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1.
Hong Kong Med J ; 28(3): 275-276, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35765740
2.
Opt Express ; 29(5): 6824-6833, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726194

RESUMO

We have fabricated a Si racetrack optical modulator based on a III-V/Si hybrid metal-oxide-semiconductor (MOS) capacitor. The III-V/Si hybrid MOS optical phase shifter was integrated to a Si racetrack resonator with a coupling length of 200 µm and a coupling gap of 700 nm. The fabricated Si racetrack resonator demonstrated a small VπL of 0.059 Vcm. For 10-dB optical intensity modulation, the Si racetrack resonator showed a 60% smaller driving voltage than a Mach-Zehnder interferometer modulator with the same phase shifter, leading to a better balance between high energy efficiency and large modulation bandwidth.

3.
Opt Express ; 26(26): 35003-35012, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650915

RESUMO

We have demonstrated an ultra-power-efficient 2 × 2 Si Mach-Zehnder interferometer optical switch with III-V/Si hybrid metal-oxide-semiconductor (MOS) phase shifters. The efficient low-loss phase modulation enables low-crosstalk and broadband switching in conjunction with multimode interference couplers consisting of tapered input and output ports. Owing to the negligible gate leakage current in the hybrid MOS capacitor, the power consumption required for switching is 0.18 nW, approximately 107 times smaller than that of a Si thermo-optic phase shifter. We also demonstrated a switching time of less than 20 ns. The III-V/Si hybrid MOS phase shifter is promising for fabricating large-scale Si photonic integrated circuits that require efficient, low-loss, and high-speed optical phase control.

4.
Public Health ; 153: 70-77, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28957713

RESUMO

OBJECTIVE: This study was designed to investigate blood pressure (BP) profiles among Taiwanese women with different dietary patterns. STUDY DESIGN: Cross-sectional study. METHODS: A total of 269 non-hypertensive Taiwanese women, 40 years of age or older, were surveyed using structured questionnaires, and measurements of BP and physiological parameters were made. To assess differences among vegans, ovo-vegetarians, and meat eaters in terms of BP, demographic, and health behavior data, the chi-squared and Fisher's exact tests were employed for categorical variables, and analysis of variance and independent t-tests were performed for continuous variables. Multiple regression analysis was used to examine the relationship between BP and dietary patterns while controlling for potential confounding factors. RESULTS: A significant difference was found among the three test groups in terms of age, education, employment, stress, and waist-hip ratio. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) significantly differed among the three groups. After controlling for age, body weight, waist circumference, and hip circumference, the three groups were observed to be a significant risk factor of the SBP and DBP. The SBP and DBP of the ovo-vegetarian group were significantly lower than those of the meat-eater group. No significant differences were found between the vegan and meat-eater groups in terms of SBP and DBP. CONCLUSION: Dietary pattern is a likely risk factor for SBP and DBP outcomes in Taiwanese women. In particular, the SBP and DBP of ovo-vegetarians are the lowest among the values observed for all dietary patterns. This finding suggests that an ovo-vegetarian diet is beneficial for long-term BP control and prevention of hypertension in females.


Assuntos
Pressão Sanguínea , Dieta Vegetariana , Dieta/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Ovos , Feminino , Humanos , Hipertensão , Carne , Pessoa de Meia-Idade , Fatores de Risco , Taiwan
7.
Value Health ; 17(7): A765, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27202804
8.
Bioresour Technol ; 101(21): 8280-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20594829

RESUMO

This study elucidates the co-composting of biosolids and spent activated clay (SAC) using physio-chemical, bioassay, and spectroscopic methods. A pilot-scale pile of blended limed biosolids, SAC, and rice husk was composted for 15weeks. The changes in temperature, pH, Fourier-transform infrared (FT-IR) spectra, C/N, and germination index (GI) of Chinese cabbage (Brassica chinensis) seeds with time support the goal of producing a mature compost with a decline in the SAC acidity of associated with biosolids. Cadmium, Cr, Cu, Ni, and Pb in the initial biosolids were converted from labile fractions into relatively immobile phases upon maturation. Temperature, moisture, pH, C/N, and GI were used to separate the composting process into three phases - initial, thermophilic, and cooling, based on a score plot of principal component analysis (PCA). The values of the parameters of interest reveal that the compost fulfills the requirements of compost maturity in the literature.


Assuntos
Silicatos de Alumínio/química , Eliminação de Resíduos/métodos , Solo/análise , Brassica/crescimento & desenvolvimento , Carbono/análise , Fracionamento Químico , Argila , Germinação , Concentração de Íons de Hidrogênio , Metais Pesados/isolamento & purificação , Nitrogênio/análise , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Água
9.
Spinal Cord ; 48(9): 714-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20125109

RESUMO

STUDY DESIGN: A case report of silent myocardial ischemia in a man with C5 AIS A (American Spinal Injury Association Impairment Scale) tetraplegia during an episode of autonomic dysreflexia (AD). OBJECTIVE: The aim of this study was to show a clinical presentation of myocardial ischemia in individuals with spinal cord injury (SCI). CASE REPORT: A 45-year-old man with chronic C5 complete SCI presented with an episode of uncontrolled AD. He denied any symptoms of typical myocardial ischemia. Despite initiation of the AD management protocol, his blood pressure remained elevated. Additional testing revealed an unexpected horizontal ST depression in the lateral leads with a significant elevation of troponins. A follow-up cardiac angiography and MIBI cardiac perfusion scan revealed normal left ventricular contractility and no evidence of coronary artery occlusion. CONCLUSIONS: In individuals with SCI, the loss of sensory input from the myocardium to supraspinal structures predisposes them to asymptomatic myocardial ischemia. Furthermore, during an episode of AD, a significant increase in visceral sympathetic activity with coronary artery constriction can result in myocardial ischemia, even in the absence of coronary artery disease.


Assuntos
Disreflexia Autonômica/complicações , Disreflexia Autonômica/diagnóstico , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico , Disreflexia Autonômica/terapia , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/terapia , Quadriplegia/diagnóstico , Quadriplegia/etiologia , Traumatismos da Medula Espinal/terapia
10.
Ergonomics ; 51(3): 345-54, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18311611

RESUMO

The purpose of this study is to explore and assess manual material handling problems involving a vertical rope-pulling task from a scaffold (VRPS). Twenty-five young male Chinese subjects were recruited to participate in this study. The psychophysical method was used to investigate the effects of the rope material (nylon and hemp), rope diameter (6/8'' and 4/8''), object size (bucket diameter 28 cm and 36 cm), operating with and without gloves on the maximum acceptable rope-pulling weight (MAWR), rating of perceived exertion (RPE) and heart rate, respectively. The results showed that the maximum acceptable rope-pulling weights were significantly affected by the rope material, rope diameter, object size and wearing or not wearing gloves. The MAWR for the hemp rope, coarse rope, small object size and without gloves was significantly greater than that for the nylon rope, fine rope, large object size and with gloves, respectively. However, the effect of the rope material, rope diameter, object size and with and without gloves on heart rate was not significant. The mean RPE response was significantly influenced by the rope material, object size and wearing or not wearing gloves. The most stressed body parts were the arms, fingers and wrists. The interaction effect between the rope material and wearing or not wearing gloves was significant. Generally, the VRPS for workers using hemp rope without gloves or using nylon rope without gloves was better than that for the other combinations.


Assuntos
Ergonomia , Arquitetura de Instituições de Saúde , Sistemas Homem-Máquina , Esforço Físico , Postura , Suporte de Carga , Adulto , Fenômenos Biomecânicos , China , Humanos , Masculino , Exposição Ocupacional , Análise e Desempenho de Tarefas
11.
Skeletal Radiol ; 35(2): 95-102, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16189714

RESUMO

PURPOSE: The aim of this study was to test our observation that back pain in thalassemic patients could be caused by premature and extensive lumbar degenerative disc disease, when compared to non-thalassemic patients with back pain. METHODS AND MATERIALS: Sixteen thalassemic patients with their sex- and age-matched controls were recruited into the study, 12 with thalassemia major, and 4 with thalassemia intermedia. Both the thalassemia patients and control subjects suffered from back pain, which was subjective rather than measured/pain scored. All subjects underwent magnetic resonance (MR) imaging of the lumbar spine, and 11 of the cases and 8 controls had lumbar spine radiographs. Each lumbar disc was scored for radiographic appearances and MR features of disc degeneration and disc protrusion. Proportion values for these parameters and median scores were derived at each disc level, and were analyzed and compared. RESULTS: There was a statistically-significant difference between proportion values of cases and controls for the MR features (P value=0.01, n=16) and the radiographic features (P value=0.01, n=11 cases, n=8 controls) of disc degeneration. The median disc level scores for the thalassemic group were uniformly high across all lumbar discs, and at all levels except at L 4/5. The control group conversely demonstrated a predilection for disc degeneration at L4/5 level. CONCLUSION: The distribution of lumbar disc degeneration in thalassemic patients with back pain is more extensive, severe and multi-level in nature compared to matched controls, and disc degeneration should be considered as a significant cause of back pain in this population group.


Assuntos
Dor nas Costas/diagnóstico , Deslocamento do Disco Intervertebral/diagnóstico , Imageamento por Ressonância Magnética/estatística & dados numéricos , Radiografia/estatística & dados numéricos , Medição de Risco/métodos , Talassemia/diagnóstico , Dor nas Costas/epidemiologia , Estudos de Casos e Controles , Causalidade , Comorbidade , Humanos , Deslocamento do Disco Intervertebral/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Talassemia/epidemiologia , Reino Unido/epidemiologia
12.
Pediatr Surg Int ; 21(9): 730-2, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15977016

RESUMO

The simultaneous occurrence of intussusception and volvulus in the paediatric age group is rare. We report the case of a volvulus of an ileoileal intussusception in an 8-year-old boy. This is the first time that computerised tomography (CT) images of a volvulus of an ileoileal intussusception have been published, and they clearly demonstrate both pathologies. This case highlights the use of CT in determining the nature of an abdominal mass and demonstrates how helpful it can be in diagnosing the cause of small bowel obstruction in children.


Assuntos
Doenças do Íleo/etiologia , Volvo Intestinal/complicações , Intussuscepção/etiologia , Anastomose Cirúrgica , Criança , Diagnóstico Diferencial , Seguimentos , Humanos , Doenças do Íleo/diagnóstico por imagem , Doenças do Íleo/cirurgia , Volvo Intestinal/diagnóstico por imagem , Volvo Intestinal/cirurgia , Intussuscepção/diagnóstico por imagem , Intussuscepção/cirurgia , Masculino , Tomografia Computadorizada por Raios X
13.
J Food Prot ; 67(12): 2809-11, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15633692

RESUMO

Microbial contamination levels at broiler slaughter plants were investigated at three major slaughter plants in Taiwan during the summer and winter. The microbial contamination levels in chicken carcasses and on food contact surfaces were examined using the swab method. The results indicated that the bacterial counts were affected by the slaughter processing plant, processes, and season (P < 0.05). The bacterial counts on food contact surfaces of the equipment before operation were not significantly lower than those after processing. Regardless of the bacterial type, bacterial counts of chicken carcasses generally decreased from the scalding step to the washing step before evisceration and then increased. The cleaning procedures for food contact surfaces should be evaluated, and special attention should be given to utensils used during processing, such as gloves, baskets, and hand tools.


Assuntos
Matadouros , Galinhas/microbiologia , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Matadouros/normas , Animais , Contagem de Colônia Microbiana , Microbiologia Ambiental , Contaminação de Equipamentos , Microbiologia de Alimentos , Incidência , Estações do Ano , Taiwan
14.
Clin Hemorheol Microcirc ; 21(2): 99-103, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10599593

RESUMO

We exposed erythrocytes in soluble hemoglobin and Fe+2, in which hydroxyl radical (OH*) might be generated, and measured low shear rate viscosity and viscoelasticity of erythrocyte suspensions at Hct of 40%. The quantities of the lipid peroxidation product, malonyldialdehyde (MDA), for oxidized samples were higher than that for control (e.g., 2.20 +/- 0.46 nmol and 1.70 +/- 0.42 nmol, n = 6, p = 0.01, respectively). The viscosity values of oxidized erythrocyte suspensions for all tested shear rates were higher than those for the control samples (p < 0.05 or better, n = 6). Dynamic viscosity (eta') of oxidized erythrocyte samples was higher than that of control samples at the tested shear stress of 30 mPa whereas it was not observed in elasticity values (eta"). We tentatively concluded from the study, that oxidized erythrocytes would be more prone to form aggregates and increase viscosity of blood at low shear rates. Therefore, they might impair blood flow in the microcirculation.


Assuntos
Viscosidade Sanguínea/efeitos dos fármacos , Deformação Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Hemorreologia/efeitos dos fármacos , Estresse Oxidativo , Estresse Mecânico , Adulto , Elasticidade/efeitos dos fármacos , Membrana Eritrocítica/química , Membrana Eritrocítica/efeitos dos fármacos , Hemoglobinas/farmacologia , Humanos , Radical Hidroxila , Ferro/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/sangue , Fluidez de Membrana , Lipídeos de Membrana/química , Oxirredução , Espécies Reativas de Oxigênio
15.
Am J Kidney Dis ; 34(6): E27, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10585333

RESUMO

An 84-year-old man presented with ankle edema, significant proteinuria, and mild impairment of renal function soon after treatment was started for idiopathic myelofibrosis. Renal amyloidosis was found on biopsy. The amyloid deposit was resistant to potassium permanganate treatment and showed no immunoreactivity to immunoglobulin light chains, beta-amyloid protein, or amyloid A component. A review of the literature showed that the occurrence of amyloidosis in idiopathic myelofibrosis is very rare, and the chemical nature of the amyloid involved remains unclear.


Assuntos
Amiloidose/etiologia , Nefropatias/etiologia , Mielofibrose Primária/complicações , Idoso , Idoso de 80 Anos ou mais , Humanos , Rim/patologia , Nefropatias/patologia , Masculino
16.
Magn Reson Imaging Clin N Am ; 7(1): 23-37, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067221

RESUMO

The rotator interval between supraspinatus and subscapularis is proving to be an important anatomic and functional region of the shoulder. Appreciation of the anatomic structures, functional importance, and mechanisms of injury are invaluable in appropriate assessment, both by physical examination and diagnostic MR imaging. The long biceps tendon; the superior labrum and labral-biceps anchor; the coracohumeral ligament merging with the rotator interval capsule and the superior glenohumeral ligament; the ligamentous reflection pulley for the long biceps tendon at the far lateral margin of the interval extending to the lesser tuberosity and proximal bicipital groove, bounded by the distal superior margin of the subscapularis and anterior margin of the supraspinatus tendons; and the transverse humeral ligament extending between the lesser and greater tuberosities along the proximal bicipital groove all are intimately associated in this region and may be injured together. Understanding of the anatomy and function of the rotator interval continues to evolve. Rotator interval injury may be better understood as a complex or spectrum rather than an isolated lesion. When any one of the spectrum of associated injuries is suspected or found, all of the other possible associated injuries should be considered and evaluated, both on clinical and MR imaging evaluations.


Assuntos
Traumatismos em Atletas/diagnóstico , Imageamento por Ressonância Magnética , Lesões do Manguito Rotador , Lesões do Ombro , Traumatismos dos Tendões/diagnóstico , Feminino , Humanos , Masculino
17.
Magn Reson Imaging Clin N Am ; 7(1): 39-49, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067222

RESUMO

In conclusion, internal impingement apparently occurs in nearly all patients and is demonstrable on MR imaging. Pathologic changes associated with internal impingement seem to develop with repetitive placement of the arm into a position of extreme external rotation and abduction. Findings may include lesions of the posterior superior labrum, undersurface irritation, or tearing of the supraspinatus-infraspinatus junction near the attachment site and cystic changes of the posterior superior glenoid and posterior lateral greater tuberosity. There is no evidence for a particular sequence of pathologic changes. Instability may be associated with but does not appear to be a prerequisite for the development of the pathologic lesions of internal impingement.


Assuntos
Beisebol/lesões , Imageamento por Ressonância Magnética , Síndrome de Colisão do Ombro/diagnóstico , Lesões do Ombro , Entorses e Distensões/diagnóstico , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino
18.
Magn Reson Imaging Clin N Am ; 7(1): 73-84, viii, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067224

RESUMO

"Skier's thumb" is an acute rupture of the ulnar collateral ligament (UCL) of the metacarpophalangeal (MCP) joint of the thumb. As the method of choice in evaluating soft tissue injuries, MR imaging is useful in evaluating UCL injuries. This article reviews current concepts regarding the rupture of the UCL, including a study of 34 UCL injuries in which MR imaging was used as the main diagnostic tool. When correlated with surgical findings, MR imaging resulted in identifying UCL tears with 96% sensitivity and 95% specificity.


Assuntos
Ligamentos Colaterais/lesões , Imageamento por Ressonância Magnética , Articulação Metacarpofalângica/lesões , Esqui/lesões , Polegar/lesões , Adulto , Estudos Transversais , Método Duplo-Cego , Feminino , Humanos , Masculino , Ruptura , Sensibilidade e Especificidade
19.
Magn Reson Imaging Clin N Am ; 7(1): 117-30, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067227

RESUMO

Tears of the ACL have become widespread in the skiing population. Understanding of the mechanisms and patterns of associated injury of such ACL tears has benefited from and contributed greatly to clinical and imaging evaluation and management. MR imaging of the injured knee has become the gold standard comprehensive imaging examination for evaluating the ACL tear and associated soft-tissue and osseous injuries and assisting the treating physician in planning management, as the isolated ACL tear has proven to be the exception rather than the rule in skiing knee injuries.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho/diagnóstico , Imageamento por Ressonância Magnética , Esqui/lesões , Ligamentos Colaterais/lesões , Feminino , Humanos , Articulação do Joelho/patologia , Masculino , Ligamento Cruzado Posterior/lesões
20.
Magn Reson Imaging Clin N Am ; 7(1): 175-90, ix, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10067230

RESUMO

This article discusses the effectiveness of MR imaging in evaluating the injuries of both upper and lower extremities in the professional football player. Topics include bone, joint and soft tissue disorders, and injuries resulting from overuse or trauma of the shoulder, elbow, forearm, and wrist; the pelvis and hip, lower extremity muscle and tendon, knee, and ankle.


Assuntos
Futebol Americano/lesões , Imageamento por Ressonância Magnética , Traumatismos do Braço/diagnóstico , Humanos , Traumatismos da Perna/diagnóstico , Masculino , Traumatismos dos Tendões/diagnóstico
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