Delocalized hypervalent silyl radical supported by amidinate and imino substituents

The reaction of the amidinato silylsilylene with a functionalized diaminochlorosilyl substituent [LSiSi(Cl){(NtBu)2C(H)Ph}] (1, L = PhC(NtBu)2) with ArN=C=NAr (Ar = 2,6-iPr2C6H3) in toluene afforded the delo-calized hypervalent silyl radical [LSi(-CNAr)2Si{(NtBu)2C(H)Ph}] (2). It possesses a hypervalent silyl radical, which delocalizes throughout the Si2C2 ring

Dyslexia-related loci are significantly associated with language and literacy in Chinese–English bilingual Hong Kong Chinese twins

This study was partially funded by the Research Grants Council of the Hong Kong Special Administration Region (C4054-17WF) and the Theme-based Research Scheme from the Hong Kong Special Administrative Region Research Grants Council (T44-410/21-N).A recent genome-wide association study on dyslexia in 51,800 affected European adults and 1,087,070 controls detected 42 genome-wide significant single nucleotide variants (SNPs). The association between rs2624839 in SEMA3F and reading fluency was replicated in a Chinese cohort. This study explores the genetic overlap between Chinese and English word reading, vocabulary knowledge and spelling, and aims at replicating the association in a unique cohort of bilingual (Chinese–English) Hong Kong Chinese twins. Our result showed an almost complete genetic overlap in vocabulary knowledge (r2 = 0.995), and some genetic overlaps in word reading and spelling (r2 = 0.846, 0.687) across the languages. To investigate the region near rs2624839, we tested proxy SNPs (rs1005678, rs12632110 and rs12494414) at the population level (n = 305–308) and the within-twin level (n = 342–344 [171–172 twin pairs]). All the three SNPs showed significant associations with quantitative Chinese and English vocabulary knowledge (p PostprintPeer reviewe

Hong Kong dentists' preparedness for medical emergency in dental clinics

Aim: The aim of this study was to investigate the Hong Kong dentists’ and dental clinics’ preparedness for medical emergency in the dental clinic. Methods: Two custom designed questionnaires were developed, one for dentists and another for dental clinics, to collect the required information. The sampling frame for participants was the list of registered dentists published by the Hong Kong Dental Council on its website in January 2016. A total of 434 dentists and 143 dental clinics were selected from the list by systematic random sampling. The latter sample was supplemented by 10 randomly selected government dental clinics. The questionnaires were mailed the selected dentists together with a cover letter and a stamped return envelope. A reminder letter and another copy of the questionnaire were sent out two weeks after the first mailing. Results: 167 (38%) completed dentist questionnaires and 53 (35%) clinic questionnaires were collected. Most of the respondent dentists had some deficient knowledge on basic life support (BLS), their mean score was 3.5 out of a maximum of 5. Most (>60%) of the respondents thought they were competent in performing medical emergency procedures except giving intravenous injection. Moreover, most (>60%) of them held positive attitude towards having immediate availability of essential medical emergency equipment and drugs in their clinic. Dentists who were more recent graduates, those with postgraduate qualifications, and those who work with accompaniment generally had higher mean BLS knowledge scores. In the dental clinics, the most commonly kept medical emergency equipment/drug was instant glucose (70%) and followed by antihistamine (62%). Only a quarter of the clinics were equipped with AED, and 45% were equipped with oxygen cylinder. For 8 out of the 11 items, a higher proportion of the bigger clinics (>2 dental chairs) than the smaller clinics had the medical emergency equipment/drug available (Chi-square test, p<0.05). Conclusion: Hong Kong dentists have a moderate level of knowledge on BLS which should be enhanced through regular attendance at CE courses. Their knowledge level is affected by a number of their background and professional activities factors. Most dental clinics in Hong Kong have only few of the essential medical emergency equipment and drugs while the larger clinics are better equipped than the smaller clinics.published_or_final_versio

Genome of the rams horn snail Biomphalaria straminea : an obligate intermediate host of schistosomiasis

This work was supported by the Hong Kong Research Grant Council Collaborative Research Fund (C4015-20EF), General Research Fund (14100919), NSFC/RGC Joint Research Scheme (N_CUHK401/21), and The Chinese University of Hong Kong Direct Grant (4053433, 4053489). Y.Y., W.L.S., C.F.W., S.T.S.L., and Y.L. were supported by the Ph.D. studentships of The Chinese University of Hong Kong. A.H. is supported by a Biotechnology and Biological Sciences Research Council (BBSRC) David Phillips Fellowship (BB/N020146/1). T.B. is supported by a studentship from the Biotechnology and Biological Sciences Research Council-funded South West Biosciences Doctoral Training Partnership (BB/M009122/1). M.E.A.R. is supported by a Ph.D. studentship from the School of Biology and St Andrews University.Background: Schistosomiasis, or bilharzia, is a parasitic disease caused by trematode flatworms of the genus Schistosoma. Infection by Schistosoma mansoni in humans results when cercariae emerge into water from freshwater snails in the genus Biomphalaria and seek out and penetrate human skin. The snail Biomphalaria straminea is native to South America and is now also present in Central America and China, and represents a potential vector host for spreading schistosomiasis. To date, genomic information for the genus is restricted to the neotropical species Biomphalaria glabrata. This limits understanding of the biology and management of other schistosomiasis vectors, such as B. straminea. Findings: Using a combination of Illumina short‐read, 10X Genomics linked‐read, and Hi‐C sequencing data, our 1.005 Gb B. straminea genome assembly is of high contiguity, with a scaffold N50 of 25.3 Mb. Transcriptomes from adults were also obtained. Developmental homeobox genes, hormonal genes, and stress-response genes were identified, and repeat content was annotated (40.68% of genomic content). Comparisons with other mollusc genomes (including Gastropoda, Bivalvia, and Cephalopoda) revealed syntenic conservation, patterns of homeobox gene linkage indicative of evolutionary changes to gene clusters, expansion of heat shock protein genes, and the presence of sesquiterpenoid and cholesterol metabolic pathway genes in Gastropoda. In addition, hormone treatment together with RT-qPCR assay reveal a sesquiterpenoid hormone responsive system in B. straminea, illustrating that this renowned insect hormonal system is also present in the lophotrochozoan lineage. Conclusion: This study provides the first genome assembly for the snail B. straminea and offers an unprecedented opportunity to address a variety of phenomena related to snail vectors of schistosomiasis, as well as evolutionary and genomics questions related to molluscs more widely.Publisher PDFPeer reviewe

Towards a global partnership model in interprofessional education for cross-sector problem-solving

Objectives A partnership model in interprofessional education (IPE) is important in promoting a sense of global citizenship while preparing students for cross-sector problem-solving. However, the literature remains scant in providing useful guidance for the development of an IPE programme co-implemented by external partners. In this pioneering study, we describe the processes of forging global partnerships in co-implementing IPE and evaluate the programme in light of the preliminary data available. Methods This study is generally quantitative. We collected data from a total of 747 health and social care students from four higher education institutions. We utilized a descriptive narrative format and a quantitative design to present our experiences of running IPE with external partners and performed independent t-tests and analysis of variance to examine pretest and posttest mean differences in students’ data. Results We identified factors in establishing a cross-institutional IPE programme. These factors include complementarity of expertise, mutual benefits, internet connectivity, interactivity of design, and time difference. We found significant pretest–posttest differences in students’ readiness for interprofessional learning (teamwork and collaboration, positive professional identity, roles, and responsibilities). We also found a significant decrease in students’ social interaction anxiety after the IPE simulation. Conclusions The narrative of our experiences described in this manuscript could be considered by higher education institutions seeking to forge meaningful external partnerships in their effort to establish interprofessional global health education

Synthesis of a dimeric phosphine-stabilized phosphidogermanium(I)-amidogermanium(II) derivative

The synthesis of a dimeric phosphine-stabilized phosphidogermanium(I)-amidogermanium(II) derivative is described. The reaction of amidinato phosphinoamidosilylene [L{(Ar)(Ph₂P)N}Si:] (1, L = PhC(NtBu)₂, Ar = 2,6-iPr₂C₆H₃) with GeCl₂·dioxane afforded a phosphine-stabilized phosphidogermanium(i) dimer moiety in a mixed-valent germanium(I,II) compound [:Ge(Cl){N(Ar)PPh₂}(Ph₂P)Ge:]₂ (3). The mechanism for the formation of 3 is also studied and reported.Ministry of Education (MOE)This work is supported by AcRF Tier 1 grant (RG 15/15)

A base-stabilized silylene-promoted C(sp³)-H borylation and H₂ activation

Treatment of the amidinato amidosilylene [L{(Me3Si)2N}Si:] [1, L = PhC(NtBu)2] with a slight excess of borane-tetrahydrofuran complex [BH3·THF] in toluene at room temperature afforded the silylene-borane adduct [L{(Me3Si)2N}Si:→BH3] (2). A triflate substituent was introduced on the boron center by reacting 2 with methyl triflate [MeOTf] (OTf = OSO2CF3) in toluene at room temperature to form [L{(Me3Si)2N}Si:→BH2OTf] (3), with the elimination of CH4 gas. The intramolecular C(sp3)-H borylation and H2 elimination occurred by reacting complex 3 with 1 in refluxing toluene to form a C-B bond in the resulting silylene-boronium ion 5. Complex 5 activated H2 gas or NH3BH3 at room temperature to form silylene-borane adduct 2 and [L{(Me3Si)2N}Si-H]OTf. Additionally, the reaction of 5 with H2 was studied through density functional theory calculations.Agency for Science, Technology and Research (A*STAR)Ministry of Education (MOE)National Research Foundation (NRF)Accepted versionThis work is supported by an ASTAR SERC PSF grant (1421200081), the Ministry of Education, Academic Research Fund Tier 1 (RG 121/17), and the National Research Foundation Singapore NRF-ANR (NRF2018-NRF-ANR026 Si-POP)

Reactivity of digermylenes toward potassium graphite : synthesis and characterization of germylidenide anions

The synthesis and characterization of the digermylenes [LGe–GeL] [L = L1 (3A), L2 (3B)] supported by the 2,6-diiminophenyl (L1) and 2-imino-5,6-methylenedioxylphenyl (L2) ligands are described. Their reactivities toward potassium graphite are also reported. The reaction of [LGeCl] [L = L1 (2A), L2 (2B)] with KC8 in tetrahydrofuran (THF) at room temperature afforded the digermylenes [LGe–GeL] [L = L1 (3A), L2 (3B)], which are the first examples of diaryldigermylenes stabilized by o-imino donor(s). The treatment of 3A with 2 equiv of KC8 in Et2O, followed by the addition of excess tetramethylethylenediamine (TMEDA), results in cleavage of the GeI–GeI bond to afford the germylidenide anion [L1GeK·TMEDA] (4A). Similarly, the reaction of 3B with excess KC8 in THF afforded the germylidenide anion [L2GeK] (4B). The molecular structures of compounds 4A and 4B as determined by single-crystal X-ray diffraction analysis show that the K atoms are η1-coordinated with the low-valent Ge atoms. Moreover, the negative charges at the Ge atoms in compounds 4A and 4B are stabilized by electron delocalization in the germanium heterocycles

Synthesis of a base-stabilized silicon(I)-iron(II) complex for hydroboration of carbonyl compounds

The reaction of the amidinatosilicon(I) dimer [LSi:]2 (1; L = PhC(N tBu)2) with FeBr2 in tetrahydrofuran (THF) at ambient temperature afforded the silicon(I)-iron(II) dimer [LSi(FeBr2·THF)]2 (2) after 40 h. Compound 2 can catalyze hydroboration of aliphatic and aromatic ketone compounds with HBpin in the absence of any strong reducing agent. Mechanistic studies show that complex 2 reacts with ketone compounds to form a zwitterionic intermediate in the first step of catalysis. Subsequent reaction with HBpin affords the corresponding boron esters and then regenerates complex 2.ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio

Reactivity of a distannylene toward potassium graphite : synthesis of a stannylidenide anion

The synthesis and characterization of the stannylidenide anion [LSn:]− (L = 2,6-(CH═NBut)2C6H3) supported by the 2,6-diiminophenyl ligand is described. The reaction of the chlorostannylene [LSnCl] (2) with excess KC8 in diethyl ether at room temperature afforded the distannylene [LSn:]2 (3). The treatment of 3 with 2 equiv of KC8 in tetrahydrofuran (THF) resulted in the cleavage of the SnI–SnI bond in 3 to afford the potassium stannylidenide [LSnK·THF] (4). The molecular structure of compound 4 as determined by single-crystal X-ray diffraction analysis shows that the K atom is η5-coordinated to the low-valent tin heterocycle. Moreover, the negative charge at the Sn atom in compound 4 is stabilized by an electron delocalization in the low-valent tin heterocycle