A new hotspot for Temminck’s Red Colobus (Piliocolobus badius temminckii) in The Gambia: the feasibility of a community approach to conservation

The geographic range and abundance of Temminck’s red colobus, Piliocolobus badius temminckii, in The Gambia is not well documented. In March 2019, line transect surveys were conducted at a number of data deficient forests in The Gambia to establish species presence or absence, contribute to a greater understanding of the species at a national scale and identify prior- ity sites for conservation. One area around Sambel Kunda in the Central River Region was found to be exceptionally productive with an observed Temminck’s red colobus population of 587 individuals, a maximum group size of 60, and connectivity to robust populations along a riparian corridor to the east. Surveys were supported by the collation of community perceptions using prin- ciples of Rapid Assessment Program (RAP) methodology to evaluate the feasibility of an integrated community development and primate conservation project. The results of interviews and meetings in the Sambel Kunda area revealed an absence of hunting and increasing population trends for all primate species, including red colobus. Excepting the Central River Region, Temminck’s red colobus populations were otherwise in decline or locally extinct, predominantly as a result of indiscriminate hunting to protect agricultural crops. Meetings with the Village Development Committees confirmed that the greatest proximal threat to red colobus in the study area was the rapid escalation in forest clearance to produce charcoal for local markets and timber for export to offset climate-change-induced declines in agricultural revenues. Local Gambians are aware that they urgently need to adopt sustainable forestry practices to mitigate climate change impacts and protect timber and non-timber resources but are currently unsure how they would develop and implement such a model. Given the uncertainty and complex nature of the range-wide threats facing the red colobus populations, we suggest prioritizing the Sambel Kunda area as a site of international importance for the protection and recovery of this Critically Endangered species. A community approach to the conservation of red colobus in the Sambel Kunda area should be implemented without delay through site designation, capacity building for biodiversity monitoring, sustainable for- estry practices, community engagement and education and by growing awareness of Temminck’s red colobus as a flagship species

A time-invariant visco-elastic windkessel model relating blood flow and blood volume

The difference between the rate of change of cerebral blood volume (CBV) and cerebral blood flow (CBF) following stimulation is thought to be due to circumferential stress relaxation in veins (Mandeville, J.B., Marota, J.J.A., Ayata, C., Zaharchuk, G., Moskowitz, M.A., Rosen, B.R., Weisskoff, R.M., 1999. Evidence of a cerebrovascular postarteriole windkessel with delayed compliance. J. Cereb. Blood Flow Metab. 19, 679-689). In this paper we explore the visco-elastic properties of blood vessels, and present a dynamic model relating changes in CBF to changes in CBV. We refer to this model as the visco-elastic windkessel (VW) model. A novel feature of this model is that the parameter characterising the pressure-volume relationship of blood vessels is treated as a state variable dependent oil the rate of change of CBV, producing hysteresis in the pressure-volume space during vessel dilation and contraction. The VW model is nonlinear time-invariant, and is able to predict the observed differences between the time series of CBV and that of CBF measurements following changes in neural activity. Like the windkessel model derived by Mandeville, J.B., Marota, J.J.A., Ayata, C., Zaharchuk, G., Moskowitz, M.A., Rosen, B.R., Weisskoff, R.M., 1999. Evidence of a cerebrovascular postarteriole windkessel with delayed compliance. J. Cereb. Blood Flow Metab. 19, 679-689, the VW model is primarily a model of haemodynamic changes in the venous compartment. The VW model is demonstrated to have the following characteristics typical of visco-elastic materials: (1) hysteresis, (2) creep, and (3) stress relaxation, hence it provides a unified model of the visco-elastic properties of the vasculature. The model will not only contribute to the interpretation of the Blood Oxygen Level Dependent (BOLD) signals from functional Magnetic Resonance Imaging (fMRI) experiments, but also find applications in the study and modelling of the brain vasculature and the haemodynamics of circulatory and cardiovascular systems. (C) 2009 Elsevier Inc. All rights reserved

Targeting anticorruption interventions at the frontline: developmental governance in health systems

In 2008, Vian reported an increasing interest in understanding how corruption affects healthcare outcomes and asked what could be done to combat corruption in the health sector. Eleven years later, corruption is seen as a heterogeneous mix of activity, extensive and expensive in terms of loss of productivity, increasing inequity and costs, but with few examples of programmes that have successfully tackled corruption in low-income or middle-income countries. The commitment, by multilateral organisations and many governments to the Sustainable Development Goals and Universal Health Coverage has renewed an interest to find ways to tackle corruption within health systems. These efforts must, however, begin with a critical assessment of the existing theoretical models and approaches that have underpinned action in the health sector in the past and an assessment of the potential of innovations from anticorruption work developed in sectors other than health. To that end, this paper maps the key debates and theoretical frameworks that have dominated research on corruption in health. It examines their limitations, the blind spots that they create in terms of the questions asked, and the capacity for research to take account of contextual factors that drive practice. It draws on new work from heterodox economics which seeks to target anticorruption interventions at practices that have high impact and which are politically and economically feasible to address. We consider how such approaches can be adopted into health systems and what new questions need to be addressed by researchers to support the development of sustainable solutions to corruption. We present a short case study from Bangladesh to show how such an approach reveals new perspectives on actors and drivers of corruption practice. We conclude by considering the most important areas for research and policy

Development of Graphene Nano-Platelet Ink for High Voltage Flexible Dye Sensitized Solar Cells with Cobalt Complex Electrolytes

Graphene nanoparticles have been subject to intensive investigation as a replacement for platinum as the catalyst in dye sensitized solar cells (DSCs), but few of these investigations examine the application for flexible cells with deposition processes suitable for industrial fabrication. This work introduces a transparent water based graphene ink that can be dried rapidly at less than 110 ºC making it particularly suitable for roll to roll deposition on plastic substrates. This ink has application as a catalyst for dye sensitized solar cells utilizing cobalt complex electrolytes with efficiency of over 6 % and a Voc of 0.89 V at 1 sun demonstrated. A flexible DSC with a printed catalyst and cobalt redox mediator is reported, with efficiency of over 6.0 % and Voc of 0.6 V at 800 lux

The Effect of Communication Change on Long‐term Reductions in Child Exposure to Conflict: Impact of the Promoting Strong African American Families (ProSAAF) Program

African American couples (n = 331) with children, 89% of whom were married, were assigned to either (a) a culturally sensitive couple‐ and parenting‐enhancement program (ProSAAF) or (b) an information‐only control condition in which couples received self‐help materials. Husbands averaged 41 years of age and wives averaged 39 years. We found significant effects of program participation in the short term on couple communication, which was targeted by the intervention, as well as over the long term, on self‐reported arguing in front of children. Long‐term parenting outcomes were fully mediated by changes in communication for wives, but not for husbands. For husbands, positive change depended on amount of wife reported change. We conclude that wives\u27 changes in communication from baseline to posttest may be more pivotal for the couples\u27 long‐term experience of decreased arguing in front of children than are husbands\u27 changes, with wives\u27 changes leading to changes in both partners\u27 reports of arguments in front of children

Dye molecules in electrolytes: new approach for suppression of dye-desorption in dye-sensitized solar cells

The widespread commercialization of dye-sensitized solar cells remains limited because of the poor long-term stability. We report on the influence of dye-molecules added in liquid electrolyte on long-term stability of dye-sensitized solar cells. Dye-desorption from the TiO2 surface during long-term cycling is one of the decisive factors that degrade photocurrent densities of devices which in turn determine the efficiencies of the devices. For the first time, desorption of dye from the TiO2 surface could be suppressed by controlling thermodynamic equilibrium; by addition of dye molecules in the electrolyte. The dye molecules in the electrolyte can suppress the driving forces for the adsorbed dye molecules to be desorbed from TiO2 nanoparticles. As a result, highly enhanced device stabilities were achieved due to the reduction of dye-desorption although there was a little decrease in the initial efficiencies.open4

Motion direction, speed and orientation in binocular matching

The spatial differences between the images seen by the two eyes, called binocular disparities, can be used to recover the volumetric (three-dimensional) aspects of a scene. The computation of disparity depends upon the correct identi®cation of corresponding features in the two images. Understanding what image features are used by the brain to solve this matching problem is one of the main issues in stereoscopic vision. Many cortical neurons in visual areas V1 (ref. 2), MT (refs 3, 4) and MST (refs 5, 6) that are tuned to binocular disparity are also tuned to orientation, motion direction and speed. Although psychophysical work has shown that motion direction can facilitate binocular matching, the psychophysical literature on the role of orientation is mixed^8,9 , and it has been argued that speed differences are ineffective in aiding correspondence^7. Here we use a different psychophysical paradigm to show that the visual system uses similarities in orientation, motion direction and speed to achieve binocular correspondence. These results indicate that cells that multiplex orientation, motion direction, speed and binocular disparity may help to solve the binocular matching problem

Direct nitrogen fixation at the edges of graphene nanoplatelets as efficient electrocatalysts for energy conversion

Nitrogen fixation is essential for the synthesis of many important chemicals (e.g., fertilizers, explosives) and basic building blocks for all forms of life (e.g., nucleotides for DNA and RNA, amino acids for proteins). However, direct nitrogen fixation is challenging as nitrogen (N2) does not easily react with other chemicals. By dry ball-milling graphite with N2, we have discovered a simple, but versatile, scalable and eco-friendly, approach to direct fixation of N2 at the edges of graphene nanoplatelets (GnPs). The mechanochemical cracking of graphitic C-C bonds generated active carbon species that react directly with N2 to form five- and six-membered aromatic rings at the broken edges, leading to solution-processable edge-nitrogenated graphene nanoplatelets (NGnPs) with superb catalytic performance in both dye-sensitized solar cells and fuel cells to replace conventional Pt-based catalysts for energy conversion.open302

Nonhuman primates across sub-Saharan Africa are infected with the yaws bacterium Treponema pallidum subsp. pertenue

Dear Editor, The bacterium Treponema pallidum (TP) causes human syphilis (subsp. pallidum; TPA), bejel (subsp. endemicum; TEN), and yaws (subsp. pertenue; TPE) (1). Although syphilis has reached a worldwide distribution (2), bejel and yaws have remained endemic diseases. Bejel affects individuals in dry areas of Sahelian Africa and Saudi Arabia, whereas yaws affects those living in the humid tropics (1). Yaws is currently reported as endemic in 14 countries, and an additional 84 countries have a known history of yaws but lack recent epidemiological data (3,4). Although this disease was subject to global eradication efforts in the mid-20th century, it later reemerged in West Africa, Southern Asia, and the Pacific region (5). New large-scale treatment options triggered the ongoing second eradication campaign, the goal of which is to eradicate yaws globally by 2020 (5). References: (1) Giacani, L. & Lukehart, S.A. The endemic treponematoses. Clin. Microbiol. Rev. 27, 89–115 (2014). (2) Arora, N. et al. Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster. Nat. Microbiol. 2, 16245 (2016). (3) Marks, M. Yaws: towards the WHO eradication target. Trans. R Soc. Trop. Med. Hyg. 110, 319–320 (2016). (4) World Health Organization. Eradication of yaws: procedures for verification and certification of interruption of transmission (World Health Organization, Geneva, 2018). (5) Asiedu, K., Fitzpatrick, C. & Jannin, J. Eradication of yaws: historical efforts and achieving WHO’s 2020 target. PLoS Negl. Trop. Dis. 8, e3016 (2014)

‘Donor-free’ oligo(3-hexylthiophene) dyes for efficient dye-sensitized solar cells

The common trend in designing dyes for use in DSSCs with iodide-based electrolyte is based on a donor-π spacer-acceptor (D-π-A) architecture. Here, we report two 'donor-free' cyanoacrylic end-functionalized oligo(3-hexylthiophene) dyes (5T and 6T). Despite having no donor group, both dyes show reversible first oxidation process. Both 5T and 6T have n-hexyl alkyl chains to retard aggregation at different positions as well as different numbers of thiophene moieties. However, the dyes showed similar absorption properties and redox potentials. The DSSCs based on these dyes give power conversion efficiencies of more than 7%, although a significant difference in the VOC and FF has been observed. Using electrochemical impedance spectroscopy, this is attributed to the presence of more trap states when 6T attaches to TiO2 and modifies the surface, mainly affecting the fill factor. Overall, these dyes introduce a new and effective design concept for liquid-electrolyte DSSC sensitisers