30 research outputs found

    Crisis y apocalipsis. Notas para un anĂĄlisis de la reflexiĂłn scholemiana sobre el mesianismo

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    This paper aims to explore the reading of Jewish messianism provided by the great historian of Jewish mysticism Gershom Scholem (1897-1982). Starting by showing how messianism has been at the center of Scholem’s attention since the beginning of his scholarly activity, the main motives at the core of Scholem’s description of the messianic phenomenon are investigated. The article points out Scholem’s opposition to a positivist and neo-kantian conception of history, his predilection for the apocalyptical interpretation of Jewish messianism, and his fascination for radical movements such as Sabbatianism and Frankism. In the final part an explanation of the main critiques moved against Scholem’s view of messianism by Jacob Taubes (1923-1987) is also offered.En este artĂ­culo se propone explorar la lectura del mesianismo judĂ­o ofrecida por el gran historiador de la Qabbalah Gershom Scholem (1897-1982). En primer lugar se muestra cĂłmo el mesianismo ha marcado profundamente la investigaciĂłn de Scholem desde el principio de su actividad acadĂ©mica. Posteriormente se busca esclarecer las lĂ­neas principales en la descripciĂłn scholemiana del fenĂłmeno mesiĂĄnico: su oposiciĂłn a la concepciĂłn positivista y neokantiana de la historia, su predilecciĂłn por una interpretaciĂłn apocalĂ­ptica del mesianismo judĂ­o y su fascinaciĂłn por movimientos radicales como el sabatianismo y el frankismo. Finalmente se ofrece un anĂĄlisis de las crĂ­ticas de Jacob Taubes (1923-1987) a la visiĂłn scholemiana del mesianismo

    Filosofia dell’incertezza. Su un appunto del giovane Kafka

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    The paper analyses one of Kafka’s earliest texts by contextualising its philosophical discourse in connection with the teaching of philosophy in contemporary Prague. It starts by referring to Brentano’s supposedly influence on Kafka and it moves on by discussing Max Brod’s tumultuous relation with the Prague Brentanist circle. Kafka’s and Brod’s participation to the Café Louvre philosophical meetings and to the Fanta Salon is also taken into consideration. Finally, the contribution tries to relate Kafka’s fragment to one of its earliest stories: Description of a Struggle (Beschreibung eines Kampfes).Keywords: Franz Kafka; Franz Brentano; Max Brod; Fanta Circle; Anton Mart

    Maintenance sunitinib or observation in metastatic pancreatic adenocarcinoma: a phase II randomised trial

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    Background: New strategies to prolong disease control warrant investigation in patients with metastatic pancreatic adenocarcinoma. This open-label, randomised, multi-centre phase II trial explored the role of maintenance sunitinib after first-line chemotherapy in this setting. Methods: Patients with pathologic diagnosis of metastatic pancreatic adenocarcinoma, performance status >50%, no progression after 6 months of chemotherapy were centrally randomised by an independent contract research organisation, which was also responsible for data collection and monitoring, to observation (arm A) or sunitinib at 37.5mg daily until progression or a maximum of 6 months (arm B). The primary outcome measure was the probability of being progression-free at 6 months (PFS-6) from randomisation. Assuming P0 = 10%; P1 = 30%, α .10; ÎČ .10, the target accrual was 26 patients per arm. Results: 28 per arm were randomised. One arm B patient had kidney cancer and was excluded. Sunitinib was given for a median of 91 days (7-186). Main grade 3-4 toxicity was thrombocytopenia, neutropenia and hand-foot syndrome (12%), diarrhoea 8%. In arm A versus B, PFS-6 was 3.6% (95% confidence interval (CI): 0-10.6%) and 22.2% (95% CI: 6.2-38.2%; P<0.01); 2 y overall survival was 7.1% (95% CI: 0-16.8%) and 22.9% (95% CI: 5.8-40.0%; P = 0.11), stable disease 21.4% and 51.9% (P = 0.02). Conclusion: This is the first randomised trial on maintenance therapy in metastatic pancreatic adenocarcinoma. The primary end-point was fulfilled and 2 y overall survival was remarkably high, suggesting that maintenance sunitinib is promising and should be further explored in this patient population

    Contested Heritage

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    In the wake of the Nazi regime’s policies, European Jewish cultural property was dispersed, dislocated, and destroyed. Books, manuscripts, and artworks were either taken by their fleeing owners and were transferred to different places worldwide, or they fell prey to systematic looting and destruction under German occupation. Until today, a significant amount of items can be found in private and public collections in Germany as well as abroad with an unclear or disputed provenance. Contested Heritage. Jewish Cultural Property after 1945 illuminates the political and cultural implications of Jewish cultural property looted and displaced during the Holocaust. The volume includes seventeen essays, accompanied by newly discovered archival material and illustrations, which address a wide range of topics: from the shifting meaning and character of the objects themselves, the so-called object biographies, their restitution processes after 1945, conflicting ideas about their appropriate location, political interests in their preservation, actors and networks involved in salvage operations, to questions of intellectual and cultural transfer processes revolving around the moving objects and their literary resonances. Thus, it offers a fascinating insight into lesser-known dimensions of the aftermath of the Holocaust and the history of Jews in postwar Europe

    Contested Heritage

    Get PDF
    In the wake of the Nazi regime’s policies, European Jewish cultural property was dispersed, dislocated, and destroyed. Books, manuscripts, and artworks were either taken by their fleeing owners and were transferred to different places worldwide, or they fell prey to systematic looting and destruction under German occupation. Until today, a significant amount of items can be found in private and public collections in Germany as well as abroad with an unclear or disputed provenance. Contested Heritage. Jewish Cultural Property after 1945 illuminates the political and cultural implications of Jewish cultural property looted and displaced during the Holocaust. The volume includes seventeen essays, accompanied by newly discovered archival material and illustrations, which address a wide range of topics: from the shifting meaning and character of the objects themselves, the so-called object biographies, their restitution processes after 1945, conflicting ideas about their appropriate location, political interests in their preservation, actors and networks involved in salvage operations, to questions of intellectual and cultural transfer processes revolving around the moving objects and their literary resonances. Thus, it offers a fascinating insight into lesser-known dimensions of the aftermath of the Holocaust and the history of Jews in postwar Europe

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Geochemical Investigation of Arsenic in Drinking Water Sources in Proximity of Gold Mining Areas within the Lake Victoria Basin, in Northern Tanzania

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    Access to safe drinking water is a challenge for rural communities in many developing countries. Drinking contaminated water endangers human health and impairs social and economic development. Arsenic (As) is a metalloid widely distributed into the environment and is highly toxic in its trivalent inorganic form. The natural occurrence of As in groundwater used for drinking has been associated to the insurgence of skin disorders and respiratory diseases in many parts of the world. Arsenic is frequently found in the form of sulphide in gold deposits. Human exposure to As via drinking water has resulted from gold mining activities in some instances in USA, Asia, South America and Africa. The problem of As in drinking water has been brought to attention in Tanzania only few years ago and further investigation are therefore needed to enable an early detection of harmful exposures. This study aims to assess occurrence, source and mobilization mechanisms of As in some drinking water sources within the Lake Victoria Basin, in Northern Tanzania. Rural communities living in areas known for artisanal and large-scale gold mining activities were the target of the present study. Fifty-four water samples were collected from a variety of drinking water sources (spring, borehole, river and shallow well) in Mara and Geita region during October 2016. pH, electrical conductivity (EC), Redox potential (Eh) and As were measured in situ. Major ions, dissolved organic carbon (DOC) and trace elements, including As, were analysed in the sampled water at KTH-Royal Institute of Technology, in Sweden. 53% of the sampled water do not comply with the WHO recommended limit of 10 ÎŒg/L, representing a serious health risk for some rural communities within the Lake Victoria Basin. The spatial distribution of As in the area under investigation is highly heterogeneous and it is mainly influenced by local geology and proximity to the mining sites (approx. < 5 km). Lower As levels in boreholes than in rivers and shallow wells indicates contamination of surface drainage by mining activities and suggest that deep groundwater ( > 40 m) generally represent a source of safer drinking water. The field-measured Redox potential indicates oxidising conditions, suggesting that oxidation-dissolution of arsenic sulphide minerals is a major mechanism of arsenic mobilization in groundwater. However, this study reveals that several geochemical processes control fate and mobility of As, once it has been released into the aquatic environment. Large discrepancies between field and laboratory measurements of As indicates a strong partition of the metalloid into the particulate fraction. As revealed by the geochemical modelling, co-precipitation with iron /aluminium hydroxides and adsorption on clay minerals are presumed to be the major sinks for dissolved As. Moreover, a good match between peaks in As and dissolved organic carbon concentrations suggests that complexation by humic acids is responsible for enhanced As mobility. Overall, the present study has led to a better understanding of the problem of arsenic in proximity of gold mining areas in Tanzania and it calls for the development of affordable and sustainable solutions which would provide safe drinking water to the affected population.TillgĂ„ngen till rent, sĂ€kert vatten Ă€r en utmaning pĂ„ landsbygdssamhĂ€llen i mĂ„nga utvecklingslĂ€nder. ÅtgĂ„ng pĂ„ förorenat vatten riskerar mĂ€nniskors hĂ€lsa och skadar social och ekonomisk utveckling. Naturlig förekomst av arsenik (As) i grundvatten Ă€r ett globalt miljöproblem, vilket utgör en allvarlig risk för mĂ€nniskors hĂ€lsa pĂ„ grund av metalloidens höga toxicitet. Med tanke pĂ„ att arsenic sulfids mineraler Ă€r en viktigt del av guld insĂ€ttning, har guldgruva aktiviteter anvisas som en orsak till att föroreningar av drĂ€nering och grundvatten i flera lĂ€nder. Problemet med As i dricksvatten har uppmĂ€rksammats i Tanzania för nĂ„gra Ă„r sedan och det krĂ€vs ytterligare undersökning för att möjliggöra tidig upptĂ€ckt av skadliga exponeringar. Denna studie syftar till att bedöma förekomsten, kĂ€llan och mobiliseringsmekanismerna för arsenik i vissa dricksvattenkĂ€llor i Lake Victoria Basin, i norra Tanzania. LandsbygdssamhĂ€llen som Ă€r kĂ€nda för hantverksmĂ€ssiga och storskaliga guldgruva arbeten var mĂ„let för den nuvarande studien. Femtiofyra vattenprover samlades frĂ„n kĂ€llvatten, borehĂ„lsvatten, floder och grundbrunn i Mara och Geita-regionen under oktober 2016. pH, redoxpotential (Eh), temperatur och elektrisk konduktivitet (EC) mĂ€ttes i fĂ€lt. Vattenprovernas koncentration av an- och katjoner, spĂ„rĂ€mnen (bl.a. arsenik), As(III) samt löst organiskt kol (DOC) analyserades i Sverige pĂ„ Kungliga Tekniska Högskolan (KTH). Femtiotre procent av det provtagna vattnet överensstĂ€mmer inte med WHO:s rekommenderade grĂ€ns pĂ„ 10 ÎŒg / l, vilket utgör en allvarlig hĂ€lsorisk fö vissa landsbygdssamhĂ€len i Victoria-sjö. Den geografiska fördelningen av As i det undersökta omrĂ„det Ă€r högst heterogen och pĂ„verkas huvudsakligen av lokal geologi och nĂ€rhet till gruvplatserna (ca <5km). LĂ€gre As-nivĂ„r i borehĂ„l Ă€n i floder och grunda brunnar visar att föroreningar av drĂ€nering pĂ„grund av gruvverksamhet och föeslĂ„r att djupt grundvatten (> 40m) i allmĂ€het utgör en kĂ€lla till sĂ€krare dricksvatten. DĂ€remot, visar denna studie att flera geokemiska processer kontrollerar förutbestĂ€mmelse och röligheten för As, nĂ€ det har blivit frislĂ€ppts ut i vattenmiljö. Stora skillnader mellan fĂ€lt- och labbmĂ€ningar av As indikerar en stark partition av metalloid i partikelfraktionen. Som avslöjas av geokemisk modellering antas, samutfĂ€llning med jĂ€rn / aluminiumhydroxider och adsorption pĂ„ lermineraler vara de huvudsakliga sĂ€nkorna fö upplöst As. Dessutom antyder en bra matchning mellan toppar i As och upplösta organiska kolkoncentrationer att komplexbildning med humana och fulviska syror Ă€r ansvarig för föbĂ€ttrad rölighet

    Geochemical Investigation of Arsenic in Drinking Water Sources in Proximity of Gold Mining Areas within the Lake Victoria Basin, in Northern Tanzania

    No full text
    Access to safe drinking water is a challenge for rural communities in many developing countries. Drinking contaminated water endangers human health and impairs social and economic development. Arsenic (As) is a metalloid widely distributed into the environment and is highly toxic in its trivalent inorganic form. The natural occurrence of As in groundwater used for drinking has been associated to the insurgence of skin disorders and respiratory diseases in many parts of the world. Arsenic is frequently found in the form of sulphide in gold deposits. Human exposure to As via drinking water has resulted from gold mining activities in some instances in USA, Asia, South America and Africa. The problem of As in drinking water has been brought to attention in Tanzania only few years ago and further investigation are therefore needed to enable an early detection of harmful exposures. This study aims to assess occurrence, source and mobilization mechanisms of As in some drinking water sources within the Lake Victoria Basin, in Northern Tanzania. Rural communities living in areas known for artisanal and large-scale gold mining activities were the target of the present study. Fifty-four water samples were collected from a variety of drinking water sources (spring, borehole, river and shallow well) in Mara and Geita region during October 2016. pH, electrical conductivity (EC), Redox potential (Eh) and As were measured in situ. Major ions, dissolved organic carbon (DOC) and trace elements, including As, were analysed in the sampled water at KTH-Royal Institute of Technology, in Sweden. 53% of the sampled water do not comply with the WHO recommended limit of 10 ÎŒg/L, representing a serious health risk for some rural communities within the Lake Victoria Basin. The spatial distribution of As in the area under investigation is highly heterogeneous and it is mainly influenced by local geology and proximity to the mining sites (approx. < 5 km). Lower As levels in boreholes than in rivers and shallow wells indicates contamination of surface drainage by mining activities and suggest that deep groundwater ( > 40 m) generally represent a source of safer drinking water. The field-measured Redox potential indicates oxidising conditions, suggesting that oxidation-dissolution of arsenic sulphide minerals is a major mechanism of arsenic mobilization in groundwater. However, this study reveals that several geochemical processes control fate and mobility of As, once it has been released into the aquatic environment. Large discrepancies between field and laboratory measurements of As indicates a strong partition of the metalloid into the particulate fraction. As revealed by the geochemical modelling, co-precipitation with iron /aluminium hydroxides and adsorption on clay minerals are presumed to be the major sinks for dissolved As. Moreover, a good match between peaks in As and dissolved organic carbon concentrations suggests that complexation by humic acids is responsible for enhanced As mobility. Overall, the present study has led to a better understanding of the problem of arsenic in proximity of gold mining areas in Tanzania and it calls for the development of affordable and sustainable solutions which would provide safe drinking water to the affected population.TillgĂ„ngen till rent, sĂ€kert vatten Ă€r en utmaning pĂ„ landsbygdssamhĂ€llen i mĂ„nga utvecklingslĂ€nder. ÅtgĂ„ng pĂ„ förorenat vatten riskerar mĂ€nniskors hĂ€lsa och skadar social och ekonomisk utveckling. Naturlig förekomst av arsenik (As) i grundvatten Ă€r ett globalt miljöproblem, vilket utgör en allvarlig risk för mĂ€nniskors hĂ€lsa pĂ„ grund av metalloidens höga toxicitet. Med tanke pĂ„ att arsenic sulfids mineraler Ă€r en viktigt del av guld insĂ€ttning, har guldgruva aktiviteter anvisas som en orsak till att föroreningar av drĂ€nering och grundvatten i flera lĂ€nder. Problemet med As i dricksvatten har uppmĂ€rksammats i Tanzania för nĂ„gra Ă„r sedan och det krĂ€vs ytterligare undersökning för att möjliggöra tidig upptĂ€ckt av skadliga exponeringar. Denna studie syftar till att bedöma förekomsten, kĂ€llan och mobiliseringsmekanismerna för arsenik i vissa dricksvattenkĂ€llor i Lake Victoria Basin, i norra Tanzania. LandsbygdssamhĂ€llen som Ă€r kĂ€nda för hantverksmĂ€ssiga och storskaliga guldgruva arbeten var mĂ„let för den nuvarande studien. Femtiofyra vattenprover samlades frĂ„n kĂ€llvatten, borehĂ„lsvatten, floder och grundbrunn i Mara och Geita-regionen under oktober 2016. pH, redoxpotential (Eh), temperatur och elektrisk konduktivitet (EC) mĂ€ttes i fĂ€lt. Vattenprovernas koncentration av an- och katjoner, spĂ„rĂ€mnen (bl.a. arsenik), As(III) samt löst organiskt kol (DOC) analyserades i Sverige pĂ„ Kungliga Tekniska Högskolan (KTH). Femtiotre procent av det provtagna vattnet överensstĂ€mmer inte med WHO:s rekommenderade grĂ€ns pĂ„ 10 ÎŒg / l, vilket utgör en allvarlig hĂ€lsorisk fö vissa landsbygdssamhĂ€len i Victoria-sjö. Den geografiska fördelningen av As i det undersökta omrĂ„det Ă€r högst heterogen och pĂ„verkas huvudsakligen av lokal geologi och nĂ€rhet till gruvplatserna (ca <5km). LĂ€gre As-nivĂ„r i borehĂ„l Ă€n i floder och grunda brunnar visar att föroreningar av drĂ€nering pĂ„grund av gruvverksamhet och föeslĂ„r att djupt grundvatten (> 40m) i allmĂ€het utgör en kĂ€lla till sĂ€krare dricksvatten. DĂ€remot, visar denna studie att flera geokemiska processer kontrollerar förutbestĂ€mmelse och röligheten för As, nĂ€ det har blivit frislĂ€ppts ut i vattenmiljö. Stora skillnader mellan fĂ€lt- och labbmĂ€ningar av As indikerar en stark partition av metalloid i partikelfraktionen. Som avslöjas av geokemisk modellering antas, samutfĂ€llning med jĂ€rn / aluminiumhydroxider och adsorption pĂ„ lermineraler vara de huvudsakliga sĂ€nkorna fö upplöst As. Dessutom antyder en bra matchning mellan toppar i As och upplösta organiska kolkoncentrationer att komplexbildning med humana och fulviska syror Ă€r ansvarig för föbĂ€ttrad rölighet

    Geochemical Investigation of Arsenic in Drinking Water Sources in Proximity of Gold Mining Areas within the Lake Victoria Basin, in Northern Tanzania

    No full text
    Access to safe drinking water is a challenge for rural communities in many developing countries. Drinking contaminated water endangers human health and impairs social and economic development. Arsenic (As) is a metalloid widely distributed into the environment and is highly toxic in its trivalent inorganic form. The natural occurrence of As in groundwater used for drinking has been associated to the insurgence of skin disorders and respiratory diseases in many parts of the world. Arsenic is frequently found in the form of sulphide in gold deposits. Human exposure to As via drinking water has resulted from gold mining activities in some instances in USA, Asia, South America and Africa. The problem of As in drinking water has been brought to attention in Tanzania only few years ago and further investigation are therefore needed to enable an early detection of harmful exposures. This study aims to assess occurrence, source and mobilization mechanisms of As in some drinking water sources within the Lake Victoria Basin, in Northern Tanzania. Rural communities living in areas known for artisanal and large-scale gold mining activities were the target of the present study. Fifty-four water samples were collected from a variety of drinking water sources (spring, borehole, river and shallow well) in Mara and Geita region during October 2016. pH, electrical conductivity (EC), Redox potential (Eh) and As were measured in situ. Major ions, dissolved organic carbon (DOC) and trace elements, including As, were analysed in the sampled water at KTH-Royal Institute of Technology, in Sweden. 53% of the sampled water do not comply with the WHO recommended limit of 10 ÎŒg/L, representing a serious health risk for some rural communities within the Lake Victoria Basin. The spatial distribution of As in the area under investigation is highly heterogeneous and it is mainly influenced by local geology and proximity to the mining sites (approx. < 5 km). Lower As levels in boreholes than in rivers and shallow wells indicates contamination of surface drainage by mining activities and suggest that deep groundwater ( > 40 m) generally represent a source of safer drinking water. The field-measured Redox potential indicates oxidising conditions, suggesting that oxidation-dissolution of arsenic sulphide minerals is a major mechanism of arsenic mobilization in groundwater. However, this study reveals that several geochemical processes control fate and mobility of As, once it has been released into the aquatic environment. Large discrepancies between field and laboratory measurements of As indicates a strong partition of the metalloid into the particulate fraction. As revealed by the geochemical modelling, co-precipitation with iron /aluminium hydroxides and adsorption on clay minerals are presumed to be the major sinks for dissolved As. Moreover, a good match between peaks in As and dissolved organic carbon concentrations suggests that complexation by humic acids is responsible for enhanced As mobility. Overall, the present study has led to a better understanding of the problem of arsenic in proximity of gold mining areas in Tanzania and it calls for the development of affordable and sustainable solutions which would provide safe drinking water to the affected population.TillgĂ„ngen till rent, sĂ€kert vatten Ă€r en utmaning pĂ„ landsbygdssamhĂ€llen i mĂ„nga utvecklingslĂ€nder. ÅtgĂ„ng pĂ„ förorenat vatten riskerar mĂ€nniskors hĂ€lsa och skadar social och ekonomisk utveckling. Naturlig förekomst av arsenik (As) i grundvatten Ă€r ett globalt miljöproblem, vilket utgör en allvarlig risk för mĂ€nniskors hĂ€lsa pĂ„ grund av metalloidens höga toxicitet. Med tanke pĂ„ att arsenic sulfids mineraler Ă€r en viktigt del av guld insĂ€ttning, har guldgruva aktiviteter anvisas som en orsak till att föroreningar av drĂ€nering och grundvatten i flera lĂ€nder. Problemet med As i dricksvatten har uppmĂ€rksammats i Tanzania för nĂ„gra Ă„r sedan och det krĂ€vs ytterligare undersökning för att möjliggöra tidig upptĂ€ckt av skadliga exponeringar. Denna studie syftar till att bedöma förekomsten, kĂ€llan och mobiliseringsmekanismerna för arsenik i vissa dricksvattenkĂ€llor i Lake Victoria Basin, i norra Tanzania. LandsbygdssamhĂ€llen som Ă€r kĂ€nda för hantverksmĂ€ssiga och storskaliga guldgruva arbeten var mĂ„let för den nuvarande studien. Femtiofyra vattenprover samlades frĂ„n kĂ€llvatten, borehĂ„lsvatten, floder och grundbrunn i Mara och Geita-regionen under oktober 2016. pH, redoxpotential (Eh), temperatur och elektrisk konduktivitet (EC) mĂ€ttes i fĂ€lt. Vattenprovernas koncentration av an- och katjoner, spĂ„rĂ€mnen (bl.a. arsenik), As(III) samt löst organiskt kol (DOC) analyserades i Sverige pĂ„ Kungliga Tekniska Högskolan (KTH). Femtiotre procent av det provtagna vattnet överensstĂ€mmer inte med WHO:s rekommenderade grĂ€ns pĂ„ 10 ÎŒg / l, vilket utgör en allvarlig hĂ€lsorisk fö vissa landsbygdssamhĂ€len i Victoria-sjö. Den geografiska fördelningen av As i det undersökta omrĂ„det Ă€r högst heterogen och pĂ„verkas huvudsakligen av lokal geologi och nĂ€rhet till gruvplatserna (ca <5km). LĂ€gre As-nivĂ„r i borehĂ„l Ă€n i floder och grunda brunnar visar att föroreningar av drĂ€nering pĂ„grund av gruvverksamhet och föeslĂ„r att djupt grundvatten (> 40m) i allmĂ€het utgör en kĂ€lla till sĂ€krare dricksvatten. DĂ€remot, visar denna studie att flera geokemiska processer kontrollerar förutbestĂ€mmelse och röligheten för As, nĂ€ det har blivit frislĂ€ppts ut i vattenmiljö. Stora skillnader mellan fĂ€lt- och labbmĂ€ningar av As indikerar en stark partition av metalloid i partikelfraktionen. Som avslöjas av geokemisk modellering antas, samutfĂ€llning med jĂ€rn / aluminiumhydroxider och adsorption pĂ„ lermineraler vara de huvudsakliga sĂ€nkorna fö upplöst As. Dessutom antyder en bra matchning mellan toppar i As och upplösta organiska kolkoncentrationer att komplexbildning med humana och fulviska syror Ă€r ansvarig för föbĂ€ttrad rölighet
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