The Formation of the Double Pulsar PSR J0737-3039A/B

Recent timing observations of the double pulsar J0737-3039A/B have shown that its transverse velocity is extremely low, only 10 km/s, and nearly in the Plane of the Galaxy. With this new information, we rigorously re-examine the history and formation of this system, determining estimates of the pre-supernova companion mass, supernova kick and misalignment angle between the pre- and post-supernova orbital planes. We find that the progenitor to the recently formed `B' pulsar was probably less than 2 MSun, lending credence to suggestions that this object may not have formed in a normal supernova involving the collapse of an iron core. At the same time, the supernova kick was likely non-zero. A comparison to the history of the double-neutron-star binary B1534+12 suggests a range of possible parameters for the progenitors of these systems, which should be taken into account in future binary population syntheses and in predictions of the rate and spatial distribution of short gamma-ray burst events.Comment: To appear in MNRAS Letters. Title typo fix only; no change to pape

Lean meat yield estimation using a prototype 3D imaging approach.

Lean Meat Yield (LMY, %) of carcass is an important industry trait, which currently is not routinely measured in Australian beef abattoirs. Objective on-line technology to determine LMY is key for wider adoption. This paper presents a proof-of-concept approach for estimating the LMY of beef carcasses from the 3D information provided by RGB-D cameras. Moreover, a specifically designed on-line data acquisition system for abattoir applications is presented, consisting of three cameras moving on a scanning rig to generate 3D carcass side reconstructions. The hindquarter is then segmented consistently across all the 3D models to extract curvature information and LMY estimated via non-linear regression based on Gaussian Process models. Sides from 119 carcasses at two different commercial abattoirs were used to evaluate this approach. Results from this preliminary study (RMSE = 3.91%, R2 = 0.69) using curvature, P8 fat and HSCW indicate that 3D imaging of beef carcasses is a viable and relatively accurate technology to estimate LMY

Recognition of envelope and tat protein synthetic peptide analogs by HIV positive sera or plasma

AbstractA series of synthetic peptides corresponding to segments of HIV encoded proteins were selected using criteria described by Welling et al. [(1985) FEBS Lett. 188, 215]. Synthetic peptide analogs to gpl20 (2–13), (55–65), gp41 (582–596) (659–670) and tatIII (71–83) were recognized by 41–67% of sera or plasma from individuals known to be infected with HIV on the basis of virus isolation or Western blot screening. The peptide which reacted with most sera or plasma was gp41 (582–596), a conserved region in the transmembrane glycoprotein. An extended peptide analog, gp41 (579–599), tested against the same samples showed almost 100% reactivity, confirming independent studies identifying a highly immunodominant region of gp41. There was an unexpected high prevalence of antibodies (52%) to the tatIII peptide

The subduction experiment : cruise report R/V Knorr : cruise number 138 leg XV : subduction 3 mooring recovery cruise, 13-30 June 1993

Subduction is the mechanism by which water masses formed in the mixed layer and near the surface of the ocean find their way into the upper thermocline. The subduction process and its underlying mechanisms were studied though a combination of Eulerian and Langrangian measurements of velocity, measurements of tracer distributions and hydrographic properties and modeling. An array of five surface moorings carrying meteorological and oceanographic instrumentation were deployed for a period of two years beginning in June 1991 as part of an Office of Naval Research (ONR) funded Subduction experiment. Three eight month deployments were planned. The moorings were deployed at 18°N 34°W, 18°N 22°W, 25.5°N 29°W, 33°N 22°W and 33°N 34°W. A Vector Averaging Wind Recorder (VAWR) and an Improved Meteorological Recorder (IMET) collected wind speed and wind direction, sea surface temperature, air temperature, short wave radiation, barometric pressure and relative humidity. The IMET also measured precipitation. The moorings were heavily instrumented below the surface with Vector Measuring Current Meters (VMCM) and single point temperature recorders. Expendable bathythermograph (XBT) data were collected and meteorological observations were made while transmitting between mooring locations. This report describes the work that took place during R/V Knorr cruise number 138 leg XV which was the fourth scheduled Subduction mooring cruise. During this cruise the moorings previously deployed for a third and final eight month period were recovered. This report includes a description of the moorings and instrumentation that were recovered, has information about the underway measurements (XBT and meteorological observations) that were made including plots of the data, and presents a chronology of the cruise events.Funding provided by the Office of Naval Research under Contract No. N00014-90-J-1490

Human skeletal muscle fibre contractile properties and proteomic profile: Adaptations to 3 weeks of unilateral lower limb suspension and active recovery

Following disuse, muscle fibre function goes through adaptations such as a loss of specific force (PO/CSA) and an increase in unloaded shortening velocity, which could be a result of both quantitative changes (i.e. atrophy) and qualitative changes in protein pattern. The underlying mechanisms remain to be clarified. In addition, little is known about the recovery of muscle mass and strength following disuse. In the present study, we report an extensive dataset describing, in detail,the functional and protein content adaptations of skeletal muscle in response to both disuse and re-training. Eight young healthy subjects were subjected to 3 weeks of unilateral lower limb suspension (ULLS), a widely used human model of disuse skeletal muscle atrophy. Needle biopsies samples were taken from the vastus lateralis muscle Pre-ULLS, Post-ULLS and after 3 weeks of recovery during which heavy resistance training was performed. After disuse, cross-sectional area (CSA), PO/CSA and myosin concentration (MC) decreased in both type 1 and 2A skinned muscle fibres. After recovery, CSA and MC returned to levels comparable to those observed before disuse, whereas Po/CSA and unloaded shortening velocity reached a higher level. Myosin heavy chain isoform composition of muscle samples did not differ among the experimental groups. To study the mechanisms underlying such adaptations, a two-dimensional proteomic analysis was performed. ULLS induced a reduction of myofibrillar, metabolic (glycolytic and oxidative) and anti-oxidant defence system protein content. Resistance training was very effective in counteracting ULLS-induced alterations, indicating that long-term ULLS did not prevent the positive effect of exercise on human muscle. © 2015 The Physiological Society

Maladaptation in Feral and Domesticated Animals

Selection regimes and population structures can be powerfully changed by domestication and feralization, and these changes can modulate animal fitness in both captive and natural environments. In this review, we synthesize recent studies of these two processes and consider their impacts on organismal and population fitness. Domestication and feralization offer multiple windows into the forms and mechanisms of maladaptation. Firstly, domestic and feral organisms that exhibit suboptimal traits or fitness allow us to identify their underlying causes within tractable research systems. This has facilitated significant progress in our general understandings of genotype–phenotype relationships, fitness trade‐offs, and the roles of population structure and artificial selection in shaping domestic and formerly domestic organisms. Additionally, feralization of artificially selected gene variants and organisms can reveal or produce maladaptation in other inhabitants of an invaded biotic community. In these instances, feral animals often show similar fitness advantages to other invasive species, but they are also unique in their capacities to modify natural ecosystems through introductions of artificially selected traits. We conclude with a brief consideration of how emerging technologies such as genome editing could change the tempos, trajectories, and ecological consequences of both domestication and feralization. In addition to providing basic evolutionary insights, our growing understanding of mechanisms through which artificial selection can modulate fitness has diverse and important applications—from enhancing the welfare, sustainability, and efficiency of agroindustry, to mitigating biotic invasions

Dietary protein intake, breast feeding and growth in human milk fed preterm infants

Protein intakes of preterm infants are frequently below recommendations, but few studies report accurate intakes due to the difficulty of analysing human milk clinically. This observational analysis from a randomised trial of infants born <31 weeks’ gestation, investigating two levels of protein fortification, reports protein intakes compared with requirements and determines the association of direct breastfeeding on growth. Ninety-two infants (median gestational age 28 weeks, Interquartile range (IQR) 26–29; mean birth weight 1040 g, SD 300 g) were studied. Infants born weighing <1000 g were underfed protein compared with recommendations (median (IQR) intake of 3.0 (2.0–3.7) g/kg/day in week 2 versus recommendation of 4–4.5 g/kg/day), while those born weighing ≥1000 g met recommended protein intakes after the first week of life (median (IQR) intake of 3.7 (3.0–4.0) g/kg/day in week 2 versus recommendation of 3.5–4.5 g/kg/day). A moderate, negative correlation between the mean number of breast feeds and change in rate of weight gain (r = −0.37, p = 0.001) was found. Protein intakes of infants <1000 g did not meet recommendations and all infants were underfed protein and energy in the first week of life. Current protein fortification is inadequate for infants born <1000 g. Exploratory analysis showed faltering rate weight gain associated with increasing number of breast feeds and these results warrant confirmation.Emma Tonkin, Jacqueline Miller, Maria Makrides, Andrew J. McPhee, Scott A. Morris, Robert A. Gibson and Carmel T. Collin