3,949 research outputs found

    Short communication: Use of calcium sulphate dihydrate as an alternative to the conventional use of aluminium sulphate in the primary treatment of wastewater

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    The application of calcium sulphate dihydrate (CaSO4.2H2O) as a coagulant-flocculant alternative to the conventional use of aluminium sulphate in the primary treatment of wastewater was evaluated using a jar test apparatus. Samples from the State Water Commission (CEA) in Queretaro, Mexico, were collected for the experiments. Turbidity and pH were measured before and after applying the calcium sulphate dihydrate (CaSO4.2H2O). Turbidity readings obtained for the doses of 4 gE.-1 of aluminium sulphate varied from 3.91 to 3.87. The corresponding water pH was 3.90, giving the water an acidic character. Use of aluminium sulphate in the clarification of wastewater, thus, has financial and environmental implications due to the need to raise the pH of the treated water to 6.5.8.5, the recommended optimum interval for the physical-chemical-biological removal of pollutants. By contrast, calcium sulphate di-hydrate (CaSO4E2H2O) (gypsum) doses of 1, 1.5 and 2 gE.-1 resulted in a pH of between 7.04 and 7.51 repeatedly. These findings suggest that the application of calcium sulphate di-hydrate (CaSO4.2H2O) as coagulant-flocculant, followed by the process of sedimentation, may be a suitable alternative for the clarification of wastewater. However, the turbidity reported for the same doses was 74.05, 80.5 and 74.5 NTU, respectively, well above the international standard of 5 NTU. The effect of gypsum on turbidity warrants further research

    Cooperation, collective action, and the archeology of large-scale societies

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    Archeologists investigating the emergence of large-scale societies in the past have renewed interest in examining the dynamics of cooperation as a means of understanding societal change and organizational variability within human groups over time. Unlike earlier approaches to these issues, which used models designated voluntaristic or managerial, contemporary research articulates more explicitly with frameworks for cooperation and collective action used in other fields, thereby facilitating empirical testing through better definition of the costs, benefits, and social mechanisms associated with success or failure in coordinated group action. Current scholarship is nevertheless bifurcated along lines of epistemology and scale, which is understandable but problematic for forging a broader, more transdisciplinary field of cooperation studies. Here, we point to some areas of potential overlap by reviewing archeological research that places the dynamics of social cooperation and competition in the foreground of the emergence of large-scale societies, which we define as those having larger populations, greater concentrations of political power, and higher degrees of social inequality. We focus on key issues involving the communal-resource management of subsistence and other economic goods, as well as the revenue flows that undergird political institutions. Drawing on archeological cases from across the globe, with greater detail from our area of expertise in Mesoamerica, we offer suggestions for strengthening analytical methods and generating more transdisciplinary research programs that address human societies across scalar and temporal spectra

    Urban Movement and Alcohol Intake Strongly Predict Defaulting from Tuberculosis Treatment: An Operational Study

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    BACKGROUND: High levels of defaulting from treatment challenge tuberculosis control in many African cities. We assessed defaulting from tuberculosis treatment in an African urban setting. METHODS: An observational study among adult patients with smear-positive pulmonary tuberculosis receiving treatment at urban primary care clinics in Kampala, Uganda. Defaulting was defined as having missed two consecutive monthly clinic visits while not being reported to have died or continued treatment elsewhere. Defaulting patients were actively followed-up and interviewed. We assessed proportions of patients abandoning treatment with and without the information obtained through active follow-up and we examined associated factors through multivariable logistic regression. RESULTS: Between April 2007 and April 2008, 270 adults aged ≥15 years were included; 54 patients (20%) were recorded as treatment defaulters. On active follow-up vital status was established of 28/54 (52%) patients. Of these, 19 (68%) had completely stopped treatment, one (4%) had died and eight (29%) had continued treatment elsewhere. Extrapolating this to all defaulters meant that 14% rather than 20% of all patients had truly abandoned treatment. Daily consumption of alcohol, recorded at the start of treatment, predicted defaulting (adjusted odds ratio [OR(adj)] 4.4, 95%CI 1.8-13.5), as did change of residence during treatment (OR(adj) 8.7, 95%CI 1.8-41.5); 32% of patients abandoning treatment had changed residence. CONCLUSIONS: A high proportion of tuberculosis patients in primary care clinics in Kampala abandon treatment. Assessing change of residence during scheduled clinic appointments may serve as an early warning signal that the patient may default and needs adherence counseling

    Controls on gut phosphatisation : the trilobites from the Weeks Formation Lagerstätte (Cambrian; Utah)

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    Despite being internal organs, digestive structures are frequently preserved in Cambrian Lagerstätten. However, the reasons for their fossilisation and their biological implications remain to be thoroughly explored. This is particularly true with arthropods--typically the most diverse fossilised organisms in Cambrian ecosystems--where digestive structures represent an as-yet underexploited alternative to appendage morphology for inferences on their biology. Here we describe the phosphatised digestive structures of three trilobite species from the Cambrian Weeks Formation Lagerstätte (Utah). Their exquisite, three-dimensional preservation reveals unique details on trilobite internal anatomy, such as the position of the mouth and the absence of a differentiated crop. In addition, the presence of paired pygidial organs of an unknown function is reported for the first time. This exceptional material enables exploration of the relationships between gut phosphatisation and the biology of organisms. Indeed, soft-tissue preservation is unusual in these fossils as it is restricted to the digestive structures, which indicates that the gut played a central role in its own phosphatisation. We hypothesize that the gut provided a microenvironment where special conditions could develop and harboured a source of phosphorus. The fact that gut phosphatization has almost exclusively been observed in arthropods could be explained by their uncommon ability to store ions (including phosphorous) in their digestive tissues. However, in some specimens from the Weeks Formation, the phosphatisation extends to the entire digestive system, suggesting that trilobites might have had some biological particularities not observed in modern arthropods. We speculate that one of them might have been an increased capacity for ion storage in the gut tissues, related to the moulting of their heavily-mineralised carapace

    Acute retroperitoneal bleeding due to inferior mesenteric artery aneurysm: Case report

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    <p>Abstract</p> <p>Background</p> <p>Visceral artery aneurysms (VAA), although uncommon, are increasingly being detected. We describe a case of spontaneous retroperitoneal hemorrhage from a ruptured IMA aneurysm associated with stenosis of the superior mesenteric artery (SMA) and celiac trunk, successfully treated with surgery.</p> <p>Methods</p> <p>A 65-year-old man presented with abdominal pain and hypovolemic shock. Abdominal CT scan showed an aneurysm of the inferior mesenteric artery with retroperitoneal hematoma. In addition, an obstructive disease of the superior mesenteric artery and celiac axis was observed.</p> <p>Results</p> <p>Upon emergency laparotomy a ruptured inferior mesenteric artery aneurysm was detected. The aneurysm was excised and the artery reconstructed by end-to-end anastomosis.</p> <p>Conclusions</p> <p>This report discusses the etiology, presentation, diagnosis and case management of inferior mesenteric artery aneurysms.</p

    A transient homotypic interaction model for the influenza A virus NS1 protein effector domain

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    Influenza A virus NS1 protein is a multifunctional virulence factor consisting of an RNA binding domain (RBD), a short linker, an effector domain (ED), and a C-terminal 'tail'. Although poorly understood, NS1 multimerization may autoregulate its actions. While RBD dimerization seems functionally conserved, two possible apo ED dimers have been proposed (helix-helix and strand-strand). Here, we analyze all available RBD, ED, and full-length NS1 structures, including four novel crystal structures obtained using EDs from divergent human and avian viruses, as well as two forms of a monomeric ED mutant. The data reveal the helix-helix interface as the only strictly conserved ED homodimeric contact. Furthermore, a mutant NS1 unable to form the helix-helix dimer is compromised in its ability to bind dsRNA efficiently, implying that ED multimerization influences RBD activity. Our bioinformatical work also suggests that the helix-helix interface is variable and transient, thereby allowing two ED monomers to twist relative to one another and possibly separate. In this regard, we found a mAb that recognizes NS1 via a residue completely buried within the ED helix-helix interface, and which may help highlight potential different conformational populations of NS1 (putatively termed 'helix-closed' and 'helix-open') in virus-infected cells. 'Helix-closed' conformations appear to enhance dsRNA binding, and 'helix-open' conformations allow otherwise inaccessible interactions with host factors. Our data support a new model of NS1 regulation in which the RBD remains dimeric throughout infection, while the ED switches between several quaternary states in order to expand its functional space. Such a concept may be applicable to other small multifunctional proteins

    LA INMIGRANTE Y SU SALUD, UN CAMINO POR RECORRER EN EL S. XXI

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    Introduction The demand for health care in Murcia has made us question how immigrants perceive our health care system. Thus the importance of observing the behavior of immigrants, as they face obstacles appearing because they are women and belong to a different culture, an issue that can be difficult for health care workers. Methodology: The study was conducted with a sample of 41 female immigrants in the Murcia region. Five introductory interviews were carried out as an introductory tool in this observational descriptive study. After obtaining the results some forms were filled out consisting of closed questions concerning the attention given, obstacles and gender issues when it comes to receiving their health care. As a criterion of exclusion, there was an absence of males during the questioning so as not to affect the response of the interviewee. Discussion The vast majority of those interviewed have difficulty communicating with health care staff. Dissatisfaction with the service provided could arise. It shows the great importance of a mediator between professionals and female immigrants. Therefore, health care services should be open to all people in our society, not only in situations of illness but also to improve health. Conclusions • Encourage the need for a multicultural mediator in all places where health care is provided. •Required that health professionals who provide care should be trained in cultural aspects. •Health policy towards immigration groups should be implemented.Introducción La demanda de atención sanitaria en nuestra Región nos ha llevado a cuestionarnos cómo las inmigrantes perciben nuestra atención sanitaria, por ello la importancia de observar el comportamiento de las inmigrantes ante los obstáculos que se les presentan por el hecho de ser mujeres y de pertenecer a una cultura diferente y que pueda ser objeto de dificultad para el personal sanitario. Metodología El estudio se ha realizado con una muestra de 41 mujeres inmigrantes de la Región de Murcia de tipo observacional descriptivo, en el que se hicieron 5 entrevistas como herramienta introductoria. Tras los resultados obtenidos se han llevado a cabo unos formularios que constan de preguntas cerradas referentes a la atención prestada, obstáculos y razón de sexo a la hora de recibir su atención sanitaria. Como criterio de exclusión, ausencia del género masculino durante las preguntas-respuestas para no influir en la respuesta de la entrevistada. Discusión La gran mayoría de las entrevistadas presentan dificultades para comunicarse con el personal sanitario. Pudiendo provocar una insatisfacción del servicio que se le presta. Se muestra la gran importancia de una persona mediadora entre profesionales y mujeres inmigrantes. Por tanto, los servicios de Salud deben estar abiertos a todas las personas que configuran nuestra sociedad, no solamente en situación de enfermedad sino también para mejorar la salud. Conclusiones • Potenciar la necesidad de un mediador multicultural en todos los centros donde se presta atención sanitaria. • Exigencia curricular de formación en aspectos culturales a los profesionales sanitarios que prestan sus cuidados. • Se debería proyectar la política sanitaria hacia los grupos inmigratorios

    Psychometric evaluation and validation of the Postpartum Specific Anxiety Scale for the Spanish-speaking population: PSAS-ES

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    Objective: The transition to motherhood is a period of risk for the development of mood disorders. Postpartum anxiety has not been as thoroughly studied as other emotional disorders despite its impact on mothers and their babies. The absence of standardized programmes for early detection and specific tools for its diagnosis means postpartum anxiety is often underestimated or overshadowed. This study aimed to translate and validate the Postpartum Specific Anxiety Scale [PSAS] for the Spanish population and to analyse its reliability as an exploratory tool for specific anxiety in mothers. Method: Four stages were followed in this research: translation and back-translation to obtain the Spanish version [PSAS-ES]; preliminary pilot study to explore the comprehensibility and ease of responding the items (n = 53); convergent validity analyses (n = 644); and test-retest reliability (n = 234). Results: The PSAS-ES has shown to have good acceptability, convergent validity and high internal consistency with a Cronbach's α coefficient of 0.93 for the overall scale of PSAS. The four factors had good reliability. The results of test-retest was 0.86, indicating excellent stability over time in the first 16 weeks. Conclusion: The psychometric results show that the PSAS-ES is a valid tool to explore and detect anxiety in Spanish mothers between 0 and 16 weeks postpartum
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