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921.
While a few years ago the cost and availability of energy was not an important issue for the Canadian lumber industry, this situation has recently changed. Today, companies that have operated trouble-free for many years using the same technologies and practices may now have to adapt to the rising cost of fossil fuels and concerns about greenhouse gas emissions. This article addresses this problem for the particular case of the softwood lumber industry. The study describes the most important sources of energy losses in conventional drying and proposes a number of strategies and technologies to reduce kiln energy demand. 相似文献
922.
Diego Moritteo Tung-Ching Lee Michel B. Zimmermann Jeannette Nuessli Richard F. Hurrell 《Journal of food science》2005,70(5):S330-S336
ABSTRACT: Although rice can be fortified with iron by producing fortified extruded grains, achieving good sensory properties and high iron bioavailability is difficult. Our study aim was to develop iron-fortified rice with comparable sensory characteristics to natural rice using iron compounds of high bioavailability. We tested ferrous sulfate, NaFeEDTA, ferric pyrophosphate of different particle sizes (mean particle sizes: 20 (j,m, 2.5 μm, 0.5 μ-m) and electrolytic iron, as well as encapsulated forms of iron. Extruded rice grains containing 0.5 and 1 g Fe/ 100 g were produced using a single screw extruder and blended, respectively, with natural rice at a 1:100 or 1:200 ratio. Extruded rice grains were evaluated by color measurements and texture profile analysis, and iron loss during rinsing was measured. The sensory comparison between fortified and unfortified rice was performed using triangle tests. Color scores in a similar range to natural rice were obtained using ferric pyrophosphate as an iron fortification compound. The cooked extruded grains had comparable texture to cooked natural grains, and losses during rinsing were <3%. Fortification with all other compounds resulted in strong color changes. In the triangle tests, rice grains fortified with either of the 2 forms of micronized ferric pyrophosphate closely resembled unfortified rice in both uncooked and cooked form. Iron-fortified extruded rice grains with excellent sensory characteristics and potential high bioavailability can be produced using micronized ferric pyrophosphate. 相似文献
923.
Oogenesis and primordial follicle formation are tightly linked processes, requiring organized and precisely timed communication between somatic and germ cells. Deviations in ovarian cell cross talk, or aberrant gene expression within one of the cell populations, can lead to follicle loss or dysfunction, resulting in infertility. Expression of GATA-like protein-1 (GLP-1) in ovarian somatic cells is required for normal fertility in female mice, as GLP-1 deficiency leads to the absence of oocytes at birth. However, the timing and nature of this germ cell loss is not well understood. In this study, we characterize the embryonic germ cell loss in GLP-1 null mice. Quantitative PCR demonstrates that ovarian Glp-1 mRNA is expressed in a bimodal pattern during embryogenesis, peaking at E13.5-14.5 and again at birth. In contrast, adult ovaries express low but detectable levels of Glp-1 mRNA. Analysis of developing GLP-1 null mouse ovaries shows that germ cells are appropriately specified and migrate normally to nascent gonads. Upon arrival at the gonad, precocious loss of germ cells begins at around E13.5. This loss is completed by birth and is accompanied by defects in the expression of genes associated with meiotic entry. Interestingly, somatic pregranulosa cells still form basement membranes surrounding germ line cysts and express mRNA encoding paracrine signaling molecules that communicate with oocytes, albeit at lower levels than normal. Together, these data imply that the somatic cell protein GLP-1 is not necessary for many pregranulosa cell functions but is required for germ cell survival. 相似文献
924.
Diego Galvan Luciane Effting Luiz Torres Neto Carlos Adam Conte-Junior 《Comprehensive Reviews in Food Science and Food Safety》2021,20(4):3136-3163
Essential oils (EOs) are commercially important products, sources of compounds with antioxidant and antimicrobial activities considered indispensable for several fields, such as the food industry, cosmetics, perfumes, pharmaceuticals, sanitary and agricultural industries. In this context, this systematic review and meta-analysis, a novel approach will be presented using chemometric tools to verify and recognize patterns of antioxidant, antibacterial, and antifungal activities of EOs according to their geographic, botanical, chemical, and microbiological distribution. Scientific papers were selected following the Preferred Reporting Items for Systematic Review and Meta-Analyses statement flow diagram, and the data were evaluated by the self-organizing map and hierarchical cluster analysis. Overall, this novel approach allowed us to draw an overview of antioxidants and antimicrobials activities of EOs reported in 2019, through 585 articles evaluated, obtaining a dataset with more than 10,000 data, distributed in more than 80 countries, 290 plant genera, 150 chemical compounds, 30 genera of bacteria, and 10 genera of fungi. The networks for geographic, botanical, chemical, and microbiological distribution indicated that Brazil, Asia, the botanical genus Thymus, species Thymus vulgaris L. “thyme,” the Lamiaceae family, limonene, and the oxygenated monoterpene class were the most representative in the dataset, while the species Escherichia coli and Candida albicans were the most used to assess the antimicrobial activity of EOs. This work can be seen as a guide for the processing of metadata using a novel approach with non-conventional statistical methods. However, this preliminary approach with EOs can be extended to other sources or areas of food science. 相似文献
925.
Rodriguez-Gutiez Eduardo Moreton-Fernandez Ana Gonzalez-Escribano Arturo Llanos Diego R. 《The Journal of supercomputing》2019,75(11):7101-7124
The Journal of Supercomputing - Scientific applications are some of the most computationally demanding software pieces. Their core is usually a set of linear algebra operations, which may represent... 相似文献
926.
Diego Úbeda Francisco J. PinarPablo Cañizares Manuel A. RodrigoJusto Lobato 《International Journal of Hydrogen Energy》2012
Fuel cells are a very complex system in which many phenomena of different nature occur simultaneously and within a small space, so a truthful measurement of some variables is not feasible using state-of-the-art technology. If a deep knowledge of the unit is desired, modeling can be of great help when it is properly used as it is possible to calculate the value of the variables of interest by adjusting experimental data. However, when models are complicated, it is not trivial to identify in which way a certain parameter alters the model results and then it is necessary to resort to sensitivity analysis before approaching an adequate parameter estimation procedure. In this work, a parameter estimation procedure has been proposed with the results obtained from the sensitivity analysis applied to a high temperature proton exchange membrane fuel cell (HT-PEMFC) model. The procedure has been demonstrated to be straightforwardly applicable as well as effective, which makes it suitable to be used as engineering tool to obtain a first consistent value of the parameters that define the main characteristics of a HT-PEMFC. 相似文献
927.
Ivan Gonzalez Sergio Lopez-Buedo Gustavo Sutter Diego Sanchez-Roman Francisco J. Gomez-Arribas Javier Aracil 《Journal of Systems Architecture》2012,58(6-7):247-256
HPRC (High-Performance Reconfigurable Computing) systems include multicore processors and reconfigurable devices acting as custom coprocessors. Due to economic constraints, the number of reconfigurable devices is usually smaller than the number of processor cores, thus preventing that a 1:1 mapping between cores and coprocessors could be achieved. This paper presents a solution to this problem, based on the virtualization of reconfigurable coprocessors. A Virtual Coprocessor Monitor (VCM) has been devised for the XtremeData XD2000i In-Socket Accelerator, and a thread-safe API is available for user applications to communicate with the VCM. Two reference applications, an IDEA cipher and an Euler CFD solver, have been implemented in order to validate the proposed architecture and execution model. Results show that the benefits arising from coprocessor virtualization outperform its overhead, specially when code has a significant software weight. 相似文献
928.
Davide Comboni Francesco Pagliaro G. Diego Gatta Paolo Lotti Sula Milani Marco Merlini Tommaso Battiston Konstantin Glazyrin Hanns-Peter Liermann 《Journal of the American Ceramic Society》2020,103(9):5291-5301
The high-pressure behavior of kernite [ideally Na2B4O6(OH)2·3H2O, a ~ 7.02 Å, b ~ 9.16 Å, c ~ 15.68 Å, β = 108.9°, Sp Gr P21/c, at ambient conditions], an important B-bearing raw material (with B2O3 ≈ 51 wt%) and a potential B-rich aggregate in radiation shielding materials, has been studied by single-crystal synchrotron X-ray diffraction up to 14.6 GPa. Kernite undergoes an iso-symmetric phase transition at 1.6-2.0 GPa (to kernite-II). Between 6.6-7.5 GPa, kernite undergoes a second phase transition, possibly iso-symmetric in character (to kernite-III). The crystal structure of kernite-II was solved and refined. The isothermal bulk modulus (KV0 = β-1P0,T0, where βP0,T0 is the volume compressibility coefficient) of the ambient-pressure polymorph of kernite was found to be KV0 = 29(1) GPa and a marked anisotropic compressional pattern, with K(a)0: K(b)0: K(c)0~1:3:1.5., was observed. In kernite-II, the KV0 increases to 43.3(9) GPa and the anisotropic compressional pattern increases pronouncedly. The mechanisms, at the atomic scale, which govern the structure deformation, have been described. 相似文献
929.
930.
Andrea Lavorato Stefania Raimondo Marina Boido Luisa Muratori Giorgia Durante Fabio Cofano Francesca Vincitorio Salvatore Petrone Paolo Titolo Fulvio Tartara Alessandro Vercelli Diego Garbossa 《International journal of molecular sciences》2021,22(2)
Traumatic peripheral nerve lesions affect hundreds of thousands of patients every year; their consequences are life-altering and often devastating and cause alterations in movement and sensitivity. Spontaneous peripheral nerve recovery is often inadequate. In this context, nowadays, cell therapy represents one of the most innovative approaches in the field of nerve repair therapies. The purpose of this systematic review is to discuss the features of different types of mesenchymal stem cells (MSCs) relevant for peripheral nerve regeneration after nerve injury. The published literature was reviewed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A combination of the keywords “nerve regeneration”, “stem cells”, “peripheral nerve injury”, “rat”, and “human” were used. Additionally, a “MeSH” research was performed in PubMed using the terms “stem cells” and “nerve regeneration”. The characteristics of the most widely used MSCs, their paracrine potential, targeted stimulation, and differentiation potentials into Schwann-like and neuronal-like cells are described in this paper. Considering their ability to support and stimulate axonal growth, their remarkable paracrine activity, their presumed differentiation potential, their extremely low immunogenicity, and their high survival rate after transplantation, ADSCs appear to be the most suitable and promising MSCs for the recovery of peripheral nerve lesion. Clinical considerations are finally reported. 相似文献