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In order to improve the road performance of asphalt mixture in high altitude regions, different amounts of UV absorber(UV-531)/naphthenic oil(NPO) were selected for the composite modification of SBS asphalt. To investigate the effect of compound modifiers on the road performance of SBS modified as-phalt and mixtures. The results showed that the UV-531/NPO compound modifier significantly improved the low-temperature deformability and temperature-sensitive properties of SBS asphalt of SBS asphalt com-pared to the original SBS asphalt, but reduced the high-temperature performance of the asphalt(ductility increased by 117.6%, equivalent brittle point and temperature sensing coefficient decreased by 52.0% and 11.9%, equivalent softening point reduced by 2.3 °C). At the same time, the compound modifier can significantly improve the low-temperature crack resistance of the mixture (9.61% reduction in bending stiffness modulus and 11.20% increase in maximum bending and tensile strain). However, it will have a certain degree of negative impact on its high-temperature stability and water stability. High altitude regions mainly consider the low-temperature crack resistance of the mixture. Hence, UV-531/NPO Compound modified asphalt and its mixture have great potential for application. [ABSTRACT FROM AUTHOR]

Mapping crop distribution using satellite technology is an effective approach for gaining information about food production over broad, regional scales. However, crop classification in high altitude regions from satellite platforms remains challenging, due to the spatial heterogeneity caused by the complex planting patterns. Moreover, the frequent cloud cover makes it difficult to collect time-series imagery for these regions. Thus, this study used a mosaic of single images of Gaofen-6 data to map the crop distribution in high altitude regions of Xining City and Haidong City prefectures of Qinghai Province, China. To improve the accuracy of the crop classification, random forest-recursive feature elimination (RF-RFE) was used to determine an optimal feature subset from existing spectral, texture and topographic features. Then, a two-layer stacking generalization ensemble model, incorporating Random Forest, XGBoost and AdaBoost, was trained. The results reveal that the stacking algorithm outperformed the other single classifiers, with overall accuracy higher than 85% (87.89% for the optimal feature subset and 85.38% for the original spectral band subset). In addition, the user’s and producer’s accuracies for wheat, rape and maize field all exceeded 90%. Elevation was the variable with the highest importance score, illustrating its importance in crop classification of high altitude regions. Overall, the framework, combining RF-RFE and a stacking algorithm, can improve the accuracy of the crop classification in high altitude regions.

The crack problem in mass concrete is a difficult problem to thoroughly solve, especially for the crack of dam construction in high-altitude regions. High altitude regions have the fundamental features of a dry climate and strong solar radiation. When dam construction is performed under these special climate conditions, temperature control and crack prevention become more difficult problems. Based on the high altitude region's dam construction conditions, the existing temperature control measures were optimized by combining the three-dimensional finite element method. The synchronous cooling zone's temperature control technique is adopted to lower the temperature gradient in the dam's height direction, coordinate the deformation of the upper and lower layers, and reduce mutual constraints between the upper and lower layers to further reduce the temperature stress. Calculation results show that the adoption of synchronous cooling zones and the set of longitudinal joints can effectively reduce mutual constraints, increase the safety factor, and prevent cracks. This method can be considered an important reference to dam projects in high-altitude regions. [ABSTRACT FROM AUTHOR]

The crack problem in mass concrete is a difficult problem to thoroughly solve, especially for the crack of dam construction in high-altitude regions. High altitude regions have the fundamental features of a dry climate and strong solar radiation. When dam construction is performed under these special climate conditions, temperature control and crack prevention become more difficult problems. Based on the high altitude region’s dam construction conditions, the existing temperature control measures were optimized by combining the three-dimensional finite element method. The synchronous cooling zone’s temperature control technique is adopted to lower the temperature gradient in the dam’s height direction, coordinate the deformation of the upper and lower layers, and reduce mutual constraints between the upper and lower layers to further reduce the temperature stress. Calculation results show that the adoption of synchronous cooling zones and the set of longitudinal joints can effectively reduce mutual constraints, increase the safety factor, and prevent cracks. This method can be considered an important reference to dam projects in high-altitude regions.

Large-and-Sparse-particle Clouds (LSC), characterized by large particle size (radius > 50 μm) and small number concentration (<104 m−3), were observed with the space-borne lidar, Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), and with the space-borne 94-GHz cloud profiling radar (CPR). CALIOP was found to be less sensitive to the LSC as compared to CPR because of the particle size distribution of LSC; hence, the cloud type is different from usual ones because CALIOP is generally more sensitive to clouds as compared to CPR when there is no lidar attenuation. An empirical criterion was introduced to identify the LSC from CALIOP and CPR data. The data analysis showed that the LSC tend to appear at high latitudes. The lifetime of LSC would be in the order of hours, because the terminal velocity of LSC particles exceeded 1 km h−1. LSC would not be fallstreak because no cloud existed above. LSC appeared to destroy supercooled clouds (SC) because their cloud top heights were higher as compared to SC, and because LSC and SC did not tend to coexist. Because of their thin optical depth, LSC did not directly impact radiative forcing; however, LSC may indirectly influence radiative forcing through changes in the distribution of SC. [ABSTRACT FROM AUTHOR]

Highlights • Using Nano-TiO 2 in asphalt improves the rheological property and aging resistance. • MHEA mixture has superior resistance to rutting and low-temperature cracking. • MHEA mixture performs excellently in recurrent freeze-thaw cycle resistance. Abstract To resist the strong solar ultraviolet (UV) radiation and large temperature/moisture fluctuation in high altitude regions, a high-elasticity asphalt (HEA) mixture containing inorganic Nano-titanium dioxide (Nano-TiO 2) is proposed. This paper presents a laboratory study on the performance of Nano-TiO 2 modified HEA asphalt (MHEA) and MHEA mixtures. Rheological properties and UV-aging resistance of asphalt binder were first assessed using dynamic shear rheometer, bending beam rheometer and UV weathering oven. Furthermore, mixture properties, including rutting resistance, low-temperature cracking resistance, moisture stability, UV-aging resistance and recurrent freeze-thaw cycle resistance, were evaluated in the laboratory. Results show that addition of Nano-TiO 2 can improve the high-temperature rheology and UV-aging resistance of HEA asphalt, with no obvious influence on low-temperature rheology. In addition, When MHEA asphalt is used, the rutting resistance and low-temperature cracking resistance can be improved approximately to twice that of styrene–butadiene–styrene (SBS) mixture. In term of recurrent freeze-thaw cycle resistance, MHEA mixture performs better than SBS mixture, as reflected in smaller void structure damage, higher tensile strength ratio and lower freeze-thaw damage ratio at the same freeze-thaw cycles. The findings indicate that MHEA mixture has a great potential to be applied in asphalt pavement in high altitude regions. [ABSTRACT FROM AUTHOR]

The grapevine production in high altitude regions of southern Brazil is recent and there is little information about the phenological stages and thermal requirements of different grape varieties. The objective of this study was to determine the phenology and thermal requirements of Chardonnay, Sauvignon Blanc, Cabernet Sauvignon, Merlot, Pinot Noir, Cabernet Franc and Sangiovese. The experiment was conducted at the Experimental Station of São Joaquim, EPAGRI, (28"1T39" S; 49°55'56" W, altitude 1,415 meters). The phenological stages evaluated were bud break, flowering, change in berry skin color and maturity, during seasons 2004/05, 2005/06 and 2006/07. Thermal requirements were calculated by degree-days, considering base temperature of 10°C. At harvest, technological maturity was determined by analyses of total soluble solids, titratable acidity and pH. It was observed a delay in vine cycle, because harvest occured later in this place than in other Brazilian regions. The thermal durations are a good indicator of vine development phases. Regions above 1,300m should give preference to varieties with cycle between September 15 and April 15. [ABSTRACT FROM AUTHOR]

A produção de uvas viníferas nas regiões de elevada altitude do estado de Santa Catarina é recente e há poucas informações disponíveis a respeito das características fenológicas e das exigências térmicas para as variedades utilizadas. O objetivo deste trabalho foi caracterizar o comportamento fenológico e determinar as exigências térmicas das variedades Chardonnay, Sauvignon Blanc, Cabernet Sauvignon, Merlot, Pinot Noir, Cabernet Franc e Sangiovese. A área experimental foi instalada na Estação Experimental da EPAGRI, localizada em São Joaquim (28°17'39"S; 49°55'56"W, altitude 1.415m). Os estádios fenológicos avaliados foram início da brotação, floração, mudança de cor das bagas e maturidade nos ciclos produtivos de 2004/05, 2005/06 e 2006/07. A exigência térmica das variedades foi calculada empregando-se o somatório de graus-dia, considerando-se temperatura-base para a videira de 10°C. Na colheita, a maturação tecnológica foi determinada através das análises de sólidos solúveis totais, acidez titulável e pH. O ciclo das variedades viníferas avaliadas na região de São de Joaquim é mais longo do que o observado em outras regiões produtoras do Brasil. A duração térmica é um bom indicador de desenvolvimento das fases do ciclo da videira. Para as regiões com altitude acima de 1.300m, deve-se dar preferência para o plantio de variedades com ciclos entre 15 de setembro até 15 de abril.The grapevine production in high altitude regions of southern Brazil is recent and there is little information about the phenological stages and thermal requirements of different grape varieties. The objective of this study was to determine the phenology and thermal requirements of Chardonnay, Sauvignon Blanc, Cabernet Sauvignon, Merlot, Pinot Noir, Cabernet Franc and Sangiovese. The experiment was conducted at the Experimental Station of São Joaquim, EPAGRI, (28°17'39" S; 49°55'56" W, altitude 1,415 meters). The phenological stages evaluated were bud break, flowering, change in berry skin color and maturity, during seasons 2004/05, 2005/06 and 2006/07. Thermal requirements were calculated by degree-days, considering base temperature of 10°C. At harvest, technological maturity was determined by analyses of total soluble solids, titratable acidity and pH. It was observed a delay in vine cycle, because harvest occured later in this place than in other Brazilian regions. The thermal durations are a good indicator of vine development phases. Regions above 1,300m should give preference to varieties with cycle between September 15 and April 15.

The Pangi-Chamba Himalaya (PCH) region is very pristine, unique, and virgin niche for bioresource exploration. In the current study, for the first time, the bacterial diversity of this region was investigated for potential cellulose degraders. A total of 454 pure bacterial isolates were obtained from diverse sites in the PCH region, and 111 isolates were further selected for 16S rDNA characterization based on ARDRA grouping. The identified bacteria belonged to 28 genera representing four phyla: Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes. Pseudomonas was most abundant genus, followed by Bacillus, Geobacillus, Arthrobacter, Paenibacillus, and Flavobacterium. In addition, six putative novel bacteria (based on 16S rDNA sequence similarity) and thermophiles from non-thermogenic sites were also reported for the first time. Screening for cellulose degradation ability on carboxymethyl cellulose plates revealed that 70.92% of bacteria were cellulolytic. The current study reports diverse bacterial genera (Arthrobacter, Paenibacillus, Chryseobacterium, Pedobacter, Streptomyces, Agromyces, Flavobacterium, and Pseudomonas) with high capacity for cellulose hydrolysis and cellulolytic functionality at wide pH and temperature not previously reported in the literature. Diverse bacterial genera with high cellulolytic activity in broad pH and temperature range provide opportunity to develop a bioprocess for efficient pretreatment of lignocellulosic biomass, which is currently being investigated.