bluuebunny/crossref_metadata_2025 huggingface dataset:
Single pollinator species losses reduce floral fidelity and plant reproductive function
Authors: Brosi Berry J. , Briggs Heather M.
Published: July 2013

Understanding the functional impacts of pollinator species losses on plant populations is critical given ongoing pollinator declines. Simulation models of pollination networks suggest that plant communities will be resilient to losing many or even most of the pollinator species in an ecosystem. These predictions, however, have not been tested empirically and implicitly assume that pollination efficacy is unaffected by interactions with interspecific competitors. By contrast, ecological theory and data from a wide range of ecosystems show that interspecific competition can drive variation in ecological specialization over short timescales via behavioral or morphological plasticity, although the potential implications of such changes in specialization for ecosystem functioning remain unexplored. We conducted manipulative field experiments in which we temporarily removed single pollinator species from study plots in subalpine meadows, to test the hypothesis that interactions between pollinator species can shape individual species’ functional roles via changes in foraging specialization. We show that loss of a single pollinator species reduces floral fidelity (short-term specialization) in the remaining pollinators, with significant implications for ecosystem functioning in terms of reduced plant reproduction, even when potentially effective pollinators remained in the system. Our results suggest that ongoing pollinator declines may have more serious negative implications for plant communities than is currently assumed. More broadly, we show that the individual functional contributions of species can be dynamic and shaped by the community of interspecific competitors, thereby documenting a distinct mechanism for how biodiversity can drive ecosystem functioning, with potential relevance to a wide range of taxa and systems.
Interphase cytofission maintains genomic integrity of human cells after failed cytokinesis
Authors: Choudhary Alka , Lera Robert F. , Martowicz Melissa L. , Oxendine Kim , Laffin Jennifer J. , Weaver Beth A. , Burkard Mark E.
Published: July 2013

In cell division, cytokinesis is tightly coupled with mitosis to maintain genomic integrity. Failed cytokinesis in humans can result in tetraploid cells that can become aneuploid and promote cancer. However, the likelihood of aneuploidy and cancer after a failed cytokinesis event is unknown. Here we evaluated cell fate after failed cytokinesis. We interrupted cytokinesis by brief chemical treatments in cell populations of human epithelial lines. Surprisingly, up to 50% of the resulting binucleate cells generated colonies. In RPE1 cells, 90% of colonies obtained from binucleate founders had a karyotype that matched the parental cell type. Time-lapse videomicroscopy demonstrated that binucleate cells are delayed in the first growth phase of the cell cycle (G1) and undergo interphase cellular fission (cytofission) that distributes nuclei into separate daughters. The fission is not compatible with delayed cytokinesis because events occur in the absence of polymerized microtubules and without canonical components of the cytokinetic machinery. However, the cytofission can be interrupted by inhibiting function of actin or myosin II. Fission events occur in both two- and three-dimensional culture. Our data demonstrate that cytofission can preserve genomic integrity after failed cytokinesis. Thus, traction-mediated cytofission, originally observed in
Dictyostelium
, is relevant to human biology—where it seems to be an evolutionarily conserved mechanism that can preserve genomic integrity.
Rapid and robust signaling in the CsrA cascade via RNA–protein interactions and feedback regulation
Authors: Adamson David Nellinger , Lim Han N.
Published: July 2013

Bacterial survival requires the rapid propagation of signals through gene networks during stress, but how this is achieved is not well understood. This study systematically characterizes the signaling dynamics of a cascade of RNA–protein interactions in the CsrA system, which regulates stress responses and biofilm formation in
Escherichia coli
. Noncoding RNAs are at the center of the CsrA system; target mRNAs are bound by CsrA proteins that inhibit their translation, CsrA proteins are sequestered by CsrB noncoding RNAs, and the degradation of CsrB RNAs is increased by CsrD proteins. Here, we show using in vivo experiments and quantitative modeling that the CsrA system integrates three strategies to achieve rapid and robust signaling. These strategies include: (
i
) the sequestration of stable proteins by noncoding RNAs, which rapidly inactivates protein activity; (
ii
) the degradation of stable noncoding RNAs, which enables their rapid removal; and (
iii
) a negative-feedback loop created by CsrA repression of CsrD production, which reduces the time for the system to achieve steady state. We also demonstrate that sequestration in the CsrA system results in signaling that is robust to growth rates because it does not rely on the slow dilution of molecules via cell division; therefore, signaling can occur even during growth arrest induced by starvation or antibiotic treatment.
Dietary gluten triggers concomitant activation of CD4
+
and CD8
+
αβ T cells and γδ T cells in celiac disease
Authors: Han Arnold , Newell Evan W. , Glanville Jacob , Fernandez-Becker Nielsen , Khosla Chaitan , Chien Yueh-hsiu , Davis Mark M.
Published: July 2013

Celiac disease is an intestinal autoimmune disease driven by dietary gluten and gluten-specific CD4
+
T-cell responses. In celiac patients on a gluten-free diet, exposure to gluten induces the appearance of gluten-specific CD4
+
T cells with gut-homing potential in the peripheral blood. Here we show that gluten exposure also induces the appearance of activated, gut-homing CD8
+
αβ and γδ T cells in the peripheral blood. Single-cell T-cell receptor sequence analysis indicates that both of these cell populations have highly focused T-cell receptor repertoires, indicating that their induction is antigen-driven. These results reveal a previously unappreciated role of antigen in the induction of CD8
+
αβ and γδ T cells in celiac disease and demonstrate a coordinated response by all three of the major types of T cells. More broadly, these responses may parallel adaptive immune responses to viral pathogens and other systemic autoimmune diseases.
Ion channel-kinase TRPM
7
is required for maintaining cardiac automaticity
Authors: Sah Rajan , Mesirca Pietro , Van den Boogert Marjolein , Rosen Jonathan , Mably John , Mangoni Matteo E. , Clapham David E.
Published: July 2013

Significance

T
ransient
R
eceptor
P
otential
M
elastatin
7
(TRPM7) is a divalent-permeant channel-kinase of unknown function expressed in human atrial myocytes and fibroblasts and recently implicated in atrial arrhythmias. We show that TRPM7 is highly expressed in embryonic myocardium and sinoatrial node (SAN).
Trpm7
disruption in vitro, in cultured embryonic cardiomyocytes, and in vivo in zebrafish and in mice impairs cardiac automaticity. We show that this occurs via reductions in
Hcn4
mRNA and the pacemaker current,
I

f

, in SAN. We conclude that TRPM7 influences diastolic membrane depolarization and automaticity in SAN via regulation of
Hcn4
expression.
Sequence organization and timing of bonobo mother-infant interactions
Authors: Rossano Federico
Published: July 2013

In recent years, some scholars have claimed that humans are unique in their capacity and motivation to engage in cooperative communication and extensive, fast-paced social interactions. While research on gestural communication in great apes has offered important findings concerning the gestural repertoires of different species, very little is known about the sequential organization of primates’ communicative behavior during interactions. Drawing on a conversation analytic framework, this paper addresses this gap by investigating the sequential organization of bonobo mother-infant interactions, and more specifically, how individuals solicit carries from one another. It shows how bonobos establish participation frameworks before producing a carry request gesture and how the ensuing communicative actions can be organized in adjacency-pair sequences. Moreover, the timing between the initiation of an action and its response is similar to what has been documented in adult human interaction. Finally, it outlines some of the orderly practices bonobos use to deal with the absence of response from the addressed participants in carry sequences. Keywords: adjacency pair; pan paniscus; conversation analysis; gestures; interactional time; sequence organization
Mutual adaptation in parent-child interaction
Authors: Forrester Michael A.
Published: July 2013

During the early years a young child gradually becomes a member of a culture by learning how to understand and then produce relevant social practices – particularly through interaction in conversation. This paper examines how one child adapts to the practices surrounding the production of questions and answers. Adopting a longitudinal case-study approach and employing conversation analysis, consideration is given to the question-answer practices this child produces during asymmetric conversations across the period when she is acquiring conversational skills (from 12 months to 3 years 7 months). Through a micro-analytic examination of extract examples across this period, it becomes clear that although initially a child can learn the format of question-answer sequences, it is not until the third year that some recognition of being accountable for the form of an answer becomes evident. Between the ages of 2 and 3, we observe that this child is called to account for answers that are deemed inappropriate or odd. Concluding comments consider these practices as forms of social adaptation within asymmetric interactive contexts. Keywords: child-parent-interaction; asymmetric interaction; learning conversational skills
CD28-inducible transcription factor DEC1 is required for efficient autoreactive CD4+ T cell response
Authors: Martínez-Llordella Marc , Esensten Jonathan H. , Bailey-Bucktrout Samantha L. , Lipsky Robert H. , Marini Ann , Chen Jun , Mughal Mohamed , Mattson Mark P. , Taub Dennis D. , Bluestone Jeffrey A.
Published: July 2013

During the initial hours after activation, CD4+ T cells experience profound changes in gene expression. Co-stimulation via the CD28 receptor is required for efficient activation of naive T cells. However, the transcriptional consequences of CD28 co-stimulation are not completely understood. We performed expression microarray analysis to elucidate the effects of CD28 signals on the transcriptome of activated T cells. We show that the transcription factor DEC1 is highly induced in a CD28-dependent manner upon T cell activation, is involved in essential CD4+ effector T cell functions, and participates in the transcriptional regulation of several T cell activation pathways, including a large group of CD28-regulated genes. Antigen-specific, DEC1-deficient CD4+ T cells have cell-intrinsic defects in survival and proliferation. Furthermore, we found that DEC1 is required for the development of experimental autoimmune encephalomyelitis because of its critical role in the production of the proinflammatory cytokines GM-CSF, IFN-γ, and IL-2. Thus, we identify DEC1 as a critical transcriptional mediator in the activation of naive CD4+ T cells that is required for the development of a T cell–mediated autoimmune disease.
Executive Summary: A Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2013 Recommendations by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM)a
Authors: Baron Ellen Jo , Miller J. Michael , Weinstein Melvin P. , Richter Sandra S. , Gilligan Peter H. , Thomson Richard B. , Bourbeau Paul , Carroll Karen C. , Kehl Sue C. , Dunne W. Michael , Robinson-Dunn Barbara , Schwartzman Joseph D. , Chapin Kimberle C. , Snyder James W. , Forbes Betty A. , Patel Robin , Rosenblatt Jon E. , Pritt Bobbi S.
Published: July 2013

The critical role of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. This document, developed by both laboratory and clinical experts, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. Sections are divided into anatomic systems, including Bloodstream Infections and Infections of the Cardiovascular System, Central Nervous System Infections, Ocular Infections, Soft Tissue Infections of the Head and Neck, Upper Respiratory Infections, Lower Respiratory Tract infections, Infections of the Gastrointestinal Tract, Intraabdominal Infections, Bone and Joint Infections, Urinary Tract Infections, Genital Infections, and Skin and Soft Tissue Infections; or into etiologic agent groups, including Tickborne Infections, Viral Syndromes, and Blood and Tissue Parasite Infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. There is redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a reference to guide physicians in choosing tests that will aid them to diagnose infectious diseases in their patients.
The far emission region of the γ-ray blazar PKS B1424–418
Authors: Tavecchio F. , Pacciani L. , Donnarumma I. , Stamerra A. , Isler J. , MacPherson E. , Urry C. M.
Published: July 2013

We report multiwavelength (infrared–optical, ultraviolet, X-ray and γ-ray) data from the flat spectrum radio quasar (FSRQ) PKS B1424−418 (z = 1.52) gathered during an active phase in 2013 April. As for a few other cases of FSRQs reported in literature, the detection by the Large Area Telescope on board Fermi of γ-rays with energy above 10 GeV indicates that the emission likely occurs beyond the highly opaque (τ ∼ 10) broad-line region. This conclusion is strengthened by a model fit to the spectral energy distribution, which allows us to locate the emission region even beyond the distance generally assumed for the dusty torus. The consequent large size (∼1 pc) inferred for the emission region cannot account for the observed daily-scale variability of the γ-ray flux. We discuss the possibility that short-term variability results from fast magnetic reconnection events, as proposed in recent works.
Above-ground biomass and structure of 260 African tropical forests
Authors: Lewis Simon L. , Sonké Bonaventure , Sunderland Terry , Begne Serge K. , Lopez-Gonzalez Gabriela , van der Heijden Geertje M. F. , Phillips Oliver L. , Affum-Baffoe Kofi , Baker Timothy R. , Banin Lindsay , Bastin Jean-François , Beeckman Hans , Boeckx Pascal , Bogaert Jan , De Cannière Charles , Chezeaux Eric , Clark Connie J. , Collins Murray , Djagbletey Gloria , Djuikouo Marie Noël K. , Droissart Vincent , Doucet Jean-Louis , Ewango Cornielle E. N. , Fauset Sophie , Feldpausch Ted R. , Foli Ernest G. , Gillet Jean-François , Hamilton Alan C. , Harris David J. , Hart Terese B. , de Haulleville Thales , Hladik Annette , Hufkens Koen , Huygens Dries , Jeanmart Philippe , Jeffery Kathryn J. , Kearsley Elizabeth , Leal Miguel E. , Lloyd Jon , Lovett Jon C. , Makana Jean-Remy , Malhi Yadvinder , Marshall Andrew R. , Ojo Lucas , Peh Kelvin S.-H. , Pickavance Georgia , Poulsen John R. , Reitsma Jan M. , Sheil Douglas , Simo Murielle , Steppe Kathy , Taedoumg Hermann E. , Talbot Joey , Taplin James R. D. , Taylor David , Thomas Sean C. , Toirambe Benjamin , Verbeeck Hans , Vleminckx Jason , White Lee J. T. , Willcock Simon , Woell Hannsjorg , Zemagho Lise
Published: July 2013

We report above-ground biomass (AGB), basal area, stem density and wood mass density estimates from 260 sample plots (mean size: 1.2 ha) in intact closed-canopy tropical forests across 12 African countries. Mean AGB is 395.7 Mg dry mass ha
−1
(95% CI: 14.3), substantially higher than Amazonian values, with the Congo Basin and contiguous forest region attaining AGB values (429 Mg ha
−1
) similar to those of Bornean forests, and significantly greater than East or West African forests. AGB therefore appears generally higher in palaeo- compared with neotropical forests. However, mean stem density is low (426 ± 11 stems ha
−1
greater than or equal to 100 mm diameter) compared with both Amazonian and Bornean forests (cf. approx. 600) and is the signature structural feature of African tropical forests. While spatial autocorrelation complicates analyses, AGB shows a positive relationship with rainfall in the driest nine months of the year, and an opposite association with the wettest three months of the year; a negative relationship with temperature; positive relationship with clay-rich soils; and negative relationships with C : N ratio (suggesting a positive soil phosphorus–AGB relationship), and soil fertility computed as the sum of base cations. The results indicate that AGB is mediated by both climate and soils, and suggest that the AGB of African closed-canopy tropical forests may be particularly sensitive to future precipitation and temperature changes.
Congo Basin rainfall climatology: can we believe the climate models?
Authors: Washington Richard , James Rachel , Pearce Helen , Pokam Wilfried M. , Moufouma-Okia Wilfran
Published: July 2013

The Congo Basin is one of three key convective regions on the planet which, during the transition seasons, dominates global tropical rainfall. There is little agreement as to the distribution and quantity of rainfall across the basin with datasets differing by an order of magnitude in some seasons. The location of maximum rainfall is in the far eastern sector of the basin in some datasets but the far western edge of the basin in others during March to May. There is no consistent pattern to this rainfall distribution in satellite or model datasets. Resolving these differences is difficult without ground-based data. Moisture flux nevertheless emerges as a useful variable with which to study these differences. Climate models with weak (strong) or even divergent moisture flux over the basin are dry (wet). The paper suggests an approach, via a targeted field campaign, for generating useful climate information with which to confront rainfall products and climate models.
Implications of global warming for the climate of African rainforests
Authors: James Rachel , Washington Richard , Rowell David P.
Published: July 2013

African rainforests are likely to be vulnerable to changes in temperature and precipitation, yet there has been relatively little research to suggest how the regional climate might respond to global warming. This study presents projections of temperature and precipitation indices of relevance to African rainforests, using global climate model experiments to identify local change as a function of global temperature increase. A multi-model ensemble and two perturbed physics ensembles are used, one with over 100 members. In the east of the Congo Basin, most models (92%) show a wet signal, whereas in west equatorial Africa, the majority (73%) project an increase in dry season water deficits. This drying is amplified as global temperature increases, and in over half of coupled models by greater than 3% per °C of global warming. Analysis of atmospheric dynamics in a subset of models suggests that this could be partly because of a rearrangement of zonal circulation, with enhanced convection in the Indian Ocean and anomalous subsidence over west equatorial Africa, the Atlantic Ocean and, in some seasons, the Amazon Basin. Further research to assess the plausibility of this and other mechanisms is important, given the potential implications of drying in these rainforest regions.
State and evolution of the African rainforests between 1990 and 2010
Authors: Mayaux Philippe , Pekel Jean-François , Desclée Baudouin , Donnay François , Lupi Andrea , Achard Frédéric , Clerici Marco , Bodart Catherine , Brink Andreas , Nasi Robert , Belward Alan
Published: July 2013

This paper presents a map of Africa's rainforests for 2005. Derived from moderate resolution imaging spectroradiometer data at a spatial resolution of 250 m and with an overall accuracy of 84%, this map provides new levels of spatial and thematic detail. The map is accompanied by measurements of deforestation between 1990, 2000 and 2010 for West Africa, Central Africa and Madagascar derived from a systematic sample of Landsat images—imagery from equivalent platforms is used to fill gaps in the Landsat record. Net deforestation is estimated at 0.28% yr
−1
for the period 1990–2000 and 0.14% yr
−1
for the period 2000–2010. West Africa and Madagascar exhibit a much higher deforestation rate than the Congo Basin, for example, three times higher for West Africa and nine times higher for Madagascar. Analysis of variance over the Congo Basin is then used to show that expanding agriculture and increasing fuelwood demands are key drivers of deforestation in the region, whereas well-controlled timber exploitation programmes have little or no direct influence on forest-cover reduction at present. Rural and urban population concentrations and fluxes are also identified as strong underlying causes of deforestation in this study.
Tropical forest recovery from logging: a 24 year silvicultural experiment from Central Africa
Authors: Gourlet-Fleury Sylvie , Mortier Frédéric , Fayolle Adeline , Baya Fidèle , Ouédraogo Dakis , Bénédet Fabrice , Picard Nicolas
Published: July 2013

Large areas of African moist forests are being logged in the context of supposedly sustainable management plans. It remains however controversial whether harvesting a few trees per hectare can be maintained in the long term while preserving other forest services as well. We used a unique 24 year silvicultural experiment, encompassing 10 4 ha plots established in the Central African Republic, to assess the effect of disturbance linked to logging (two to nine trees ha−1greater than or equal to 80 cm DBH) and thinning (11–41 trees ha−1greater than or equal to 50 cm DBH) on the structure and dynamics of the forest. Before silvicultural treatments, above-ground biomass (AGB) and timber stock (i.e. the volume of commercial trees greater than or equal to 80 cm DBH) in the plots amounted 374.5 ± 58.2 Mg ha−1and 79.7 ± 45.9 m3ha−1, respectively. We found that (i) natural control forest was increasing in AGB (2.58 ± 1.73 Mg dry mass ha−1yr−1) and decreasing in timber stock (−0.33 ± 1.57 m3ha−1yr−1); (ii) the AGB recovered very quickly after logging and thinning, at a rate proportional to the disturbance intensity (mean recovery after 24 years: 144%). Compared with controls, the gain almost doubled in the logged plots (4.82 ± 1.22 Mg ha−1yr−1) and tripled in the logged + thinned plots (8.03 ± 1.41 Mg ha−1yr−1); (iii) the timber stock recovered slowly (mean recovery after 24 years: 41%), at a rate of 0.75 ± 0.51 m3ha−1yr−1in the logged plots, and 0.81 ± 0.74 m3ha−1yr−1in the logged + thinned plots. Although thinning significantly increased the gain in biomass, it had no effect on the gain in timber stock. However, thinning did foster the growth and survival of small- and medium-sized timber trees and should have a positive effect over the next felling cycle.
Extent and ecological consequences of hunting in Central African rainforests in the twenty-first century
Authors: Abernethy K. A. , Coad L. , Taylor G. , Lee M. E. , Maisels F.
Published: July 2013

Humans have hunted wildlife in Central Africa for millennia. Today, however, many species are being rapidly extirpated and sanctuaries for wildlife are dwindling. Almost all Central Africa's forests are now accessible to hunters. Drastic declines of large mammals have been caused in the past 20 years by the commercial trade for meat or ivory. We review a growing body of empirical data which shows that trophic webs are significantly disrupted in the region, with knock-on effects for other ecological functions, including seed dispersal and forest regeneration. Plausible scenarios for land-use change indicate that increasing extraction pressure on Central African forests is likely to usher in new worker populations and to intensify the hunting impacts and trophic cascade disruption already in progress, unless serious efforts are made for hunting regulation. The profound ecological changes initiated by hunting will not mitigate and may even exacerbate the predicted effects of climate change for the region. We hypothesize that, in the near future, the trophic changes brought about by hunting will have a larger and more rapid impact on Central African rainforest structure and function than the direct impacts of climate change on the vegetation. Immediate hunting regulation is vital for the survival of the Central African rainforest ecosystem.
Vegetation structure and greenness in Central Africa from Modis multi-temporal data
Authors: Gond Valéry , Fayolle Adeline , Pennec Alexandre , Cornu Guillaume , Mayaux Philippe , Camberlin Pierre , Doumenge Charles , Fauvet Nicolas , Gourlet-Fleury Sylvie
Published: July 2013

African forests within the Congo Basin are generally mapped at a regional scale as broad-leaved evergreen forests, with the main distinction being between terra-firme and swamp forest types. At the same time, commercial forest inventories, as well as national maps, have highlighted a strong spatial heterogeneity of forest types. A detailed vegetation map generated using consistent methods is needed to inform decision makers about spatial forest organization and their relationships with environmental drivers in the context of global change. We propose a multi-temporal remotely sensed data approach to characterize vegetation types using vegetation index annual profiles. The classifications identified 22 vegetation types (six savannas, two swamp forests, 14 forest types) improving existing vegetation maps. Among forest types, we showed strong variations in stand structure and deciduousness, identifying (i) two blocks of dense evergreen forests located in the western part of the study area and in the central part on sandy soils; (ii) semi-deciduous forests are located in the Sangha River interval which has experienced past fragmentation and human activities. For all vegetation types enhanced vegetation index profiles were highly seasonal and strongly correlated to rainfall and to a lesser extent, to light regimes. These results are of importance to predict spatial variations of carbon stocks and fluxes, because evergreen/deciduous forests (i) have contrasted annual dynamics of photosynthetic activity and foliar water content and (ii) differ in community dynamics and ecosystem processes.
African rainforests: past, present and future
Authors: Malhi Yadvinder , Adu-Bredu Stephen , Asare Rebecca A. , Lewis Simon L. , Mayaux Philippe
Published: July 2013

The rainforests are the great green heart of Africa, and present a unique combination of ecological, climatic and human interactions. In this synthesis paper, we review the past and present state processes of change in African rainforests, and explore the challenges and opportunities for maintaining a viable future for these biomes. We draw in particular on the insights and new analyses emerging from the Theme Issue on ‘African rainforests: past, present and future’ of
Philosophical Transactions of the Royal Society B
. A combination of features characterize the African rainforest biome, including a history of climate variation; forest expansion and retreat; a long history of human interaction with the biome; a relatively low plant species diversity but large tree biomass; a historically exceptionally high animal biomass that is now being severely hunted down; the dominance of selective logging; small-scale farming and bushmeat hunting as the major forms of direct human pressure; and, in Central Africa, the particular context of mineral- and oil-driven economies that have resulted in unusually low rates of deforestation and agricultural activity. We conclude by discussing how this combination of factors influences the prospects for African forests in the twenty-first century.
Woody encroachment and forest degradation in sub-Saharan Africa's woodlands and savannas 1982–2006
Authors: Mitchard Edward T. A. , Flintrop Clara M.
Published: July 2013

We review the literature and find 16 studies from across Africa's savannas and woodlands where woody encroachment dominates. These small-scale studies are supplemented by an analysis of long-term continent-wide satellite data, specifically the Normalized Difference Vegetation Index (NDVI) time series from the Global Inventory Modeling and Mapping Studies (GIMMS) dataset. Using dry-season data to separate the tree and grass signals, we find 4.0% of non-rainforest woody vegetation in sub-Saharan Africa (excluding West Africa) significantly increased in NDVI from 1982 to 2006, whereas 3.52% decreased. The increases in NDVI were found predominantly to the north of the Congo Basin, with decreases concentrated in the Miombo woodland belt. We hypothesize that areas of increasing dry-season NDVI are undergoing woody encroachment, but the coarse resolution of the study and uncertain relationship between NDVI and woody cover mean that the results should be interpreted with caution; certainly, these results do not contradict studies finding widespread deforestation throughout the continent. However, woody encroachment could be widespread, and warrants further investigation as it has important consequences for the global carbon cycle and land–climate interactions.
Cryptogein-Induced Transcriptional Reprogramming in Tobacco Is Light Dependent
Authors: Hoeberichts Frank A. , Davoine Céline , Vandorpe Michaël , Morsa Stijn , Ksas Brigitte , Stassen Catherine , Triantaphylidès Christian , Van Breusegem Frank
Published: July 2013

The fungal elicitor cryptogein triggers a light-dependent hypersensitive response in tobacco (Nicotiana tabacum). To assess the effect of light on this nonhost resistance in more detail, we studied various aspects of the response under dark and light conditions using the tobacco-cryptogein experimental system. Here, we show that light drastically alters the plant’s transcriptional response to cryptogein, notably by dampening the induction of genes involved in multiple processes, such as ethylene biosynthesis, secondary metabolism, and glutathione turnover. Furthermore, chlorophyll fluorescence measurements demonstrated that quantum yield and functioning of the light-harvesting antennae decreased simultaneously, indicating that photoinhibition underlies the observed decreased photosynthesis and that photooxidative damage might be involved in the establishment of the altered response. Analysis of the isomer distribution of hydroxy fatty acids illustrated that, in the light, lipid peroxidation was predominantly due to the production of singlet oxygen. Differences in (reduced) glutathione concentrations and the rapid development of symptoms in the light when cryptogein was coinfiltrated with glutathione biosynthesis inhibitors suggest that glutathione might become a limiting factor during the cryptogein-induced hypersensitive response in the dark and that this response might be modified by an increased antioxidant availability in the light.
Periodically structured X-ray waveguides
Authors: Bukreeva Inna , Sorrentino Andrea , Cedola Alessia , Giovine Ennio , Diaz Ana , Scarinci Fernando , Jark Werner , Ognev Leonid , Lagomarsino Stefano
Published: July 2013

The properties of X-ray vacuum-gap waveguides (WGs) with additional periodic structure on one of the reflecting walls are studied. Theoretical considerations, numerical simulations and experimental results confirm that the periodic structure imposes additional conditions on efficient propagation of the electromagnetic field along the WGs. The transmission is maximum for guided modes that possess sufficient phase synchronism with the periodic structure (here called `super-resonances'). The field inside the WGs is essentially given at low incidence angle by the fundamental mode strongly coupled with the corresponding phased-matched mode. Both the simulated and the experimental diffraction patterns show in the far field that propagation takes place essentially only for low incidence angles, confirming the mode filtering properties of the structured X-ray waveguides.
Anandamide modulates the neuroendocrine responses induced by extracellular volume expansion
Authors: Ruginsk Silvia G , Uchoa Ernane T , Elias Lucila LK , Antunes‐Rodrigues Jose
Published: July 2013

The aim of the present study was to evaluate the effects of intracerebroventricular administration of anandamide (AEA), an inhibitor of fatty acid amide hydrolase activity (URB597) and a CB1 receptor (CB1R) antagonist (AM251) on the homeostatic responses elicited by extracellular volume expansion (EVE) in male adult rats.

Pretreatment with AEA (100 ng/4 μL) significantly reduced the effect of hypertonic (H‐) EVE on plasma concentrations of prolactin (PRL), oxytocin (OT) and corticosterone, but not vasopressin (AVP). Administration of URB597 (20 μg/5 μL) alone significantly reduced PRL, OT, AVP and corticosterone in the H‐EVE group. Conversely, URB597 and AEA had no significant effect on basal hormone concentrations. Pretreatment with AM251 (200 ng/2 μL) potentiated OT but did not change AVP plasma levels in the H‐EVE group.

Hypertonic EVE significantly increased AVP and OT mRNA expression in the supraoptic nucleus (SON), an effect that was blunted in AEA‐pretreated rats. Pretreatment with AEA did not change the percentage of vasopressinergic or oxytocinergic neurons colocalizing c‐Fos in the SON, but increased nitrate concentrations in the median eminence of animals subjected to H‐EVE.

The present data suggest that: (i) vasopressinergic and oxytocinergic neurons may be differentially affected by AEA; (ii) activation of CB1R may restrain the response of the neurohypophyseal system (NHS) to EVE; (iii) the hypothalamic–pituitary–adrenal axis, PRL and the NHS may still be sensitive to AEA after EVE, with these effects probably not dependent on AEA metabolism; and (iv) AEA and nitric oxide could interact in vivo as modulators to directly control stress‐induced responses.
Infections and inflammatory bowel disease: Challenges in Asia
Authors: Ng Siew C , Chan Francis KL
Published: July 2013

The diagnosis and management of inflammatory bowel disease (IBD) in Asia can be challenging as certain infections can mimic IBD and lead to a misdiagnosis. Colitis can be caused by bacterial infections, ileitis can result from Yersinia and Salmonella infections and ileocolonic ulcers can be seen in intestinal tuberculosis and amebiasis. In addition, cytomegalovirus and Clostridium difficile infection may mimic a flare of IBD and their presence is associated with an increased risk of colectomy and mortality. Because of the increasing use of corticosteroids, immunosuppressive drugs and biological agents the risk of opportunistic infection and the reactivation of latent infection including tuberculosis and hepatitis B, are also higher in IBD patients. Screening and prevention of infection, timely vaccination and the education of the patient is paramount before initiating immunosuppressive drugs. The role of the physician lies not only in the diagnosis and management of IBD but also in the ability to prevent, recognize and treat infections.
Genomic Resources Notes accepted 1 April 2013–31 May 2013
Authors:   Genomic Resources Development Consortium, Coltman David W. , Hogg John T. , Miller Joshua M.
Published: July 2013

This article documents the public availability of approximately 15 000 polymorphic SNP loci for the bighorn sheep Ovis canadensis.
High‐resolution DNA melt‐curve analysis for cost‐effective mass screening of pairwise species interactions
Authors: McCarthy James K. , Didham Raphael K. , Brockerhoff Eckehard G. , van Bysterveldt Katherine A. , Varsani Arvind
Published: July 2013

Ecological studies of pairwise interactions are constrained by the methods available for rapid species identification of the interacting organisms. The resolution of data required to characterize species interaction networks at multiple spatio‐temporal scales can be intensive, and therefore laborious and costly to collect. We explore the utility of high‐resolution DNA melt‐curve analysis (HRM) as a rapid species identification method. An approach was developed to identify organisms at the pairwise interaction level, with particular application to cryptic species interactions that are traditionally difficult to study. Here, we selected a challenging application; to identify the presence/absence of pathogenic fungi (Sporothrix inflata, Ophiostoma nigrocarpum and Ophiostoma galeiforme) transported by bark beetle vectors (Hylastes ater and Hylurgus ligniperda). The technique was able to distinguish between different species of DNA within a single, pooled sample. In test applications, HRM was effective in the mass screening and identification of pathogenic fungal species carried by many individual bark beetle vectors (n = 455 beetles screened) across large geographic scales. For two of the fungal species, there was no difference in the frequency of association with either of their vectors, but for the third fungal species there was a shift in vector–pathogen associations across locations. This technique allows rapid, mass screening and characterization of species interactions at a fraction of the time and cost of traditional methods. It is anticipated that this method can be readily applied to explore other cryptic species interactions, or other studies requiring rapid generation of large data sets and/or high‐throughput efficiency.
Genetic assessment of safflower (Carthamus tinctorius L.) collection with microsatellite markers acquired via pyrosequencing method
Authors: Lee Gi‐An , Sung Jung‐Sook , Lee Sok‐Young , Chung Jong‐Wook , Yi Jung‐Yoon , Kim Yeon‐Gyu , Lee Myung‐Chul
Published: July 2013

A genetic evaluation of safflower germplasm collections derived from different geographical regions and countries will provide useful information for sustainable conservation and the utilization of genetic diversity. However, the molecular marker information is limited for evaluation of genetic diversity of safflower germplasm. In this study, we acquired 509 putative genomic SSR markers for sufficient genome coverage using next‐generation sequencing methods and characterized thirty polymorphic SSRs in safflower collection composed of 100 diverse accessions. The average allele number and expected heterozygosity were 2.8 and 0.386, respectively. Analysis of population structure and phylogeny based on thirty SSR profiles revealed genetic admixture between geographical regions contrary to genetic clustering. However, the accessions from Korea were genetically conserved in distinctive groups in contrast to other safflower gene pool. In conclusion, these new genomic SSRs will facilitate valuable studies to clarify genetic relationships as well as conduct population structure analyses, genetic map construction and association analysis for safflower.
Bovine Model of Chronic Ischemic Cardiomyopathy: Implications for Ventricular Assist Device Research
Authors: Bartoli Carlo R. , Sherwood Leslie C. , Giridharan Guruprasad A. , Slaughter Mark S. , Wead William B. , Prabhu Sumanth D. , Koenig Steven C.
Published: July 2013

Ventricular assist devices (VADs) have emerged as a successful treatment option for advanced heart failure. The objective of this study was to develop a clinically relevant model of chronic ischemic cardiomyopathy to investigate functional, histological, and molecular changes during mechanical circulatory support. In calves (n = 17, 94 ± 7 kg), 90 μm microspheres were injected percutaneously into the left coronary artery. Serial echocardiography was performed weekly to evaluate cardiac function. Sixty days after coronary microembolization, a terminal study was performed via thoracotomy to measure hemodynamics. Regional myocardial and end‐organ blood flows were quantified with 15‐μm fluorescent‐labeled microspheres. Myocardial fibrosis, myocyte size, and myocardial apoptosis were quantified with histological stains. Eleven animals survived coronary microembolization and exhibited clinical and statistically significant echocardiographic and hemodynamic signs of severe systolic dysfunction. Statistically significant decreases in regional myocardial blood flow and increases in myocardial fibrosis, myocyte size, total myocardial apoptosis, and cardiac myocyte‐specific apoptosis were observed. End‐organ hypoperfusion was observed. Coronary microembolization induced stable and reproducible chronic left ventricular failure in calves. The anatomical size and physiology of the bovine heart and thorax are appropriate to study novel interventions for the clinical management of heart failure. This model is an appropriate physiological substrate in which to test VAD and adjunctive biological therapies.
Design for a Lithographically Patterned Bioartificial Endocrine Pancreas
Authors: Park Jaehyun , Kalinin Yevgeniy V. , Kadam Sachin , Randall Christina L. , Gracias David H.
Published: July 2013

Cell encapsulation provides a means to transplant therapeutic cells for a variety of diseases including diabetes. However, due to the large numbers of cells, approximately on the order of a billion, that need to be transplanted for human diabetes therapy, adequate mass transport of nutrients such as oxygen presents a major challenge. Proof‐of‐concept for the design of a bioartificial endocrine pancreas (BAEP) that is optimized to minimize hypoxia in a scalable and precise architecture is demonstrated using a combination of simulations and experiments. The BAEP is composed of an array of porous, lithographically patterned polyhedral capsules arrayed on a rolled‐up alginate sheet. All the important structural variables such as the capsule dimensions, pore characteristics, and spacing can be precisely engineered and tuned. Further, all cells are encapsulated within a single device with a volume not much greater than the total volume of the encapsulated cells, and no cell within the device is located more than 200 μm from the surrounding medium that facilitates efficient mass transport with the surroundings. Compared with gel‐based encapsulation methods, our approach offers unprecedented precision and tunability of structural parameters as well as the volume of the encapsulated cells and consequently the amount of secreted insulin. Our work highlights the utility of lithography and self‐assembly in the fabrication of micro‐ and nanostructured three‐dimensional structures that simulate the function of natural endocrine organs.
Insurance and sustainability in flood‐risk management: the UK in a transitional state
Authors: Ball Tom , Werritty Alan , Geddes Alistair
Published: July 2013

The emerging new paradigm of ‘sustainable flood‐risk management’, emphasising non‐structural management approaches over engineered defences, is subject to differing, and sometimes contested, interpretations by key actors. This is well illustrated by the present lack of agreement between the UK government and the private insurance sector on the future of flood insurance. This paper examines the diversity of views on how best to manage flood risk, given projected changes in the UK insurance market. The issues examined comprise: the linkage of flood defences to the insurability of properties at risk, possible implications of partial or full removal of cross‐subsidisation of policies, and the sustainability of communities in high flood‐risk areas. Finally, the paper looks critically at alternative models that might be applied in the future, based on international experience, which may offer a means of securing insurance for high flood‐risk areas, while also being compatible with sustainable flood‐risk management policies.
The Lehman Minibonds crisis and financialisation of investor subjects in Singapore
Authors: Lai Karen P Y
Published: July 2013

Using the case of the Lehman Minibonds crisis in Singapore, this paper aims to elucidate processes of financialisation and geographies of investor subjects by investigating the reshaping of retail banking consumers into investor subjects. Instead of painting all investor subjects with a broad brush as part of a generic financialisation process, the Minibonds crisis demonstrates how the consumption of financial products is geographically specific and moderated by local factors, such that financial subjects are incorporated unevenly into global financial markets. Greater geographical sensitivity is therefore needed to tease out how distinctive groupings or ecologies of financial knowledge, practices and subjectivities emerge in different places with uneven connectivity and unequal material outcomes. The paper concludes by discussing the incomplete and contingent nature of subject formation and implications for understanding neoliberal subjectivities.
Excess mortality during hospital stays among patients with recorded diabetes compared with those without diabetes
Authors: Holman N. , Hillson R. , Young R. J.
Published: July 2013

Aim

To assess the additional mortality during hospital admissions among patients with recorded diabetes and identify the extent of variation in English provider trusts.

Methods

Inpatient admissions to all English hospitals between April 2010 and March 2012 were extracted from Hospital Episode Statistics. Binary logistic regression was used to standardize for age, sex, deprivation, method and reason for admission, co‐morbidities and type of trust. Trust level standardized mortality ratios for inpatients with recorded diabetes were compared with those without recorded diabetes and with published measures of hospital mortality.

Results

Of the 10 169 003 hospital admissions analysed, 11.2% had recorded diabetes, but 21.5% of inpatient deaths occurred in this group. After adjustment for case mix, hospital admissions in patients with recorded diabetes had a 6.4% greater risk of dying (2052 more deaths over 2 years) than would be expected compared with similar patients without recorded diabetes. The additional risk of death was significantly greater in smaller trusts. The highest additional risk of death was found in hospital admissions of younger female patients admitted electively. At provider trust level, 37.4% of variation in adjusted mortality in patients with recorded diabetes was explained by the mortality in those without recorded diabetes.

Conclusion

A diagnosis of diabetes has an adverse impact on hospital mortality that cannot be explained by usual case‐mix adjustments, and the additional risk of dying is greatest among hospital admissions that would normally have a low risk of death. This implies that diabetes may override the usual risk factors for hospital mortality.