Chemical composition and toxic activity of essential oil of Caryopteris incana against Sitophilus zeamais

During our screening program for new agrochemicals from Chinese medicinal herbs, essential oil of Caryopteris incana aerial parts was found to possess strong insecticidal activities against the maize weevil, Sitophilus zeamais. A total of 37 components of the essential oil were identified by GC and GC/MS. Estragole (24.8%) and linalool (14.0%) are the two main components of the essential oil followed by 1,8-cineol (5.2%) and δ-guaiene (4.1%). The essential oil possesses strong fumigant toxicity against S. zeamais adults with an LC50 value of 10.05 mg/L air. The essential oil of C. incana also showed contact toxicity against S. zeamais adults with an LD50 value of 122.65 μg/adult. The essential oil C. incana may have potential to be developed as a new natural fumigant/insecticide for the control of stored product insects.Key words: Caryopteris incana, Sitophilus zeamais, fumigant, contact toxicity, essential oil composition, estragole, linalool

Pilot project of integration of Chinese medicine (acupuncture) and Western medicine for neurohabilitation of children with acquired brain injury: a study of 2 cases

PURPOSE: To demonstrate if there is any efficacy of integration of Chinese medicine (acupuncture) and western medicine for rehabilitation for two children with acquired brain injury (ABI). METHODS: Two children (M/1 year, with dystonic cerebral palsy, cortical visual impairment and global developmental delay due to acute encephalitis; and M/12 years, with spastic tetraplegia, cortical visual impairment, and severe mental retardation due to hypoxic-ischaemic encephalopathy related to hypertrophic cardiomyopathy) were enrolled into our pilot programme which had started as the ‘First Integrated Chinese Medicine and Western Medicine for Neurorehabilitation of Children with Traumatic or Acquired Brain Injury under the Hospital Authority’ in June 2008. Both of them received daily acupuncture treatment and conventional neurohabilitation programme for 4 months. Pre- and post-assessment were performed for both cases. Deoxyglucose PET scan of the brain, parental daily reports for any change after each acupuncture session were monitored. Objective outcome measures were performed by the Neurohabilitation Team with allied health disciplines including physiotherapist, occupational therapist, optometrist, audiologist, speech therapist and clinical psychologist in pre- and post-acupuncture treatment using objective outcome measures including Modified Ashworth Spasticity Scale, CVI assessment, Video Fluoroscopic Swallow Study (VFSS) and Functional Independence Measure of Children (WeeFIM). Videos were taken by blind assessors. RESULTS: PET scan of the brain showed mild-to-moderate increase in glucose uptake for both cases. Videos and clinical outcome measures showed improvement in vision and other parameters. CONCLUSIONS: A short and intensive course of acupuncture can be effective in improving visual and functional outcome for children with ABI. Further research is underway to assess the practicability of organising this model of integration of Chinese medicine (acupuncture) and western medicine for neurohabilitation of children with ABI in Hong Kong.published_or_final_versio

Dental caries status and its associated factors among 5-year-old Hong Kong children: A cross-sectional study

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Human coronavirus NL63 infection and other coronavirus infections in children hospitalized with acute respiratory disease in Hong Kong, China

Background. Human coronavirus NL63 (HCoV-NL63) is a recently discovered human coronavirus found to cause respiratory illness in children and adults that is distinct from the severe acute respiratory syndrome (SARS) coronavirus and human coronaviruses 229E (HCoV-229E) and OC43 (HCoV-OC43). Methods. We investigated the role that HCoV-NL63, HCoV-OC43, and HCoV-229E played in children hospitalized with fever and acute respiratory symptoms in Hong Kong during the period from August 2001 through August 2002. Results. Coronavirus infections were detected in 26 (4.4%) of 587 children studied; 15 (2.6%) were positive for HCoV-NL63, 9 (1.5%) were positive for HCoV-OC43, and 2 (0.3%) were positive for HCoV-229E. In addition to causing upper respiratory disease, we found that HCoV-NL63 can present as croup, asthma exacerbation, febrile seizures, and high fever. The mean age (± standard deviation [SD]) of the infected children was 30.7 ± 19.8 months (range, 6-57 months). The mean maximum temperature (± SD) for the 12 children who were febrile was 39.3°C ± 0.9°C, and the mean total duration of fever (± SD) for all children was 2.6 ± 1.2 days (range, 1-5 days). HCoV-NL63 infections were noted in the spring and summer months of 2002, whereas HCoV-OC43 infection mainly occurred in the fall and winter months of 2001. HCoV-NL63 viruses appeared to cluster into 2 evolutionary lineages, and viruses from both lineages cocirculated in the same season. Conclusions. HCoV-NL63 is a significant pathogen that contributes to the hospitalization of children, and it was estimated to have caused 224 hospital admissions per 100,000 population aged 6 years each year in Hong Kong. © 2005 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio

A No-Go Theorem for M5-brane Theory

The BLG model for multiple M2-branes motivates an M5-brane theory with a novel gauge symmetry defined by the Nambu-Poisson structure. This Nambu-Poisson gauge symmetry for an M5-brane in large C-field background can be matched, on double dimension reduction, with the Poisson limit of the noncommutative gauge symmetry for a D4-brane in B-field background. Naively, one expects that there should exist a certain deformation of the Nambu-Poisson structure to match with the full noncommutative gauge symmetry including higher order terms. However, We prove the no-go theorem that there is no way to deform the Nambu-Poisson gauge symmetry, even without assuming the existence of a deformation of Nambu-Poisson bracket, to match with the noncommutative gauge symmetry in 4+1 dimensions to all order, regardless of how the double dimension reduction is implemented.Comment: v4: minor modifications

Microwave enhanced ion-cut silicon layer transfer

Microwave heating has been used to decrease the time required for exfoliation of thin single-crystalline silicon layers onto insulator substrates using ion-cut processing. Samples exfoliated in a 2.45 GHz, 1300 W cavity applicator microwave system saw a decrease in incubation times as compared to conventional anneal processes. Rutherford backscattering spectrometry, cross sectional scanning electron microscopy, cross sectional transmission electron microscopy, and selective aperture electron diffraction were used to determine the transferred layer thickness and crystalline quality. The surface quality was determined by atomic force microscopy. Hall measurements were used to determine electrical properties as a function of radiation repair anneal times. Results of physical and electrical characterizations demonstrate that the end products of microwave enhanced ion-cut processing do not appreciably differ from those using more traditional means of exfoliation. © 2007 American Institute of Physics

The Subleading Term of the Strong Coupling Expansion of the Heavy-Quark Potential in a N=4\mathcal N=4 Super Yang-Mills Plasma

Applying the AdS/CFT correspondence, the expansion of the heavy-quark potential of the ${\cal N}$ supersymmetric Yang-Mills theory at large $N_c$ is carried out to the sub-leading term in the large 't Hooft coupling at nonzero temperatures. The strong coupling corresponds to the semi-classical expansion of the string-sigma model, the gravity dual of the Wilson loop operator, with the sub-leading term expressed in terms of functional determinants of fluctuations. The contributions of these determinants are evaluated numerically.Comment: 17 pages in JHEP3, typos fixed, updated version to be published in JHE

Hospital Authority audit of the outcome of endoscopic resection of superficial upper gastro-intestinal lesions in Hong Kong

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Plasma hydrogenation of strained Si/SiGe/Si heterostructure for layer transfer without ion implantation

We have developed an innovative approach without the use of ion implantation to transfer a high-quality thin Si layer for the fabrication of silicon-on-insulator wafers. The technique uses a buried strained SiGe layer, a few nanometers in thickness, to provide H trapping centers. In conjunction with H plasma hydrogenation, lift-off of the top Si layer can be realized with cleavage occurring at the depth of the strained SiGe layer. This technique avoids irradiation damage within the top Si layer that typically results from ion implantation used to create H trapping regions in the conventional ion-cut method. We explain the strain-facilitated layer transfer as being due to preferential vacancy aggregation within the strained layer and subsequent trapping of hydrogen, which lead to cracking in a well controlled manner. © 2005 American Institute of Physics