414 research outputs found

    Simplified Flow and Reactive Transport Modeling to Support Decision-Making about Water Management Strategies

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    In the Indian metropolis of Delhi, the Yamuna River is highly influenced by sewage water, which has led to elevated ammonium (NH4+) concentrations up to 20 mg/L in the river water during 2012–2013. Large drinking water production wells located in the alluvial aquifer draw high shares of bank filtrate. Due to the infiltrating river water, the raw water NH4+ concentrations in some wells exceed the threshold value of 0.5 mg/L ammonia-N of the Indian drinking water specifications, making the water unfit for human consumption without prior treatment. However, to meet the city’s growing water demand, it might be advantageous to consider the long-term use of the well field. This requires the development of an adapted post-treatment unit in concert with an adjusted well field management. To better understand the groundwater dynamics and contamination and decontamination times at the well field, a theoretical modeling study has been conducted. The results of 2D numerical modeling reveal that the groundwater flux beneath the river is negligible because of the aquifer and river geometry, indicating that infiltrating river water is not diluted by the ambient groundwater. Increasing the water abstraction in the wells closest to the river would result in a larger share of bank filtrate and a decreasing groundwater table decline. Simplified 1D reactive transport models set up for a distance of 500 m (transect from the riverbank to the first production well) showed that the NH4+ contamination will prevail for the coming decades. Different lithological units of the aquifer (sand and kankar—a sediment containing calcareous nodules) have a strong influence on the respective contamination and decontamination periods, as the retardation of NH4+ is higher in the kankar than in the sand layer. Although this simplified approach does not allow for a quantification of processes, it can support decision-making about a possible future use of the well field and point to associated research needs

    Anthropogenic and geogenic influences on peri-urban aquifers in semi-arid regions: insights from a case study in northeast Jaipur, Rajasthan, India

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    Rapid urbanization has exerted considerable pressure on groundwater resources in Jaipur, India. Peri-urban areas are particularly affected as the public supply infrastructure often does not reach this fast-growing fringe, which often lacks a planning strategy, leading to an informal water supply based on groundwater. At the same time, the hills and historic reservoirs located in these areas are important for groundwater recharge and, therefore, critical for sustainable groundwater-resource management. To understand the local hydrogeology and the role of anthropogenic influences, a 2-year field study was carried out in northeastern Jaipur. The aim was to develop a conceptual model on which a management concept can be built. The study comprised hydrochemical and stable isotope analyses of water samples, depth-to-water measurements, a leveling survey and geophysical investigations. The study revealed that the groundwater from both the Proterozoic hard rock and the overlying Quaternary alluvial aquifer generally does not meet the Indian drinking water thresholds for nitrate concentration and/or total dissolved solids (TDS). While anthropogenic activities are the main source of quantity problems (declining groundwater levels through overabstraction), the biggest quality problems (nitrate up to 550 mg/L and TDS >500 mg/L) are most likely of geogenic origin and only enhanced by anthropogenic impacts. Quantity and quality aspects improve significantly in areas influenced by recharge from the historic reservoirs, leading to the conclusion that artificial recharge structures may be the way forward to improving community water supply and that groundwater protection should be given priority in these areas

    Forschungswerkstatt FLEx

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    Die Forschungswerkstatt FLEx ist eine interdisziplinäre Einrichtung am Zentrum für Hochschuldbildung und möchte Studierenden Unterstütztung bei ihren Forschungsvorhaben bieten. In dieser Dokumentation wird die Entwicklung der Werkstatt über die ersten drei Semester dargestellt

    Acid-Base Balance in Healthy Adults: Beneficial Effects of Bicarbonate and Sodium-Rich Mineral Water in a Randomized Controlled Trial: The BicarboWater Study

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    Background. Noncommunicable diseases (NCDs) are a global health challenge. The complex etiology of NCDs involves genetic, environmental, and lifestyle factors, including dietary habits. Chronic latent metabolic acidosis has been associated with an increased risk of NCDs. Alkalizing diets and mineral water consumption have shown promise in improving acid-base balance and potentially impacting NCDs. Methods. In this randomized controlled intervention study, the effect of drinking 1,500–2,000 mL of mineral water daily on acid-base balance was evaluated. Ninety-four healthy participants were divided into two groups: one consumed mineral water with a high bicarbonate and sodium content (HBS, n = 49) and the other consumed mineral water with a low bicarbonate and sodium content (LBS, n = 45). Changes in venous blood gas and urinary acid-base parameters were measured over a short-term (3 days) and long-term (28 days) intervention period. Potential renal acid load (PRAL) and nutrient intake were calculated at baseline and after 28 days. Results. HBS water consumption led to increased urinary pH (24-hour urine and spontaneous urine, both p < 0.001) and bicarbonate levels (p < 0.001), accompanied by reduced titratable acids (p < 0.001) and ammonium (p < 0.001), resulting in a lower renal net acid excretion (p < 0.001). These changes occurred in the short term and persisted until the end of the study. LBS consumption showed no significant effects on urinary pH but led to a slight decrease in bicarbonate (p < 0.001) and NH4+ (p < 0.001), resulting in a slight decrease in NAE (p = 0.011). Blood gas changes were modest in both groups. Mineral water consumption in the HBS group altered dietary intake of sodium and chloride, contributing to changes in PRAL values. Conclusion. The study demonstrates that the consumption of mineral water high in bicarbonate and sodium (1,500 mL–2,000 mL/day) can positively influence urinary acid-base parameters and reduce NAE, suggesting potential benefits in maintaining acid-base balance without adverse effects on human health. These findings highlight the importance of mineral water composition in acid-base regulation. This trial is registered with DRKS00025341

    Austrian Students’ Perceptions of Social Distancing and Their Emotional Experiences During Distance Learning Due to the COVID-19 Pandemic

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    The COVID-19 pandemic has led to far-reaching changes in various aspects of students’ lives. In the particular case of the educational field, classroom teaching was drastically shifted to a distance learning format. Consequently, students needed to deal with a completely different everyday school life. Learning was carried out online, which implied that students could not see some of their regular, important social contacts such as teachers, classmates or friends. It is already proven that such social distancing measures had impacts on students’ emotional experiences during the lockdown. Following a mixed-methods concurrent single-phase design, this study examined students’ perceptions of social distancing and their emotional experiences during the first school lockdown in Austria. Data from an online survey (n = 263 students) and from qualitative interviews (n = 56 students) were analyzed. The results show that distance learning drastically reduced interaction among students and between students and their teachers. Furthermore, the results indicate negative emotional experiences due to less social contact, increased learning pressures, and less structure. However, findings revealed that students also experience and perceived positive emotional experiences during distance learning because of more freedom, autonomy, and to some extent, less performance pressure. Based on the findings, the present study discusses possible perspectives on how to support students during and after distance learning, as well as further lines of research.Peer Reviewe

    Observed and personally experienced discrimination: findings of a cross-sectional survey of physicians and nursing staff

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    Background: Discrimination against hospital staff based on ascribed features is prevalent in healthcare systems worldwide. Detrimental effects on health and quality of patient care have been shown. Our study aims to describe and analyse the discrimination experiences of both physicians and nurses, specifically for the German hospital context. Methods: A cross-sectional online survey on observed and personally experienced discrimination at work addressed staff from 22 hospitals of two organizations in Germany. Sociodemographic and occupational as well as institutional characteristics served as independent variables. In multivariable analyses, block- and stepwise logistic regressions were calculated for the two dependent variables (witness and victim of discrimination). Sensitivity analyses with imputed data for missings were performed. Results: N = 800 healthcare professionals (n = 243 physicians, n = 557 nurses; response rate: 5.9%) participated in the survey. 305 respondents (38.1%) were witnesses of discrimination, while 108 respondents (13.5%) were victims of discrimination in their wards. Reasons for observed discriminatory acts were predominantly attributed to the ethnicity of the person concerned, their appearance and language, whereas personally affected staff most frequently cited gender as a reason, followed by ethnicity, and physical appearance. In multivariable models, cultural competence significantly increased the likelihood of witnessing discrimination (beta = .575; p = .037). In terms of the likelihood of being a victim of discrimination, in addition to cultural competence (beta = 2.838; p = < .001), the interaction of the effects of gender and professional group was statistically significant (beta = .280; p = .010). Conclusions: Given the extent of experienced and observed discrimination, appropriate institutional responses are needed. Further research on discriminatory structures in the German-speaking health care system should focus on discrimination at the intersection of ethnicity, gender and occupation
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