Controls on the composition and lability of dissolved organic matter in Siberia's Kolyma River basin

High-latitude northern rivers export globally significant quantities of dissolved organic carbon (DOC) to the Arctic Ocean. Climate change, and its associated impacts on hydrology and potential mobilization of ancient organic matter from permafrost, is likely to modify the flux, composition, and thus biogeochemical cycling and fate of exported DOC in the Arctic. This study examined DOC concentration and the composition of dissolved organic matter (DOM) across the hydrograph in Siberia's Kolyma River, with a particular focus on the spring freshet period when the majority of the annual DOC load is exported. The composition of DOM within the Kolyma basin was characterized using absorbance-derived measurements (absorbance coefficienta330, specific UV absorbance (SUVA254), and spectral slope ratio SR) and fluorescence spectroscopy (fluorescence index and excitation-emission matrices (EEMs)), including parallel factor analyses of EEMs. Increased surface runoff during the spring freshet led to DOM optical properties indicative of terrestrial soil inputs with high humic-like fluorescence, SUVA254, and low SRand fluorescence index (FI). Under-ice waters, in contrast, displayed opposing trends in optical properties representing less aromatic, lower molecular weight DOM. We demonstrate that substantial losses of DOC can occur via biological (∼30% over 28 days) and photochemical pathways (>29% over 14 days), particularly in samples collected during the spring freshet. The emerging view is therefore that of a more dynamic and labile carbon pool than previously thought, where DOM composition plays a fundamental role in controlling the fate and removal of DOC at a pan-Arctic scale

ACVIM consensus statement on the treatment of immune-mediated hemolytic anemia in dogs

Immune‐mediated hemolytic anemia (IMHA) causes severe anemia in dogs and is associated with considerable morbidity and mortality. Treatment with various immunosuppressive and antithrombotic drugs has been described anecdotally and in previous studies, but little consensus exists among veterinarians as to the optimal regimen to employ and maintain after diagnosis of the disease. To address this inconsistency and provide evidence‐based guidelines for treatment of IMHA in dogs, we identified and extracted data from studies published in the veterinary literature. We developed a novel tool for evaluation of evidence quality, using it to assess study design, diagnostic criteria, explanation of treatment regimens, and validity of statistical methods. In combination with our clinical experience and comparable guidelines for humans afflicted with autoimmune hemolytic anemia, we used the conclusions of this process to make a set of clinical recommendations regarding treatment of IMHA in dogs, which we refined subsequently by conducting several iterations of Delphi review. Additionally, we considered emerging treatments for IMHA in dogs and highlighted areas deserving of future research. Comments were solicited from several professional bodies to maximize clinical applicability before the recommendations were submitted for publication. The resulting document is intended to provide clinical guidelines for management of IMHA in dogs. These guidelines should be implemented pragmatically, with consideration of animal, owner, and veterinary factors that may vary among cases

The early effects of external and internal strategies on working memory updating training

The mechanisms underlying working memory training remain unclear, but one possibility is that the typically limited transfer effects of this training reflect adoption of successful task-specific strategies. Our pre-registered randomized controlled trial (N = 116) studied the early effects of externally given vs. internally generated strategies in an updating task (n-back) over a 5-day period with a single 30-minute training session. Three groups were employed: n-back training with strategy instruction (n = 40), n-back training without strategy instruction (n = 37), and passive controls (n = 39). We found that both external and internal strategy use was associated with significantly higher posttest performance on the trained n-back task, and that training with n-back strategy instruction yielded positive transfer on untrained n-back tasks, resembling the transfer pattern typically seen after the ordinary uninstructed 4-6-week working memory training. In the uninstructed participants, the level of detail and type of internally generated n-back strategies at posttest was significantly related to their posttest n-back performance. Our results support the view that adoption of task-specific strategies plays an important role in working memory training outcomes, and that strategy-based effects are apparent right at the start of training

Human epididymis protein 4 antigen-autoantibody complexes complement cancer antigen 125 for detecting early-stage ovarian cancer

Background: Early detection of ovarian cancer could significantly improve patient outcomes. Cancer antigen 125 (CA 125) is elevated in sera from approximately 60% of patients with early‐stage (I/II) disease. Sensitivity might be improved through the combination of CA 125 with other biomarkers. Among potential biomarkers, antigen‐autoantibody (Ag‐AAb) complexes have received relatively little attention. / Methods: Luminex‐based immunoassays were used to measure human epididymis protein 4 (HE4), anti‐HE4 autoantibody, and HE4 Ag‐AAb complexes in sera from patients with early‐ (n = 73) and late‐stage ovarian cancers (n = 49) at the time of diagnosis and from asymptomatic women with (n = 15) or without ovarian cancer (n = 212) enrolled in the Normal Risk Ovarian Cancer Screening Study. / Results: At 98% specificity for healthy, asymptomatic women, 7% of patients with early‐stage (I/II) ovarian cancer and 4% of patients with late‐stage (III/IV) disease had elevated levels of HE4 autoantibody, whereas elevated levels of HE4 Ag‐AAb complexes were detected in sera from 38% of early‐stage cases and 31% of late‐stage cases. Complementarity was observed in receiver operating characteristic (ROC) curves between HE4 Ag‐AAb complexes and CA 125 levels in early‐stage ovarian cancer (P < .001). CA 125 detected 63% of cases, and a combination of CA 125 and HE4 Ag‐AAb complexes detected 81%. Complementarity was also observed in ROC curves for an independent validation set with 69 early‐stage patients (P = .039). HE4 Ag‐AAb complexes were detected in serial preclinical serum samples from women destined to develop ovarian cancer: they correlated with CA 125 but did not provide a lead time. / Conclusions: HE4 Ag‐AAb complexes could complement CA 125 in detecting a higher fraction of early‐stage ovarian cancers

The Ursinus Weekly, April 18, 1949

Council adopts petitions for \u2749 coed elections • Junior men to elect annual prom queen • Black-faced belles plan initial debut for minstrel frolic • Organizations seek support of students in worthy projects • Y commission lists letters, trip, talk in year\u27s activities • Sororities plan party for frosh; Movie, social to highlight affair • FTA elects Heist to presidency for \u2749-\u2750 schedule of activities • What do you demand of your ideal man? • Bruins drop 4-3 decision in ten inning ball game • Five sports events fill week\u27s roster • Sixteen get awards for winter sports • Students find appeal in Curtain Club actshttps://digitalcommons.ursinus.edu/weekly/1614/thumbnail.jp

Anatomical correlates of cursoriality are compromised by body size and propensity to burrow in a group of small mammals (Lagomorpha)

Highly cursorial animals are specialised for fast, sustained running via specific morphological adaptations, notably including changes in limb segment length and mechanical advantage. Members of the order Lagomorpha (hares, rabbits and pikas) vary in cursorial ability; hares are generally highly cursorial, rabbits more frequently saltate, and pikas predominantly trot. Previous investigations of lagomorphs have identified anatomical trends correlated with this ‘cursoriality gradient’, however, the phylogenetic sampling of such investigations has been limited to three American species, namely the American pika (Ochotona princeps), brush rabbit (Sylvilagus bachmani), and black-tailed jackrabbit (Lepus californicus). Here, we expand the phylogenetic sample and body size range by including novel data from Australian samples of the European rabbit (Oryctolagus cuniculus) and European hare (L. europaeus), alongside unpublished data on the Eastern cottontail (S. floridanus). X-ray Computed Tomography and digital landmarking were used to capture proportions within the appendicular skeleton of ~ 40 specimens of each European species. In doubling the number of species studied, we find the previously-identified morphological gradients associated with cursorial behaviour are complicated when evaluated in the larger sample. The relative length and joint velocity of limbs was found to be lower than predicted in European rabbits and hares. Furthermore, we present a novel assessment of morphological integration in the lagomorph appendicular skeleton, finding between-limb covariation patterns that are generally similar to those of other mammals. Broadly, these results suggest cursoriality is only one of many selective forces driving lagomorph skeletal evolution, with variations in body size and fossoriality potentially having measurable impacts.Ellen M. Martin, Jesse W. Young, Connie D. Fellmann, Brian Kraatz, Emma Sherrat

Glacier runoff influences biogeochemistry and resource availabilityin coastal temperate rainforest streams: Implications for juvenile salmon growth

Meltwater contributions to watersheds are shrinking as glaciers disappear, altering theflow, temperature, andbiogeochemistry of freshwaters. A potential consequence of this landscape change is that streamflow patternswithin glacierized watersheds will become more homogenous, potentially altering the capacity of watersheds tosupport Pacific salmon. To assess heterogeneity in stream habitat quality for juvenile salmon in a watershed inthe Alaska Coast Mountains, we collected organic matter and invertebrate drift and measured streamwater phys-ical and biogeochemical properties over the main runoff season in two adjacent tributaries, one fed mainly byrain and the other partially by glacier ice/snowmelt. We then used bioenergetic modeling to evaluate how tem-poral patterns in water temperature and invertebrate drift in each tributary influence juvenile salmon growthpotential. Across the study period, average invertebrate drift concentrations were similar in non-glacierizedMontana (0.33 mg m 3) and glacier-influenced McGinnis Creeks (0.38 mg m 3). However, seasonal patterns ofinvertebrate drift were temporally asynchronous between the two streams. Invertebrate drift and modeledfishgrowth were generally higher in McGinnis Creek in the spring and Montana Creek in the Summer. For juvenilesalmon, tracking these resource asynchronies by moving between tributaries resulted in 20% greater growththan could be obtained within either stream alone. These results suggest that hydrologic heterogeneity withinwatersheds may enhance the diversity of foraging and growth opportunities for mobile aquatic organisms,which may be essential for supporting productive and resilient natural salmon runs.Ye