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The construction of super-large tunnels generates various safety risks that can hamper the tunneling process and cause severe damages if not properly identified. This paper presents a case study on the identification and management of geological and environmental risks during the construction of the largest (a diameter of 15.8 m) slurry shield tunnel in China. Its ground conditions and settlement control were identified among the most challenging owing to a large area of mixed ground conditions, 11 fault zones and tunneling under residential areas and the city’s Metro Lines 1 and 9. In response to the severity of these risks and challenges, novel monitoring systems, ground treatment, and safety management technologies were successfully implemented throughout the tunneling process. Further, a technical framework was proposed in this study to serve as a risk management guidance for analogous tunneling operations.

Background:. In 2007, a randomized controlled trial (RCT) by the Canadian Orthopaedic Trauma Society (COTS) demonstrated better functional outcomes and a lower proportion of patients who developed malunion or nonunion following operative, compared with nonoperative, treatment of midshaft clavicle fractures. The primary aim of the present study was to compare the proportion of midshaft clavicle fractures treated operatively prior to and following the publication of the COTS RCT. An additional exploratory aim was to assess whether the proportion of midshaft clavicle fractures that were treated with surgery for malunion or nonunion decreased. Methods:. This retrospective cohort analysis used population-level administrative health data on the residents of British Columbia, Canada. Cases were identified by International Classification of Diseases, Ninth Revision (ICD-9) diagnostic codes and procedure fee codes. Adult patients (≥18 years) with closed middle-third clavicle fractures between 1997 and 2018 were included. Multivariable logistic regression modeling compared the proportion of clavicle fractures treated operatively before and after January 1, 2007, controlling for patient factors. The Pearson chi-square test compared the proportion of fractures treated operatively for malunion or nonunion in the cohorts. Results:. A total of 52,916 patients were included (mean age, 47.5 years; 65.6% male). More clavicle fractures were treated operatively from 2007 onward: 6.9% compared with 2.2% prior to 2007 (odds ratio [OR] = 3.35, 95% confidence interval [CI] = 3.03 to 3.70, p < 0.001). Male sex, moderate-to-high income, and younger age were associated with a greater proportion of operative fixation. The rate of surgery for clavicle malunion or nonunion also increased over this time period (to 4.1% from 3.4%, OR = 1.26, 95% CI = 1.15 to 1.38, p < 0.001). Conclusions:. We found a significant change in surgeon practice regarding operative management of clavicle fractures following the publication of a Level-I RCT. With limited high-quality trials comparing operative and nonoperative management, it is important that clinicians, health-care institutions, and health-authority administrations determine what steps can be taken to increase responsiveness to new clinical studies and evidence-based guidelines. Level of Evidence:. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Femoral fractures due to sideways falls continue to be a major cause of concern for the elderly. Existing approaches for the prevention of these injuries have limited efficacy. Prophylactic femoral augmentation systems, particularly those involving the injection of ceramic-based bone cements, are gaining more attention as a potential alternative preventative approach. We evaluated the mechanical effectiveness of three variations of a bone cement injection pattern (basic ellipsoid, hollow ellipsoid, small ellipsoid) utilizing finite element simulations of sideways fall impacts. The basic augmentation pattern was tested with both high- and low-strength ceramic-based cements. The cement patterns were added to the finite element models (FEMs) of five cadaveric femurs, which were then subject to simulated sideways falls at seven impact velocities ranging from 1.0 m/s to 4.0 m/s. Peak impact forces and peak acetabular forces were examined, and failure was evaluated using a strain-based criterion. We found that the basic HA ellipsoid provided the highest increases in both the force at the acetabulum of the impacted femur (“acetabular force”, 55.0% ± 22.0%) and at the force plate (“impact force”, 37.4% ± 15.8%). Changing the cement to a weaker material, brushite, resulted in reduced strengthening of the femur (45.2% ± 19.4% acetabular and 30.4% ± 13.0% impact). Using a hollow version of the ellipsoid appeared to have no effect on the fracture outcome and only a minor effect on the other metrics (54.1% ± 22.3% acetabular force increase and 35.3% ± 16.0% impact force increase). However, when the outer two layers of the ellipsoid were removed (small ellipsoid), the force increases that were achieved were only 9.8% ± 5.5% acetabular force and 8.2% ± 4.1% impact force. These results demonstrate the importance of supporting the femoral neck cortex to prevent femoral fractures in a sideways fall, and provide plausible options for prophylactic femoral augmentation. As this is a preliminary study, the surgical technique, the possible effects of trabecular bone damage during the augmentation process, and the effect on the blood supply to the femoral head must be assessed further.

A novel and effective artificial neural network (ANN) optimized using differential evolution (DE) is first introduced to provide a robust and reliable forecasting of jet grouted column diameters. The proposed computational method adopts the DE algorithm to tackle the difficulties in the training and performance of neural networks and optimize the four quintessential hyper-parameters (i.e. the epoch size, the number of neurons in a hidden layer, the number of hidden layers, and the regularization parameter) that govern the neural network efficacy. This approach is further enhanced by a stochastic gradient optimization algorithm to allow ‘expensive’ computation efforts. The ANN-DE is first trained using a prepared jet grouting dataset, then verified and compared with the prevalent machine learning tools, i.e. neural networks and support vector machine (SVM). The results show that, the ANN-DE outperforms the existing methods for predicting the diameter of jet grouting columns since it well balances training efficiency and model performance. Specifically, the ANN-DE achieved root mean square error (RMSE) values of 0.90603 and 0.92813 for the training and testing phases, respectively. The corresponding values were 0.8905 and 0.9006 for the optimized ANN, then, 0.87569 and 0.89968 for the optimized SVM, respectively. The proposed paradigm is bound to be useful for solving various geotechnical engineering problems regardless of multi-dimension and nonlinearity.

Recent large meta-analyses suggested a poorer long-term patients’ and grafts’ outcomes after ABO incompatible (ABOi) living-donor kidney transplantation (LDKT) compared to ABO compatible LDKT. However, little is known about the long-term histological pattern after ABOi LDKT. We compared the histological features observed on protocol biopsies from 03/11 to 11/19 in 94 ABOi LDKT (including 14 with preformed Donor Specific Antibodies, pDSAs), 27 LDKT ABO compatible (ABOc) with pDSAs, and 21 ABOc without pDSAs) during the first five years post transplantation. During the first 5 years post-transplantation, a progression of chronic lesions (patients with a ci >0 raised from 11% to 65%, p0 raised from 29% to 78%, p

Abstract Background Competing demands for operative resources may affect time to hip fracture surgery. We sought to determine the time to hip fracture surgery by variation in demand in Canadian hospitals. Methods We obtained discharge abstracts of 151,952 patients aged 65 years or older who underwent surgery for a hip fracture between January, 2004 and December, 2012 in nine Canadian provinces. We compared median time to surgery (in days) when demand could be met within a two-day benchmark and when demand required more days, i.e. clearance time, to provide surgery, overall and stratified by presence of medical reasons for delay. Results For persons admitted when demand corresponded to a 2-day clearance time, 68% of patients underwent surgery within the 2-day benchmark. When demand corresponded to a clearance time of one week, 51% of patients underwent surgery within 2 days. Compared to demand that could be served within the two-day benchmark, adjusted median time to surgery was 5.1% (95% confidence interval [CI] 4.1–6.1), 12.2% (95% CI 10.3–14.2), and 22.0% (95% CI 17.7–26.2) longer, when demand required 4, 6, and 7 or more days to clear the backlog, respectively. After adjustment, delays in median time to surgery were similar for those with and without medical reasons for delay. Conclusion Increases in demand for operative resources were associated with dose-response increases in the time needed for half of hip fracture patients to undergo surgery. Such delays may be mitigated through better anticipation of day-to-day supply and demand and increased response capability.

This study presents an evaluation of climate and land-use changes induced impacts on water resources of Multan City, Pakistan. Statistical Down Scaling Model (SDSM) and Geographical Information System (GIS) are used for climate change scenario and spatial analyses. Hydrologic Engineering Center’s Hydraulic Modeling System (HEC-HMS) model is used for rainfall-runoff simulation. The investigated results show significant changes in climatological parameters, i.e., an increase in temperature and decrease in precipitation over the last 40 years, and a significant urban expansion is also observed from 2000 to 2020. The increase in temperature and urbanization has reduced the infiltration rate into the soil and increased the runoff flows. The HEC-HMS results indicate that surface runoff gradually increased over the last two decades. Consequently, the depth of the water table in the shallow aquifer has declined by about 0.3 m/year. Projected climate indices stipulate that groundwater depletion will occur in the future. Arsenic levels have exceeded the permissible limit owing to unplanned urban expansion and open dumping of industrial effluents. The results can help an efficient water resources management in Multan.

The data presented in this paper pertain to case records of liquefaction potential surveys in earthquake prone areas. Field performances of 219 sites obtained from various regions (U.S.A, Japan, Turkey, China, Canada, etc …) are put on display. Specifically, this database consists of 253 cone penetration test (CPT) field records, among which 72 cases that did not liquefied and 181 cases that liquefied. In total, 10 principal variables are tabulated including the earthquake magnitude, maximum ground surface acceleration, depth, water depth, total overburden stress, effective overburden stress, Cone Penetration Test (CPT) tip resistance, CPT friction ratio, fines content, shear stress ratio. These data were arbitrarily split into a testing set of 53 cases and a training set of 200 cases. These field observations are compared to prediction values of liquefaction potential assessed using the evolutionary neural network proposed for “Evaluation of soil liquefaction with AI technology incorporating a coupled ENN/t-SNE model” [1]. Keywords: Liquefaction, Database, CPT, Neural network

Purpose: To evaluate the effect of comprehensive geriatric management on physical function after hip fracture. Materials and methods: This was a parallel-group 1:1 single-blinded randomized controlled trial. Fifty-three older adults (≥ 65 years) 3 to 12 months after hip fracture were randomized through a web-based system (independent statistical company) into usual care or usual care plus intervention (B4). The B4 group received management by a geriatrician, physical therapist and other health professionals. Outcomes were: Leg (knee extension) and grip strength, timed up and go; and self-report function at baseline, 6 and 12 months (blinded assessment). We estimated between-group differences at 6 and 12 months using linear mixed models, and compared function between groups with a global statistical test (incorporating the five measures). Results: There were no statistically significant differences between groups. For the combined sample, strength on the fractured leg (2.63, 95% CI: 0.86, 4.40 kg) and non-fractured leg (1.36, 95% CI: 0.12, 2.70 kg) were statistically higher than baseline values. Conclusions: There were no between group differences in physical function. Overall, older adults from both groups had small significant improvements in bilateral leg strength at final assessment, but below age-matched normative values.

The collapse of a 30-year-old hotel building in Suzhou, Jiangsu Province on 12 July 2021 raised legitimate questions about the identification of old buildings’ condition and risks stemming from remedial operations. This short communication reports and investigates the causes of this accident, which led to 17 deaths and 5 injuries. Subsequently, it describes the rescue actions undertaken, including logistic means, operational strategies, and procedure sequencing. The causes of the accident were attributed to: (i) the poor quality and fragility of the building, (ii) illegal renovations and extensions, as well as (iii) the laxism of relevant departments that failed to timely check the risk level of the building before these renovations. Thanks to efficient organization and management, the rescue operations were completed within 42 h. Based on this preliminary analysis, some recommendations are proposed to prevent similar incidents in the future.

A huge gas explosion occurred on 13 June 2021 in Shiyan City, China, resulting in 25 casualties and serious injuries to 37 people. The main victims of this explosion were stall keepers and customers buying breakfast and fresh vegetables in the food market. There is a continuous need to enhance the understanding of such unfortunate events, given the dangers they pose. This study analyzes the causes of this accident considering the general background and scenes of the explosion, and then describes the rescue operations undertaken. The investigation results revealed that the explosion was caused by the poor maintenance of gas facilities and negligence of safety regulations. It is, therefore, recommended that the control of these two main aspects be strengthened to reduce the recurrence of such unfortunate accidents.

Background: This study performed a psychometric analysis assessing and comparing the responsiveness of the relevant components of a generic (Short Form–36 [SF36]), a musculoskeletal-specific (Short Musculoskeletal Functional Assessment [SMFA]), and a foot and ankle–specific (Foot and Ankle Outcome Score [FAOS]) outcome score when evaluating surgically treated tibial plafond fractures over time. Methods: Fifty-one patients were followed for 12 months after their tibial plafond fracture. Responsiveness, or the ability to detect clinical change in a disease, was evaluated through the standardized response mean (SRM), the proportion meeting a minimal clinically important difference (MCID), and floor and ceiling effects. Results: The SRM of the SF36–Physical Component Summary (PCS) was significantly greater than the SMFA–dysfunction index (DI) ( P < .01) and FAOS–Activities of Daily Living (ADL) ( P = .01) between baseline and 6 months, whereas the SRMs of only SF36-PCS and FAOS-ADL differed ( P = .01) between 6 and 12 months. The proportion of patients achieving an MCID for SF36-PCS was higher than FAOS-ADL ( P = .03) between baseline and 6 months and higher than SMFA-DI ( P = .04) between 6 and 12 months. The FAOS-ADL showed substantial ceiling effects at baseline (88.2%) but much less at 6 months (5.9%) and 12 months (9.8%). Smaller ceiling effects were observed for the SMFA-DI (11.8%) at baseline, whereas none were observed for the SF36-PCS. Conclusions: This study found that the SF36-PCS had greater responsiveness in assessing tibial plafond fractures compared to the SMFA-DI and FAOS-ADL, particularly in the first 6 months after surgery. In addition, limitations were revealed in the SMFA-DI and FAOS-ADL. This study illustrates the necessary diligence required for selection of outcome measures, as musculoskeletal and anatomy specific scores are not necessarily superior. Level of Evidence: Level II, prospective cohort study.

This paper presents a comprehensive review on subsea jet trenching technology via a critical analysis of its principle, mechanism, devices, modeling approaches, as well as properties of subsea sediments. This review shows that the success of jet trenching operations is closely related to some key factors including the soil conditions, trencher specifications, and characteristics of pipelines or cables. Three case histories are presented to demonstrate the importance of these key factors and their interrelationships. This paper also points out a number of challenges pertaining to the implementation of the jet trenching method in carbonate sediments, as well as some limitations and gaps in the existing modeling approaches. Future perspective researches that are recommended to develop: (1) promising theories, like turbulent submerged flow, and (2) robust numerical approaches, such as the smoothed particle hydrodynamics (SPH) and material point method (MPM) to substantiate the experimental experience and reveal possible hidden mechanisms.

The majority of hip fractures have been reported to occur as a result of a fall with impact to the greater trochanter of the femur. Recently, we developed a novel cadaveric pendulum-based hip impact model and tested two cadaveric femur-pelvis constructs, embedded in a soft tissue surrogate. The outcome was a femoral neck fracture in a male specimen while a female specimen had no fracture. The aim of the present study was, first, to develop a methodology for constructing and assessing the accuracy of explicit Finite Element Models (FEMs) for simulation of sideways falls to the hip based on the experimental model. Second, to use the FEMs for quantifying the internal reaction forces and energy absorption in the hip during impact. Third, to assess the potential of the FEMs in terms of separating a femoral fracture endpoint from a non-fracture endpoint. Using a non-linear, strain rate dependent, and heterogeneous material mapping strategy for bone tissue in these models, we found the FEM-derived results to closely match the experimental test results in terms of impact forces and displacements of pelvic video markers up to the time of peak impact force with errors below 10%. We found the internal reaction forces in the femoral neck on the impact side to be approximately 35% lower than the impact force measured between soft tissue and ground for both specimens. In addition, we found the soft tissue to be the component that absorbed the largest part of the energy of the tissue types in the hip region. Finally, we found surface strain patterns derived from FEM results to match the fracture location and extent based on post testing x-rays of the specimens. This is the first study with quantitative data on the energy absorption in the pelvic region during a sideways fall.

[This corrects the article DOI: 10.1371/journal.pone.0200952.].

Falls to the side are the leading cause of hip fractures in the elderly. The load that a person experiences during a fall cannot be measured with volunteers for ethical reasons. To evaluate injurious loads, while considering relevant energy input and body posture for a sideways fall, a subject-specific cadaveric impact experiment was developed. Full cadaveric femur-pelvis constructs (N = 2) were embedded in surrogate soft tissue material and attached to metallic surrogate lower limbs. The specimens were then subjected to an inverted pendulum motion, simulating a fall to the side with an impact to the greater trochanter. The load at the ground and the deformation of the pelvis were evaluated using a 6-axis force transducer and two high-speed cameras. Post-test, a trauma surgeon (PG) evaluated specimen injuries. Peak ground contact forces were 7132 N and 5641 N for the fractured and non-fractured specimen, respectively. We observed a cervical fracture of the femur in one specimen and no injuries in a second specimen, showing that the developed protocol can be used to differentiate between specimens at high and low fracture risk.

Objective: To test the effect of a follow-up clinic on urinary incontinence (UI) and nocturia among older adults with hip fracture. Method: Fifty-three older adults (≥65 years) 3 to 12 months following hip fracture were enrolled and randomized to receive usual care plus the intervention (B4), or usual care (UC) only. The B4 group received management by health professionals, with need-based referrals. UI, nocturia, and quality of life were measured with questionnaires at baseline, 6 months, and 12 months. Results: There were 48 participants included in this analysis, and at baseline, 44% of study participants self-reported UI. At final assessment, six out of 24 B4 participants and 12 out of 24 UC participants reported UI. Four out of five study participants reported nocturia at baseline; this did not decrease during the study. Discussion : Following hip fracture, many older adults report UI and most report nocturia. Health professionals should be aware of the high occurrence of urinary symptoms among older adults post hip fracture.