Understanding the direct and indirect mechanisms of xylanase action on starch digestion in broilers

The objective of the current study was to investigate the mechanisms of xylanase action in a maize-soya diet and its effect on starch digestion. A total of 60 broilers were divided into 6 treatment groups; a control group without xylanase, and five other groups supplemented with xylanase (Econase XT 25; 100 g/t) from 1, 2, 3, 4 or 5 weeks before slaughter. At the end of the experiment, digesta was collected from the gizzard, upper and lower small intestine, and both caeca. Digesta pH ranged from pH 2.2-4.4, 5.9-6.6, 6.7-7.8 and 5.7-7.3 in the gizzard, upper small intestine, lower small intestine, and both caeca, respectively, with no effect of xylanase (P > 0.05). Scanning Electron Microscope (SEM) images along with total starch measurements showed the progression of starch digestion through the tract. The SEM did not show any greater disruption to cell wall material with xylanase supplementation. This suggests that xylanase was not working directly on the cell wall and provides evidence for the hypothesis that xylanase works through an indirect mechanism. Peptide YY (PYY) concentration in the blood was higher during the first few weeks of supplementation, with longer periods of supplementation nulling this effect, implying that xylanase may be acting through a prebiotic mechanism. The RT-q PCR results revealed a numerical increase in glucose transporter (GLUT2 and SGLT1) expression at 2 and 3 weeks of xylanase supplementation, respectively, which might suggest a greater absorption capacity of birds. From these results, a potential mechanism of xylanase action in maize-based diets has been proposed

Relating characteristics of global biodiversity targets to reported progress

To inform governmental discussions on the nature of a revised Strategic Plan for Biodiversity of the Convention on Biological Diversity (CBD), we reviewed the relevant literature and assessed the framing of the 20 Aichi Biodiversity Targets in the current strategic plan. We asked international experts from nongovernmental organizations, academia, government agencies, international organizations, research institutes, and the CBD to score the Aichi Targets and their constituent elements against a set of specific, measurable, ambitious, realistic, unambiguous, scalable, and comprehensive criteria (SMART based, excluding time bound because all targets are bound to 2015 or 2020). We then investigated the relationship between these expert scores and reported progress toward the target elements by using the findings from 2 global progress assessments (Global Biodiversity Outlook and the Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services). We analyzed the data with ordinal logistic regressions. We found significant positive relationships (p < 0.05) between progress and the extent to which the target elements were perceived to be measurable, realistic, unambiguous, and scalable. There was some evidence of a relationship between progress and specificity of the target elements, but no relationship between progress and ambition. We are the first to show associations between progress and the extent to which the Aichi Targets meet certain SMART criteria. As negotiations around the post‐2020 biodiversity framework proceed, decision makers should strive to ensure that new or revised targets are effectively structured and clearly worded to allow the translation of targets into actionable policies that can be successfully implemented nationally, regionally, and globally

Below the canopy: global trends in forest vertebrate populations and their drivers

Global forest assessments use forest area as an indicator of biodiversity status, which may mask below-canopy pressures driving forest biodiversity loss and 'empty forest' syndrome. The status of forest biodiversity is important not only for species conservation but also because species loss can have consequences for forest health and carbon storage. We aimed to develop a global indicator of forest specialist vertebrate populations to improve assessments of forest biodiversity status. Using the Living Planet Index methodology, we developed a weighted composite Forest Specialist Index for the period 1970-2014. We then investigated potential correlates of forest vertebrate population change. We analysed the relationship between the average rate of change of forest vertebrate populations and satellite-derived tree cover trends, as well as other pressures. On average, forest vertebrate populations declined by 53% between 1970 and 2014. We found little evidence of a consistent global effect of tree cover change on forest vertebrate populations, but a significant negative effect of exploitation threat on forest specialists. In conclusion, we found that the forest area is a poor indicator of forest biodiversity status. For forest biodiversity to recover, conservation management needs to be informed by monitoring all threats to vertebrates, including those below the canopy

Reframing the concept of alternative livelihoods

Alternative livelihood project (ALP) is a widely used term for interventions that aim to reduce the prevalence of activities deemed to be environmentally damaging by substituting them with lower impact livelihood activities that provide at least equivalent benefits. ALPs are widely implemented in conservation, but in 2012, an International Union for Conservation of Nature resolution called for a critical review of such projects based on concern that their effectiveness was unproven. We focused on the conceptual design of ALPs by considering their underlying assumptions. We placed ALPs within a broad category of livelihood-focused interventions to better understand their role in conservation and their intended impacts. We dissected 3 flawed assumptions about ALPs based on the notions of substitution, the homogenous community, and impact scalability. Interventions based on flawed assumptions about people's needs, aspirations, and the factors that influence livelihood choice are unlikely to achieve conservation objectives. We therefore recommend use of a sustainable livelihoods approach to understand the role and function of environmentally damaging behaviors within livelihood strategies; differentiate between households in a community that have the greatest environmental impact and those most vulnerable to resource access restrictions to improve intervention targeting; and learn more about the social–ecological system within which household livelihood strategies are embedded. Rather than using livelihood-focused interventions as a direct behavior-change tool, it may be more appropriate to focus on either enhancing the existing livelihood strategies of those most vulnerable to conservation-imposed resource access restrictions or on use of livelihood-focused interventions that establish a clear link to conservation as a means of building good community relations. However, we recommend that the term ALP be replaced by the broader term livelihood-focused intervention. This avoids the implicit assumption that alternatives can fully substitute for natural resource-based livelihood activities

Cometary ions detected by the Cassini spacecraft 6.5 au downstream of Comet 153P/Ikeya-Zhang

During March-April 2002, while between the orbits of Jupiter and Saturn, the Cassini spacecraft detected a significant enhancement in pickup proton flux. The most likely explanation for this enhancement was the addition of protons to the solar wind by the ionization of neutral hydrogen in the corona of comet 153P/Ikeya-Zhang. This comet passed relatively close to the Sun-Cassini line during that period, allowing pickup ions to be carried to Cassini by the solar wind. This pickup proton flux could have been further modulated by the passage of the interplanetary counterparts of coronal mass ejections past the comet and spacecraft. The radial distance of 6.5 Astronomical Units (au) traveled by the pickup protons, and the implied total tail length of 7.5 au make this cometary ion tail the longest yet measured

Modelling-based evaluation of the costs, benefits and cost-effectiveness of multipathogen point-of-care tests for sexually transmitted infections in symptomatic genitourinary medicine clinic attendees

Objectives To quantify the costs, benefits and cost-effectiveness of three multipathogen point-of-care (POC) testing strategies for detecting common sexually transmitted infections (STIs) compared with standard laboratory testing. Design Modelling study. Setting Genitourinary medicine (GUM) services in England. Population A hypothetical cohort of 965 988 people, representing the annual number attending GUM services symptomatic of lower genitourinary tract infection. Interventions The decision tree model considered costs and reimbursement to GUM services associated with diagnosing and managing STIs. Three strategies using hypothetical point-of-care tests (POCTs) were compared with standard care (SC) using laboratory-based testing. The strategies were: A) dual POCT for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG); B) triplex POCT for CT-NG and Mycoplasma genitalium (MG); C) quadruplex POCT for CT-NG-MG and Trichomonas vaginalis (TV). Data came from published literature and unpublished estimates. Primary and secondary outcome measures Primary outcomes were total costs and benefits (quality-adjusted life years (QALYs)) for each strategy (2016 GB, £) and associated incremental cost-effectiveness ratios (ICERs) between each of the POC strategies and SC. Secondary outcomes were inappropriate treatment of STIs, onward STI transmission, pelvic inflammatory disease in women, time to cure and total attendances. Results In the base-case analysis, POC strategy C, a quadruplex POCT, was the most cost-effective relative to the other strategies, with an ICER of £36 585 per QALY gained compared with SC when using microcosting, and cost-savings of £26 451 382 when using tariff costing. POC strategy C also generated the most benefits, with 240 467 fewer clinic attendances, 808 fewer onward STI transmissions and 235 135 averted inappropriate treatments compared with SC. Conclusions Many benefits can be achieved by using multipathogen POCTs to improve STI diagnosis and management. Further evidence is needed on the underlying prevalence of STIs and SC delivery in the UK to reduce uncertainty in economic analyses

Targeting TLR4 during vaccination boosts MAdCAM-1+ lymphoid stromal cell activation and promotes the aged germinal center response

The failure to generate enduring humoral immunity after vaccination is a hallmark of advancing age. This can be attributed to a reduction in the germinal center (GC) response, which generates long-lived antibody-secreting cells that protect against (re)infection. Despite intensive investigation, the primary cellular defect underlying impaired GCs in aging has not been identified. Here, we used heterochronic parabiosis to demonstrate that GC formation was dictated by the age of the lymph node (LN) microenvironment rather than the age of the immune cells. Lymphoid stromal cells are a key determinant of the LN microenvironment and are also an essential component underpinning GC structure and function. Using mouse models, we demonstrated that mucosal adressin cell adhesion molecule-1 (MAdCAM-1)-expressing lymphoid stromal cells were among the first cells to respond to NP-KLH + Alum immunization, proliferating and up-regulating cell surface proteins such as podoplanin and cell adhesion molecules. This response was essentially abrogated in aged mice. By targeting TLR4 using adjuvants, we improved the MAdCAM-1+ stromal cell response to immunization. This correlated with improved GC responses in both younger adult and aged mice, suggesting a link between stromal cell responses to immunization and GC initiation. Using bone marrow chimeras, we also found that MAdCAM-1+ stromal cells could respond directly to TLR4 ligands. Thus, the age-associated defect in GC and stromal cell responses to immunization can be targeted to improve vaccines in older people

Prescribing practices of primary-care veterinary practitioners in dogs diagnosed with bacterial pyoderma

Concern has been raised regarding the potential contributions of veterinary antimicrobial use to increasing levels of resistance in bacteria critically important to human health. Canine pyoderma is a frequent, often recurrent diagnosis in pet dogs, usually attributable to secondary bacterial infection of the skin. Lesions can range in severity based on the location, total area and depth of tissue affected and antimicrobial therapy is recommended for resolution. This study aimed to describe patient signalment, disease characteristics and treatment prescribed in a large number of UK, primary-care canine pyoderma cases and to estimate pyoderma prevalence in the UK vet-visiting canine population

Pressure-dependent water absorption cross sections for exoplanets and other atmospheres

Many atmospheres (cool stars, brown dwarfs, giant planets, extrasolar planets) are predominately composed of molecular hydrogen and helium. H216O is one of the best measured molecules in extrasolar planetary atmospheres to date and a major compound in the atmospheres of brown-dwarfs and oxygen-rich cool stars, yet the scope of experimental and theoretical studies on the pressure broadening of water vapour lines by collision with hydrogen and helium remains limited. Theoretical H2- and He-broadening parameters of water vapour lines (rotational quantum number J up to 50) are obtained for temperatures in the range 300–2000 K. Two approaches for calculation of line widths were used: (i) the averaged energy difference method and (ii) the empirical expression for J′J″-dependence. Voigt profiles based on these widths and the BT2 line list are used to generate high resolution (View the MathML source) pressure broadened cross sections for a fixed range of temperatures and pressures between 300 and 2000 K and 0.001–10 bar. An interpolation procedure which can be used to determine cross sections at intermediate temperature and pressure is described. Pressure broadening parameters and cross sections are presented in new ExoMol format