WMHs were uncommon in a younger healthy population screened for comorbid diseases, but increased 10-fold in subjects over 55 years of age. When present, the WMHs are generally small (rating of 0.5). While large WMHs appear to be associated with cognitive deterioration, the optimum threshold for identification, clinical significance, and prognostic value of smaller white matter changes requires further research.

Heterogeneous catalysts are desired for the conversion of glucose, the most abundant sugar in renewable biomass, but presently their synthesis requires highly toxic chemicals with long synthesis times. We report the conversion of glucose into fructose and 5‐hydroxymethylfurfural on a heterogeneous catalyst that is stable and selective and operates in the most environmentally benign solvent, water. We used a bifunctional solid with Lewis and Brønsted acid sites by partially replacing the organic linker of the zirconium organic framework UiO‐66 with 2‐monosulfo‐benzene‐1,4‐dicarboxylate. This catalyst showed high product selectivity (90 %) to 5‐hydroxymethylfurfural and fructose at 140 °C in water after a reaction time of 3 h. It was recyclable and showed only a minor loss in activity after the third recycle, offering a realistic solution for the bottleneck glucose isomerization reaction for scale‐up and industrial application of biomass utilization.

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The prevalence of chronic hepatitis C virus (HCV) infection among incarcerated individuals in the United States is estimated to be between 12-31%. HCV treatment during incarceration is an attractive option due to improved access to healthcare and directly observed therapy. We compared incarcerated and non-incarcerated HCV-infected patients evaluated for treatment at a single academic center between January 1, 2002 and December 31, 2007. During this period, 521 non-incarcerated and 388 incarcerated patients were evaluated for HCV treatment. 319 (61.2%) non-incarcerated patients and 234 (60.3%) incarcerated patients underwent treatment with pegylated interferon and ribavirin. Incarcerated patients were more likely to be male, African-American race, and have a history of alcohol or intravenous drug use. Treated incarcerated patients were less likely to have genotype 1 virus and were less likely to have undergone previous treatment. There was a similar prevalence of co-infection with HIV in both groups. A sustained viral response (SVR) was achieved in 97 (42.9%) incarcerated patients compared to 115 (38.0%) non-incarcerated patients (p=0.304). Both groups had a similar proportion of patients that completed a full treatment course. Stepwise logistic regression was conducted and the final model included full treatment course, non-genotype 1 virus, younger age at treatment start, and negative HIV status. Incarceration status was not a significant predictor when added to this model (p = 0.075). Conclusion In a cohort of HCV-infected patients managed in an academic medical center ambulatory clinic, incarcerated patients were as likely to be treated for HCV and as likely to achieve an SVR as non-incarcerated patients.

Metal organic framework UiO-66 is studied as an adaptable heterogeneous catalyst for glucose conversion. UiO-66 was modified by; i) partial linker substitution, ii) particle size modulation and iii) linker defects. We studied the effect of crystallinity and functional groups on the glucose conversion and product yields. The main products are: i) fructose from the isomerisation of glucose, ii) mannose from the epimerisation of glucose and iii) 5-hydroxymethyl furfural from the dehydration of fructose. We found that defective and nano crystalline UiO-66 catalyst performs best for isomerisation. When 50 % of the linkers of UiO-66 are replaced by a sulfonate-containing linker, the catalyst shows higher isomerisation activity than other UiO-66 catalysts. Naphthalene-dicarboxylate linkers were introduced to induce hydrophobicity and this catalyst further increased isomerisation activity showing 31 % fructose selectivity. Finally, the promising catalysts were tested in a flow reactor and a bifunctional mixed linker catalyst possessing both hydrophobic and acidic functional groups is shown to be stable in a time-onstream study.

The rutiles (M,Ru)O 2 (M = Mg, Zn, Co, Ni, Cu) are formed directly under hydrothermal conditions at 240 °C from potassium perruthenate and either peroxides of zinc or magnesium or poorly crystalline oxides of cobalt, nickel, or copper. The polycrystalline powders consist of lath-shaped crystallites, tens of nanometres in maximum dimension. Powder neutron diffraction shows that the materials have an expanded a axis and contracted c axis compared to the parent RuO 2 , but there is no evidence of lowering of symmetry to other AO 2 -type structures, supported by Raman spectroscopy. Rietveld refinement shows no evidence for oxide non-stoichiometry and provides a formula (M x Ru 1−x )O 2 with 0.14 < x < 0.2, depending on the substituent metal. This is supported by energy-dispersive X-ray analysis on the transmission electron microscope, while Ru K-edge XANES spectroscopy shows that upon inclusion of the substituent the average Ru oxidation state is increased to balance charge. Variable temperature magnetic measurements provide evidence for atomic homogeneity of the mixed metal materials, with suppression of the high temperature antiferromagnetism of RuO 2 and increased magnetic moment. The new rutiles all show enhanced electrocatalysis compared to reference RuO 2 materials for oxygen evolution in 1 M H 2 SO 4 electrolyte at 60 °C, with higher specific and mass activity (per Ru) than a low surface area crystalline RuO 2 and with less Ru dissolution over 1000 cycles compared to an RuO 2 with a similar surface area. Magnesium substitution provides the optimum balance between stability and activity, despite leaching of the Mg 2+ into solution, and this was proved in membrane electrode assemblies.

A ytterbium–organic framework containing Lewis and Brønsted acid sites that effects transformation of glucose to 5-HMF in water at 140 °C.

Herein, Zeolitic imidazolate framework-8 (ZIF-8) is considered as an easy and cheap to prepare alternative catalyst for the isomerization of glucose and production of 5-hydroxymethyl furfural (HMF). For the synthesis of the ZIF-8 catalysts two preparation methods were evaluated, being room temperature and hydrothermal synthesis at 140 °C. Of these, the hydrothermal synthesis method yields a material with exceptionally high surface area (1967 m2·g−1). As a catalyst, the ZIF-8 materials generated excellent fructose yields. Specifically, ZIF-8 prepared by hydrothermal synthesis yielded a fructose selectivity of 65% with a glucose conversion of 24% at 100 °C in aqueous reaction medium. However, this selectivity dropped dramatically when the reactions were repeated at higher temperatures (~140 °C). Interestingly, greater quantities of mannose were produced at higher temperatures too. The lack of strong Brønsted acidity in both ZIF-8 materials resulted in poor HMF yields. In order to improve HMF yields, reactions were performed at a lower pH of 1.0. At 140 °C the lower pH was found to drive the reaction towards HMF and double its yield. Despite the excellent performance of ZIF-8 catalysts in batch reactions, their activity did not translate well to the flow reactor over a continuous run of 8 h, which was operating with a residence time of 6 min. The activity of ZIF-8 halved in the flow reactor at 100 °C in ~3 h, which implies that the catalyst’s stability was not maintained in the long run.