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The Transportable Array in south-central Alaska spans several subduction zone features: backarc, forearc and volcanic arc, making it an ideal tool to study subduction zone anisotropy. Shear wave splitting analysis of 157 local earthquakes of m b ≥ 3.0 that occurred between 2014 and 2019 yields 210 high-quality measurements at 23 stations. Splitting delay times (δ t) are generally small (δ t ≈ 0.3 s), increasing with distance from the trench. Arc-parallel fast directions, ϕ, are only seen in the forearc, but rotate to arc-perpendicular ϕ in the backarc. Observed ϕ values generally do not parallel teleseismic SKS splitting results, implying that the latter is sensitive primarily to subslab mantle flow, not mantle wedge dynamics. The forearc local-earthquake signal likely originates from anisotropic serpentinite in fractures atop the subducting Pacific Plate, with possible additional signal coming from fractures in the North American crust. Mantle wedge corner flow, potentially with additional arc-perpendicular anisotropy in the subducting slab, explains backarc anisotropy. [ABSTRACT FROM AUTHOR]

Alaska provides an ideal tectonic setting for investigating the interaction between subduction and asthenospheric flow. Within the span of a few hundred kilometers along strike, the geometry of the subducting Pacific plate varies significantly and terminates in a sharp edge. Furthermore, the region documents a transition from subduction along the Aleutian Arc to strike‐slip faulting along the Pacific Northwest. To better understand mantle interactions within this subduction zone, we conduct an SKS shear‐wave splitting analysis on passive‐source seismic data collected between 2011 and 2018 at 239 broadband seismometers, including those from the Transportable Array. Anisotropic fast directions in the east of our study area parallel the Queen Charlotte and Fairweather transform faults, suggesting that the ongoing development of lithospheric anisotropy dominates the results there. However, our observed delay times (δt = 1–1.5 s) obtained across the study region may also imply an asthenospheric contribution to the splitting pattern. Our splitting observations exhibit slab‐parallel fast directions northwest of the trench and a rotation of fast directions around the northeastern slab edge. These observations suggest the presence of toroidal asthenospheric flow around the edge of the downgoing Pacific plate. We suggest that Wrangell Volcanic Field volcanism might be caused by mantle upwelling associated with this flow. Splitting observations closer to the trench can be explained by fossil anisotropy within the downgoing Pacific‐Yakutat plate combined with entrained subslab mantle. The geometry of the slab, including its variable dip and its abrupt eastern edge, thus plays an important role in governing mantle flow beneath Alaska. Key Points: Fast directions parallel major transform faults and Yakutat terrane subduction, suggesting a lithospheric source of anisotropyFast directions wrapping around the slab edge and high delay times suggest a toroidal asthenospheric flow as another cause of anisotropyVariability in slab geometry exerts first‐order control over mantle flow at the edge of the Alaskan margin [ABSTRACT FROM AUTHOR]

Introduction: The next generation of wound dressings will actively participate in the wound healing process, helping the body to heal itself. For deep and/or chronic wounds a dermal scaffold is often required prior to the application of a skin graft or other therapy that encourages re-epithelialisation and the restoration of the barrier function. The aim of this study was to determine if electrospinning and plasma polymerisation could be used to generate a scaffold that would support fibroblast growth and extracellular deposition. Methods: A totally synthetic electrospun dermal replacement was produced coated with an allylamine plasma polymer and its impact upon cellular processes assessed in vitro. Results: The scaffold encouraged increased adhesion and rapid migration of human dermal fibroblasts into the scaffold. Fibroblasts rapidly proliferated to populate the scaffold and deposited significantly more collagen I on scaffolds coated with the allylamine plasma polymer than the uncoated poly(lactic acid) scaffold or scaffolds coated with other plasma polymers (acrylic acid or 1,7' octadiene). Conclusions: Electrospinning and plasma polymerisation are both versatile and widely used techniques that are also suitable for large-scale manufacture of scaffolds. These properties increase the potential of the scaffold to include its use as a cell delivery device for the delivery of fibroblasts, including their associated extracellular matrix and mitogens to chronic wounds. [ABSTRACT FROM AUTHOR]

Presents a technique for obtaining highly smooth focused laser beams. Strategy employed in the study; Implementation consideration for smoothing by spectral dispersion; Simulation results.

Breeds of larger mature size tend to grow more rapidly and be older when attaining a given level of fatness. Hereford, Limousin, and Piedmontese are of approximately equal mature size and yet may vary in body composition at a given degree of maturity. However, direct comparisons among these three breeds were not found. Therefore, the objective of this research was to compare Hereford, Limousin, and Piedmontese progenies for economically important traits. Crossbred cows were bred to Hereford (n = 23), Limousin (n = 24), or Piedmontese (n = 24) sires. Male calves were either left intact or castrated at approximately 2 mo of age. Calves remained with their dams until weaning at an average age of 179 d. Male calves were then individually fed a growing ration until they reached 386 kg and then fed a finishing ration either 90 or 132 d. They were then slaughtered at a commercial abattoir and carcass data were collected. Female calves were group-fed and used to examine nutritional effects on age at puberty. Data were analyzed using REML and linear contrasts among the breed-of-sire effects evaluated. Hereford-sired calves had shorter gestation periods and weighed less at birth than either Limousin- or Piedmontese-sired calves. Calving difficulty of Hereford- and Limousin-sired calves was less than that of Piedmontese-sired calves. Limousin-sired calves tended to grow more rapidly than Hereford-sired calves. By the finishing phase, Limousin- and Hereford-sired calves had greater average daily gains than Piedmontese-sired calves. Differences in dry matter intake among breeds of sire were relatively small. Differences in carcass weight, longissimus muscle area, fat depth, and percentage kidney, pelvic, and heart fat resulted in a clear stratification of USDA yield grade between breeds of sire. Differences in percentage primal cuts were similar to those for USDA yield grade. Hereford-sired calves had more marbling than progeny of Limousin or Piedmontese sires. However, the force necessary to shear cores from steaks of Piedmontese-sired calves was less than for progeny of Limousin or Hereford sires. Hereford- and Piedmontese-sired heifers were younger at puberty than Limousin-sired heifers. Within breeds of similar mature size and growth rate, ample variation exists in age at puberty and body composition at an approximately equal degree of maturity. Key Words: Beef Cattle, Breed Differences, Carcass Composition, Growth, Puberty

The objective was to test the efficacy of an intravaginal progesterone insert and injection of [PGF.sub.2[Beta]], for synchronizing estrus and shortening the interval to pregnancy in cattle. Cattle were assigned to one of three treatments before a 31-d breeding period that employed artificial insemination. Control cattle were not treated, and treated cattle were administered [PGF.sub.2[Beta]] or an intravaginal progesterone-releasing insert (CIDR) for 7 d and treated with [PGF.sub.2[Beta]] on d 6. The treatments were applied in one of three experiments that involved postpartum beef cows (Exp. 1; n = 851; 56 [+ or -] 0.6 d postpartum), beef heifers (Exp. 2; n = 724; 442.5 [+ or -] 2.8 d of age), and dairy heifers (Exp. 3; n = 260; 443.2 [+ or -] 4.5 d of age). Luteal activity before treatment was determined for individual cattle based on blood progesterone concentrations. In Exp. 1, there was a greater incidence of estrus during the first 3 d of the breeding period in CIDR+[PGF.sub.2[Beta]]-treated cows compared with [PGF.sub.2[Beta]]-treated or control cows (15, 33, and 59% for control, [PGF.sub.2[Beta]], and CIDR+[PGF.sub.2[Beta]], respectively; P [is less than] 0.001). The improved estrous response led to an increase in pregnancy rate during the 3-d period (7, 22, and 36% for control, [PGF.sub.2[Beta]], and CIDR+[PGF.sub.2[Beta]], respectively; P [is less than] 0.001) and tended to improve pregnancy rate for the 31-d breeding period for cows treated with CIDR+[PGF.sub.2[Beta]], (50, 55, and 58% for control, [PGF.sub.2[Beta]], and CIDR+[PGF.sub.2[Beta]], respectively, P = 0.10). Improvements in rates of estrus and pregnancy after CIDR+[PGF.sub.2[Beta]] were also observed in beef heifers. Presence of luteal activity before the treatment period affected synchronization and pregnancy rates because anestrous cows (Exp. 1) or prepubertal heifers (Exp. 2) had lesser synchronization rates and pregnancy rates during the first 3 d of the breeding period as well as during the entire 31-d breeding period. The [PGF.sub.2[Beta]] and CIDR+[PGF.sub.2[Beta]] but not the control treatments were evaluated in dairy heifers (Exp. 3). The CIDR+[PGF.sub.2[Beta]]-treated heifers had a greater incidence of estrus (84%) during the first 3 d of the breeding period compared with the [PGF.sub.2[Beta]]-treated heifers (57%), but pregnancy rates during the first 3 d or during the 31-d breeding period were not improved for CIDR+[PGF.sub.2[Beta]] compared with [PGF.sub.2[Beta]]-treated heifers. In summary, the concurrent treatment of CIDR and [PGF.sub.2[Beta]] improved synchronization rates relative to [PGF.sub.2[Beta]] alone or control. Improved estrus synchrony led to greater pregnancy rates for beef cows and beef heifers but failed to improve pregnancy rates for dairy heifers. Key Words: Estrus, Progesterone, Prostaglandins, Synchronization

A 2-yr study was conducted to evaluate the interactions of castration, feeding length, and dietary CP on growth and carcass characteristics of male cattle (bulls and steers) that vary in expression of muscular hypertrophy. Crossbred cows were bred by AI to Hereford, Limousin, or Piedmontese bulls, which represented genotypes with normal, moderate, and hyper-muscularity, respectively, but with similar mature weights. Male calves (131 in yr 1 and 120 in yr 2) were placed in pens with individual electronic feeding gates. Calves were fed growing diets until they reached 386 kg BW and then were individually switched to finishing diets for 90 or 132 d. Interactions were observed among sire breed, gender, and feeding length on carcass composition. Bulls were more efficient than steers in producing live weight gain. Length of finishing period accounted for a larger source of variation than gender for weight characteristics, whereas gender was the larger source of variation for carcass composition. Concentration or degradability of dietary CP influenced rate of gain from weaning to 386 kg. Interactions resulting from varying management on carcass characteristics among calves of different sire breeds indicate that unique strategies may be beneficial for the production of meat from these breeds. Key Words: Breeds, Carcass Quality, Cattle, Growth, Muscle weight

Prepubertal [F.sub.1] heifers (n = 246; from crossbred dams bred to either Hereford [H], Limousin [L], or Piedmontese [P] sires) were fed 1.9% (LF) or 4.4% (HF) dietary fat from 254 [+ or -] 4 d of age until they reached puberty or the breeding season started. Safflower seeds (37% oil with 79% linoleic acid) were the added fat source. Blood samples and backfat thickness measurements were obtained from 60 randomly selected heifers representing the sire breeds and diets studied. In addition, five H-sired heifers from both diets were serially bled at 28-d intervals. Total gain, ADG, body condition score, and backfat thickness were affected by sire breed (P [is less than] 0.001) but not diet. Backfat thickness was affected (P [is less than] 0.01) by the diet x time on feed interaction. Diet did not affect pubertal age (P [is greater than] 0.10) but tended (P = 0.08) to affect the percentage of heifers pubertal by the beginning of breeding (June 4). Sire breed effects on puberty age at beginning of breeding, percentage pubertal at the beginning of breeding, and puberty age during the entire study were all highly significant. The effect of the diet x sire breed interaction on percentage of heifers pubertal at beginning of breeding (P [is less than] 0.05) was 74.4 vs 76.3% in H-sired, 69.8 vs 60.5% in L-sired, and 76.2 vs 97.6% in P-sired heifers (LF vs HF, respectively). Number of AI services per pregnancy and final pregnancy percentage were not affected by diet or the diet x sire breed interaction. Diet affected progesterone (P [is less than] 0.05) and cholesterol (P [is less than] 0.001) concentrations, and sire breed tended to affect (P = 0.06) cholesterol concentrations. The effect of the diet x time on feed interaction on cholesterol concentrations was highly significant. There were no effects of diet or sample period on insulin or growth hormone concentrations in serially collected blood samples. We conclude that effects of supplemental dietary fat may be breed-dependent and hypothesize that a feeding period of approximately 60 d duration may be more appropriate than the 162 d used in this study. Key Words: Beef Breeds, Dietary Fat, Puberty, Safflower