Geoboard activities for the learning and teaching of shape and space: revisiting the theories and reviewing the practical designs

Conference Theme: Nurturing Mathematical Thinkingno. P5The Conference program's website is located at http://www.hkame.org.hk/hkmec13/Programme%20timetable.pd

Assessment of vibrations induced in factories by automated guided vehicles

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Evaluation of Local & Global Ductility Relationships for Low-Rise Masonry-Infilled Reinforced Concrete Frame Structures

The paper presents the findings on a parametric study of the period lengthening effects of low-rise masonryinfilled reinforced concrete frame buildings using an incremental dynamic analysis (IDA). Simplified 2D building models utilizing Bouc-Wen model for describing strength, stiffness degradation and pinching effect were subjected to some selected ground motion records ranging from far to near field earthquakes in low to high seismicity regions. Simple equations correlating local to global ductilities derived from pushover (PO) analysis for buildings under soft storey failure mechanism are proposed. The equations take into account the governing factors like critical interstorey drift and number of storeys. The applicability of the equations was verified up to 7-storey buildings from the results of IDA. Such simple ductility relationships are likely to facilitate mostly the coefficient-based method, in which the typical PO analysis may be bypassed and allows making intuitive insight into the seismic performance of buildings.published_or_final_versio

Survival of molar teeth after resective periodontal therapy - A retrospective study

AIM: To study outcomes of molar teeth after resective therapy performed with the intention to prolong the lifespan of teeth having one or more unsaveable roots, and without which tooth extraction would be inevitable. MATERIAL AND METHODS: Clinical records of 149 subjects who had undergone resective therapy were retrieved. Demography and dental history were recorded, and a recall examination was undertaken. Cox regression models were performed. RESULTS: Of the 149 resective therapies, 132 (88.6%) were performed for periodontal reasons. Eighty-nine (59.7%) teeth subjected to resective therapies had been extracted by the time of recall (mean 10 years post-resection). The median survival period was 74 months. Factors significantly associated with shorter survival duration of teeth subjected to resective therapy were: age at resective therapy; pre-operative radiographic bone height of the remaining root(s) <50%; pre-treatment mobility II or above and not being splinted to neighbouring teeth nor incorporated as a bridge abutment. CONCLUSION: There was increased risk of tooth loss with increasing age at resection, grade II mobility or above, and reduced pre-operative radiographic bone heights around roots to remain. Splinting of a resected tooth to neighbouring teeth appeared to confer a protective effect towards its survival.postprin

The prevalence of problem-drinking and other health-related behaviours in a sample of Hong Kong general hospital patients

Author name used in this publication: David ArthurAuthor name used in this publication: Leung Sau FongVersion of RecordPublishe

The prevalence of problem drinking and other health-related behaviours in a sample of Hong Kong general hospital patients

Objective: Little research evidence is available on the prevalence of problem drinking and other health related behaviours in Hong Kong. The purpose of this study was to test the utility, the validity and reliability of the AUDIT, a well-tested and validated screening instrument for alcohol consumption, in the Chinese language and with a sample of Hong Kong hospital patients. The study examined the prevalence of problem-drinkers amongst a sample of general hospital patients and compared this to the prevalence of other health-related behaviours. Method: The AUDIT was translated into Chinese and embedded in a broader lifestyle questionnaire and administered to a convenience sample of 121 general hospital patients in a busy Hong Kong general hospital. Results: 44% of the sample had received no formal education or were educated at the primary level and the respondents felt the people who should be interested in their health were relatives and friends ahead of doctors and nurses. The sample expressed they had a definite weight problem (28%); an eating problem (16%); a smoking problem (22%); a drinking problem (4%) and a fitness problem (23%). The AUDIT proved internally consistent and was able to detect that 44% of the respondents were non-drinkers and that 11 % were drinking at a hazardous or harmful level. Conclusions: The findings encouraged the future use of this Chinese version of the AUDIT in future research and provided useful baseline data for health related behaviours as well as suggesting that Hong Kong health care workers consider seriously their role in working with people and their families in relation to health promotion and education

Management and outcome of antenatally diagnosed congenital cystic adenomatoid malformation of the lung

Objective: To review the management and outcome of babies with antenatally diagnosed congenital cystic adenomatoid malformation. Design: Retrospective cohort review. Setting: Tertiary neonatal care unit at Queen Mary Hospital and antenatal diagnostic centre at Tsan Yuk Hospital. Patients: Consecutive patients with antenatally suspected congenital cystic adenomatoid malformation in their concepti among antenatal patients attending Tsan Yuk Hospital from 1994 to 2002. Twenty-four of 33 cases were referred to Queen Mary Hospital for postnatal management and for whom comprehensive records were available for analysis in 23. Interventions: Postnatal interventions in their babies included investigational imaging for congenital cystic adenomatoid malformation and surgery. Main outcome measures: Antenatal and postnatal outcome, as well as pathology of the excised lesions. Results: Antenatal outcome: termination of pregnancy in two cases and spontaneous abortion in one; in-utero regression was documented in nine cases and in one hydropic change was apparent. Postnatal outcome: only eight of 20 babies born alive had symptoms in neonatal period. Two developed serious infective complications in infancy, one with documented in-utero regression. Pulmonary parenchymal abnormalities were detected on computed tomography of the thorax in six of seven cases with normal or non-specific chest radiograph findings. Among nine cases with in-utero regression, congenital cystic adenomatoid malformation was confirmed by operative histology in five and abnormal computed tomography findings in three. Fifteen babies underwent surgical excision, one of whom died because of severe pre-existing pulmonary hypoplasia and nine endured minor postoperative complications. A favourable outcome was documented at a mean follow-up of 22 months (range, 2 months-7 years). Conclusions: In-utero regression of congenital cystic adenomatoid malformation on antenatal ultrasound may not represent genuine resolution. Computed tomographic thorax should be considered in all newborns with antenatally diagnosed congenital cystic adenomatoid malformation, and if confirmed early operation before first hospital discharge is recommended.published_or_final_versio

Failure of phylogeny inferred from multilocus sequence typing to represent bacterial phylogeny

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Experimental studies of the material properties of the forewing of cicada (Homóptera, Cicàdidae)

Detailed investigations on the structural and mechanical properties of the forewing of the cicada were carried out. Measurement of the structures of the wings showed that the thickness of the membrane of each cell and the diameter of each vein were non-uniform in both the longitudinal and transverse directions, and their means were approximately 12.2 and 133.3 μm, respectively. However, the aspect ratios of the wings and the bodies were quite uniform and were approximately equal to 2.98 and 2.13, respectively. Based on the measured thickness, mass and area of the membranes of the cells, the mean density and the mean area density of the wing were approximately 2.3 g cm -3 and 2.8×10 -3 g cm -2, respectively. In addition, the diameters of the veins of the wings, including the diameters of the holes in the vein of the leading edge, were examined. The mechanical properties of the wing were investigated separately by nanoindentation and tensile testing. The results indicated that the mean Young's modulus, hardness and yield stress of the membranes of the wings were approximately 3.7 GPa, 0.2 GPa and 29 MPa, respectively, and the mean Young's modulus and strength of the veins along the direction of the venation of wings were approximately 1.9 GPa and 52 MPa, respectively. Finally, the relevant results were briefly analyzed and discussed, providing a guideline to the biomimetic design of the aerofoil materials of micro air vehicles.published_or_final_versio

Association between beta-blocker use and obesity in Hong Kong Chinese elders: a post-hoc analysis.

INTRODUCTION:Studies of Caucasian populations have shown that beta-blockers may exacerbate weight gain, a risk factor for many chronic diseases. Still, beta-blockers are the most prescribed antihypertensives in the Chinese population in Hong Kong. We aimed to explore the association between beta-blocker use, hypertension, and weight status of this population. METHODS:A post-hoc analysis regarding body mass index (BMI) and the use of beta-blockers was performed based on the medication profile of community-dwelling older adults. Participants' BMI, hypertension diagnosis, name, dose, frequency, route of administration of beta-blockers, and other drugs that may alter body weight were recorded. RESULTS:Of 1053 Chinese individuals aged ≥65 years (mean age 76.9±7.2 years, 80% female) from 32 elderly centres in Hong Kong, 18% (185/1053) of them consumed beta-blockers. That group also had a significantly larger proportion of obese individuals (45.9% vs 32.1%, P=0.002). After adjusting for other weight-altering drugs, beta-blockers remained a significant predictor of overweight and obesity (P=0.001). As the hypertensive population had significantly higher BMI than the normotensive population (24.3±3.6 vs 22.9±3.5, P<0.001), a sub-analysis on those with hypertension diagnosis confirmed that only the hypertensive population taking atenolol had a significantly larger population of obese individuals (BMI ≥25) compared with those who took metoprolol (58.9% vs 38.5%, P=0.03) and those who did not take any beta-blockers (58.9% vs 38.4%, P=0.007). CONCLUSIONS:Our findings taken together with other guideline reservations cast doubt on whether beta-blockers, particularly atenolol, should be the major drug prescribed to older adults with hypertension