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Full-Text Articles in Physical Sciences and Mathematics

Vitamin E Circular Dichroism Studies: Insights Into Conformational Changes Induced By The Solvent’S Polarity, Drew Marquardt, Brad J. Van Oosten, Mikel Ghelfi, Jeffrey Atkinson, Thad A. Harroun Dec 2016

Vitamin E Circular Dichroism Studies: Insights Into Conformational Changes Induced By The Solvent’S Polarity, Drew Marquardt, Brad J. Van Oosten, Mikel Ghelfi, Jeffrey Atkinson, Thad A. Harroun

Chemistry and Biochemistry Publications

We used circular dichroism (CD) to study differences in CD spectra between α-, δ-, and methylated-α-tocopherol in solvents with different polarities. CD spectra of the different tocopherol structures differ from each other in intensity and peak locations, which can be attributed to chromanol substitution and the ability to form hydrogen bonds. In addition, each structure was examined in different polarity solvents using the Reichardt index—a measure of the solvent’s ionizing ability, and a direct measurement of solvent–solute interactions. Differences across solvents indicate that hydrogen bonding is a key contributor to CD spectra at 200 nm. These results are a first …


Morphology-Induced Defects Enhance Lipid Transfer Rates, Yan Xia, Kamil Charubin, Drew Marquardt, Frederick A. Heberle, John Katsaras, Jianhui Tian, Xiaolin Cheng, Ying Liu, Mu Ping Nieh Sep 2016

Morphology-Induced Defects Enhance Lipid Transfer Rates, Yan Xia, Kamil Charubin, Drew Marquardt, Frederick A. Heberle, John Katsaras, Jianhui Tian, Xiaolin Cheng, Ying Liu, Mu Ping Nieh

Chemistry and Biochemistry Publications

Molecular transfer between nanoparticles has been considered to have important implications regarding nanoparticle stability. Recently, the interparticle spontaneous lipid transfer rate constant for discoidal bicelles was found to be very different from spherical, unilamellar vesicles (ULVs). Here, we investigate the mechanism responsible for this discrepancy. Analysis of the data indicates that lipid transfer is entropically favorable, but enthalpically unfavorable with an activation energy that is independent of bicelle size and long- to short-chain lipid molar ratio. Moreover, molecular dynamics simulations reveal a lower lipid dissociation energy cost in the vicinity of interfaces ("defects") induced by the segregation of the long- …


Cholesterol's Location In Lipid Bilayers, Drew Marquardt, Norbert Kučerka, Stephen R. Wassall, Thad A. Harroun, John Katsaras Sep 2016

Cholesterol's Location In Lipid Bilayers, Drew Marquardt, Norbert Kučerka, Stephen R. Wassall, Thad A. Harroun, John Katsaras

Chemistry and Biochemistry Publications

It is well known that cholesterol modifies the physical properties of lipid bilayers. For example, the much studied liquid-ordered Lo phase contains rapidly diffusing lipids with their acyl chains in the all trans configuration, similar to gel phase bilayers. Moreover, the Lo phase is commonly associated with cholesterol-enriched lipid rafts, which are thought to serve as platforms for signaling proteins in the plasma membrane. Cholesterol's location in lipid bilayers has been studied extensively, and it has been shown – at least in some bilayers – to align differently from its canonical upright orientation, where its hydroxyl group is in the …


Insights From Molecular Dynamics On Substrate Binding And Effects Of Active Site Mutations In Delta1-Pyrroline-5-Carboxylate Dehydrogenase, Bogdan F. Ion, Mohamed M. Aboelnga, James W. Gauld Aug 2016

Insights From Molecular Dynamics On Substrate Binding And Effects Of Active Site Mutations In Delta1-Pyrroline-5-Carboxylate Dehydrogenase, Bogdan F. Ion, Mohamed M. Aboelnga, James W. Gauld

Chemistry and Biochemistry Publications

The NAD+-dependent enzyme, 1-pyrroline-5-carboxylate dehydrogenase (P5CDH), has an important role in proline and hydroxyproline catabolism for humans. Specifically, this aldehyde dehydrogenase is responsible for the oxidation of both L-glutamate- -semialdehyde (GSA) and 4-erythro-hydroxy-L-glutamate- -semialdehyde (4-OH-GSA) to their respective L-glutamate product forms. We have performed a detailed molecular dynamics (MD) study of both the reactant and product complex structures of P5CDH to gain insights into ligand binding (i.e., GSA, 4-OH-GSA, NAD+, GLU) in the active site. Moreover, our investigations were further extended to examine the structural impact of S352L, S352A, and E314A mutations on the deficiency in the P5CDH enzymatic activity. …


Elastomers: Reinventing Butyl Rubber For Stretchable Electronics (Adv. Funct. Mater. 29/2016), Akhil Vohra, Heather L. Filiatrault, Stanley D. Amyotte, R. Stephen Carmichael, Natalie D. Suhan, Conrad Siegers, Lorenzo Ferrari, Gregory J.E. Davidson, Tricia Breen Carmichael Aug 2016

Elastomers: Reinventing Butyl Rubber For Stretchable Electronics (Adv. Funct. Mater. 29/2016), Akhil Vohra, Heather L. Filiatrault, Stanley D. Amyotte, R. Stephen Carmichael, Natalie D. Suhan, Conrad Siegers, Lorenzo Ferrari, Gregory J.E. Davidson, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

No abstract provided.


Polyisobutylene-Paclitaxel Conjugates With Pendant Carboxylic Acids And Polystyrene Chains: Towards Multifunctional Stent Coatings With Slow Drug Release, John F. Trant, Mahmoud M. Abd Rabo Moustafa, Inderpreet Sran, Elizabeth R. Gillies Jul 2016

Polyisobutylene-Paclitaxel Conjugates With Pendant Carboxylic Acids And Polystyrene Chains: Towards Multifunctional Stent Coatings With Slow Drug Release, John F. Trant, Mahmoud M. Abd Rabo Moustafa, Inderpreet Sran, Elizabeth R. Gillies

Chemistry and Biochemistry Publications

Drug-eluting stents are used in the treatment of atherosclerosis, where the incorporation of anti-proliferative or anti-inflammatory drugs decreases the rate of restenosis, the recurrence of artery narrowing. However, these stents can suffer from limitations such as drug depletion and delamination of the drug-eluting coating from the stent surface. Described here is an approach aimed at addressing these issues. Starting from a maleic anhydride adduct of polyisobutylene (PIB) prepared from butyl rubber, ring opening using paclitaxel (PTX) or a combination of PTX and polystyrene (PS) afforded covalent conjugates of PTX and PIB or PIB-PS graft copolymers bearing pendant carboxylic acids. When …


Great Lakes Focus On Water Quality: Vol.4 Iss.3, Uwindsor Administrator Jun 2016

Great Lakes Focus On Water Quality: Vol.4 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

In October and November the Pollution from Land Use Activities Reference Group (PLUARG) will sponsor information meetings throughout the Great Lakes Basin. The purposes of the sessions are to present the PLUARG final report, Environmental Management Strategy for the Great Lakes System, with its conclusions and recomendations (See PLUARG write up, page 6), explain the IJC's hearing process, and encourage people to present their views on the report to the Commission on Public Hearings.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

Enlightened public opinion ultimately set things right in the Reserve Mining case. Following US. District Judge Miles Lord’s order of April 20, 1974 to cease all taconite tailings discharge to Lake Superior, it took much additional effort by the State of Minnesota, intervening environmental groups and the US. Government to stop the 25-year dumping of hundreds of millions of tons of tailings into the world’s fresh- water treasure. It finally happened in the spring of 1980


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

The glacial history of the Great Lakes basin and the tremendous influence of the lakes themselves create unique conditions. These support a wealth of biological diversity, including many species and communities of global significance. The basin’s sand dunes, coastal marsh- es, rocky shorelines, lakeplain prairies, savannas, forests, fens and other landscapes contain features that are either unique to or are best represented with- in the Great Lakes basin. The remark- able biodiversity of the Great Lakes basin is illustrated by the Indiana Dunes National Lakeshore. This park ranks third among US. National Parks in plant diversity, yet its area is …


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.19 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

In its Seventh Biennial Report on Great Lakes Water Quality (signed in 1993), released this February, the International Joint Commission again concludes that contamination by various persistent toxic substances is ' the biggest problem facing the Great Lakes ecosystem. The Governments of the United States and Canada are committed to restoring and protecting the Great Lakes and the Commission’s reports assist them by identifying progress and further needs.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

Drawn by a highly Visible recommendation to sunset industrial uses of chlorine, a record-setting 1,900 participants came to the International Joint Commission’s Biennial Meeting on Great Lakes Water Quality in Windsor, Ontario. Participants at the October 21-24, 1993 event also represented a broader spectrum of society than at previous biennial meetings.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

Indianapolis started it all in 1983, when 300 people joined the International Joint Commission for its first Biennial Meeting on Great Lakes Water Quality. Kingston was next in 1985, followed by Toledo in 1987, Hamilton in 1989, and Traverse City in 1991, when more than 1,600 people participated in the meeting. Now, ten years later, Windsor will host the International Joint Commission’s 1993 Biennial Meeting on Great Lakes Water Quality. Why does the Commission hold these meetings, what issues are addressed, and how can attendees participate in this year’s sessions ?


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.18 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

The Virtual Elimination Task Force, appointed by the International Joint Commission in the summer of 1990 to recommend a strategy for virtually eliminating the input of persistent toxic substances to the Great Lakes environment, has released its draft final report for public comment.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

When the headaches won't disappear or our child has a languishing cough, we Visit our physician to obtain a cure for our ills. As a society, studies Show that North Americans have a high level of trust in the ability of our doctors to identify possible causes and to prescribe the best solution to our ailments. How likely are our doctors to consider pollutants in our environment as a possible cause of our problems ?


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

In mid-June, Commissioner Hilary Cleveland and Commission staff visited four communities on the north shore of Lake Superior to meet with the local Remedial Action Plan (RAP) teams, Public Advisory Committee (PAC) members, RAP technical re- viewers, local news media and others interested in the cleanup plans in the four North Shore Areas of Concern: Jackfish Bay, Nipigon Bay, Peninsula Harbour and Thunder Bay.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.17 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

Thus concludes the International Joint Commission in its Sixth Biennial Report on Great lakes Water Quality, released in mid- April on the 20th anniversary of the signing of the Great Lakes Water Quality Agreement. The Commission’s report focuses on persistent toxic sub- stances, and the steps needed to reach the Great Lakes Water Quality Agreement’s goal of virtual elimination of the inputs of these substances to the Great Lakes system.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

Representatives from diverse interests came to discuss their concerns with the International Joint Commission and each other at the 1991 Biennial Meeting on Great Lakes Water Quality in Traverse City, Michigan, September 29 through October 2, 1991. Biennial Meetings are held by the Commission before it prepares recommendations to the Governments of the United States and Canada and the Great Lakes state and provincial governments in accordance with the Great Lakes Water Quality Agreement.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

The Grand Traverse Bay is the focal point of the northwest region of Michigan's lower peninsula, and area residents are vividly aware of its beauty and delicacy. Traverse City, a town of about 20,000 people, historically has pooled its human resources to protect its natural ones. As the International Joint Commission’s (IJC) 1991 Biennial Meeting approaches (see page 11 for registration and program information), local energies have intensified to focus on Grand Traverse Bay protection efforts, and conference participants will be impressed by the splendor of the Grand Traverse Bay and the dedication of local people to protect the bay’s …


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.16 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

The intent of these listing / delisting guidelines is to serve as indicators of use impairment for Great Lakes Areas of Concern and will be used to assist the International Joint Commission (IIC) and its Boards in: 1) making recommendations for new Areas of Concern; and 2) reviewing all stages of remedial action plans (RAPs). These guidelines are intended to establish a consistent “set of yard- sticks” that can be uniformly applied throughout the Great Lakes basin. Further, these guidelines are in— tended to help ensure that the RAP program is properly focused and pragmatic so that it clearly identifies …


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.11 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.11 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

As a result of the continuing high water levels on the Great Lakes,the Governments of Canada and the United States have asked the IJC to examine and report on ways to alleviate the adverse consequences of fluctuating water levels, in terms of both the immediate high level crisis and the long term consequences. Record high levels are continuing throughout most of the Great Lakes basin, except on Lake Ontario. While levels are expected to stay below recorded maximums on Lake Ontario and Lake Superior, levels on these lakes will remain high if extreme water supplies continue.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.11 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.11 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

No abstract provided.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

In a recently released joint report to the Governments of the United States and Canada, the International Joint Commission (IIC) and the Great Lakes Fishery Com— mission (GLFC) warned that additional "massive and calamitous invasions” of exotic species could occur if preventive actions are not taken immediately to stop the introduction of such species into the Great Lakes Basin Ecosystem.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

Under the 1987 Protocol revising the 1978 Great Lakes Water Quality Agreement, the International Joint Commission (IJC) is responsible for reviewing and commenting on the adequacy of Re- medial Action Plans (RAPs) for Areas of Concern in the Great Lakes - St. Lawrence River basin. In its recently released Fifth Biennial Report on Great Lakes Water Quality, the IJC concluded that RAPS provide "a unique experiment in institutional cooperation and the first opportunity, on a broad and practical scale, to implement the ecosystem approach to environmental restoration in the Great Lakes basin."


Focus On Great Lakes Water Quality (Issn 0711-0855): Vol.11 Iss.1, Uwindsor Administrator Apr 2016

Focus On Great Lakes Water Quality (Issn 0711-0855): Vol.11 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

Anyone who lives in the Great Lakes region knows the lure of water - the beauty of the lakes calls residents to move to their shore- lines and enjoy the sounds, smells and scenery the water provides. These residents also know the concern and frustration when the lakes extend beyond the boundaries to which it was thought the water would abide. The results of higher than expected lake levels are flooded basements, ravaged bluffs and anxious homeowners who are desperate for answers as to when the waters will recede.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.15 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

The International Joint Com- mission (IIC) has issued its Fifth Biennial Report on Great Lakes Water Quality. In it, the Com- mission places major emphasis on persistent toxic substances, their potential impacts on human health and the urgent need for a comprehensive and effective strategy to deal with them.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

Zero discharge of persistent toxic substances; involvement by municipal governments to protect water quality; incorporating land use planning elements into remedial action plans; the invasion of zebra mussels; and shifting from reactive to proactive attitudes in all programs developed to restore and protect the Great Lakes Basin Ecosystem. These and many other issues were presented by conference participants to the International Joint Commission (IJC) during the 1989 Biennial Meeting on Great Lakes Water Quality.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

Hamilton Harbour, a deep water port which supports the largest iron and steel industrial complex in Canada, receives runoff and waste effluent from its western rural area as well as the eastern urbanized region. A remedial action plan (RAP) team with representatives from Ontario’s Ministries of the Environment, Natural Resources, and Agriculture and Food, Environment Canada, Royal Botanical Gardens and the Department of Fisheries and Oceans was formed in May 1986 to identify sources of pollution and steps and timetables in the remediation process, and to work closely with the community-wide stakeholder groups in developing and implementing the remedial action …


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.1, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.14 Iss.1, Uwindsor Administrator

Focus on International Joint Commission Activities

The 1978 Great Lakes Water Quality Agreement requires the International Joint Commission (IJC) to make a full report at least every two years to the Governments of the United States and Canada and to state and provincial governments concerning progress to accomplish the goals of the Agreement.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.13 Iss.3, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.13 Iss.3, Uwindsor Administrator

Focus on International Joint Commission Activities

As this issue of Focus went to press, the International Joint Commission had received a request from the Governments of Canada and the United States to recommence its activities with respect to monitoring and reporting on air pollution emissions and their impacts in the Detroit— Windsor and Port Huron- Sarnia region of the international boundary.


Focus On International Joint Commission Activities (Issn 0832-6673): Vol.13 Iss.2, Uwindsor Administrator Apr 2016

Focus On International Joint Commission Activities (Issn 0832-6673): Vol.13 Iss.2, Uwindsor Administrator

Focus on International Joint Commission Activities

If patience is indeed a virtue, then E the group that assembled on the shores of Lake Erie on the morning of March 26, 1988 possessed a lot of it. Many of those who gathered that day in Cleveland had worked for more than a decade to reach that moment: the signing of the long-awaited, much debated and urgently needed law to ban high phosphate detergents in Ohio.