Genome sequence of Christensenella minuta DSM 22607T

Obesity influences and is influenced by the human gut microbiome. Here, we present the genome of Christensenella minuta, a highly heritable bacterial species which has been found to be strongly associated with obesity through an unknown biological mechanism. This novel genome provides a valuable resource for future obesity therapeutic studies

Ergonomics Case Study: EA-6B Aircraft Maintainer

Keeping our military aircraft mechanics healthy is essential for the defense of the country. To better understand the conditions which on-duty aircraft maintainers face, A series of ergonometric evaluations were performed on a retired United States Marine Corps mechanic as he simulated tasks performed while maintaining EA-6B Prowler aircraft. Four tasks were evaluated with either the Rapid Entire Body Assessment (REBA) tool, or the Washington State Risk Assessment Checklist (WAC). The tasks were grouped as being either strenuous or repetitive. The strenuous tasks involved high physical exertion. Repetitive tasks were less demanding but needed to be performed many times during a mechanic’s shift. Two strenuous tasks were examined, those being the replacement of engine Constant Speed Drive (CSD) units and engine access doors. The two repetitive tasks analyzed were the inspections of both cockpits and engine compressor blades. All tasks analyzed with the REBA scored within its two highest risk categories, and the weight of the CSD exceeded that recommended by the WAC by over 30lbs. Mechanics who perform these tasks should be aided by using mechanized jacks to lift heavy objects, while aspects of the repetitive tasks should be automated reduce their cumulative strain

Exploring alternative methods for population surveillance

Swine disease surveillance is of great importance to the swine industry in order to raise and provide healthy animal populations. In order to insure timely disease intervention for optimal animal health, surveillance methods and sampling options need to be readily available. Many of our diagnostic sample collections are based on individual animal samples, i.e. serum, blood swabs, nasal swabs, etc. These individual sample diagnostics are then commonly used to infer information on the population level. In order to understand population status from a collection of individual samples, diagnostic and sampling methods require evaluation. As reviewed in Chapter 1, the pooling of individual samples is commonly place in various fields of veterinary medicine. In order to properly utilize this diagnostic strategy all the factors that affect pooling results need to be understood. Pooled diagnostics are influenced by the type of analyte, stage of infection, sample dilution, matrix components, the prevalence of disease, and laboratory differences. In order to attain accurate diagnostics and to properly pooling interpret results, these factors must be accounted for. In continuation of the study of disease surveillance methods, the objective of the first research paper (Chapter 2) was to evaluate different sample collection techniques for the early detection Porcine Respiratory and Reproductive Syndrome Virus (PRRSV) in a boar stud population based in individual sampling techniques. Diagnostic specimens analyzed in this study included serum, oral fluid, blood swabs, frothy saliva, and semen. Semen samples were centrifuged and the seminal supernatant and cell fractions were tested separately. All samples were randomly ordered and tested for PRRSV by real-time quantitative reverse-transcriptase polymerase chain reaction (rRT-PCR) and PRRSV antibody ELISA. No statistically significant differences were found between serum, blood swabs, and oral fluids in the onset of detection but numerical differences did exist. The objective of the second study (Chapter 3) was to evaluate if the oral fluid training and collection methods used for the boars in Chapter 2 could be applied to individually housed commercial sows. This study also analyzed the diagnostic reproducibility of PCR and ELISA results from the same animals. To achieve this, oral fluid sample collection was attempted on 513 individually housed; mixed parity sows naive to oral fluid collection. Oral fluid collection was attempted for each animal on two successive days under the same collection conditions. Successful paired oral fluid samples were randomly selected, randomized for submission, and tested by PRRSV PCR and oral fluid ELISA for anti-PRRSV antibodies. Younger sows and the re-sampling of animals were positively associated with collection success and diagnostic results collected on two successive days were correlated

Genomic introgression mapping of field-derived multiple-anthelmintic resistance in Teladorsagia circumcincta

Preventive chemotherapy has long been practiced against nematode parasites of livestock, leading to widespread drug resistance, and is increasingly being adopted for eradication of human parasitic nematodes even though it is similarly likely to lead to drug resistance. Given that the genetic architecture of resistance is poorly understood for any nematode, we have analyzed multidrug resistant Teladorsagia circumcincta, a major parasite of sheep, as a model for analysis of resistance selection. We introgressed a field-derived multiresistant genotype into a partially inbred susceptible genetic background (through repeated backcrossing and drug selection) and performed genome-wide scans in the backcross progeny and drug-selected F2 populations to identify the major genes responsible for the multidrug resistance. We identified variation linking candidate resistance genes to each drug class. Putative mechanisms included target site polymorphism, changes in likely regulatory regions and copy number variation in efflux transporters. This work elucidates the genetic architecture of multiple anthelmintic resistance in a parasitic nematode for the first time and establishes a framework for future studies of anthelmintic resistance in nematode parasites of humans

Construction costs, chemical composition and payback time of high- and low-irradiance leaves

The effect of irradiance on leaf construction costs, chemical composition, and on the payback time of leaves was investigated. To enable more generalized conclusions, three different systems were studied: top and the most-shaded leaves of 10 adult tree species in a European mixed forest, top leaves of sub-dominant trees of two evergreen species growing in small gaps or below the canopy in an Amazonian rainforest, and plants of six herbaceous and four woody species grown hydroponically at low or high irradiance in growth cabinets. Daily photon irradiance varied 3-6-fold between low- and high-light leaves. Specific leaf area (SLA) was 30-130% higher at low light. Construction costs, on the other hand, were 1-5% lower for low-irradiance leaves, mainly because low-irradiance leaves had lower concentrations of soluble phenolics. Photosynthetic capacity and respiration, expressed per unit leaf mass, were hardly different for the low- and high-light leaves. Estimates of payback times of the high-irradiance leaves ranged from 2-4 d in the growth cabinets, to 15-20 d for the adult tree species in the European forest. Low-irradiance leaves had payback times that were 2-3 times larger, ranging from 4 d in the growth cabinets to 20-80 d at the most shaded part of the canopy of the mixed forest. In all cases, estimated payback times were less than half the life span of the leaves, suggesting that even at time-integrated irradiances lower than 5% of the total seasonal value, investment in leaves is still fruitful from a carbon-economy point of view. A sensitivity analysis showed that increased SLA of low-irradiance leaves was the main factor constraining payback times. Acclimation in the other five factors determining payback time, namely construction costs, photosynthetic capacity per unit leaf mass, respiration per unit leaf mass, apparent quantum yield, and curvature of the photosynthetic light-response-curve, were unimportant when the observed variation in each factor was examine

The identification of small molecule inhibitors with anthelmintic activities that target conserved proteins among ruminant gastrointestinal nematodes

Gastrointestinal nematode (GIN) infections are a major concern for the ruminant industry worldwide and result in significant production losses. Naturally occurring polyparasitism and increasing drug resistance that potentiate disease outcomes are observed among the most prevalent GINs of veterinary importance. Within the five major taxonomic clades, clade Va represents a group of GINs that predominantly affect the abomasum or small intestine of ruminants. However, the development of effective broad-spectrum anthelmintics against ruminant clade Va GINs has been challenged by a lack of comprehensive druggable genome resources. Here, we first assembled draft genomes for three clade Va species

Data-Driven Distributionally Robust Electric Vehicle Balancing for Autonomous Mobility-on-Demand Systems under Demand and Supply Uncertainties

Electric vehicles (EVs) are being rapidly adopted due to their economic and societal benefits. Autonomous mobility-on-demand (AMoD) systems also embrace this trend. However, the long charging time and high recharging frequency of EVs pose challenges to efficiently managing EV AMoD systems. The complicated dynamic charging and mobility process of EV AMoD systems makes the demand and supply uncertainties significant when designing vehicle balancing algorithms. In this work, we design a data-driven distributionally robust optimization (DRO) approach to balance EVs for both the mobility service and the charging process. The optimization goal is to minimize the worst-case expected cost under both passenger mobility demand uncertainties and EV supply uncertainties. We then propose a novel distributional uncertainty sets construction algorithm that guarantees the produced parameters are contained in desired confidence regions with a given probability. To solve the proposed DRO AMoD EV balancing problem, we derive an equivalent computationally tractable convex optimization problem. Based on real-world EV data of a taxi system, we show that with our solution the average total balancing cost is reduced by 14.49%, and the average mobility fairness and charging fairness are improved by 15.78% and 34.51%, respectively, compared to solutions that do not consider uncertainties.Comment: 16 page

Factors affecting the recovery of Mexican wolves in the Southwest United States

Recovering and maintaining large carnivore populations is a global conservation challenge that requires better knowledge of the factors affecting their populations, particularly in shared landscapes (i.e. non-protected areas where people occupy and or utilize the land). The Mexican wolf (Canis lupus baileyi) is an endangered wolf subspecies being recovered on shared landscapes in the Southwest United States and Mexico. We used data from the U.S. program to model population growth, evaluate the impact of management removal and illegal killing relative to other demographic factors, and test hypotheses about factors influencing rates of management removal and illegal killing. From 1998 to 2019, the population growth averaged 12% per year. Rates of natural reproduction, illegal killing and other mortality remained consistent over the 22 years; while releases, translocations and management removals varied markedly between two time periods, phase 1:1998–2007 and phase 2:2008–2019. The number of wolves removed for conflict management was higher during phase 1 (average ~ 13 per year, rate = 24.8%) than phase 2 (average of ~5 per year, rate = 5.2%). This decrease in management removal resulted in the wolf population resuming growth after a period of population stagnation. Two factors influenced this decrease, a change in policy regarding removal of wolves (stronger modelling support) and a decrease in the number of captive-reared adult wolves released into the wild (weaker modelling support). Illegal mortality was relatively constant across both phases, but after the decrease in management removal, illegal mortality became the most important factor (relative importance shifted from 28.2% to 50.1%). Illegal mortality was positively correlated with rates of reintroduction and translocation of wolves and negatively correlated with the rate of management removal. 6. Synthesis and applications. Using management removal to reduce human–carnivore conflict can have negative population impacts if not used judiciously. Recovering and maintaining carnivore populations in shared landscapes may require greater tolerance of conflict and more emphasis on effective conflict prevention strategies and compensation programs for affected stakeholders