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2022 ◽  
Vol 269 ◽  
pp. 112840
Author(s):  
Haili Li ◽  
Chang-Qing Ke ◽  
Qinghui Zhu ◽  
Mengmeng Li ◽  
Xiaoyi Shen

Author(s):  
N. Bouhroum ◽  
B. Bensahli

Background: Among the dairy cattle production problems in Algeria, mastitis rank first in terms of socio-economic impact. Our aim is to identify the state of well-being of the udder in order to manage and control mastitis related problems. Methods: The pH analysis of 177 cow milk samples was performed at two farms located in the Sidi Mhamed Benali region in northwest Algeria associated with an assessment (of the udder’s cleanliness degree, the udder’s position, the teat’s hyperkeratosis lesion and the ITH) out over a period of one year (2020-2021). Result: Analysis of mean (of cleanliness, udder position and ITH) between cold and warm season were significantly different at a value of [(4.11; 2.75); (5.19; 4.11); (56.96; 73.76)] respectively. The paper test revealed that the health of the udder is influenced by any variation in cleanliness and the ITH whose correlation coefficient is equal to 0.72 leading to the appearance of subclinical mastitis during the cold season. While during the hot season the bad milking procedure is incriminated in the appearance of hyperkeratosis lesion at a mean value equal to 1 (smooth ring stage) inducing the appearance of clinical mastitis with p less than 0.05, moreover the cows in first lactation are the most influenced by these elicited factors. In conclusion, monitoring and evaluating the well-being of the udder around the parturition is a tool that allows better prevention of mastitis.


2022 ◽  
Vol 10 (1) ◽  
pp. 97
Author(s):  
Sergey V. Vostokov ◽  
Anastasia S. Vostokova ◽  
Svetlana V. Vazyulya

Based on satellite data from the SeaWiFS, MODIS-Aqua, and MODIS-Terra scanners, the long-term dynamics of coccolithophores in the Black Sea and their large-scale heterogeneity have been studied. During the twenty years in May and June, mass development of coccolithophores population of different intensities was recorded annually. Summer blooms of coccolithophores reached peak levels in 2006, 2012, and 2017, after abnormally cold winters. It was noted that in conditions of low summer temperatures, the blooming of coccolithophores could be significantly reduced or acquire a local character (2004). In the anomalous cold summer of 2001, coccolithophore blooms were replaced by the mass growth of diatoms. Over twenty years, numerous signs of coccolithophores mass development in the cold season have been revealed. Winter blooms develop mainly in warm winters with periods of low wind activity. The formation of a thermocline and the surface layer’s stability are essential factors for initiating winter blooms of coccolithophores. It was noted that after the winter blooms of coccolithophores, their summer growth was poorly expressed. It is shown that during periods of rapid growth, the bulk of coccolithophores is concentrated in the upper mixed layer and thermocline. During the blooming period, the share of coccolithophores in phytoplankton biomass constituted 70–85%. The intensity of coccolithophore’s blooms is associated with the previous diatoms’ growth level. The effect of eddies circulation on the distribution and growth of coccolithophores is considered.


Author(s):  
John T. Braggio ◽  
Eric S. Hall ◽  
Stephanie A. Weber ◽  
Amy K Huff

Optimal use of aerosol optical depth (AOD)-PM2.5 fused surfaces in epidemiologic studies requires homogeneous temporal and spatial fused surfaces. No analytic method is currently available to evaluate the spatial dimension. The temporal case-crossover design was modified to assess the association between Community Multiscale Air Quality (CMAQ) lag grids and four respiratory-cardiovascular hospital events. The maximum number of adjacent lag grids with the expo-sure-health outcome association determined the size of the homogeneous spatial area. The largest homogeneous spatial area included 5 grids (720 km2) and the smallest 2 grids (288 km2). PMC and PMCK analyses of ED asthma, IP asthma, IP MI, and IP HF were significantly higher in rural grids without air monitors than in urban with air monitors at lag grids 0, 1, and 01. Grids without air monitors had higher AOD-PM2.5 concentration levels, poverty percent, population density, and environmental hazards than grids with air monitors. ED asthma, IP MI, and HF PMCK ORs were significantly higher during the warm season than during the cold season at lag grids 0, 1, 01, and 04. The possibility of elevated fine PM and other demographic and environmental risk factors contributing to elevated respiratory-cardiovascular diseases in persons residing in rural areas was discussed.


Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 143
Author(s):  
Hyung-Kweon Kim ◽  
Si-Young Lee ◽  
Jin-Kyung Kwon ◽  
Yong-Hyeon Kim

This study compared and analyzed changes in the microclimate and thermal environment inside single-span greenhouses covered with a single layer of plastic film, polycarbonate (PC), and glass. The results of the experiment show that the PC-covered greenhouse was the most favorable for managing the nighttime heating effect during the cold season. However, the glass-covered greenhouse was found to be the most favorable for managing the cooling effect during the hot season. Although the plastic-covered greenhouse was inexpensive and easy to install, the air temperature inside varied significantly, and it was difficult to control its indoor environment. The thermal load leveling values showed that the PC-covered greenhouse had the lowest variation, confirming its superiority in terms of environmental control and energy savings. In terms of the overall heat transfer, heat was generally transferred from the interior to the exterior of the greenhouses. In the plastic-covered greenhouse, however, heat was transferred in the opposite direction at night due to the influence of radiant cooling. The occurrence of the minimum and maximum heat transfer values had a tendency similar to that of the occurrence of the minimum and maximum air temperatures inside the greenhouses.


2022 ◽  
Author(s):  
Ruping Mo ◽  
Hai Lin ◽  
Frédéric Vitart

Abstract Atmospheric rivers (ARs) are long and narrow bands of enhanced water vapour flux concentrated in the lower troposphere. Many studies have documented the important role of cold-season ARs in producing heavy precipitation and triggering extreme flooding in many parts of the world. However, relatively little research has been conducted on the warm-season ARs and their impacts on extreme heatwave development. Here we show an anomalous warm-season AR moving across the North Pacific and its interaction with the western North American heatwave in late June 2021. We call it an “oriental express’’ to highlight its capability to transport tropical moisture to the west coast of North America from sources in Southeast Asia. Its landfall over the Alaska Panhandle lasted for more than two days and resulted in significant spillover of moisture into western Canada. We provide evidence that the injected water vapour was trapped under the heat dome and may have formed a positive feedback mechanism to regulate the heatwave development in western North America.


Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 75
Author(s):  
Jin Ding ◽  
Guoping Zhang ◽  
Shudong Wang ◽  
Bing Xue ◽  
Jing Yang ◽  
...  

Based on the hourly visibility data, visibility and its changes during 2010–2020 at monthly and annual time scales over 47 international airports in China are investigated, and nine artificial-intelligence-based hourly visibility prediction models are trained (hourly data in 2018–2019) and tested (hourly data in 2020) at these airports. The analyses show that the visibility of airports in eastern and central China is at a poor level all year round, and LXA (in Lhasa) has good visibility all year round. Airports in south and the northwest China have better visibility from May to October and poorer visibility from November to April. In all months, the increasing visibility mainly occurs in the central, northeast and coastal areas of China, while decreasing visibility mainly appears in the western and northern parts of China. In spring, summer and autumn, the changes difference between east and west is particularly obvious. This East–West distribution of trends is obviously different from the North–South distribution shown by the mean. For all airports, good visibility mainly occurs from 14:00–18:00 p.m. Beijing Time, while poor visibility mainly concentrates from 22:00 p.m. to 12:00 p.m. the next day, especially between 3:00–9:00 a.m. Our proposed artificial intelligence algorithm models can be reasonably used in airport visibility prediction. In particular, most algorithm models have the best results in the visibility prediction over HFE (in Hefei) and SJW (in Shijiazhuang). On the contrary, the worst forecast results appear at LXA and LHW (in Lanzhou) airports. The prediction results of airport visibility in the cold season (October–December) are better than those in the warm season (May–September). Among the algorithm models, the prediction performance of the RF-based model is the best.


2022 ◽  
Vol 443 ◽  
pp. 106701
Author(s):  
Jouni Salmela ◽  
Saija Saarni ◽  
Linnea Blåfield ◽  
Markus Katainen ◽  
Elina Kasvi ◽  
...  

Author(s):  
Mykhaylo Bozhenko ◽  
Tatiana Izhevska

A promising trend in air conditioning systems is the use of indirect evaporative cooling, but in the classic version it is effective in dry and hot climates. For the need to maintain comfortable air parameters in public buildings, it is not possible to fully implement such a process in the conditions of Ukraine (the relative humidity of the outside air ranges from 63 to 75 %). The aim of the work is to increase the energy efficiency of air conditioning systems with standard equipment through partial evaporative cooling and use for cooling water in cooling towers of the air removed from the rooms during the warm season, and in the cold season - use of the exhaust air for preheating the supply air in heat exchanger. A corresponding system diagram was developed and computational studies of a direct-flow circuit and a circuit with recirculation were carried out for one of the educational buildings of the Igor Sikorsky Kyiv Polytechnic Institute. According to the results of calculating the direct-flow circuit in the warm period, the energy efficiency of indirect evaporative cooling was 23.5 %. The annual amount of recovered heat of ventilation emissions for this scheme in the cold period was 3731 GJ / year, and the economic effect - 1473185 UAH / year. For a circuit with recirculation during a warm period, the greatest effect of indirect evaporative cooling is achieved with a recirculation rate of 10 %, and for the overall decrease in the cooling capacity of the air conditioner during this period the greatest impact is not indirect evaporative cooling, but recirculation. In the cold season, the greatest utilization effect is also achieved with a 10 % recirculation rate.


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