Influence Of Different Environmental Factors Research Articles

Non-enzymatic browning reaction of isomaltulose

Isomaltulose is a naturally occurring reducing disaccharide composed of glucose and fructose monomers. It is gaining interest as an alternative sweetener to sucrose in past years. It has been successfully used in various food products like chocolate, breakfast cereals, chewing gums, and dairy products especially, ice cream and yogurt. Nonenzymatic browning reactions in foods continue to be an active area of research because of their important roles in color, flavor and nutritional quality. The present study aimed to investigate the influence of different environmental factors on the non-enzymatic browning reaction of isomaltulose. The formation of colored products as a result of the non-enzymatic browning reaction was monitored. The most significant color change occurs in isomaltulose solution under the studied conditions (pH, temperature and amino component), which is a clear indication of a more intense course of the non-enzymatic browning reaction. The most intense staining was observed at pH 10, t = 80°C with the amino component glycine. It has been found that while glucose solutions are coloured more intensely in the presence of lysine, isomaltulose solutions are coloured more intensely in the presence of glycine. In addition to the type of amino component, the degree of staining is influenced by the pH value and the temperature. The results obtained showed that the use of isomaltulose in the composition of foods, that are subject to heat treatment, will affect the color formation of the final product.

Schinopsis brasiliensis BARK METABOLOMIC PROFILING BASED ON NMR: EVALUATION OF METABOLIC VARIATIONS OF DIFFERENT MICROENVIRONMENT AND SEASONAL PERIODS

Schinopsis brasiliensis Engl. (braúna) is a tree species of the Anacardiaceae family. It is native to Brazil, Paraguay, and Bolivia. It is a candidate for agro-industrial system that can be used to produce phytotherapeutics and bioproducts. However, to comprehensively understand the characteristics of plant within the framework of sustainable development for agro-industries, exploring the chemical and phenotypic diversity of samples from various microenvironments across different collection periods is essential. Accordingly, herein, the influence of different environmental factors and sample collection durations on braúna samples was investigated over several years using multivariate statistical analyses associated with nuclear magnetic resonance (NMR) spectroscopy. Bark samples from different areas and environmental data from different locations were analyzed. Distinct chemical profiles were observed across reserve, forest, and management areas, all marked by elevated sugar levels suggesting water stress adaptation. High radiation and low rainfall correlated with increased sugar and amino acids. Each microenvironment responded uniquely to these environmental conditions. Consequently, plant samples from different microenvironments collected over different periods were observed to respond differently to environmental factors, such as solar radiation and temperature. We correlated the metabolomic data with climatic data evaluating the influence of abiotic factors on the production of metabolites in braúna bark samples.

The influence of environmental conditions and hypochlorous acid (HOCl) fogging on the infectivity of H1N1 influenza virus

The influence of different environmental factors on the infectivity of H1N1 influenza virus was measured. We found less than 1-log reduction when viruses were exposed to NaCl solutions up to 5 M or solutions with pH = 4 through 11 for one hour. The infectivity of the virus was sensitive to the solution temperature. A log reduction ranging from 2 to more than 6 was observed starting at 50 °C and spanning just 3 or 5 for 10- or 30 min exposures, respectively. Drying the virus in media on aluminum or polymer coupons for 48 h resulted in a log reduction of 4 when kept at room temperature, but less than one when kept at 4 °C or -20 °C. Log reduction greater than 6 occurred at room temperature after 3 days, but only 1-log reduction occurred at 4 and -20 °C after 6 days. Drying on different coinage achieved similar results, except for pennies, where more than 6-log reduction was observed after 24 h. HOCl was used to fog the aluminum and polymer surfaces, placed vertically, for 5 and 7.5 min to achieve a log reduction of 4 and for 6.5 respectively. Storage of opened solution containers for 9 months at ambient resulted in a decrease in chlorine concentration from 550 ppm to 240 ppm. Fogging with the old solution was still able to achieve a log reduction of 6.5 after 7.5 min fogging. The study indicates that exposure to common environmental conditions such as a wide pH range, high salinity, and low temperatures has only a minor effect on infectivity. which can persist for more than 5 days when dried on commonly encountered surfaces, allowing accumulation of infectious viral titre. Fogging with HOCl is an effective method of delivering disinfectants to large areas, achieving complete reduction of the viral titer on both horizontal and vertical surfaces.

Adaptability and Germination Characteristics of Volunteer Wheat in China's Main Wheat-Producing Areas.

Volunteer wheat commonly occurs and spreads rapidly in the main wheat-producing areas of China, seriously impacting cultivated wheat production. Limited information is currently available regarding the adaptability and germination traits of volunteer wheat. Therefore, this study's aim was to evaluate the effects of environmental conditions on the germination and emergence of volunteer wheat seeds through laboratory experiments. The results showed that the germination percentages and viability of volunteer wheat were significantly higher than those of cultivated wheat at a low temperature of 5 °C, and they were lower than those of cultivated wheat at high temperatures of above 30 °C. Compared to cultivated wheat, volunteer wheat was able to tolerate higher salinity and lower osmotic potential, especially long-dormancy volunteer wheat. The secondary germination ability of volunteer wheat was higher than that of cultivated wheat after water immersion. Furthermore, volunteer wheat could not emerge normally when the seeding depth was greater than 8 cm, and the emergence ability of the volunteer wheat was weaker than that of the cultivated wheats when the seeding depth was 4-8 cm, which indicates that the deep tillage of cultivated land could effectively prevent the spread of volunteer wheat. This study revealed differences in the germination characteristics of volunteer wheat and cultivated wheat under the influence of different environmental factors, which provides a basis for future studies concerning the control of volunteer wheat.

A Quantitative Analysis for Prioritizing Success Elements in Agile Logistics Applications: The Case of Giresun and Ordu

In today's competitive market conditions, it is not enough to produce high-quality products at the cheapest price. Businesses are expected to deliver the product to the end user round the clock and around the world. One effective way to achieve this is through effective logistics management (Büyükçetin, 2003). Recently, agility has become a frequently discussed topic when it comes to creating an effective logistics management system. The word agility has become synonymous with a strategic response to the survival of businesses in today's competitive environment. However, it should be noted that every business has its unique philosophy and operates under the influence of different environmental factors. Therefore, there is no single agility concept that is suitable for all businesses or every situation (İlhan, 2007). Creating an agile logistics strategy can be achieved not only by minor changes but also by completely differentiating the methods of performing activities (Gunesakaran,1999). The creation of this differentiation depends on various success factors. The success factors of agile logistics considered in this study include: “Managing Change and Uncertainty”, “Flexibility and Responsiveness in Service”, “Increasing the Value Shown to the Customer”, “Information Technologies”, “Flexible Human Resources” and “Building Collaborations Among Service Providers”. These factors play a crucial role in the success of businesses and can increase their competitiveness. The absence of studies in the literature regarding the ranking of the success factors in agile logistics applications points to the important contribution of this study to the literature.To address this research gap, this study aims to rank the success factors of agile logistics practices in logistics firms in Giresun and Ordu provinces. The ranking will be done using the Spherical fuzzy sets based AHP. By prioritizing these success factors, businesses can identify the areas they need to focus on and improve, ultimately enhancing their competitiveness and success in the market.

Phase separation propensity of the intrinsically disordered AB region of human RXRβ

RXRβ is one of three subtypes of human retinoid X receptor (RXR), a transcription factor that belongs to the nuclear receptor superfamily. Its expression can be detected in almost all tissues. In contrast to other subtypes – RXRα and RXRγ – RXRβ has the longest and unique N-terminal sequence called the AB region, which harbors a ligand-independent activation function. In contrast to the functional properties of this sequence, the molecular properties of the AB region of human RXRβ (AB_hRXRB) have not yet been characterized. Here, we present a systematic biochemical and biophysical analysis of recombinant AB_hRXRB, along with in silico examinations, which demonstrate that AB_hRXRB exhibits properties of a coil-like intrinsically disordered region. AB_hRXRB possesses a flexible structure that is able to adopt a more ordered conformation under the influence of different environmental factors. Interestingly, AB_hRXRB promotes the formation of liquid–liquid phase separation (LLPS), a phenomenon previously observed for the AB region of another human subtype of RXR – RXRγ (AB_hRXRG). Although both AB regions seem to be similar in terms of their ability to induce phase separation, they clearly differ in the sensitivity to factors driving and regulating LLPS. This distinct LLPS response to environmental factors driven by the unique amino acid compositions of AB_hRXRB and AB_hRXRG can be significant for the specific modulation of the transcriptional activation of target genes by different subtypes of RXR.89Jx1wwVvjJQ45uAcpVb5SVideo

Characterization of an antimicrobial pentapeptide produced by a drug-sensitive Pseudomonas aeruginosa strain PAST18

The members of the genus Pseudomonas can secrete a wide range of ribosomally encoded antagonistic peptides and proteins, ranging from small microcins to large tailocins. In this study, a drug-sensitive Pseudomonas aeruginosa strain isolated from a high-altitude virgin soil sample showed a broad range of antibacterial activity against Gram-positive and Gram-negative bacteria. The antimicrobial compound, purified by affinity chromatography, ultrafiltration, and high-performance liquid chromatography, showed a molecular weight (M + H)+ of 494.7667 daltons, as revealed by ESI-MS analysis. The MS-MS analysis divulged the compound as an antimicrobial pentapeptide with the sequence NH2-Thr-Leu-Ser-Ala-Cys-COOH (TLSAC) and was further verified by evaluating the antimicrobial activity of the chemically synthesized pentapeptide. The extracellularly released pentapeptide, which is relatively hydrophobic in nature, is encoded in a symporter protein, as appraised from the whole genome sequence analysis of strain PAST18. The influence of different environmental factors was examined to determine the stability of the antimicrobial peptide (AMP), which was also assessed for several other biological functions, including antibiofilm activity. Further, the antibacterial mechanism of the AMP was evaluated by a permeability assay. Overall, the characterised pentapeptide, as revealed in this study, may find use as a potential biocontrol agent in various commercial applications.

Aktivnost inhibitora tripsina u semenu sastrice (Lathyrus sativus L.)

Grass pea (Lathyrus sativus) is a valuable grain legume known for its high protein content and rich essential amino acid profile. Its exceptional characteristics such as drought tolerance, high adaptability to extreme conditions, disease resistance, and low cultivation inputs, make it particularly suitable for cultivation by resource-poor farmers. However, the potential use of grass pea is limited due to the presence of anti-nutritional factors, including protease inhibitors, especially trypsin inhibitor. This study aimed to develop a rapid and reliable method for measuring TI activity in seeds of grass pea and to investigate the influence of genotype and environment on trypsin inhibitor (TI) activity in seeds of grass pea. A set of 25 grass pea accessions from seven European countries was cultivated in Slovenia at the Agricultural Institute of Slovenia, and a set of 12 grass pea accessions from the Serbian gene bank was grown in Serbia at the Institute of Field and Vegetable Crops. The TI activity varied considerably among the grass pea accessions studied, with values ranging from 26.7 to 90.3 TUI/mg. To further evaluate the effects of environmental conditions on TI activity, eight grass pea accessions originating from Serbia were grown in both Slovenia and Serbia. The TI activity of the accessions grown in Slovenia ranged from 26.7 to 81.0 TUI/mg, while the activity of the accessions grown in Serbia ranged from 40.3 to 57.0 TUI/mg. The correlation of TI activity between grass pea accessions grown in Slovenia and those grown in Serbia was 0.39, with genotype diversity being the largest contributor (55.9%). This study provides a valuable insight into the variability of TI activity in grass pea and shows the possible influence of environmental conditions on this trait. However, since the data are only from a one-year field trial, further studies are needed to fully evaluate the influence of different environmental factors on TI activity.

Phytoremediation of 137Cs: factors and consequences in the environment.

Radionuclide contamination is a concerning threat due to unexpected nuclear disasters and authorized discharge of radioactive elements, both in the past and in present times. Use of atomic power for energy generation is associated with unresolved issues concerning storage of residues and contaminants. For example, the nuclear accidents in Chernobyl 1986 and Fukushima 2011 resulted in considerable deposition of cesium (Cs) in soil, along with other radionuclides. Among Cs radioactive variants, the anthropogenic radioisotope 137Cs (t½ = 30.16 years) is of serious environmental concern, owing to its rapid incorporation into biological systems and emission of β and γ radiation during the decaying process. To remediate contaminated areas, mostly conventional techniques are applied that are not eco-friendly. Hence, an alternative green technology, i.e., phytoremediation, should in future be considered and implemented. This sustainable technology generates limited secondary waste and its objectives are to utilize hyper-accumulating plants to extract, stabilize, degrade, and filter the radionuclides. The review highlights plant mechanisms for up-taking radionuclides and influences of different environmental factors involved in the process, while considering its long-term effects.

Influence of environmental factors on seed germination and seedling characteristics of perennial ryegrass (Lolium perenne L.)

Information regarding the germination and seedling growth behavior of a potential weed species is an important tool to manage weeds without the use of agricultural chemicals that cause harmful effects on human health and the environment. A series of experiments were directed to investigate the influence of different environmental factors (temperature, pH, NaCl, moisture stress, and seed burial depth) on germination and seedling emergence of perennial ryegrass (Lolium perenne L.) under controlled conditions. Results suggested that 25 °C is the optimum temperature for maximum germination (95%) and seedling growth of perennial ryegrass, however, a quick decline was observed at 35 °C. Seed germination was unaffected by pH levels ranging from 5 to 10. The 92% seed germination was recorded where no salt stress was applied and germination was reduced by 87% at 250 mMNaCl concentration. Seed germination was unaffected by osmotic potential ranges from 0 to − 0.4 MPa thereafter declined and completely inhibited at − 0.8 or − 1.0 MPa. No seed emerged at the soil surface or a soil depth of 6 or 7 cm and 90% emergence occurred at 1 cmsoil depth. The germination and seedlings parameters like time to initial germination, mean germination time, time taken to 50% germination and germination index, root and shoot length, and fresh and dry weight of root and shoot are significantly affected with the environmental factors. The information obtained in this study will be helpful to develop better management strategies for germination and the emergence of perennial ryegrass in areas where it has the ability to rapidly colonize.

Monitoring Chlorophyll-a concentration in karst plateau lakes using Sentinel 2 imagery from a case study of pingzhai reservoir in Guizhou, China

ABSTRACT Chlorophyll-a concentration (Chla) is an important index for water eutrophication. In this study, retrieval models of Chla were established based on the measured water spectra, spectral response function, measured Chla and the corresponding Sentinel-2 imagery of the Pingzhai Reservoir, the first large-scale trans-regional, trans-basin, and long-distance source reservoir in Guizhou. The retrieved results from 11 Sentinel-2 from 2018 to 2021 were used to analyze the spatiotemporal variations in Chla and the influence of different environmental factors on their spatial differentiation, providing a powerful approach for monitoring Chla in the Pingzhai Reservoir. Our binomial function model based on B8*(B7-B5) of Sentinel-2 yielded acceptable to high fitting accuracies, accounting for 89% of the variation in Chla. Overall, the Chla was relatively low, with a mean value of 10.24 μg/L. Higher Chla were distributed in the catchment area, such as the Nayong River and the dam. Moreover, significant seasonal fluctuations and intra-year changes were observed . Spatio-temporal variations in Chla were influenced by human activities and environmental factors such as Dissolved Oxygen (DO), Total Nitrogen (TN), and Ammoniacal Nitrogen (NH4 +-N). Our work provided compelling evidence that Sentinel-2 could be used for quantitative inversion of Chla in Pingzhai Reservoir.

Corrosion sensitivity analysis of pipelines in CO2 and H2S coexisting environment in the South China Sea

Abstract The purpose of the present work is to investigate the corrosion sensitivity of pipelines of oil and gas wells under complex environmental conditions (i.e., the primary and secondary relationship of the influence of different environmental factors on pipeline corrosion). The orthogonal experiment is introduced to design the experimental scheme. The weight loss method is employed to analyze the average corrosion rate of N80 steel under different environmental conditions. And then the scanning electron microscope is used to explore the surface and cross-section corrosion morphology of the corrosion products. Besides, the components of corrosion products are obtained by the energy spectrum analysis. The research results indicate that H2S partial pressure is the most sensitive factor to the corrosion of N80 pipeline and the influence of CO2 partial pressure on corrosion of N80 pipeline is weaker than Cl− concentration and temperature in the South China Sea. The study can help the oil drilling engineering search for direct and effective corrosion inhibitors under complex environmental conditions.

Genetic and non-genetic parameter estimates for growth traits and Kleiber ratios in Dorper × indigenous sheep

Genetic improvement programme will only be successful when accompanied by a good understanding of the influence of different environmental factors, knowledge of the genetic parameters and the genetic relationships between the traits of interest. This study aimed to evaluate the influence of non-genetic factors on growth traits and Kleiber ratios and to estimate genetic parameters for early growth traits in Dorper × indigenous crossbred sheep. The effects of fixed factors were analysed by the general linear model procedure of statistical analysis system, while the genetic parameters were estimated using a WOMBAT computer program fitted animal model. The overall least-square mean for birth weight (BRW), weaning weight (3MW), six-month weight, nine-month weight, and yearling weight were 3.03 ± 0.02, 14.5 ± 0.18, 20.4 ± 0.26, 24.8 ± 0.31, and 28.3 ± 0.40 kg, respectively. The overall least-square mean for Kleiber ratio from birth to weaning (KR1), weaning to six months, six to nine months and nine months to yearling age were 16.8 ± 0.10, 6.41 ± 0.17, 4.55 ± 0.21 and 3.38 ± 0.20 g/kg of metabolic weight, respectively. The inclusion of maternal genetic effect had a significant influence on BRW, and it explains 20% of the phenotypic variation. The total heritability estimates for BRW, 3MW, birth to weaning average daily weight gain and KR1 were 0.10, 0.14, 0.16 and 0.12, respectively. The phenotypic correlation varied from −0.11 ± 0.05 to 0.98 ± 0.02, whereas the direct genetic correlation ranged from −0.32 ± 0.40 to 0.98 ± 0.17. The mean inbreeding coefficient was 0.105% with an annual rate of 0.02%. The heritability estimates for growth traits and Kleiber ratio suggest that slow genetic progress would be expected from the selection. However, the integration of selection with crossbreeding programme can enhance genetic gain. Therefore, selection should be conducted based on breeding values estimated from multiple information sources to increase the selection response.

Environmental factors driving evapotranspiration over a grassland in a transitional climate zone in China

AbstractThe surface evapotranspiration (ET) process is the key link in the interaction between land and atmosphere. However, the influence of different environmental factors on ET over transitional climate zones and the physical pattern of the interaction between multiple factors remain unclear. Therefore, based on the continuous observation data during the vegetation growing season of a typical grassland in the Semi‐Arid Climate and Environment Observation of Lanzhou University (SACOL) station from 2007 to 2012, the influence pattern of multiple environmental factors on ET over China's transitional climate zone was analysed. Each environmental factor exhibited significant seasonal and interannual variations. The mean value of ET was 1.67 mm day−1. Although the maximum values of sensible heat flux and vapour pressure deficit occurred in April and June, respectively, the maximum values of other environmental factors appeared from July to August. Net radiation, soil moisture, and normalized difference vegetation index (NDVI) were the main controlling factors of ET over the grassland, with correlation coefficients of 0.54, 0.52, and 0.46, respectively. The analysis of multiple environmental factors showed that when soil moisture, wind speed, net radiation, and NDVI reached 0.2 m3 m−3, 2 m s−1, 100 W m−2, and 0.2, respectively, ET varied in contrast with vapour pressure, vapour pressure deficit, and air temperature under the influences of weather processes, land–atmosphere coupling, and drought stress. These findings deepen our understanding of the role of ET in the land–atmosphere coupling process over the transitional climate zone in China.

Quantum, molecular and continuum modeling in nonlinear mechanics of viruses

Introdution. Viruses are a large group of pathogens that have been identified to infect animals, plants, bacteria and even other viruses. The 2019 novel coronavirus SARS-CoV-2 remains a constant threat to the human population. Viruses are biological objects with nanometric dimensions (typically from a few tens to several hundreds of nanometers). They are considered as the biomolecular substances composed of genetic materials (RNA or DNA), protecting capsid proteins and sometimes also of envelopes. Objective. The goal of the present review is to help predict the response and even destructuration of viruses taking into account the influence of different environmental factors, such as, mechanical loads, thermal changes, electromagnetic field, chemical changes and receptor binding on the host membrane. These environmental factors have significant impact on the virus. Materials and methods. The study of viruses and virus-like structures has been analyzed using models and methods of nonlinear mechanics. In this regard, quantum, molecular and continuum descriptions in virus mechanics have been considered. Application of single molecule manipulation techniques, such as, atomic force microcopy, optical tweezers and magnetic tweezers has been discussed for a determination of the mechanical properties of viruses. Particular attention has been given to continuum damage–healing mechanics of viruses, proteins and virus-like structures. Also, constitutive modeling of viruses at large strains is presented. Nonlinear elasticity, plastic deformation, creep behavior, environmentally induced swelling (or shrinkage) and piezoelectric response of viruses were taken into account. Integrating a constitutive framework into ABAQUS, ANSYS and in-house developed software has been discussed. Conclusion. Link between virus structure, environment, infectivity and virus mechanics may be useful to predict the response and destructuration of viruses taking into account the influence of different environmental factors. Computational analysis using such link may be helpful to give a clear understanding of how neutralizing antibodies and T cells interact with the 2019 novel coronavirus SARS-CoV-2.

Aging Behavior of High-Viscosity Modified Asphalt Binder Based on Infrared Spectrum Test.

In the rapid development of sponge city construction in China, porous asphalt pavement has been widely used. The high-viscosity modified asphalt used for porous asphalt pavements is utilised in a complex aging environment. In this study, infrared spectroscopy was used to test the changes in the functional groups of high-viscosity modified asphalt under the influence of ultraviolet radiation intensity, high temperature, and water corrosion conditions. The research results showed that under the influence of several environmental factors, the high-viscosity modified asphalt has no chemical reaction but does undergo physical changes. From the perspective of the functional group index, the carbonyl index is more suitable for evaluating the degree of ultraviolet aging, and the sulfoxide group index is more suitable for evaluating the effect of temperature on aging. The high-viscosity modified asphalt aging kinetic models, established with different functional group indexes as indicators, have different activation energies. The aging kinetic model established with the carbonyl index is more suitable for simulating traditional thermal-oxidative aging. This study provides a better plan to reveal the influence of different environmental factors on the aging performance of high-viscosity modified asphalt under complex environmental conditions.

Multi-scene design analysis of integrated energy system based on feature extraction algorithm

The specific analysis of a region’s energy needs to model and simulate various types of energy, quantify energy information, and clearly and intuitively reflect the energy situation and energy potential of a region. In this paper, according to the input attributes of various energy load forecasting models, the correlation degree of main control factors is analyzed, and the influence degrees of environmental factors on electric power, gas, heating and cooling loads are obtained respectively. Then, convolution neural network is used to extract the feature vectors of comprehensive environmental factors. Finally, according to the given feature vectors, the feature clustering models of various energy loads are established by using K-means clustering algorithm, and the load forecasting results of multi-energy systems are obtained. The errors between the predicted results of various energy loads and the actual load records in the study area are 1.105%, 1.876%, 3.102% and 2.834%, respectively. The load forecasting method based on feature clustering proposed in this paper can effectively extract the influence of different environmental factors on the load forecasting results, and get more accurate load forecasting results.

Gut Microbiota: A Key Regulator in the Effects of Environmental Hazards on Modulates Insulin Resistance.

Insulin resistance is a hallmark of Alzheimer’s disease (AD), type II diabetes (T2D), and Parkinson’s disease (PD). Emerging evidence indicates that these disorders are typically characterized by alterations in the gut microbiota composition, diversity, and their metabolites. Currently, it is understood that environmental hazards including ionizing radiation, toxic heavy metals, pesticides, particle matter, and polycyclic aromatic hydrocarbons are capable of interacting with gut microbiota and have a non-beneficial health effect. Based on the current study, we propose the hypothesis of “gut microenvironment baseline drift”. According to this “baseline drift” theory, gut microbiota is a temporarily combined cluster of species sharing the same environmental stresses for a short period, which would change quickly under the influence of different environmental factors. This indicates that the microbial species in the gut do not have a long-term relationship; any split, division, or recombination may occur in different environments. Nonetheless, the “baseline drift” theory considers the critical role of the response of the whole gut microbiome. Undoubtedly, this hypothesis implies that the gut microbiota response is not merely a “cross junction” switch; in contrast, the human health or disease is a result of a rich palette of gut-microbiota-driven multiple-pathway responses. In summary, environmental factors, including hazardous and normal factors, are critical to the biological impact of the gut microbiota responses and the dual effect of the gut microbiota on the regulation of biological functions. Novel appreciation of the role of gut microbiota and environmental hazards in the insulin resistance would shed new light on insulin resistance and also promote the development of new research direction and new overcoming strategies for patients.

Study on the polarization pathways of macrophages and related diseases

Macrophage is a relatively stable heterogeneous immune cell isolated from monocytes in plasma, which plays a certain role in maintaining stable environment, host defense, phagocytosis and immune information transmission. Under the influence of different environmental factors, macrophages can be polarized into Ml and M2, and this process is reversible. The special phenotype of macrophage polarization can play a role in alleviating or curing the disease, and the polarization process is affected by the stimulation of different signaling pathways [1]. This chapter will review the classical types of macropage polarization, the most important information pathways and regulatory mechanisms, in an attempt to provide a basis for subsequent regulation and the occurrence and progression of lesions.

砒砂岩区植被覆盖度环境驱动因子量化分析——基于地理探测器

PDF HTML阅读 XML下载 导出引用 引用提醒 砒砂岩区植被覆盖度环境驱动因子量化分析——基于地理探测器 DOI: 10.5846/stxb202103020564 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（42077074）；国家重点研发计划（2017YFC0504501） Quantitative analysis of environmental driving factors of vegetation coverage in the Pisha sandstone area based on geodetector Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:砒砂岩区地形破碎，生态环境恶劣，降水量少且以暴雨为主，研究该区植被覆盖变化及环境驱动因子作用机制对区域植被建设具有重要的理论意义。基于1999-2018年的NDVI数据分析了砒砂岩区近20年植被覆盖度时空变化特征，利用了地理探测器方法量化分析了不同环境因子对植被覆盖度的影响。结果表明：1）近20年砒砂岩区平均植被覆盖度为42.3%，时间尺度上1999-2018年区域植被覆盖度呈增加趋势，平均上升幅度为0.086/10 a，空间尺度上植被覆盖度呈现从东南向西北递减的空间分布特征；2）近20年区域植被覆盖整体得到改善要比退化的区域面积大，45.5%的区域面积植被覆盖度极显著增加，主要分布在砒砂岩区东部区域，该区植被覆盖度未来变化趋势将以持续性改善为主，但仍有约41.6%的植被将由改善向退化方向变化；3）降水、土壤水分和气温是影响砒砂岩区植被覆盖空间分布的主导环境因子，且降水同其他环境因子的交互作用对植被覆盖影响最大。 Abstract:The Pisha sandstone area is broken in topography, with little precipitation and mainly rainstorm, the ecological environment in the area is harsh. It is of great theoretical significance for regional vegetation construction to study the dynamic change of vegetation and explore the response characteristics of vegetation coverage to environmental factors. Based on the normalized difference vegetation index (NDVI) from 1999 to 2018, this study analyzed the spatio-temporal change characteristics of vegetation coverage in the Pisha sandstone area. In addition, the geodetector was used to analyze the influence of different environmental factors on the change of vegetation coverage, then we determined the most suitable range and type of each factor to promote vegetation growth. The results show that:1) In the past 20 years, the average vegetation coverage in the Pisha sandstone area was 42.3%. On the time scale, the regional vegetation coverage had an increasing trend from 1999 to 2018, with an average increase of 0.086/10 a. On the spatial scale, the vegetation coverage presents a distribution characteristic of decreasing from southeast to northwest. The vegetation coverage of the three areas changes from large to small in order of soil-covered Pisha sandstone area, sand-covered Pisha sandstone area, and bare Pisha sandstone area. 2) In the past 20 years, the overall improvement of vegetation coverage in the Pisha sandstone area is greater than the degraded area. About 45.5% vegetation coverage of the regional area has increased obviously, mainly in the eastern part of the Pisha sandstone area whereas the significantly reduced areas were scattered in the middle of the bare area. The future trend of vegetation coverage in the Pisha sandstone area will be dominated by continuous improvement, accounting for 50.5% of the total area, mainly distributed in the southern soil-covered Pisha sandstone area. Although the vegetation in this area is showing an overall trend of improvement, it still faces greater challenges. About 41.6% of the vegetation is at risk of changing from improvement to degradation. 3) Precipitation, soil moisture and temperature are the dominant environmental factors that affect the spatial distribution of vegetation coverage in the region, while the slope and aspect have the weakest explanatory power for vegetation coverage. The interaction among environmental factors is dominated by a two-factor enhancement trend. As the dominant climate factor in the spatial distribution of vegetation coverage in this region, precipitation has the greatest influence on vegetation coverage under the interaction with other environmental factors. 参考文献 相似文献 引证文献