The acquisition of Cantonese classifiers by preschool children in Hong Kong

The Cantonese language has a complex classifier system and young learners need to pay attention to both the semantics and syntax of classifiers. This study investigated the repertoire of classifiers produced by 492 Cantonese-speaking preschoolers in three age groups (3 ;0, 4 ;0 and 5 ;0). Spontaneous utterances produced in 30-mmute toy-play contexts were collected and transcribed. Analyses identified a productive repertoire of 73 classifiers in the utterances, which could be appropriately classified into the typology proposed in the present study. An age-related increase in the number of classifier types per child as well as the repertoire size of each group was found. g03 (CL) was widely used as the general classifier by the young children. It was also discovered that the three-year-olds were already showing signs of grasping the basic syntax of classifiers. Cognitive, linguistic and contextual influences presumed to shape the evidence are discussed. © 2007 Cambridge University Press.published_or_final_versio

Electrochemical degradation of 4-chlorophenol at nickel-antimony doped tin oxide electrode

The effectiveness of a novel nickel-antimony doped tin oxide electrode for electrochemical degradation of organic pollutants was investigated using 4-chlorophenol (4-CP) as a model toxic organic. The experimental results demonstrate that the optimal Ni content was at Ni:Sn = 1:500 in atomic ratio in the precursor coating solution, whereas the Sb:Sn ratio was set at 8:500. Using the electrode prepared with the optimal Ni doping ratio for 4-CP degradation, the charge-based efficiencies were up to 89 μg C -1 for 4-CP destruction and 15 μg C -1 for TOC removal, which were considerably higher than the efficiencies observed for other electrodes. It is suggested that the enhancement of the electrode for electrochemical oxidation of organics could be attributed to the production of hydroxyl radicals in anodic water electrolysis. © 2006 Elsevier Ltd. All rights reserved.postprin

Vitamin B12 levels in patients with type 2 diabetes mellitus on metformin

Background: Due to the clinical benefits of metformin, its associated side effects such as vitamin B12 deficiency are usually overlooked and rarely investigated.Objective: This study was carried out to determine the serum level of vitamin B12 in Nigerian patients with type 2 diabetes mellitus (T2DM) on metformin.Methods: Serum vitamin B12 level was determined using high performance liquid chromatography (HPLC) in 81 T2DM patients who have been on metformin for 5 years or more. Vitamin B12 deficiency was defined as serum concentration of <200 pg/dl, borderline deficiency as 200 – 300 pg/dl and >300 pg/dl as normal. Differences in vitamin B12 levels between different groups were assessed using Mann Whitney U test and P<0.05 was considered as statistically significant.Results: Vitamin B12 deficiency and borderline deficiency were recorded in 8.6% and 26.0% of the patients respectively. Vitamin B12 level was significantly lower in patients who have been on metformin for  ≥10 years compared with patients with <10 years history of metformin use. Similarly, patients who were on metformin at a dose of >1000 mg/day had significantly lower vitamin B12 level when compared with patients on ≤1000 mg/day.Conclusion: Low serum vitamin B12 level is associated with longer duration and higher dose of metformin use. Therefore, routine determination of vitamin B12 level in patients with T2DM on high dose of metformin and those with prolonged use of metformin might help in identifying patients that would benefit from vitamin B12 supplements.Keywords: Metformin, Type 2 diabetes mellitus, Vitamin B12 deficienc

Asking for action or information? Crosslinguistic comparison of interrogative functions in early child Cantonese and Mandarin

Request for information (RfI) is believed to be the universally dominant function of young children’s questioning, whereas request for action (RfA) has been reported to be the leading interrogative form used in early child Cantonese. The possibility of crosslinguistic variability prompts further research and comparison with additional languages. This study compares the interrogatives elicited from two early Chinese language corpora: Early Childhood Cantonese Corpus (ECCC) and Early Childhood Mandarin (ECMC). Altogether, 1214 and 942 question types were elicited from ECCC and ECMC, respectively. Analyses indicated that: (1) all the interrogative functions identified in an earlier study of Cantonese were also observed in the early Mandarin interrrogatives; and (2) both RfA (49.9%) and RfI (45.5%) were the most frequently observed functions of early child Chinese interrogatives. This crosslinguistic evidence suggests that follow-up studies are needed to further explore the possible influences of language, culture and communication tasks on children’s uses of interrogative forms.postprin

Hole-transporting spirothioxanthene derivatives as donor materials for efficient small-molecule-based organic photovoltaic devices

Poster: no. 30Taking the advantages of the 3D structure and rigid spiro-conjugation, spirobifluorene and its derivatives are a benchmark class of p-type semiconductors in organic electronic devices because of their good charge-transporting properties. However, their low absorption coefficients within the visible spectrum render their application as photoactive materials in the fabrication of organic photovoltaic (OPV) devices. A new class of heterocyclic spirothioxanthene derivatives has been designed and synthesized by the functionalization of the spiro core with various triarylamine groups and the modification of the heteroatom of the spiro core. The photophysical, electrochemical and thermal properties of these spirothioxanthene derivatives have been fully characterized. Of particular interest, all of these compounds exhibit high hole mobilities of up to 10–3 cm2V–1s–1, as determined from thin film transistor measurement. More importantly, these spirothioxanthene derivatives are promising donor materials for the fabrication of high performance OPV devices. With a very low dopant concentration of 7 % doped into fullerene matrix, efficient small molecular-based OPV devices with high open-circuit voltage of 0.94 V and high power conversion efficiency of 5.40 % (the highest PCE of 5.46 %) have been realized. This demonstrates for the first time their application studies as photovoltaic donor materials in OPV devices.published_or_final_versio

Amorphous Mixtures of Ice and C₆₀ Fullerene

Carbon and ice make up a substantial proportion of our universe. Recent space exploration has shown that these two chemical species often coexist such as on comets and asteroids and in the interstellar medium. Here, we prepare mixtures of C60 fullerene and H2O by vapor codeposition at 90 K with molar C60/H2O ratios ranging from 1:1254 to 1:5. The C60 percolation threshold is found between the 1:132 and 1:48 samples, corresponding to a transition from matrix-isolated C60 molecules to percolating C60 domains that confine H2O. Below this threshold, the crystallization and thermal desorption properties of H2O are not significantly affected by C60, whereas the crystallization temperature of H2O is shifted toward higher temperatures for the C60-rich samples. These C60-rich samples also display exotherms corresponding to the crystallization of C60 as the two components undergo phase separation. More than 60 vol % C60 is required to significantly affect the desorption properties of H2O. A thick blanket of C60 on top of pure amorphous ice is found to display large cracks due to water desorption. These findings may help us to understand the recently observed unusual surface features and the H2O weather cycle on the 67P/Churyumov–Gerasimenko comet

Knowledge, attitudes, and willingness of healthcare workers in Iraq’s Kurdistan region to vaccinate against human monkeypox: a nationwide cross-sectional study

Although human monkeypox infections had not been recorded in the Kurdistan region of Iraq as of August 2023, the rapid growth of cases worldwide and the detection of monkeypox in neighboring Middle Eastern nations call for careful planning and timely response measures. Educating and empowering frontline healthcare workers (HCWs) so that they can act to curb the spread of monkeypox infections are core elements of primary prevention and protecting public health. Therefore, this study aimed to assess HCWs’ knowledge and attitudes about monkeypox and their willingness to vaccinate against monkeypox. By employing a convenience sampling method, an online survey was disseminated via Google Forms between 1 November 2022 and 15 January 2023. The researchers utilized regression analyses to ascertain the factors associated with the three parameters: knowledge, attitude, and the willingness to vaccinate. A total of 637 HCWs were included in the analysis (ages ranged between 21 and 51 years). The mean overall scores were 8.18 of a max score of 16 (SD 3.37), 3.4 of 5 (SD 1.37), and 2.41 of 5 (SD 1.25) for knowledge, attitude, and willingness to vaccinate, respectively. A multivariate logistic regression analysis demonstrated that HCWs who had heard about monkeypox before 2022 rather than later had a higher level of knowledge (AOR: 4.85; 95% CI: 2.81–8.36; p < 0.001). In addition, those who had newly joined the workforce or had less than 1 year experience in practice had more positive attitudes about curbing monkeypox (AOR: 0.35; 95% CI: 0.20–0.59; p < 0.01) than those who practiced for longer. No significant predictors of willingness to vaccinate against monkeypox were identified. The research revealed that HCWs exhibited a relatively low level of monkeypox knowledge. They also had poor attitudes towards monkeypox vaccination and were therefore reluctant to receive the vaccines. Imparting knowledge about the infectious disease can cultivate better awareness and attitudes among HCWs as to their roles in mitigating the spread of an epidemic in the foreseeable future

Knowledge and Perceptions on Malaria and Its Association with Aquatic Habitats

Background: Malaria remains the major cause of morbidity and mortality among children in Kenya. About 70 percent of the population is at risk of infection, and roughly 34,000 young children die of malaria-related causes annually.Objective: To investigate the knowledge and perceptions of the local people for malaria in relation to aquatic habitats along the Kenyan Lake Victoria basin.Design: Community-based cross-sectional study.Setting: The Kenyan Lake Victoria basin Region.Subjects: Two hundred and fourty three individuals (both women and men residing in the beaches and surrounding areas) were interviewed about their knowledge and perceptions regarding malaria.Results: Mosquitoes were perceived to be the main cause of malaria. Most respondents were familiar with the main signs and symptoms of mild malaria. Majority of the respondents had poor knowledge of mosquito breeding habitats with 45% mentioning the lake and only 18.6 and 8.9% mentioning ponds and dams, respectively. Most female respondents did not know the difference between mosquitoes and lake flies, P=0.03, Fishers exact test. The majority (97.5%) of the respondents reported seeking conventional malaria treatment from health institutions.Conclusion: Mosquitoes are perceived to be the main cause of malaria by both males and females. A significant proportion of the respondents were familiar with the main signs and symptoms of malaria and sought conventional medicine for treatment of the disease. Most of the respondents, however, had poor knowledge on the breeding habitats of mosquitoes. Concerted effort is needed to scale-up health education and improve the knowledge of the community about mosquitoes and their breeding habitats, particularly malaria vectors which do not breed in deep lake waters. Effective anti-malarial drugs should also be available at the grassroots level where the problem of malaria is rampant

Community perceptions of schistosomiasis transmission, prevalence and control in relation to aquatic habitats in the Lake Victoria basin of Kenya

Background: Intestinal schistosomiasis caused by Schistosoma mansoni and urinary schistosomiasis caused by Schistosoma haematobium are widely distributed parasites in several localities of the Lake Victoria basin of Kenya, the former being more prevalent. In Kenya, transmission of the intestinal form of bilharzia (S. mansoni) tends to be closely confined to narrow zones along the shores of large bodies of water such as Lake Victoria where it is endemic and the intermediate host is found. The prevalence of S. mansoni along the Kenyan Lake Victoria basin ranges between 40% and 80%.Objective: To assess the community’s knowledge and perceptions of schistosomiasis prevalence, transmission and control in relation to aquatic habitats in the Lake Victoria basin of Kenya.Design: Community-based cross-sectional study.Setting: The Kenyan Lake Victoria basin.Subjects: Two hundred and forty three individuals (both women and men residing in the beaches and surrounding areas) were interviewed about their knowledge and perceptions regarding schistosomiasis.Results: The community regarded schistosomiasis as a naturalistic disease not caused by supernatural forces but by an agent of contamination in water. Knowledge on schistosomiasis transmission and control was low, with 42% of the respondents having no idea on how schistosomiasis is contracted, while 22% and 18% of the respondents mentioned contact with contaminated water and drinking / eating dirty water / food, respectively. Most respondents were familiar with the snails’ habitats, but had poor knowledge on aquatic plants harbouring snails, as 57% of the respondents did not know about aquatic plants being associated with schistosomiasis snails. Only 3% of the respondents associated snails with schistosomiasis transmission. Sixty percent (60%) of the respondents mentioned use of tablets and injections as means of treating schistosomiasis, while 38% had no idea how it is treated and 2% mentioned use of local herbs and services of medicine men.Conclusion: Majority of Kenyan Lake Victoria basin inhabitants had little awareness about schistosomiasis despite high prevalence of the disease in the region. There is need to adapt prevention and control strategies to the people’s livelihoods. There is also need to target the less advantaged members of the community such as women, uneducated and subsistence farmers for intense health education strategies aimed at increasing participation in the control of schistosomiasis. Study to elicit divergence between biomedical and local understandings of schistosomiasis/bilharzia is suggested.