The Interaction between Root Distribution and Pasture Growth During Water Deficit

Quantification of water-limited pasture growth is of interest in agriculture since it allows prediction of impaired animal production during drought, and is the basis for scheduling irrigation. Experimental work on two dairy pastures 25 km south-west of Palmerston North, New Zealand found 50% of root mass was in the top 2.3 cm of soil. Soil moisture was, similarly, not uniformly distributed down the soil profile and dried most rapidly in the top 20†cm of soil. Leaf appearance rate was more strongly correlated with water status nearer the soil surface (r = 0.52 & 0.63 for 0-5 & 10-15 cm depth, respectively) than at depth (r = 0.13 for 20-70 cm depth). Water-limiting pasture growth models need to account for the distribution of roots and water in the soil to accurately predict growth of pastures subjected to, and recovering from, water deficit

Antimicrobial susceptibilities in dairy herds that differ in dry cow therapy usage

Intramammary infusion of antimicrobials at the end of lactation (dry cow therapy; DCT) is a central part of mastitis control programs and is one of the major indications for antimicrobial use in dairy cows. However, with increasing focus on prudent use of antimicrobials and concerns about emergence of antimicrobial resistance, the practice of treating every cow at the end of lactation with DCT is in question. This cross-sectional, observational study determined the minimum inhibitory concentrations (MIC) of 10 antimicrobials for coagulase-negative staphylococci (CNS), Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis isolates from milk samples from dairy cows with somatic cell counts >200,000 cells/mL in herds that had been organic for >3 yr (n = 7), or had used either ampicillin-cloxacillin DCT (n = 11) or cephalonium DCT (n = 8) in the preceding 3 yr. The organic herds were certified under the United States Department of Agriculture National Organic Program, meaning that there was no blanket DCT, and minimal use of antimicrobials in general, with a loss of organic status of the animal if treated with antimicrobials. Breakpoints (where available) were used to categorize isolates as resistant, intermediate, or susceptible to antimicrobials. The MIC distributions of isolates from different herd types were compared using binomial or multinomial logistic regression. Of 240 CNS isolates, 12.9, 0.8, 7.1, 32.6, and 1.2%, were intermediate or resistant to ampicillin, cephalothin, erythromycin, penicillin, and tetracycline, respectively. Of 320 Staph. aureus isolates, 29.0, 2.5, 1.2, and 34.9% were intermediately resistant or resistant to ampicillin, penicillin, erythromycin, and oxacillin, respectively. Of 184 Strep. uberis isolates, 1.1, 25.0, 1.6, and 1.6% were intermediately resistant or resistant to erythromycin, penicillin, pirlimycin, and tetracycline, respectively. Generally, the MIC of CNS and streptococcal isolates from organic herds were lower than isolates from herds using DCT. However, the differences in MIC distributions occurred at MIC below clinical breakpoints, so that the bacteriological cure rates may not differ between isolates of differing MIC. Bimodal distributions of MIC for ampicillin and penicillin were found in Staph. aureus isolates from organic herds, suggesting that isolates with a higher MIC are a natural part of the bacterial population of the bovine mammary gland, or that isolates with higher MIC have persisted within these organic herds from a time when antimicrobials had been used. Given these observations, further work is required to determine if exposure to DCT is causally associated with the risk of elevated MIC, and whether reduction or removal of DCT from herds would reduce the risk of elevated MIC of mastitis pathogens.fals

Spin states of asteroids in the Eos collisional family

Eos family was created during a catastrophic impact about 1.3 Gyr ago. Rotation states of individual family members contain information about the history of the whole population. We aim to increase the number of asteroid shape models and rotation states within the Eos collision family, as well as to revise previously published shape models from the literature. Such results can be used to constrain theoretical collisional and evolution models of the family, or to estimate other physical parameters by a thermophysical modeling of the thermal infrared data. We use all available disk-integrated optical data (i.e., classical dense-in-time photometry obtained from public databases and through a large collaboration network as well as sparse-in-time individual measurements from a few sky surveys) as input for the convex inversion method, and derive 3D shape models of asteroids together with their rotation periods and orientations of rotation axes. We present updated shape models for 15 asteroids and new shape model determinations for 16 asteroids. Together with the already published models from the publicly available DAMIT database, we compiled a sample of 56 Eos family members with known shape models that we used in our analysis of physical properties within the family. Rotation states of asteroids smaller than ~20 km are heavily influenced by the YORP effect, whilst the large objects more or less retained their rotation state properties since the family creation. Moreover, we also present a shape model and bulk density of asteroid (423) Diotima, an interloper in the Eos family, based on the disk-resolved data obtained by the Near InfraRed Camera (Nirc2) mounted on the W.M. Keck II telescope.Comment: Accepted for publication in ICARUS Special Issue - Asteroids: Origin, Evolution & Characterizatio

As-yet-uncultivated oral bacteria: breadth and association with oral and extra-oral diseases

It has been shown that 40–60% of the bacteria found in different healthy and diseased oral sites still remain to be grown in vitro, phenotypically characterized, and formally named as species. The possibility exists that these as-yet-uncultivated bacteria play important ecological roles in oral bacterial communities and may participate in the pathogenesis of several oral infectious diseases. There is also a potential for these as-yet-uncultivated oral bacteria to take part in extra-oral infections. For a comprehensive characterization of physiological and pathogenic properties as well as antimicrobial susceptibility of individual bacterial species, strains need to be grown in pure culture. Advances in culturing techniques have allowed the cultivation of several oral bacterial taxa only previously known by a 16S rRNA gene sequence signature, and novel species have been proposed. There is a growing need for developing improved methods to cultivate and characterize the as-yet-uncultivated portion of the oral microbiome so as to unravel its role in health and disease

Conducting sexualities research: An outline of emergent issues and case studies from ten wellcome-funded projects [version 1; peer review: 3 approved]

© 2019 Kneale D et al. This letter seeks to synthesise methodological challenges encountered in a cohort of Wellcome Trust-funded research projects focusing on sexualities and health. The ten Wellcome Trust projects span a diversity of gender and sexual orientations and identities, settings; institutional and non-institutional contexts, lifecourse stages, and explore a range of health-related interventions. As researchers, we originate from a breadth of disciplinary traditions, use a variety of research methods and data sources. Despite this breadth, four common themes are found across the projects: (i) inclusivity representations and representativeness, (ii) lumping together of diverse groups, (iii) institutions and closed settings (iv) ethical and governance barriers

Conducting sexualities research: an outline of emergent issues and case studies from ten Wellcome-funded projects [version 1; peer review: awaiting peer review]

This letter seeks to synthesise methodological challenges encountered in a cohort of Wellcome Trust-funded research projects focusing on sexualities and health. The ten Wellcome Trust projects span a diversity of gender and sexual orientations and identities, settings; institutional and non-institutional contexts, lifecourse stages, and explore a range of health-related interventions.  As researchers, we originate from a breadth of disciplinary traditions, use a variety of research methods and data sources. Despite this breadth, four common themes are found across the projects: (i) inclusivity, representations and representativeness, (ii) lumping together of diverse groups, (iii) institutions and closed settings (iv) ethical and governance barriers

Quality assurance, benchmarking, assessment and mutual international recognition of qualifications

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