Effects of Auditory Training in Older Adults.

PURPOSE: This study examines the effects of an auditory training program on the auditory and cognitive abilities of older adults. Auditory rehabilitation programs are generally designed for hearing aid users, and studies have demonstrated benefits for them. In this study, we seek to understand whether such a training program can also benefit older adults who do not wear hearing aids. We also examined if cognitive benefits can indeed be observed as a result of the training. METHOD: Sixty-four older adults were recruited and assigned into three groups: the experimental group (n = 20), the active control group (n = 21), and the no-training control group (n = 23). The experimental group underwent an auditory training program (Listening and Communication Enhancement [LACE]) during the training phase. Meanwhile, the active control group listened to short audio clips and the no-training control group did not participate in any program. An auditory test (Quick Speech-in-Noise [QuickSIN]) and a battery of cognitive tests were conducted before and after the training to examine the participants' performance on auditory ability, short-term memory, and attention. RESULTS: The results showed improvements in auditory and cognitive abilities during the training period. When assessing the training effects by comparing the pre- and the posttraining performances, a significant improvement on the QuickSIN task was found in the training group but not in the other two groups. However, other cognitive tests did not show any significant improvement. That is, the LACE training did not benefit short-term memory and attention. The improved performance on short-term memory during the training was not maintained in the posttraining session. CONCLUSION: Overall, the study has extended the auditory benefit from the LACE training to the typical aging population in terms of improved communication ability, but the effect of training on auditory abilities did not transfer to gains in cognitive abilities.

Early Complication Rates Are Equivalent Between Isolated Cartilage Restoration and Concomitant Cartilage Restoration and Osteotomy of the Knee.

OBJECTIVE: Realignment osteotomy performed concomitantly with cartilage restoration typically requires early restricted weightbearing and can add significant morbidity, potentially leading to an increased risk of early perioperative complications. The purpose of this study was to compare the 30-day complication rates after isolated cartilage restoration (ICR) versus concomitant cartilage restoration and osteotomy (CRO) using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. DESIGN: NSQIP registries between 2006 and 2019 were queried using Current Procedural Terminology codes to identify patients undergoing ICR (autologous chondrocyte implantation, osteochondral autograft transfer, or osteochondral allograft transplantation) and CRO (with concomitant high tibial osteotomy, distal femoral osteotomy, and/or tibial tubercle osteotomy). Complications rates between treatment groups were compared using multivariate logistic regression analyses adjusted for sex, age, steroid use, and respiratory status. RESULTS: A total of 773 ICR and 97 CRO surgical procedures were identified. Mean patient ages were 35.9 years for the ICR group and 31.2 years for the CRO group. Operative time was significantly longer in the CRO group (170.8 min) compared with the ICR group (97.8 min). Multivariate analysis demonstrated no significant differences in rates of PE, VTE, and all-cause readmission between the ICR and CRO groups. No events of wound disruption, SSI and reoperation were found in the CRO group, while the ICR group was characterized by low rates of wound disruption, reoperation, and SSI (<1.1%). CONCLUSIONS: These findings further support concomitant osteotomy with cartilage restoration when appropriate and aid surgeons in the preoperative counseling of patients undergoing cartilage restoration treatment.

Enduring musician advantage among former musicians in prosodic pitch perception.

Musical training has been associated with various cognitive benefits, one of which is enhanced speech perception. However, most findings have been based on musicians taking part in ongoing music lessons and practice. This study thus sought to determine whether the musician advantage in pitch perception in the language domain extends to individuals who have ceased musical training and practice. To this end, adult active musicians (n = 22), former musicians (n = 27), and non-musicians (n = 47) were presented with sentences spoken in a native language, English, and a foreign language, French. The final words of the sentences were either prosodically congruous (spoken at normal pitch height), weakly incongruous (pitch was increased by 25%), or strongly incongruous (pitch was increased by 110%). Results of the pitch discrimination task revealed that although active musicians outperformed former musicians, former musicians outperformed non-musicians in the weakly incongruous condition. The findings suggest that the musician advantage in pitch perception in speech is retained to some extent even after musical training and practice is discontinued.

Native Language Perceptual Sensitivity Predicts Nonnative Speech Perception Differently in Younger and Older Singaporean Bilinguals.

PURPOSE: We investigate in this study how individual variability in native language speech perception (termed Perceptual Sensitivity) influences nonnative speech perception in Singaporean Tamil-English bilinguals. Further, we assess if and how contextual and demographic factors influence Perceptual Sensitivity in the acquired languages and if the influence of Perceptual Sensitivity on nonnative speech perception is different across younger and older bilinguals. METHOD: Perceptual Sensitivity in the native languages was examined by implementing Tamil and English gating tasks in 87 Singaporean Tamil-English bilinguals from two age groups (younger: 19-33 years; older: 55-70 years). Mandarin lexical tone discrimination was implemented as a measure of nonnative speech perception. RESULTS: There was a wide range of variability in Perceptual Sensitivity scores in both languages across both age groups. Perceptual Sensitivity in the first native language (L1 Tamil) was a robust predictor of nonnative speech perception across both age groups, especially for the older bilinguals. However, general intelligence emerged as a stronger predictor than Tamil Perceptual Sensitivity in younger bilinguals. The influence of Tamil Perceptual Sensitivity on lexical tone perception was not tone-specific, supporting a general enhancement of lexical tone perception with better Tamil Perceptual Sensitivity. There was an influence of demographic factors on English Perceptual Sensitivity in older bilinguals, but not for Tamil and not in younger bilinguals. CONCLUSIONS: Our findings corroborate with previous studies in showing that native language Perceptual Sensitivity is positively associated with and predicts nonnative speech perception in younger and older adulthood regardless of language similarity but to varying degrees. Specifically, the influence of Perceptual Sensitivity on nonnative speech perception is stronger in older adulthood, suggesting a possible shift in reliance on crystallized language knowledge with age. Proficiency and use, among other demographic and language variables, do not appear to influence L1 Perceptual Sensitivity in a lesser used language (Tamil) as significantly as previously assumed.

A BF3 -Doped MXene Dual-Layer Interphase for a Reliable Lithium-Metal Anode.

A dual-layer interphase that consists of an in-situ-formed lithium carboxylate organic layer and a thin BF3 -doped monolayer Ti3 C2 MXene on Li metal is reported. The honeycomb-structured organic layer increases the wetting of electrolyte, leading to a thin solid electrolyte interface (SEI). While the BF3 -doped monolayer MXene provides abundant active sites for lithium homogeneous nucleation and growth, resulting in about 50% reduced thickness of inorganic-rich components among the SEI layer. A low overpotential of less than 30 mV over 1000 h cycling in symmetric cells is received. The functional BF3  groups, along with the excellent electronic conductivity and smooth surface of the MXene, greatly reduce the lithium plating/stripping energy barrier, enabling a dendrite-free lithium-metal anode. The battery with this dual-layer coated lithium metal as the anode displays greatly improved electrochemical performance. A high capacity-retention of 175.4 mAh g-1 at 1.0 C is achieved after 350 cycles. In a pouch cell with a capacity of 475 mAh, the battery still exhibits a high discharge capacity of 165.6 mAh g-1 with a capacity retention of 90.2% after 200 cycles. In contrast to the fast capacity decay of pure Li metal, the battery using NCA as the cathode also displays excellent capacity retention in both coin and pouch cells. The dual-layer modified surface provides an effective approach in stabilizing the Li-metal anode.

The Impact of Financial Assistance Programs on Health Care Utilization: Evidence from Kaiser Permanente.

Most hospitals have financial assistance programs for low-income patients. We use administrative data from Kaiser Permanente to study the effects of financial assistance on healthcare utilization. Using a regression discontinuity design based on an income threshold for program eligibility, we find that financial assistance increases the likelihood of an inpatient, ambulatory and emergency department encounter by 3.6 pp (59%), 13.4 pp (20%), and 6.7 pp (53%), respectively, though effects dissipate three quarters after program receipt. Financial assistance also increases the detection and management of treatment-sensitive conditions (e.g., drugs treating diabetes), suggesting financial assistance may increase receipt of high-value care.

Individual differences in nonnative lexical tone perception: Effects of tone language repertoire and musical experience.

This study sought to understand the effects of tone language repertoire and musical experience on nonnative lexical tone perception and production. Thirty-one participants completed a tone discrimination task, an imitation task, and a musical abilities task. Results showed that a larger tone language repertoire and musical experience both enhanced tone discrimination performance. However, the effects were not additive, as musical experience was associated with tone discrimination performance for single-tone language speakers, but such association was not seen for dual-tone language speakers. Furthermore, among single-tone language speakers, but not among dual-tone language speakers, musical experience and musical aptitude positively correlated with tone discrimination accuracy. It is thus concluded that individuals with varying extents of tone language experience may adopt different strategies when performing tone discrimination tasks; single-tone language speakers may draw on their musical expertise while dual-tone language speakers may rely on their extensive tone language experience instead.

Chronic obstructive pulmonary disease and the modulation of CFTR by acute exposure to cigarette smoke.

Chronic obstructive pulmonary disease (COPD) is a leading cause of death and cigarette smoke is the main risk factor. Detecting its earliest stages and preventing a decline in lung function are key goals. The pathogenesis of COPD is complex but has some similarities to cystic fibrosis (CF), a disease caused by mutations in the cftr gene. CF leads to chronic inflammation, abnormal mucus, and cycles of infection. Cigarette smoke exposure also causes CFTR dysfunction, and it is probably not a coincidence that inflammation, mucus obstruction, and infections are also characteristics of COPD, although the exacerbations can be quite different. We review here the acute effects of cigarette smoke on CFTR function and its potential role in COPD. Understanding CFTR regulation by cigarette smoke may identify novel drug targets and facilitate the development of therapeutics that reduce the progression and severity of COPD.

Trends in Medical Debt During the COVID-19 Pandemic.

This cross-sectional study evaluates the association between the COVID-19 pandemic and reported new medical debt from 2018 to 2021 across the US.

A Scoping Review on the Medical and Recreational Use of Cannabis During the COVID-19 Pandemic.

Background/Introduction: The shelter-in-place orders and social distancing regulations on account of the COVID-19 pandemic have impacted lifestyles, including the use of cannabis. The purpose of this scoping review is to summarize both the gray and academic literature on the use of cannabis during the pandemic. Materials and Methods: A total of 11 databases, including 2 medical databases, 7 social science databases, and 2 gray literature databases were searched resulting in 316 titles and abstracts of which 76 met inclusion criteria. Results: Nine themes emerged: (a) prevalence and trends of cannabis use during COVID[1]19; (b) demographics; (c) profile of mode of consumption; (d) context of using cannabis (i.e., solitary use vs. in groups); (e) factors contributing to use; (f) factors inhibiting use; (g) adverse clinical and psychiatric outcomes of cannabis use during the pandemic; (h) similarities between EVALI (E-Cigarette or Vaping Product Use-Associated Lung Injury) and COVID-19 symptoms; (i) implications for policy and practice. Studies published until February 2, 2021 were included in this review. Discussion: Findings have highlighted that feelings of boredom, depression, and anxiety during the pandemic have contributed to an increase in the use of cannabis. Furthermore, accessibility to cannabis was noted to affect use during the pandemic. Adverse psychiatric and clinical outcomes were associated with the increased use of cannabis. Conclusion: Practitioners and policymakers are called to employ harm reduction strategies to respond to increasing cannabis use. There is a need for population-based studies and further examination of factors contributing to the increased use of cannabis during the pandemic and associated negative consequences.

Medical Debt in the US, 2009-2020.

Importance: Medical debt is an increasing concern in the US, yet there is limited understanding of the amount and distribution of medical debt, and its association with health care policies. Objective: To measure the amount of medical debt nationally and by geographic region and income group and its association with Medicaid expansion under the Affordable Care Act. Design, Setting, and Participants: Data on medical debt in collections were obtained from a nationally representative 10% panel of consumer credit reports between January 2009 and June 2020 (reflecting care provided prior to the COVID-19 pandemic). Income data were obtained from the 2014-2018 American Community Survey. The sample consisted of 4.1 billion person-month observations (nearly 40 million unique individuals). These data were used to estimate the amount of medical debt (nationally and by geographic region and zip code income decile) and to examine the association between Medicaid expansion and medical debt (overall and by income group). Exposures: Geographic region (US Census region), income group (zip code income decile), and state Medicaid expansion status. Main Outcomes and Measures: The stock (all unpaid debt listed on credit reports) and flow (new debt listed on credit reports during the preceding 12 months) of medical debt in collections that can be collected on by debt collectors. Results: In June 2020, an estimated 17.8% of individuals had medical debt (13.0% accrued debt during the prior year), and the mean amount was $429 ($311 accrued during the prior year). The mean stock of medical debt was highest in the South and lowest in the Northeast ($616 vs $167; difference, $448 [95% CI, $435-$462]) and higher in poor than in rich zip code income deciles ($677 vs $126; difference, $551 [95% CI, $520-$581]). Between 2013 and 2020, the states that expanded Medicaid in 2014 experienced a decline in the mean flow of medical debt that was 34.0 percentage points (95% CI, 18.5-49.4 percentage points) greater (from $330 to $175) than the states that did not expand Medicaid (from $613 to $550). In the expansion states, the gap in the mean flow of medical debt between the lowest and highest zip code income deciles decreased by $145 (95% CI, $95-$194) while the gap increased by $218 (95% CI, $163-$273) in the nonexpansion states. Conclusions and Relevance: This study provides an estimate of the amount of medical debt in collections in the US based on consumer credit reports from January 2009 to June 2020, reflecting care delivered prior to the COVID-19 pandemic, and suggests that the amount of medical debt was highest among individuals living in the South and in lower-income communities. However, further study is needed regarding debt related to COVID-19.

Longitudinal study of BK Polyomavirus outcomes, risk factors, and kinetics in renal transplantation patients.

BACKGROUND: In the immunocompromised conditions following renal transplantation, BK virus can reactivate and cause BK virus associated nephropathy (BKVN). Increased BK viral loads and extended duration of infection have been linked to development of BKVN. The aim of this study was to observe the incidence of BKV infection and BKVN, and kinetics of infection and disease in renal transplantation recipients. METHODS: From 2014 to 2018, we conducted a longitudinal cohort observational study of 139 renal transplantation patients treated at a single clinic. Quantitative PCR assay was conducted to assess longitudinal BK viral loads. Analysis of patient clinical characteristics was performed to determine risk factors for BKV infection and associated disease. RESULTS: Of our cohort, 29 (20.9%) patients developed high BK viremia, and 7 (5.0%) developed biopsy-confirmed BKVN. Clinical parameters associated with diabetes (FBS, HbA1c) and hyperlipidemia (TG, TC, LDL-C) were found to be correlated with development of high BK viremia or BKVN. In 3 of 4 patients receiving intravenous immunoglobulin (IVIG) treatment, BK viral loads were reduced by at least 1 log within 2-3 months of administration. Significant differences were measured in BK viral loads and kidney function between BK viremic patients and BKVN patients by 3-9 months post-transplantation. CONCLUSIONS: We identified diabetes and hyperlipidemia as potential risk factors for development of high BK viremia and/or BKVN. IVIG was seen to be effective in reducing viral titers. The period 3-9 months post-transplantation was identified as important for development of BKVN from high BK viremia.

The Difference between Computed Tomography and Magnetic Resonance Imaging Measurements of Tibial Tubercle-Trochlear Groove Distance for Patients with or without Patellofemoral Instability: A Systematic Review and Meta-analysis.

The tibial tubercle-trochlear groove (TT-TG) distance was originally described for computed tomography (CT) but has recently been used on magnetic resonance imaging (MRI) without sufficient evidence demonstrating its validity on MRI. The current review aims to evaluate (1) whether there is a difference in the TT-TG distances measured using CT and MRI, (2) whether both the TT-TG distances measured using CT and MRI could be used to differentiate between patients with or without patellofemoral instability, and (3) whether the same threshold of 15 to 20 mm can be applied for both TT-TG distances measured using CT and MRI. The review was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRSIMA) guidelines. All studies that compared TT-TG distances either (1) between CT and MRI or (2) between patients with and without patellofemoral instability were included. A total of 23 publications were included in the review. These included a total of 3,040 patients. All publications reported the TT-TG distance to be greater in patients with patellofemoral instability as compared to those without patellofemoral instability. This difference was noted for both TT-TG distances measured on CT and on MRI. All publications also reported the TT-TG distance measured on CT to be greater than that measured on MRI (mean difference [MD] = 1.79 mm; 95% confidence interval [CI]: 0.91-2.68). Pooling of the studies revealed that the mean TT-TG distance for the control group was 12.85 mm (95% CI: 11.71-14.01) while the mean TT-TG distance for patients with patellofemoral instability was 18.33 mm (95% CI: 17.04-19.62) when measured on CT. When measured on MRI, the mean TT-TG distance for the control group was 9.83 mm (95% CI: 9.11-10.54), while the mean TT-TG distance for patients with patellofemoral instability was 15.33 mm (95% CI: 14.24-16.42). Both the TTTG distances measured on CT and MRI could be used to differentiate between patients with and without patellofemoral instability. Patients with patellofemoral instability had significantly greater TT-TG distances than those without. However, the TT-TG distances measured on CT were significantly greater than that measured on MRI. Different cut-off values should, therefore, be used for TT-TG distances measured on CT and on MRI in the determination of normal versus abnormal values. Pooling of all the patients included in the review then suggest for 15.5 ± 1.5 mm to be used as the cut off for TT-TG distance measured on CT, and for 12.5 ± 2 mm to be used as the cut-off for TT-TG distance measured on MRI. The Level of evidence for this study is IV.

Reduction of Physiological Strain Under a Hot and Humid Environment by a Hybrid Cooling Vest.

Chan, APC, Yang, Y, Wong, FKW, Yam, MCH, Wong, DP, and Song, W-F. Reduction of physiological strain under a hot and humid environment by a hybrid cooling vest. J Strength Cond Res 33(5): 1429-1436, 2019-Cooling treatment is regarded as one of good practices to provide safe training conditions to athletic trainers in the hot environment. The present study aimed to investigate whether wearing a commercial lightweight and portable hybrid cooling vest that combines air ventilation fans with frozen gel packs was an effective means to reduce participants' body heat strain. In this within-subject repeated measures study, 10 male volunteers participated in 2 heat-stress trials (one with the cooling vest-COOL condition, and another without-CON condition, in a randomized order) inside a climatic chamber with a controlled ambient temperature 33° C and relative humidity (RH) 75% on an experimental day. Each trial included a progressively incremental running test, followed by a 40-minute postexercise recovery. Core temperature (Tc), heart rate (HR), sweat rate (SR), rating of perceived exertion (RPE), exercise duration, running distance, and power output were measured. When comparing the 2 conditions, a nonstatistically significant moderate cooling effect in rate of increase in Tc (0.03 ± 0.02° C·min for COOL vs. 0.04 ± 0.02° C·min for CON, p = 0.054, d = 0.57), HR (3 ± 1 b·min·min for COOL vs. 4 ± 1 b·min·min for CON, p = 0.229, d = 0.40), and physiological strain index (PSI) (0.20 ± 0.06 unit·min for COOL vs. 0.23 ± 0.06 unit·min for CON, p = 0.072, d = 0.50) was found in the COOL condition during exercise. A nonstatistically significant (p > 0.05) trivial cooling effect (d < 0.2) was observed between the COOL and CON conditions for measures of exercise duration, running distance, power output, SR, and RPE. It is concluded that the use of the hybrid cooling vest achieved a moderate cooling effect in lowering the rate of increase in physiological strain without impeding the performance of progressively incremental exercise in the heat.

Five-Strand Hamstring Autograft in Primary Anterior Cruciate Ligament Reconstruction.

The purpose of this study was to describe our surgical technique of using five-strand hamstring autograft with interference screw fixation in primary anterior cruciate ligament (ACL) reconstruction and to report the early postoperative outcomes of this technique. Patients who underwent primary ACL reconstruction using five-strand hamstring autografts with interference screw fixation between December 2014 and June 2016 were included in this study. The five-strand configuration was used in these patients because the four-strand configuration produced a graft diameter of less than 8 mm. Subjective questionnaires, including the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm Score, were administered preoperatively, as well as at 1- and 2-year follow-ups. Paired t-test was used to compare the pre- and postoperative outcome scores. The study group comprised 25 patients. There were no intraoperative complications. The mean follow-up period was 17.8 months (12-24). There were 19 males and 6 females. The median age was 24 years (16-41), and median body mass index was 23.9 (18.5-30.2). The median diameter of the five-strand graft was 9 mm (8-10 mm), with a mean of 9.06 ± 0.60 mm. This was associated with a median graft length of 90 mm (80-100 mm). The postoperative Lysholm, KOOS symptoms, KOOS Pain, KOOS daily function, KOOS sports function, KOOS quality of life, and Short Form-36 Physical Component Summary scores improved significantly compared with the preoperative scores. The use of the five-strand hamstring graft with interference screw fixation in primary ACL reconstruction is associated with significant improvements in patient-reported outcomes in the early postoperative period. The five-strand graft technique is a useful means of increasing graft diameter when faced with an undersized hamstring graft.

A Bayesian Network Model for Reducing Accident Rates of Electrical and Mechanical (E&M) Work.

Accidents in Repair, Maintenance, Alteration, and Addition (RMAA) work have become a growing concern, in recent years. The repair and maintenance works of electrical and mechanical (E&M) installations involves a variety of trades, a large number of practitioners and a series of high-risk activities. The uniqueness of E&M work, in the RMAA sector, requires a discrete and specific research to improve its safety performance. Understanding the causal relationships between safety factors and the number of accidents becomes crucial to develop a more effective safety management strategy. The Bayesian Network (BN) model is proposed to establish a probabilistic relational network between the causal factors, including both safety climate factors and personal experience factors that have influences on the number of accidents related to E&M RMAA work. The data were collected using a survey questionnaire, involving a hundred and fifty-five E&M practitioners. The BN results demonstrated that safety attitude and safety procedures were the most important factors to reduce the number of accidents. The proposed BN provides the ability to find out the most effective strategy with the best utilization of resources, to reduce the chance of a high number of E&M accidents, by controlling a single factor or simultaneously controlling, both, the safety climate and personal factors, to improve safety performance.

Quantitative in vivo whole genome motility screen reveals novel therapeutic targets to block cancer metastasis.

Metastasis is the most lethal aspect of cancer, yet current therapeutic strategies do not target its key rate-limiting steps. We have previously shown that the entry of cancer cells into the blood stream, or intravasation, is highly dependent upon in vivo cancer cell motility, making it an attractive therapeutic target. To systemically identify genes required for tumor cell motility in an in vivo tumor microenvironment, we established a novel quantitative in vivo screening platform based on intravital imaging of human cancer metastasis in ex ovo avian embryos. Utilizing this platform to screen a genome-wide shRNA library, we identified a panel of novel genes whose function is required for productive cancer cell motility in vivo, and whose expression is closely associated with metastatic risk in human cancers. The RNAi-mediated inhibition of these gene targets resulted in a nearly total (>99.5%) block of spontaneous cancer metastasis in vivo.

Use of the 5-Strand Hamstring Autograft Technique in Increasing Graft Size in Anterior Cruciate Ligament Reconstruction.

BACKGROUND: To determine the extent to which a strategy of routinely preparing a 5-strand hamstring autograft would increase graft size in anterior cruciate ligament (ACL) reconstruction. METHODS: A total of 64 patients were enrolled in a prospective randomized controlled study comparing 5-strand and quadrupled semitendinosus-gracilis autografts in single-bundle ACL reconstruction (5-strand group, n = 32; 4-strand group, n = 32). In the 5-strand group, the diameter of the 4-strand construct and the subsequent 5-strand graft used were measured, whereas in the 4-strand group, the diameter of the quadrupled graft used was measured. Quadrupled graft diameter and hamstring tendon lengths were correlated with patient gender, height, weight, and body mass index (BMI). RESULTS: The mean diameter of the final graft used in the 5-strand group was 8.8 ± 0.8 mm, whereas that in the 4-strand group was 7.8 ± 0.7 mm (P < .001). The mean increase in graft size achieved with the use of the 5-strand technique was 1.4 ± 0.3 mm. In the 5-strand group, 24 of 32 (75%) patients had graft diameters exceeding 8 mm compared with 9 of 32 (28%) patients in the 4-strand group (P < .001). Quadrupled graft diameter was significantly correlated with patient height and BMI, whereas the gracilis and semitendinosus lengths were significantly correlated with patient height. CONCLUSIONS: The 5-strand hamstring autograft provides a significantly larger diameter graft compared with the quadrupled hamstring autograft in ACL reconstruction. Graft sizes exceeding 8 mm are achievable in 75% of patients with the routine application of this technique. This is significantly more than that obtained with the standard quadrupled hamstring graft. Hamstring tendon length and quadrupled hamstring graft diameter are also significantly correlated with patient height. LEVEL OF EVIDENCE: Level 1, prospective randomized controlled trial.

Accidents of Electrical and Mechanical Works for Public Sector Projects in Hong Kong.

A study on electrical and mechanical (E&M) works-related accidents for public sector projects provided the opportunity to gain a better understanding of the causes of accidents by analyzing the circumstances of all E&M works accidents. The research aims to examine accidents of E&M works which happened in public sector projects. A total of 421 E&M works-related accidents in the "Public Works Programme Construction Site Safety and Environmental Statistics" (PCSES) system were extracted for analysis. Two-step cluster analysis was conducted to classify the E&M accidents into different groups. The results identified three E&M accidents groups: (1) electricians with over 15 years of experience were prone to 'fall of person from height'; (2) electricians with zero to five years of experience were prone to 'slip, trip or fall on same level'; (3) air-conditioning workers with zero to five years of experience were prone to multiple types of accidents. Practical measures were recommended for each specific cluster group to avoid recurrence of similar accidents. The accident analysis would be vital for industry practitioners to enhance the safety performance of public sector projects. This study contributes to filling the knowledge gap of how and why E&M accidents occur and promulgating preventive measures for E&M accidents which have been under researched.