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Summary Mechanism-guided catalyst design and engineering at the scale of active sites has been developed as a powerful tool for boosting catalytic performance. Herein, we report an efficient selective silylation strategy for the elaborate fabrication of ternary Au–Ti–Si sites to boost propylene epoxidation with H2 and O2. Kinetics (isotopic) analysis, Fourier transform infrared measurements, and theoretical calculations indicate an urgent necessity for selective consuming silanol sites not only to suppress propylene oxide (PO) ring opening to byproducts promoted by H2 spillover but also to minimize PO inhibition effects. A continuous silylation treatment was developed to encourage the kinetically favorable formation of ternary Au–Ti(–OH)–Si(–O–SiR3) moiety. This delivers significantly improved H2 efficiency of 42.5% in addition to the promising PO formation rate of 193 g h−1 kgcat−1 and PO selectivity of 95.7% with the long-term stability in excess of 200 h. These insights could pave the way for rationally fabricating catalyst active sites toward optimized performance.

Uncalcined TS-1-immobilized Au bifunctional catalysts have been demonstrated to be highly active yet stable for the propylene epoxidation with H2 and O2. The objective of this study is to further e...

Classical swine fever (CSF) continues to be a devastating infectious disease for the swine industry in China and commonly exists as wild or atypical types. From June 3rd to October 3rd, 2018, outbreaks of typical CSF cases with mortality rates of 42-86% occurred in 11 swine herds in five cities of Guangdong province, and were confirmed by RT-PCR. Phylogenetic analyses based on the nucleotide sequences of full-length E2 genes showed that the CSFV isolates collected in Guangdong, 2018 grouped into sub-subgenotype 2.1c and formed a separate clade from previously identified 2.1c isolates. Sequence comparison further confirmed the distance between the novel emergent and previously identified 2.1c isolates, with shared 94.5-98.2% and 97.8-99.7% identities at the nucleotide and amino acid levels respectively. Furthermore, 2.1c isolates collected in 2018 from Guangdong province contained a unique amino acid substitution (K174R) in the E2 protein in comparison with other 2.1c representative strains and CSFV 2.1, 2.2, 2.3 strains. Of note, the novel emergent 2.1c isolates are neutralized by sera from C-strain vaccinated sows, indicating that C-strain is still efficacious for protection against field isolates of CSFV.

Yuan Wei Liau,1 Celine Cheow,1 Kenneth Tin Yau Leung,2 Hejing Tan,3 Suat Fern Low,4 Hua Heng McVin Cheen,5 Woan Chyi Lim,6 Li Ling Tan,6 Joyce Zhen Yin Tan,7 Eng Sing Lee,8 Sandra Jialun Xu,9 Corrinne Yong Koon Tan,10 Jie Wen Phang,11 Jie Kie Phang,12 Miao Hui Lam,2 Dan V Blalock,13,14Corrine I Voils,15,16Kai Zhen Yap,1 Yu Heng Kwan2,171Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, Singapore; 2Department of Pharmacy, Khoo Teck Puat Hospital, Singapore, Singapore; 3Department of Pharmacy, Woodlands Health Campus, Singapore, Singapore; 4Department of Pharmacy, Yishun Community Hospital, Singapore, Singapore; 5Department of Pharmacy, Singapore General Hospital, Singapore, Singapore; 6Department of Pharmacy, Tan Tock Seng Hospital, Singapore, Singapore; 7Department of Pharmacy, Admiralty Medical Centre, Singapore, Singapore; 8Clinical Research Unit, Family Medicine Development Division, National Healthcare Group Polyclinics, Singapore, Singapore; 9Department of Pharmacy, National Healthcare Group Polyclinics (Hougang), Singapore, Singapore; 10Pharmacy Transformation Office, National Healthcare Group Pharmacy, Singapore, Singapore; 11Department of Pharmacy, Ng Teng Fong General Hospital, Singapore, Singapore; 12Department of Rheumatology and Immunology, Singapore General Hospital, Singapore, Singapore; 13Center of Innovation to Accelerate Discovery and Practice Transformation (ADAPT), Durham Veterans Affairs Health Care System, Durham, NC, USA; 14Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA; 15Department of Surgery, University of Wisconsin School of Medicine and Public Health, Wisconsin, WI, USA; 16William S Middleton Memorial Veterans Hospital, Wisconsin, WI, USA; 17Program in Health Services and Systems Research, Duke-NUS Medical School, Singapore, SingaporeBackground: This self-report measure is a new instrument to measure the extent of and reasons for medication adherence separately. However, few studies have assessed its psychometric properties in diabetic patients and also in Asian populations.Objectives: To validate this self-report measure in diabetic patients in Singapore.Methods: We collected data prospectively using a questionnaire among 393 diabetic patients from hospitals in Singapore from July 2018 to January 2019. Using the COnsensus-based Standards for the selection of health Measurement INstruments framework, we assessed face validity, internal consistency, test–retest reliability, structural validity, and measurement error. We tested four a priori hypotheses on correlation of extent score with patient-reported outcome measures to assess construct validity. We examined cross-cultural validity via measurement invariance across gender, age groups, and languages.Results: We performed cognitive interviews with 30 consenting English-literate, Chinese-literate, and Malay-literate (10 patients per language) diabetic patients (age range 48–76 years, 53% male, disease duration range 1–30 years) and face validity was supported. Among 393 patients (mean age: 59.4±12.2 years, 50.9% female, 52.4% Chinese), we showed moderate internal consistency (Cronbach’s alpha =0.67) and test–retest reliability (intra-class coefficient=0.56 [95% CI 0.37–0.70]). We calculated smallest detectable change as 0.80. We established construct validity by meeting all four hypotheses. We showed structural validity as confirmatory factor analysis confirmed a one-factor model, with excellent fit statistics (Comparative Fit Index=1.0; Tucker-Lewis Index=1.0; Root Mean Square Error of Approximation

Understanding the nature of Au-Ti bifunctional catalysis is important yet challenging for improving direct propylene epoxidation with H2 and O2 to propylene oxide (PO). Herein, we report a facile strategy to fabricate four different crystal sized TS-1 with the presence of highly active isolated Ti4+ species by adjusting the amount of TPAOH template. The resultant uncalcined zeolite samples, i.e., TS-1-B, are employed to load Au via deposition–precipitation with urea for obtaining similar sized Au immobilized on TS-1-B catalysts and thus excluding the size effects of Au active sites. The zeolite crystal size effects are further probed, and then decreasing the crystal size gives rise to the simultaneous promotion in PO formation rate and selectivity, as well as H2 efficiency. These are attributed to the Au-Ti electronic synergy based on UV–vis and XPS measurements. The insights reported here could benefit the development of high-efficiency Au-Ti bifunctional catalysts for this reaction.

Classical swine fever (CSF) still threatens the swine industry in China, with genotype 2 isolates of CSFV dominating the epizootics. In 2018 the first E2 subunit marker vaccine against CSFV (Tian Wen Jing, TWJ-E2®), containing a baculovirus-expressed E2 glycoprotein of a genotype 1.1 vaccine strain, was officially licensed in China and commercialized. To evaluate the cross-protective efficacy of TWJ-E2 against different virulent genotype 2 Chinese field isolates (2.1b, 2.1c, 2.1 h, and 2.2), 4-week-old pigs were immunized with the TWJ-E2 vaccine according to the manufacturer’s instructions and then challenged with genotype 2 strains. A group vaccinated with the conventional C-strain vaccine was included for comparison. TWJ-E2 vaccinated pigs developed higher levels of E2 and neutralizing antibodies than those receiving the commercial C-strain vaccine. All TWJ-E2 and C-strain vaccinated pigs survived challenge without development of fever, clinical signs or pathological lesions. In contrast, all unvaccinated control pigs displayed severe CSF disease with 40–100% mortalities by 24 days post challenge. None of the TWJ-E2 and C-strain vaccinated pigs developed viremia, viral shedding from tonsils, Erns protein in the sera, or viral RNA loads in different tissues after challenge, all of which were detected in the challenged unvaccinated controls. We conclude that vaccination of young pigs with TWJ-E2 provides complete immune protection against genotypically heterologous CSFVs and prevents viral shedding after challenge, with an efficacy at least comparable to that elicited by the conventional C-strain vaccine.