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951.
Diego F. García Belén García Juan Carlos Burgos Néstor García-Hernando 《International Journal of Heat and Mass Transfer》2012,55(4):1066-1075
This paper presents the methodology used and the results obtained in the determination of moisture diffusion coefficient of non-impregnated transformer insulating paper. In order to establish the diffusion coefficient, drying curves of paper samples were obtained by means of thermogravimetric experiments. The diffusion coefficient parameters were found by applying an optimization process based on genetic algorithms. The error function between measured and simulated curves was determined, and the parameters achieving the best correspondence between measured and estimated values were obtained. As a result, a new equation for the diffusion coefficient of non-impregnated insulating paper is proposed, depending on average moisture concentration, temperature and insulation thickness. The proposed coefficient was validated through experimental cases finding a good agreement between the experimental drying curves and those obtained by simulation using the diffusion coefficient. The proposed diffusion coefficient can be used for the determination of the time required to dry power transformers in factory. 相似文献
952.
The future economic growth for India is likely to result in rapid and accelerated surge in energy demand, with expected shortages in terms of supply. Many of its current policies and strategies are aimed at the improvement and possible maximization of energy production from the renewable sector. It is also clear that while energy conservation and energy efficiency can make an important contribution, renewable energies will be essential to the solution and are likely to play an increasingly important role for providing enhanced energy access, reducing consumption of fossil fuels, and helping India pursue its low-carbon progressive pathway. However, most of the states in India, like the northernmost state of Jammu and Kashmir, have experienced an energy crisis over a sustained period of time and the government both at center and state level has to embark upon with these pressing issues in a more sustainable manner and accordingly initiate various renewable energy projects within these states. This paper will provide a broad-spectrum view about the energy situation within Jammu and Kashmir and will highlight the current policies along with future strategies for the optimal utilization of renewable energy resources. 相似文献
953.
Diego Borin Nobrega Aline Parolin Calarga Leandro Costa Nascimento Carla Gasparotto Chande Vasconcelos Eliane Martins de Lima Helio Langoni Marcelo Brocchi 《Journal of dairy science》2021,104(6):7210-7224
In this observational study, phenotypic and genotypic patterns of antimicrobial resistance (AMR) in Klebsiella pneumoniae isolated from intramammary infections, clinical mastitis, fresh feces, rectal swabs, animal hindlimbs, and bulk tank milk samples from Brazilian dairy herds were investigated. In addition, we identified specific genetic variants present among extended-spectrum β-lactamase (ESBL) producers. We obtained 169 isolates of K. pneumoniae from 2009 to 2011 on 24 Brazilian dairy farms located in 4 Brazilian states. The AMR profile of all isolates was determined using disk-diffusion assays. The antimicrobial panel included drugs commonly used as mastitis treatment in Brazilian dairy herds (gentamicin, cephalosporins, sulfamethoxazole-trimethoprim, tetracycline) as well as antimicrobials of critical importance for human health (meropenem, ceftazidime, fluoroquinolones). The K. pneumoniae isolates resistant to tetracycline, fluoroquinolones, sulfamethoxazole-trimethoprim, or chloramphenicol were screened for presence of drug-specific AMR genes [tet, qnr, aac(6')-Ib, floR, catA2, cm1A, dfr, sul] using PCR. In addition, we identified ESBL genes present among ESBL-producers by using whole genome sequencing. Genomes were assembled and annotated, and patterns of AMR genes were investigated. Resistance was commonly detected against tetracycline (22.5% of all isolates), streptomycin (20.7%), and sulfamethoxazole-trimethoprim (9.5%). Antimicrobial resistance rates were higher in K. pneumoniae isolated from intramammary infections in comparison with isolates from feces (19.2 and 0% of multidrug resistance in intramammary and fecal isolates, respectively). In contrast, no difference in AMR rates was observed when contrasting hind limbs and isolates from intramammary infections. The genes tetA, sul2, and floR were the most frequently observed AMR genes in K. pneumoniae resistant to tetracycline, sulfamethoxazole-trimethoprim, and chloramphenicol, respectively. The tetA gene was present exclusively in isolates from milk. The genes blaCTX-M8 and blaSHV-108 were present in 3 ESBL-producing K. pneumoniae, including an isolate from bulk tank milk. The 3 isolates were of sequence type 281 and had similar mobile genetic elements and virulence genes. Our study reinforced the epidemiological importance and dissemination of blaCTX-M-8 pST114 plasmid in food-producing animals in Brazil. 相似文献
954.
Yuri Buratto de Farias Anderson Kaiszewski Coutinho Diego Santiago Tupuna-Yerovi Alessandro de Oliveira Rios 《应用聚合物科学杂志》2021,138(8):49876
Alginate is a biopolymer with film-forming properties that can be used as food packaging material. Norbixin is a carotenoid with antioxidant properties, commonly used as a natural food coloring. The research objective was to create calcium-crosslinked alginate films and incorporated with norbixin concentrations (N%) of 0.05%, 0.10%, and 0.50% (g norbixin/g alginate). The polymer matrix helped to retard the thermal degradation of norbixin during the drying process and decreased leaching losses during the crosslinking process. The addition of norbixin influenced film opacity in ultraviolet light (all N%) and visible light (higher N%), causing an increase in red-yellow coloration. Only the higher N% influenced the water vapor permeability of film. Norbixin thus improved the overall barrier properties of the crosslinked sodium alginate film, with a 0.50 N% showing the most promising results. When used as sunflower oil packaging, films with a N% above 0.10 provided pro-oxidant activity during storage. 相似文献
955.
Dr. Carlos Rodríguez-Nogales Dr. Didier Desmaële Dr. Víctor Sebastián Prof. Patrick Couvreur Dr. María J. Blanco-Prieto 《ChemMedChem》2021,16(24):3730-3738
Therapeutic perspectives of bone tumors such as osteosarcoma remain restricted due to the inefficacy of current treatments. We propose here the construction of a novel anticancer squalene-based nanomedicine with bone affinity and retention capacity. A squalenyl-hydroxybisphosphonate molecule was synthetized by chemical conjugation of a 1-hydroxyl-1,1-bisphosphonate moiety to the squalene chain. This amphiphilic compound was inserted onto squalenoyl-gemcitabine nanoparticles using the nanoprecipitation method. The co-assembly led to nanoconstructs of 75 nm, with different morphology and colloidal properties. The presence of squalenyl-hydroxybisphosphonate enhanced the nanoparticles binding affinity for hydroxyapatite, a mineral present in the bone. Moreover, the in vitro anticancer activity was preserved when tested in commercial and patient-treated derived pediatric osteosarcoma cells. Further in vivo studies will shed light on the potential of these nanomedicines for the treatment of bone sarcomas. 相似文献
956.
Sergii A. Sergiienko Daniela V. Lopes Gabriel Constantinescu Marta C. Ferro Nataliya D. Shchaerban Obid B. Tursunov Viacheslav I. Shkepu Hanna Pazniak Nataliya Yu. Tabachkova Enrique Rodríguez Castellón Jorge R. Frade Andrei V. Kovalevsky 《International Journal of Hydrogen Energy》2021,46(21):11636-11651
This work explores the possibilities for the processing of Ni- and Ti3C2Tx (T = OH, O) MXene-containing composite electrodes, by co-pressing and plastic deformation or by etching of the electrodes prepared directly by self-propagation high-temperature synthesis (SHS). Various material design approaches were also explored. In order to tune the Ti3C2 interlayer distance in Ti3C2Al MAX phase, an introduction of additional Al to form Ti3C2Alz materials with z > 1 was attempted. Self-propagation high-temperature synthesis of powder mixtures with extra Ni and Al content (e.g. Ni:Ti:Al:C = 1:2:3:1) resulted in SHS products containing Ti3C2Alz z > 1 material and Ni–Al alloys. Further etching of these products in 10M NaOH allowed the direct formation of electrodes with active surface containing Ti3C2Tx (T = OH, O) MXene- and Raney nickel-containing composites. The electrochemical studies were focused on hydrogen evolution and showed the potential for boosting the electrochemical reaction in Ni and MXene-containing composite electrodes, especially at high current densities. The guidelines for the processing of such electrodes under fluorine-free conditions are proposed and discussed. 相似文献
957.
Guilherme Luis Ribeiro Meirene Gandara Diego David Pinzón Moreno 《Journal of Natural Fibers》2019,16(1):13-24
Low-density polyethylene (LDPE) has caused serious environmental damages, and it has been a challenge for waste management in large cities. The LDPE recycling as composites with natural fibers such as sugarcane fibers (SCF) has been an interesting alternative to conciliate economic aspects with environmental benefits. In this study, SCF has been treated by steam explosion and incorporated to low-density polyethylene waste (LDPEW) to generate LDPEW/SCF composites with higher fiber/polymer interaction and improved mechanical properties. LDPEW/SCF composites with fibers content until 20 wt% showed mechanical properties with performance adequate for nobler applications when compared to the isolated recycled LDPEW. 相似文献
958.
Taciano D. Perez Marcelo V. Neves Diego Medaglia Pedro H. G. Monteiro César A. F. De Rose 《Software》2020,50(4):368-387
Current computer systems separate main memory from storage, and programming languages typically reflect this distinction using different representations for data in memory and storage. However, moving data back and forth between these different layers and representations compromise both programming and execution efficiency. To remedy this, the concept of orthogonal persistence (OP) was proposed in the early 1980s advocating that, from a programmer's standpoint, there should be no differences in the way that short-term and long-term data are manipulated. However, at that time, the underlying implementations still had to cope with the complexity of moving data across memory and storage. Today, recent nonvolatile memory (NVM) technologies, such as resistive RAM and phase-change memory, allow main memory and storage to be collapsed into a single layer of persistent memory, opening the way for more efficient programming abstractions for handling persistence. In this work, we revisit OP concepts in the context of NVM architectures and propose a persistent heap design for languages with automatic memory management. We demonstrate how it can significantly increase programmer and execution efficiency, removing the impedance mismatch of crossing semantic boundaries. To validate and demonstrate the presented concepts, we present JaphaVM, an implementation of the proposed design based on JamVM, an open-source Java Virtual Machine. Our results show that JaphaVM, in most cases, executes the same operations between one and two orders of magnitude faster than regular database-based and file-based implementations, while requiring significantly less lines of code. 相似文献
959.
Celia Rodríguez-Pérez Antonio Segura-Carretero María del Mar Contreras 《Critical reviews in food science and nutrition》2019,59(8):1212-1229
Prevalence of obesity worldwide has reached pandemic proportions. Despite the increasing evidence in the implication of phenolic compounds in obesity management, the real effect is not completely understood. The available in vitro and in vivo studies have demonstrated the implication of phenolic compounds in: lowering food intake, decreasing lipogenesis, increasing lipolysis, stimulating fatty acids β-oxidation, inhibiting adipocyte differentiation and growth, attenuating inflammatory responses and suppress oxidative stress. This review encompasses the most recent evidence in the anti-obesity effect of phenolic compounds from plants to different nutraceuticals and functional foods based on the in vitro, in vivo and clinical studies. For that, this review has been focused on popular plant-based products highly consumed today such as cocoa, cinnamon, and olive oil, beverages such as red wine, tea (green, white and black tea) and Hibiscus sabdariffa L. tea, among others. 相似文献
960.
Diego Sucunza Alberto J. Rico Elvira Roda María Collantes Gloria Gonzlez-Aseguinolaza Ana I. Rodríguez-Prez Ivn Peuelas Alfonso Vzquez Jos L. Labandeira-García Vania Broccoli Jos L. Lanciego 《International journal of molecular sciences》2021,22(9)
Mutations in the GBA1 gene coding for glucocerebrosidase (GCase) are the main genetic risk factor for Parkinson’s disease (PD). Indeed, identifying reduced GCase activity as a common feature underlying the typical neuropathological signatures of PD—even when considering idiopathic forms of PD—has recently paved the way for designing novel strategies focused on enhancing GCase activity to reduce alpha-synuclein burden and preventing dopaminergic cell death. Here we have performed bilateral injections of a viral vector coding for the mutated form of alpha-synuclein (rAAV9-SynA53T) for disease modeling purposes, both in mice as well as in nonhuman primates (NHPs), further inducing a progressive neuronal death in the substantia nigra pars compacta (SNpc). Next, another vector coding for the GBA1 gene (rAAV9-GBA1) was unilaterally delivered in the SNpc of mice and NHPs one month after the initial insult, together with the contralateral delivery of an empty/null rAAV9 for control purposes. Obtained results showed that GCase enhancement reduced alpha-synuclein burden, leading to improved survival of dopaminergic neurons. Data reported here support using GCase gene therapy as a disease-modifying treatment for PD and related synucleinopathies, including idiopathic forms of these disorders. 相似文献