Additional Evidence Against Radio-handicapping of Northern Bobwhites

The validity of radio-telemetry to produce reliable information (e.g., survival estimates) has recently been challenged. Radio-telemetry is a widely used technique in studies of numerous species, therefore, concerns regarding potential bias in these estimates warrant further investigation. As such, and as part of a larger study, we investigated 3 aspects of potential radio-bias: 1) variation in survival distributions among treatment (newly radio-tagged) and control (previously radio-tagged) groups; 2) proportion of trapped animals censored during the traditional 7-day censor period; and 3) ramifications to cause-specific mortality through estimation of harvest rate. Kaplan-Meier survival, based on 30-day post trapping, was similar between treatment (n = 901) and control (n = 293) bobwhites for all but 1 of 8 trapping sessions during 2000-2004. In this case, treatment bobwhites (0.970, SE = 0.015) had higher survival than control birds (0.878, SE = 0.042). We determined the effect of censoring relative to sample size was inconsequential for our analysis because the proportion of bobwhites (18 out of 1,350; 0.013) meeting the criteria for censoring, i.e., dying during the first 7 days, was minimal. Censoring of these data influenced survival estimates by an average of only 0.016 (SE = 0.004; range: 0.00 - 0.04). We evaluated harvest rate by comparing first year recovery rates of banded verses radio-tagged birds during thirteen hunting seasons occurring between 1992 and 2005. Annual recovery rate was not different (P \u3c 0.05) for banded birds and radio-tagged birds where harvest averaged 6.68% (range 3.3 - 11.7) and 6.65% (range 3.4 - 11.1), respectively. These findings are consistent with previous research demonstrating that radio-telemetry can provide reliable demographic information. However, we recommend that future researchers test for these potential effects among their data before making biological inferences

Bosonization in d=2 from finite chiral determinants with a Gauss decomposition

We show how to bosonize two-dimensional non-abelian models using finite chiral determinants calculated from a Gauss decomposition. The calculation is quite straightforward and hardly more involved than for the abelian case. In particular, the counterterm $A\bar A$, which is normally motivated from gauge invariance and then added by hand, appears naturally in this approach.Comment: 4 pages, Revte

Northern Bobwhite Demographic and Population Response Following an Intensive Habitat Modification to an Agricultural Landscape

Northern Bobwhite (Colinus virginianus) populations have been declining throughout most of their endemic range due to numerous factors (e.g., increased urbanization, predators); however, changing land-use practices have proved most detrimental to bobwhites. In parts of the southeastern USA, small-scale farming has been replaced by large-scale center-pivot irrigated fields and this has exacerbated habitat loss. Despite these trends, bobwhite populations in the Southeast have remained stable or increased on many areas employing intensive habitat management regimes, substantiating the importance of appropriate habitat management for long-term bobwhite persistence. In effort to reverse one such decline, we intensively modified a center-pivot, agriculture dominated landscape to benefit bobwhites by creating new habitat and improving existing habitat. Techniques utilized to modify this landscape were: establishment of linear habitats (field borders and buffer strips); planting longleaf pines; and management of existing habitat via prescribed burning and timber management. During 1998-2001, we monitored bobwhite (n = 498) demographics and population response following annual habitat restoration and management using radio-telemetry and fall abundance estimation (i.e., covey call-counts). Average survival during over-winter (0.4698, SE = 0.0721), breeding (0.3561, SE = 0 .0667) and annual (0.1673, SE = 0.0411) time-periods were higher than those reported for other agriculture studies and similar to those of intensively managed, “plantation” habitats. Bobwhite coveys and broods used newly developed longleaf pine, linear habitats (e.g. field borders/hedgerows), and managed woodlands. Further, nest site selection was commonly associated with these novel habitat types. As a result of the positive demographic response to habitat modification, bobwhite abundance also improved during the study. Consequently, we surmised that modification of agricultural landscapes may improve habitat quality and quantity for bobwhites and subsequently help to increase demographic rates and bobwhite abundance

Summer Male Call Index Relative to Nesting Chronology and Autumn Density of the Northern Bobwhite

We studied breeding season male call counts and breeding behavior of the Northern Bobwhite (Colinus virginianus) to determine the relationship between male calling activity and nesting chronology. Additionally, we examined the relationship between breeding season call counts and fall population size. Standardized call count routes were conducted on 6 different sites located in southwest Georgia and north Florida during the breeding season months (1 Apr - 31 Sep) in 2001 and 2002. An information theoretic approach was used to evaluate a set of 7 candidate, linear-mixed models describing breeding season calling of bobwhite males. Of the candidate models, the model in which call counts depended on year and a quadratic effect of the number of incubating hens was the best approximating model, suggesting that the percentage of incubating hens had the greatest influence on activity of calling males. We also used multiple linear regression models to predict autumn northern bobwhite abundance from mean numbers of calling male bobwhites detected during the breeding season. Peaks in male calling activity occurring during June and July demonstrated a strong relationship (R2 = 0.987) with autumn population size, suggesting breeding season call counts were useful indices of autumn bobwhite abundance

Survival and Causes of Mortality for Northern Bobwhites in the Southeastern USA

Long-term studies are imperative to increase our knowledge of northern bobwhite (Colinus virginianus; hereafter bobwhite) demographics. During 1992-2005, we determined survival and cause-specific mortality of bobwhites on 10 study areas in southern Georgia and eastern Alabama, USA.We radio-tagged 7,105 bobwhites and determined 49 annual (Oct-Sep) and 110 seasonal survival estimates to examine spatial and temporal variation in survival. Annual survival for all sites and years combined averaged 0.196 (SE = 0.011) and ranged from 0.08 to 0.40. Over-winter (Oct - Mar) seasonal survival estimates (n = 51) averaged 0.541 (SE = 0.019) and ranged between 0.25 and 0.82, while breeding season (Apr-Sep) survival estimates (n = 59) averaged 0.352 (SE= 0.013) and ranged between 0.13 and 0.59. Over-winter mortality (n = 1,473) of known fates was attributed to avian predation (0.572 ± 0.040), mammal predation (0.265 ± 0.044), harvest (0.156 ± 0.028), snake predation (0.001 ± 0.004) and other (0.005 0.002). Breeding season mortality (n = 2138) was attributed to avian predation (0.613 ± 0.026), mammal predation (0.339 0.049), snake predation (0.037 ± 0.006) and other (0.011 ± 0.004). These over-winter survival estimates were higher than previously published estimates for populations on unmanaged lands and/or heavily harvested populations. On managed lands in the Southeast, bobwhite annual survival rates derived from radio-telemetry were reasonable and provided useful information for management and research

Estimation of the additive and dominance variances in South African Landrace pigs

The objective of this study was to estimate dominance variance for number born alive (NBA), 21- day litter weight (LWT21) and interval between parities (FI) in South African Landrace pigs. A total of 26223 NBA, 21335 LWT21 and 16370 FI records were analysed. Bayesian analysis via Gibbs sampling was used to estimate variance components and genetic parameters were calculated from posterior distributions. Estimates of additive genetic variance were 0.669, 43.46 d2 and 9.02 kg2 for NBA, FI and LWT21, respectively. Corresponding estimates of dominance variance were 0.439, 123.68 d2 and 2.52 kg2, respectively. Dominance effects were important for NBA and FI. Permanent environmental effects were significant for FI and LWT21. It may be beneficial to evaluate non-additive genetic merit of individuals and families in addition to their transmitting abilities. A breeding program that capitalizes on non-additive genetic merit may be desirable. Keywords: Non-additive genetic effects, Bayesian analysis, genetic parameters South African Journal of Animal Science Vol. 36 (4) 2006: pp. 261-26

Transcription-associated breaks in Xeroderma Pigmentosum group D cells from patients with combined features of Xeroderma Pigmentosum and Cockayne Syndrome

Defects in the XPD gene can result in several clinical phenotypes, including xeroderma pigmentosum (XP), trichothiodystrophy, and, less frequently, the combined phenotype of XP and Cockayne syndrome (XP-D/CS). We previously showed that in cells from two XP-D/CS patients, breaks were introduced into cellular DNA on exposure to UV damage, but these breaks were not at the sites of the damage. In the present work, we show that three further XP-D/CS patients show the same peculiar breakage phenomenon. We show that these breaks can be visualized inside the cells by immunofluorescence using antibodies to either gamma-H2AX or poly-ADP-ribose and that they can be generated by the introduction of plasmids harboring methylation or oxidative damage as well as by UV photoproducts. Inhibition of RNA polymerase II transcription by four different inhibitors dramatically reduced the number of UV-induced breaks. Furthermore, the breaks were dependent on the nucleotide excision repair (NER) machinery. These data are consistent with our hypothesis that the NER machinery introduces the breaks at sites of transcription initiation. During transcription in UV-irradiated XP-D/CS cells, phosphorylation of the carboxy-terminal domain of RNA polymerase II occurred normally, but the elongating form of the polymerase remained blocked at lesions and was eventually degraded

Imaging findings in 14 dogs and 3 cats with lobar emphysema

Abstract Background Lobar emphysema in dogs and cats is caused by bronchial collapse during expiration and subsequent air trapping. Congenital causes such as bronchial cartilage defects or acquired causes such as compressive neoplastic lesions have been reported. Morbidity results from hyperinflation of the affected lung lobe and compression of adjacent thoracic structures. Objective To describe patient characteristics and imaging findings in dogs and cats with lobar emphysema. Animals Fourteen dogs and 3 cats with lobar emphysema diagnosed by imaging findings were retrospectively identified from veterinary referral hospital populations over a 10‐year period. Methods Cases that included thoracic radiography, thoracic computed tomography (CT), or both were included. All images were reviewed by a European College of Veterinary Diagnostic Imaging diplomate. Relevant case information included signalment, clinical findings, treatment, and histopathology where available. Results Ten of 17 (59%) patients were presented for evaluation of dyspnea and 6 (35%) for coughing. Eleven (65%) patients were <3 years of age. The right middle lung lobe was affected in 12 cases (71%) and multiple lobes were affected in 7 cases (41%). Congenital lobar emphysema was suspected in 14 cases (82%). Conclusion and Clinical Importance Lung lobe hyperinflation, atelectasis of nonaffected lung lobes, mediastinal shift, and thoracic wall and diaphragmatic wall deformation were common findings. Lobar or multilobar emphysema should be considered in patients with dyspnea or coughing, particularly younger patients. Although radiography is useful, CT provides better detail. In older patients, acquired causes of bronchial compression should be considered

Long-term efficacy and safety of the microsomal triglyceride transfer protein inhibitor lomitapide in patients with homozygous familial hypercholesterolemia

Homozygous familial hypercholesterolemia is a genetic disorder characterized by low-density lipoprotein (LDL)-receptor dysfunction, markedly elevated levels of LDL-cholesterol (LDL-C) and premature atherosclerosis. Patients are often poorly responsive to conventional lipid-lowering therapies that upregulate LDL-receptor expression

Tuberculosis research in South Africa over the past 30 years: From bench to bedside

The South African Medical Research Council Centre for Tuberculosis Research has a rich history of high-impact research that has influenced our understating of this hyper-epidemic which is further exacerbated by the emergence and spread of drug-resistant forms of the disease. This review aims to summarise the past 30 years of research conducted in the Centre which has influenced the way that tuberculosis (TB) is diagnosed and treated. The review includes the development of new technologies for rapid screening of people with probable TB and the repurposing of human diagnostics for wildlife conservation