remain obscure. Here, we evaluated the effects of antibodies targeting specific epitopes in EPPIN's WFDC (Q20E antibody, Gln20-Glu39 epitope) and Kunitz (S21C and F21C antibodies, Ser103-Cys123 and Phe90-C110 epitopes, respectively) domains on mouse sperm motility and fertilizing ability. Computer-assisted sperm analysis showed that sperm co-incubation with S21C antibody (but not F21C antibody) lowered progressive and hyperactivated motilities and impaired kinematic parameters describing progressive (straight-line velocity; VSL, average path velocity; VAP and straightness; STR) and vigorous sperm movements (curvilinear velocity; VCL, amplitude of lateral head movement; ALH, and linearity; LIN) compared with control. Conversely, Q20E antibody-induced milder inhibition of progressive motility and kinematic parameters (VAP, VCL and ALH). Sperm co-incubation with S21C or Q20E antibodies affected in vitro fertilization as revealed by reduced cleavage rates, albeit without changes in capacitation-induced tyrosine phosphorylation. In conclusion, we show that targeting specific epitopes in EPPIN Kunitz and WFDC domains inhibits sperm motility and capacitation-associated events, which decrease their fertilizing ability; nevertheless, similar observations in vivo remain to be demonstrated. Simultaneously targeting residues in S21C and Q20E epitopes is a promising approach for the rational design of EPPIN-based ligands with spermostatic activity.Fil: Silva, Alan A. S.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Raimundo, Tamiris R. F.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Mariani, Noemia A. P.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Kushima, Hélio. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Avellar, Maria Christina W.. Universidade Federal de Sao Paulo; BrasilFil: Buffone, Mariano Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Paula Lopes, Fabíola F.. Universidade Federal de Sao Paulo; BrasilFil: Moura, Marcelo T.. Universidade Federal de Sao Paulo; BrasilFil: Silva, Erick J. R.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi
Magnetic and transport properties of diluted granular multilayers
The magnetic and transport properties of Co80Fe20t /Al2O34 nm multilayers with low nominal thicknesses t=0.7 and 0.9 nm of Co80Fe20 granular layers are studied. Magnetic studies find a superparamagnetic state above the blocking temperature Tb of field-cooled/zero-field-cooled splitting that grows with t and decreases with H. The low-voltage Ohmic tunnel transport passes to
non-Ohmic IV3/2 law for applied fields above 500 V/cm. At fixed V, the temperature dependence of conductance reveals an anomalous dip around 220 K, which can be attributed to the effect of surface contamination by supercooled water. Current-in-plane tunnel magnetoresistance MR ratio tends, at lower t, to higher maximum values 8% at room temperature but to lower field sensitivity. This may indicate growing discorrelation effect e.g., between shrinking areas of correlated moments in this regime and corroborates the deficit of granule magnetization estimated from the Inoue–Maekawa MR fit, compared to that from direct magnetization measurements. MR displays a mean-field-like critical behavior when t approaches the point of superparamagnetic/ superferromagnetic transition tc1.3 nm at room temperature from below, different from the formerly reported percolationlike behavior at approaching it from above.With growing temperature, MR reveals, beyond the common decrease, an anomalous plateau from Tb30–50 K up to some
higher value T150–200 K, not seen at higher t
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