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1.
Braz. j. biol ; 84: e253436, 2024. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1355870

RESUMEN

Abstract The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus' survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores' size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.


Resumo A esporulação de Didymella bryoniae in vitro é de grande importância para estudos que requerem inóculo puro e em grandes quantidades. Assim, os objetivos deste estudo foram identificar a melhor condição para esporulação de D. bryoniae combinando diferentes espectros de luz (luz UV-A ou UV-B, luz branca e escuro contínuo) com distintos meios de cultura (PDA, V8, ML e PDAB) e, avaliar a sobrevivência do fungo armazenado a -20°C ao longo do tempo. As amostras de fungo só esporularam quando submetidas ao tratamento com luz UV-B, independentemente do meio de cultura. Maior aparecimento de esporos do tipo conídio foi observado no meio PDAB, e a menor produção ocorreu no meio ML. Estruturas reprodutivas, como peritécios e picnídeos, foram observadas em todos os meios de cultura. No entanto, houve uma variação considerável na quantidade de cada estrutura entre os diferentes meios de cultura. Os meios ML e V8 apresentaram maior número de peritécios e os meios PDA e PDAB apresentaram maior proporção de picnídeos em relação aos peritécios. A duração do armazenamento a -20°C não afetou o crescimento micelial ou a taxa de crescimento micelial. Em conclusão, a luz UV-B é essencial para a esporulação de D. bryoniae in vitro. Além disso, a composição do meio de cultura influencia o tipo de estrutura fúngica produzida, bem como o tamanho e a quantidade dos esporos. O congelamento a -20°C é uma técnica eficiente que pode ser usada para armazenar D. bryoniae por pelo menos cinco meses sem perda de viabilidade


Asunto(s)
Ascomicetos , Esporas Fúngicas , Temperatura , Micelio
2.
Braz. j. biol ; 84: e252845, 2024. graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1355877

RESUMEN

Abstract This study aimed to evaluate whether skeletal development of the Pantanal Caiman (Caiman yacare) is similarly influenced by temperature variation and controlled increases in embryo motility. All eggs were incubated at 90% humidity and 29 °C for the first 45 days. Thereafter, the incubation temperature was either maintained at 29 °C and embryos were treated with 4-aminopyridine (4-AP) on days 46, 47, 48, and 49 (Group I, 29 °C 4-AP, n = 15); maintained at 29 °C (n = 14; Group II); or at 33 °C (n = 14, Group III). Embryonic movement was measured using an Egg Buddy® digital monitor on days 30, 35, 42, 49, 56, and 60, at which point embryos were euthanized and samples were collected for analysis. No differences were observed between groups with varying incubation temperatures. In contrast, embryonic motility was greater in embryos treated with 4-AP (P < 0.001) on day 49, and this was associated with higher proportions of snout-vent and hand lengths. This study demonstrates for the first time that pharmacologically induced increases in embryo motility result in phenotypic changes to the proportion of elements during prenatal ontogeny, thereby effectively altering the adaptation of the species to specific environments.


Resumo Este estudo objetivou avaliar os efeitos da temperatura e motilidade embrionária sobre o desenvolvimento esquelético de jacaré-do-pantanal (Caiman yacare). Os ovos foram incubados com 90% de umidade e empregou-se a temperatura de 29°C por 45 dias. Após, para a incubação do Grupo I a temperatura continuou em 29°C, mas associou-se à injeção de 4-aminopiridina (29°C-4AP, n = 15) aplicada nos dias 46, 47, 48 e 49, do Grupo II permaneceu em 29°C (n = 14) e do Grupo III elevou-se para 33°C (n = 14). A movimentação foi mensurada através do monitor digital Egg Buddy® nos dias 30, 35, 42, 49, 56 e 60 dias. Aos 60 dias, os embriões foram eutanasiados e coletadas amostras embrionárias. Na análise estatística não foram observadas diferenças entre os grupos para o fator temperatura sobre a motilidade embrionária no desenvolvimento esquelético. Em contraste, a motilidade evidenciou diferença estatística no dia 49 para o Grupo I (P < 0,001) e apresentou maiores proporções de nariz e mão. Esses dados demonstraram pela primeira vez que o aumento na motilidade, induzidos farmacologicamente resultam em divergências fenotípicas na proporção de segmentos anatômicos durante a ontogenia pré-natal, podendo alterar efetivamente a adaptação dos animais em ambientes específicos.


Asunto(s)
Animales , Caimanes y Cocodrilos , Temperatura
3.
Braz. j. biol ; 83: e245206, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339387

RESUMEN

Abstract A huge amount of rice cultivation and consumption occur in Asia particularly in Pakistan and China. However, multiple abiotic stresses especially high and low-temperature proved to be a substantial threat for rice production ultimately risks for food security. To overcome various types of abiotic stress; seed priming is among the effective approaches to improve the rice seed germination and growth vigor. Therefore, the present study was planned to evaluate physiological and biochemical modifications in Chinese and Pakistani rice varieties by Qiangdi 863 biological assistant growth apparatus nano treated water (NTW), Osmopriming Calcium chloride (CaCl2), redox priming hydrogen peroxide (H2O2) and hormonal priming by Salicylic acid (SA) under temperature stress conditions. The experiment was performed with completely randomize design conditions. Five rice varieties, nomenclature as Zhongzoa 39, (Chinese rice variety) KSK 133, KS 282, Super basmati and PK 1121 aromatic (Pakistani rice variety) were sown under low temperature (LT) (17ºC), optimal temperature (OT) 27ºC and high temperature (HT) 37ºC conditions. The present study indicated that nanopriming were the most effective treatments increased Germination Energy Percentage (GEP) (96.1, 100, 100%), Speed of Germination (SG) (27.2, 35.45, 37.1), Final Germination Percentage (FGP) (98.2, 99.1, 99.4%), Seedling Dry Weight Biomass (DWB) (0.1, 0.137, 0.14g), Total Chlorophyll Content (0.502, 13.74, 15.21), antioxidant enzymes Superoxide Dismutase (SOD)(3145, 2559, 3345 µg-1FWh-1), Catalase (CAT) (300, 366, 3243 µg-1FWh-1) and decreased Malondialdehyde (MDA) (6.5, 12.2, 6.5 µmol g-1 FW) for Zhongzao 39 and KSK 133 rice varieties under low (LT+NTW), optimal temperature (OP+NTW) and high temperature (HT+NTW) stress., Therefore, nano-priming is recommended to cope with the high and low-temperature stress conditions along with improved productivity of rice.


Resumo Cultivo e consumo de arroz ocorrem em grandes quantidades na Ásia, particularmente no Paquistão e na China. No entanto, vários estresses abióticos, especialmente de alta e baixa temperatura, provaram ser uma ameaça considerável para a produção de arroz, em última análise, riscos para a segurança alimentar. Para superar vários tipos de estresse abiótico, o priming de sementes está entre as abordagens eficazes que melhoram a germinação e o vigor de crescimento das sementes de arroz. Portanto, o presente estudo foi planejado para avaliar as modificações fisiológicas e bioquímicas em variedades de arroz chinês e paquistanês por Qiangdi 863, aparelho assistente biológico de crescimento com água nanotratada (NTW), Osmopriming cloreto de cálcio (CaCl2), peróxido de hidrogênio redox (H2O2) e priming hormonal por ácido salicílico (SA) em condições de estresse de temperatura. O experimento foi realizado em condições de delineamento inteiramente ao acaso. Cinco variedades de arroz, nomenclaturas como Zhongzoa 39 (variedade de arroz chinês), KSK 133, KS 282, Super basmati e PK 1121 aromático (variedade de arroz do Paquistão) foram semeadas sob baixa temperatura (LT) (17 ºC), temperatura ótima (OT) 27 ºC e condições de alta temperatura (HT) 37 ºC. O presente estudo indicou que nanocondicionamento foi o tratamento mais eficaz: aumento da porcentagem de energia de germinação (GEP) (96,1%, 100%, 100%), velocidade de germinação (SG) (27,2, 35,45, 37,1), porcentagem de germinação final (FGP) (98,2%, 99,1%, 99,4%), biomassa de peso seco de mudas (DWB) (0,1 g, 0,137 g, 0,14 g), conteúdo total de clorofila (0,502, 13,74, 15,21), enzimas antioxidantes superóxido dismutase (SOD) (3145, 2559, 3345 µg-1FWh- 1), catalase (CAT) (300, 366, 3243 µg-1FWh-1) e malondialdeído diminuído (MDA) (6,5, 12,2, 6,5 µmol g-1 FW) para as variedades de arroz Zhongzao 39 e KSK 133 sob baixo (LT + NTW), temperatura ótima (OP + NTW) e estresse de alta temperatura (HT + NTW). Portanto, o nanopriming é recomendado para lidar com as condições de estresse de alta e baixa temperatura, juntamente com a produtividade aprimorada do arroz.


Asunto(s)
Oryza , Semillas , Estrés Fisiológico , Temperatura , Germinación , Plantones , Peróxido de Hidrógeno
4.
Braz. j. biol ; 83: e250879, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339383

RESUMEN

Abstract In the state of São Paulo, the main sugarcane producing region of the world, two species of scale insects have frequently occurred, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) and Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). To map the distribution and abundance of these species, 17 sugarcane producing fields, distributed in six mesoregions in São Paulo, were evaluated in August 2017 and, January, February, June and July 2018 during the ripening phase. The study on the seasonality of these species, by the presence or absence of the scale insects during the phenological cycle of the plant, was conducted between August 2017 and July 2018 in two sugarcane producing fields in the municipality of Jaboticabal, São Paulo, Brazil. The presence of S. sacchari was found in all the analyzed locations, and A. takahashii in twelve. Both scale insects showed significant difference of infestation in the node's region of the stems during the ripening phase in one of the studied locations. The aclerdid presented significant difference by infestation in one site during the ripening phase of the plant. The pseudococcid infested a greater number of nodes in the following phases of development; vegetative, grand growth and ripening in both studied areas, but it was in one site during the ripening phase that presented the greatest difference. Although the pink sugarcane mealybug was more abundant than A. takahashii in both studies, there were no patterns of relationships between the numbers of individuals to geographical locations and temperature.


Resumo No estado de São Paulo, principal região produtora de cana-de-açúcar do mundo, duas espécies de cochonilhas têm ocorrido frequentemente, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) e Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). Para mapear a distribuição e abundância destas espécies, 17 regiões produtoras de cana-de-açúcar, distribuídas em seis mesorregiões de São Paulo, foram avaliadas em agosto de 2017 e janeiro, fevereiro, junho e julho de 2018, durante a fase de maturação. O estudo da sazonalidade destas espécies, pela presença ou ausência das cochonilhas durante o ciclo fenológico da planta, foi conduzido entre agosto de 2017 e julho de 2018 em duas regiões produtoras de cana-de-açúcar no município de Jaboticabal, São Paulo, Brasil. Saccharicoccus sacchari foi encontrada em todas as localidades analisadas, e A. takahashii em 12. Ambas cochonilhas mostraram diferença significativa de infestação na região dos nós dos colmos durante a fase de maturação em uma das localidades estudadas. O aclerdídeo apresentou diferença significativa pela infestação em uma localidade durante a fase de maturação da planta. O pseudococcídeo infestou um grande número de nós nas seguintes fases de desenvolvimento; perfilhamento, crescimento vegetativo e maturação em ambas áreas estudadas, mas foi em uma localidade durante a fase de maturação que apresentou a maior diferença. Embora a cochonilha rosada da cana-de-açúcar foi mais abundante do que A. takahashii em ambos estudos, não houve padrões de relações entre o número de indivíduos com a localização geográfica e temperatura.


Asunto(s)
Humanos , Animales , Saccharum , Hemípteros , Temperatura , Brasil , Productos Agrícolas
5.
Braz. j. biol ; 83: e243629, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1285611

RESUMEN

Abstract As an important enzyme, xylanase is widely used in the food, pulp, and textile industry. Different applications of xylanase warrant specific conditions including temperature and pH. This study aimed to carry out sodium alginate beads as carrier to immobilize previous reported mutated xylanase from Neocallimastix patriciarum which expressed in E. coli, the activity of immobilization of mutated xylanase was elevated about 4% at pH 6 and 13% at 62 °C. Moreover, the immobilized mutated xylanase retained a greater proportion of its activity than the wide type in thermostability. These properties suggested that the immobilization of mutated xylanase has potential to apply in biobleaching industry.


Resumo Como importante enzima, a xilanase é amplamente utilizada na indústria alimentícia, de celulose e têxtil. Diferentes aplicações de xilanase garantem condições específicas, incluindo temperatura e pH. Este estudo teve como objetivo realizar grânulos de alginato de sódio como carreador para imobilizar xilanase mutada relatada anteriormente de Neocallimastix patriciarum que expressa em E. coli, a atividade de imobilização da xilanase mutada foi elevada em cerca de 4% em pH 6 e 13% a 62 °C. Além disso, a xilanase mutada imobilizada reteve uma proporção maior de sua atividade do que o tipo amplo em termoestabilidade. Essas propriedades sugerem que a imobilização da xilanase mutada tem potencial para aplicação na indústria de biobranqueamento.


Asunto(s)
Neocallimastix , Temperatura , Escherichia coli/genética
6.
Braz. j. biol ; 83: e243874, 2023. graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1285606

RESUMEN

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.


Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.


Asunto(s)
Bacillus/metabolismo , Bacillus pumilus/metabolismo , Aguas del Alcantarillado , Temperatura , Fibras de la Dieta , Endo-1,4-beta Xilanasas/metabolismo , Fermentación , Concentración de Iones de Hidrógeno
7.
Commun Biol ; 5(1): 164, 2022 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-35210545

RESUMEN

Quantification of system dynamics is a central aim of mathematical modelling in biology. Defining experimentally supported functional relationships between molecular entities by mathematical terms enables the application of computational routines to simulate and analyse the underlying molecular system. In many fields of natural sciences and engineering, trigonometric functions are applied to describe oscillatory processes. As biochemical oscillations occur in many aspects of biochemistry and biophysics, Fourier analysis of metabolic functions promises to quantify, describe and analyse metabolism and its reaction towards environmental fluctuations. Here, Fourier polynomials were developed from experimental time-series data and combined with block diagram simulation of plant metabolism to study heat shock response of photosynthetic CO2 assimilation and carbohydrate metabolism in Arabidopsis thaliana. Simulations predicted a stabilising effect of reduced sucrose biosynthesis capacity and increased capacity of starch biosynthesis on carbon assimilation under transient heat stress. Model predictions were experimentally validated by quantifying plant growth under such stress conditions. In conclusion, this suggests that Fourier polynomials represent a predictive mathematical approach to study dynamic plant-environment interactions.


Asunto(s)
Proteínas de Arabidopsis , Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Hojas de la Planta , Sacarosa/metabolismo , Temperatura
8.
Ying Yong Sheng Tai Xue Bao ; 33(3): 757-764, 2022 Mar.
Artículo en Chino | MEDLINE | ID: mdl-35524529

RESUMEN

Global changes caused by the increases of atmospheric CO2 concentration and temperature have important effects on soil biogeochemical processes. The synthesis and release of volatile halogenated organic compounds (VOXs) is an important pathway for soil to participate in the global material cycle and energy flow. In this study, Schima superba and Cunninghamia lanceolata seedlings in the southern subtropics were selected as the research objects. Four treatments, including control (CK), elevated CO2 concentration (EC), elevated temperature (ET) and elevated both factors (EC+ET) were set up. The effects of EC and ET on soil VOXs formation were studied by an open-top chamber system coupled with a purging and trapping gas chromatography/mass spectrometry. The results showed that VOXs content in the soil of S. superba seedlings was 0.065-0.252 ng·g-1, which was higher than that of C. lanceolata (0.038-0.136 ng·g-1). At the EC, ET and EC+ET treatments, VOXs contents were reduced in soils of both species. The effect of ET was the most significant, with the decrease rates of 74.2% and 72.1% in both soils, respectively. The change of VOXs content with increasing temperature mainly attributed to the changes of soil moisture and nitrogen content. The content of VOXs in the soils of S. superba seedlings decreased more than that of C. lanceolata under different treatments. In CK, EC, ET and EC+ET treatment, bromodichloromethane (BDCM) (27.5%, 36.7%, 32.9%, 32.6%) and tetrachloromethane (TCM) (9.0%, 16.8%, 22.7%, 15.8%) were the main VOXs in the soil of S. superba seedlings, respectively, while BDCM and dibromomethane (DBM) were the main VOXs in the soil of C. lanceolata seedlings. BDCM accounted for 31.9%, 38.2%, 40.9% and 37.2% of the VOXs content in each treatment, and DBM accounted for 17.9%, 16.5%, 19.2% and 16.0% of the VOXs content, respectively. Simulating elevated atmospheric CO2 concentration and temperature was conducive to more comprehensive reflection of the ecological effect of global climate change, and it could provide data support for improving the VOCs flux model.


Asunto(s)
Cunninghamia , Theaceae , Compuestos Orgánicos Volátiles , Dióxido de Carbono , Plantones , Suelo/química , Temperatura
9.
Environ Monit Assess ; 194(6): 409, 2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35524889

RESUMEN

Land use/land cover (LULC) changes due to urban growth on the regional scale affect land surface temperature (LST). The present study aims to assess the LULC changes and their impact on LST over Mardan and Charsadda districts of Khyber Pakhtunkhwa (KP), Pakistan, in the period from 1990 to 2019. Landsat satellite (TM& ETM +) datasets in the period from 1990 to 2010 and Sentinel-2 images from 2016 to 2019 were used in this study. All the datasets were pre-processed and the LULC types were classified by maximum likelihood classification algorithm. The vegetation degradation was computed from normalized difference vegetation index (NDVI), and the LST was derived based on the LULC changes. The results showed that the overall accuracy of LULC classification was 87.84%. Dramatic LULC changes were observed during the last three decades, where the vegetation degradation area was decreased from 1307.8 (59.27%) to 1147.6 km2 (52.1%) and the barren land area increased from 816.6 (37.07%) to 961.4 km2 (42.64%). Similarly, the built-up area has also increased from 57.2 (2.5%) to 104.3 km2 (4.73%) in the years 1990 and 2019, respectively. These variations in LULC types have significantly influenced the LST from 1990 to 2019; specifically, the LST of built-up area, barren land, and vegetation cover increased from 20.1 to 32.1 °C, 21.5 to 35.5 °C, and 17.1 to 28.2 °C, respectively. The regression line plotted defines that the LST has a negative correlation with NDVI and a positive correlation with normalized difference of built-up index (NDBI). In particular, the vegetation and land covers dramatically transformed to barren land and/or to urban development over the study area in the period from 1990 to2019, which has severely affected the LST and the natural resources of the study area. Therefore, our study will be very helpful for managing the rapid environmental changes and urban planning.


Asunto(s)
Monitoreo del Ambiente , Remodelación Urbana , Monitoreo del Ambiente/métodos , Pakistán , Temperatura , Urbanización
10.
PLoS One ; 17(5): e0268195, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35511880

RESUMEN

Moisture evolution in Central Asia including Northwest China shows less similarity with its surroundings and attracts a growing number of studies. In this study, a well-dated thick lacustrine sequence is chosen in Northwest China and detailed geochemical analysis is conducted during the Middle Miocene Climate Transition (MMCT, 14-11 Ma). The multi-proxy records (Na2O/Al2O3, CIA, Rb/Sr) revealed that chemical weathering was the strongest during 11.85-11 Ma, the coldest period in 14-11 Ma as evidenced by the global deep-sea oxygen isotope records. Accordingly, we conclude that global climate cooled during MMCT and reached the coldest during 11.85-11 Ma. Thus, the westerly circulation became the strongest during this period, which brought more water vapor to Northwest China and the chemical weathering was significantly improved. On the other hand, the significant decrease in temperature led to the marked weakening of evapotranspiration, and thus the effective humidity was relatively increased. Both aspects contribute greatly to the significant enhancement of chemical weathering in eastern Central Asia. This weathering history of the sediments in the northeastern Tibetan Plateau is of great scientific significance to understanding tectonism and climate change in Asia during MMCT.


Asunto(s)
Cambio Climático , Asia , China , Lejano Oriente , Temperatura
11.
PLoS One ; 17(5): e0267481, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35503764

RESUMEN

To improve the prediction accuracy of temperature and humidity in typical Chinese solar greenhouses, this paper proposed a new longwave/shortwave radiation modeling method using bond graph. This model takes into account sun position, useful incoming solar radiation model, sky longwave radiation model, inside longwave, and shortwave radiation model. The approach solves the problems caused by underestimating the effects of longwave radiation on night temperature and relative humidity. The study found that after a period of t = 7.5 h, with the increase of sun altitude angle, the internal temperature was significantly affected by the temperature rise of outside environment on sunny day. The sun altitude angle gradually falls over a period of t = 12.5 h (beginning at 12.30 p.m.). The decline in night temperature steadily slowed after a period of t = 20.5 h. On the other hand, the temperature variation has a multi-peak distribution and the warming rate of the CSG slows down on cloudy days. Furthermore, a good agreement between the experimental and simulation data were obtained, with a maximum temperature deviation of 2°C and maximum humidity deviation of 5%. The developed model is a universal and valuable approach that can be used for greenhouse climate simulation. Furthermore, it can be used as a support system during decision-making processes to help manage Chinese solar greenhouses more efficiently, which provides several control perspectives on the low-energy greenhouse in the future. This work has also provided several control perspectives on the low energy greenhouse in the future.


Asunto(s)
Energía Solar , Luz Solar , China , Humedad , Temperatura
12.
Ying Yong Sheng Tai Xue Bao ; 33(4): 931-938, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35543044

RESUMEN

As an important part of ecological hydrology, transpiration is the basis for analyzing forest water cycle and healthy growth, and important for forest protection and scientific management. We used thermal diffusion probes (TDP) to continuously monitor sap flow of Picea crassifolia in the Qilian Mountains from 2017 to 2018 to explore water consumption of P. crassifolia, and analyze the main controlling factors for the growth and transpiration of spruce. The results showed that the instantaneous change of P. crassifolia sap flow showed a single-peak curve in sunny days, a multi-peak or double-peak curve in cloudy days, and basically no obvious regularity in rainy days. The sap flow density of Qinghai spruce was consistent with the dynamics of solar radiation. The sap flow started earlier and ended later on sunny days, and lasted for 12 to 14 hours. Due to the high altitude (2700 m), low air temperature, and low vapor pressure difference (VPD) in this area, the overall sap flow density was low, with an average of (0.86±0.49) kg·d-1. On the hourly scale, the instantaneous rate of sap flow was significantly affected by solar radiation and VPD. On the daily scale, soil temperature and soil moisture content of the 0-40 cm layer were significantly related to sap flow density. The spruce sap flow density decreased with the decreases of solar radiation, air temperature, and VPD. In the high-altitude forest area of Qilian Mountains, lower soil and air temperature as well as lower VPD and solar radiation were the causes of low sap flow in Picea crassifolia in this area.


Asunto(s)
Picea , China , Bosques , Transpiración de Plantas , Suelo , Temperatura , Árboles , Agua/análisis
13.
BMJ Open Qual ; 11(2)2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35500935

RESUMEN

BACKGROUND: Hypothermia is a common problem that is associated with increased mortality and morbidity among preterm infants, especially in China. The objective of this study was to evaluate the efficacy of a targeted quality improvement (QI) project that applied hypothermia prevention measures for very-low-birth-weight (VLBW) infants in three tertiary neonatal intensive care units (NICUs) in China. PROBLEM: Between January 2018 and December 2018, we conducted a prospective analysis and found that the incidence of AH was 88.2% among VLBW infants. METHODS: The study enrolled preterm infants born at less than 32 weeks' gestation with a VLBW of less than 1500 g who were delivered at three academic tertiary-care hospitals between January 2018 and December 2019. The primary outcome measure was the incidence of hypothermia. The outcomes of the pre-QI group (1 January-31 December 2018) were compared with those of the post-QI group (1 January-31 December 2019). INTERVENTIONS: Based on the literature, our preliminary findings and the needs of each unit, a temperature bundle that included a transport incubator, prewarmed hats, polyethylene wrap, team training and education, and temperature documentation and workflows were implemented in consecutive plan-do-study-act cycles. RESULTS: Of the 530 VLBW infants, 235 infants (36.9%) belonged to the pre-QI group, and 295 infants (46.4%) belonged to the post-QI group. The incidence of hypothermia decreased significantly, from 92.3% to 62% (p<0.001), and the mean body temperature on admission to the NICU increased significantly, from 35.5°C to 36°C±0.7°C (p<0.001). There was one case of hyperthermia during the study period. Infants in the post-QI group had a lower mortality rate (16.1% vs 8.8%, p=0.01). CONCLUSIONS: Targeted interventions can dramatically reduce admission hypothermia and improve the outcome of VLBW infants in China. TRIAL REGISTRATION NUMBER: Chi CTR 1900020861.


Asunto(s)
Hipotermia , Humanos , Hipotermia/epidemiología , Hipotermia/prevención & control , Lactante , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Temperatura
14.
Nat Commun ; 13(1): 2519, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534467

RESUMEN

Floating ice shelves buttress inland ice and curtail grounded-ice discharge. Climate warming causes melting and ultimately breakup of ice shelves, which could escalate ocean-bound ice discharge and thereby sea-level rise. Should ice shelves collapse, it is unclear whether they could recover, even if we meet the goals of the Paris Agreement. Here, we use a numerical ice-sheet model to determine if Petermann Ice Shelf in northwest Greenland can recover from a future breakup. Our experiments suggest that post-breakup recovery of confined ice shelves like Petermann's is unlikely, unless iceberg calving is greatly reduced. Ice discharge from Petermann Glacier also remains up to 40% higher than today, even if the ocean cools below present-day temperatures. If this behaviour is not unique for Petermann, continued near-future ocean warming may push the ice shelves protecting Earth's polar ice sheets into a new retreated high-discharge state which may be exceedingly difficult to recover from.


Asunto(s)
Cubierta de Hielo , Elevación del Nivel del Mar , Clima , Congelación , Temperatura
15.
Sci Rep ; 12(1): 7534, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534513

RESUMEN

We used observational data collected during a mark-recapture study that generated a total of 7503 captures of 6108 unique individuals representing three endangered butterfly species to quantify inter-and intraindividual variation in temperature utilization and examine how activity patterns vary according to season, time of day, and ambient temperature. The Marsh Fritillary, the Apollo, and the Large Blue differed in utilized temperatures and phenology. Their daily activity patterns responded differently to temperature, in part depending on whether they were active in the beginning, middle or end of the season, in part reflecting interindividual variation and intraindividual flexibility, and in part owing to differences in ecology, morphology, and colouration. Activity temperatures varied over the season, and the Apollo and the Large Blue were primarily active at the highest available ambient temperatures (on the warmest days and during the warmest part of the day). The Marsh Fritillary was active early in the season and decreased activity during the highest temperatures. The relationship between individual lifespan and the average temperature was qualitatively different in the three species pointing to species-specific selection. Lifespan increased with an increasing range of utilized temperatures in all species, possibly reflecting that intra-individual flexibility comes with a general survival benefit.


Asunto(s)
Mariposas Diurnas , Animales , Cambio Climático , Humanos , Estaciones del Año , Especificidad de la Especie , Temperatura
16.
Sci Rep ; 12(1): 7564, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534597

RESUMEN

Pectate lyase is a hydrolytic enzyme used by diverse industries to clarify food. The enzyme occupies a 25% share of the total enzyme used in food industries, and their demand is increasing gradually. Most of the enzymes in the market belong to the fungal origin and take more time to produce with high viscosity in the fermentation medium, limiting its use. The bacteria belonging to the genus Bacillus have vast potential to produce diverse metabolites of industrial importance. The present experiment aimed to isolate pectate lyase-producing bacteria that can tolerate an alkaline environment at moderate temperatures. Bacillus subtilis PKC2, Bacillus licheniformis PKC4, Paenibacillus lactis PKC5, and Bacillus sonorensis ADCN produced pectate lyase. The Paenibacillus lactis PKC5 gave the highest protein at 48 h of incubation that was partially purified using 80% acetone and ammonium sulphate. Purification with 80% acetone resulted in a good enzyme yield with higher activity. SDS-PAGE revealed the presence of 44 kDa molecular weight of purified enzyme. The purified enzyme exhibits stability at diverse temperature and pH ranges, the maximum at 50 °C and 8.0 pH. The metal ions such as Mg2+, Zn2+, Fe2+, and Co2+ significantly positively affect enzyme activity, while increasing the metal ion concentration to 5 mM showed detrimental effects on the enzyme activity. The organic solvents such as methanol and chloroform at 25% final concentration improved the enzyme activity. On the other hand, detergent showed inhibitory effects at 0.05% and 1% concentration. Pectate lyase from Paenibacillus lactis PKC5 had Km and Vmax values as 8.90 mg/ml and 4.578 µmol/ml/min. The Plackett-Burman and CCD designs were used to identify the significant process parameters, and optimum concentrations were found to be pectin (5 gm%) and ammonium sulphate (0.3 gm%). During incubation with pectate lyase, the clarity percentage of the grape juice, apple juice, and orange juice was 60.37%, 59.36%, and 49.91%, respectively.


Asunto(s)
Acetona , Álcalis , Sulfato de Amonio , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Paenibacillus , Polisacárido Liasas/metabolismo , Temperatura
17.
Sci Rep ; 12(1): 7535, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534636

RESUMEN

Despite substantial efforts to control locusts they remain periodically a major burden in Africa, causing severe yield loss and hence loss of food and income. Distribution maps indicating the value of the basic reproduction number R0 was used to identify areas where an insect pest can be controlled by a natural enemy. A dynamic process-based mathematical model integrating essential features of a natural enemy and its interaction with the pest is used to generate R0 risk maps for insect pest outbreaks, using desert locust and the entomopathogenic fungus Metarhizium acridum (Synn. Metarhizium anisoliae var. acridum) as a case study. This approach provides a tool for evaluating the impact of climatic variables such as temperature and relative humidity and mapping spatial variability on the efficacy of M. acridum as a biocontrol agent against desert locust invasion in Africa. Applications of M. acridum against desert locust in a few selected African countries including Morocco, Kenya, Mali, and Mauritania through monthly spatial projection of R0 maps for the prevailing climatic condition are illustrated. By combining mathematical modeling with a geographic information system in a spatiotemporal projection as we do in this study, the field implementation of microbial control against locust in an integrated pest management system may be improved. Finally, the practical utility of this model provides insights that may improve the timing of pesticide application in a selected area where efficacy is highly expected.


Asunto(s)
Saltamontes , Metarhizium , Animales , Saltamontes/microbiología , Kenia , Temperatura
18.
PLoS One ; 17(5): e0268253, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35536846

RESUMEN

Thermophiles and hyperthermophiles are those organisms which grow at high temperature (> 40°C). The unusual properties of these organisms have received interest in multiple fields of biological research, and have found applications in biotechnology, especially in industrial processes. However, there are few listings of thermophilic and hyperthermophilic organisms and their relevant environmental and physiological data. Such repositories can be used to standardize definitions of thermophile and hyperthermophile limits and tolerances and would mitigate the need for extracting organism data from diverse literature sources across multiple, sometimes loosely related, research fields. Therefore, we have developed ThermoBase, a web-based and freely available database which currently houses comprehensive descriptions for 1238 thermophilic or hyperthermophilic organisms. ThermoBase reports taxonomic, metabolic, environmental, experimental, and physiological information in addition to literature resources. This includes parameters such as coupling ions for chemiosmosis, optimal pH and range, optimal temperature and range, optimal pressure, and optimal salinity. The database interface allows for search features and sorting of parameters. As such, it is the goal of ThermoBase to facilitate and expedite hypothesis generation, literature research, and understanding relating to thermophiles and hyperthermophiles within the scientific community in an accessible and centralized repository. ThermoBase is freely available online at the Astrobiology Habitable Environments Database (AHED; https://ahed.nasa.gov), at the Database Center for Life Science (TogoDB; http://togodb.org/db/thermobase), and in the S1 File.


Asunto(s)
Archaea , Biotecnología , Archaea/genética , Calor , Filogenia , Temperatura
19.
PLoS One ; 17(5): e0266494, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35587920

RESUMEN

The fluid flow with chemical reaction is one of well-known research areas in the field of computational fluid dynamic. It is potentially useful in the modelling of flow on a nuclear reactor. Motivated by the implementation of the flow in the industrial application, the aim of this study is to explore the time-dependent squeeze flow of magnetohydrodynamic Jeffrey fluid over permeable medium in the influences of Soret and Dufour, heat source/sink and chemical reaction. The presence of joule heating, joule dissipation and radiative heat transfer are analyzed. The flow is induced due to compress of two surfaces. Conversion of partial differential equations (PDEs) into ordinary differential equations (ODEs) is accomplished by imposing similarity variables. Then, the governing equations are resolved using Keller-box approach. The present outcomes are compared with previously outcomes in the literature to validate the precision of present outcomes. Both outcomes are shown in close agreement. The tabular and graphical results demonstrate that wall shear stress and velocity profile accelerate with the surfaces moving towards one another. Moreover, the concentration, temperature and velocity profiles decreasing for the increment of Hartmann numbers and Jeffrey fluid parameters. The impacts of heat generation/absorption, joule dissipation and Dufour numbers enhance the heat transfer rate and temperature profile. In contrast, the temperature profile drops and the heat transfer rate boosts when thermal radiation increases. The concentration profile decelerates, and the mass transfer rate elevates with raise in Soret number. Also, the mass transfer rate rises for destructive chemical reaction and contrary result is noted for convective chemical reaction.


Asunto(s)
Regulación de la Temperatura Corporal , Calor , Fenómenos Físicos , Temperatura
20.
Science ; 376(6595): 860-864, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35587968

RESUMEN

Superconductivity and charge density waves (CDWs) are competitive, yet coexisting, orders in cuprate superconductors. To understand their microscopic interdependence, a probe capable of discerning their interaction on its natural length and time scale is necessary. We use ultrafast resonant soft x-ray scattering to track the transient evolution of CDW correlations in YBa2Cu3O6+x after the quench of superconductivity by an infrared laser pulse. We observe a nonthermal response of the CDW order characterized by a near doubling of the correlation length within ≈1 picosecond of the superconducting quench. Our results are consistent with a model in which the interaction between superconductivity and CDWs manifests inhomogeneously through disruption of spatial coherence, with superconductivity playing the dominant role in stabilizing CDW topological defects, such as discommensurations.


Asunto(s)
Superconductividad , Temperatura
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