Surface temperature

表面温度
  • 文章类型: Journal Article
    Landsat8和Landsat9卫星平台上的运营陆地成像仪(OLI)和热红外传感器(TIRS)仪器的数据受到云层的污染,卷云的贡献是最难检测和掩盖的。为了帮助解决这个问题,在OLI上实现了以1.375μm水蒸气吸收区域为中心的卷云检测通道(Band9),空间分辨率为30米。该波段尚未在美国地质调查局(USGS)公开发布的Collection2Landsat8/9Level2表面温度数据产品中充分利用。使用单通道算法生成温度产物。在地表温度检索过程中,冰云吸收来自温暖地球表面的红外辐射的影响,通常位于对流层的上部,并在低得多的温度(约220K)下重新发射,没有考虑。通过对样品1级TOA和2级表面数据产品的分析,我们发现,1级1.375μm波段图像中存在的薄卷云特征直接传播到2级表面数据产品。薄卷云污染导致的表面温度误差可能为10K或更大。以前,我们报道了一种经验和有效的技术,用于消除OLI图像中的薄卷云散射效应,利用1.375μm波段图像与位于0.4-2.5μm太阳光谱区域中的任何其他OLI波段图像之间的相关性。在这篇文章中,我们描述了这种技术的一种变体,可以应用于热带,利用1级1.375-μm波段图像和11-μmBT图像之间的相关性来有效去除薄卷云吸收效应。我们从在空间均匀的水面和不均匀的陆地/水边界区域上获取的三个数据集中得出的结果表明,如果将卷云去除的TOA11-μm波段BT图像用于检索2级表面温度(ST)数据产品,对于空间扩散的卷云场景,由产品中的薄卷云污染引起的误差可以减少到约1K。
    Data from the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS) instruments onboard the Landsat 8 and Landsat 9 satellite platforms are subject to contamination by cloud cover, with cirrus contributions being the most difficult to detect and mask. To help address this issue, a cirrus detection channel (Band 9) centered within the 1.375-μm water vapor absorption region was implemented on OLI, with a spatial resolution of 30 m. However, this band has not yet been fully utilized in the Collection 2 Landsat 8/9 Level 2 surface temperature data products that are publicly released by U.S. Geological Survey (USGS). The temperature products are generated with a single-channel algorithm. During the surface temperature retrievals, the effects of absorption of infrared radiation originating from the warmer earth\'s surfaces by ice clouds, typically located in the upper portion of the troposphere and re-emitting at much lower temperatures (approximately 220 K), are not taken into consideration. Through an analysis of sample Level 1 TOA and Level 2 surface data products, we have found that thin cirrus cloud features present in the Level 1 1.375-μm band images are directly propagated down to the Level 2 surface data products. The surface temperature errors resulting from thin cirrus contamination can be 10 K or larger. Previously, we reported an empirical and effective technique for removing thin cirrus scattering effects in OLI images, making use of the correlations between the 1.375-μm band image and images of any other OLI bands located in the 0.4-2.5 μm solar spectral region. In this article, we describe a variation of this technique that can be applied to the thermal bands, using the correlations between the Level 1 1.375-μm band image and the 11-μm BT image for the effective removal of thin cirrus absorption effects. Our results from three data sets acquired over spatially uniform water surfaces and over non-uniform land/water boundary areas suggest that if the cirrus-removed TOA 11-μm band BT images are used for the retrieval of the Level 2 surface temperature (ST) data products, the errors resulting from thin cirrus contaminations in the products can be reduced to about 1 K for spatially diffused cirrus scenes.
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  • 文章类型: Journal Article
    目的:评估核心温度和表面温度(ΔT)之间的差异作为心力衰竭(HF)预后的指标。患者和方法:对253例HF患者的核心温度和表面温度进行了测量。分析ΔT与HF预后指标的相关性。结果:ΔT≥2°C的患者更可能具有较低的左心室射血分数和较低的估计肾小球滤过率,更高水平的肌钙蛋白T,脑钠肽和降钙素原,和高尿素氮/肌酐比。ΔT升高1°C时,死亡风险增加32%,ΔT≥2°C组比ΔT<2°C组高4.36倍。结论:ΔT可用于预测HF患者的预后。
    [方框:见正文]。
    Aim: To evaluate the difference between core temperature and surface temperature (ΔT) as an index for the prognosis of heart failure (HF). Patients & methods: Core temperature and surface temperature were measured in 253 patients with HF. The association of ΔT with prognostic indicators of HF was analyzed. Results: Patients with ΔT ≥2°C were more likely to have lower left ventricular ejection fraction and lower estimated glomerular filtration rate, higher levels of troponin T, brain natriuretic peptide and procalcitonin, and high blood urea nitrogen/creatinine ratio. The risk of death increased by 32% for a 1°C increase in ΔT and was 4.36-times higher in the ΔT ≥2°C group than in the ΔT <2°C group. Conclusion: ΔT may be used to predict the prognosis of patients with HF.
    [Box: see text].
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  • 文章类型: Journal Article
    这项研究旨在探索红外热成像(IRT)作为水牛早期妊娠诊断的替代方法的潜力。不同区域的表面温度(ST)(眼睛,枪口,侧翼,和外阴)从人工授精当天(AI;第0天)开始使用IRT在27只水牛中测定,每第四天重复测量,直到AI后第24天。来自所有地区,在三个温度值下记录每个温度图中的ST(最大值,平均,minimum).在第30天通过超声检查确认妊娠状态,并将动物回顾性分组为妊娠或非妊娠,以分析热成像数据。在怀孕的水牛中,左侧的ST的所有三个值都明显更大(p≤0.05),while,左眼和外阴,只有最大值和平均值显著更大.相比之下,与未怀孕的水牛相比,怀孕的水牛的枪口最大ST显着较低(p≤0.05)。然而,右眼和右侧的ST在任何值下都没有显示出明显的温度变化。这些发现表明,IRT有可能在早期阶段识别与水牛怀孕相关的热变化。
    This study was designed to explore the potential of infrared thermography (IRT) as an alternate approach for early pregnancy diagnosis in buffaloes. The surface temperature (ST) of different regions (eyes, muzzle, flanks, and vulva) was determined in 27 buffaloes using IRT from the day of artificial insemination (AI; Day 0), and measurement was repeated every fourth day until Day 24 post-AI. From all regions, the ST in each thermograph was recorded at three temperature values (maximum, average, minimum). Pregnancy status was confirmed through ultrasonography on Day 30, and animals were retrospectively grouped as pregnant or non-pregnant for analysis of thermographic data. In pregnant buffaloes, all three values of ST were significantly greater (p ≤ 0.05) for the left flank, while, in the left eye and vulva, only the maximum and average values were significantly greater. By contrast, the maximum ST of the muzzle was significantly lower (p ≤ 0.05) in pregnant buffaloes compared to non-pregnant buffaloes. However, the ST of the right eye and right flank did not show significant temperature variation at any value. These findings suggest that IRT has the potential to identify thermal changes associated with pregnancy in buffaloes at an early stage.
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  • 文章类型: Journal Article
    通过营养不良对胎儿进行规划会影响后代的行为,新陈代谢,和对绵羊压力的敏感性。目的是确定母亲在妊娠期间营养受到限制的母羊的应激反应,然后暴露于新物体。使用了26岁的Corriedale母羊,这些母羊从受孕前23天至妊娠122天开始放牧高或低牧场津贴(HPA和LPA组)。母羊被单独隔离在一个新的地方10分钟,开始后5分钟,一个橙色的球被扔进了测试笔。在测试过程中记录母羊的行为。血蛋白,葡萄糖和皮质醇浓度,确定了心脏和呼吸频率以及直肠和表面温度。HPA母羊看球的次数往往大于LPA(6.7±1.0vs4.7±0.8,P=0.08)。LPA母羊的血清白蛋白浓度高于HPA母羊(3.2±0.1g/dLvs3.0±0.1g/dL,P=0.02),不管施加的压力。总的来说,在母羊宫内发育过程中应用的营养治疗并没有改变暴露于新物体后对社会隔离的应激反应。
    Fetal programming by subnutrition affects offspring\'s behaviour, metabolism, and sensitivity to stressors in sheep. The objective was to determine the stress response of ewes born to mothers nutritionally restricted during gestation to social isolation followed by exposure to a novel object. Twenty-six-year-old Corriedale ewes born to mothers who grazed high or low pasture allowances (HPA and LPA groups) from 23 days before conception until 122 days of gestation were used. Ewes were individually isolated in a novel place for 10 min, and 5 min after its beginning, an orange ball was dropped into the test pen. The ewes\' behaviours were recorded during the test. Blood proteins, glucose and cortisol concentrations, heart and respiratory rates and rectal and surface temperatures were determined. The number of times looking at the ball tended to be greater in HPA ewes than LPA (6.7 ± 1.0 vs 4.7 ± 0.8, P = 0.08). The LPA ewes had greater serum albumin concentration than HPA ewes (3.2 ± 0.1 g/dL vs 3.0 ± 0.1 g/dL, P = 0.02), regardless of the applied stressors. Overall, the nutritional treatments applied to ewes during their intrauterine development did not modify the stress responses to social isolation followed by exposure to a novel object.
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  • 文章类型: Journal Article
    当暴露于应激源时,动物中存在的大多数反应是由自主神经系统介导的。交感神经系统,被称为负责“战斗或逃跑”反应的人,引发心血管变化,如心动过速或血管舒缩改变,以恢复稳态。应激动物中体温的升高还激活外周代偿机制,例如皮肤血管舒张以增加热交换。由于皮肤血流量的变化会影响散热量,红外热成像被建议作为可以检测所述变化的工具。本综述旨在分析红外热成像作为评估应激相关自主活动的方法的应用。以及它们与家畜心血管和心率变异性的关系。
    Most of the responses present in animals when exposed to stressors are mediated by the autonomic nervous system. The sympathetic nervous system, known as the one responsible for the \"fight or flight\" reaction, triggers cardiovascular changes such as tachycardia or vasomotor alterations to restore homeostasis. Increase in body temperature in stressed animals also activates peripheral compensatory mechanisms such as cutaneous vasodilation to increase heat exchange. Since changes in skin blood flow influence the amount of heat dissipation, infrared thermography is suggested as a tool that can detect said changes. The present review aims to analyze the application of infrared thermography as a method to assess stress-related autonomic activity, and their association with the cardiovascular and heart rate variability in domestic animals.
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  • 文章类型: Journal Article
    牧场系统中的奶牛更容易受到热应激的影响。荷斯坦奶牛有黑色或红色的表型,后者对太阳辐射的吸收率较低。因此,这项研究的目的是评估在亚热带气候下,红色(R)皮毛的母牛是否比黑色(B)母牛更能抵抗炎热的天气。在寒冷和炎热的季节评估了R和B泌乳荷斯坦奶牛的内部和表面温度以及出汗率。在寒冷的季节,体温(n=9/组)在组间没有差异,但是R母牛的平均表面温度(n=13/组)较低(B:30.9±0.3°C;RW:29.6±0.3°C;p=0.02)。在炎热的季节,在轻度至中度热应激下,R母牛的平均体温(n=9/组)较低(B:38.75±0.01°C;R:38.62±0.1°C;p=<0.0001),而在表面温度上没有观察到差异(n=17/组)。最大内部温度和出汗率(n=11/组),在炎热的季节测量,在两个季节的高热评估数量没有差异。因此,在轻度至中度热应激条件下,表型之间的体温调节存在差异。然而,考虑到只观察到离散的差异,在轻度到中度的热应激下,红色和白色的外套不太可能有利于荷斯坦奶牛的福利。
    Dairy cows in pasture-based systems are more susceptible to heat stress. Holstein cows have the black or red phenotypes, the latter having lower absorbance of solar radiation. Therefore, the study\'s objective was to evaluate whether cows with red (R) coats are more resistant than black (B) cows to hot weather in a subtropical climate. R and B lactating Holstein cows were evaluated during the cold and hot seasons for internal and surface temperature and sweating rate. In the cold season, body temperature (n = 9/group) did not differ between groups, but the average superficial temperature (n = 13/group) was lower in R cows (B: 30.9 ± 0.3 °C; RW: 29.6 ± 0.3 °C; p = 0.02). In the hot season, under mild to moderate heat stress, mean body temperature (n = 9/group) of R cows was lower (B: 38.75 ± 0.01 °C; R: 38.62 ± 0.1 °C; p=<0.0001), whereas no difference was observed in superficial temperature (n = 17/group). The maximum internal temperature and sweating rate (n = 11/group), measured in the hot season, and the number of evaluations in hyperthermia in both seasons did not differ. Therefore, there were differences in thermoregulation between phenotypes under mild to moderate heat stress conditions. However, considering that only discrete differences were observed, the red and white coat is unlikely to benefit the Holstein cow\'s welfare under mild to moderate thermal stress.
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  • 文章类型: Journal Article
    科学创新正在颠覆传统的森林范式,水,和能量循环相互作用。这对我们理解树的主要因果途径有影响,森林,和植被覆盖(TFVC)影响局部和全球变暖/降温。许多人认为地表反照率和碳封存是TFVC影响全球变暖/变冷的主要因果途径。向外纬度移动,特别是,在积雪更重要的地方,表面反照率效应被认为超过了碳固存。通过提高地表反照率,因此,预计森林砍伐会导致地表冷却,而增加森林覆盖率被认为会导致变暖。观测数据,然而,一般支持相反的结论,表明地表反照率知之甚少。大多数人接受表面温度受表面反照率相互作用的影响,输入短波(SW)辐射,以及其余的分区,后反照率,SW辐射转化为潜热和显热。然而,在多大程度上避免显热形成首先是由水和TFVC的存在(不存在)介导的,目前尚不清楚。TFVC既介导陆地表面水的可用性,又驱动潜热产生的潜力(蒸散,ET)。虽然潜热与局部比全球降温/变暖更直接相关,它由光合作用和碳封存驱动,并为额外的云形成和云顶反射率提供动力,两者都推动了全球降温。TFVC损失减少了水的储存,沉淀回收,和顺风降雨潜力,从而推动ET(潜热)和云形成的减少。通过减少潜热,云的形成,和降水,因此,森林砍伐为变暖(显热形成)提供动力,这进一步减少了TFVC的生长(碳封存)。大规模的树木和森林恢复可以,因此,通过固碳和云形成的主要因果途径,对全球和地表温度冷却做出了重要贡献。
    Scientific innovation is overturning conventional paradigms of forest, water, and energy cycle interactions. This has implications for our understanding of the principal causal pathways by which tree, forest, and vegetation cover (TFVC) influence local and global warming/cooling. Many identify surface albedo and carbon sequestration as the principal causal pathways by which TFVC affects global warming/cooling. Moving toward the outer latitudes, in particular, where snow cover is more important, surface albedo effects are perceived to overpower carbon sequestration. By raising surface albedo, deforestation is thus predicted to lead to surface cooling, while increasing forest cover is assumed to result in warming. Observational data, however, generally support the opposite conclusion, suggesting surface albedo is poorly understood. Most accept that surface temperatures are influenced by the interplay of surface albedo, incoming shortwave (SW) radiation, and the partitioning of the remaining, post-albedo, SW radiation into latent and sensible heat. However, the extent to which the avoidance of sensible heat formation is first and foremost mediated by the presence (absence) of water and TFVC is not well understood. TFVC both mediates the availability of water on the land surface and drives the potential for latent heat production (evapotranspiration, ET). While latent heat is more directly linked to local than global cooling/warming, it is driven by photosynthesis and carbon sequestration and powers additional cloud formation and top-of-cloud reflectivity, both of which drive global cooling. TFVC loss reduces water storage, precipitation recycling, and downwind rainfall potential, thus driving the reduction of both ET (latent heat) and cloud formation. By reducing latent heat, cloud formation, and precipitation, deforestation thus powers warming (sensible heat formation), which further diminishes TFVC growth (carbon sequestration). Large-scale tree and forest restoration could, therefore, contribute significantly to both global and surface temperature cooling through the principal causal pathways of carbon sequestration and cloud formation.
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  • 文章类型: Journal Article
    在哺乳动物中,孕酮和雌激素影响应激反应。该研究旨在比较母羊在发情期或黄体期对社会隔离的生理和行为反应。将发情母羊和发情母羊(分别为n=10和8)在新地方分别分离10分钟。在测试期间记录母羊行为。皮质醇,血液蛋白和葡萄糖浓度,并在试验前后测定皮肤表面温度。皮质醇在试验结束后立即增加(P=0.02)。血清总蛋白(P=0.02),球蛋白(P<0.0001),发情期的血浆葡萄糖浓度(P=0.006)高于黄体期。发情期腹部皮肤表面温度高于黄体期(P=0.02)。发情期母羊站立不动的时间比黄体期母羊多(P=0.05)。总之,生理和行为反应根据发情周期的阶段而变化。这些结果凸显了未来研究的必要性,重点是生殖状态如何影响绵羊对不同管理方法的应激反应。
    In mammals, progesterone and estrogens affect the stress response. The study aimed to compare the physiological and behavioral responses to the social isolation of ewes during the estrus or luteal phase. Estrous and diestrous ewes (n = 10 and 8 respectively) were individually isolated in a novel place for 10 min. Ewes\' behavior was recorded during the test. Cortisol, blood proteins and glucose concentrations, and the skin surface temperature were determined before and after the test. Cortisol increased immediately after the test ended (P = 0.02). Serum total protein (P = 0.02), globulin (P < 0.0001), and plasma glucose (P = 0.006) concentrations were greater in estrus than in the luteal phase. The abdominal skin surface temperature was greater during estrus than during the luteal phase (P = 0.02). Ewes in estrus spent more time standing up immobile than ewes in the luteal phase (P = 0.05). In conclusion, the physiological and behavioral responses changed according to the phase of the estrous cycle. These results highlight the need for future studies focusing on how reproductive status influences the stress response to different management practices in sheep.
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  • 文章类型: Journal Article
    加工条件的适当选择直接有助于提高加工过程的性能。在加工过程中使用不同的方法对磨削表面进行冷却和润滑,但是每种方法都有自己的缺点。在这项研究中提出了一种新的冷却系统,以改善平面磨削中的表面粗糙度。使用水和防冻液的混合物作为冷却剂冷却工件,不直接接触刀具。工件表面的温度保持固定,并且执行工件的研磨。这种新颖的方法有几个好处,包括工件和工具表面不氧化,没有快速冷却引起的表面硬化,冷却剂中没有添加芯片,和扩展的磨削能力,无需更换。所提出的方法在四种钢合金上进行了测试,包括热加工和冷加工钢,以及两种改进的合金。测试涉及改变各种参数,例如切削深度,表面温度,和冷却剂流量,分析它们如何影响表面粗糙度。根据结果,所提出的方法对低铬钢合金非常有效。使用1.1191钢合金(一种改进的钢合金)的间接冷却系统获得最佳的表面粗糙度。总的来说,更好的结果(在较高的切削深度较低的粗糙度)在较高的冷却剂流速获得。
    Appropriate choice of machining conditions contributes directly to improved performance of the machining process. Cooling and lubricating the grinding surface in the machining process has been done using different methods, but each method has its own disadvantages. A new cooling system is proposed in this research to improve the surface roughness in flat-surface grinding. The workpiece is cooled using a mixture of water and antifreeze as a coolant, without directly contacting the cutting tool. The temperature of the workpiece surface remains fixed, and grinding of the workpiece is performed. This novel method has several benefits including no oxidation of workpiece and tool surfaces, no surface hardening from rapid cooling, no chip addition to the coolant, and extended grinding capabilities without replacement. The proposed methodology was tested on four steel alloys, including hot-worked and cold-worked steel, as well as two improved alloys. The tests involved changing various parameters such as the depth of cut, surface temperature, and coolant flow-rate, to analyze how they affected surface roughness. According to the results, the proposed method was remarkably efficient for low-chromium steel alloys. The best surface roughness was obtained using the indirect cooling system for the 1.1191 steel alloy (an improved steel alloy). In general, better results (lower roughness at higher cutting depth) were achieved at higher coolant flow-rates.
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  • 文章类型: Journal Article
    在这项研究中,广泛使用的MODISMxD11和MxD21地表温度(LST)和ERA5-陆地皮肤温度(SKT)和2m气温产品的趋势是使用2000-2021年土耳其266个站点的地面观测获得的2m气温趋势进行验证,已知地形复杂。结果表明,较冷的区域比温暖的区域具有更高的时间温度变异性。MxD21和MxD11产品比ERA5-Land产品高4.4°C和2.9°C,分别,而ERA5-Land产品(SKT和2m)的平均值几乎相似(12.5°C)。在地形和灌溉活动较为复杂的地区,MODIS和ERA5-Land数据之间的一致性明显较低,尽管产品在研究区域内表现出很高的线性关系。虽然2月份的趋势一直远高于其他月份(MODIS和ERA5-Land的2.2和1.4°C/十年,分别),总体MODIS皮肤温度产品(0.7°C/十年)通常表现出比ERA5-陆地皮肤和空气温度趋势(0.94°C/十年)更小的趋势。结果表明,MODIS和ERA5-Land趋势,与观察结果高度一致,在没有长期台站记录的情况下,可能会取代观测。
    In this study, the trend of widely used MODIS MxD11 and MxD21 Land Surface Temperature (LST) and ERA5-Land Skin Temperature (SKT) and 2 m air temperature products were validated using 2 m air temperature trends obtained by ground observations from 266 stations in 2000-2021 over Turkey, known to have complex topography. The results show that colder regions have substantially higher temporal temperature variability than warmer ones. MxD21 and MxD11 products are 4.4 °C and 2.9 °C warmer than ERA5-Land products, respectively, while ERA5-Land products (SKT and 2 m) have nearly similar averages (12.5 °C). The consistency between MODIS and ERA5-Land data is significantly lower over areas with more complex topography and irrigation activities, despite the fact that the products show a high linear relationship over the study area. While February trends are consistently much higher than other months (2.2 and 1.4 °C/decade for MODIS and ERA5-Land, respectively), overall MODIS skin temperature products (0.7 °C/decade) generally exhibit smaller trends than ERA5-Land skin and air temperature trends (0.94 °C/decade). The results suggested that MODIS and ERA5-Land trends, which are highly consistent with observations, might replace observations in the absence of long-term station-based records.
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