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CSRD Technical Exchange: ICPAC and National Climate Maprooms â Existing and New Tools for Drought Monitoring and Forecasting in Eastern Africa
In 2005, the International Research Institute for Climate and Society published its assessment of key gaps in the use of climate information for health, agriculture, water and other sectors in countries across Africa. The results from the report were less than stellar. After an extensive review of use of climate information in the development sectors of Africa, the authors concluded that the continent suffered from âmarket atrophyâ â the reinforcing effect of inadequate effective supply of climate information and weak effective demand. Twelve years later, organizations such as the IRI, CSRD program, CCAFS, ICPAC, and UKMO have made enormous strides at increasing both climate information supply and effective demand through the implementation of climate data platforms and the organizing of capacity-building seminars. In order to capitalize on the presence of the many climate and sector experts from across the IGAD
region, the organizations above held a joint event, the CSRD Technical Exchange: ICPAC and National Climate Maprooms â Existing and New Tools for Drought Monitoring and Forecasting in Eastern Africa, in Zanzibar on August 23-25, 2017, immediately after the 47th Greater Horn of Africa Climate Outlook Forum (GHACOF47). The workshop was designed to offer potential and existing users a platform to voice their needs for the development and better use of historical, monitored and forecast information
for the management of drought across climate-sensitive sectors
Nitrogen Management in Grasslands and Forage-Based Production SystemsâRole of Biological Nitrification Inhibition (BNI)
Nitrogen (N), being the most critical and essential nutrient for plant growth, largely determines the productivity in both extensive- and intensive- grassland systems. Nitrification and denitrification processes in the soil are the primary drivers generating reactive-N: NO3-, N2O, and NO, and is largely responsible for N-loss and degradation of grasslands. Suppressing nitrification can thus facilitate the retention of soil-N to sustain long-term productivity of grasslands and forage-based production systems. Certain plants can suppress soil nitrification by releasing inhibitors from roots, a phenomenon termed âbiological nitrification inhibitionâ (BNI). Recent methodological developments (e.g. bioluminescence assay to detect BNIs from plant-root systems) led to significant advances in our ability to quantify and characterize BNI function in pasture grasses. Among grass-pastures, BNI-capacity is strongest in low-N adapted grasses such as Brachiaria humidicola and weakest in high-N environment grasses such as Italian ryegrass (Lolium perenne) and B. brizantha. The chemical identity of some of the BNIs produced in plant tissues and released from roots has now been established and their mode of inhibitory action determined on nitrifying bacteria Nitrosomonas. Synthesis and release of BNIs is a highly regulated and localized process, triggered by the presence of NH4+ in the rhizosphere, which facilitates the release of BNIs close to soil-nitrifier sites. Substantial genotypic variation is found for BNI-capacity in B. humidicola, which opens the way for its geneticmanipulation. Field studies suggest that Brachiaria grasses suppress nitrification and N2O emissions from soil. The potential for exploiting BNI function (from a genetic improvement and a system perspective) to develop production systems that are low-nitrifying, low N2O-emitting, economically efficient and ecologically sustainable, will be the subject of discussion
Adverse Effect of Nano-Silicon Dioxide on Lung Function of Rats with or without Ovalbumin Immunization
BACKGROUND: The great advances of nanomaterials have brought out broad important applications, but their possible nanotoxicity and risks have not been fully understood. It is confirmed that exposure of environmental particulate matter (PM), especially ultrafine PM, are responsible for many lung function impairment and exacerbation of pre-existing lung diseases. However, the adverse effect of nanoparticles on allergic asthma is seldom investigated and the mechanism remains undefined. For the first time, this work investigates the relationship between allergic asthma and nanosized silicon dioxide (nano-SiOâ). METHODOLOGY/PRINCIPAL FINDINGS: Ovalbumin (OVA)-treated and saline-treated control rats were daily intratracheally administered 0.1 ml of 0, 40 and 80 ”g/ml nano-SiOâ solutions, respectively for 30 days. Increased nano-SiOâ exposure results in adverse changes on inspiratory and expiratory resistance (Ri and Re), but shows insignificant effect on rat lung dynamic compliance (Cldyn). Lung histological observation reveals obvious airway remodeling in 80 ”g/ml nano-SiOâ-introduced saline and OVA groups, but the latter is worse. Additionally, increased nano-SiOâ exposure also leads to more severe inflammation. With increasing nano-SiOâ exposure, IL-4 in lung homogenate increases and IFN-Îł shows a reverse but insignificant change. Moreover, at a same nano-SiOâ exposure concentration, OVA-treated rats exhibit higher (significant) IL-4 and lower (not significant) IFN-Îł compared with the saline-treated rats. The percentages of eosinophil display an unexpected result, in which higher exposure results lower eosinophil percentages. CONCLUSIONS/SIGNIFICANCE: This was a preliminary study which for the first time involved the effect of nano-SiOâ to OVA induced rat asthma model. The results suggested that intratracheal administration of nano-SiOâ could lead to the airway hyperresponsiveness (AHR) and the airway remolding with or without OVA immunization. This occurrence may be due to the Th1/Th2 cytokine imbalance accelerated by the nano-SiOâ through increasing the tissue IL-4 production
Intravitreal vs. subtenon triamcinolone acetonide for the treatment of diabetic cystoid macular edema
<p>Abstract</p> <p>Background</p> <p>To assess the efficacy of the intravitreal (IVT) injection of Triamcinolone Acetonide (TA) as compared to posterior subtenon (SBT) capsule injection for the treatment of cystoid diabetic macular edema.</p> <p>Methods</p> <p>Fourteen patients with type II diabetes mellitus and on insulin treatment, presenting diffuse cystoid macular edema were recruited. Before TA injection all focal lakes were treated by laser photocoagulation. In the same patients one eye was assigned to 4 mg IVT injection of TA and the fellow eye was then treated with 40 mg SBT injection of TA. Before and one, three and six months after treatment we measured visual acuity with ETDRS chart as well as thickness of the macula with optical coherence tomography (OCT) and intraocular pressure (IOP).</p> <p>Results</p> <p>The eyes treated with an IVT injection displayed significant improvement in visual acuity, both after one (0.491 ± 0.070; p < 0.001) and three months (0.500 ± 0.089; p < 0.001) of treatment. Significant improvement was displayed also in eyes treated with an SBT injection, again after one (0.455 ± 0.069; p < 0.001) and three months (0.427 ± 0.065; p < 0.001). The difference between an IVT injection (0.809 ± 0.083) and SBT injection (0.460 ± 0.072) becomes significant six months after the treatment (p < 0.001).</p> <p>Macular thickness of the eyes treated with IVT injection was significantly reduced both after one (222.7 ± 13.4 Όm; p < 0.001) and after three months (228.1 ± 10.6 Όm; p < 0.001) of treatment. The eyes treated with SBT injection displayed significant improvement after one (220.1 ± 15.1 Όm; p < 0.001) and after three months (231.3 ± 10.9 Όm; p < 0.001). The difference between the eyes treated with IVT injection (385.2 ± 11.3 Όm) and those treated with SBT injection (235.4 ± 8.7 Όm) becomes significant six months after the treatment (p < 0.001).</p> <p>Intraocular pressure of the eyes treated with IVT injection significantly increased after one month (17.7 ± 1.1 mm/Hg; p < 0.020), three (18.2 ± 1.2 mm/Hg; p < 0.003) and six month (18.1 ± 1.3 mm/Hg; p < 0.007) when compared to baseline value (16.1 ± 1.402 mm/Hg). In the SBT injection eyes we didn't display a significant increase of intraocular pressure after one (16.4 ± 1.2 mm/Hg; p < 0.450), three (16.3 ± 1.1 mm/Hg; p < 0.630) and six months (16.2 ± 1.1 mm/Hg; p < 0.720) when compared to baseline value (16.2 ± 1.3 mm/Hg).</p> <p>Conclusion</p> <p>The parabulbar subtenon approach can be considered a valid alternative to the intravitreal injection.</p> <p>Trial registration</p> <p>Current Controlled Trials <b>ISRCTN67086909</b></p
Estudo biolĂłgico e comportamental de lagartas de Spodoptera frugiperda visando Ă produção de BaculovĂrus spodoptera
A utilização de bioinseticida a base de Spodoptera frugiperda
multiple nucleopolyhedrovirus (SfMNPV) possui potencial para o controle de
Spodoptera frugiperda (Lepidoptera: Noctuidae), porém sua obtenção em larga
escala depende da maximização da produção in vivo. Assim, alguns fatores
biológicos e comportamentais devem ser estudados para aperfeiçoar a
produção de SfMNPV com intuito de disponibilizar um bioinseticida eficiente,
economicamente viĂĄvel e que possa ser usado no manejo de S. frugiperda nos
mais diversos sistemas agrĂcolas. Entre os fatores relacionados ao hospedeiro,
a temperatura e a idade para inoculação do vĂrus sĂŁo de extrema importĂąncia,
pois interferem diretamente no ciclo de vida e na replicação viral. O
comportamento também deve ser avaliado, para evitar condiçÔes de criação do
hospedeiro que favoreçam o canibalismo e causa prejuĂzo na multiplicação in
vivo do SfMNPV. Assim, objetivou-se determinar a melhor condição térmica
para criar as lagartas e a idade ideal, para inocular e multiplicar o vĂrus no
hospedeiro, bem como, verificar a ocorrĂȘncia do comportamento canibal em
lagartas de S. frugiperda. Os experimentos foram conduzidos no LaboratĂłrio de
Controle Microbiano de Insetos do NĂșcleo de Desenvolvimento CientĂfico e
Tecnológico em Manejo Fitossanitårio de Pragas e Doenças (NUDEMAFI),
localizado no Centro de CiĂȘncias AgrĂĄrias da UFES, em Alegre, EspĂrito Santo,
Brasil. A pesquisa foi desenvolvida em duas etapas, a primeira para determinar
a condição térmica e a idade ideais para criar e inocular, respectivamente, o
hospedeiro com o vĂrus, para multiplicação in vivo de SfMNPV. A segunda
etapa foi para avaliar o comportamento canibal de lagartas da espécie S.
frugiperda criadas a 22, 25 e 31°C, inoculadas com SfMNPV quando com
idades de 10, 8 e 4 dias, respectivamente, e mantidas em diferentes
densidades populacionais (5, 10, 25 e 50 lagartas por recipiente). A
mortalidade diminuiu com o aumento da temperatura e da idade do hospedeiro
nas temperaturas de 25, 28 e 31 °C. O aumento na taxa de canibalismo foi
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diretamente proporcional Ă densidade populacional quando as lagartas foram
criadas a 22 °C, inoculadas aos 10 dias de idade e 25 ÂșC, inoculadas aos 8
dias e atingiram 63,5 e 62,5%, respectivamente na densidade populacional de
50 lagartas. Mas, quando as lagartas foram criadas a 31ÂșC e inoculadas com
idade de 4 dias, a densidade populacional nĂŁo afetou o comportamento
canibal, taxa média de 24%, inferior aos outros tratamentos com 50 lagartas
por recipiente. Demonstrando que é viåvel para a multiplicação viral, criar
lagartas a 31 °C e aos 4 dias de idade inocular o vĂrus, podendo a partir de
então colocar até 50 lagartas por recipiente, o que reduz a mão-de-obra
necessĂĄria para individualizar as lagartas e otimiza o espaço fĂsico em uma
biofåbrica. Portanto, se para otimizar o processo produção viral e o serviço em
uma biofåbrica, é preciso maximizar a produção viral, reduzir o tempo de
multiplicação do vĂrus e o canibalismo entre as lagartas, com ausĂȘncia de
contaminação da criação, a temperatura e idade ideais para criação massal de
S. frugiperda e inoculação do vĂrus nas lagartas, respectivamente, visando
produção de baculovĂrus em larga escala sĂŁo de 31 ÂșC e 4 dias
Endothelial dysfunction and diabetes: roles of hyperglycemia, impaired insulin signaling and obesity
Long-term behavioural impact of an integrated home garden intervention: evidence from Bangladesh
Integrated home garden interventions combine training in gardening practices with education about nutrition knowledge. Such interventions have been shown to improve nutrition behaviour in low income countries. However, to date rigorous evidence is lacking for their long-term impact. We test the impact of an integrated home garden intervention on vegetable production and consumption three years after the intervention ended. We analyse three rounds of survey data for 224 control and 395 intervention households in rural Bangladesh. Three years after the intervention, the average impact on vegetable production per household was 43 kg/year (+49% over baseline levels; p < 0.01), and the effect was not statistically different from the impact one year after the intervention, which demonstrates that impact was maintained in the long-term. The impact on the micronutrient supply for iron, zinc, folate and pro-vitamin A from home gardens was maintained in the long term. These impacts may have been driven by the long-term improvements in womenâs nutrition knowledge and gardening practices, explaining the sustainability of the behavioural nutrition change. We also identify positive impacts on womenâs empowerment and womenâs output market participation, highlighting how integrated programs, even if modest in scope, can be drivers of social change
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