Atomic Configuration of Point Defect Clusters in Ion-Irradiated Silicon Carbide.

Silicon Carbide (SiC) is a promising cladding material for accident-tolerant fuel in light water reactors due to its excellent resistance to chemical attacks at high temperatures, which can prevent severe accident-induced environmental disasters. Although it has been known for decades that radiation-induced swelling at low temperatures is driven by the formation of black spot defects with sizes smaller than 2 nm in irradiated SiC, the structure of these defect clusters and the mechanism of lattice expansion have not been clarified and remain as one of the most important scientific issues in nuclear materials research. Here we report the atomic configuration of defect clusters using Cs-corrected transmission electron microscopy and molecular dynamics to determine the mechanism of these defects to radiation swelling. This study also provides compelling evidence that irradiation-induced point defect clusters are vacancy-rich clusters and lattice expansion results from the homogenous distribution of unrecovered interstitials in the material.

Monitoring and assessment of heavy metal contamination in a constructed wetland in Shaoguan (Guangdong Province, China): bioaccumulation of Pb, Zn, Cu and Cd in aquatic and terrestrial components.

The objective of this study is to evaluate the current status of heavy metal concentrations in constructed wetland, Shaoguan (Guangdong, China). Sediments, three wetland plants (Typha latifolia, Phragmites australis, and Cyperus malaccensis), and six freshwater fish species [Carassius auratus (Goldfish), Cirrhinus molitorella (Mud carp), Ctenopharyngodon idellus (Grass carp), Cyprinus carpio (Wild common carp), Nicholsicypris normalis (Mandarin fish), Sarcocheilichthys kiangsiensis (Minnows)] in a constructed wetland in Shaoguan were collected and analyzed for their heavy metal compositions. Levels of Pb, Zn, Cu, and Cd in sediments exceeded approximately 532, 285, 11, and 66 times of the Dutch Intervention value. From the current study, the concentrations of Pb and Zn in three plants were generally high, especially in root tissues. For fish, concentrations of all studied metals in whole body of N. mormalis were the highest among all the fishes investigated (Pb 113.4 mg/kg, dw; Zn 183.1 mg/kg, dw; Cu 19.41 mg/kg, dw; 0.846 mg/kg, dw). Heavy metal accumulation in different ecological compartments was analyzed by principle component analysis (PCA), and there is one majority of grouped heavy metals concentration as similar in composition of ecological compartment, with the Cd concentration quite dissimilar. In relation to future prospect, phytoremediation technology for enhanced heavy metal accumulation by constructed wetland is still in early stage and needs more attention in gene manipulation area.

Clinical value of transforaminal epidural steroid injection in lumbar radiculopathy.

OBJECTIVES: To identify the diagnostic, therapeutic, and prognostic values of transforaminal epidural steroid injection as interventional rehabilitation for lumbar radiculopathy. SETTING: Regional hospital, Hong Kong. PATIENTS: A total of 232 Chinese patients with lumbar radiculopathy attributed to disc herniation or spinal stenosis received transforaminal epidural steroid injection between 1 January 2007 and 31 December 2011. INTERVENTIONS: Transforaminal epidural steroid injection. MAIN OUTCOME MEASURES: Patients' immediate response, response duration, proportion of patients requiring surgery, and risk factors affecting the responses to transforaminal epidural steroid injection for lumbar radiculopathy. RESULTS: Of the 232 patients, 218 (94.0%) had a single level of radiculopathy and 14 (6.0%) had multiple levels. L5 was the most commonly affected level. The immediate response rate to transforaminal epidural steroid injection was 80.2% in 186 patients with clinically diagnosed lumbar radiculopathy and magnetic resonance imaging of the lumbar spine suggesting nerve root compression. Of patients with single-level radiculopathy and multiple-level radiculopathy, 175 (80.3%) and 11 (78.6%) expressed an immediate response to transforaminal epidural steroid injection, respectively. The analgesic effect lasted for 1 to <3 weeks in 35 (15.1%) patients, for 3 to 12 weeks in 37 (15.9%) patients, and for more than 12 weeks in 92 (39.7%) patients. Of the 232 patients, 106 (45.7%) were offered surgery, with 65 (61.3%) undergoing operation, and with 42 (64.6%) requiring spinal fusion in addition to decompression surgery. Symptom chronicity was associated with poor immediate response to transforaminal epidural steroid injection, but not with duration of pain reduction. Poor response to transforaminal epidural steroid injection was not associated with a preceding industrial injury. CONCLUSIONS: The immediate response to transforaminal epidural steroid injection was approximately 80%. Transforaminal epidural steroid injection is a useful diagnostic, prognostic, and short-term therapeutic tool for lumbar radiculopathy. Although transforaminal epidural steroid injection cannot alter the need for surgery in the long term, it is a reasonably safe procedure to provide short-term pain relief and as a preoperative assessment tool.

Nurse-led orthopaedic clinic in total joint replacement.

OBJECTIVES: To introduce the practice of a nurse-led orthopaedic clinic for managing stable patients after total hip or knee replacement and to evaluate its efficacy. DESIGN: Case series. SETTING: A public hospital in Hong Kong. PATIENTS: Patients who had stable primary total knee replacement or total hip replacement done for longer than 2 years were managed in a nurse-led total joint replacement pilot clinic. RESULTS: From July 2012 to March 2014, 431 patients (including 317 with total knee replacement and 114 with total hip replacement) were handled, and 408 (94.7%) nurse assessments were independently performed. Six cases of prosthesis-related complications were diagnosed. One patient was hospitalised for prosthetic complications within 3 months after follow-up. The satisfaction rate was 100%. From November 2012 to April 2013, an advanced practice nurse, one resident specialist, and one associate consultant independently charted Knee Society Knee Score or Harris Hip Score for the patients attending preoperative assessment clinic to check the inter-observer reliability. Overall, 23 patients with 37 knees and 11 patients with 17 hips were examined. The mean correlation coefficient between assessments by the associate consultant and advanced practice nurse was 0.912 for Knee Society Knee Score, and 0.761 for Harris Hip Score. The advanced practice nurse could achieve better or equally good correlation with associate consultant when compared with the correlation between resident specialist and associate consultant (0.866 and 0.521 for Knee Society Knee Score and Harris Hip Score, respectively) and with international standard. CONCLUSION: Nurse-led total joint replacement clinic was safe, reliable, and well accepted by patients.

Serum concentrations of brain-derived neurotrophic factor (BDNF) are decreased in colorectal cancer patients.

OBJECTIVE: To determine the usefulness of brain-derived neurotrophic factor (BDNF) as a diagnostic biomarker for colorectal cancer (CRC). MATERIALS AND METHODS: ELISA immunoassay was used to examine BDNF concentrations in the sera of two different retrospective cohorts consisting of CRC patients and age/gender matched controls. Cohort 1 consisted of 99 controls and 97 CRC patients, whereas cohort 2 consisted of 47 controls and 91 CRC patients. RESULTS: In cohort 1, the median concentration of BDNF was significantly (p< 0.0001) lower in CRC patient samples (18.8 ng/mL, range 4.0-56.5 ng/mL) than control samples (23.4 ng/mL, range 3.0-43.1 ng/mL). This finding was validated in an independent patient cohort (CRC patients: 23.0 ng/mL, range 6.0-45.9 ng/mL; control patients: 32.3 ng/mL, range 14.2-62.4 ng/mL). BDNF concentrations did not differ significantly between Dukes' staging in the patient cohort, however patients with Stages A, B, C and D (p< 0.01 for each stage) tumours had significantly reduced BDNF levels compared to healthy controls. Receiver operating characteristic analysis was performed to determine the ability of BDNF to discriminate between healthy controls and those with CRC. At 95% specificity, BDNF concentrations distinguished CRC patients with 25% and 18% sensitivity, respectively, in cohorts 1 and 2 (cohort 1: AUC=0.79, 95% CI 0.70-0.87; cohort 2: AUC =0.69, 95% CI 0.61-0.76). CONCLUSION: The serum levels of BDNF were significantly lower in colorectal cancer patients when compared to a control population, and this did not differ between different Dukes' stages.

A modified dynamic evolving neural-fuzzy approach to modeling customer satisfaction for affective design.

Affective design is an important aspect of product development to achieve a competitive edge in the marketplace. A neural-fuzzy network approach has been attempted recently to model customer satisfaction for affective design and it has been proved to be an effective one to deal with the fuzziness and non-linearity of the modeling as well as generate explicit customer satisfaction models. However, such an approach to modeling customer satisfaction has two limitations. First, it is not suitable for the modeling problems which involve a large number of inputs. Second, it cannot adapt to new data sets, given that its structure is fixed once it has been developed. In this paper, a modified dynamic evolving neural-fuzzy approach is proposed to address the above mentioned limitations. A case study on the affective design of mobile phones was conducted to illustrate the effectiveness of the proposed methodology. Validation tests were conducted and the test results indicated that: (1) the conventional Adaptive Neuro-Fuzzy Inference System (ANFIS) failed to run due to a large number of inputs; (2) the proposed dynamic neural-fuzzy model outperforms the subtractive clustering-based ANFIS model and fuzzy c-means clustering-based ANFIS model in terms of their modeling accuracy and computational effort.

Autologous osteochondral graft for traumatic defects of finger joints.

Finger joint defects in 16 adults were treated with an autologous osteochondral graft from the base of the second metacarpal, the radial styloid, the base of the third metacarpal or the trapezoid and these patients were followed up from between 12 and 62 months. There was no donor site morbidity. One patient had resorption of the graft and developed pain. The joint was subsequently fused. The mean range of movement was 55.8% of the opposite normal joint. At follow up, 15 patients had no discomfort or mild discomfort. Three had mild narrowing of the joint space and two had slight joint subluxation. Only two patients with concomitant severe injury to the same limb had difficulty performing daily activities. Ten were open injuries and these had poorer outcomes. A hemicondylar defect of a finger joint can be treated using an osteochondral graft obtained from the same hand.

Disseminated amyloidosis presenting with right proximal femur pathological fracture in a haemodialysis end-stage renal failure patient.

Osteoarticular amyloidosis can be one of the musculoskeletal system manifestations related to dialysis. We share our experience in dealing with a case of disseminated haemodialysis-associated amyloidosis in a 74-year-old end-stage renal failure patient. This patient suffered from a serious complication, namely an unprovoked pathological fracture at the basal neck region of the right femur. Polyarticular cystic and lytic lesions over the contralateral proximal femur, bilateral proximal humerus and the right lunate were noted on further imaging. In view of extensive amyloidotic infiltration into the proximal femur as well as the acetabulum, a cemented total hip arthroplasty operation was performed for pain relief and restoration of function. The radiological investigations, diagnostic challenges, operative as well as histopathological findings are discussed. This disease should be considered in the differential diagnosis of pathological juxta-articular fracture in patients undergoing haemodialysis.

Unusual traumatic triceps tendon avulsion rupture: a word of caution.

Triceps tendon rupture is a rare condition. The usual mechanism of injury is a fall on an outstretched hand, although direct contact injuries have also been reported to cause this injury. A 67-year-old woman presented with injuries caused by direct impact to her right elbow after a fall. X-rays of the elbow demonstrated the cardinal clinical 'gap' and 'flake' signs. It is necessary to be aware of this injury and perform a careful examination at the time of the initial presentation, as the signs of this injury are usually subtle. Most reported primary repairs have been performed with non-absorbable transosseous sutures. In this case report, we show how using suture anchors for reattachment is a technically feasible alternative operative method providing a good surgical outcome.

Infection in primary total knee replacement.

OBJECTIVES: To determine the infection rate and identify the risk factors of primary total knee replacement in a general hospital and discuss possible preventive measure. DESIGN: Retrospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: All cases of primary total knee replacement performed between the period July 1997 and June 2006 were reviewed. MAIN OUTCOME MEASURES: Infection rate of primary total knee replacement and its relationship to risk factors. RESULTS: In the defined period, 479 total knee replacements were performed in 353 patients (291 female and 62 male); 105 women and 21 men had bilateral replacements. The mean patient age was 69 (range, 40-88) years. In all, 447 knees had osteoarthritis, and 32 had rheumatoid arthritis. The mean follow-up period was 46 (range, 1-107) months; 345 knees were followed up longer than 24 months, but seven had no postoperative follow-up. Wound infection was defined by clinical, bacteriological, and/or histological examination. Primary total knee replacement was invariably performed in a theatre with vertical laminar flow, under prophylactic antibiotic cover, and body exhaust suits, water impermeable gowns, and double gloves were always used. The overall infection rate was 3.0% (14/472); the acute deep infection rate (within 4 weeks) was 0.2% (1/472), the delayed deep infection rate (4 weeks-2 years) was 0.6% (2/345). The superficial infection rate was 1.9% (9/472) and the late deep infection rate (after 2 years) was 0.6% (2/345). Diabetic patients had a three-fold higher risk of infection than non-diabetic patients, though this difference did not attain statistical significance (P=0.077). CONCLUSIONS: Our infection rates for primary total knee replacement were comparable to those encountered internationally.

Crystal arthropathy of the lumbar spine: a report of 4 cases.

Gout or pseudogout, caused by deposition of crystals, rarely affects the spine. We report 4 cases with gout or pseudogout in the lumbar spine. Two had cauda equina syndrome and another 2 had spinal stenosis. To avoid unnecessary surgery, this should be considered in the differential diagnosis when treating patients with histories of gout or pseudogout for spinal problems.

Management of malignant atlanto-axial tumours.

PURPOSE: To review the management and outcomes of patients with malignant tumours of the atlanto-axial spine treated over a 4-year period at a tertiary hospital. METHODS: A total of 12 patients (9 female and 3 male) with a mean age of 56.5 years (range, 35-71 years) were consecutively enrolled. At the time of presentation, 7 patients had received treatment for a known primary malignancy of the lung (n=4), colon (n=1), nasopharynx (n=1), or breast (n=1). The atlanto-axial spine was the first presentation of malignant disease in the remaining 5 patients, whose subsequent diagnoses were multiple myeloma (n=1), carcinoma of the thyroid (n=1), malignant fibrous histiocytoma (n=2), and adenocarcinoma of unknown origin (n=1). Preoperative, postoperative, and follow-up radiographs and computed tomographic and magnetic resonance imaging scans were analysed with regard to the extent of tumour involvement, other spinal metastases, instability, and evidence of cord compression. Surgeries were performed for surgically fit patients with a life expectancy of more than 3 months. RESULTS: All patients presented with severe suboccipital neck pain. Two had mild neurological deficits (Frankel grade D). Two patients were treated conservatively with rigid neck collars and survived for 3 and 11 months. Surgical stabilisation with posterior instrumentation was performed in 10 patients. One patient received additional anterior surgery for tumour debulking and bone grafting. No neurological complications were recorded in the series. Excellent relief of pain was achieved, and the mean visual analogue scale pain score of the operated patients improved from 9.3 to 1.9. The mean survival of 9 patients after surgery was 13.1 months, while one patient was still living at the time of review (at postoperative 11 months). CONCLUSION: Surgical stabilisation in selected patients provided pain relief and preserved ambulatory status before the deterioration of overall function.

Air pollution and daily hospitalization rates for cardiovascular and respiratory diseases in London, Ontario.

In this paper, we examine the role that ambient air pollution plays in exacerbating cardiovascular and respiratory disease hospitalization in London, Ontario from 1 November 1995 to 31 December 2000. The number of daily cardiac and respiratory admissions was linked to concentrations of air pollutants (sulphur dioxide, nitrogen dioxide, ozone, carbon monoxide, coefficient of haze, PM(10)) and weather variables (maximum and minimum of temperature and humidity). Results showed that current day carbon monoxide and coefficient of haze produced significant percentage increase in daily cardiac admissions of 8.0% (95% CI: 1.5-11.5%) and 5.7% (95% CI: 0.9-10.8%) for people < 65 years old. PM(10) was found to be significantly associated with asthma admission in the > 65 group, with percentage increase in cardiac admission of 25% (95% CI: 2.8-52.3%) and 26.0% (95% CI: 5.3-50.9%) for current day and 2-day means, respectively.

Proteomic analysis of multiple sclerosis cerebrospinal fluid.

Two-dimensional gel electrophoresis and peptide mass fingerprinting were used to identify proteins in cerebrospinal fluid (CSF) pooled from three patients with multiple sclerosis (MS) and in CSF pooled from three patients with non-MS inflammatory central nervous system (CNS) disorders. Resolution of CSF proteins on three pH gradients (3-10, 4-7 and 6-11) enabled identification of a total of 430 spots in the MS CSF proteome that represented 61 distinct proteins. The gels containing MS CSF revealed 103 protein spots that were not seen on control gels. All but four of these 103 spots were proteins known to be present in normal human CSF. The four exceptions were: CRTAC-IB (cartilage acidic protein), tetranectin (a plasminogen-binding protein), SPARC-like protein (a calcium binding cell signalling glycoprotein), and autotaxin t (a phosphodiesterase). It remains unknown whether these four proteins are related to the cause and pathogenesis of MS.

Rapid on-site defibrillation versus community program.

INTRODUCTION: For patients who suffer out-of-hospital cardiac arrest, the time from collapse to initial defibrillation is the single most important factor that affects survival to hospital discharge. The purpose of this study was to compare the survival rates of cardiac arrest victims within an institution that has a rapid defibrillation program with those of its own urban community, tiered EMS system. METHODS: A logistic regression analysis of a retrospective data series (n = 23) and comparative analysis to a second retrospective data series (n = 724) were gathered for the study period September 1994 to September 1999. The first data series included all persons at Casino Windsor who suffered a cardiac arrest. Data collected included: age, gender, death/survival (neurologically intact discharge), presenting rhythm (ventricular fibrillation (VF), ventricular tachycardia (VT), or other), time of collapse, time to arrival of security personnel, time to initiation of cardiopulmonary resuscitation (CPR) prior to defibrillation (when applicable), time to arrival of staff nurse, time to initial defibrillation, and time to return of spontaneous circulation (if any). Significantly, all arrests within this series were witnessed by the surveillance camera systems, allowing time of collapse to be accurately determined rather than estimated. These data were compared to those of similar events, times, and intervals for all patients in the greater Windsor area who suffered cardiac arrest. This second series was based upon the Ontario Prehospital Advanced Life Support (OPALS) Study database, as coordinated by the Clinical Epidemiology Unit of the Ottawa Hospital, University of Ottawa. RESULTS: The Casino Windsor had 23 cases of cardiac arrests. Of the cases, 13 (56.5%) were male and 10 (43.5%) were female. All cases (100%) were witnessed. The average of the ages was 61.1 years, of the time to initial defibrillation was 7.7 minutes, and of the time for EMS to reach the patient was 13.3 minutes. The presenting rhythm was VF/VT in 91% of the case. Fifteen patients were discharged alive from hospital for a 65% survival rate. The Greater Windsor Study area included 668 cases of out-of-hospital cardiac arrest: Of these, 410 (61.4%) were male and 258 (38.6%) were female, 365 (54.6%) were witnessed, and 303 (45.4%) were not witnessed. The initial rhythm was VF/VT was in 34.3%. Thirty-seven (5.5%) were discharged alive from the hospital. CONCLUSION: This study provides further evidence that PAD Programs may enhance cardiac arrest survival rates and should be considered for any venue with large numbers of adults as well as areas with difficult medical access.

Robust active control of broadband noise in finite ducts.

This study focuses on robust active control of broadband noise in finite ducts. Our analytical and experimental studies suggest the existence of several technical flaws in the path models of conventional active noise control (ANC) systems. These are sensitivity of the path model with respect to boundary conditions, and nonminimum phase (NMP) secondary and reference paths. For finite ducts with small cross sections, the traveling wave model (TWM) may be adopted to find an effective solution to these problems and lead to a robust ANC system. Since many practical "noisy" ducts are finite with small cross sections, the proposed ANC has many practical applications. Its robustness and ability to suppress broadband noise will be explained theoretically and verified experimentally.

Recurrent BRCA1 and BRCA2 germline mutations in ovarian cancer: a founder mutation of BRCA1 identified in the Chinese population.

Previous mutational analysis for BRCA gene mutations in sporadic ovarian cancer occurring in Chinese patients in Hong Kong identified six germline BRCA1 mutations and one germline BRCA2 mutation, six of which were novel (Khoo et al., 2000). Knowledge of BRCA gene mutations in the Chinese population is relatively scant. In this study, we focussed on whether any of these mutations could be recurrent in our Chinese population, making use of archival paraffin embedded tissue. A consecutive series of 214 ovarian cancer cases, half of Southern Chinese origin from Hong Kong whilst the other half of Northern Chinese origin from Beijing were used for the study. We identified one further novel mutation, 1081delG, in BRCA1. This was found to occur in two unrelated individuals with shared haplotype as revealed by allelotype analysis, thus demonstrating founder effect. Two other recurrent mutations were also identified, the 2371-2372delTG mutation in BRCA1 and the 3337C>T mutation in BRCA2 recurring in two and three unrelated individuals respectively, giving an overall prevalence 4.7% of recurrent BRCA mutations in ovarian cancer in the Southern Chinese population. Most importantly, all our recurrent mutation carriers were identified from Southern Chinese patients from Hong Kong whilst such mutations were absent in samples from the Northern Chinese. Our findings indicate possible heterogeneity in the BRCA genotype between Northern and Southern Chinese. The identification of a founder mutation and two recurrent mutations moreover, has important implications towards screening strategies for breast and ovarian cancer among Chinese of southern ancestral origin who are now dispersed throughout the world.

Beliefs and perceptions of patients with acne.

BACKGROUND: There is a paucity of information on the knowledge and understanding of patients with acne about their condition. OBJECTIVE: The objective of this study is to evaluate the knowledge, beliefs, and perceptions of acne patients regarding their understanding of acne pathogenesis, sources of information, treatment options, and expectations. METHODS: Patients referred to a community-based dermatologist for management of acne vulgaris completed a self-administered questionnaire. Responses were correlated with demographic and clinical information. RESULTS: Seventy-four percent of patients waited more than 1 year before seeking medical attention for acne. Nonprescription products used most frequently were cleansers, acne pads, and lotions. Acne was most often believed to be caused by hormonal and genetic factors, although diet, poor skin hygiene, and infection were also implicated. Information on acne was obtained primarily from family physicians, mass media, friends, and family, but was largely believed to be inadequate. Acne was believed to be curable by 49% of patients with an anticipated treatment duration of less than 6 months. Male patients and those with severe acne preferred systemic therapy compared with female patients and those with lesser grades of acne. CONCLUSION: There is a need for accessible, accurate, community-based education on the natural history of acne, pathogenesis, risk of sequelae, the effectiveness and expected duration of treatment, and the importance of prompt medical attention.