Productivity of A Resident Giant Canada Goose Flock in Northeastern South Dakota

. A 2-year study (1974-1975) of a resident Canada goose (Branta canadensis maxima) flock is reported. Twenty-four percent of the artificial nest structures (ANS) available were used by nesting geese. Artificial nesting structures, islands, muskrat houses and peninsulas were used by geese as nesting sites. Mean clutch size of completed nests was 5.14 in 1974 and 5.26 in 1975. Mean clutch size was 5.38 on ANS and 4.89 on NNS for the 2-year study. At least one egg hatched in 87 percent of the 283 nests located during the study. Larger clutches had a higher hatchability. Nest success was greater on ANS than NNS (X2 21.001, P\u3c.Ol, 1 d.f.). The main cause of unsuccessful nests was desertion by the nesting pair. Predation and flooding were not major factors in determining nest success. Overall hatching success was 78 percent of 1414 eggs. Nests on ANS had a higher percent hatchability than nests on NNS. Eggs in 213 nests produced 1003 goslings during the study. Mean initial brood size was 4.75 in 1974 and 4.67 in 1975. The relationship between public versus private ownership of land and nest success was significant(X2 6.030, P\u3c.05, 1 d.f.) in 1974 but not significant in 1975. Discriminant analysis of 18 factors associated with nesting indicated that water depth, number of nests on wetland and density of surrounding cover were the most important variables in determining use or nonuse of an ANS

Six-week time series of eddy covariance CO2 flux at Mammoth Mountain, California: performance evaluation and role of meteorological forcing

CO{sub 2} and heat fluxes were measured over a six-week period (09/08/2006 to 10/24/2006) by the eddy covariance (EC) technique at the Horseshoe Lake tree kill (HLTK), Mammoth Mountain, CA, a site with complex terrain and high, spatially heterogeneous CO{sub 2} emission rates. EC CO{sub 2} fluxes ranged from 218 to 3500 g m{sup -2} d{sup -1} (mean = 1346 g m{sup -2} d{sup -1}). Using footprint modeling, EC CO{sub 2} fluxes were compared to CO{sub 2} fluxes measured by the chamber method on a grid repeatedly over a 10-day period. Half-hour EC CO{sub 2} fluxes were moderately correlated (R{sup 2} = 0.42) with chamber fluxes, whereas average-daily EC CO{sub 2} fluxes were well correlated (R{sup 2} = 0.70) with chamber measurements. Average daily EC CO{sub 2} fluxes were correlated with both average daily wind speed and atmospheric pressure; relationships were similar to those observed between chamber CO{sub 2} fluxes and the atmospheric parameters over a comparable time period. Energy balance closure was assessed by statistical regression of EC energy fluxes (sensible and latent heat) against available energy (net radiation, less soil heat flux). While incomplete (R{sup 2} = 0.77 for 1:1 line), the degree of energy balance closure fell within the range observed in many investigations conducted in contrasting ecosystems and climates. Results indicate that despite complexities presented by the HLTK, EC can be reliably used to monitor background variations in volcanic CO{sub 2} fluxes associated with meteorological forcing, and presumably changes related to deeply derived processes such as volcanic activity

Eddy covariance observations of surface leakage during shallow subsurface CO2 releases

We tested the ability of eddy covariance (EC) to detect, locate, and quantify surface CO{sub 2} flux leakage signals within a background ecosystem. For 10 days starting on 07/09/2007, and for seven days starting on 08/03/2007, 0.1 (Release 1) and 0.3 (Release 2) t CO{sub 2}d{sup -1}, respectively, were released from a horizontal well {approx}100 m in length and {approx}2.5 m in depth located in an agricultural field in Bozeman, MT. An EC station measured net CO{sub 2} flux (F{sub c}) from 06/08/2006 to 09/04/2006 (mean and standard deviation = -12.4 and 28.1 g m{sup -2} d{sup -1}, respectively) and from 05/28/2007 to 09/04/2007 (mean and standard deviation = -12.0 and 28.1 g m{sup -2} d{sup -1}, respectively). The Release 2 leakage signal was visible in the F{sub c} time series, whereas the Release 1 signal was difficult to detect within variability of ecosystem fluxes. To improve detection ability, we calculated residual fluxes (F{sub cr}) by subtracting fluxes corresponding to a model for net ecosystem exchange from F{sub c}. F{sub cr} had reduced variability and lacked the negative bias seen in corresponding F{sub c} distributions. Plotting the upper 90th percentile F{sub cr} versus time enhanced the Release 2 leakage signal. However, values measured during Release 1 fell within the variability assumed to be related to unmodeled natural processes. F{sub cr} measurements and corresponding footprint functions were inverted using a least-squares approach to infer the spatial distribution of surface CO{sub 2} fluxes during Release 2. When combined with flux source area evaluation, inversion results roughly located the CO{sub 2} leak, while resolution was insufficient to quantify leakage rate

The capabilities approach and worker wellbeing

Recently, scholars have attempted to apply the capabilities approach, as advanced by Amartya Sen, to the realm of labour. They argue that it provides a philosophical justification for a ‘development’ approach to labour regulation, supports the design of policies that promote workers’ wellbeing and validates the institution of worker participation mechanisms. For labour proponents, this is an exciting prospect. This article argues that despite its promise for expanding workers’ capabilities, certain ambiguities potentially impede the approach’s utility, particularly in developing countries. We suggest ways in which it can be refined and developed to better serve the interests of labour in these contexts, notably by promoting collective and not merely individual capabilities

Linking Taiwan's subcritical Hsuehshan Range topography and foreland basin architecture

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95204/1/tect2249.pd

Southern San Andreas-San Jacinto fault system slip rates estimated from earthquake cycle models constrained by GPS and interferometric synthetic aperture radar observations

We use ground geodetic and interferometric synthetic aperture radar satellite observations across the southern San Andreas (SAF)-San Jacinto (SJF) fault systems to constrain their slip rates and the viscosity structure of the lower crust and upper mantle on the basis of periodic earthquake cycle, Maxwell viscoelastic, finite element models. Key questions for this system are the SAF and SJF slip rates, the slip partitioning between the two main branches of the SJF, and the dip of the SAF. The best-fitting models generally have a high-viscosity lower crust (η = 10^(21) Pa s) overlying a lower-viscosity upper mantle (η = 10^(19) Pa s). We find considerable trade-offs between the relative time into the current earthquake cycle of the San Jacinto fault and the upper mantle viscosity. With reasonable assumptions for the relative time in the earthquake cycle, the partition of slip is fairly robust at around 24–26 mm/a for the San Jacinto fault system and 16–18 mm/a for the San Andreas fault. Models for two subprofiles across the SAF-SJF systems suggest that slip may transfer from the western (Coyote Creek) branch to the eastern (Clark-Superstition hills) branch of the SJF from NW to SE. Across the entire system our best-fitting model gives slip rates of 2 ± 3, 12 ± 9, 12 ± 9, and 17 ± 3 mm/a for the Elsinore, Coyote Creek, Clark, and San Andreas faults, respectively, where the large uncertainties in the slip rates for the SJF branches reflect the large uncertainty in the slip rate partitioning within the SJF system

Discovery of Inhibitors of Leishmania β-1,2-Mannosyltransferases Using a Click-Chemistry-Derived Guanosine Monophosphate Library

Leishmania spp. are a medically important group of protozoan parasites that synthesize a novel intracellular carbohydrate reserve polymer termed mannogen. Mannogen is a soluble homopolymer of β-1,2-linked mannose residues that accumulates in the major pathogenic stages in the sandfly vector and mammalian host. While several steps in mannogen biosynthesis have been defined, none of the enzymes have been isolated or characterized. We report the development of a simple assay for the GDP-mannose–dependent β-1,2-mannosyltransferases involved in mannogen synthesis. This assay utilizes octyl α-d-mannopyranoside to prime the formation of short mannogen oligomers up to 5 mannose residues. This assay was used to screen a focussed library of 44 GMP-triazole adducts for inhibitors. Several compounds provided effective inhibition of mannogen β-1,2-mannosyltransferases in a cell-free membrane preparation. This assay and inhibitor compounds will be useful for dissecting the role of different mannosyltransferases in regulating de novo biosynthesis and elongation reactions in mannogen metabolism

Disease-associated CAG·CTG triplet repeats expand rapidly in non-dividing mouse cells, but cell cycle arrest is insufficient to drive expansion

Artículo científico -- Universidad de Costa Rica, Instituto de Investigaciones en Salud. 2014Genetically unstable expanded CAG·CTG trinucleotide repeats are causal in a number of human disorders, including Huntington disease and myotonic dystrophy type 1. It is still widely assumed that DNA polymerase slippage during replication plays an important role in the accumulation of expansions. Nevertheless, somatic mosaicism correlates poorly with the proliferative capacity of the tissue and rates of cell turnover, suggesting that expansions can occur in the absence of replication. We monitored CAG·CTG repeat instability in transgenicmouse cells arrested by chemical or genetic manipulation of the cell cycle and generated unequivocal evidence for the continuous accumulation of repeat expansions in non-dividing cells. Importantly, the rates of expansion in non-dividing cells were at least as high as those of proliferating cells. These data are consistent with amajor role for cell division-independent expansion in generating somatic mosaicism in vivo. Although expansions can accrue in non-dividing cells, we also show that cell cycle arrest is not sufficient to drive instability, implicating other factors as the key regulators of tissue-specific instability. Our data reveal that de novo expansion events are not limited to S-phase and further support a cell divisionindependent mutational pathway.Universidad de Costa Rica. Instituto de Investigaciones en SaludInstitute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, GlasgowParis Descartes-Sorbonne Paris Cité UniversityUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA

Association analysis of ACE and ACTN3 in Elite Caucasian and East Asian Swimmers

Purpose: Polymorphic variation in the angiotensin-converting enzyme (ACE) and α-actinin-3 (ACTN3) genes has been reported to be associated with endurance and/or power-related human performance. Our aim was to investigate whether polymorphisms in ACE and ACTN3 are associated with elite swimmer status in Caucasian and East Asian populations. Methods: ACE I/D and ACTN3 R577X genotyping was carried out for 200 elite Caucasian swimmers from European, Commonwealth, Russian, and American cohorts (short and middle distance, ≤400 m, n = 130; long distance, >400 m, n = 70) and 326 elite Japanese and Taiwanese swimmers (short distance, ≤100 m, n = 166; middle distance, 200-400 m, n = 160). Genetic associations were evaluated by logistic regression and other tests accommodating multiple testing adjustment. Results: ACE I/D was associated with swimmer status in Caucasians, with the D allele being overrepresented in short-and-middle-distance swimmers under both additive and I-allele-dominant models (permutation test P = 0.003 and P = 0.0005, respectively). ACE I/D was also associated with swimmer status in East Asians. In this group, however, the I allele was overrepresented in the short-distance swimmer group (permutation test P = 0.041 and P = 0.0098 under the additive and the D-allele-dominant models, respectively). ACTN3 R577X was not significantly associated with swimmer status in either Caucasians or East Asians. Conclusions: ACE I/D associations were observed in these elite swimmer cohorts, with different risk alleles responsible for the associations in swimmers of different ethnicities. The functional ACTN3 R577X polymorphism did not show any significant association with elite swimmer status, despite numerous previous reports of associations with "power/sprint" performance in other sports