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941.
Janaína Capelli‐Peixoto Simon Ngao Mule Fabia Tomie Tano Giuseppe Palmisano Beatriz Simonsen Stolf 《Proteomics. Clinical applications》2019,13(6)
Leishmaniases are diseases caused by protozoan parasites of the genus Leishmania. They are endemic in 98 countries, affect around 12 million people worldwide and may present several distinct clinical forms. Unfortunately, there are only a few drugs available for treatment of leishmaniasis, which are toxic and not always effective. Different parasite species and different clinical forms require optimization of the treatment or more specific therapies, which are not available. The emergence of resistance is also a matter of concern. Besides, diagnosis can sometimes be complicated due to atypical manifestations and associations with other pathologies. In this review, proteomic data are presented and discussed in terms of their application in important issues in leishmaniasis such as parasite resistance to chemotherapy, diagnosis of active disease in patients and dogs, markers for different clinical forms, identification of virulence factors, and their potential use in vaccination. It is shown that proteomics has contributed to the discovery of potential biomarkers for prognosis, diagnosis, therapeutics, monitoring of disease progression, treatment follow‐up and identification of vaccine candidates for specific diseases. However, the authors believe its capabilities have not yet been fully explored for routine clinical analysis for several reasons, which will be presented in this review. 相似文献
942.
Determination of percolation threshold and electrical conductivity of polyvinylidene fluoride (PVDF)/short carbon fiber (SCF) composites: effect of SCF aspect ratio 下载免费PDF全文
Ranvijai Ram Mostafizur Rahaman Ali Aldalbahi Dipak Khastgir 《Polymer International》2017,66(4):573-582
Composites of polyvinylidene fluoride (PVDF) and short carbon fibers (SCFs) with different aspect ratios of the SCFs were prepared by the solution casting technique. The electrical percolation thresholds of the composites are highly influenced by the SCF aspect ratio calculated using both the Sigmoidal Boltzmann model and classical percolation theory. It was observed that the percolation threshold of PVDF/SCF composites decreases with an increase in the aspect ratio of the SCFs in the PVDF matrix. Different theoretical models were used to check the alignment of the SCFs in the PVDF matrix. The applicability of the theoretical models was tested to predict the composition‐dependent electrical conductivity at different SCF loadings and aspect ratios and the predictions were compared with experimental results. The effect of the fiber aspect ratio on the AC electrical conductivity was also investigated. Finally, the transparency of the composites was tested with the help of UV?visible spectroscopy and exhibits an SCF loading dependence in the PVDF matrix. © 2016 Society of Chemical Industry 相似文献
943.
Beatriz Otero Eva Rodríguez Otilio Rojas Javier Verdú Juan José Costa Manuel Alejandro Pajuelo Ramón Canal 《International Journal of Network Management》2021,31(4):e2137
Freelance, part-time, work-at-home, and other flexible jobs are changing the concept of workplace and bringing information and content exchange problems to companies. Geographically, spread corporations may use remote distribution of software and data to attend employees' demands, by exploiting emerging delivery technologies. In this context, cost-efficient software distribution is crucial to allow business evolution and make IT infrastructures more agile. On the other hand, container-based virtualization technology is shaping the new trends of software deployment and infrastructure design. We envision current and future enterprise IT management trends evolving towards container-based software delivery over hybrid content delivery networks (CDNs). This paper presents a novel cost-efficient QoS-aware analytical model and a hybrid CDN–peer-to-peer (P2P) architecture for enterprise software distribution. The model would allow delivery cost minimization for a wide range of companies, from big multinationals to SMEs, using CDN–P2P distribution under various industrial hypothetical scenarios. Model constraints guarantee acceptable deployment times and keep interchanged content amounts below the bandwidth and storage network limits in our scenarios. Indeed, key model parameters account for network bandwidth, storage limits, and rental prices, which are empirically determined from their offered values by the commercial delivery networks KeyCDN, MaxCDN, CDN77, and BunnyCDN. This preliminary study indicates that MaxCDN offers the best cost-QoS trade-off. The model is implemented in the network simulation tool PeerSim and then applied to diverse testing scenarios by varying company types, number and profile (either, technical or administrative) of employees, and the number and size of content requests. Hybrid simulation results show overall economic savings between 5% and 20%, compared to just hiring resources from a commercial CDN, while guaranteeing satisfactory QoS levels in terms of deployment times and number of served requests. 相似文献
944.
Beatriz dos Santos Pês Janaina Gonçalves Guimarães Marlio José do Couto Bonfim 《Journal of Computational Electronics》2017,16(1):98-105
Spiking neural networks (SNNs) first came to the attention of scientists due to the search for a structure capable of emulating more closely the behavior of the human brain. The biological nervous system has some characteristics that allow it to process a large amount of data very quickly. It is also a fault-tolerant system, with a high level of parallelism. Low power consumption is another feature of the human brain that is desirable for electronic circuits. In this context, several models of artificial spiking neurons were developed, aiming to construct networks able to combine the best characteristics of the human brain. Most of these models, however, lack validation in larger networks. This paper proposes the implementation of an SNN based on a nanoelectronic spiking neuron model developed in previous works. To validate the behavior of an isolated neuron in a network, logic gates (NOT, OR, AND, and XOR) are used as a benchmark. The goal of this paper is to present a feasibility study on the possibility of implementing such nanoelectronic spiking neuron networks based on this spiking neuron model. Nanoelectronics represents an appealing implementation due to the gains regarding occupied area and power consumption, which are inherent characteristics of this technology. The neuron model was modified for simulation at room temperature. An information code based on the amplitude of the pulses presented at the output of the neuron was developed. During deployment of this approach, some limitations regarding the neuron model were detected; some possible solutions are proposed as future work. 相似文献
945.
Bhagwan Ram Raad Dheeraj Sharma Kaushal Nigam Pravin Kondekar 《Journal of Computational Electronics》2017,16(1):24-29
A distinct materials combination is presented for tunnel field-effect transistors (TFETs): gallium arsenide phosphide (GaAsP) as a wider-bandgap material in the drain and channel regions with indium gallium arsenide (InGaAs) as a narrow-bandgap material for the source region. The introduction of this novel materials combination greatly improves the ON-state current, OFF-state current, ambipolar behavior, threshold voltage, and subthreshold slope compared with other group III–V ternary heterojunction TFETs. In GaAsP–InGaAs TFETs, the ambipolar current remains equal to the OFF-state current. This paper explores the potential of the proposed device for ultralow-power high-performance applications. 相似文献
946.
Rodrigo Barbosa Acioli OliveiraWarlley Pinheiro Evangelista Maria José SenaMaria Beatriz Abreu Gloria 《Food Control》2012,25(1):64-68
The objective of this study was to investigate existing fishing, capture and post-capture practices and their effects on the quality of tuna with respect to histamine and other amines. The study was undertaken in the northeastern coast of Brazil from December 2007 until December 2008. Fishing was performed at high-ocean by pelagic trawl using stainless steel boats and Spanish or American technology. Illex argentinus was used as baits. The fish were insensibilized, bled, eviscerated, rinsed with seawater and stored with flake ice. Histamine was not detected in 95% of the samples whereas histamine levels ranged from 4.92 to 6.90 mg/kg in 5% of the samples. Every lot analyzed complied with the European legislation, and the fish were classified as good quality. No significant difference was observed on histamine levels between fish that were captured dead and alive. The results indicate that the prevalent fishing, capture and post-capture practices used by boats from Rio Grande do Norte, Brazil, are ensuring good quality tuna. 相似文献
947.
Eduardo Medina Ana Morales‐Sillero Eva Mª Ramírez Pilar Rallo Manuel Brenes Concepción Romero 《International Journal of Food Science & Technology》2012,47(11):2334-2341
New table olive genotypes (48) coming from a cross‐breeding programme were evaluated. Most of the fruit traits covered a wide range of variability on the set of genotypes, fruit weight (1.1–9.7 g), pulp‐to‐pit ratio (1.7–10.0), fruit shape (1.0–1.6) and oil content (1.3–15.2%). This is the first time that healthy compounds such as triterpenic acids and phenolic compounds have also been evaluated in olive progenies. Genotypes were stored for 2 months in sterilised brine (5% NaCl and 0.5% acetic acid). A high amount of maslinic (685.0–1394.2 mg kg?1 olive flesh) and oleanolic acids (275.3–817.9 mg kg?1 olive flesh) was found in the flesh of olives stored. The main oleosidic and phenolic compounds evaluated in brines were hydroxytyrosol (1.9–8.4 mmol L?1), hydroxytyrosol glucosides (0.4–19.8 mmol L?1), oleuropein (0.0–4.7 mmol L?1) and the antimicrobial compounds, dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol (0.0–3.4 mmol L?1) and decarboxymethyl elenolic acid (0.0–1.7 mmol L?1), the latter two being observed in only ten genotypes. The wide range of variation observed for most compounds indicates that the contents of these healthy compounds may be used as selection criteria in table olive breeding programmes. 相似文献
948.
Effect of virgin coconut oil cake on physical,textural, microbial and sensory attributes of muffins 下载免费PDF全文
Shameena Beegum Monika Sharma Musuvadi Ramarathinam Manikantan Ram Kishor Gupta 《International Journal of Food Science & Technology》2017,52(2):540-549
A study was carried out to develop muffins by substituting refined wheat flour (RWF) with virgin coconut oil (VCO) cake (0–50 g/100 g flour blend). Progressive replacement of RWF with VCO cake resulted in significant (P < 0.05) decrease in peak viscosity of flour blends (from 2527.75 cP in the control to 389.5 cP in 50 g VCO cake/100 g flour blend) and the muffins height (from 34.26 mm in the control to 26.88 mm in 50 g VCO cake/100 g flour blend). Significant colour change was observed in the crust and crumb regions. Free fatty acid and microbial analysis revealed that the quality of muffin samples was unaffected by the addition of VCO cake during 16‐day storage at both refrigerated (4 ± 2 °C) and ambient temperature (35 ± 2 °C). Incorporation of 40 g VCO cake/100 g flour blend significantly (P < 0.05) increased the overall acceptability of the muffins (with a maximum score of 8.5). Muffins with 40 g VCO cake/100 g flour blend were enriched with protein (8.49 g/100 g), fat (18.46 g/100 g), crude fibre (1.14 g/100 g) and minerals (1.15 g/100 g). 相似文献
949.
Consolación Melguizo Jose Prados Raquel Luque Raúl Ortiz Octavio Caba Pablo J. álvarez Beatriz Gonzalez Antonia Aranega 《International journal of molecular sciences》2012,13(12):16624-16635
Carboplatin-paclitaxel is a reference regimen in the treatment of locally advanced or disseminated non-small cell lung cancer (NSCLC). This paper discusses the multidrug resistance developed with this drug combination, which is one of the major obstacles to successful treatment. In order to understand and overcome the drug resistance pattern of NSCLC after carboplatin plus paclitaxel exposure, levels of mRNA expression of multidrug resistance 1 (MDR1) and multidrug resistance-associated protein 3 (MRP3) were investigated in primary NSCLC cell lines (A-549 and A-427) and a metastasis-derived NSCLC cell line (NODO). Our results showed that exposure of the three NSCLC lines to plasma concentrations of paclitaxel (5 μM) produced an increase in MDR1 expression, while MRP3 showed no alteration in expression. By contrast, the same cells exposed to carboplatin plasma concentrations (30 μM) showed overexpression of MRP3. In these cells, MDR1 showed no expression changes. Interestingly, the combination of both paclitaxel and carboplatin caused increased expression of the MDR1 drug resistance gene rather than the individual treatments. These results suggest that carboplatin and paclitaxel may induce drug resistance mediated by MDR1 and MRP3, which may be enhanced by the simultaneous use of both drugs. 相似文献
950.
Reeba Panesar Parmjit S. Panesar Ram S. Singh John F. Kennedy 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(1):42-46
BACKGROUND: Hydrolysis of lactose with β‐D‐galactosidase is one of the most promising biotechnological applications in the food industry because of its use in the production of low lactose milk products and whey hydrolysis. To overcome the problem of enzyme extraction from cells due to the intracellular nature of β‐D‐galactosidase and the poor permeability of the cell membrane to lactose, permeabilization of yeast cells was investigated. Permeabilized whole cells have been claimed to have an advantage over more pure enzyme preparations. In view of the advantages of immobilized cell systems over free cell systems, permeabilized cells were immobilized by an entrapment method in calcium alginate gel. A packed bed reactor together with this immobilized cell system has been used for hydrolysis of milk lactose in a continuous system. RESULTS: Different process parameters (temperature, substrate feed rate, biomass load and time‐course) were optimized to maximize lactose hydrolysis. The immobilized yeast cells (300 mg dry wt) resulted in 87.2% hydrolysis of milk lactose at 30 °C and flow rate 7 mL h?1 in a packed bed reactor system. CONCLUSION: This convenient and relatively inexpensive method of immobilization, resulting in high hydrolysis potential in a continuous system, indicates that permeabilized yeast cells have the potential for the production of low lactose milk and milk products. Copyright © 2010 Society of Chemical Industry 相似文献