Protective role for collectin‐11 in rheumatoid arthritis in mice

OBJECTIVE. Collectin-11 (CL-11) is a soluble C-type lectin, a mediator of innate immunity. Its role in autoimmune disorders is unknown. The goal of this study was to determine the role of CL-11 in a mouse model of rheumatoid arthritis (RA). METHODS. A murine collagen-induced arthritis (CIA) model, combining both gene deletion of Colec11 and recombinant (rCL-11) treatment approaches were employed. Joint inflammation and tissue destruction, circulating levels of inflammatory cytokines and adaptive immune responses were assessed in CIA mice. Splenic CD11c(+) cells were used to examine the influence of CL-11 on antigen presenting cell (APC) function. Serum levels of CL-11 in RA patients were also examined. RESULTS. Colec11(−/−) mice developed more severe arthritis than WT mice (as determined by disease incidence, clinical arthritis scores and histopathology; P<0.05). Disease severity is associated with significantly enhanced APC activation, Th1/Th17 responses, pathogenic IgG2a production and joint inflammation, as well as elevated circulating levels of inflammatory cytokines. In vitro analysis of CD11c(+) cells revealed that CL-11 is critical for suppression of APC activation and function. Pharmacological treatment of mice with rCL-11 reduced the severity of CIA in mice. Analysis of human blood samples revealed that serum levels of CL-11 was lower in RA patients (n=51) compared to healthy controls (n=53), a serum CL-11 reduction also displays a negative relationship with DAS28, ESR and CRP (P<0.05). CONCLUSION. Our findings demonstrate a novel role for CL-11 in protection against RA, suggesting the underlying mechanism involved suppression of APC activation and subsequent T cell responses

Prevalence Distribution and Risk Factors for Schistosoma hematobium Infection among School Children in Blantyre, Malawi

Schistosoma hematobium infection is a parasitic infection endemic in Malawi. Schistosomiasis usually shows a focal distribution of infection and it is important to identify communities at high risk of infection and assess effectiveness of control programs. We conducted a survey in one district in Malawi to determine prevalence and factors associated with S. hematobium infection among primary school pupils. Using a questionnaire, information on history of passing bloody urine and known risk factors associated with infection was collected. Urine samples were collected and examined for S. hematobium eggs. One thousand one hundred and fifty (1,150) pupils were interviewed, and out of 1,139 pupils who submitted urine samples, 10.4% were infected. Our data showed that male gender, child's knowledge of an existing open water source (includes river, dam, springs, lake, etc.) in the area, history of urinary schistosomiasis in the past month, distance of less than 1 km from school to nearest open water source and age 8–10 years compared to those 14 years and older were independently associated with infection. These findings suggest that children attending schools in close proximity to open water sources are at increased risk of infection

Challenges and innovations brought about by the Covid-19 pandemic regarding medical and pharmacy education especially in Africa and implications for the future

Background: Multiple measures introduced early to restrict COVID-19 have dramatically impacted the teaching of medical and pharmacy students, exacerbated by the lack of infrastructure and experience with e-learning at the start of the pandemic. In addition, the costs and reliability of the Internet across Africa pose challenges alongside undertaking clinical teaching and practical programmes. Consequently, there is a need to understand the many challenges and how these were addressed, given increasingly complex patients, to provide future direction. Method: An exploratory study was conducted among senior-level medical and pharmacy educators across Africa, addressing four key questions, including the challenges resulting from the pandemic and how these were dealt with. Results: Staff and student members faced multiple challenges initially, including adapting to online learning. In addition, concerns with the lack of equipment (especially among disadvantaged students), the costs of Internet bundles, and how to conduct practicals and clinical teaching. Multiple activities were undertaken to address these challenges. These included training sessions, developing innovative approaches to teaching, and seeking ways to reduce Internet costs. Robust approaches to practicals, clinical teaching, and assessments have been developed. Conclusions: Appreciable difficulties to teaching arising from the pandemic are being addressed across Africa. Research is ongoing to improve education and assessments

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia

Diseño de una central fotovoltaica de 10 kw para suministrar energía eléctrica al caserío la devora-pariñas-talara

En el presente trabajo de investigaciÛn se realizÛ el diseÒo de una central fotovoltaica de 10Kw para abastecer de energÌa elÈctrica a una comunidad de aproximadamente 20 familias que se encuentran ubicadas en el caserío “La Devora”, distrito de Pariñas, provincia de Talara-Per˙. Para desarrollar el diseÒo de la central Fotovoltaica de 10 Kw, se determinÛ la potencia solar de la ubicaciÛn del caserÌo utilizando el software Power Data Access Viewer, con el cual se determinÛ la irradiaciÛn solar horizontal del mes m·s desfavorable del aÒo, el cual resulto ser de 4.99 KWh/m2/dÌa. Con estos valores de IrradiaciÛn solar en el ·rea de estudio y tambiÈn utilizando encuestas para determinar el consumo elÈctrico de los pobladores del CaserÌo y reuniones para determinar la problem·tica de sus pobladores producto de la falta de red elÈctrica convencional, se realizÛ el DiseÒo de la Central Fotovoltaica, utilizando C·lculos de IngenierÌa, obteniendo como resultados principales que la Central tendr· 45 paneles de 540 Wp, 64 baterÌas de 300 Ah/12v, 5 reguladores de carga y 3 inversores 3000 W. Y finalmente, con las caracterÌsticas y cantidades Totales de la Central Fotovoltaica, se procediÛ a estimar la inversiÛn inicial para su ConstrucciÛn; y se realizÛ el flujo de caja del Proyecto, con la finalidad de obtener los Indicadores EconÛmicos, los cuales resultaron ser: VAN de S/.9,345.87 (soles) y un TIR de 12%, por lo que se puede concluir que el proyecto serÌa factible.TesisInfraestructura, Tecnología y Medio Ambient

Viral CNS infections in children from a malaria-endemic area of Malawi: a prospective cohort study

Background Fever with reduced consciousness is an important cause of hospital admission of children in sub-Saharan Africa, with high mortality. Cerebral malaria, diagnosed when acute Plasmodium falciparum infection and coma are recorded with no other apparent reason, is one important cause. We investigated whether viruses could also be an important cause of CNS infection in such patients, and examined the relative contribution of viral pathogens and malaria parasitaemia. Methods We did a prospective cohort study in Blantyre, Malawi. From March 1, 2002, to Aug 31, 2004, we enrolled children aged between 2 months and 15 years who were admitted to hospital with suspected non-bacterial CNS infections. Children with a cerebrospinal fluid (CSF) white cell count of less than 1000 cells per mu L and negative bacterial microscopy and culture were deemed to have suspected viral CNS infection. Blood was examined for asexual forms of P falciparum. PCR was done on CSF or on post-mortem brain biopsy specimens to detect 15 viruses known to cause CNS infection. Findings Full outcome data were available for 513 children with suspected viral CNS infection, of whom 94 (18%) died. 163 children (32%) had P falciparum parasitaemia, of whom 34 (21%) died. At least one virus was detected in the CNS in 133 children (26%), of whom 43 (33%) died. 12 different viruses were detected; adenovirus was the most common, affecting 42 children; mumps, human herpes virus 6, rabies, cytomegalovirus, herpes simplex virus 1, and enterovirus were also important. 45 (9%) of the 513 children had both parasitaemia and viral infection, including 27 (35%) of 78 diagnosed clinically with cerebral malaria. Children with dual infection were more likely to have seizures than were those with parasitaemia alone, viral infection only, or neither (p<0.0001). 17 (38%) of the 45 children with dual infection died, compared with 26 (30%) of 88 with viral infection only, 17 (14%) of 118 with parasitaemia only, and 34 (13%) of 262 with neither (p<0.0001). Logistic regression showed children with a viral CNS infection had a significantly higher mortality than did those who did not have a viral CNS infection (p=0.001). Interpretation Viral CNS infections are an important cause of hospital admission and death in children in Malawi, including in children whose coma might be attributed solely to cerebral malaria. Interaction between viral infection and parasitaemia could increase disease severity

Assessing differences in groundwater recharge patterns under tilled and zero-till systems using a combination of water level observations, hydrochemistry, age tracers (CFCS, SF6), and isotopes

Under the pressure of growing populations and risks to food security by increased extreme weather events (droughts and floods), many sub-Saharan countries have promoted a shift to climate-smart agricultural systems such as conservation agriculture (CA). The core principles of CA, along with crop diversification/rotation, comprise minimum tillage or zero-till and mulching, both of which may affect water retention in the upper soil layers. One of the observed benefits of CA is increased crop resilience in periods of drought, which is important to improve food security in this water scarce region. However, effects of CA on groundwater recharge, for example changes to quantities, timing or altered recharge pathways have scarcely been investigated, and need consideration because they may affect not only groundwater renewability, but potentially also contaminant transport and therefore groundwater quality. In this study, we introduce a multi-disciplinary approach at three sites in Zambia, Zimbabwe and Malawi using a suite of investigation methods to characterize recharge patterns under CA and conventionally tilled plots. In our presented setup, high-resolution (30 minutes) groundwater level and weather data are complemented by monthly groundwater chemistry (major, minor, and trace elements) and stable water isotope analysis from shallow monitoring boreholes over a monitoring period of multiple (2—3) recharge seasons. Annual repeat measurements of residence time tracers (CFCs and SF6) add additional information on groundwater age. Information on water movement in the vadose zone are obtained via in-situ soil moisture measurements, and time-lapse electrical resistivity tomography (ERT) enables an integrated assessment of groundwater recharge processes. Preliminary data analysis indicates that differences in timing and pattern of groundwater recharge between conventionally tilled and CA treatment plots can be observed. The results of this study can inform policy and decision makers and further our understanding of the effects promoted land use changes may have on local groundwater resources

Assessing differences in groundwater recharge flows under conservation agriculture and conventional tillage

Under the pressure of growing populations and risks to food security by increased extreme weather events (droughts and floods), many countries, particularly in semi-arid and arid regions, such as sub-Saharan Africa have promoted a shift to climate-smart agricultural systems such as conservation agriculture (CA). The core principles of CA, along with crop diversification/rotation, comprise minimum tillage and mulching, and previous studies indicate positive effects of these practices on soil moisture balance. However, effects of CA on groundwater recharge, for example changes to quantities, timing or altered recharge pathways have scarcely been investigated in the sub-Sahara environment, and need consideration because they may affect not only groundwater renewability, but potentially also contaminant transport and therefore groundwater quality. In this study, we introduce a plot-scale approach at three sites in Zambia, Zimbabwe and Malawi using a suite of investigation methods to characterize recharge patterns under CA and conventionally tilled plots. In our presented setup, high-resolution (30 minutes) groundwater level and weather data are complemented by monthly groundwater chemistry (major, minor, and trace elements) and stable water isotope analysis from shallow monitoring boreholes over a monitoring period of multiple (2—3) recharge seasons. Annual repeat measurements of residence time tracers (CFCs and SF6) add additional information on groundwater age. Preliminary data analysis indicates that differences in onset and pattern of groundwater recharge between conventionally tilled and CA treatment plots can be observed, which could be valuable information for example in informing best management such as timing of fertilizer and pesticide application. The results of this study can therefore inform policy and decision makers and further our understanding of the effects promoted land use changes may have on local groundwater resources