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Pangolins are considered difficult to maintain in zoos, often attributed to problems in feeding management. Taipei Zoo's designation as a wildlife rescue center for Chinese pangolins (Manis pentadactyla) has resulted in long term feeding experience with development of diets that support recovery, maintenance, and reproduction, as well as experimental opportunities to further understand digestive physiology to optimize nutrition. Opportunistic dissection of 10 animals revealed details of the tongue, salivary glands, stomach and gastrointestinal tract (GIT), including confirmation of anatomical differences between Asian and African pangolin species. Length of the total GIT relative to body length (∼ 9:1) was greater than found in domestic carnivores, more similar to omnivorous species. Intake and digestion trials conducted with 4 animals demonstrated that pangolins maintained body weights (BW; 6–9 kg) consuming diets containing 32–40% crude protein, 20–25% crude fat, and 13–28% crude fiber (DM basis). Daily DM intakes ranged from ∼40 to 70 g per animal, with digestible energy intake 51.5–87.5 kcal /kg BW0.75/day; pangolins consumed 9.4–15.2 g DM/kg BW0.75/day. Dietary energy data support observations of low metabolism and maintenance requirements for this species, similar to values reported for other myrmecophageous species. Addition of 5% ground chitin to diets improved fecal consistency, and decreased digestibility of DM, protein, and energy; addition of chitosan (chitin treated with NaOH) resulted in diet rejection. This information may assist in enhancement of captive diets, as well as in controlling obesity in pangolins. Zoo Biol. 34:262–270, 2015. © 2015 Wiley Periodicals Inc.

Using a membrane reactor for reversible transesterification reaction involves reaction and product separation within a single unit. However, a pseudohomogeneous reaction and heterogeneous separation must be maintained for successful membrane reactor operation. Present research is aimed to develop an integrated model of chemical and phase equilibrium (CPE) and modified Maxwell–Stefan equation that describes the simultaneous CPE and mass transport phenomena of biodiesel production from crude palm oil (CPO) using a membrane reactor. In the first part of this work, a systematic approach describing simultaneous CPE of CPO transesterification in the membrane reactor was developed with the reconciliation of transesterification reaction and phase equilibrium that involves six-component. The results revealed that regressed apparent equilibrium constant, Keq value of 17.557 ±1.51% were higher than the literatures. This indicates that forward reaction of the reversible CPO transesterification is much favored in the membrane reactor than the conventional reactor. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1968–1980, 2015

The mechanistic modeling of biodiesel production process in membrane reactor with the consideration of chemical reaction, phase equilibrium, and ultrafiltration is important for the membrane reactor design. In part II of this work, the chemical and phase equilibrium (CPE) model for crude palm oil transesterification reaction in the membrane reactor developed in part I is extended to an integration of CPE with modified Maxwell–Stefan model, which considers multicomponent mass transport phenomena of concentration polarization and intramembrane. A good fit of simulated permeate fluxes and apparent solute rejection to the experimental data shows that the model has a good prediction capability. Reversible fouling was found to be the major fouling and no pore plugging was observed. Simulation results verified that micelles were retained by the membrane at CPO:MEOH molar ratio of 1:24 and catalyst concentration of 0.5 wt %. However, phase inversion happened when catalyst concentration of 0.05 and 0.1 wt % were used. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1981–1996, 2015

Synthesis of 3-fluoro-2-hetarylindoles through addition of hetarenes to 3,3-difluoroindolium ions generated in situ by Zn(OTf)2-catalyzed oxazolidine ring opening is described. Indoles, pyrroles and alkyl-substituted furans can be used as hetaryl nucleophiles to afford a range of 3-fluoro-2-hetarylindole products 6 in 56–95 % yields. A diverse array of 3,3-difluorinated 2-hetarylindolines 7 can also be synthesized in 43–84 % yields by a tandem sequential process that involves hetarene nucleophilic addition, HF elimination and fluorocyclization reactions. Our study by 1H NMR and UV/Vis spectroscopy reveals that 3,3-difluorinated 2-hetarylindolines possess interesting substituent-dependent acidochromic properties. UV absorption and fluorescence spectra of selected compounds 6 and 7 are also studied.

Background: Hyperkalaemia has been reported with high-dose trimethoprim (20 mg/kg/day) and standard-dose trimethoprim (6 mg/kg/day) plus sulfamethoxazole use. Aim: To investigate changes in plasma potassium concentrations in patients prescribed standard-dose trimethoprim 300 mg daily for urinary tract infections. Method: A retrospective cohort study of hospital patients with urinary tract infections treated with trimethoprim or other antibacterials (control group) for more than 5 days. Plasma potassium concentration, creatinine and urea were compared at baseline and at the completion of treatment. Results: There were 31 patients in the trimethoprim group and 65 patients in the control group. End-of-therapy mean plasma potassium concentrations increased significantly from baseline in the trimethoprim group (4.2 plus or minus 0.4 mmol/L to 4.5 plus or minus 0.5 mmol/L; p = 0.002) but not in the control group. End-of-therapy mean plasma potassium concentrations were also higher in the trimethoprim group (4.5 plus or minus 0.5 mmol/L vs 4.2 plus or minus 0.5 mmol/L; p = 0.007). 65% of the trimethoprim group developed end-of-therapy hyperkalaemia versus 39% of the control group. Mean creatinine concentration in the trimethoprim group increased by an average of 21% from baseline but did not change in the control group. The trimethoprim group showed no change in mean urea concentration but a decrease was noted in the control group. Conclusion: Treating urinary tract infections with trimethoprim 300 mg daily for more than 5 days was associated with an increase in plasma potassium concentration.

A scalable procedure for the title transformation of a broad range of α,α-disubstituted carboxylic esters is developed which delivers the products in often very high yields and with very high enantiomeric purity.

Recently, membrane reactor technology was used to produce high-quality biodiesel because of its advantage of simultaneous transesterification and separation. As the transesterification reaction involves two immiscible phases of methanol (MeOH) and oil (TG), a thorough investigation on the membrane reactor for biodiesel production with the consideration of chemical phase equilibrium (CPE) via modeling analysis, was conducted in this study. A mathematical model was developed based on the modified Maxwell-Stefan model with the incorporation of CPE. The formation of TG rich micelles dispersed in the continuous phase of MeOH was the most important hypothesis in the model development. The preliminary experiment results show that the permeate compositions from the membrane reactor were closely related to CPE of the system, which was highly depending on the MeOH to TG molar ratio. TG free permeate can only be obtained if the continuous phase of MeOH was free from TG and the TG rich micelles were retained by the membrane. The model verification further confirmed the formation of micelles dispersed in the continuous MeOH phase within the feed side of the membrane reactor and the model was able to predict the performance of the membrane reactor for biodiesel production at an acceptable accuracy. © 2012 American Institute of Chemical Engineers AIChE J, 59: 258–271, 2013

Background—Coffee consumption has been shown to be inversely associated to type 2 diabetes mellitus (T2DM), but evidence in Chinese populations is limited. We investigated the relationship between coffee consumption and T2DM in a population-based cohort of middle-aged Chinese. Materials and Methods—We studied 2,332 subjects who participated in the Taichung Community Health Study in Taiwan in 2004. The relationships between coffee consumption, T2DM and fasting glucose were assessed. Results—The prevalence of T2DM was 14.0% and 10.4% in men and women. After adjustment for age, body mass index, blood pressure, smoking, alcohol drinking, betel nut chewing, physical activity, income, education level, fat%, protein%, carbohydrate%, and magnesium, coffee intake was inversely associated with T2DM. Habitual coffee drinkers had 38–46% lower risk of T2DM than non-drinkers. Compared to non-drinkers, the adjusted odds ratios (ORs) for T2DM according to subjects with habitual coffee consumption (

The synthesis of various 3-fluoro-2-hetarylindoles through addition of indoles, pyrroles, or alkyl-substituted furans to 3,3-difluoroindolium ions generated in situ by zinc triflate-catalyzed oxazolidine ring opening is described.

The stability of unsaturated fatty acids to oxidation was monitored by following gas chromatographic (GC) analyses of headspace volatiles in comparison to changes in polyunsaturated fatty acids (PUFA) and increases in malonaldehydevia the 2-thiobarbituric (TBA) assay. Pure standards of linoleic acid (Lo) and n-3 fatty acids [eicosapentaenoic (EPA) and docosahexaenoic acid (DHA)] were added to headspace vials, equilibrated in air for 10 min, followed by heating at 80°C in teflon-capped vials for different time intervals. Headspace analysis showed increases in acetaldehyde, propenal, and propanal, corresponding to the oxidation of n-3 fatty acids, whereas hexanal production corresponded to losses of linoleic acid. The analysis of propanal by GC-headspace after only five minutes of heating appeared to be the most effective method of monitoring the oxidation of n-3 fatty acids, as indicated by correlations between TBA values and loss of PUFA. The oxidation of Lo, EPA and DHA appeared to be a function of the number of double bonds. Correlations between PUFA depletion, TBA values and volatile formation indicate that under the prescribed conditions of this experiment, GC-headspace analysis of propanal and pentane/hexanal is an excellent method for following the oxidation of selected n-3 fatty acids and linoleic acid.

The photolysis of ethyl 5-oxo-2-phenyl-2,5-dihydroisoxazole-4-carboxylate in acetonitrile containing 0.5% tri- fluoroacetic acid in the presence of thioamides gives moderate (40–60%) yields of thiazole-5-carboxylate esters. In the absence of trifluoroacetic acid, the intermediate vinyl thioesters can be isolated. That addition of the thioamide to the first formed carbene was, through sulfur, confirmed by X-ray crystal structures of 2-methylthiazole-5-carboxylic acid and a byproduct.