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1.
Environ Monit Assess ; 193(7): 427, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34143311

RESUMEN

Arid environments face extreme risk from contemporary climate change; therefore, predicting the shifts in species distribution range and niche breadth in these environments assumes urgent research priority. Here we report the potential distribution and predict future distribution range of two model plant species typically representing contrasting environments across Asia and Africa: hot-arid Ephedra foliata and cold-arid E. gerardiana. We adopted a comparative modelling approach and used occurrence points from extensive field surveys, supplemented with herbaria records and publicly available distribution data. Our study reveals that currently an area of 8.797334 × 106 km2 (8.8%) is potentially suitable for E. foliata and nearly half 4.759326 × 106 km2 (4.8%) for E. gerardiana. Under future climate change scenarios, distribution range of E. foliata is predicted to expand but contract in E. gerardiana. Similarly, E. foliata showed broader niche breadth which is predicted to increase under B1 (0.097-0.125) and B2 (0.878-0.930) climatic change scenarios. In contrast, E. gerardiana had narrower niche breadth and expected to further decrease under B1 (0.081-0.078) and B2 (0.878-0.854). The most influential bioclimatic variable governing the potential distribution and niche breadth of E. foliata was the precipitation of warmest quarter, whereas that of E. gerardiana was temperature seasonality. The results from our study can help in developing potential indicator plant species for assessment and monitoring of distribution range shifts in response to changing climate in the arid environments.


Asunto(s)
Cambio Climático , Monitoreo del Ambiente , África , Asia , Ecosistema
2.
Sud Med Ekspert ; 63(6): 45-50, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-33180414

RESUMEN

Based on the analysis of literature data, demonstrated the relevance of further research to establish the prescription of death, including in a hot arid zone. Taking into account the climate of the seasons of Uzbekistan was stressed the importance of a comprehensive assessment of the dynamics of the development of cadaveric changes and supravital reactions, together with the results of biochemical, morphological and morphometric studies of the brain, other organs and tissues at different times of the postmortem period in certain groups. It could be used to develop additional criteria for establishing the onset of death in a hot arid zone.


Asunto(s)
Prescripciones , Humanos , Estaciones del Año , Uzbekistán
3.
Int J Biometeorol ; 62(10): 1901-1909, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30128911

RESUMEN

This cross-cultural research is an inaugural attempt to investigate the outdoor thermal comfort and the effect of cultural and social differences in hot arid climates. Case studies were carefully selected in two different parts of the world (Marrakech in North Africa and Phoenix, Arizona, in North America) to represent two different cultures in similar climatic context. Field surveys, carried out during winter and summer, included structured interviews with a standard questionnaire, observations and microclimatic monitoring. The results demonstrate a wide thermal comfort zone and prevalence of air-conditioning influencing thermal comfort requirements. The work also provides evidence of substantial cross-cultural differences in thermal comfort requirements between residents in Marrakech and Phoenix. It shows that adaptive measures, such as level of clothing, changing place, cold drinks consumption and thermal experience, varies between cultures and this influences the thermal evaluation of visitors in outdoor spaces in the hot arid climate. Evidence between the time spent in outdoor spaces and thermal expectations has been found. Moreover, environmental variables such as air temperature and solar radiation have a great impact on the use of the outdoor spaces in the hot arid climate and may determine the number of people in urban spaces. The study also identified significant differences in thermal comfort requirements between different socio-economic groups, highlighting the need for comfortable open spaces.


Asunto(s)
Comparación Transcultural , Sensación Térmica , África del Norte , Arizona , Calor , Humanos , Japón , América del Norte , Condiciones Sociales , Suecia
4.
J Therm Biol ; 59: 92-102, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27264894

RESUMEN

Climate can greatly affect building design, life style and thermal perception for all groups of people; however, this phenomenon has not yet been rigorously evaluated in China's hot-arid climate. The aim of this paper is to present the results of a thermal comfort survey by evaluating the influence of the hot-arid climate upon the behavioural patterns and thermal comfort responses of 160 residents in 65 traditional vernacular houses in Turfan, China, in 2011. In this survey, there were 206 sets of effective data, and the features of the traditional residential buildings and the human behaviour patterns in Turfan were described and analysed. The results showed that the diversified courtyards and shade spaces were the most obvious features of traditional houses in Turfan. People here typically spend most of their time in one of two spaces for eating, resting, and entertaining. It was found that the preferred temperature was 26.5°C. The preferred air velocity occurred at 0.62m/s. A suitable air velocity range of 0.15-1.24m/s was suggested in Turfan. Moreover, the neutral temperature of the local people was 30.1°C (tg or to). The upper limits of the 80% acceptable zone by using the direct and indirect acceptability method were 32.7 and 33.8°C, respectively. The neutral temperature and upper limit of the acceptable zone in Turfan were higher than those of the adaptive standards. Attention should be paid to the role of thermal comfort in influencing building design by using simple passive cooling strategies. The above results are believed to be potentially valuable for the design and evaluation of residential buildings located in hot-arid climate.


Asunto(s)
Aclimatación , Clima Desértico , Vivienda , Adulto , Arquitectura , Regulación de la Temperatura Corporal , China , Femenino , Calor , Humanos , Humedad , Masculino , Persona de Mediana Edad , Ropa de Protección , Sensación Térmica , Adulto Joven
5.
Life (Basel) ; 13(6)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37374022

RESUMEN

The high environmental temperature is one of the main factors challenging the broiler industry during the hot seasons due to it causing more thermal stress. This study aimed to find the effects of heat stress under hot arid environments on the growth performance, carcass traits, and nutritional composition of breast meat in broiler chickens. A total of 240 broiler chickens were allocated into two groups: (1) a control group (thermoneutral environment (TN); 24 ± 0.17 °C) and (2) a heat stress (HS) group, with 30 replicates in each environment. From d 25 to 35 of age, the broiler chickens in the HS group were exposed to 8 h/day of thermal stress (34 ± 0.71 °C) from 8:00 am to 4:00 pm, while the actual recorded value of ambient temperature was 31 °C on average with a relative air humidity (RH) between 48 and 49% for 10 consecutive days (d 25-35 of age). The live body weight (BW), weight gain, and feed intake significantly deteriorated (p < 0.05), and the feed conversion ratio tended to deteriorate (p = 0.055) in the HS group. The hot and cold carcass yields increased (p < 0.05), while the relative heart and liver weights decreased (p < 0.05) in the broiler chickens exposed to HS. The breast meat yield tended to decrease (p = 0.057), while wing meat yields increased significantly (p = 0.050) in heat-stressed broiler chickens. The shrinkage of the carcass percentage increased during chilling (p < 0.001) in the HS group. The ultimate pH values; cooking loss; and contents of moisture, crude protein, and fat of breast meat showed no response (p > 0.05) between the TN and HS groups. The heat-stressed broiler chickens presented lower levels of arachidonic acid (C20:4 (n-6)) (p = 0.01) and eicosadienoic acid (C20:2 (n-6)) (p = 0.050) in the breast meat, while the variations in n-3 polyunsaturated fatty acid were insignificant (p > 0.05) between the groups. In conclusion, our findings confirmed that the hot arid environments could reduce the production performance of broiler chickens and increase carcass shrinkage during chilling, but did not compromise the n-3 polyunsaturated fatty acid and cooking loss in the breast meat.

6.
Plants (Basel) ; 11(16)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36015423

RESUMEN

Tephrosia is widely distributed throughout tropical, subtropical, and arid regions. This genus is known for several biological activities, including its anti-Candida activity, which is mainly attributed to prenylated flavonoids. The biological activities of most Tephrosia species have been studied, except T. apollinea. This study was conducted to investigate the underlying anti-Candida activity of T. apollinea, wildly grown in the United Arab Emirates (UAE). The T. apollinea plant was collected, dried, and the leaves were separated. The leaves were ground and extracted. The dried extract was subjected to successive chromatography to identify unique phytochemicals with a special pharmacological activity. The activity of the compound was validated by homology modeling and molecular docking studies. A novel steroidal compound (ergosta-6, 8(14), 22, 24(28)-tetraen-3-one) was isolated and named TNS. In silico target identification of TNS revealed a high structural similarity with the Candida 14-α-demethylase enzyme substrate. The compound exhibited a significant anti-Candida activity, specifically against the multi-drug-resistant Candida auris at MIC50, 16 times less than the previously reported prenylated flavonoids and 5 times less than the methanol extract of the plant. These findings were supported by homology modeling and molecular docking studies. TNS may represent a new class of Candida 14-α-demethylase inhibitors.

7.
Front Genet ; 12: 730599, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35178065

RESUMEN

To estimate gene expression in a reliable manner, quantitative real-time polymerase chain reaction data require normalisation using a panel of stably expressed reference genes (RGs). To date, information on an appropriate panel of RGs in cattle populations reared at cold arid high-altitude hypoxia and hot arid tropical normoxia environments is not available. Therefore, the present study was carried out to identify a panel of stably expressed RGs from 10 candidate genes (GAPDH, RPL4, EEF1A1, RPS9, HPRT1, UXT, HMBS, B2M, RPS15, and ACTB) in peripheral blood mononuclear cells (PBMCs) of cattle populations reared at cold arid high-altitude hypoxia and hot arid normoxia environments. Four different statistical algorithms: geNorm, NormFinder, BestKeeper, and RefFinder were used to assess the stability of these genes. A total of 30 blood samples were collected: six adult heifers each of Ladakhi (LAC) and Holstein Frisian crosses (HFX) and 4 Jersey (JYC) cows from cold arid high-altitude hypoxia environments (group I) and five adult heifers each of Sahiwal (SAC), Karan Fries (KFC), and Holstein Friesian (HFC) cows from hot arid normoxia environments (group II). Combined analysis of group I and group II resulted in identification of a panel of RGs like RPS9, RPS15, and GAPDH that could act as a useful resource to unravel the accurate transcriptional profile of PBMCs from diverse cattle populations adapted to distinct altitudes.

8.
Indian J Microbiol ; 49(1): 60-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23100751

RESUMEN

Phosphate solubilizing fungi (PSF) were enumerated in 78 rhizosphere soil samples collected from various sites of Bhavnagar district with agro climatic zone of hot, semi-arid region of Gujarat. 81% of samples were inhabited with indigenous PSF; the count varied ranging from 0.01 to 90 × 10(3) PSF g(-1). PSF population in the rhizosphere soils were maximal at pH 7.4-8.4, electrical conductivity (EC) 1.2 dS m(-1) wherein PSF population decreased with a rise in EC. Optimal moisture content ranged ≤10-30% where the abundance of PSF always decreased with increase in moisture levels while suitable organic matter content ranged from ≤0.5-4.5%. Available P range 100-300 mg kg(-1) was the most suitable for occurrence of PSF as being noticed from number of soil samples harboring them in rhizosphere soils. Amongst the various rhizosphere soil properties studied, a highly signifi cant positive correlation was established between PSF and soil available P as well as pH. A signifi cant positive association observed between total fungal population and organic matter as well as soil available P. Both abundance and number of PSF were more pronounced in descending order in plant covers: oilseeds, flowers, orchards, vegetables, pulses and cereals.

9.
Saudi J Biol Sci ; 24(7): 1470-1474, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30174491

RESUMEN

Nectar is used as raw material for the production of honey and as significant reward in the relationship between bees and plants during pollination. Therefore, it is important to investigate its abundance, dynamics and associated governing factors. Weather conditions are known to influence nectar production, and predicted climate changes may be responsible for future declining in total yield from beekeeping activities. We investigated nectar production as total soluble solids (TSS) of well-known species for honey production, Ziziphus nummularia in a hot-arid environment of Saudi Arabia. Data on nectar samples from bagged flowers of different stages during two blooming seasons, 2013 and 2015 were collected on weekly bases, and the data were correlated with weather conditions (temperature, relative humidity, and wind). A significant difference in TSS amount has been obtained, with 1-day old flowers displaying the higher content. TSS production was varied along the different day intervals, for both years, with a peak of production in the afternoon. In our results, nectar production was not correlated to temperature and wind, but was significantly negatively correlated with relative humidity. According to the current and future weather forecasting conditions, understanding of the relationship between weather conditions and nectar availability turned out to be important predictive information that may be interpreted into an economic projection of incomes from beekeeping activities.

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