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1.
Microbiol Resour Announc ; 13(4): e0110623, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38470266

RESUMEN

The endophytic strain Gluconobacter frateurii ML.ISBL3 was isolated from aerial roots of Syngonium podophyllum in Hong Kong. Its complete genome, established through hybrid assembly, comprises a single chromosome of 3,309,710 bp (56.30% G+C).

2.
Microbiol Resour Announc ; 13(4): e0116323, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38509053

RESUMEN

The endophytic strain Klebsiella variicola subsp. variicola ML.9ba2 was isolated from aerial roots of Philodendron erubescens in Hong Kong. Its complete genome of 5,682,083 bp (57.29% G+C), comprising a single chromosome and an IncF plasmid, was established through hybrid assembly.

3.
Microbiol Resour Announc ; 12(10): e0046923, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37772874

RESUMEN

Kosakonia pseudosacchari RX.G5M8, a putative methylotroph, was isolated from garden soil in Hong Kong. Its complete genome, a single chromosome of 4,953,935 bp (GC content 53.91%), was established through hybrid assembly.

4.
Anaesthesia ; 78(9): 1112-1119, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37381615

RESUMEN

The amount of aerosol generation associated with the use of positive pressure ventilation via a supraglottic airway device has not been quantified. We conducted a two-group, two-centre, prospective cohort study in which we recruited 21 low-risk adult patients scheduled for elective surgery under general anaesthesia with second-generation supraglottic airway devices. An optical particle sizer and an isokinetic sampling probe were used to record particle concentrations per second at different size distributions (0.3-10 µm) during use as well as baseline levels during two common activities (conversation and coughing). There was a median (IQR [range]) peak increase of 2.8 (1.5-4.5 [1-28.1]) and 4.1 (2.0-7.1 [1-18.2]) times background concentrations during SAD insertion and removal. Most of the particles generated during supraglottic airway insertion (85.0%) and removal (85.3%) were < 3 µm diameter. Median (IQR [range]) aerosol concentration generated by insertion (1.1 (0.6-5.1 [0.2-22.3]) particles.cm-3 ) and removal (2.1 (0.5-3.0 [0.1-18.9]) particles.cm-3 ) of SADs were significantly lower than those produced during continuous talking (44.5 (28.3-70.5 [2.0-134.5]) particles.cm-3 ) and coughing (141.0 (98.3-202.8 [4.0-296.5]) particles.cm-3 ) (p < 0.001). The aerosol levels produced were similar with the two devices. The proportion of easily inhaled and small particles (<1 µm) produced during insertion (57.5%) and removal (57.5%) was much lower than during talking (99.1%) and coughing (99.6%). These results suggest that the use of supraglottic airway devices in low-risk patients, even with positive pressure ventilation, generates fewer aerosols than speaking and coughing in awake patients.


Asunto(s)
Intubación Intratraqueal , Aerosoles y Gotitas Respiratorias , Adulto , Humanos , Intubación Intratraqueal/métodos , Estudios Prospectivos , Respiración con Presión Positiva , Ventilación con Presión Positiva Intermitente , Tos/etiología
5.
Microbiol Resour Announc ; 12(4): e0001523, 2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-36920231

RESUMEN

The C1-metabolizing strain Enterobacter roggenkampii RX.G5M56 was isolated from a freshwater stream in Hong Kong. Its complete genome, a single chromosome of 4,772,201 bp (GC content of 56.05%), was established through hybrid assembly.

6.
Anaesthesia ; 77 Suppl 1: 123-133, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35001381

RESUMEN

Patients with Parkinson's disease are at higher risk of peri-operative medical and surgical complications. Multidisciplinary management, early recognition of potential complications, specialised care of medications and intra-operative protection of the vulnerable brain are all important aspects of the peri-operative management of patients with Parkinson's disease. Advances in continuous dopaminergic treatment, development of a peri-operative Parkinson's disease pathway and application of telemedicine are starting to play a role in improving peri-operative care. Management of patients with advanced Parkinson's disease is also evolving, with potential for incorporation of integrated care and changes in the anaesthetic management for deep brain stimulation surgery. There are new methods for localisation of target nuclei and increasing insight on the effects of anaesthetic drugs on microelectrode recordings and clinical outcomes. Parkinson's disease is a progressive disease, but management is improving with better peri-operative care for patients.


Asunto(s)
Anestesia/métodos , Manejo de la Enfermedad , Monitoreo Intraoperatorio/métodos , Enfermedad de Parkinson/terapia , Atención Perioperativa/métodos , Anestesia/efectos adversos , Anestesia/normas , Dopaminérgicos/uso terapéutico , Humanos , Monitoreo Intraoperatorio/normas , Enfermedad de Parkinson/diagnóstico
7.
Mar Pollut Bull ; 155: 111129, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32469765

RESUMEN

Ten global harbours were assessed for sediment quality by quantifying the magnitude of anthropogenic change and ecological risk. Anthropogenic change (enrichment) was high for Derwent River and Sydney estuary, moderate for Santander Harbour, Rio de Janeiro and Dublin Port, slight for Hong Kong, minimal for Darwin. All 10 enrichment indices used showed similar results. Derwent River sediment was rated at high ecological risk, followed by Sydney and Santander estuaries with moderate risk. Auckland and Darwin sediments exhibited minimal ecological risk and sediment in the remaining harbours (Dublin, Hong Kong, Ravenna, Ria de Vigo and Rio de Janeiro) were assessed at slight ecological risk. The extraordinary variety of environments and types/quantities/qualities of data investigated resulted in as much a critique and development of methodology, as an assessment of human impact, including unique techniques for elemental normalisation and contaminant classification. Recommendations for an improved technical framework for sediment quality assessment are provided.


Asunto(s)
Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Hong Kong , Humanos , Medición de Riesgo , Ríos
8.
Mar Pollut Bull ; 124(2): 573-586, 2017 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-28314615

RESUMEN

Marine ecosystems are subject to anthropogenic change at global, regional and local scales. Global drivers interact with regional- and local-scale impacts of both a chronic and acute nature. Natural fluctuations and those driven by climate change need to be understood to diagnose local- and regional-scale impacts, and to inform assessments of recovery. Three case studies are used to illustrate the need for long-term studies: (i) separation of the influence of fishing pressure from climate change on bottom fish in the English Channel; (ii) recovery of rocky shore assemblages from the Torrey Canyon oil spill in the southwest of England; (iii) interaction of climate change and chronic Tributyltin pollution affecting recovery of rocky shore populations following the Torrey Canyon oil spill. We emphasize that "baselines" or "reference states" are better viewed as envelopes that are dependent on the time window of observation. Recommendations are made for adaptive management in a rapidly changing world.


Asunto(s)
Cambio Climático , Explotaciones Pesqueras , Contaminación por Petróleo , Contaminación del Agua , Animales , Ecosistema , Ecotoxicología/métodos , Inglaterra , Ambiente , Peces , Biología Marina/métodos , Compuestos de Trialquiltina/toxicidad , Contaminantes Químicos del Agua/toxicidad
9.
Curr Gerontol Geriatr Res ; 2017: 6215917, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28348584

RESUMEN

Age-friendliness, promoted by the World Health Organization (WHO), aims to enable and support individuals in different aspects of life for fostering life satisfaction and personal well-being as they age. We identified specific aspect(s) of age-friendliness associated with life satisfaction and examined similarities and differences in age-friendliness and life satisfaction in young-old and old-old adults. Six hundred and eighty-two ageing adults were asked to complete a survey questionnaire consisting of the Age-friendly City Scale, Satisfaction with Life Scale, and sociodemographic variables. Multiple linear regression analysis was used to examine the effects of various domains of age-friendliness on life satisfaction among the young-old adults (aged 65 to 74, n = 351) and the old-old adults (aged 75 to 97, n = 331). Common domains associated with life satisfaction in both young-old and old-old groups were transportation and social participation. Community and health services were associated with life satisfaction for the young-old group only. On the other hand, civic participation and employment was significantly associated with the old-old group only. Social participation is important for the young-old and the old-old. Ageing older adults can be a resource to the society. Implications for promoting and implementing age-friendliness were discussed in the context of successful and productive ageing and the need for a more refined taxonomy of social activities.

10.
J Chem Inf Model ; 54(9): 2515-23, 2014 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-25133742

RESUMEN

Reliable computer models for the prediction of chemical biodegradability from molecular descriptors and fingerprints are very important for making health and environmental decisions. Coupling of the differential evolution (DE) algorithm with the support vector classifier (SVC) in order to optimize the main parameters of the classifier resulted in an improved classifier called the DE-SVC, which is introduced in this paper for use in chemical biodegradability studies. The DE-SVC was applied to predict the biodegradation of chemicals on the basis of extensive sample data sets and known structural features of molecules. Our optimization experiments showed that DE can efficiently find the proper parameters of the SVC. The resulting classifier possesses strong robustness and reliability compared with grid search, genetic algorithm, and particle swarm optimization methods. The classification experiments conducted here showed that the DE-SVC exhibits better classification performance than models previously used for such studies. It is a more effective and efficient prediction model for chemical biodegradability.


Asunto(s)
Evolución Química , Máquina de Vectores de Soporte , Algoritmos
11.
Epidemiol Infect ; 142(5): 994-1001, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23930640

RESUMEN

Varicella is a common and highly contagious childhood disease which impacts the public worldwide. Hong Kong children can only be vaccinated against the disease in private practice. The varicella vaccination rate of local children in preschool is uncertain. Therefore a cross-sectional kindergarten-based parent-administered questionnaire survey was conducted in Hong Kong during 2012. Twelve kindergartens were randomly selected from a complete school list from the Education Bureau of Hong Kong. In total, 1285/1538 (83·6%) parents consented to join the study and completed the questionnaires. The overall varicella infection rate was 19·5% and the uptake of varicella vaccination rate was 57·6%. Barriers against varicella vaccination were mostly due to parental uncertainties about the effectiveness of vaccine, lack of recommendations from doctors or government, and adverse side-effects of the vaccine. The government and healthcare professional bodies are strongly recommended to further enhance health education among healthcare professionals, encouraging their active promotion of varicella vaccination for their patients. Furthermore, health education through various stakeholders is crucial to enhance parental awareness of varicella, as well as the effectiveness and safety of varicella vaccine.


Asunto(s)
Vacuna contra la Varicela/administración & dosificación , Varicela/epidemiología , Vacunación/estadística & datos numéricos , Varicela/prevención & control , Niño , Preescolar , Estudios Transversales , Medicina Familiar y Comunitaria , Femenino , Hong Kong/epidemiología , Humanos , Masculino , Encuestas y Cuestionarios
12.
Hong Kong Med J ; 19(3): 203-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23650200

RESUMEN

OBJECTIVE. To investigate the prevalence of pre-cancerous uterine cervix lesions as detected in Papanicolaou (Pap) smears from female sex workers in Hong Kong. DESIGN. Retrospective analysis of laboratory records. SETTING. Private anatomical pathology laboratory, Hong Kong. PATIENTS. Female sex workers undergoing Pap smear examinations at two non-governmental organisations between 2006 and 2012. MAIN OUTCOME MEASURES. Detection of pre-cancerous uterine cervical conditions and their management. RESULTS. A total of 2697 satisfactory Pap smears from female sex workers were performed during the study period from 2006 to 2012. In these subjects, the point prevalence of low-grade squamous intraepithelial lesion and atypical squamous cells of unknown significance was 10.12% (compared with 3.92% for the general population during the same period), whereas that of high-grade squamous intraepithelial lesions and atypical squamous cells of unknown significance with or without high-grade intraepithelial lesions was 2.22% (compared with 0.54% in the general population). For both categories of lesions, the higher prevalence among female sex workers than in the general population was statistically significant. Most patients who had abnormal Pap smears received proper referrals and follow-up management according to recommended guidelines. CONCLUSIONS. Female sex workers in Hong Kong as a group had a significantly higher prevalence of abnormal Pap smears than the general population. Non-governmental organisations providing free-of-charge screening services to these women helped early detection and proper follow-up for those who had abnormal Pap smears, whilst also increasing their awareness of women's health issues.


Asunto(s)
Lesiones Precancerosas/epidemiología , Trabajadores Sexuales/estadística & datos numéricos , Displasia del Cuello del Útero/epidemiología , Frotis Vaginal/estadística & datos numéricos , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Hong Kong/epidemiología , Humanos , Tamizaje Masivo/métodos , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Lesiones Precancerosas/diagnóstico , Derivación y Consulta , Estudios Retrospectivos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Adulto Joven , Displasia del Cuello del Útero/diagnóstico
13.
Hong Kong Med J ; 19(1): 69-73, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23378358

RESUMEN

As a means of preventing secondary ischaemic stroke, angioplasty and stenting are considered potentially beneficial for patients with severe intracranial atherosclerotic stenosis. However, the role of stenting has been challenged since the publication of the first randomised controlled trial on Stenting versus Aggressive Medical Management for Preventing Recurrent stroke in Intracranial arterial Stenosis (SAMMPRIS). This indicated that aggressive medical management was superior to stenting using Wingspan to prevent recurrent stroke, because stenting has a high peri-procedural stroke and death rate. In this paper, we review the management of intracranial atherosclerosis, revisit the skepticism on stenting, and state our position on the topic in the form of recommendations. These are based on the prevalence of the disease in Hong Kong, the high risk of recurrent stroke despite medical therapy in the presence of haemodynamic intracranial stenosis without sufficient collaterals, an analysis of the weak points of SAMMPRIS, and results of clinical studies in Hong Kong.


Asunto(s)
Angioplastia/métodos , Arteriosclerosis Intracraneal/cirugía , Stents , Accidente Cerebrovascular/prevención & control , Isquemia Encefálica/etiología , Isquemia Encefálica/prevención & control , Constricción Patológica , Hong Kong , Humanos , Arteriosclerosis Intracraneal/complicaciones , Arteriosclerosis Intracraneal/patología , Prevención Secundaria , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/etiología
14.
Hong Kong Med J ; 15(6): 482-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19966356

RESUMEN

Thromboembolic events are known complications of endovascular coiling of intracerebral aneurysms. We report a case of a 50-year-old patient whose ruptured middle cerebral artery aneurysm was treated with endovascular coiling, which was complicated by occlusion of the inferior M2 trunk during the procedure. An emergency craniotomy was performed to enable coil retrieval, evacuation of the thrombus and clipping of the aneurysm. All the middle cerebral artery branches were recanalised and the patient recovered with no neurological deficits. Our experience suggests that an emergency salvage operation for thrombosis after endovascular coiling is a treatment option offering a good clinical outcome.


Asunto(s)
Aneurisma Roto/terapia , Craneotomía , Embolización Terapéutica/efectos adversos , Terapia Recuperativa , Tromboembolia/etiología , Tromboembolia/cirugía , Angiografía Cerebral , Embolización Terapéutica/instrumentación , Femenino , Humanos , Aneurisma Intracraneal/terapia , Persona de Mediana Edad , Instrumentos Quirúrgicos
15.
Age Ageing ; 38(6): 724-30, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19767629

RESUMEN

BACKGROUND: falls are the leading causes of accidental death and fragility fractures in older adults. Interventions that assess and reduce falls risk are underutilised. OBJECTIVE: to evaluate the impact of a multifaceted community-based programme aimed at optimising evidence-based management of patients at risk for fall-related fractures. DESIGN: this was a randomised trial performed from 2003 to 2006. SETTING: community-based intervention in Ontario, Canada. PARTICIPANTS: eligible patients were community-dwelling, aged > or =55 years and identified to be at risk for fall-related fractures. A total of 201 patients were allocated to the intervention group or to usual care. INTERVENTION: components of the intervention included assessment of falls risk, functional status and home environment, and patient education. MEASUREMENTS: primary outcome was the implementation of appropriate falls risk assessment at 6 months. Secondary outcomes included falls and fractures at 6 and 12 months. RESULTS: the mean age of participants was 72 years, and 41% had fallen with injury in the previous year. Compared to usual care, the intervention increased the number of referrals made to physiotherapy [21% (21/101) vs 6.0% (6/100); relative risk (RR) 3.47, 95% confidence interval (CI) 1.46-8.22] and occupational therapy [15% (15/101) vs 0%; RR 30.7, 95% CI 1.86 to >500]. At 12 months, the number of falls in the intervention group was greater than in the usual care group [23% (23/101) vs 11% (11/100); RR 2.07, 95% CI 1.07-4.02]. CONCLUSIONS: compared to usual care, a multi-faceted intervention increased referrals to physiotherapy and occupational therapy but did not reduce risk of falls. Similar falls reduction interventions cannot be recommended based on the results of this study.


Asunto(s)
Accidentes por Caídas/prevención & control , Actividades Cotidianas , Gestión de Riesgos/organización & administración , Anciano , Anciano de 80 o más Años , Medicina Basada en la Evidencia , Femenino , Evaluación Geriátrica , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ontario , Evaluación de Resultado en la Atención de Salud , Educación del Paciente como Asunto , Factores de Riesgo
16.
Trials ; 9: 62, 2008 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-18983670

RESUMEN

BACKGROUND: Osteoporosis-related fractures are a significant public health concern. Interventions that increase detection and treatment of osteoporosis, as well as prevention of fractures and falls, are substantially underutilized. This paper outlines the protocol for a pragmatic randomised trial of a multifaceted community-based care program aimed at optimizing the evidence-based management of falls and fractures in patients at risk. DESIGN: 6-month randomised controlled study. METHODS: This population-based study was completed in the Algoma District of Ontario, Canada a geographically vast area with Sault Ste Marie (population 78,000) as its main city. Eligible patients were allocated to an immediate intervention protocol (IP) group, or a delayed intervention protocol (DP) group. The DP group received usual care for 6 months and then was crossed over to receive the interventions. Components of the intervention were directed at the physicians and their patients and included patient-specific recommendations for osteoporosis therapy as outlined by the clinical practice guidelines developed by Osteoporosis Canada, and falls risk assessment and treatment. Two primary outcomes were measured including implementation of appropriate osteoporosis and falls risk management. Secondary outcomes included quality of life and the number of falls, fractures, and hospital admissions over a twelve-month period. The patient is the unit of allocation and analysis. Analyses will be performed on an intention to treat basis. DISCUSSION: This paper outlines the protocol for a pragmatic randomised trial of a multi-faceted, community-based intervention to optimize the implementation of evidence based management for patients at risk for falls and osteoporosis. TRIAL REGISTRATION: This trial has been registered with clinicaltrials.gov (ID: NCT00465387).

17.
Intervirology ; 51(3): 173-81, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18724064

RESUMEN

The outbreak of severe acute respiratory syndrome (SARS), caused by a distinct coronavirus, in 2003 greatly threatened public health in China, Southeast Asia as well as North America. Over 1,000 patients died of the SARS virus, representing 10% of infected people. Like other coronaviruses, the SARS virus also utilizes a surface glycoprotein, namely the spike protein, to infect host cells. The spike protein of SARS virus consists of 1,255 amino acid residues and can be divided into two sub-domains, S1 and S2. The S1 domain mediates the binding of the virus to its receptor angiotensin-converting enzyme 2, which is abundantly distributed on the surface of human lung cells. The S2 domain mediates membrane fusion between the virus and the host cell. Hence two strategies can be used to block the infection of the SARS virus, either by interfering with the binding of the S1 domain to the receptor or by blocking the fusion of the virus with the cell membrane mediated by the S2 domain. Several antibodies against the S1 domain have been generated and all of them are able to neutralize the virus in vitro and in vivo using animal models. Unfortunately, point mutations have been identified in the S1 domain, so that the virus isolated in the future may not be recognized by these antibodies. As no mutation has been found in the S2 domain indicating that this region is more conserved than the S1 domain, it may be a better target for antibody binding. After predicting the immunogenicity of the epitopes of the S2 domain, we chemically synthesized two peptides and also expressed one of them using a recombinant DNA method. We screened a phage displaying library of human single-chain antibodies (ScFv) against the predicted epitopes and obtained a human ScFv which can recognize the SARS virus in vitro.


Asunto(s)
Anticuerpos Antivirales/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/genética , Asia Sudoriental , China , Epítopos/inmunología , Humanos , Datos de Secuencia Molecular , Mutación , Pruebas de Neutralización , América del Norte , Biblioteca de Péptidos , Unión Proteica , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética
18.
Hong Kong Med J ; 14(4): 292-5, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18685162

RESUMEN

OBJECTIVE: To examine the cellular characteristics and other possible factors affecting the correct prediction of ThinPrep cervical smears from patients with high-grade squamous intraepithelial lesions. DESIGN: Retrospective study. SETTING: Private anatomical pathology service, Hong Kong. PATIENTS: Patients (n=98) with biopsy-confirmed high-grade squamous intraepithelial lesion of the uterine cervix encountered between 2004 and 2006. MAIN OUTCOME MEASURES: Correct prediction of the cervical ThinPrep Papanicolaou tests. RESULTS: There were no significant differences in age, hormonal status, degree of inflammation, and the presence or absence of endocervical/metaplastic cells between the true-positive and false-negative groups. There was a significant difference in the number of abnormal cells present and the screening time between the two groups. Approximately 79% (34/43) false-negative smears had 100 or less abnormal cells, while only 11% (5/45) true-positive smears had 100 or less abnormal cells (P<0.001). The true-positive smears were also more likely to contain koilocytic cells and abnormal cells with hyperchromatic nuclei. CONCLUSIONS: The number of abnormal cells present, the presence or absence of koilocytic cells, and the presence or absence of abnormal cells with nuclear hyperchromasia appeared to be independent factors affecting the correct prediction of smears from patients with high-grade squamous intraepithelial lesions.


Asunto(s)
Carcinoma de Células Escamosas/patología , Prueba de Papanicolaou , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Frotis Vaginal/métodos , Adulto , Factores de Edad , Biopsia con Aguja , Carcinoma de Células Escamosas/epidemiología , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Hong Kong , Humanos , Inmunohistoquímica , Incidencia , Tamizaje Masivo/normas , Tamizaje Masivo/tendencias , Valor Predictivo de las Pruebas , Probabilidad , Medición de Riesgo , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/epidemiología , Displasia del Cuello del Útero/epidemiología
19.
Nanotechnology ; 19(18): 185301, 2008 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21825687

RESUMEN

Enhanced light extraction from a GaN-based power chip (PC) of green light-emitting diodes (LEDs) with a rough p-GaN surface using nanoimprint lithography is presented. At a driving current of 350 mA and with a chip size of 1 mm × 1 mm packaged on transistor outline (TO)-cans, the light output power of the green PC LEDs with nano-rough p-GaN surface is enhanced by 48% when compared with the same device without a rough p-GaN surface. In addition, by examining the radiation patterns, the green PC LED with nano-rough p-GaN surface shows stronger light extraction with a wider view angle. These results offer promising potential to enhance the light output powers of commercial light-emitting devices by using the technique of nanoimprint lithography under suitable nanopattern design.

20.
Chemosphere ; 69(1): 135-44, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17509645

RESUMEN

Experiments were performed to determine the acute and chronic toxicities of tributyltin (TBT) (nominal concentrations) to polychaete Hydroides elegans. Firstly, static tests were performed to examine the lethal effect of TBT on five life stages of H. elegans. The 48-h LC(50) (95% CI) for the eggs, 2-cells, trochophores, juveniles and adults was 0.18 (0.15-0.20), 0.97 (0.77-1.23), 2.36 (2.11-2.65), 2.86 (2.63-3.12) and 4.36 (4.04-4.71) microg TBT l(-1), respectively. Secondly, a 17-d static renewal chronic test was conducted to study sensitivity of the early development (egg to juvenile) to TBT. The survivorship, percent settlement and time to reach settlement were significantly reduced at 0.01 microg TBT l(-1). Effects of TBT on the juvenile growth and maturation were also studied through a 44-d chronic test. Lower survivorship and reduced tube growth were observed only at >or= 1 microg TBT l(-1), however, only H. elegans exposed to or= 0.1 microg TBT l(-1). Our results indicate that the early development of H. elegans is highly sensitive to TBT and this polychaete can be routinely employed as a test organism for both acute and chronic ecotoxicity bioassays in tropical and subtropical regions such as southern China.


Asunto(s)
Poliquetos/efectos de los fármacos , Compuestos de Trialquiltina/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Femenino , Dosificación Letal Mediana , Masculino , Poliquetos/fisiología , Reproducción/efectos de los fármacos , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica , Cigoto/efectos de los fármacos , Cigoto/fisiología
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