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1.
The spinal ejaculation generator (SEG) is located in the central gray (lamina X) of the rat lumbar spinal cord and plays a pivotal role in the ejaculatory reflex. We recently reported that SEG neurons express the oxytocin receptor and are activated by oxytocin projections from the paraventricular nucleus of hypothalamus (PVH). However, it is unknown whether the SEG responds to oxytocin in vivo. In this study, we analyzed the characteristics of the brain–spinal cord neural circuit that controls male sexual function using a newly developed in vivo electrophysiological technique. Optogenetic stimulation of the PVH of rats expressing channel rhodopsin under the oxytocin receptor promoter increased the spontaneous firing of most lamina X SEG neurons. This is the first demonstration of the in vivo electrical response from the deeper (lamina X) neurons in the spinal cord. Furthermore, we succeeded in the in vivo whole-cell recordings of lamina X neurons. In vivo whole-cell recordings may reveal the features of lamina X SEG neurons, including differences in neurotransmitters and response to stimulation. Taken together, these results suggest that in vivo electrophysiological stimulation can elucidate the neurophysiological response of a variety of spinal neurons during male sexual behavior.  相似文献   
2.
在广电总局和省局指示精神的指导下,江苏有线三网融合枢纽中心建成了省中心集中汇聚,分中心独立管控的三级安播监管体系。本文从建设目标,网络结构,系统组成等方面介绍了江苏有线安播监管系统,提出了“播监控三维一体”,“省市县三位一体”的省级全覆盖式安播监管体系解决方案。  相似文献   
3.
苯甲醛、尿素和乙酰乙酸乙酯三组分“一锅煮”可以同时制备Biginelli和Hantzsch两种产物。教学中通过改变催化剂种类、反应物料比、反应溶剂等条件,引导学生探讨反应条件的改变对总产率及两种异构体比例的影响。实验中通过薄层色谱来跟踪反应进程,通过柱色谱分离混合物,最后通过熔点、红外光谱对合成的化合物进行结构表征。本实验集无机化学、有机化学、基础分析化学和仪器分析于一体,具有很强的实用性和可操作性,可作为有机化学实验中的综合性、设计性实验开设。  相似文献   
4.
Lameness is one of the most prevalent diseases affecting the welfare of cows in modern dairy production. Lameness leads to behavioral changes in severely lame cows, which have been investigated in much detail. For early detection of lameness, knowledge of the effects of moderate lameness on cow behavior is crucial. Therefore, the behavior of nonlame and moderately lame cows was compared on 17 Swiss dairy farms. On each farm, 5 to 11 nonlame (locomotion score 1 of 5) and 2 to 7 moderately lame (locomotion score 3 of 5) cows were selected for data collection in two 48-h periods (A, B) separated by an interval of 6 to 10 wk. Based on visual locomotion scoring, 142 nonlame and 66 moderately lame cows were examined in period A and 128 nonlame and 53 moderately lame cows in period B. Between these 2 periods, the cows underwent corrective hoof trimming. Lying behavior, locomotor activity, and neck activity were recorded by accelerometers (MSR145 data logger, MSR Electronics GmbH, Seuzach, Switzerland), and feeding and rumination behaviors by noseband sensors (RumiWatch halter, ITIN + HOCH GmbH, Liestal, Switzerland). Furthermore, visits to the brush and the concentrate feeder, and the milking order position were recorded. In comparison with nonlame cows, moderately lame cows had a longer lying duration, a longer average lying bout duration, and a greater lateral asymmetry in lying duration. Average locomotor activity, locomotor activity during 1 h after feed delivery or push-ups, and average neck activity were lower in moderately lame cows. Eating time and the number of eating chews (jaw movements) were reduced in moderately lame compared with nonlame cows, whereas no effect of moderate lameness was evident for ruminating time, number of ruminating chews and boluses, and average number of ruminating chews per bolus. Moderately lame cows visited the concentrate feeder and the brush less frequently, and they were further back in the milking order compared with nonlame cows. In conclusion, nonlame and moderately lame cows differed in a biologically relevant way in many of the behavioral variables investigated in this study. Therefore, the use of these behavioral changes seems to be promising to develop a tool for early lameness detection.  相似文献   
5.
We study magnetic-field directed self-assembly of magnetic nanoparticles onto templates recorded on perpendicular magnetic recording media, and quantify feature width and height as a function of assembly time. Feature widths are determined from Scanning Electron Microscope (SEM) images, while heights are obtained with Atomic Force Microscopy (AFM). For short assembly times, widths were ~150 nm, while heights were ~14 nm, a single nanoparticle on average with a 10:1 aspect ratio. For long assembly times, widths approach 550 nm, while the average height grows to 3 nanoparticles, ~35 nm; a 16:1 aspect ratio. We perform magnetometry on these self-assembled structures and observe the slope of the magnetic moment vs. field curve increases with time. This increase suggests magnetic nanoparticle interactions evolve from nanoparticle–nanoparticle interactions to cluster–cluster interactions as opposed to feature–feature interactions. We suggest the aspect ratio increase occurs because the magnetic field gradients are strongest near the transitions between recorded regions in perpendicular media. If these gradients can be optimized for assembly, strong potential exists for using perpendicular recording templates to assemble complex heterogeneous materials.  相似文献   
6.
The consumption of healthful foods is relevant for the well-being of society. However, understanding healthfulness may be difficult because, in some cultures (i.e., the U.S.), individuals assume that unhealthy equals tasty, an association that does not hold in other contexts (i.e., France). Auditory cues could serve to inform consumers about the expected experience with food and thus could signal the sensory experience of a healthy product. This research contributes to the literature on the use of sound symbolism for analysis of the influence of onomatopoeias as packaging information that influences the expected healthfulness of a bottled drink. The study is a 4 × 4 mixed-model experiment. Grouping was done according to onomatopoeia variables as follows: “Fizz,” “Glup,” “Ahhh,” and control. Beverage color, a within-subject variable, was grouped as green, yellow, red, and control. Results show that the healthful concept is defined in two dimensions: fulfilling and light. Onomatopoeias motivated the experience of a less fulfilling beverage, which had the strongest effect on “Fizz” condition. For the light dimension, “Ahhh” diminishes the perception of light, thus creating the idea that the drink is high in calories. This study reaches out to food industries on the need to find the most consistent and pleasurable sound associated with their products. This will enable food industries to provide information to consumers as well as ascertain how much they enjoy the product.  相似文献   
7.
8.
The estimation of the release conditions is critical input to subsequent risk assessment accident analysis. To this respect a new homogeneous non-equilibrium two-phase model is proposed to simulate the depressurization from stagnation conditions leading to the bubbly flow regime. The proposed model, being intermediate between HEM (homogeneous equilibrium) and HFM (homogeneous frozen) models, presents no discontinuity in the liquid phase depressurization path gradient and therefore no discontinuity in sound speed. The proposed model is successfully validated against the NASA hydrogen critical flow experiments and compared against predictions from both HEM and HFM, using hydrogen physical properties from NIST. An increase of the pressure difference between stagnation and the intersection of isentropic with saturation line leads to increase of the choked mass flux, decrease of the throat to stagnation pressure ratio, decrease of the liquid superheat and decrease of the vapor quality. The proposed model was found to overestimate the experimental throat mass fluxes by no more than 10% and underestimate the experimental throat to stagnation pressure ratios by no more than 50%, while predicted liquid superheat values range from 3.8 to 11% of the saturation temperature. Deviations between models were found to increase for low values of the pressure difference parameter, where non-equilibrium effects become more important. Under these conditions the throat mass flux is underestimated by maximum 20% by HEM and overestimated up to 32% by HFM, while the throat to stagnation pressure ratio is overestimated by up to 72% and underestimated by 80% respectively.  相似文献   
9.
Drying of agricultural produce like paddy grains is necessary for reducing moisture content in them to the required level towards diminishing the deterioration and enhancing the storage time. Conventionally, open-space sun drying is widely used to reduce the moisture content of the most of the agricultural produce.. Now-a-day, so many solar dryers are used for drying agricultural produce. In the present work, a double-pass oscillating bed with a double-pass flat plate collector has been used for drying of non-parboiled paddy grains. The bed oscillated at a frequency of 2.75 Hz. The oscillating bed solar dryer can dry 45 kg of non-parboiled paddy grains in just a single day to the required level of moisture content, and the average moisture present in the dried grains was 13.55%. The average dryer thermal efficiency and pick-up efficiency in non-parboiled paddy were 28.79% and 52.17%, respectively.  相似文献   
10.
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