The cover of living and dead corals from airborne remote sensing

Trends in coral cover are widely used to indicate the health of coral reefs but are costly to obtain from field survey over large areas. In situ studies of reflected spectra at the coral surface show that living and recently dead colonies can be distinguished. Here, we investigate whether such spectral differences can be detected using an airborne remote sensing instrument. The Compact Airborne Spectrographic Imager (Itres Research Ltd, Canada) was flown in two configurations: 10 spectral bands with 1-m² pixels and 6 spectral bands with 0.25-m² pixels. First, we show that an instrument with 10 spectral bands possesses adequate spectral resolution to distinguish living Porites, living Pocillopora spp., partially dead Porites, recently dead Porites (total colony mortality within 6 months), old dead (>6 months) Porites, Halimeda spp., and coralline red algae when there is no water column to confuse spectra. All substrata were distinguished using fourth-order spectral derivatives around 538 nm and 562 nm. Then, at a shallow site (Tivaru) at Rangiroa Atoll, Tuamotu Archipelago (French Polynesia), we show that live and dead coral can be distinguished from the air to a depth of at least 4 m using first- and fourth-order spectral derivatives between 562–580 nm. However, partially dead and recently dead Porites colonies could not be distinguished from an airborne platform. Spectral differences among substrata are then exploited to predict the cover of reef substrata in ten 25-m² plots at nearby Motu Nuhi (max depth 8 m). The actual cover in these plots was determined in situ using quadrats with a 0.01-m² grid. Considerable disparity occurred between field and image-based measures of substrate cover within individual 25-m² quadrats. At this small scale, disparity, measured as the absolute difference in cover between field and remote-sensing methods, reached 25% in some substrata but was always less than 10% for living coral (99% of which consisted of Porites spp.). At the scale of the reef (all ten 25-m² quadrats), however, disparities in percent cover between imagery and field data were less than 10% for all substrata and extremely low for some classes (e.g. <3% for living Porites, recently dead Porites and Halimeda). The least accurately estimated substrata were sand and coralline red algae, which were overestimated by absolute values 7.9% and 6.6%, respectively. The precision of sampling was similar for field and remote-sensing methods: field methods required 19 plots to detect a 10% difference in coral cover among three reefs with a statistical power of 95%. Remote-sensing methods required 21 plots. However, it took 1 h to acquire imagery over 92,500 m² of reef, which represents 3,700 plots of 25 m² each, compared with 3 days to survey 10 such plots underwater. There were no significant differences in accuracy between 1-m² and 0.25-m² image resolutions, suggesting that the advantage of using smaller pixels is offset by reduced spectral information and an increase in noise (noise was observed to be 1.6–1.8 times greater in 0.25-m² pixels). We show that airborne remote sensing can be used to monitor coral and algal cover over large areas, providing that water is shallow and clear, and that brown fleshy macroalgae are scarce, that depth is known independently (e.g. from sonar survey).     

Smoke Rings: Towards a Comprehensive Tobacco Free Policy for the Olympic Games

Background

The tobacco industry has long sought affiliation with major sporting events, including the Olympic Games, for marketing, advertising and promotion purposes. Since 1988, each Olympic Games has adopted a tobacco-free policy. Limited study of the effectiveness of the smoke-free policy has been undertaken to date, with none examining the tobacco industry’s involvement with the Olympics or use of the Olympic brand.

Methods and Findings

A comparison of the contents of Olympic tobacco-free policies from 1988 to 2014 was carried out by searching the websites of the IOC and host NOCs. The specific tobacco control measures adopted for each Games were compiled and compared with measures recommended by the WHO Tobacco Free Sports Initiative and Article 13 of the Framework Convention on Tobacco Control (FCTC). This was supported by semi-structured interviews of key informants involved with the adoption of tobacco-free policies for selected games. To understand the industry’s interests in the Olympics, the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu) was systematically searched between June 2013 and August 2014. Company websites, secondary sources and media reports were also searched to triangulate the above data sources.This paper finds that, while most direct associations between tobacco and the Olympics have been prohibited since 1988, a variety of indirect associations undermine the Olympic tobacco-free policy. This is due to variation in the scope of tobacco-free policies, limited jurisdiction and continued efforts by the industry to be associated with Olympic ideals.

Conclusions

The paper concludes that, compatible with the IOC’s commitment to promoting healthy lifestyles, a comprehensive tobacco-free policy with standardized and binding measures should be adopted by the International Olympic Committee and all national Olympic committees.     

The M/GP5 Glycoprotein Complex of Porcine Reproductive and Respiratory Syndrome Virus Binds the Sialoadhesin Receptor in a Sialic Acid-Dependent Manner

The porcine reproductive and respiratory syndrome virus (PRRSV) is a major threat to swine health worldwide and is considered the most significant viral disease in the swine industry today. In past years, studies on the entry of the virus into its host cell have led to the identification of a number of essential virus receptors and entry mediators. However, viral counterparts for these molecules have remained elusive and this has made rational development of new generation vaccines impossible. The main objective of this study was to identify the viral counterparts for sialoadhesin, a crucial PRRSV receptor on macrophages. For this purpose, a soluble form of sialoadhesin was constructed and validated. The soluble sialoadhesin could bind PRRSV in a sialic acid-dependent manner and could neutralize PRRSV infection of macrophages, thereby confirming the role of sialoadhesin as an essential PRRSV receptor on macrophages. Although sialic acids are present on the GP₃, GP₄ and GP₅ envelope glycoproteins, only the M/GP₅ glycoprotein complex of PRRSV was identified as a ligand for sialoadhesin. The interaction was found to be dependent on the sialic acid binding capacity of sialoadhesin and on the presence of sialic acids on GP₅. These findings not only contribute to a better understanding of PRRSV biology, but the knowledge and tools generated in this study also hold the key to the development of a new generation of PRRSV vaccines.     

The competitive success of Methanomicrococcus blatticola, a dominant methylotrophic methanogen in the cockroach hindgut, is supported by high substrate affinities and favorable thermodynamics

Methanomicrococcus blatticola is an obligately anaerobic methanogen that derives the energy for growth exclusively from the reduction of methylated compounds to methane with molecular hydrogen as energy source. Competition for methanol (concentration below 10 microM) and H(2) (concentration below 500 Pa), as well as oxidative stress due to the presence of oxygen are likely to occur in the peripheral region of the cockroach hindgut, the species' normal habitat. We investigated the ecophysiological properties of M. blatticola to explain how it can successfully compete for its methanogenic substrates. The organism showed affinities for methanol (K(m)=5 microM; threshold<1 microM) and hydrogen (K(m)=200 Pa; threshold <0.7 Pa) that are superior to other methylotrophic methanogens (Methanosphaera stadtmanae, Methanosarcina barkeri) investigated here. Thermodynamic considerations indicated that 'methanol respiration', i.e. the use of methanol as the terminal electron acceptor, represents an attractive mode of energy generation, especially at low hydrogen concentrations. Methanomicrococcus blatticola exploits the opportunities by specific growth rates (>0.2 h(-1)) and specific growth yields (up to 7 g of dry cells per mole of methane formed) that are particularly high within the realm of mesophilic methanogens. Upon oxygen exposure, part of the metabolic activity may be diverted into oxygen removal, thus establishing appropriate anaerobic conditions for survival and growth.     

Porcine arterivirus attachment to the macrophage-specific receptor sialoadhesin is dependent on the sialic acid-binding activity of the N-terminal immunoglobulin domain of sialoadhesin

The sialic acid-binding lectin sialoadhesin (Sn) is a macrophage-restricted receptor for porcine reproductive and respiratory syndrome virus (PRRSV). To investigate the importance of pSn sialic acid-binding activity for PRRSV infection, an R₁₁₆-to-E mutation was introduced in the predicted sialic acid-binding domain of pSn, resulting in a mutant, pSn^RE, that could not bind sialic acids. PSn, but not pSn^RE, allowed PRRSV binding and internalization. These data show that the sialic acid-binding activity of pSn is essential for PRRSV attachment to pSn and thus identifies the variable, N-terminal domain of Sn as a PRRSV binding domain.     

Protection induced in BALB/c mice by the high-molecular-mass (hMM) fraction of <Emphasis Type="Italic">Paracoccidioides brasiliensis</Emphasis>

Paracoccidioidomycosis (PCM) is a granulomatous disease caused by a dimorphic fungus, Paracoccidioides brasiliensis. The present study investigated the protective activity of the P. brasiliensis high-molecular-mass (hMM) fraction (~380 kDa) in experimental murine PCM. In the first step, lymphocyte proliferation and production of IFNγ (but not IL-4) were observed in “in vitro” spleen cells (from female BALB/c mice infected (i.v.) with P. brasiliensis) that were stimulated with hMM fractions. In the second step, female BALB/c mice were previously immunized (s.c.) with hMM fraction (25 μg/protein = F-25 and 50 μg/protein = F-50), and the colony-forming units (CFU) of the lung and spleen, the histopathological characteristics of the granulomatous lesions, and plasmatic gp43 soluble antigens and anti-hMM IgG levels were analyzed at 28 and 56 days after infection. The lung and liver CFU were lower in mice previously immunized with the hMM fraction (P < 0.05). The granulomatous lesions revealed a greater degree of compaction and organization, with no dissemination of the fungus to other organs. Lower soluble antigen levels (P < 0.05) and higher IgG anti-hMM fraction (P < 0.05) were observed in immunized groups. The results for CFU, histopathology and antigenemia suggest that the hMM fraction has a protective effect in experimental paracoccidioidomycosis in BALB/c mice.     

Gene transfer to pre-hematopoietic and committed hematopoietic precursors in the early mouse Yolk Sac: a comparative study between <Emphasis Type="Italic">in situ</Emphasis> electroporation and retroviral transduction

Background  

Hematopoietic development in vertebrate embryos results from the sequential contribution of two pools of precursors independently generated. While intra-embryonic precursors harbour the features of hematopoietic stem cells (HSC), precursors formed earlier in the yolk sac (YS) display limited differentiation and self-renewal potentials. The mechanisms leading to the generation of the precursors in both sites are still largely unknown, as are the molecular basis underlying their different potential. A possible approach to assess the role of candidate genes is to transfer or modulate their expression/activity in both sites. We thus designed and compared transduction protocols to target either native extra-embryonic precursors, or hematopoietic precursors.     

European society of intensive care medicine study of therapeutic hypothermia (32-35°C) for intracranial pressure reduction after traumatic brain injury (the Eurotherm3235Trial)

Background

Severe malaria remains a major cause of global morbidity and mortality. Despite the use of potent anti-parasitic agents, the mortality rate in severe malaria remains high. Adjunctive therapies that target the underlying pathophysiology of severe malaria may further reduce morbidity and mortality. Endothelial activation plays a central role in the pathogenesis of severe malaria, of which angiopoietin-2 (Ang-2) has recently been shown to function as a key regulator. Nitric oxide (NO) is a major inhibitor of Ang-2 release from endothelium and has been shown to decrease endothelial inflammation and reduce the adhesion of parasitized erythrocytes. Low-flow inhaled nitric oxide (iNO) gas is a US FDA-approved treatment for hypoxic respiratory failure in neonates.

Methods/Design

This prospective, parallel arm, randomized, placebo-controlled, blinded clinical trial compares adjunctive continuous inhaled nitric oxide at 80 ppm to placebo (both arms receiving standard anti-malarial therapy), among Ugandan children aged 1-10 years of age with severe malaria. The primary endpoint is the longitudinal change in Ang-2, an objective and quantitative biomarker of malaria severity, which will be analysed using a mixed-effects linear model. Secondary endpoints include mortality, recovery time, parasite clearance and neurocognitive sequelae.

Discussion

Noteworthy aspects of this trial design include its efficient sample size supported by a computer simulation study to evaluate statistical power, meticulous attention to complex ethical issues in a cross-cultural setting, and innovative strategies for safety monitoring and blinding to treatment allocation in a resource-constrained setting in sub-Saharan Africa.

Trial Registration

ClinicalTrials.gov Identifier: NCT01255215     

The Khatri Sikh Diabetes Study (SDS): study design, methodology, sample collection, and initial results

Non-insulin-dependent diabetes mellitus, or type 2 diabetes (T2DM), has become a major public health problem in India. The high prevalence, relatively young age of onset, and strong familial aggregation of T2DM in some Indian communities remains to be explained. Many of the traditional risk factors established for European populations do not appear to be present in Asian Indians. Phase I of the Sikh Diabetes Study (SDS) was launched to build the population resources required to initiate a large-scale genetic epidemiological study of diabetes in an Asian Indian population. The SDS is focused on the Khatri Sikh population of North India. In all, 1,892 subjects were enrolled to participate in the family-based study; 1,623 of these subjects belong to 324 families, each of which has at least 2 siblings affected with T2DM. The sample included 1,288 individuals affected with T2DM (siblings, parents, or relatives) and 335 unaffected siblings, parents, or relatives. The remaining 269 subjects were unrelated nondiabetic control subjects, including unaffected spouses of probands or siblings. This primarily nonvegetarian, nonsmoking endogamous caste group has presented an unusual clinical picture of uneven distribution of adiposity and a high rate of T2DM with secondary complications. Such well-characterized population isolates may offer unique advantages in mapping genes for common complex diseases.