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11.
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2013 are reviewed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
12.
Milk production and dry matter intake of 21 cows subjected to 16 h of fluorescent light and 8 h dark and of 21 cows subjected to natural light 9 to 12 h daily between October 25 and March 14 were measured beginning in early (37 to 74 days postpartum) and late (94 to 204 days postpartum) lactation. Cows that received 16 h of fluorescent light produced 6.7% (1.4 kg) more milk per day (adjusted for parity and pretreatment production) than cows exposed to natural photoperiods. Increases of milk production with 16 h of fluorescent light were similar for early and late lactation. Photoperiod did not alter percent of fat in milk. Dry matter intake increased 6.1% for cows in 16 h of light, and this increase could account for increased milk yields. Basal prolactin in serum and that released by thyrotropin releasing hormone were 1.5 to 1.8 times greater for cows exposed to 16 h of light than for cows in 9 to 12 h of natural light daily. Photoperiod did not affect release of prolactin by milking. Cold ambient temperatures reduced basal prolactin and prolactin released by thyrotropin releasing hormone but had no effect on concentrations of growth hormone or glucocorticoids. Compared with cows in late lactation, cows in early lactation released 2.4 times more prolactin after milking, but they released similar amounts of prolactin after thyrotropin releasing hormone. Photoperiod did not affect concentrations of growth hormone or glucocorticoids in blood sera.  相似文献   
13.
Scanned, single-channel optical heterodyne detection has been used in a variety of lidar applications from ranging and velocity measurements to differential absorption spectroscopy. We describe the design of a coherent camera system that is based on a two-dimensional staring array of heterodyne receivers for coherent imaging applications. Experimental results with a single HgCdTe detector translated in the image plane to form a synthetic two-dimensional array demonstrate the ability to obtain passive heterodyne images of chemical vapor plumes that are invisible to normal video infrared cameras. We describe active heterodyne imaging experiments with use of focal-plane arrays that yield hard-body Doppler lidar images and also demonstrate spatial averaging to reduce speckle effects in static coherent images.  相似文献   
14.
Although the nonlactating period presents a risk for intramammary infection, efficient systems to monitor infection status of recently calved cows have not been developed, and benchmarks for interpretation have not been established. Individual cow somatic cell count (SCC) data for the current and previous six monthly Dairy Herd Improvement milk tests and the last SCC of the previous lactation and first SCC of the current lactation were summarized for all milking cows in a selection of Wisconsin dairy herds. Prevalence of infection, herd new infection rate, fresh cow contribution to herd new infection rate, dry cow new infection rate, heifer new infection rate, and dry cow cure rate were estimated using a threshold of 200,000/ml. In 145 herds, mean (range) heifer new infection rate was 21.3% (0 to 58%). The cut-point for the 10th percentile of herds was 8%. Mean (range) dry cow new infection rate in cows that were uninfected at the last test before dry off was 22.4% (0 to 71%), and the cut-point for the 10th percentile of herds was 9%. Although nonlactating cow and heifer new infection rates increased with weighted 6-mo mean herd SCC, the between-herd variation was large, suggesting that on-farm factors are important in determining the rates of infection. In a subset of 51 Wisconsin dairy herds, significant monthly variation in weighted SCC, prevalence, herd new infection rate, and fresh cow contribution to herd new infection rate were detected. Elevations in SCC and prevalence of infection during the summer (July through September) were associated with significant increases in fresh cow and herd new infection rates.  相似文献   
15.
鲜食大豆的品质指标包括外观品质、营养品质、食味品质、卫生品质。衡量食味的主要品质指标有甜味、质地、香味和鲜味等。研究表明鲜食大豆的甜味与其籽粒的蔗糖含量呈显著正相关;可用籽粒的硬度表示质地;鲜食大豆的鲜味品质主要是由鲜食大豆的游离氨基酸含量决定的,可用天冬氨酸和谷氨酸的含量作为评价的客观指标。研究还表明了鲜食大豆的营养与食味品质问存在着一定的矛盾,大豆蛋白质的含量与其籽粒硬度呈显著正相关。  相似文献   
16.
IDH (isocitrate dehydrogenase) mutation, hypoxia, and neo-angiogenesis, three hallmarks of diffuse gliomas, modulate the expression of small non-coding RNAs (miRNA). In this paper, we tested whether pro-angiogenic and/or pro-hypoxic miRNAs could be used to monitor patients with glioma. The miRNAs were extracted from tumoral surgical specimens embedded in the paraffin of 97 patients with diffuse gliomas and, for 7 patients, from a blood sample too. The expression of 10 pro-angiogenic and/or pro-hypoxic miRNAs was assayed by qRT-PCR and normalized to the miRNA expression of non-tumoral brain tissues. We confirmed in vitro that IDH in hypoxia (1% O2, 24 h) alters pro-angiogenic and/or pro-hypoxic miRNA expression in HBT-14 (U-87 MG) cells. Then, we reported that the expression of these miRNAs is (i) strongly affected in patients with glioma compared to that in a non-tumoral brain; (ii) correlated with the histology/grade of glioma according to the 2016 WHO classification; and (iii) predicts the overall and/or progression-free survival of patients with glioma in univariate but not in a multivariate analysis after adjusting for sex, age at diagnosis, and WHO classification. Finally, the expression of miRNAs was found to be the same between the plasma and glial tumor of the same patient. This study highlights a panel of seven pro-angiogenic and/or pro-hypoxic miRNAs as a potential tool for monitoring patients with glioma.  相似文献   
17.
18.
We review a series of experiments that have established that super-oxygenated La2−x Sr x CuO4+y phase-separates at low temperature into large magnetic and superconducting regions, driven by the physics of the doped holes themselves. Magnetization studies of trapped flux indicate that the large phase-separated magnetic and superconducting regions develop from nanoscale regions of charge inhomogeneity present in Sr-doped La2CuO4 and other more commonly studied cuprates. Neutron studies of the elastic magnetic diffraction show that the peak intensity grows with applied field as in La2−x Sr x CuO4. However, the magnitude of the increase varies widely and is not well accounted for by current theory.  相似文献   
19.
This paper presents a novel dual-current pump module (DCPM) to improve the transient response of dc-dc converters. The DCPM operates only during transient to provide two additional current injections for step-up load and current drains for step-down load. Due to the two current pump paths, the current stress on the switches of the DCPM is also reduced. The measurement results show that the DCPM can enhance the dynamic recovery time of the buck dc-dc converter by more than an order.  相似文献   
20.
The ocean surface velocity field in the Cape Blanc region, off Northwest Africa, is investigated with the maximum cross-correlation (MCC) method applied to channel-4 Advanced Very High Resolution Radiometer satellite images. An initial sensitivity analysis allows us to select the four parameters that provide maximum area coverage and the best velocity resolution, while limiting the standard deviation for each velocity component within reasonable values. These are (m, n, MV, CT)?=?(22, 32, 50, 0.6), where m and n are the number of pixels of the search window (SW) and reference window (RW), respectively, MV is the maximum possible velocity (in cm s?1), and CT is a correlation threshold for a feature to be tracked. A total of 489 images, for years 2005 and 2006, are analysed, and 106 velocity maps are generated with good coverage of the coastal transition zone (CTZ), most of them for the winter (34) and spring (59) seasons. We remove spurious data using the method's own filters (MV, CT, and a neighbour-vector comparison), requesting the velocity components to have Gaussian distributions and smoothing the resulting velocity fields with a median-vector filter. The instantaneous velocity maps illustrate the response of the alongshore coastal jet north of Cape Blanc (and its extension along the Cape Verde frontal region) to wind forcing, as well as the presence of numerous mesoscalar features (100–300 km wide) superposed on a westward offshore transport south of Cape Blanc. We also produce mean and standard deviation winter and spring velocity maps, which are compared with the corresponding mean sea surface temperature fields. The along-shore and offshore flow is better defined and is more intense in spring than in winter, in concordance with cross-slope sharper temperature gradients during this season, and brings about a cooling of the whole region. We identify five different ubiquitous currents: a southwestward jet north of Cape Blanc, a northwestward jet off Banc d'Argin, an offshore convergent jet, a spring jet-like feature at 18° N, and a southward flow in the southwestern CTZ.  相似文献   
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