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The article discusses an invention which shows a single-step process to make methyl ethyl ketone (MEK) from acetone (DMK) and methanol. It discusses several individual reactions involved in the overall MEK formation reaction, including methanol dehydrogenation to formaldehyde and hydrogen. It notes that a number of catalysts would work for the single-step conversion of acetone and methanol to methyl ethyl ketone.

The interactions of gas-phase acetone with liquid sulfuric acid solutions are described. The solutions were prepared as 0.05−0.10 μm thick films deposited on single-crystal metal substrates. Experiments were carried out over broad ranges of acid composition (70 − >96 wt % H2SO4), temperature (180−220 K), and acetone pressure (10^-7−10^-3 Pa). Two types of measurements are reported:  the time-dependent acetone uptake probability, and the infrared spectra of absorbed acetone and its reaction products. From the infrared measurements, a reaction scheme is identified in which gas-phase acetone is taken up by sulfuric acid to form protonated acetone. In solutions containing more than 70 wt % H2SO4, protonated acetone undergoes a self-condensation/dehydration reaction to form mesityl oxide. In films that contain 85 wt % or more H2SO4, a second reaction sequence occurs, ultimately resulting in the formation of trimethylbenzene. The uptake probability measurements are consistent with the infrared data. In 70 wt % H2SO4, the acetone uptake probability rapidly decreases from an initial value near unity to a steady-state value of zero, due to the formation of a saturated acetone + sulfuric acid solution. The Henry's law solubility constants of acetone in 70 wt % H2SO4 were obtained from the integrated uptake measurements. The temperature dependence of the measurements implies that the standard-state enthalpy and entropy changes of acetone solution in 70 wt % sulfuric acid are −66 kJ mol^-1 and −249 J mol^-1 K^-1, respectively. In the more concentrated films, the steady-state uptake probability is never measured to be zero, since absorbed acetone goes on to form the condensation/dehydration products. A two-step kinetic scheme is proposed to account for the reactions of acetone in sulfuric acid. By fitting the data to the model predictions, the Henry's law solubility constants and the reaction rate constants may be estimated.

High levels of natural killer (NK) cell activity and high titers of interferon were observed in the peritoneal exudate of C57BL/6 mice 20 to 50 h after injection of mouse hepatitis virus type 3 (MHV3) but not during the first 10 h after infection. C57BL/6 mice were susceptible to MHV3 infection and showed high titers of MHV3 in the peritoneal exudate 48 h after infection. A/J mice, in contrast, were resistant to the dose that killed 100% of the C57BL/6 mice (10 macrophage-infecting doses) and showed considerably lower virus titers than those shown by C57BL/6 mice. NK cell activity and interferon titers were significantly lower in the peritoneal exudate of A/J mice than in that of C57BL/6 mice. Serum interferon titers were also lower in A/J mice. Thus, our data show an inverse relationship between resistance and the levels of these two parameters. The data suggest that, in contrast to the situation observed with certain herpesviruses, interferon and NK cells may not be of overwhelming importance in the defense of mice against MHV3.

C57BL/6 mice that are highly susceptible to infection with mouse hepatitis virus type 3 were protected against intraperitoneal viral infection by simultaneous intraperitoneal injection of Corynebacterium parvum. No protection was observed when C. parvum was given intravenously or when it was injected intraperitoneally 3 days before viral infection. Protective effects were, however, consistently found when C. parvum was given 2 h before or 2 h after viral infection. Activity was seen only against 10 50% lethal doses and not against 100 50% lethal doses. C. parvum also caused a significant decrease of virus type 3. These data suggest a direct effect of C. parvum on virus-susceptible cells. Injection of C. parvum in mice caused activation of natural killer (NK) cells and of interferon production. However, these two effects were equally demonstrable at high and low doses of C. parvum, whereas protection against mouse hepatitis virus type 3 was not demonstrable at low doses of C. parvum. Thus, antiviral protection may be dissociated from activation of NK cells and induction of interferon.

Non-detectable (ND) and outlying concentration values (OV) are a common challenge of biomarker investigations. However, best practices on how to aptly deal with the affected cases are still missing. The high methodological heterogeneity in biomarker-oriented research, as for example, in the field of psychoneuroendocrinology, and the statistical bias in some of the applied methods may compromise the robustness, comparability, and generalizability of research findings. In this paper, we describe the occurrence of ND and OV in terms of a model that considers them as censored data, for instance due to measurement error cutoffs. We then present common univariate approaches in handling ND and OV by highlighting their respective strengths and drawbacks. In a simulation study with lognormal distributed data, we compare the performance of six selected methods, ranging from simple and commonly used to more sophisticated imputation procedures, in four scenarios with varying patterns of censored values as well as for a broad range of cutoffs. Especially deletion, but also fixed-value imputations bear a high risk of biased and pseudo-precise parameter estimates. We also introduce censored regressions as a more sophisticated option for a direct modeling of the censored data. Our analyses demonstrate the impact of ND and OV handling methods on the results of biomarker-oriented research, supporting the need for transparent reporting and the implementation of best practices. In our simulations, the use of imputed data from the censored intervals of a fitted lognormal distribution shows preferable properties regarding our established criteria. We provide the algorithm for this favored routine for a direct application in R on the Open Science Framework (https://osf.io/spgtv). Further research is needed to evaluate the performance of the algorithm in various contexts, for example when the underlying assumptions do not hold. We conclude with recommendations and potential further improvements for the field.