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排序方式: 共有843条查询结果,搜索用时 46 毫秒
111.
Subjected 86 3-day-old White Leghorn chicks, reared either socially or in isolation in large or small boxes, to tonic immobility by a ventral restraint induction procedure. Test boxes were identical to rearing boxes or differed only in size. Incidence and duration of immobility were reliably enhanced by social and high-density rearing, but similarity of test and rearing boxes had no effect. A high negative correlation between vocalization rate and duration of eye closure was obtained. Results are discussed in terms of the optimizing induction procedure in relation to early righting behavior. Qualitatively different stages of immobility are defined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
G Zoppi A Luciano M Cinquetti S Graziani M Bolognani 《Canadian Metallurgical Quarterly》1998,52(5):360-362
Over the period of a year I have systematically recorded any episodes of continuing medical education (CME) that I have attended, and reflect on the effectiveness of this system in terms of whether it has achieved its objective, that is, has my behaviour changed, and whether the existence of the need to record CME has influenced this effect. I consider which aspects of CME have been most beneficial. I conclude that the proposed level of CME is readily achievable, useful, but costly. The way in which I learn most or best is in preparing presentations or teaching sessions. There has been some debate on the usefulness of keeping a record of CME to which I would like to add my opinion. I also recommend the form of record keeping I have used as an impetus to reflection and research on the topic of education received, as this reinforces and enhances the educational experience. 相似文献
113.
Luciano M. Bezerra Sunil Saigal 《International journal for numerical methods in engineering》1993,36(13):2189-2202
A boundary integral formulation is presented for the detection of flaws in planar structural members from the displacement measurements given at some boundary locations and the applied loading. Such inverse problems usually start with an initial guess for the flaw location and size and proceed towards the final configuration in a sequence of iterative steps. A finite element formulation will require a remeshing of the object corresponding to the revised flaw configuration in each iteration making the procedure computationally expensive and cumbersome. No such remeshing is required for the boundary element approach. The inverse problem is written as an optimization problem with the objective function being the sum of the squares of the differences between the measured displacements and the computed displacements for the assumed flaw configuration. The geometric condition that the flaw lies within the domain of the object is imposed using the internal penalty function approach in which the objective function is augmented by the constraint using a penalty parameter. A first-order regularization procedure is also implemented to modify the objective function in order to minimize the numerical fluctuations that may be caused in the numerical procedure due to errors in the experimental measurements for displacements. The flaw configuration is defined in terms of geometric parameters and the sensitivities with respect to these parameters are obtained in the boundary element framework using the implicit differentiation approach. A series of numerical examples involving the detection of circular and elliptical flaws of various sizes and orientations are solved using the present approach. Good predictions of the flaw shape and location are obtained. 相似文献
114.
Impact of diet supplemented with microencapsulated condensed tannins on cow milk nutritional profile
Attilio Matera Lucia Sepe Silvia Vincenzetti Roberta Tolve Nicola Condelli Salvatore Claps Francesco Genovese Annamaria Ricciardi Teresa Zotta Teresa Scarpa Maria Antonietta Di Napoli Giulia Francesca Cifuni Paolo Polidori Giuseppe Santini Luciano Scarano Giuseppe Altieri Giovanni Carlo Di Renzo Sofia Renzi Marilisa Giavalisco Fernanda Galgano 《International Journal of Dairy Technology》2023,76(4):813-827
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock. 相似文献
115.
Nasim Mia Kuljeet Singh James Polson Luciano Lisi Evan Willemsen Yulin Hu 《加拿大化工杂志》2024,102(2):585-606
Hydrogen (H2) is a clean energy carrier widely used in oil refineries, fertilizers, chemicals, and steel manufacturing. Presently, the majority of H2 is produced from either steam methane reforming of natural gas or coal gasification; however, these technologies result in a massive amount of CO2 emission. Alternatively, the use of photocatalysts for producing H2 via water splitting is an eco-friendly and sustainable approach, among which the selection of highly efficient, stable, and cheap photocatalysts is the key. In this review, Znln2S4-based photocatalysts are thoroughly described in terms of the fundamentals and thermodynamics of water splitting, fabrication methods, and different heterostructure photocatalytic systems. After this, recent developments in the large-scale implementation of photocatalytic reactors are discussed. Finally, a summary of future research directions and major conclusions is provided. With proper modification, such as heterojunction systems and the selection of proper fabrication methods, Znln2S4-based photocatalysts could be superior materials for water splitting. In short, this review article could offer meaningful and useful insights and guidance for the development of Znln2S4-based photocatalysts in water splitting for producing H2 under visible light. 相似文献
116.
Bruna A. Kamimura Marciane Magnani Winnie A. Luciano Fernanda B. Campagnollo Tatiana C. Pimentel Vernica O. Alvarenga Beatriz O. Pelegrino Adriano G. Cruz Anderson S. Sant'Ana 《Comprehensive Reviews in Food Science and Food Safety》2019,18(5):1636-1657
A large variety of cheeses exist in Brazil, reflecting historical and cultural aspects. Brazilian artisanal cheeses present differences in the processing, ripening time (when applied), type of milk used, texture, size, shape, color, moisture content, flavor, the use or not of starter cultures, among others. This review describes the main artisanal cheeses produced in Brazil, focusing on general and particular characteristics associated with their making process and geographical identity. Overall, the high variability of the physicochemical data and deficiency of information on sensorial properties of Brazilian artisanal cheeses were noticed. On the other hand, culture‐dependent methods were mostly used to expand the knowledge into the microbiology of these cheeses, whereas their microbial diversity has been recently discovered through the use of 16S rRNA gene sequencing‐based methods. The certification of a geographical indication for Brazilian artisanal cheeses may encompass an essential milestone for adding value to these products. Regardless of their significance in the diet, culture, and economy of producing regions, taken together, the reviewed literature discloses the need of insightful studies to generate scientific data to support the expansion of the market, while ensuring the protection of historic aspects related to the production of Brazilian artisanal cheeses. 相似文献
117.
Cátia L. Ücker Luciano T. Gularte Cristian D. Fernandes Vitor Goetzke Eduardo Ceretta Moreira Cristiane W. Raubach Mario L. Moreira Sergio S. Cava 《Journal of the American Ceramic Society》2019,102(4):1884-1892
This work demonstrates the obtention of Nb2O5 nanoparticles by the microwave-assisted hydrothermal synthesis method in a fast way and with the use of low temperatures. The heat treatment applied on the samples promotes the phase change in Nb2O5 from pseudohexagonal to orthorhombic as the temperature increases, with a particle size between 7.3 and 32.6 nm. The band gap of the samples decreases with increasing temperature, obtaining a minimum value of 3.04 eV at 800°C. Dye-sensitized solar cells (DSSC) were assembled using the Doctor Blade coating technique. The photovoltaic parameters of open-circuit voltage (Voc) and short-circuit current density (Jsc) were evaluated. The cells showed a photovoltaic response, demonstrating that Nb2O5 has a semiconductive potential. The DSSC have different characteristics regarding Jsc and Voc, showing that according to the temperature increase in the semiconductor sample, there is a decrease in the photovoltaic parameters of the cells. 相似文献
118.
A novel carbon paste electrode containing chitosan microspheres for the determination of Cu(II) in instant coffee by anodic stripping voltammetry was developed. Chitosan was crosslinked with the chelating agent 8-hydroxyquinoline-5-sulphonic acid and glutaraldehyde. The microspheres of the crosslinked chitosan biopolymer were obtained by the spray drying technique and employed in the construction of the sensor. In acetate buffer solution (0.1 mol L−1, pH 6.0), the calibration curve obtained was linear for concentrations of 5.0 × 10−7 to 1.4 × 10−5 mol L−1 (r = 0.9990); the detection limit was 5.5 × 10−8 mol L−1. The relative standard deviation (n = 8) was lower than 3.0% for solutions containing 6.0 × 10−6, 5.0 × 10−5 and 1.5 × 10−4 mol L−1 of Cu(II). The method was successfully employed for determination of Cu(II) in instant coffee and the results obtained showed good agreement when compared with those using electrothermal atomic absorption spectrometry. 相似文献
119.
120.
This paper presents an approach for evaluating collaboration attributes in companies operating in industrial clusters. From the literature review, we identified governance, geographic proximity, and trust as the main collaboration attributes in industrial clusters. For each of them, there is a set of related sub-attributes that composed the evaluation model. For developing the model, we used the graph theoretic approach (GTA), a methodology for multi-attribute assessment that considers interdependencies among elements of a system to provide an overall evaluation. We applied the model to five companies of a furniture cluster. The results showed the model allows for systematizing relationship management because it highlights the collaboration attributes that need to be improved. Furthermore, the application of the model may contribute to encouraging companies to develop collaborative practices. 相似文献