Downer cows: a reanalysis of an old data set.

CAUL Read and Publish Agreement.AIMS: To compare the performance of two predictive models for the survival of downer cows. METHODS: The first model had been developed in 1987 using a dataset containing missing values, while the second, new model was developed on the same dataset but using modern data imputation and analytical methods. Missing data were imputed using multiple imputation by chained equations and a logistic regression model fitted to the imputed data, with survival or not as the outcome variable. The predictive ability of the model built on the imputed data was contrasted with the original prognostic model by testing them both on a second smaller but complete data set, collected contemporaneously with the development of the original model but from a different region of New Zealand. Sensitivity, specificity, accuracy, and cut point for the two models were calculated. RESULTS: The original 1987 model had a slightly higher accuracy than that of the new one with a sensitivity of 0.85 (95% CI = 0.72-0.94) and a specificity of 0.82 (95% CI = 0.7-0.91), using a cut point for the probability of survival = 0.313. CONCLUSIONS: The original prognostic formula published by Clark et al. in 1987 performed as well as a modern model built on an imputed data set. CLINICAL RELEVANCE: The use of a prognostic test based on the Clark model should remain an important part of the clinical examination of downer cows by New Zealand veterinarians.Abbreviations: AUC: Area under the curve; AST: Aspartate transaminase activity; CK: Creatine phosphokinase activity; GAM: Generalised additive model; NSAID: Non-steroidal-anti-inflammatory drugs; PCV: Packed cell volume.Publishe

Side-by-Side Thermal Tests of Modular Offices: A Validation Study of the STEM Method

Two modular office units were tested at the National Renewable Energy Laboratory (NREL) to establish each unit's thermal performance. The two units were nearly identical in appearance, but one was built with structural insulating panels (SIP), and the other was built using standard frame construction. The primary objective of these tests was to compare the thermal performance of buildings using SIP and standard frame construction. Both units were tested under carefully controlled steady-state conditions in the NREL large-scale environmental enclosure. They were then moved outdoors where Short-Term Energy Monitoring (STEM) tests were performed, and long-term heating and cooling energy use was measured. A secondary objective was to evaluate the accuracy of the NREL STEM method by comparing the results of outdoor STEM tests to steady-state indoor test results. STEM is a method developed by NREL to determine key thermal parameters of a building in-situ, based on a 3-day test sequence. The indoor test facility also provided the opportunity to investigate the phenomenon of infiltration heat recovery in a real building, under carefully controlled conditions, to evaluate the stability of the concentration decay method of tracer gas-based infiltration monitoring, and to compare the blower-door method with the tracer-gas technique in determining infiltration.This project was a cooperative effort with the Structural Insulated Panel Association, the Modular Building Institute, All-American Modular (AAM, the manufacturer of the units), and GE Capitol (the owner of the units). Richard Harmon, the president of AAM, requested NREL's assistance in exploring the feasibility of converting his manufacturing process to SIP construction. His engineering staff needed to assess which comfort and energy benefits might be associated with this new technology. AAM manufactured the two units, and NREL tested the modules for 8 months

Postreproductive killer whale grandmothers improve the survival of their grandoffspring

Abstract under embarg

A long postreproductive life span is a shared trait among genetically distinct killer whale populations.

The extended female postreproductive life span found in humans and some toothed whales remains an evolutionary puzzle. Theory predicts demographic patterns resulting in increased female relatedness with age (kinship dynamics) can select for a prolonged postreproductive life span due to the combined costs of intergenerational reproductive conflict and benefits of late-life helping. Here, we test this prediction using >40 years of longitudinal demographic data from the sympatric yet genetically distinct killer whale ecotypes: resident and Bigg's killer whales. The female relatedness with age is predicted to increase in both ecotypes, but with a less steep increase in Bigg's due to their different social structure. Here, we show that there is a significant postreproductive life span in both ecotypes with >30% of adult female years being lived as postreproductive, supporting the general prediction that an increase in local relatedness with age predisposes the evolution of a postreproductive life span. Differences in the magnitude of kinship dynamics however did not influence the timing or duration of the postreproductive life span with females in both ecotypes terminating reproduction before their mid-40s followed by an expected postreproductive period of about 20 years. Our results highlight the important role of kinship dynamics in the evolution of a long postreproductive life span in long-lived mammals, while further implying that the timing of menopause may be a robust trait that is persistent despite substantial variation in demographic patterns among populations

Mixture models as a method for comparative sociality: social networks and demographic change in resident killer whales

In studies of social behaviour, social bonds are usually inferred from rates of interaction or association. This approach has revealed many important insights into the proximate formation and ultimate function of animal social structures. However, it remains challenging to compare social structure between systems or time-points because extrinsic factors, such as sampling methodology, can also influence the observed rate of association. As a consequence of these methodological challenges, it is difficult to analyse how patterns of social association change with demographic processes, such as the death of key social partners. Here we develop and illustrate the use of binomial mixture models to quantitatively compare patterns of social association between networks. We then use this method to investigate how patterns of social preferences in killer whales respond to demographic change. Resident killer whales are bisexually philopatric, and both sexes stay in close association with their mother in adulthood. We show that mothers and daughters show reduced social association after the birth of the daughter’s first offspring, but not after the birth of an offspring to the mother. We also show that whales whose mother is dead associate more with their opposite sex siblings and with their grandmother than whales whose mother is alive. Our work demonstrates the utility of using mixture models to compare social preferences between networks and between species. We also highlight other potential uses of this method such as to identify strong social bonds in animal populations

Simulating the effect of high-intensity sound on cetaceans: Modeling approach and a case study for Cuvier’s beaked whale ( Ziphius cavirostris

A finite element model is formulated to study the steady-state vibration response of the anatomy of a whale (Cetacea) submerged in seawater. The anatomy was reconstructed from a combination of two-dimensional (2D) computed tomography (CT) scan images, identification of Hounsfield units with tissue types, and mapping of mechanical properties. A partial differential equation model describes the motion of the tissues within a Lagrangean framework. The computational model was applied to the study of the response of the tissues within the head of a neonate Cuvier's beaked whale Ziphius cavirostris. The characteristics of the sound stimulus was a continuous wave excitation at 3500 Hz and 180 dB re: 1 mu Pa received level, incident as a plane wave. We model the beaked whale tissues embedded within a volume of seawater. To account for the finite dimensions of the computational volume, we increased the damping for viscous shear stresses within the water volume, in an attempt to reduce the contribution of waves reflected from the boundaries of the computational box. The mechanical response of the tissues was simulated including: strain amplitude; dissipated power; and pressure. The tissues are not likely to suffer direct mechanical or thermal damage, within the range of parameters tested. (c) 2006 Acoustical Society of America

Movements and Population Structure of Humpback Whales in the North Pacific

Despite the extensive use of photographic identification methods to investigate humpback whales in the North Pacific, few quantitative analyses have been conducted. We report on a comprehensive analysis of interchange in the North Pacific among three wintering regions (Mexico, Hawaii, and Japan) each with two to three subareas, and feeding areas that extended from southern California to the Aleutian Islands. Of the 6,413 identification photographs of humpback whales obtained by 16 independent research groups between 1990 and 1993 and examined for this study, 3,650 photographs were determined to be of suitable quality. A total of 1,241 matches was found by two independent matching teams, identifying 2,712 unique whales in the sample (seen one to five times). Site fidelity was greatest at feeding areas where there was a high rate of resightings in the same area in different years and a low rate of interchange among different areas. Migrations between winter regions and feeding areas did not follow a simple pattern, although highest match rates were found for whales that moved between Hawaii and southeastern Alaska, and between mainland and Baja Mexico and California. Interchange among subareas of the three primary wintering regions was extensive for Hawaii, variable (depending on subareas) for Mexico, and low for Japan and reflected the relative distances among subareas. Interchange among these primary wintering regions was rare. This study provides the first quantitative assessment of the migratory structure of humpback whales in the entire North Pacific basin

High Effectiveness of Broad Access Direct-Acting Antiviral Therapy for Hepatitis C in an Australian Real-World Cohort: The REACH-C Study

Australia was one of the first countries with unrestricted access to government subsidized direct-acting antiviral (DAA) therapy for adults with chronic hepatitis C virus. This study assessed real-world DAA treatment outcomes across a diverse range of Australian clinical services and evaluated factors associated with successful treatment and loss to follow-up. Real-world Effectiveness of Antiviral therapy in Chronic Hepatitis C (REACH-C) consisted a national observational cohort of 96 clinical services including specialist clinics and less traditional settings such as general practice. Data were obtained on consecutive individuals who commenced DAAs from March 2016 to June 2019. Effectiveness was assessed by sustained virological response ≥12 weeks following treatment (SVR) using intention-to-treat (ITT) and per-protocol (PP) analyses. Within REACH-C, 10,843 individuals initiated DAAs (male 69%; ≥50 years 52%; cirrhosis 22%). SVR data were available in 85% (9,174 of 10,843). SVR was 81% (8,750 of 10,843) by ITT and 95% (8,750 of 9,174) by PP. High SVR (≥92%) was observed across all service types and participant characteristics. Male gender (adjusted odds ratio [aOR] 0.56, 95% confidence interval [CI] 0.43-0.72), cirrhosis (aOR 0.52, 95% CI 0.41-0.64), recent injecting drug use (IDU; aOR 0.64, 95% CI 0.46-0.91) and previous DAA treatment (aOR 0.50, 95% CI 0.28-0.90) decreased the likelihood of achieving SVR. Multiple factors modified the likelihood of loss to follow-up including IDU ± opioid agonist therapy (OAT; IDU only: aOR 1.75, 95% CI 1.44-2.11; IDU + OAT: aOR 1.39, 95% CI 1.11-1.74; OAT only, aOR 1.36; 95% CI 1.13-1.68) and age (aOR 0.97, 95% CI 0.97-0.98). Conclusion: Treatment response was high in a diverse population and through a broad range of services following universal access to DAA therapy. Loss to follow-up presents a real-world challenge. Younger people who inject drugs were more likely to disengage from care, requiring innovative strategies to retain them in follow-up

Does spatial locative comprehension predict landmark-based navigation?

In the present study we investigated the role of spatial locative comprehension in learning and retrieving pathways when landmarks were available and when they were absent in a sample of typically developing 6- to 11-year-old children. Our results show that the more proficient children are in understanding spatial locatives the more they are able to learn pathways, retrieve them after a delay and represent them on a map when landmarks are present in the environment. These findings suggest that spatial language is crucial when individuals rely on sequences of landmarks to drive their navigation towards a given goal but that it is not involved when navigational representations based on the geometrical shape of the environment or the coding of body movements are sufficient for memorizing and recalling short pathways