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 Ursinus Weekly, April 17, 1950

Junior prom to highlight week\u27s social calendar • Forum to present prominent explorer for monthly event • Students select leaders for WSGA, WAA, and Y • Senator to address PAC Wednesday • IRC group attends model UN assembly • French club plans April piano recital • ICG members help draft constitution • Scientists to participate in Y-sponsored panel • Practices continue for spring comedy • Board names six to Weekly editorial staff • Commission to discuss admittance of Negroes • \u27Waltz dream\u27 scores hit with Ursinus audiences • P.A.C. visits Washington on annually planned trip • Swedish books add variety to library language shelves • Alumnus suggests constitution change for alumni group • Three men and a rebel tour southland as vacation interrupts semester work • Ursinus welcomes new dance band • Grizzly nine tours south; trip is judged successful • Rampaging grizzlies open season with pair of wins • Tennis belles open against Bryn Mawr • Nine veterans back for softball season • Stine and Shreiner win men\u27s, girls\u27 intramurals • Gurzynski is named head football coach for 1950 • Annex wins honors on intramural night • Garris\u27 pageant selected for \u2750 May Day themehttps://digitalcommons.ursinus.edu/weekly/1589/thumbnail.jp

The Ursinus Weekly, January 14, 1952

MSGA to enforce campus parking; new fines listed • Navy to send officer here for interviews • FTA hears lecture on visual aid subject • Dr. Phillips attends meeting of foreign student advisors • Forum speaker evaluates Middle East in address • May Queen petitions to go out Feb. 4; Pageant deadline set for February 27 • Rosicrucians add members; Tea is planned • Professors\u27 panel needs questions • Music Club picks Spring operetta • Interest lack hits debating society • Dolman to read • Music Club gives annual recital featuring students • Delta Pi Sigma pledges to work to improve campus • Re-election for Ruby business manager planned by Juniors • Editorials: Is it fair?; We still like heroes • Letters to the editor • English college rules differ from Ursinus\u27 • Engagement announced • Birth announced • Chess provides ground for exercise of mind\u27s caution, logic, memory • Projects planned for improvement of Y rec center • Boobies run acoustics in Bomberger • Bruins topple Haverford 76-59 for first league court victory • Wrestlers defeated by Lafayette team • Marguerite Spencer is chosen captain of 1952 girls\u27 basketball squad • Dorm squads battle for campus court crown • Mack assigned • Bruins register four pins to down Garnet matmen • New record set • Delaware beats Ursinus, 81-52 • Sorority members hold partieshttps://digitalcommons.ursinus.edu/weekly/1532/thumbnail.jp

The Ursinus Weekly, February 11, 1952

Lorelei set for Feb. 29th; Leigh\u27s Orchestra to play • 70 students on coveted B-list; 58 ineligible • Soph class to aid former member • Art instructions now offered by teacher • Curtain Club groups to stage two shows • Second marriage seminar planned Wednesday • May Day petitions due today • Pianist, violinist to play here in Bomberger concert • Weekly staff changes made • Lantern deadline set • Anne Hughes to speak at freshmen Color Day • 26 enroll as new students this semester • Barn dance set by Y Friday night • Dr. Yost makes TV debut in literature program • Tom Phillips elected new Ruby co-business manager • Communist poser to speak on experiences at Forum • Editorials: This was no flop; Elizabeth must provide symbol of solidarity for English people • Dr. Paisley named Layman of the Year • English university has 88 clubs; Atmosphere is international • Engagements • Chess Club JVs lose • Pfahler honored • Saporoschenko takes teaching assistantship at Washington University • Former Ursinus student is now busy recruiting for WAC in Norristown • Leap Year tactics are disclosed; Sirens have a heyday - males beware • Curtis and 724 lead league • Jayvees trounced by Lehigh Quintet, 78-43 • Robert Swett is honored by Philadelphia scribes • Haverford matmen beat Ursinus, 18-16 • Swarthmore defeats Junior varsity squad • Engineers win over Grizzlies • Garnet basketball team downed by Bruins, 69-61 • Snell\u27s Belles win basketball opener • Junior varsity girls basketball squad beats Swarthmore team • Pre-medders hear arthritis lecture • WSGA discusses plans for future events on calendar • Military chemistry subject of talk to students • WAA card party tonighthttps://digitalcommons.ursinus.edu/weekly/1533/thumbnail.jp

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

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

The Ursinus Weekly, December 3, 1951

26 men join frats after rush week • Library used book sale begins today • Chem group lists water program • Light up the sky scores hit as first stage offering • Messiah features highly-rated soloists • Christmas plans made by WSGA; Lights needed • Private lives given as group production by new club members • English Club takes in new members • French Club plans party • Senior ball theme set for Friday • Y panel discusses army conscription • FTA to hear talk on teaching ways • Editorials: A pledge is a pledge; World discusses peace • Bob Herber describes room at University of Bristol, England • Senior prom themes remain centered about winter in past several years • Posters now made by freshmen girls for all activities • Supply Store improvements came with Navy moving to Ursinus campus during war years • Frank Merriwell saves the day • Jayvees defeat Penn; Have undefeated year • Graduating seniors vacate five positions on Ursinus soccer team • Swimming team loses one from last year\u27s squad • Eleven senior men bid farewell to college football playing careers • Albright defeats Curtis Hall team • Penn ties Belles in final contest • Miss Snell loses six hockey girls • Boyd to captain hockey squad in the 1952 season • Youth rally planned • Day students slate party • McClures to entertain • Concert listed • Students must return Ruby proofs by Fridayhttps://digitalcommons.ursinus.edu/weekly/1529/thumbnail.jp

The Ursinus Weekly, December 3, 1951

26 men join frats after rush week • Library used book sale begins today • Chem group lists water program • Light up the sky scores hit as first stage offering • Messiah features highly-rated soloists • Christmas plans made by WSGA; Lights needed • Private lives given as group production by new club members • English Club takes in new members • French Club plans party • Senior ball theme set for Friday • Y panel discusses army conscription • FTA to hear talk on teaching ways • Editorials: A pledge is a pledge; World discusses peace • Bob Herber describes room at University of Bristol, England • Senior prom themes remain centered about winter in past several years • Posters now made by freshmen girls for all activities • Supply Store improvements came with Navy moving to Ursinus campus during war years • Frank Merriwell saves the day • Jayvees defeat Penn; Have undefeated year • Graduating seniors vacate five positions on Ursinus soccer team • Swimming team loses one from last year\u27s squad • Eleven senior men bid farewell to college football playing careers • Albright defeats Curtis Hall team • Penn ties Belles in final contest • Miss Snell loses six hockey girls • Boyd to captain hockey squad in the 1952 season • Youth rally planned • Day students slate party • McClures to entertain • Concert listed • Students must return Ruby proofs by Fridayhttps://digitalcommons.ursinus.edu/weekly/1529/thumbnail.jp

From canopy to consumer: what makes and modifes terrestrial DOM in a temperate forest

To investigate how source and processing control the composition of “terrestrial” dissolved organic matter (DOM), we combine soil and tree leachates, tree DOM, laboratory bioincubations, and ultrahigh resolution Fourier-transform ion cyclotron resonance mass spectrometry in three common landscape types (upland forest, forested wetland, and poor fen) of Southeast Alaska’s temperate rainforest. Tree (Tsuga heterophylla and Picea sitchensis) needles and bark and soil layers from each site were leached, and tree stemflow and throughfall collected to examine DOM sources. Dissolved organic carbon concentrations were as high as 167 mg CL−1 for tree DOM, suggesting tree DOM fluxes may be substantial given the hypermaritime climate of the region. Condensed aromatics contributed as much as 38% relative abundance of spruce and hemlock bark leachates suggesting coniferous trees are potential sources of condensed aromatics to surface waters. Soil leachates showed soil wetness dictates DOM composition and processing, with wetland soils producing more aromatic formulae and allowing the preservation of traditionally biolabile, aliphatic formulae. Biodegradation impacted soil and tree DOM differently, and though the majority of source-specific marker formulae were consumed for all sources, some marker formulae persisted. Tree DOM was highly biolabile (> 50%) and showed compositional convergence where processing homogenized DOM from different tree sources. In contrast, wetland and upland soil leachate DOM composition diverged and processing diversified DOM from different soil sources during bioincubations. Increasing precipitation intensity predicted with climate change in Southeast Alaska will increase tree leaching and soil DOM flushing, tightening linkages between terrestrial sources and DOM export to the coastal ocean.The authors thank Emily Whitney for her invaluable feld, laboratory, and logistical assistance and Molly Tankersley for creating Fig. 1. They are also grateful to all the helpful researchers at the National High Magnetic Field Laboratory who enabled data acquisition and processing. This work took place on the lands of the Aak’w Kwáan Tlingit. This work was supported by the National Science Foundation through an NSF Graduate Research Fellowship to MIB. A portion of this work was performed at the National High Magnetic Field Laboratory ICR User Facility, which is supported by the National Science Foundation Division of Chemistry and Division of Materials Research through DMR-1644779 and the State of Florida. Conficts of interest/ Competing interests: The authors have no conficts of interests to declare.Ye