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Estimating sex ratios is important for understanding population demographics. Here, we present a direct comparison of paired sex ratio estimates from visual field surveys and molecular sex identification using scat in sexually dimorphic Steller sea lions (Eumetopias jubatus). For this purpose, we designed novel qPCR Taqman gene expression assays to determine sex from scat of both Steller and California (Zalophus californianus) sea lions targeting the zinc-finger X-linked gene (ZFX) and sex-determining region Y gene (SRY). The assay pair was validated using scat samples from California sea lions of known sex with 100% success rate of signal amplification. Our assays yielded a 94.1% success rate in identifying sea lion sex from field-collected scats. In addition, the sex ratio determined via molecular analysis was closely correlated to the adult male and adult female proportions observed at the haul-out site for each month scat samples and demographic counts were collected in tandem. While visual counts cannot determine the sex of juvenile sea lions, scat collections are assumed to represent all age classes present at the haulout, suggesting that the juvenile sex ratios likely mirrored the adult sex ratio. The protocol described here could be implemented to identify the sex of Steller and California sea lions from their feces in free-ranging populations in other non-invasive, scat-based studies. Further, the concordance with visual observations suggests that molecular sex identification from scat collected at haul-outs is a robust methodology in sea lions and possibly in other pinniped species that lack distinctive sexual dimorphism. [ABSTRACT FROM AUTHOR]

Biodegradable polymers for food applications have emerged as a sustainable alternative to reduce plastic waste. In this work, compostable films based on blends of poly(ε-caprolactone) (PCL) and thermoplastic gliadins (TPG) were developed for packaging applications. Firstly, gliadins were extracted from wheat gluten and plasticized with glycerol. Then, PCL/TPG films were prepared by cast-extrusion processing at pilot scale and samples were characterized in terms of their structural, morphological, thermal, mechanical, barrier and optical properties. The addition of TPG increased the glass transition temperature (Tg) of PCL, reduced the oxygen permeability at 0% and 50% relative humidity values, and improved the seal strength properties of the films, having a minimal effect on the thermal stability, transparency, and the high stretchability characteristic of PCL. On the other hand, the presence of gliadins led to more water sensitive materials, resulting in a slight increase in the water vapor permeability. Finally, the home-compostability assessment of the films revealed that the presence of gliadins accelerated the aerobic biodegradation and the disintegration with respect to pristine PCL film, thus, showing the potential interest of the developed materials for sustainable packaging applications. [ABSTRACT FROM AUTHOR]

Pinniped predation on commercially and ecologically important prey has been a source of conflict for centuries. In the Salish Sea, harbor seals (Phoca vitulina) are suspected of impeding the recovery of culturally and ecologically critical Pacific salmon (Oncorhynchus spp.). In Fall 2020, a novel deterrent called Targeted Acoustic Startle Technology (TAST) was deployed at Whatcom Creek to deter harbor seals from preying on fall runs of hatchery chum (O. keta) and Chinook (O. tshawytscha) salmon in Bellingham, Washington, USA. Field observations were conducted in 2020 to compare the presence and foraging success of individual harbor seals across sound exposure (TAST-on) and control (TAST-off) conditions. Observations conducted the previous (2019) and following (2021) years were used to compare the effects observed in 2020 to two control years. Using photo-identification, individual seals were associated with foraging successes across all 3 years of the study. Generalized linear mixed models showed a significant 45.6% reduction in the duration (min) individuals remained at the creek with TAST on, and a significant 43.8% reduction in the overall foraging success of individuals. However, the observed effect of TAST varied across individual seals. Seals that were observed regularly within one season were more likely to return the year after, regardless of TAST treatment. Generalized linear models showed interannual variation in the number of seals present and salmon consumed. However, the effect of TAST in 2020 was greater than the observed variation across years. Our analyses suggest TAST can be an effective tool for managing pinniped predation, although alternate strategies such as deploying TAST longer-term and using multi-unit setups to increase coverage could help strengthen its effects. Future studies should further examine the individual variability found in this study. [ABSTRACT FROM AUTHOR]

The complexities of trophic dynamics complicate the management of predator populations. Targeted culling campaigns are one management strategy meant to control predation for the benefit of the prey population. In these campaigns, individual predators are often considered "rogue" based on visitation rates to the site of concern. This definition assumes that all predators impact prey equally. However, individual variability in foraging success may compromise this assumption. To examine this hypothesis, we studied harbor seals preying on adult salmonids during the 2014–2019 fall runs in Whatcom Creek, Bellingham, Washington, USA, and recorded visitation rate and foraging success of individual seals from photographs and field observations. We then used Generalized Linear Mixed-Effects Models to model individual foraging success. Models including harbor seal identity better explained foraging success than models based on visitation rate alone. We concluded that considering intraspecific variability and classifying "rogue individuals" based on foraging success is a more accurate protocol for managing predator populations than relying solely on visitation rate of the predators. [ABSTRACT FROM AUTHOR]

Marine trophic ecology data are in high demand as natural resource agencies increasingly adopt ecosystem-based management strategies that account for complex species interactions. Harbour seal (Phoca vitulina) diet data are of particular interest because the species is an abundant predator in the northeast Pacific Ocean and Salish Sea ecosystem that consumes Pacific salmon (Oncorhynchus spp.). A multi-agency effort was therefore undertaken to produce harbour seal diet data on an ecosystem scale using, 1) a standardized set of scat collection and analysis methods, and 2) a newly developed DNA metabarcoding diet analysis technique designed to identify prey species and quantify their relative proportions in seal diets. The DNA-based dataset described herein contains records from 4,625 harbour seal scats representing 52 haulout sites, 7 years, 12 calendar months, and a total of 11,641 prey identifications. Prey morphological hard parts analyses were conducted alongside, resulting in corresponding hard parts data for 92% of the scat DNA samples. A custom-built prey DNA sequence database containing 201 species (192 fishes, 9 cephalopods) is also provided. Measurement(s) diet Technology Type(s) DNA metabarcoding diet analysis Sample Characteristic - Organism Phoca vitulina Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.19077809 [ABSTRACT FROM AUTHOR]

Despite calls for more attention to the preparation of those who prepare teachers, there have been few examples of institutionally sanctioned and structured learning opportunities created to equip faculty with the knowledge and skills necessary to become effective teacher educators. In this paper, we describe a cross-disciplinary and collaborative initiative that involves shadowing of colleagues as a means of supporting the professional learning of science teacher educators. We illustrate the unique affordance of this model and highlight our professional learning across multiple dimensions: cognitive, practical, relational, and emotional. We illustrate how shadowing can support the learning of faculty at different career stages and from different disciplinary backgrounds and entry points to teacher education through a series of vignettes of shadowing in a variety of course contexts. Finally, we offer considerations for the transferability of our model to other institutions and contexts, and how further research conducted in the context of shadowing could help deepen our understanding of the knowledge base of science teacher educators and how this knowledge is developed. [ABSTRACT FROM AUTHOR]

A comparison of DOT-ELISA and Standard-ELISA was made for detection of Vibrio cholerae toxin in culture supernatants of bacteria isolated from human and environmental samples. A total of 293 supernatants were tested in a double blind assay. A correlation of 100 % was obtained between both techniques. The cholera toxin was found in 20 Inaba and 3 Ogawa strains. Positive samples were from seafood (17 samples), potable water (1 sample) and sewage (5 samples). The DOT-ELISA was useful as the standard-ELISA to confirm the presence of cholera toxin in the environmental samples. [ABSTRACT FROM AUTHOR]

Uruguay is currently undergoing a gradual process of inclusion of wind energy in its matrix of electric power generation. In this context, a computational tool has been developed to predict the electrical power that will be injected into the grid. The tool is based on the Weather Research and Forecasting (WRF) numerical model, which is the performance bottleneck of the application. For this reason, and in line with several successful efforts of other researchers, this article presents advances in porting the WRF to GPU. In particular, we present the implementation of sintb and bdy_interp1 routines on GPU and the integration of these routines with previous efforts from other authors. The speedup values obtained for the newly ported routines on a Nvidia GeForce GTX 480 GPU are up to $$33.9\times $$ when compared with the sequential WRF and $$9.2\times $$ when compared with the four-threaded WRF. The integration of the newly ported routines along with previous works produces a reduction of more than a 30 % in the total runtime of the multi-core four-threaded WRF and of more than a 50 % in the single-threaded version. [ABSTRACT FROM AUTHOR]

A comparison was made of the effects of levamisole, the bacterial fractions of Staphylococcus, and Freund's adjuvant on the immunization of rats with the excretory and secretory antigens of Trichinella spiralis muscle larvae. Wistar rats were immunized with the antigen and a saline solution, levamisole (LV), Staphylococcus (ST), or Freund's adjuvant (FA). After immunization, rats were infected, and the parasite burden at muscular phase was calculated for each group. Levels of IgG1 and IgG2 antibodies, as well as levels of two cytokines, IL-4 and IFN-γ, were evaluated during the immunization and postinfection periods. Differences were found in the kinetics of antibody production between groups ( p < 0.01). In all cases, there was reactivity with the main 45-, 50-, and 55-kDa antigens of Trichinella muscle larvae. Immunization with FA and ST enhanced the production of IgG1, but only FA showed a significant increase in the production of IFN-γ ( p < 0.01), resulting in 86 % protection against the infection. In contrast, only 60-70 % protection was attained in the ST and LV groups ( p < 0.01). These data support the idea that levamisole and Staphylococcus can be used as adjuvant to enhance the humoral response and, at the same time, demonstrate that IFN-γ could be involved in protection against Trichinella. [ABSTRACT FROM AUTHOR]

Porous platinum thin films were prepared by thermal decomposition at temperatures from 25 to 675 °C of platinum oxide films deposited by a pulsed reactive sputtering technique. The samples’ chemistry and structure were investigated by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and x-ray absorption near edge structure (XANES), showing that the decomposition of the oxide begins as low as 400 °C and follows a sigmoidal trend with increasing annealing temperature. In the XRD spectra, only an amorphous-like signature was observed for temperatures below 575 °C, while Pt 4f XPS showed that the deposited oxide was a mixture of PtO2 and PtO. Pt-L3 edge XANES and Pt 4f XPS spectra showed that the Pt concentration and electronic structure are predominant for temperatures equal to or above 575 °C. The morphologies of the films were investigated by the area-perimeter method from atomic force microscopy and scanning electron microscopy (SEM) images, indicating that the surfaces exhibit a combination of Euclidian and fractal characteristics. Moreover, the thermal evolution of these characteristics indicates the agglomeration of the grains in the film as observed by SEM. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented that discusses a study that analyzes the local structure and bonds of silicon in TiSiN and AlCrSiN by X-ray diffraction (XRD) and X-ray absorption near edge structure (XANES).

Severe acute liver failure, even when transient, must be treated by transplantation and lifelong immune suppression. Treatment could be improved by bioartificial liver (BAL) support, but this approach is hindered by a shortage of human hepatocytes. To generate an alternative source of cells for BAL support, we differentiated mouse embryonic stem (ES) cells into hepatocytes by coculture with a combination of human liver nonparenchymal cell lines and fibroblast growth factor-2, human activin-A and hepatocyte growth factor. Functional hepatocytes were isolated using albumin promoter–based cell sorting. ES cell–derived hepatocytes expressed liver-specific genes, secreted albumin and metabolized ammonia, lidocaine and diazepam. Treatment of 90% hepatectomized mice with a subcutaneously implanted BAL seeded with ES cell–derived hepatocytes or primary hepatocytes improved liver function and prolonged survival, whereas treatment with a BAL seeded with control cells did not. After functioning in the BAL, ES cell–derived hepatocytes developed characteristics nearly identical to those of primary hepatocytes. [ABSTRACT FROM AUTHOR]

The high-temperature oxidation resistance of laser-surface-alloyed Incoloy 800H with Al has been investigated. Several samples have been exposed to 1000°C in air and subsequently analyzed by optical microscopy, SEM, and electron microprobe X-ray fluorescence spectroscopy in order to determine their microstructure and composition. The results show that the laser-treated materials have a considerably higher oxidation resistance than the nontreated materials due to the formation of an Al-rich layer close to the surface, which acts as a barrier against oxygen diffusion into the bulk. [ABSTRACT FROM AUTHOR]

A correction to the article "Reversal of mouse hepatic failure using an implanted liver-assist device containing ES cell-derived hepatocytes" that was published in the November 5, 2006 issue is presented.