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R4586 --> 524.8 --> The overall goal of this project is to define the magnitude, quality, and duration of the primary immune response elicited against SARS‐CoV‐2 Spike by measuring domain‐specific antibody abundance and binding characteristics in plasmas after infection and vaccination. This investigation has enabled initiation of the screening of convalescent plasma polyclonal antibody (pAb) abundance and specificity through the IMPACC (Immunophenotyping Assessment in a COVID‐19 Cohort) at Drexel U College of Medicine (DUCOM) in collaboration with Tower Health Hospitals. We measured the active concentration of pAbs specific for RBD, S1 and S2 domains using SPR (surface plasmon resonance) molecular interaction analysis. By adopting a kinetic format, a complementary SPR analysis step was optimized to determine the binding rates and affinities of elicited antibodies targeting each domain of the Spike using the same plasma dilution aliquot. Most importantly, we found that the abundance of S2 reactive antibodies was comparable to that of anti‐S1 and RBD in convalescent plasmas. Plasmas obtained up to 6 months post‐vaccination are also becoming available through the TTC (Vaccination TetraCore cohort) assessment at DUCOM, and screening for these has demonstrated that anti‐S2 pAbs are also elicited, though intriguingly in lower abundance than after infection. To assess the importance anti‐S2 antibodies from convalescent plasmas, we purified anti‐S2 fractions by an SPR‐based microaffinity method and used the recovered antibodies in pseudovirus infection inhibition assays of ACE2 expressing cells to measure neutralization activity. Evidence for sustained generation of S2 antibodies up to 6 months post‐infection and occurrence of neutralizing anti‐S2 pAbs has begun to emerge with the possibility that antibodies targeting the S2 domain of the SARS‐CoV‐2 spike protein complex could provide pan‐coronavirus protection against COVID‐19, emerging variants, and other coronaviruses with conserved spike structures. Targeting the more conserved fusion machinery in the virus spike ultimately can lead to therapeutic antibodies or small molecule inhibitors effective on escape variants that occur mainly in S1 as well as other coronaviruses. [ABSTRACT FROM AUTHOR]

Abstract: Electroporation of DNA vaccines represents a platform technology well positioned for the development of multivalent biodefense vaccines. To evaluate this hypothesis, three vaccine constructs were produced using codon-optimized genes encoding Bacillus anthracis Protective Antigen (PA), and the Yersinia pestis genes LcrV and F1, cloned into pVAX1. A/J mice were immunized on a prime-boost schedule with these constructs using the electroporation-based TriGrid Delivery System. Immunization with the individual pDNA vaccines elicited higher levels of antigen-specific IgG than when used in combination. DNA vaccine effectiveness was proven, the pVAX-PA titers were toxin neutralizing and fully protective against a lethal B. anthracis spore challenge when administered alone or co-formulated with the plague pDNA vaccines. LcrV and F1 pVAX vaccines against plague were synergistic, resulting in 100% survival, but less protective individually and when co-formulated with pVAX-PA. These DNA vaccine responses were Th1/Th2 balanced with high levels of IFN-γ and IL-4 in splenocyte recall assays, contrary to complimentary protein Alum vaccinations displaying a Th2 bias with increased IL-4 and low levels of IFN-γ. These results demonstrate the feasibility of electroporation to deliver and maintain the overall efficacy of an anthrax-plague DNA vaccine cocktail whose individual components have qualitative immunological differences when combined. [Copyright &y& Elsevier]

The characteristics of densification and distortion of a 80W–14Ni–6Cu alloy during liquid-phase sintering (LPS) were investigated in relation to the liquid-phase formation. By means of differential thermal analysis (DTA), the melting process of the Ni–Cu matrix in a die-pressed compact was examined and compared with that in a loose powder mixture. It was revealed that enhanced inter-diffusion and in situ alloying occur between the tightly compacted elemental Cu and Ni powders during heating, leading to an extended temperature range for Ni–Cu liquid formation. Dilatometry and furnace sintering tests showed that the early melting of the Ni–Cu matrix results in an onset of liquid-phase sintering at a lower temperature with die compaction. Full densification of the compact, together with satisfactory microstructure, can be achieved prior to full melting of the Ni–Cu matrix. Distortion is delayed until the end of liquid-phase formation. [Copyright &y& Elsevier]

Abstract: The expression of 34 transmitter-related genes has been examined in the cholinergic neurones of rat striatal brain slices, with the aim of correlating gene expression with functional activity. The mRNAs encoding types I, II/IIA, and III α subunits of the voltage-sensitive sodium channels were detected, suggesting the presence of these three types of sodium channel. Similarly, mRNAs encoding all four α-amino-3-hydroxy-5-methyl-isoxazole-4-propionate (AMPA)-type glutamate receptor subunits and the NR1 and NR2A, 2B, and 2D subunits of the NMDA-type glutamate receptors were detected, suggesting that various combinations of these subunits mediate the cellular response to synaptically released glutamate. Other mRNAs detected included the NK1 and NK3 tachykinin receptors, all four known adenosine receptors, and the GABA-synthesising enzyme glutamate decarboxylase. Subpopulations of these cholinergic neurones have been identified on the basis of the expression of the NK3 tachykinin receptor in 5% and the trkC neurotrophin receptor in 12% of the cells investigated. [ABSTRACT FROM AUTHOR]

• Increased sheep foot temperature was associated with higher hoof lesion score. • Front and back feet with a severe lesion score had a mean temperature of 29°C or more. • Monitoring the temperature of back feet could be used to manage hoof lesions. Lameness, predominantly caused by footrot and interdigital dermatitis, is a common issue in sheep flocks with negative consequences for animal welfare and productivity. Simple and cheap methods to prevent and monitor lameness are desirable to decrease prevalence within flocks. The aim of this study was to investigate whether a high foot temperature threshold can be used as an early warning for the development of hoof lesions and lameness in sheep. A flock of 47 pregnant ewes and seven non-pregnant ewe lambs were randomly allocated into two equal groups and placed in two different but similar permanent pasture fields for the duration of the study. Foot temperature was measured with a temperature probe placed on the interdigital skin on three dates over approximately 4 weeks. This study showed that increased foot temperature was associated with higher lesion scores (recorded lesions covered a scale of 0 to 3), with healthy feet having a mean temperature of 20°C and feet with severe lesion scores having a mean temperature of 31°C. Also, back feet had a higher foot temperature and lesion score than front feet (P<0.001). This study suggests that a threshold of 26.5°C in the back feet of sheep (mean foot temperature for a lesion score of 1 in back feet) could be used as an indication of when to foot bath or treat feet, and minimise hoof lesions in sheep. [ABSTRACT FROM AUTHOR]

This study examines the effectiveness of a model called LINGRA-N-Plus to simulate the interaction of climate, soil and management on the green leaf and total dry matter yields of ryegrass in England and Wales. The LINGRA-N-Plus model includes modifications of the LINGRA-N model such as temperature- and moisture-dependent soil nitrogen mineralization and differential partitioning to leaves and stems with thermal time from the last harvest. The resulting model was calibrated against the green leaf and total grass yields from a harvest interval x nitrogen application experiment described by Wilman et al. (1976). When the LINGRA-N-Plus model was validated against total grass yields from nitrogen experiments at ten sites described by Morrison et al. (1980), its modelling efficiency improved greatly compared to the original LINGRA-N. High predicted yields, at zero nitrogen application, were related to soils with a high initial nitrogen content. The lowest predicted yields occurred at sites with low rainfall and shallow rooting depth; mitigating the effect of drought at such sites increased yields by up to 4 t ha−1. The results highlight the usefulness of grass models, such as LINGRA-N-Plus, to explore the combined effects of climate, soil, and management, like nitrogen application, and harvest intervals on grass productivity. [ABSTRACT FROM AUTHOR]

This paper proposes a novel paradigm for the unsupervised learning of object landmark detectors. Contrary to existing methods that build on auxiliary tasks such as image generation or equivariance, we propose a self-training approach where, departing from generic keypoints, a landmark detector and descriptor is trained to improve itself, tuning the keypoints into distinctive landmarks. To this end, we propose an iterative algorithm that alternates between producing new pseudo-labels through feature clustering and learning distinctive features for each pseudo-class through contrastive learning. With a shared backbone for the landmark detector and descriptor, the keypoint locations progressively converge to stable landmarks, filtering those less stable. Compared to previous works, our approach can learn points that are more flexible in terms of capturing large viewpoint changes. We validate our method on a variety of difficult datasets, including LS3D, BBCPose, Human3.6M and PennAction, achieving new state of the art results. Code and models can be found at https://github.com/dimitrismallis/KeypointsToLandmarks/.

The aim of this study was to investigate variability in enteric CH 4 emission rate and emissions per unit of milk across lactations among dairy cows on commercial farms in the UK. A total of 105,701 CH 4 spot measurements were obtained from 2206 mostly Holstein-Friesian cows on 18 dairy farms using robotic milking stations. Eleven farms fed a partial mixed ration (PMR) and 7 farms fed a PMR with grazing. Methane concentrations (ppm) were measured using an infrared CH 4 analyser at 1s intervals in breath samples taken during milking. Signal processing was used to detect CH 4 eructation peaks, with maximum peak amplitude being used to derive CH 4 emission rate (g/min) during each milking. A multiple-experiment meta-analysis model was used to assess effects of farm, week of lactation, parity, diet, and dry matter intake (DMI) on average CH 4 emissions (expressed in g/min and g/kg milk) per individual cow. Estimated mean enteric CH 4 emissions across the 18 farms was 0.38 (s.e. 0.01) g/min, ranging from 0.2 to 0.6 g/min, and 25.6 (s.e. 0.5) g/kg milk, ranging from 15 to 42 g/kg milk. Estimated dry matter intake was positively correlated with emission rate, which was higher in grazing cows, and negatively correlated with emissions per kg milk and was most significant in PMR-fed cows. Mean CH 4 emission rate increased over the first 9 weeks of lactation and then was steady until week 70. Older cows were associated with lower emissions per minute and per kg milk. Rank correlation for CH 4 emissions among weeks of lactation was generally high. We conclude that CH 4 emissions appear to change across and within lactations, but ranking of a herd remains consistent, which is useful for obtaining CH 4 spot measurements.

Background: In an unparalleled global response, during the COVID-19 pandemic, 90 countries asked 3.9 billion people to stay home. Yet other countries avoided lockdowns and focused on other strategies, like contact tracing. How effective and cost-effective are these strategies? We aimed to provide a comprehensive summary of the evidence on past pandemic controls, with a focus on cost-effectiveness., Methods: Following PRISMA guidelines, MEDLINE (1946 to April week 2, 2020) and EMBASE (1974 to April 17, 2020) were searched using a range of terms related to pandemic control. Articles reporting on the effectiveness or cost-effectiveness of at least one intervention were included., Results: We found 1653 papers; 62 were included. The effectiveness of hand-washing and face masks was supported by randomized trials. These measures were highly cost-effective. For other interventions, only observational and modelling studies were found. They suggested that (1) the most cost-effective interventions are swift contact tracing and case isolation, surveillance networks, protective equipment for healthcare workers, and early vaccination (when available); (2) home quarantines and stockpiling antivirals are less cost-effective; (3) social distancing measures like workplace and school closures are effective but costly, making them the least cost-effective options; (4) combinations are more cost-effective than single interventions; and (5) interventions are more cost-effective when adopted early. For 2009 H1N1 influenza, contact tracing was estimated to be 4363 times more cost-effective than school closure ($2260 vs. $9,860,000 per death prevented)., Conclusions and Contributions: For COVID-19, a cautious interpretation suggests that (1) workplace and school closures are effective but costly, especially when adopted late, and (2) scaling up as early as possible a combination of interventions that includes hand-washing, face masks, ample protective equipment for healthcare workers, and swift contact tracing and case isolation is likely to be the most cost-effective strategy., (© 2022. The Author(s).)

The aim of this study was to investigate the use of signal processing to detect eructation peaks in CH 4 released by cows during robotic milking, and to compare recordings from three gas analysers (Guardian SP and NG, and IRMAX) differing in volume of air sampled and response time. To allow comparison of gas analysers using the signal processing approach, CH 4 in air (parts per million) was measured by each analyser at the same time and continuously every second from the feed bin of a robotic milking station. Peak analysis software was used to extract maximum CH 4 amplitude (ppm) from the concentration signal during each milking. A total of 5512 CH 4 spot measurements were recorded from 65 cows during three consecutive sampling periods. Data were analysed with a linear mixed model including analyser × period, parity, and days in milk as fixed effects, and cow ID as a random effect. In period one, air sampling volume and recorded CH 4 concentration were the same for all analysers. In periods two and three, air sampling volume was increased for IRMAX, resulting in higher CH 4 concentrations recorded by IRMAX and lower concentrations recorded by Guardian SP ( p < 0.001), particularly in period three, but no change in average concentrations measured by Guardian NG across periods. Measurements by Guardian SP and IRMAX had the highest correlation; Guardian SP and NG produced similar repeatability and detected more variation among cows compared with IRMAX. The findings show that signal processing can provide a reliable and accurate means to detect CH 4 eructations from animals when using different gas analysers.

The aim of this study was to assess combining location, acceleration and machine learning technologies to detect estrus in dairy cows. Data were obtained from 12 cows, which were monitored continuously for 12 days. A neck mounted device collected 25,684 records for location and acceleration. Four machine-learning approaches were tested (K-nearest neighbor (KNN), back-propagation neural network (BPNN), linear discriminant analysis (LDA), and classification and regression tree (CART)) to automatically identify cows in estrus from estrus indicators determined by principal component analysis (PCA) of twelve behavioral metrics, which were: duration of standing, duration of lying, duration of walking, duration of feeding, duration of drinking, switching times between activity and lying, steps, displacement, average velocity, walking times, feeding times, and drinking times. The study showed that the neck tag had a static and dynamic positioning accuracy of 0.25 ± 0.06 m and 0.45 ± 0.15 m, respectively. In the 0.5-h, 1-h, and 1.5-h time windows, the machine learning approaches ranged from 73.3 to 99.4% for sensitivity, from 50 to 85.7% for specificity, from 77.8 to 95.8% for precision, from 55.6 to 93.7% for negative predictive value (NPV), from 72.7 to 95.4% for accuracy, and from 78.6 to 97.5% for F1 score. We found that the BPNN algorithm with 0.5-h time window was the best predictor of estrus in dairy cows. Based on these results, the integration of location, acceleration, and machine learning methods can improve dairy cow estrus detection.

Enteric methane (CH ₄ ) is a by-product from fermentation of feed consumed by ruminants, which represents a nutritional loss and is also considered a contributor to climate change. The aim of this research was to use individual animal data from 17 published experiments that included sheep ( n = 288), beef cattle ( n = 71) and dairy cows ( n = 284) to develop an empirical model to describe enteric CH ₄ emissions from both cattle and sheep, and then evaluate the model alongside equations from the literature. Data were obtained from studies in the United Kingdom (UK) and Australia, which measured enteric CH ₄ emissions from individual animals in calorimeters. Animals were either fed solely forage or a mixed ration of forage with a compound feed. The feed intake of sheep was restricted to a maintenance amount of 875 g of DM per day (maintenance level), whereas beef cattle and dairy cows were fed to meet their metabolizable energy (ME) requirement (i.e., production level). A linear mixed model approach was used to develop a multiple linear regression model to predict an individual animal's CH ₄ yield (g CH ₄ /kg dry matter intake) from the composition of its diet. The diet components that had significant effects on CH ₄ yield were digestible organic matter (DOMD), ether extract (EE) (both g/kg DM) and feeding level above maintenance intake: CH ₄ (g/kg DM intake) = 0.046 (±0.001) × DOMD - 0.113 (±0.023) × EE - 2.47 (±0.29) × (feeding level - 1), with concordance correlation coefficient ( CCC ) = 0.655 and RMSPE = 14.0%. The predictive ability of the model developed was as reliable as other models assessed from the literature. These components can be used to predict effects of diet composition on enteric CH ₄ yield from sheep, beef and dairy cattle from feed analysis information., Competing Interests: The authors declare no conflict of interest.

In many animal societies where hierarchies govern access to reproduction, the social rank of individuals is related to their age and weight and slow-growing animals may lose their place in breeding queues to younger 'challengers' that grow faster. The threat of being displaced might be expected to favour the evolution of competitive growth strategies, where individuals increase their own rate of growth in response to increases in the growth of potential rivals. Although growth rates have been shown to vary in relation to changes in the social environment in several vertebrates including fish and mammals, it is not yet known whether individuals increase their growth rates in response to increases in the growth of particular reproductive rivals. Here we show that, in wild Kalahari meerkats (Suricata suricatta), subordinates of both sexes respond to experimentally induced increases in the growth of same-sex rivals by raising their own growth rate and food intake. In addition, when individuals acquire dominant status, they show a secondary period of accelerated growth whose magnitude increases if the difference between their own weight and that of the heaviest subordinate of the same sex in their group is small. Our results show that individuals adjust their growth to the size of their closest competitor and raise the possibility that similar plastic responses to the risk of competition may occur in other social mammals, including domestic animals and primates.

In the past decade, several Bacillus cereus strains have been isolated from otherwise healthy individuals who succumbed to bacterial pneumonia presenting symptoms resembling inhalational anthrax. One strain was indistinguishable from B. cereus G9241, previously cultured from an individual who survived a similar pneumonia-like illness and which was shown to possess a complete set of plasmid-borne anthrax toxin-encoding homologs. The finding that B. cereus G9241 pathogenesis in mice is dependent on pagA1-derived protective antigen (PA) synthesis suggests that an anthrax toxin-based vaccine may be effective against this toxin-encoding B. cereus strain. Dunkin Hartley guinea pigs were immunized with protein- and DNA-based anthrax toxin-based vaccines, immune responses were evaluated and survival rates were calculated after lethal aerosol exposure with B. cereus G9241 spores. Each vaccine induced seroconversion with the protein immunization regimen eliciting significantly higher serum levels of antigen-specific antibodies at the prechallenge time-point compared with the DNA-protein prime-boost immunization schedule. Complete protection against lethal challenge was observed in all groups with a detectable prechallenge serum titer of toxin neutralizing antibodies. For the first time, we demonstrated that the efficacy of fully defined anthrax toxin-based vaccines was protective against lethal B. cereus G9241 aerosol challenge in the guinea pig animal model., (Published 2014. This article is a US Government work and is in the public domain in the USA.)

The aberrant fibrotic and repair responses in the lung are major hallmarks of idiopathic pulmonary fibrosis (IPF). Numerous antifibrotic strategies have been used in the clinic with limited success, raising the possibility that an effective therapeutic strategy in this disease must inhibit fibrosis and promote appropriate lung repair mechanisms. IL-13 represents an attractive target in IPF, but its disease association and mechanism of action remains unknown. In the present study, an overexpression of IL-13 and IL-13 pathway markers was associated with IPF, particularly a rapidly progressive form of this disease. Targeting IL-13 in a humanized experimental model of pulmonary fibrosis using tralokinumab (CAT354) was found to therapeutically block aberrant lung remodeling in this model. However, targeting IL-13 was also found to promote lung repair and to restore epithelial integrity. Thus, targeting IL-13 inhibits fibrotic processes and enhances repair processes in the lung.

Vaccines have evolved for hundreds of years, but all utilize the premise that safely pre-exposing the host to some component of a pathogen allows for enhanced immune recognition, and potential protection from disease, upon encountering the pathogen at a later date. Early vaccination strategies used inactivated or attenuated vaccines, many of which contained toxins and other components that resulted in reactogenicity or risk of reversion to virulence. DNA vaccines supplant many of the issues associated with inactivated or attenuated vaccines, but these vaccines tend to provide weak immunological responses, particularly in primates. DNA Electroporation may prove to be the "missing link" in the evolution of DNA vaccines allowing for enhanced immune responses from DNA vaccination in humans thereby resulting in protection from disease post-pathogen exposure.

Effective multi-agent/multivalent vaccines that confer protection against more than one disease are highly desirable to the patient and to health-care professionals. Electroporation of DNA vaccines, whereby tissues injected with DNA are subjected to localized electrical currents, is an ideal platform technology that achieves protective immune responses to multivalent vaccination. Here, we describe an electroporation-based immunization technique capable of administering a cocktail of DNA vaccinations in vivo. Immune response measurements, including protection from pathogen challenge and induction of antigen-specific antibody responses and cell-mediated immune responses, are also discussed.

We investigate nanosecond photoluminescence processes in colloidal core/shell CdSe/ZnS nanoparticles dissolved in water and found strong sensitivity of luminescence to the solvent state. Several pronounced changes have been observed in the narrow temperature interval near the water melting point. First of all, the luminescence intensity substantially (approximately 50%) increases near the transition. In a large temperature scale, the energy peak of the photoluminescence decreases with temperature due to temperature dependence of the energy gap. Near the melting point, the peak shows N-type dependence with the maximal changes of approximately 30 meV. The line width increases with temperature and also shows N-type dependence near the melting point. The observed effects are associated with the reconstruction of ligands near the ice/water phase transition.

In the present study we have used single-cell RT-PCR in conjunction with electrophysiology to examine the expression and functional properties of metabotropic glutamate receptors (mGluRs) expressed within biochemically identified cholinergic interneurones in the rat striatum. Using single-cell RT-PCR, it was possible to demonstrate the presence of mGluR1, mGluR2, mGluR3, mGluR5 and mGluR7 mRNAs within single cholinergic interneurones. Bath application of the non-selective mGluR agonist (1 S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1 S,3R-ACPD) or the group-I mGluR agonist 3,5-dihydroxyphenylglycine (DHPG) depolarized all cholinergic neurones tested by activation of an inward current at -60 mV. The effects of DHPG were partially inhibited by the mGluR5 selective antagonist 6-methyl-2-(pherazo)-3-pyridinol and by the non-selective group-I antagonist alpha-methyl-4-carboxyphenylglycine but were not mimicked by the group-II and group-III selective mGluR agonists 2-(2,3-dicarboxycyclopropyl)glycine (DCG-IV) and L-2-amino-4-phosphonobutanoate (L-AP4), respectively. Intrastriatal stimulation evoked an excitatory postsynaptic current within cholinergic neurones that was reversibly inhibited by bath application of the group-II and group-III selective mGluR agonists DCG-IV and L-AP4, respectively, via presynaptic actions. In summary, we have identified the mGluRs expressed by striatal cholinergic interneurones and demonstrated that their activation produces modulatory effects via both pre- and postsynaptic mechanisms.