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2. Thematic Analysis of Psychosocial Stressors and Adaptive Coping Strategies Among Informal Caregivers of Patients Surviving ICU Admission for Coma

Author

Hwang, David Y., Bannon, Sarah M., Meurer, Kate, Kubota, Rina, Baskaran, Nithyashri, Kim, Jisoo, Zhang, Qiang, Reichman, Mira, Fishbein, Nathan S., Lichstein, Kaitlyn, Motta, Melissa, Muehlschlegel, Susanne, Reznik, Michael E., Jaffa, Matthew N., Creutzfeldt, Claire J., Fehnel, Corey R., Tomlinson, Amanda D., Williamson, Craig A., and Vranceanu, Ana-Maria

Published
2024
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10. Consequences of changing water clarity on the fish and fisheries of the Laurentian Great Lakes

Author

Bunnell, David B., Ludsin, Stuart A., Knight, Roger L., Rudstam, Lars G., Williamson, Craig E., Hook, Tomas O., Collingsworth, Paris D., Lesht, Barry M., Barbiero, Richard P., Scofield, Anne E., Rutherford, Edward S., Gaynor, Layne, Vanderploeg, Henry A., and Koops, Marten A.

Subjects
Great Lakes (North America) -- Environmental aspects, Fishes -- Environmental aspects, Fisheries -- Environmental aspects, Fish industry -- Environmental aspects, Water turbidity -- Environmental aspects, Earth sciences
Abstract

Human-driven environmental change underlies recent changes in water clarity in many of the world's great lakes, yet our understanding of the consequences of these changes on the fish and fisheries they support remains incomplete. Herein, we offer a framework to organize current knowledge, guide future research, and help fisheries managers understand how water clarity can affect their valued populations. Emphasizing Laurentian Great Lakes findings where possible, we describe how changing water clarity can directly affect fish populations and communities by altering exposure to ultraviolet radiation, foraging success, predation risk, reproductive behavior, or territoriality. We also discuss how changing water clarity can affect fisheries harvest and assessment through effects on fisher behavior and sampling efficiency (i.e., catchability). Finally, we discuss whether changing water clarity can affect understudied aspects of fishery performance, including economic and community benefits. We conclude by identifying generalized predictions and discuss their implications for priority research questions for the Laurentian Great Lakes. Even though the motivation for this work was regional, the breadth of the review and generality of the framework are readily transferable to other freshwater and marine habitats. Si des modifications de l'environnement causees par les humains sous-tendent les changements recents de la clarte de l'eau dans bon nombre des grands lacs de la planete, notre comprehension des consequences de ces changements sur les poissons et les peches qu'ils soutiennent demeure incomplete. Nous presentons un cadre pour organiser les connaissances actuelles, orienter la recherche future et aider les gestionnaires des peches a comprendre l'incidence possible de la clarte de l'eau sur les populations qu'ils gerent. En mettant l'accent, dans la mesure du possible, sur des constatations relatives aux Grands Lacs laurentiens, nous decrivons l'incidence directe que peuvent avoir les variations de la clarte de l'eau sur les populations et communautes de poissons en modifiant l'exposition au rayonnement ultraviolet, le succes d'approvisionnement, le risque de predation, le comportement de reproduction ou la territorialite. Nous abordons egalement l'incidence que peuvent avoir les modifications de la clarte de l'eau sur les prises et revaluation des peches par le biais d'effets sur le comportement des pecheurs et l'efficacite d'echantillonnage (c.-a-d., la capturabilite). Enfin, nous tentons d'etablir si les modifications de la clarte de l'eau peuvent avoir une incidence sur des aspects sous-etudies de la performance des peches, y compris les avantages economiques et pour les collectivites. Nous concluons en formulant des predictions generales et discutons des questions de recherche prioritaires qu'elles font ressortir pour les Grands Lacs laurentiens. Meme si l'intention a l'origine du present article etait regionale, la portee de la synthese et le caractere general du cadre font qu'ils peuvent etre transposes aisement a d'autres habitats marins et d'eau douce. [Traduit par la Redaction], Introduction Although scientists have increasingly documented changing water clarity in freshwater ecosystems worldwide, we do not fully understand its effects on aquatic food webs and the fisheries that they support. [...]

Published
2021
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13. Widespread deoxygenation of temperate lakes

Author

Jane, Stephen F., Hansen, Gretchen J. A., Kraemer, Benjamin M., Leavitt, Peter R., Mincer, Joshua L., North, Rebecca L., Pilla, Rachel M., Stetler, Jonathan T., Williamson, Craig E., Woolway, R. Iestyn, Arvola, Lauri, Chandra, Sudeep, DeGasperi, Curtis L., Diemer, Laura, Dunalska, Julita, Erina, Oxana, Flaim, Giovanna, Grossart, Hans-Peter, Hambright, K. David, Hein, Catherine, Hejzlar, Josef, Janus, Lorraine L., Jenny, Jean-Philippe, Jones, John R., Knoll, Lesley B., Leoni, Barbara, Mackay, Eleanor, Matsuzaki, Shin-Ichiro S., McBride, Chris, Müller-Navarra, Dörthe C., Paterson, Andrew M., Pierson, Don, Rogora, Michela, Rusak, James A., Sadro, Steven, Saulnier-Talbot, Emilie, Schmid, Martin, Sommaruga, Ruben, Thiery, Wim, Verburg, Piet, Weathers, Kathleen C., Weyhenmeyer, Gesa A., Yokota, Kiyoko, and Rose, Kevin C.

Published
2021
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16. Global data set of long-term summertime vertical temperature profiles in 153 lakes

Author

Pilla, Rachel M., Mette, Elizabeth M., Williamson, Craig E., Adamovich, Boris V., Adrian, Rita, Anneville, Orlane, Balseiro, Esteban, Ban, Syuhei, Chandra, Sudeep, Colom-Montero, William, Devlin, Shawn P., Dix, Margaret A., Dokulil, Martin T., Feldsine, Natalie A., Feuchtmayr, Heidrun, Fogarty, Natalie K., Gaiser, Evelyn E., Girdner, Scott F., González, María J., Hambright, K. David, Hamilton, David P., Havens, Karl, Hessen, Dag O., Hetzenauer, Harald, Higgins, Scott N., Huttula, Timo H., Huuskonen, Hannu, Isles, Peter D. F., Joehnk, Klaus D., Keller, Wendel Bill, Klug, Jen, Knoll, Lesley B., Korhonen, Johanna, Korovchinsky, Nikolai M., Köster, Oliver, Kraemer, Benjamin M., Leavitt, Peter R., Leoni, Barbara, Lepori, Fabio, Lepskaya, Ekaterina V., Lottig, Noah R., Luger, Martin S., Maberly, Stephen C., MacIntyre, Sally, McBride, Chris, McIntyre, Peter, Melles, Stephanie J., Modenutti, Beatriz, Müller-Navarra, Dörthe C., Pacholski, Laura, Paterson, Andrew M., Pierson, Don C., Pislegina, Helen V., Plisnier, Pierre-Denis, Richardson, David C., Rimmer, Alon, Rogora, Michela, Rogozin, Denis Y., Rusak, James A., Rusanovskaya, Olga O., Sadro, Steve, Salmaso, Nico, Saros, Jasmine E., Sarvala, Jouko, Saulnier-Talbot, Émilie, Schindler, Daniel E., Shimaraeva, Svetlana V., Silow, Eugene A., Sitoki, Lewis M., Sommaruga, Ruben, Straile, Dietmar, Strock, Kristin E., Swain, Hilary, Tallant, Jason M., Thiery, Wim, Timofeyev, Maxim A., Tolomeev, Alexander P., Tominaga, Koji, Vanni, Michael J., Verburg, Piet, Vinebrooke, Rolf D., Wanzenböck, Josef, Weathers, Kathleen, Weyhenmeyer, Gesa A., Zadereev, Egor S., and Zhukova, Tatyana V.

Published
2021
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17. Smoke from regional wildfires alters lake ecology

Author

Scordo, Facundo, Chandra, Sudeep, Suenaga, Erin, Kelson, Suzanne J., Culpepper, Joshua, Scaff, Lucia, Tromboni, Flavia, Caldwell, Timothy J., Seitz, Carina, Fiorenza, Juan E., Williamson, Craig E., Sadro, Steven, Rose, Kevin C., and Poulson, Simon R.

Published
2021
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21. Ozone depletion, ultraviolet radiation, climate change and prospects for a sustainable future

Author

Barnes, Paul W., Williamson, Craig E., Lucas, Robyn M., Robinson, Sharon A., Madronich, Sasha, Paul, Nigel D., Bornman, Janet F., Bais, Alkiviadis F., Sulzberger, Barbara, Wilson, Stephen R., Andrady, Anthony L., McKenzie, Richard L., Neale, Patrick J., Austin, Amy T., Bernhard, Germar H., Solomon, Keith R., Neale, Rachel E., Young, Paul J., Norval, Mary, Rhodes, Lesley E., Hylander, Samuel, Rose, Kevin C., Longstreth, Janice, Aucamp, Pieter J., Ballaré, Carlos L., Cory, Rose M., Flint, Stephan D., de Gruijl, Frank R., Häder, Donat-P., Heikkilä, Anu M., Jansen, Marcel A. K., Pandey, Krishna K., Robson, T. Matthew, Sinclair, Craig A., Wängberg, Sten-Åke, Worrest, Robert C., Yazar, Seyhan, Young, Antony R., and Zepp, Richard G.

Published
2019
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23. Deeper waters are changing less consistently than surface waters in a global analysis of 102 lakes

Author

Pilla, Rachel M., Williamson, Craig E., Adamovich, Boris V., Adrian, Rita, Anneville, Orlane, Chandra, Sudeep, Colom-Montero, William, Devlin, Shawn P., Dix, Margaret A., Dokulil, Martin T., Gaiser, Evelyn E., Girdner, Scott F., Hambright, K. David, Hamilton, David P., Havens, Karl, Hessen, Dag O., Higgins, Scott N., Huttula, Timo H., Huuskonen, Hannu, Isles, Peter D. F., Joehnk, Klaus D., Jones, Ian D., Keller, Wendel Bill, Knoll, Lesley B., Korhonen, Johanna, Kraemer, Benjamin M., Leavitt, Peter R., Lepori, Fabio, Luger, Martin S., Maberly, Stephen C., Melack, John M., Melles, Stephanie J., Müller-Navarra, Dörthe C., Pierson, Don C., Pislegina, Helen V., Plisnier, Pierre-Denis, Richardson, David C., Rimmer, Alon, Rogora, Michela, Rusak, James A., Sadro, Steven, Salmaso, Nico, Saros, Jasmine E., Saulnier-Talbot, Émilie, Schindler, Daniel E., Schmid, Martin, Shimaraeva, Svetlana V., Silow, Eugene A., Sitoki, Lewis M., Sommaruga, Ruben, Straile, Dietmar, Strock, Kristin E., Thiery, Wim, Timofeyev, Maxim A., Verburg, Piet, Vinebrooke, Rolf D., Weyhenmeyer, Gesa A., and Zadereev, Egor

Published
2020
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27. Imidazolylidenes in N-heterocyclic carbene organo-catalysis

Author

Williamson, Craig

Subjects
547.215
Abstract

A library of chiral and achiral imidazolium salts was prepared, and evaluated as potential pre-catalysts of the benzoin condensation.  It was found that although the carbenes derived from these compounds possess catalytic activity, this was not as pronounced as that observed for alternative heterocycle classes.  Asymmetric induction, although observed from imidazolylidenes for the first time in this work, is not of an order that could be considered useful, as has been seen for other NHC catalysts.  This is attributed to the use of harsh reaction conditions, required to promote catalytic activity in this system. Two modifications were thus made to the imidazolium salt pre-catalysts in an attempt to make the reaction conditions less extreme.  Imidazolium carboxylates were found to be suitable pre-catalysts, thus allowing the reaction to be performed under neutral conditions.  Purinium salts were also investigated, based on the theory that these more electron deficient fused heterocycles would allow access to carbenes under milder conditions.  Although problems were encountered in the synthesis of these salts, one example was prepared, however the available data indicate this exists as the incorrect regioisomer. Two strategies for catalyst immobilisation have also been investigated.  It was found that polymer supported imidazolylidenes are capable of catalysing the benzoin condensation of a range of aromatic aldehydes, under a range of conditions, and can undergo a limited number of recycles.  Imidazolium salts supported on silica were found to be unsuitable for the catalysis of this reaction.  This was blamed on incompatibility of the persistently acidic matrix with the basic conditions required by the carbene. Application of imidazolylidenes to the intra-molecular Stetter reaction was also attempted, however this revealed NHC have the ability to act catalytically as bases.  Further investigation of this observation suggested the effect is limited to α,β-unsaturated carbonyl compounds.

Published
2006

29. External quality assessment in the context of managerialism and higher education public policy

Author

Williamson, Craig James

Subjects
378.10709411
Abstract

A core aspect of higher education public policy developments in Scotland has been the external quality assessment of learning and teaching provision. Controversial in their own right, such processes were often overshadowed by conflicts regarding the policy of accountability to Government and the apparent attack on university and staff autonomy. Thus, the research is set within a context of conflicting internal and external environments. Rapidly and radically changing public policy and perspectives of state-sector and institution-department managerialism gave conflicts over external accountability policy and external quality assessment processes broader significance. The research adopted a qualitative case study methodology, incorporating thirty six semistructured interviews with key sector, institutional and departmental informants. The carefully selected informants had extensive experience of external quality assessment in Scottish universities and of sector, institutional and departmental perceptions and responses. Conclusions establish that external quality assessment has, across the Scottish university sector, had a positive catalytic influence on the enhancement or revitalisation of the institutional and departmental focus on assuring and improving the quality of learning and teaching provision, on a long-term basis. However, significant obstacles to a continued beneficial interface are evident and the need for external approaches to instil ownership of quality assurance and enhancement with subject level academics is underlined. Implications assert that continuing and principled policy conflict regarding the imposition of an externally driven change process of disputed relevance on a (semi) autonomous institution or sector will not necessarily fatally impede the process from having a beneficial catalytic impact, provided that factors internal and external to the institution combine to create an appropriate environment. Further, this can occur across a sector of similar but culturally distinct institutions. However, it is evident that processes may have only a limited impact and must evolve if there is to be a continuing benefit, as the internal and external factors that have combined to create an environment open to influence may change. Given that change processes in public and private sectors can also result in conflict between internal and external environmental factors, the implications may extend beyond the Scottish university sector and quality assessment.

Published
2004
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39. Landscape-scale regulators of water transparency in mountain lakes: implications of projected glacial loss

Author

Olson, Mark H., Fischer, Janet M., Williamson, Craig E., Overholt, Erin P., and Theodore, Nora

Subjects
Rocky Mountains -- Environmental aspects, Glaciers -- Environmental aspects, Lakes -- Environmental aspects, Water quality -- Environmental aspects, Earth sciences
Abstract

We examined factors regulating water transparency in a set of 33 lakes located in the Canadian Rocky Mountains. Eighteen lakes had catchments that included glaciers and 15 did not. In each lake, we quantified midsummer attenuation rates for three ultraviolet wavelengths and photosynthetically active radiation and measured chromophoric dissolved organic matter (CDOM) absorbance, turbidity, and chlorophyll a fluorescence. We also used GIS to quantify characteristics of lake catchments. Across lakes, turbidity and CDOM absorbance were arrayed on orthogonal gradients that intersected in a region of low turbidity and low CDOM absorbance. Nonglacially fed lakes had low turbidity and attenuation rates were regulated by CDOM absorbance, which increased with the percentage of the catchment covered by vegetation. Glacially fed lakes had low CDOM absorbance and attenuation rates increased with turbidity, which increased with the percentage of the catchment covered by permanent ice. Glaciers are retreating rapidly in the Canadian Rockies. As catchments become deglaciated, turbidity will likely decrease and the regulator of lake transparency is likely to switch to CDOM, which will have broad implications for lake ecosystems. Nous avons examine les facteurs qui modulent la transparence de l'eau dans un ensemble de 33 lacs situes dans les Rocheuses canadiennes. Les bassins versants de 18 de ces lacs renfermaient des glaciers et ceux des 15 autres, non. Pour chaque lac, nous avons quantifie les taux d'attenuation au milieu de l'ete pour trois longueurs d'onde dans l'ultraviolet et le rayonnement photosynthetiquement actif, et mesure l'absorbance de la matiere organique dissoute chromophore (MODC), la turbidite et la fluorescence de la chlorophylle a. Nous avons egalement utilise les SIG pour quantifier les caracteristiques des bassins versants des lacs. A l'echelle de tous les lacs, la turbidite et l'absorbance de la MODC etaient reparties sur des gradients orthogonaux qui se croisent dans une region de faible turbidite et de faible absorbance de la MODC. Les lacs non alimentes par des glaciers presentaient une faible turbidite et leurs taux d'attenuation etaient modules par l'absorbance de la MODC, qui augmentait parallelement au pourcentage du bassin couvert par la vegetation. Les lacs alimentes par des glaciers avec une faible absorbance de la MODC et leurs taux d'attenuation augmentaient parallelement a la turbidite, qui augmentait parallelement au pourcentage du bassin couvert par des glaces permanentes. Les glaciers fondent rapidement dans les Rocheuses canadiennes. Au fil de la deglaciation des bassins versants, la turbidite diminuera vraisemblablement et la MODC deviendra vraisemblablement le facteur qui modulera la transparence des lacs, ce qui aura d'importantes consequences pour les ecosystemes lacustres. [Traduit par la Redaction], Introduction Water transparency has important physical, chemical, and biological effects on lake ecosystems. Transparency influences lake thermal structure, vertical distributions of phytoplankton and zooplankton, foraging rates of top predators, and [...]

Published
2018
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48. Depth profiles of Jerlov water types.

Author

Williamson, Craig A. and Hollins, Richard C.

Subjects
*DEPTH profiling, *ATTENUATION coefficients, *SEAWATER, *DATABASES, *ACQUISITION of data
Abstract

Typical depth profiles of Jerlov water types have been derived to characterize the clarity of the world's oceans. Measured values of the downwelling diffuse attenuation coefficient, taken from a world‐wide database, were quantitatively analyzed. Depth profiles were extracted from more than 2500 data collection campaigns, consisting of the closest‐matching Jerlov water types at the uppermost layer (0–10 m) and the corresponding Jerlov water types at deeper depth layers down to 200 m. A table of "typical" depth profiles for the 10 Jerlov water types was generated based on the maximum campaign count at each depth layer. This new ocean classification will find use in applications where modeling of typical ocean waters requires the depth‐dependence of clarity to be accounted for. [ABSTRACT FROM AUTHOR]

Published
2023
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