Redefining Expectations for Place-based Philanthropy

This article discusses how The California Endowment has used a midcourse strategic review to refine Building Healthy Communities, aiming to provide insight for other place-based initiatives and to add to the body of knowledge about how to support transformative community change. With Building Healthy Communities, the endowment is taking a new approach to community change using a dual strategy to build community capacity in 14 places and scale the impact of its local efforts through statewide policy advocacy and communications. In 2013, it commissioned a strategic review to reflect on what it has learned from the first three years of this innovation in place-based work. Through interviews, focus groups, surveys, and document review, examples have emerged of how this unique approach is contributing to community change. The review also surfaced tensions created by the design and implementation of the strategy that could impede progress

Early Vegetation Development on an Exposed Reservoir: Implications for Dam Removal

The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition

Age, extent and carbon storage of the central Congo Basin peatland complex

Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10(15) grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by 36 per cent, to 104.7 petagrams of carbon (minimum estimate of 69.6 petagrams of carbon; maximum estimate of 129.8 petagrams of carbon). This stored carbon is vulnerable to land-use change and any future reduction in precipitation

Environmental heterogeneity has a weak effect on diversity during community assembly in tallgrass prairie

Citation: Baer, S. G., Blair, J. M., & Collins, S. L. (2016). Environmental heterogeneity has a weak effect on diversity during community assembly in tallgrass prairie. Ecological Monographs, 86(1), 94-106. doi:10.1890/15-0888.1Understanding what constrains the persistence of species in communities is at the heart of community assembly theory and its application to conserving and enhancing biodiversity. The "environmental heterogeneity hypothesis" predicts greater species coexistence in habitats with greater resource variability. In the context of community assembly, environmental heterogeneity may influence the variety and strength of abiotic conditions and competitive interactions (environmental filters) to affect the relative abundance of species and biodiversity. We manipulated key resources that influence plant diversity in tallgrass prairie (i.e., soil depth and nitrogen availability) to increase environmental heterogeneity prior to sowing native prairie species into a former agricultural field. We compared variability in nutrient availability, aboveground annual net primary productivity (ANPP), and the composition of species between replicate plots containing soil heterogeneity manipulations and plots with no resource manipulations (n = 4 per treatment) during the first 15 yr of community assembly as a test of the "environmental heterogeneity hypothesis." The manipulations increased environmental heterogeneity, measured as the coefficient of variation in NO3-N availability and ANPP. Plant diversity, however, was similar and decayed exponentially and indiscriminately over time between the heterogeneity treatments. Species richness declined linearly over time in both heterogeneity treatments, but richness was higher in the more heterogeneous soil 2 yr following a second propagule addition 8 yr after the initial sowing. As a result, there was a lower rate of species loss over time in the more heterogeneous soil (0.60 species yr(-1)) relative to the control soil (0.96 species yr(-1)). Communities in each treatment exhibited strong convergence over time resulting from a shift in dominant species across all treatments and a gradual increase in the clonal C-4 grass, Andropogon gerardii. We attribute the weak effect of heterogeneity on diversity to increasing dominance of a clonal species, which decreased the scale of soil treatments relative to plant size, dispersal limitation, and absence of a key driver (grazing) known to increase plant diversity under a frequent fire regime. Thus, steering community assembly to attain high biodiversity may depend more on manipulating processes that reduce dominance and facilitate the arrival of new species than promoting environmental heterogeneity

Phylogeographical analysis of the dominant multidrug-resistant H58 clade of Salmonella Typhi identifies inter- and intracontinental transmission events.

The emergence of multidrug-resistant (MDR) typhoid is a major global health threat affecting many countries where the disease is endemic. Here whole-genome sequence analysis of 1,832 Salmonella enterica serovar Typhi (S. Typhi) identifies a single dominant MDR lineage, H58, that has emerged and spread throughout Asia and Africa over the last 30 years. Our analysis identifies numerous transmissions of H58, including multiple transfers from Asia to Africa and an ongoing, unrecognized MDR epidemic within Africa itself. Notably, our analysis indicates that H58 lineages are displacing antibiotic-sensitive isolates, transforming the global population structure of this pathogen. H58 isolates can harbor a complex MDR element residing either on transmissible IncHI1 plasmids or within multiple chromosomal integration sites. We also identify new mutations that define the H58 lineage. This phylogeographical analysis provides a framework to facilitate global management of MDR typhoid and is applicable to similar MDR lineages emerging in other bacterial species

Distinct Salmonella Enteritidis lineages associated with enterocolitis in high-income settings and invasive disease in low-income settings.

An epidemiological paradox surrounds Salmonella enterica serovar Enteritidis. In high-income settings, it has been responsible for an epidemic of poultry-associated, self-limiting enterocolitis, whereas in sub-Saharan Africa it is a major cause of invasive nontyphoidal Salmonella disease, associated with high case fatality. By whole-genome sequence analysis of 675 isolates of S. Enteritidis from 45 countries, we show the existence of a global epidemic clade and two new clades of S. Enteritidis that are geographically restricted to distinct regions of Africa. The African isolates display genomic degradation, a novel prophage repertoire, and an expanded multidrug resistance plasmid. S. Enteritidis is a further example of a Salmonella serotype that displays niche plasticity, with distinct clades that enable it to become a prominent cause of gastroenteritis in association with the industrial production of eggs and of multidrug-resistant, bloodstream-invasive infection in Africa.This work was supported by the Wellcome Trust. We would like to thank the members of the Pathogen Informatics Team and the core sequencing teams at the Wellcome Trust Sanger Institute (Cambridge, UK). We are grateful to D. Harris for work in managing the sequence data

Incidence of invasive salmonella disease in sub-Saharan Africa: a multicentre population-based surveillance study.

BACKGROUND: Available incidence data for invasive salmonella disease in sub-Saharan Africa are scarce. Standardised, multicountry data are required to better understand the nature and burden of disease in Africa. We aimed to measure the adjusted incidence estimates of typhoid fever and invasive non-typhoidal salmonella (iNTS) disease in sub-Saharan Africa, and the antimicrobial susceptibility profiles of the causative agents. METHODS: We established a systematic, standardised surveillance of blood culture-based febrile illness in 13 African sentinel sites with previous reports of typhoid fever: Burkina Faso (two sites), Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar (two sites), Senegal, South Africa, Sudan, and Tanzania (two sites). We used census data and health-care records to define study catchment areas and populations. Eligible participants were either inpatients or outpatients who resided within the catchment area and presented with tympanic (≥38·0°C) or axillary temperature (≥37·5°C). Inpatients with a reported history of fever for 72 h or longer were excluded. We also implemented a health-care utilisation survey in a sample of households randomly selected from each study area to investigate health-seeking behaviour in cases of self-reported fever lasting less than 3 days. Typhoid fever and iNTS disease incidences were corrected for health-care-seeking behaviour and recruitment. FINDINGS: Between March 1, 2010, and Jan 31, 2014, 135 Salmonella enterica serotype Typhi (S Typhi) and 94 iNTS isolates were cultured from the blood of 13 431 febrile patients. Salmonella spp accounted for 33% or more of all bacterial pathogens at nine sites. The adjusted incidence rate (AIR) of S Typhi per 100 000 person-years of observation ranged from 0 (95% CI 0-0) in Sudan to 383 (274-535) at one site in Burkina Faso; the AIR of iNTS ranged from 0 in Sudan, Ethiopia, Madagascar (Isotry site), and South Africa to 237 (178-316) at the second site in Burkina Faso. The AIR of iNTS and typhoid fever in individuals younger than 15 years old was typically higher than in those aged 15 years or older. Multidrug-resistant S Typhi was isolated in Ghana, Kenya, and Tanzania (both sites combined), and multidrug-resistant iNTS was isolated in Burkina Faso (both sites combined), Ghana, Kenya, and Guinea-Bissau. INTERPRETATION: Typhoid fever and iNTS disease are major causes of invasive bacterial febrile illness in the sampled locations, most commonly affecting children in both low and high population density settings. The development of iNTS vaccines and the introduction of S Typhi conjugate vaccines should be considered for high-incidence settings, such as those identified in this study. FUNDING: Bill & Melinda Gates Foundation

An extended genotyping framework for Salmonella enterica serovar Typhi, the cause of human typhoid.

The population of Salmonella enterica serovar Typhi (S. Typhi), the causative agent of typhoid fever, exhibits limited DNA sequence variation, which complicates efforts to rationally discriminate individual isolates. Here we utilize data from whole-genome sequences (WGS) of nearly 2,000 isolates sourced from over 60 countries to generate a robust genotyping scheme that is phylogenetically informative and compatible with a range of assays. These data show that, with the exception of the rapidly disseminating H58 subclade (now designated genotype 4.3.1), the global S. Typhi population is highly structured and includes dozens of subclades that display geographical restriction. The genotyping approach presented here can be used to interrogate local S. Typhi populations and help identify recent introductions of S. Typhi into new or previously endemic locations, providing information on their likely geographical source. This approach can be used to classify clinical isolates and provides a universal framework for further experimental investigations

Evolution of the life cycle in land plants

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92043/1/j.1759-6831.2012.00188.x.pd

Reformulation of anisotropy corrections in the static dose calculations in high dose rate brachytherapy

Current polynomial methods used in the modelling of the dose distributions in high dose rate (HDR) brachytherapy have been reformulated to improve accuracy. An example is provided in order to assess the errors in some of the conventional methods. We observed relatively high discrepancies between our accurate results and those from some of the standard models, but acknowledge that our algorithm is not very easy to use. We therefore advocate a departure from the polynomial methods of modelling, which are merely empirical and do not reflect the physical processes of the interaction of radiation with tissue. We suggest the use of the parameters like the absorption and attenuation coefficients for the primary and scatter photon beams. With this, we shall have easy - to - use algorithms; doses could be calculated accurately both within and beyond the region of parametrization. Corrections could also be made for finite patient sizes and shapes. JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 2 (2000) pp. 129-13