June September Research Articles

Winter and spring climate explains a large portion of interannual variability and trend in western U.S. summer fire burned area

This study predicts summer (June–September) fire burned area across the western United States (U.S.) from 1984 to 2020 using ensembles of statistical models trained with pre-fire season climate conditions. Winter and spring climate conditions alone explain up to 53% of the interannual variability and 58% of the increasing trend of observed summer burned area, which suggests that climate conditions in antecedent seasons have been an important driver to broad-scale changes in summer fire activity in the western U.S. over the recent four decades. Relationships between antecedent climate conditions with summer burned area are found to be strongest over non-forested and middle-to-high elevation areas (1100–3300 m). Statistical models that predict summer burned area using both antecedent and fireseason climate conditions have improved performance, explaining 69% of the interannual variability and 83% of the increasing trend of observed burned area. Among the antecedent climate predictors, vapor pressure deficit averaged over winter and spring plays the most critical role in predicting summer fire burned area. Spring snow drought area is found to be an important antecedent predictor for summer burned area over snow-reliant regions in the nonlinear statistical modeling framework used in this analysis. Namely, spring snow drought memory is realized through dry anomalies in land (soil and fuel) and atmospheric moisture during summer, which favours fire activity. This study highlights the important role of snow drought in subseasonal-to-seasonal forecasts of summer burned area over snow-reliant areas.

Admission vital signs as predictors of COVID-19 mortality: a retrospective cross-sectional study

BackgroundCOVID-19 remains a major healthcare concern. Vital signs are routinely measured on admission and may provide an early, cost-effective indicator of outcome – more so in developing countries where such data is scarce. We sought to describe the association between six routinely measured admission vital signs and COVID-19 mortality, and secondarily to derive potential applications for resource-limited settings.MethodsRetrospective analysis of consecutive patients admitted to King Edward VIII Hospital, South Africa, with COVID-19 during June–September 2020 was undertaken. The sample was subdivided into survivors and non-survivors and comparisons made in terms of demographics and admission vital signs. Univariate and multivariate analysis of predictor variables identified associations with in-hospital mortality, with the resulting multivariate regression model evaluated for its predictive ability with receiver operating characteristic (ROC) curve analysis.ResultsThe 236 participants enrolled comprised 153(77.54%) survivors and 53(22.46%) non-survivors. Most participants were Black African(87.71%) and female(59.75%) with a mean age of 53.08(16.96) years. The non-survivor group demonstrated a significantly lower median/mean for admission oxygen saturation (%) [87(78–95) vs. 96(90–98)] and diastolic BP (mmHg) [70.79(14.66) vs. 76.3(12.07)], and higher median for admission respiratory rate (breaths/minute) [24(20–28) vs. 20(20–23)] and glucose (mmol/l) [10.2(6.95–16.25) vs. 7.4(5.5–9.8)]. Age, oxygen saturation, respiratory rate, glucose and diastolic BP were found to be significantly associated with mortality on univariate analysis. A log rank test revealed significantly lower survival rates in patients with an admission oxygen saturation < 90% compared with ≥90% (p = 0.001). Multivariate logistic regression revealed a significant relationship between age and oxygen saturation with in-hospital mortality (OR 1.047; 95% CI 1.016–1.080; p = 0.003 and OR 0.922; 95% CI 0.880–0.965; p = 0.001 respectively). A ROC curve analysis generated an area under the curve (AUC) of 0.778 (p < 0.001) when evaluating the predictive ability of oxygen saturation, respiratory rate, glucose and diastolic BP for in-hospital death. This improved to an AUC of 0.832 (p < 0.001) with the inclusion of age.ConclusionA multivariate regression model comprising admission oxygen saturation, respiratory rate, glucose and diastolic BP (with/without age) demonstrated promising predictive capacity, and may provide a cost-effective means for early prognostication of patients admitted with COVID-19 in resource-limited settings.

Bacterial Isolates and Antibiotic Resistance of Escherichia coli Isolated from Fresh Poultry Excreta Used for Vegetable Farming in Freetown, Sierra Leone.

The transfer of antibiotic resistance from animals to humans is of concern in recent times. One potential source of such transfer is the untreated poultry excreta used as manure in farming. We aim to identify bacterial isolates and antibiotic susceptibility patterns of Escherichia coli in poultry excreta in Sierra Leone. This was a cross-sectional study of fresh poultry excreta samples collected from four commercial poultry sites in Freetown, Sierra Leone, from June–September 2021. Bacterial isolates were tested against eight antibiotics using established standards. Of 100 samples, 93 showed Escherichia coli (93%): of those, eight isolates also had Salmonella (8%). E. coli was 100% resistant to all three ‘Watch’ drugs (erythromycin, cefoxitin and streptomycin) and tetracycline. E. coli was least resistant to ampicillin (12%), followed by chloramphenicol (35%). The prevalence of multidrug resistance was 95.6%. Multiple antibiotic resistance index ranged from 0.5–0.7 (optimal < 0.2), indicating high prior exposure to antibiotics in these poultries. Such high levels of resistance in E. coli isolated from poultry excreta could pose a serious threat to humans. We recommend (i) routine surveillance to monitor antibiotic resistance in poultry excreta, (ii) using poultry excreta as manure only after treatment and (iii) restricting the use of antibiotics as prophylactics and growth promoters in poultry feeds.

Intimate Partner Violence Against Women During the COVID-19 Lockdown in Italy: A Multicenter Survey Involving Anti-Violence Centers.

This study explores intimate partner violence (IPV) evolution during the lockdown with a sample of 238 women (44% cohabitating and 56% not cohabitating with the perpetrator), attending five antiviolence centers in Italy (June–September 2020). Questions included 12 items on IPV and, for each item, a question about whether violence increased/stayed the same/decreased during lockdown; an indicator of IPV modifications was constructed. Two distinct patterns, confirmed after adjustment for socio-demographic factors, emerged: IPV increased for 28% of cohabitating and decreased for 56% of non-cohabitating women. Such results suggest the efficacy of physical distancing—strictly controlled by the State—in the prevention of IPV.

Indirect effects of COVID-19 pandemic on reproductive, maternal, newborn and child health services in Pakistan.

COVID-19 is having many impacts on health, economy and social life; some due to the indirect effects of closure of health facilities to curb the spread. Closures were implemented in Pakistan from March 2020, affecting provision of reproductive, maternal, newborn and child health (RMNCH) services. To appraise the effects of containment and lockdown policies on RMNCH service utilization in order to develop an early response to avoid the catastrophic impact of COVID-19 on RMNCH in Pakistan. Routine monitoring data were analysed for indicators utilization of RMNCH care. The analysis was based on Period 1 (January-May 2020, first wave of COVID-19); Period 2 (June-September 2020, declining number of cases of COVID-19); and Period 3 (October-December 2020, second wave of COVID-19). We also compared data from May and December 2020 with corresponding months in 2019, to ascertain whether changes were due to COVID-19. Reduced utilization was noted for all RMNCH indicators during Periods 1 and 3. There was a greater decline in service utilization during the first wave, and the highest reduction (~82%) was among children aged < 5 years, who were treated for pneumonia. The number of caesarean sections dropped by 57%, followed by institutional deliveries and first postnatal visit (37% each). Service utilization increased from June to September, but the second wave of COVID-19 led to another decrease. To reinstate routine services, priority actions and key areas include continued provision of family planning services along with uninterrupted immunization campaigns and routine maternal and child services.

The puzzle of the anchovy–sardine inverse fishery at the south‐eastern coast of the Arabian Sea and climate variability

AbstractAn out‐of‐phase pattern of fishery between anchovy and sardine exists in upwelling systems of different geographical locations. We examined the inverse relationship of anchovy (Stolephorus sp., Engraulidae) and sardine (Sardinella longiceps, Clupeidae) fishery along the coast of the south‐eastern Arabian Sea (SEAS) by analysing the annual landing data of Kerala, Karnataka, and Goa states. Landings of anchovy and sardine showed wide fluctuations with distinct episodes of abundance and decline. We selected anchovy period (1984–1996) and sardine period (2000–2013) for close examination according to the environmental data availability. The study reveals that the observed inverse fishery along the coast of SEAS is well connected to regional environmental parameters and global climate variability. During the abundant anchovy period, the anomalies of surface currents were observed towards the north and also towards the coast during the spawning periods of anchovy (March–May, October–December). The pattern of surface current anomalies is reversed during the abundant sardine period. Anomalies of surface current is directed towards offshore during the early life stage of sardine (June–September), but it reversed towards the coast during the abundant sardine period. Similarly, an opposite upwelling pattern is noted in both species’ spawning seasons during the anchovy and sardine abundant periods. During these periods, the spatial distribution of global surface air temperature and wind anomalies showed contrasting spatial patterns and hence they are related to various climate indices in sardine and anchovy abundant periods in the SEAS.

Reducing Anxiety with Nature and Gardening (RANG): Evaluating the Impacts of Gardening and Outdoor Activities on Anxiety among U.S. Adults during the COVID-19 Pandemic.

The COVID-19 pandemic impacted mental health. Growing research has identified the mental health benefits of nature contact, including gardening. We used a cross-sectional survey to investigate the association between gardening and other outdoor activities with anxiety among U.S. adults. The RANG (Reducing Anxiety with Nature and Gardening) survey was distributed online from June–September 2020 through social media (Twitter and Facebook) and a national Master Gardeners listserv. Survey questions captured demographics, COVID-19 experiences, gardening, outdoor activities, and anxiety using the Generalized Anxiety Disorder 7-item scale. Data were analyzed using chi-square, Fisher’s exact, and Kruskal–Wallis tests, as well as logistic regression. Among participants, 46% reported anxiety symptoms. Participants who had gardened ≥ 15 years and those gardening > 8 h over two weeks had lower anxiety scores. Spending more time outdoors on weekdays also decreased anxiety scores. After adjusting for covariates, lower odds of anxiety were identified for 50–69 and 70–89-year-olds vs. 18–29-year-olds; males vs. females; and Texas vs. Maryland residents. These findings confirm increased anxiety during the COVID-19 pandemic and suggest that sustained gardening and other outdoor activities could help reduce anxiety.

River Health Assessment Method Based on Water Quality Indices for the Dagujia River in China

River health has become one of the major concerns today. This study develops a water quality index-based health assessment method to diagnose the status of the Dagujia River, China. The Dagujia River is the second largest river and the main source of drinking water in Yantai, China. The health status is classified into five levels – ideal, healthy, sub-healthy, unhealthy, and morbid. The assessment process includes four phases: 1) index layer grading, 2) criterion layer grading, 3) target layer grading, and 4) health diagnosis. The results show that eight sections are morbid, accounting for 66.3% of the entire assessed river. It also finds that higher water temperature variation (WTV) results in this poor health situation. However, the assessment excluding WTV reveals that all the other sections are in ideal states except for a sub-healthy river section caused by the higher concentrations of CODMn and COD in the high-flood season (June–September).

How Do Different Types of University Academics Perceive Work from Home Amidst COVID-19 and Beyond?

The COVID-19 pandemic resulted in a massive and unintentional shift to work from home (WFH) or working remotely, as well as broad adoption of web-based platforms. The goal of this research is to uncover the attitudes to WFH among different types of academics in the Sri Lankan higher education sector. An online questionnaire survey was conducted amidst a severe COVID-19 wave during June–September 2021, and 337 valid responses were received. The questionnaire contained 49 questions under four sections excluding demographic questions. The gathered data were analysed using multiple regression models. Results of the study ascertained a significant (p &lt; 0.01) positive attitude among academics towards online teaching (academic orientation), other than academics who from disciplines with more practical components, and there was a significant (p &lt; 0.01) positive attitude among academics to conducting research (research orientation) while WFH. Further, the findings indicate a significant (p &lt; 0.01) negative attitude to WFH when disseminating knowledge and engaging in community services with various stakeholders. When considering the criticality of demographics variables in the new normal, a hybrid working model can be introduced by reaping the benefits of WFH based on different types of academic orientations and their favourability towards the WFH model, rather than reverting to a full physical academic working environment. As a developing country, Sri Lanka can formulate policies on effective hybrid working models for academics to realise the potential from the lessons learned. This experience will enable the country to accomplish or move towards accomplishing the fourth goal of SDGs, quality education by 2030.

Returning a Shelter Dog: The Role of Owner Expectations and Dog Behavior

Simple SummaryMost dog adopters are typically highly satisfied with dog ownership, although a number of adopted dogs are returned to animal shelters following adoption, which can be stressful for the owner and the dog. In this study, we looked at adopters’ expectations for dog ownership prior to adoption and their experience with dog behavior in the first days, weeks, and months following adoption relative to the risk of return. We found owners who returned their dog to the shelter within three months of adoption had higher expectations for their dog to be healthy, exhibit desirable behavior, and for the human–dog bond compared with adopters who did not return their dogs. There were no differences in expectations for ownership responsibilities and challenges between returning and non-returning owners. We also found two-thirds of owners experienced some behavioral problems following adoption, although behaviors such as training difficulty and fear decreased over time. Our findings may be useful for animal shelters to reduce returns by ensuring adopters have realistic expectations about the human–dog relationship and the occurrence of behavioral problems.Millions of animals are adopted from animal shelters in the United States each year, although some are returned post-adoption, which can decrease both the animals’ chances of future adoptions and the owners’ willingness to adopt again. In this study, we investigated the impact of adopter expectations for ownership and animal behavioral problems on post-adoptive dog returns at a large animal shelter in South Carolina. Between June–September 2021, 132 dog adopters completed a survey about their expectations for ownership through Qualtrics. Twenty-nine adopters returned their dogs to the shelter within three months of adoption, with a median length of ownership of eight days. Owners completed follow-up questionnaires about their perceptions of adoption and dog behavior at two days, two weeks, and four months post-adoption. Categorical principal component analysis revealed three factors pertaining to adopters’ expectations for ownership. Independent t-tests showed returning owners had significantly higher expectations for dog behavior and health (t = −2.32, p = 0.02) and the human–dog bond compared with non-returning owners (t = −2.36, p = 0.02). Expectations for ownership responsibilities did not differ between the groups. Two-thirds of adopters experienced dog behavioral problems post-adoption, although training difficulty decreased significantly between two days and four months (F = 5.22, p = 0.01) and nonsocial fear decreased between two weeks and four months post-adoption (X2 = 10.17, p = 0.01). Shelters may benefit from utilizing adoption counselling to ensure adopters understand the potential for dog behavioral problems in the early stages of ownership and develop appropriate expectations for the human–dog relationship. Post-adoption behavioral support may also help some owners to overcome behavioral difficulties as their dogs adapt to the new environment.

Photosynthesis, Yield and Quality of Soybean (Glycine max (L.) Merr.) under Different Soil-Tillage Systems

Due to current climate changes and drought periods, it is recommended to cultivate soybean in no-plowing tillage systems. The conducted research is to contribute to a partial explanation of the course of photosynthesis processes in soybean plants, which may facilitate the decision making before sowing this species in a given tillage system. The aim of the study was to assess the dependence of photosynthesis on the yield and variable hydrothermal conditions of tillage systems, as well as their impact on the productivity and quality of soybean. A field experiment was carried out using soybean cv. Merlin, between 2017 and 2019 in Boguchwała, Poland. The plant tested was soybean cv. Merlin. The tillage systems—conventional (CT), reduced (RT) and no-tillage (NT)—were the experimental factors. The use of CT and RT influenced growth in leaf area index (LAI) and soil plant analysis development (SPAD) and improved the photosynthesis process, which increased the values of the maximal quantum yield of the photolysis system of the donor side of PSII (Fv/F0), and performance index of PS II (PI) and net photosynthetic rate (PN), stomatal conductance (gs) parameters, compared to NT. CT treatment increased the yield of soybean plants to significantly higher compared with NT treatment, and seeds treated with the CT treatment contained more protein. The content of fat and phosphorus (P) were significantly higher in the NT system and the content of potassium (K) from RT. In 2017, under drought conditions (the June–September period), the seed yield of NT was similar to the yield of CT and significantly higher than the yield of RT. The higher value of hydrothermal coefficients in 2019 resulted in an increase in photosynthesis parameters, seed yield as well as the content of fat and elements P and K.

Modulation of the Intraseasonal Chlorophyll‐a Concentration in the Tropical Indian Ocean by the Central Indian Ocean Mode

AbstractThis study diagnoses the drivers of intraseasonal variability of mixed layer chlorophyll‐a (Chl) concentration in the tropical Indian Ocean during boreal summer (June–September) using a well‐tested coupled ocean‐ecosystem model. Results show that wind forcing is the primary source for energetic intraseasonal Chl concentration variability in the eastern Arabian Sea and western Bay of Bengal (BoB) modulated by the Central Indian Ocean (CIO) mode. The atmospheric anomalous anticyclone associated with the positive phase of CIO mode drives southeastward currents in the Arabian Sea, which transport nutrient and Chl towards the east. Simultaneously, the wind‐induced offshore currents strengthen upwelling in the western boundary of BoB, resulting in enhanced Chl in the upper ocean. Conversely, because of the formation of a barrier layer, the nutrient supply is suppressed along the equator, which causes a negative correlation between the CIO mode and Chl. This study complements the Madden‐Julian Oscillation forcing on the intraseasonal Chl concentration anomaly in the tropical Indian Ocean.

Evaluation of WRF Cumulus Parameterization Schemes for the Hot Climate of Sudan Emphasizing Crop Growing Seasons

High spatiotemporal resolution climate data are essential for climate-related impact studies. The Weather Research and Forecasting (WRF) model is widely used to downscale climate data for different regions with regional-specific physics configurations. This study aimed to identify robust configurations of the WRF model, especially cumulus parameterization schemes, for different climatic zones of Sudan. We focused on wet season (June–September) rainfall and dry season (November–February) temperature, which are determinants of summer crop and irrigated wheat yields, respectively. Downscaling experiments were carried out to compare the following schemes: Betts–Miller–Janjic (BMJ), improved Kain–Fritch (KFT), modified Tiedtke (TDK), and Grell–Freitas (GF). Results revealed that the BMJ performed better for wet season rainfall in the hyper-arid and arid zones; KFT performed better for rainfall in July and August in the semi-arid zone where most summer crops are cultivated. For dry season temperature, the BMJ and TDK outperformed the other schemes in all three zones, except that the GF performed best for the minimum temperature in December and January in the arid zone, where irrigated wheat is produced, and in the semi-arid zone. Specific parameterization schemes therefore need to be selected for specific seasons and climatic zones of Sudan.

Long-lasting effects of experimental flow intermittency on alpine stream macroinvertebrates (Val Roseg, Switzerland)

Changing weather patterns and receding glaciers are predicted to increase flow intermittency in alpine streams. If aquatic macroinvertebrate communities largely comprise taxa adapted to perennial flows, an increase in flow intermittency substantially reduces biodiversity and affects functional processes. We conducted a before-after-control-impact field experiment to examine how macroinvertebrate communities in an alpine headwater stream responded to and recovered from a repeated experimental increase in flow intermittency. Flow in one channel was manipulated to simulate increased summer intermittency (June–September) over two consecutive years, whilst an adjacent channel served as a control. We monitored the density of benthic macroinvertebrates, periphyton and organic matter at approximately monthly intervals over three years during the snow-free period. Before manipulation, both channels had similar ecological properties. The flow manipulation reduced the overall macroinvertebrate density, and especially the proportional rheophile density, across both years. Recovery of the macroinvertebrate community following experimental flow intermittency took more than a year, and longer than our study period. This could be due to long aquatic life stages, dispersal limitation and biotic interactions. We conclude that climate-induced changes in alpine stream flow regimes can lead to a fundamental shift in macroinvertebrate assemblages through local extinctions, mostly of rheophilic species.

Effectiveness of Emamectin Benzoate and Propiconazole for Protecting Picea engelmannii (Pinales: Pinaceae) from Mortality Attributed to Dendroctonus rufipennis (Coleoptera: Curculionidae) in Wyoming

Spruce beetle, Dendroctonus rufipennis Kirby (Coleoptera: Curculionidae), causes significant mortality of mature spruce, Picea spp. (Pinales: Pinaceae), in western North America. We evaluated the effectiveness of two formulations of bole injections of emamectin benzoate (TREE-äge® G4 and TREE-äge R10; Arborjet, Inc., Woburn, MA) alone and combined with propiconazole (Propizol®; Arborjet, Inc.) for protecting Engelmann spruce, Picea engelmannii Parry ex Engelm., from mortality attributed to colonization by D. rufipennis. Treatments were injected 16–19 July 2017, and levels of Pi. engelmannii mortality were determined for 2018 and 2019. Each experimental tree (n = 30, including an untreated control group) was baited with aggregation pheromone (frontalin) June–September 2018. All surviving treated Pi. engelmannii and a second untreated control group were baited June–September 2019. Both TREE-äge G4 and TREE-äge R10 significantly reduced levels of Pi. engelmannii mortality compared with the untreated control; however, protection was limited to one field season. Protection was increased to two field seasons by combining TREE-äge G4 and TREE-äge R10 with Propizol. The addition of Propizol, a triazole fungicide, likely reduced the progression of blue stain within treated Pi. engelmannii increasing tree health and resistance to D. rufipennis.

The Seroprevalence of SARS-CoV-2 Antibodies among HealthCare Workers in University Hospital in Krakow before the Era of Vaccination.

Background: Knowledge of occupational health is crucial to the safety of healthcare workers in the pandemic period. The aim of our study was the rating of SARS-CoV-2 seroprevalence in connection with selected demographic, social, and organizational factors, as well as the identification of key elements determining the safety of HCWs and patients of the University Hospital in Krakow. Methods: This was a non-interventional, uncontrolled, open, single-center, cross-sectional online survey on the preparedness for the COVID-19 epidemic and the seroprevalence of medical and non-medical HCWs and students. Serum specimens from 1221 persons were tested using an immunoassay analyzer based on the ECLIA technique for the anti-SARS-CoV-2 antibodies IgM + IgG. Results: The total seroprevalence was 42.7%. In medical students it was 25.2%, while in physicians it was 43.4% and in nurses/midwives it was 48.1%. Of those who tested positive, 21.5% did not know their serological status. The use of personal protective equipment did not have any significant impact on the result of testing for anti-SARS-CoV-2 antibodies. The risk of developing the disease was not influenced by sex, professional work experience, workplace, or intensity of contact with the patient. Among the studied elements, only care of COVID-19 patients significantly increased the risk. The protective factor was starting work between the waves of the epidemic (June–September 2020). Conclusions: PPE is only one element of infection prevention and control—without other components, such as hand hygiene, it can be dangerous and contribute to self-infection. It is also very important to test healthcare workers. Not being aware of the COVID-19 status of HCWs poses a threat to other staff members, as well as patients and the family and friends of the infected. Thus, extreme caution should be applied when employing respirators with exhalation valves during the COVID-19 pandemic.

Estimating groundwater use and demand in arid Kenya through assimilation of satellite data and in-situ sensors with machine learning toward drought early action

Groundwater is an important source of water for people, livestock, and agriculture during drought in the Horn of Africa. In this work, areas of high groundwater use and demand in drought-prone Kenya were identified and forecasted prior to the dry season. Estimates of groundwater use were extended from a sentinel network of 69 in-situ sensored mechanical boreholes to the region with satellite data and a machine learning model. The sensors contributed 756 site-month observations from June 2017 to September 2021 for model building and validation at a density of approximately one sensor per 3700 km2. An ensemble of 19 parameterized algorithms was informed by features including satellite-derived precipitation, surface water availability, vegetation indices, hydrologic land surface modeling, and site characteristics to dichotomize high groundwater pump utilization. Three operational definitions of high demand on groundwater infrastructure were considered: 1) mechanical runtime of pumps greater than a quarter of a day (6+ hr) and daily per capita volume extractions indicative of 2) domestic water needs (35+ L), and 3) intermediate needs including livestock (75+ L). Gridded interpolation of localized groundwater use and demand was provided from 2017 to 2020 and forecasted for the 2021 dry season, June–September 2021. Cross-validated skill for contemporary estimates of daily pump runtime and daily volume extraction to meet domestic and intermediate water needs was 68%, 69%, and 75%, respectively. Forecasts were externally validated with an accuracy of at least 56%, 70%, or 72% for each groundwater use definition. The groundwater maps are accessible to stakeholders including the Kenya National Drought Management Authority (NDMA) and the Famine Early Warning Systems Network (FEWS NET). These maps represent the first operational spatially-explicit sub-seasonal to seasonal (S2S) estimates of groundwater use and demand in the literature. Knowledge of historical and forecasted groundwater use is anticipated to improve decision-making and resource allocation for a range of early warning early action applications.

Transmission of SARS-CoV-2 in the Population Living in High- and Low-Density Gradient Areas in Dhaka, Bangladesh.

Community transmission of SARS-CoV-2 in densely populated countries has been a topic of concern from the beginning of the pandemic. Evidence of community transmission of SARS-CoV-2 according to population density gradient and socio-economic status (SES) is limited. In June–September 2020, we conducted a descriptive longitudinal study to determine the community transmission of SARS-CoV-2 in high- and low-density areas in Dhaka city. The Secondary Attack Rate (SAR) was 10% in high-density areas compared to 20% in low-density areas. People with high SES had a significantly higher level of SARS-CoV-2-specific Immunoglobulin G (IgG) antibodies on study days 1 (p = 0.01) and 28 (p = 0.03) compared to those with low SES in high-density areas. In contrast, the levels of seropositivity of SARS-CoV-2-specific Immunoglobulin M (IgM) were comparable (p > 0.05) in people with high and low SES on both study days 1 and 28 in both high- and low-density areas. Due to the similar household size, no differences in the seropositivity rates depending on the population gradient were observed. However, people with high SES showed higher seroconversion rates compared to people with low SES. As no difference was observed based on population density, the SES might play a role in SARS-CoV-2 transmission, an issue that calls for further in-depth studies to better understand the community transmission of SARS-CoV-2.

Moisture history in the Northeast China since 1750s reconstructed from tree-ring cellulose oxygen isotope

Northeast China has suffered many serious droughts, with loss of agricultural production. A lack of long-term monitoring data has hindered our understanding of drought characteristics and mechanisms. The moisture-related history of the region was investigated by constructing a tree-ring cellulose δ18O chronology for the period 1752–2015 using samples collected from four Korean pine (Pinus koraiensis) trees in eastern NE China. Results indicate that tree-ring δ18O values are significantly correlated with summer (June–September) precipitation, relative humidity, and drought severity. The tree-ring δ18O chronology accounts for 50.7% of the observed variance in summer relative humidity and was used to reconstruct regional relative humidity levels back to 1752. Compared with previous reconstructions of drought-related changes in NE China, the reconstruction reveals more high- and low-frequency variability, with two drought periods during the 1750s–1820s and 1960s–2015, and a wet period during 1820–1960. Regional drying trends is mainly influenced by a weakened East Asia summer monsoon (EASM), with both drought periods being concurrent with high temperatures and a weak EASM. Together with the global warming trend, the increasing temperature and associated precipitation reduction in NE China indicates increasing likelihood of drought for the region in future.

Monitoring of The Safety and Quality of Water of La Ferme Impounding Reservoir of Mauritius

Water supply from La Ferme impounding reservoir is primarily intended for agricultural use. Unfortunately, there is a concern that the reservoir water is potentially befouled by agrochemicals and pollutants from nearby farms, feeder canals and a solid waste transfer station. The nutrient influx into La Ferme could favour the growth of toxin-producing cyanobacteria which could eventually jeopardize human and animal health. This research is aimed at assessing the water quality of La Ferme reservoir. Water was sampled at the intake tower and two rivers that discharge into La Ferme during summer/rainy (November–April) and winter/dry (June–September) seasons. The mean cyanobacterial count and level of orthophosphate, nitrate and total organic carbon in the reservoir were 63,738 cells/mL, 0.065 mg/L, 0.125 mg/L and 4.8 ppm, respectively. Orthophosphate and total organic carbon levels were significantly positively correlated with cyanobacterial cell counts. The mean orthophosphate level in reservoir water was found to be significantly higher (p ≤ 0.05) during rainy seasons (0.08 mg/L) compared to dry seasons (0.04 mg/L). Residues of herbicide tebuthiuron and cyanotoxin microcystin-LR were also detected with a mean concentration of 0.15 and 0.3 mg/L, respectively. This study highlights the potential eutrophic status of La Ferme reservoir and contamination of its watersheds by microalgal toxin and herbicide that could compromise the ecological integrity of the reservoir and negatively impact the sustainable use of this natural resource.