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Goran Ristev,1 Angela C Sipes,1 Bryan Mahoney,2 Jonathan Lipps,1 Gary Chan,3 John C Coffman1 1Department of Anesthesiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA; 2Department of Anesthesiology, Mount Sinai St. Luke’s and Mount Sinai Roosevelt, New York, NY, USA; 3Department of Anesthesiology, Perioperative & Pain Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA Background: The rationale for injection of epidural medications through the needle is to promote sooner onset of pain relief relative to dosing through the epidural catheter given that needle injection can be performed immediately after successful location of the epidural space. Some evidence indicates that dosing medications through the epidural needle results in faster onset and improved quality of epidural anesthesia compared to dosing through the catheter, though these dosing techniques have not been compared in laboring women. This investigation was performed to determine whether dosing medication through the epidural needle improves the quality of analgesia, level of sensory blockade, or onset of pain relief measured from the time of epidural medication injection. Methods: In this double-blinded prospective investigation, healthy term laboring women (n=60) received labor epidural placement upon request. Epidural analgesia was initiated according to the assigned randomization group: 10 mL loading dose (0.125% bupivacaine with fentanyl 2 µg/mL) through either the epidural needle or the catheter, given in 5 mL increments spaced 2 minutes apart. Verbal rating scale (VRS) pain scores (0–10) and pinprick sensory levels were documented to determine the rates of analgesic and sensory blockade onset. Results: No significant differences were observed in onset of analgesia or sensory blockade from the time of injection between study groups. The estimated difference in the rate of pain relief (VRS/minute) was 0.04 (95% CI: −0.01 to 0.11; p=0.109), and the estimated difference in onset of sensory blockade (sensory level/minute) was 0.63 (95% CI: −0.02 to 0.15; p=0.166). The time to VRS ≤3 and level of sensory block 20 minutes after dosing were also similar between groups. No differences in patient satisfaction, or maternal or fetal complications were observed. Conclusion: This investigation observed that epidural needle and catheter injection of medications result in similar onset of analgesia and sensory blockade, quality of labor analgesia, patient satisfaction, and complication rates. Keywords: labor analgesia, epidural needle, epidural catheter, analgesic onset

Small populations or groups of individuals at the edge of a species range can reveal much about a species' niche preference limitations, its demographic history, and its adaptive potential for range expansion or niche shifts. We investigated whether recent sightings of small numbers (n ≤ 12) of beluga whales, Delphinapterus leucas, in Yakutat Bay, Alaska, some 800 km distant from the nearest known population in Cook Inlet, represented a distinct group of whales or temporary extralimital movements from Cook Inlet, and if the former whether they exhibited any genetic consequences of small effective population size. Using remote biopsy sampling ([n.sub.samples]=10), mtDNA sequencing, multi-locus genotyping, and PCR-based gender determination, we found that the Yakutat whales comprised both males and females, exhibited site fidelity across years, were significantly differentiated for mtDNA ([F.sub.st] = 0.54, P < 0.0001) and microsatellite ([F.sub.st] = 0.10, P < 0.0001) loci from the Cook Inlet population, and formed a distinct genetic cluster. Individual assignment methods identified Cook Inlet as the most likely origin of the Yakutat whales when compared to the four other population stocks in the western Nearctic: Bristol Bay, Norton Sound, the Chukchi Sea, and the Beaufort Sea (n = 494), but individual whales had low likelihoods of coming from Cook Inlet relative to whales sampled in that population. We developed a new exclusion-assignment method, GELATo, that estimates the likelihood of a group of whales arising within one, any, or none of a series of reference populations. Using the same five beluga whale reference populations we confirmed the close affinity of Yakutat to Cook Inlet but excluded the Yakutat group as likely immigrants from Cook Inlet (logL= [-68.63.sub.micros] and [-63.06.sub.mtDNA]). These findings, in conjunction with recent beluga whale sightings, including young-of-the-year calves, in Yakutat Bay in all seasons, indicate a small, resident, reproductive group with limited current genetic exchange with Cook Inlet. Lower variation ([H.sub.obs] = 0.580 v. 0.715) at neutral markers, significantly higher relatedness (mean difference in [r.sub.QeullerGt] = 0.410) among and inbreeding (mean difference in F = -0.1 to -0.19) within the Yakutat animals compared to Cook Inlet raise concerns about the loss of genetic diversity over time. While the small size and uncertain history and viability of the Yakutat group creates new management challenges, its location, unique habitat, and persistence up to now can provide insights into the survival of small groups on the warm edge of the species' range and is a testament to the effective stewardship of the local Tlingit community., Introduction Individuals on the frontier of a species' range typically define the geographic limits of suitable conditions for the maintenance of viable populations, but they can also represent the vanguard [...]

Previously published and new U-Pb geochronologic analyses provide 313 zircon and 59 titanite ages that constrain the igneous and cooling history of the Coast Mountains batholith in north-coastal British Columbia. First-order findings are as follows: (1) This segment of the batholith consists of three portions: a western magmatic belt (emplaced into the outboard Alexander and Wrangellia terranes) that was active 177-162 Ma, 157-142 Ma, and 118-100 Ma; an eastern belt (emplaced into the inboard Stikine and Yukon-Tanana terranes) that was active ca. 180-110 Ma; and a 100-50 Ma belt that was emplaced across much of the orogen during and following mid-Cretaceous juxtaposition of outboard and inboard terranes. (2) Magmatism migrated eastward from 120 to 80 (or 60) Ma at a rate of 2.0-2.7 km/Ma, a rate similar to that recorded by the Sierra Nevada batholith. (3) Magmatic flux was quite variable through time, with high (>35-50 [km.sup.3]/Ma per km strike length) flux at 160-140 Ma, 120-78 Ma, and 55-48 Ma, and magmatic lulls at 140-120 Ma and 78-55 Ma. (4) High U/Th values record widespread growth (and/or recrystallization) of metamorphic zircon at 88-76 Ma and 62-52 Ma. (5) U-Pb ages of titanite record rapid cooling of axial portions of the batholith at ca. 55-48 Ma in response to east-side-down motion on regional extensional structures. (6) The magmatic history of this portion of the Coast Mountains batholith is consistent with a tectonic model involving formation of a Late Jurassic-earliest Cretaceous magmatic arc along the northern Cordilleran margin; duplication of this arc system in Early Cretaceous time by >800 km (perhaps 1000-1200 km) of sinistral motion (bringing the northern portion outboard of the southern portion); high-flux magmatism prior to and during orthogonal mid-Cretaceous terrane accretion; low-flux magmatism during Late Cretaceous-Paleocene dextral transpressional motion; and high-flux Eocene magmatism during rapid exhumation in a regime of regional crustal extension.

The purpose of this descriptive census survey was to explore the impact of participation in two integrated, experiential learning programs in a College of Agriculture and Life Sciences. Specific objectives were to determine the influence of these programs on graduates' (a) decisions to enter careers and graduate school, (b) level of skill improvement, (c) career development and decidedness and (d) preparation for careers and graduate school. Graduates believe their experience positively affected development of their skills and abilities and had a positive influence on their career and graduate school aspirations. Graduates report that the programs enhanced their preparation for careers and graduate school by helping them transition from the role of undergraduate student to that of employee or graduate student. Though both programs had positive impacts, there were some significant differences between the two programs, which have different purposes and outcomes. These findings provide further confirmation that experiential learning is an effective way to meet outcomes while using the real-world, hands-on, experiential learning methods that students often prefer. [ABSTRACT FROM AUTHOR]