Cross-sectional analysis of socioeconomic drivers of PM2.5 pollution in emerging SAARC economies.

Within the intricate interplay of socio-economic, natural and anthropogenic factors, haze pollution stands as a stark emblem of environmental degradation, particularly in the South Asian Association for Regional Cooperation (SAARC) region. Despite significant efforts to mitigate greenhouse gas emissions, several SAARC nations consistently rank among the world's most polluted. Addressing this critical research gap, this study employs robust econometric methodologies to elucidate the dynamics of haze pollution across SAARC countries from 1998 to 2020. These methodologies include the Pooled Mean Group (PMG) and Augmented Mean Group (AMG) estimator, Panel two-stage least squares (TSLS), Feasible Generalized Least Squares (FGLS) and Dumitrescu-Hurlin (D-H) causality test. The analysis reveals a statistically significant cointegrating relationship between PM2.5 and economic indicators, with economic development and consumption expenditure exhibiting positive associations and rainfall demonstrating a mitigating effect. Furthermore, a bidirectional causality is established between temperature and economic growth, both influencing PM2.5 concentrations. These findings emphasize the crucial role of evidence-based policy strategies in curbing air pollution. Based on these insights, recommendations focus on prioritizing green economic paradigms, intensifying forest conservation efforts, fostering the adoption of eco-friendly energy technologies in manufacturing and proactively implementing climate-sensitive policies. By embracing these recommendations, SAARC nations can formulate comprehensive and sustainable approaches to combat air pollution, paving the way for a healthier atmospheric environment for their citizens.

Effects of embryonic thermal manipulation on the immune response to post-hatch Escherichia coli challenge in broiler chicken.

Background and Aim: Thermal manipulation (TM), exposure to mild heat shock during embryogenesis, which is a critical developmental period of broiler chickens, improves tissue stability, oxidative stress response, and immune response during heat stress. Thermal manipulation could be more cost-effective than other methods to boost the immune response. This study aimed to evaluate the impact of TM during embryogenesis, concomitant with an Escherichia coli challenge, on body weight (BW), body temperature (Tb), and splenic mRNA expression of cytokines (Interleukin [IL]-1ß, IL-2, IL-6, IL-8, IL-12, IL-15, IL-16, IL-18, and interferon [IFN]-γ) in poultry. Materials and Methods: A total of 740 fertile eggs were procured from a certified Ross broiler breeder. The eggs were divided into two incubation groups: the control and TM groups. The eggs in the control group were kept at 37.8°C air temperature and 56% relative humidity (RH) during incubation; eggs of the TM group were incubated under standard conditions, except for embryonic days 10-18, during which they were incubated at 39°C and 65% RH for 18 h daily. On the 7th day of incubation, eggs with dead embryos were excluded. After hatching was complete, each group was further subdivided into saline-treated or E. coli-challenged groups. The E. coli (serotype 078 with the dose of 1.5 × 105 colony-forming unit/mL) challenge was performed when the birds were 20 days old. Body weight and Tb measurements were taken on post-hatch days 20, 21, 23, and 25. Splenic mRNA expression of cytokines (IL-1ß, IL-2, IL-6, IL-8, IL-12, IL-15, IL-16, IL-18, and IFN-γ) was analyzed by real-time quantitative polymerase chain reaction. Results: Following the E. coli challenge, the TM-treated group's body performance parameters (BW and Tb) were significantly increased compared with the control group. Body weight was higher in the TM group than in the control group (p < 0.05); Tb was lower in the TM group than in the control group (p < 0.05). The mRNA levels of IL and IFN-γ were more stable and moderately induced in the TM group compared with the control group. Thermal manipulation altered the basal mRNA levels of ILs and IFN-γ and changed their expression dynamics after the E. coli challenge. Conclusion: Thermal manipulation during embryogenesis could boost the immune system response to E. coli.

Does location of the households' matters? Identifying the households' willingness to pay and preference heterogeneity in advancement of vulnerable ecosystem services: An approach of choice experiment.

The present research underlines the need to expand far outside bundling or hierarchical providing strategy that often focuses on a specific habitat or ecosystem and creates a location-based strategy that considers how dependency in other parts of the region with ecosystem functions and processes leads to complements and resources' trade-offs. Thus, for assessment of spatial heterogeneity based on willingness to pay (WTP) for upgrading environmental attributes across Heihe River Basin (HRB), a choice experiment survey was carried out in the entire river basin. The HRB is one of the big inland river in the Northwestern region of China and is selected on basis of its geomorphological and geographical significance. A sum of 1679 individuals were interviewed through choice experiment technique from whole river basin consisting of five main cities and 33 adjoining rural areas. The Random Parameter logit model, Krinsky-Robb technique as well as delta method were applied for the evaluation of spatial heterogeneity and estimation of individual specific WTP, respectively. Spatial heterogeneity is verified among sampled individuals' preferences about upgradation of environmental attributes, such as, observed preferences of individuals' and their varying corresponding WTP amounts for per unit's upgradation in agriculture product quality, greenhouse gases reduction, farmland landscape, and biodiversity, which reflects heterogeneous tastes and preferences of the selected individuals. In addition, the assessed outcomes for identifying the impacts of distance decay through random parameter logit model depicted the vital role of distance influence on respondents' WTP for restoring the degraded environmental attributes, such that among 3 ad hoc distance bands, WTP of those sampled individuals who are in proximity of ≤ 10 km to HRB is more than the rest of the individuals, i.e., individuals living in the range of ≤ 20 km and > 20 km. For instance, WTP for agriculture product quality is 119.147 CNY/year in ≤ 10 km and is higher than the remainders.

Azanza garckeana ameliorates Bisphenol A-induced reproductive toxicities in rabbit bucks.

This study evaluated the ameliorative properties of Azanza garckeana in Bisphenol A-induced reproductive toxicities on weight, spermiogram, serum hormonal profile, sperm DNA integrity, histopathology of testes and brain tissues of rabbit bucks. Twenty-eight rabbit bucks, with live weight of 1.20-2.00 kg and aged 10-18 months. They were randomly divided into four groups of seven bucks each, group A was administered distilled water (1.5 mL) daily for 12 weeks, group B was administered Bisphenol A (100 mg/kg) for 5 consecutive days in a week for a period of 12 weeks, group C was administered Azanza garckeana (500 mg/kg) daily for 12 weeks and group D was pre-dosed with Bisphenol A (100 mg/kg) for 5 consecutive days in a week over 6 weeks period followed by Azanza garckeana (500 mg/kg) daily for another 6 weeks. Mean testicular weights differed significantly (p < 0.05) between group B (4.4 ± 0.23) when compared with groups A (8.0 ± 0.06), C (8.7 ± 0.19) and D (7.1 ± 0.18). There were significant differences (p < 0.05) in the mean reaction time, spermiogram, testosterone, follicle stimulating hormone, luteinising hormone and sperm DNA fragmentation index between Bisphenol A-exposed groups and treatment groups. On histopathology, there was testicular vacuolization, interstitial hemorrhage, reduction in spermatogenic cells following Bisphenol A exposure. There were layers of dense basophilic cells in the pineal and pituitary parenchymas. In conclusion, Bisphenol A has negative effects on reproduction but administration of Azanza garckeana may possess some therapeutic properties that can ameliorate such adverse effects.

Do anthropogenic and natural factors elevate the haze pollution in the South Asian countries? Evidence from long-term cointegration and VECM causality estimation.

Anthropogenic and natural factors lead to substantial environmental degradation. This shift is aligned with the country's overall development, resulting in high demand for energy resources and a dramatic shift in human activities that contribute to haze pollution. Some of the countries in the South Asian region are ranked between one and twenty on the list of countries with the highest levels of PM2.5 pollution. The member countries have taken many steps to tackle global warming, but concern about haze pollution was found limited. Moreover, very little research was conducted on haze pollution, which led us to conduct this research in this region. This study used the panel data from 1998 to 2018 and a set of econometric models like long-term cointegrating relationship, fully modified ordinary least squares, and vector error-correction model Granger causality tests to examine the major drivers like anthropogenic and natural factors that might elevate haze pollution. Furthermore, our empirical results depict that (1) there is a long-term cointegrating relation between haze and the factors studied. (2) Energy consumption, urbanisation, and economic growth are the primary drivers of environmental degradation. (3) Rainfall has the most substantial influence on reducing haze pollution. The study concluded that (a) if the countries continue to develop at the same pace, all factors studied will continue to drive haze pollution to rise. (b) A decrease in PM2.5 pollution requires improvements in regional rainfall through vegetation, reducing reliance on fossil fuel-based energy sources, and increasing environmental education. (c) Slowing down the drive for urbanisation would not be cost-effective in reducing haze pollution in the region in the short run. Thus, reducing haze by adjusting the factors studied would not be easy in the short run and require the careful adoption of long-term policies.

Quantifying the spatial preferences heterogeneity to upgrade the endemic ecological attributes for a cleaner environment: Evaluating the feasibility of benefit transfer among sub-basins of an inland river.

The role of wetlands in the conservation of global biodiversity is very significant due to the provision of various benefits to households. The assessment of these benefits and general public perception in terms of their willingness to pay for restoring the degraded ecosystem services is also heterogeneous because of their spatial preferences. This research employed a choice experiment technique to evaluate willingness to pay of the households to improve the current degraded ecosystem services and assessed benefit transfer among upper, middle and lower sub-basins of Heihe River. The outcomes of the study were estimated through two models, i.e. the conditional logit and random parameter logit models. The heterogeneous willingness to pay amounts for ecosystem services confirm the variations in taste and preferences of the respondents across all sub-basins. Considering spatial heterogeneity of the preferences, the random parameter logit model resulted in smaller transfer errors than the conditional logit model. The values of transfer errors estimated by the random parameter logit model from the lower to the upper sub-basin, from the upper to the middle sub-basin and from the middle to the lower sub-basin were 17.76%, 80.65% and 33.92%, respectively, and the reason for these smaller values is the consideration of taste and preferences of the respondents. On the other hand, the estimated values of transfer errors for the same settings in the conditional logit model were 21.93%, 109.31% and 43.08%, respectively. The transfer error values thus validate the transfer of benefits across all the sub-basins of the river. Therefore, the current findings are helpful in proper management of ecosystem services and permit for benefit transfer from one sub-basin to another sub-basin of Heihe River.

Do driving restriction policies effectively alleviate smog pollution in China?

China has become one of the countries with the most severe smog pollution, especially in winter. Many local governments had to take various measures to combat the smog. The driving restriction is one of the policies being widely implemented throughout the country, but the actual effect has been controversial. Over 30 cities in China adopted the driving restriction policy in winter specifically in recent years. In this study, regression discontinuity (RD) method is applied to 16 cities to study whether the policy was effective or not and to find out the reason behind. It is found that (1) the effect has shown differences in different cities, in Cangzhou, Linfen and Shijiazhuang, the policy was effective on winter smog control, while it was ineffective in Luoyang, Tangshan, Xinyang and Zhoukou. (2) High proportion of secondary industry in GDP and inconvenient public transport system has inhibitory effect on the effectiveness of the driving policy. (3) Population density, GDP, the proportion of urban green area and driving restriction intensity have no significant impact on the effectiveness of the driving restriction policy. (4) In terms of meteorological factors, average temperature, rainfall, wind speed and air pressure have a negative impact on PM2.5, while humidity has a positive impact on PM2.5.

Molecular and morphometric changes in the small intestine during hot and cold exposure in thermally manipulated broiler chickens.

BACKGROUND AND AIM: Thermal stress (hot or cold) is one of many environmental stressors that severely affects the health of broiler chickens. One negative effect of thermal stress is the disruption of the intestinal barrier function in broiler chickens. This study aimed to evaluate the effect of thermal manipulation (TM) on the small intestine in terms of histomorphometry as well as junctional, heat-shock, and immune response gene expression during post-hatch exposure to thermal stress. MATERIALS AND METHODS: The experiment was conducted by dividing 928 fertile Ross eggs into three incubation groups: The control (C) group (incubated at 37.8°C and 56% relative humidity [RH] for the whole incubation period), the TM using low temperature TML group (incubated at 36°C and 56% RH for 18 h/day from embryonic days 7 to 16), and the TM using high temperature (TMH) group (incubated at 39°C and 65% RH for 18 h/day from embryonic days 7 to 16). On post-hatch day 21, 90 chicks were randomly selected from each incubation group and were equally subdivided into three subgroups for the post-hatch thermal stress experiment: The TN subgroup (room temperature maintained at 24°C), the heat stress (HS) subgroup (room temperature maintained at 35°C), and the cold stress (CS) subgroup (room temperature maintained at 16°C). After 1 day of thermal stress exposure (age 22 days), five birds from each subgroup were euthanized and ileum samples were collected to evaluate the transcription of the Claudin (CLDN1), CLDN-5, Occludin, Cadherin-1, heat shock factors (HSF1), HSF3, 70 kilodalton heat shock protein, 90 kilodalton heat shock protein, Interleukin 6 (IL6), IL8, toll-like receptors-2 (TLR2), and TLR4 genes by Real-Time Quantitative Reverse Transcription polymerase chain reaction analysis. Finally, after 4 and 7 days of thermal stress (age 25 and 28 days, respectively), nine chicks were euthanized, and their jejunum and ileum were collected for histomorphometric analysis. RESULTS: After exposure to 1 day of thermal stress, the C subgroups exposed to thermal stress (HS and CS) possessed significantly increased expression of junctional, heat-shock, and immune response genes compared to the C-TN subgroup, and similar results were observed for the TMH. In contrast, thermally stressed TMH subgroups had significantly lower expression of the studied genes compared to C subgroups exposed to thermal stress. Furthermore, no significant changes were detected between the TML subgroups exposed to thermal stress and TML-TN. Moreover, significant alterations in villus height (VH), villus surface area, crypt depth (CD), and VH to CD ratio were observed between the TML, TMH, and C subgroups exposed to CS. CONCLUSION: It might be suggested that TM may have a protective impact on the small intestine histomorphometry and epithelial integrity of broilers during post-hatch exposure to thermal stress.

Expression of digestive enzyme and intestinal transporter genes during chronic heat stress in the thermally manipulated broiler chicken.

Heat stress has a serious impact on nutrient digestion and absorption in broiler chickens. This study aimed to investigate the effects of chronic heat stress (CHS) on the mRNA expression of digestive enzymes and nutrient transporter genes in thermally manipulated (TM) broiler chickens. The evaluated genes encompassed pancreatic lipase, trypsin, amylase, maltase, and alkaline phosphatase as well as certain glucose transporter (GLUT2, SGLT1), amino acid transporter (y+LAT1, CAT1), and fatty acid transporter (FABP1, CD36) genes in the jejunal mucosa. Thermal manipulation was carried out at 39°C and 65% relative humidity for 18 h daily from embryonic days (ED) 10-18, while CHS was induced by raising the temperature to 35°C for 7 D throughout post-hatch days 28 to 35. After 0, 1, 3, 5, and 7 D of CHS, the pancreas and jejunal mucosa were collected from the control and TM groups to evaluate the mRNA expression by relative-quantitative real-time qRT-qPCR. Thermal manipulation significantly decreased the cloacal temperature (Tc) and the hatchling weight, and improved weight gain in broilers during post-hatch life and CHS. In addition, TM decreased the mortality rate during CHS. During CHS, the mRNA expression levels of SGLT1, GLUT2, FABP1, and trypsin were significantly decreased after 1 D in control chickens, and this lower expression persisted until day 7, after which it further decreased. In contrast, in TM chickens, SGLT1, GLUT2, and FABP1 expression decreased after 3, 5, and 7 D of CHS, respectively, while no significant change in trypsin expression was observed throughout the CHS period. Moreover, it was found that TM significantly modulated the mRNA expression dynamics of CD36, alkaline phosphatase, y+LAT1, CAT1, lipase, amylase, and maltase during CHS exposure. The findings of this study suggest that, in broiler chickens, TM has a long-lasting impact on nutrient digestion and absorption capabilities as well as Tc, mortality rates, and BW during CHS.