Why Does Cross-Sectional Analyst Coverage Incorporate Market-Wide Information?

This paper shows that the empirical distribution of cross-sectional analyst coverage in China's stock markets follows an exponential law in a given month from 2011 to 2020. The findings hold in both the emerging (Shanghai) and the developed market (Hong Kong). Moreover, the unique distribution parameter (i.e., mean) is directly related to the amount of market-wide information. Average analyst coverage exhibits a significant negative predictive power for stock-market uncertainty, highlighting the role of security analysts in diminishing the total uncertainty. The exponential law can be derived from the maximum entropy principle (MEP). When analysts, who are constrained by average ability in generating information (i.e., the first-order moment), strive to maximize the amount of market-wide information, this objective yields the exponential distribution. Contrary to the conventional wisdom that security analysts specialize in the generation of firm-specific information, empirical findings suggest that analysts primarily produce market-wide information for 25 countries. Nevertheless, it remains unclear why cross-sectional analyst coverage reflects market-wide information, this paper provides an entropy-based explanation.

Video dataset of sheep activity for animal behavioral analysis via deep learning.

A primary dataset capturing five distinct types of sheep activities in realistic settings was constructed at various resolutions and viewing angles, targeting the expansion of the domain knowledge for non-contact virtual fencing approaches. The present dataset can be used to develop non-invasive approaches for sheep activity detection, which can be proven useful for farming activities including, but not limited to, sheep counting, virtual fencing, behavior detection for health status, and effective sheep breeding. Sheep activity classes include grazing, running, sitting, standing, and walking. The activities of individuals, as well as herds of sheep, were recorded at different resolutions and angles to provide a dataset of diverse characteristics, as summarized in Table 1. Overall, a total of 149,327 frames from 417 videos (the equivalent of 59 minutes of footage) are presented with a balanced set for each activity class, which can be utilized for robust non-invasive detection models based on computer vision techniques. Despite a decent existence of noise within the original data (e.g., segments with no sheep present, multiple sheep in single frames, multiple activities by one or more sheep in single as well as multiple frames, segments with sheep alongside other non-sheep objects), we provide original videos and the original videos' frames (with videos and frames containing humans omitted for privacy reasons). The present dataset includes diverse sheep activity characteristics and can be useful for robust detection and recognition models, as well as advanced activity detection models as a function of time for the applications.

Gender Control of Mouse Embryos by Activation of TLR7/8 on X Sperm via Ligands dsRNA-40 and dsRNA-DR.

Gender control technologies are promising for enhancing the production efficiency of the farm animal industry, and preventing sex-linked hereditary diseases in humans. It has been shown that the X sperm of mammalian animals specifically expresses X-chromosome-derived toll-like receptor 7/8 (TLR7/8), and the activation of TLR7/8 on the X sperm by their agonist, R848, can separate X and Y sperm via the specific inhibition of X sperm motility. The use of R848-preselected sperm for fertilization resulted in sex-ratio-skewed embryos or offspring. In this study, we aimed to investigate whether two other TLR7/8 ligands, double-stranded RNA-40 (dsRNA-40) and double-stranded RNA-DR (dsRNA-DR), are also effective in the separation of mouse X and Y sperm and the subsequent generation of gender-ratio-skewed in vitro fertilization (IVF) embryos. Our results indicated that cholesterol modification significantly enhances the transfection of dsRNA-40 and dsRNA-DR into sperm cells. dsRNA-40 and dsRNA-DR incubation with mouse sperm could separate X and Y sperm by the specific suppression of X sperm motility by decreasing its ATP level and mitochondrial activity. The use of a dsRNA-40- or dsRNA-DR-preselected upper layer of sperm, which predominantly contains high-motility Y sperm, for IVF caused a male-biased sex ratio shift in resulting embryos (with 65.90-74.93% of embryos being male). This study develops a simple new method for the efficient separation of mammalian X and Y sperm, enabling the selective production of male or female progenies.

Meshless Search SR-STAP for Airborne Radar Based on Meta-Heuristic Algorithms.

The sparse recovery (SR) space-time adaptive processing (STAP) method has excellent clutter suppression performance under the condition of limited observation samples. However, when the cluttering is nonlinear in a spatial-Doppler profile, it will cause an off-grid effect and reduce the sparse recovery performance. A meshless search using a meta-heuristic algorithm (MH) can completely eliminate the off-grid effect in theory. Therefore, genetic algorithm (GA), differential evolution (DE), particle swarm optimization (PSO), and grey wolf optimization (GWO) methods are applied to SR-STAP for selecting exact clutter atoms in this paper. The simulation results show that MH-STAP can estimate the clutter subspace more accurately than the traditional algorithm; PSO-STAP and GWO-STAP showed better clutter suppression performance in four MH-STAP methods. To search for more accurate clutter atoms, PSO and GWO are combined to improve the method's capacity for global optimization. Meanwhile, the fitness function is improved by using prior knowledge of the clutter distribution. The simulation results show that the improved PSO-GWO-STAP algorithm provides excellent clutter suppression performance, which solves the off-grid problem better than does single MH-STAP.

Knockout of Rlim Results in a Sex Ratio Shift toward Males but Superovulation Cannot Compensate for the Reduced Litter Size.

Technologies that can preselect offspring gender hold great promise for improving farm animal productivity and preventing human sex-related hereditary diseases. The maternal Rlim allele is required for imprinted X-chromosome inactivation, which is essential for the normal development of female mouse embryos. In this study, we inactivated the maternal Rlim allele in embryos by crossing a male transgenic mouse line carrying an X-linked CMV-Cre transgene with a female line carrying a loxP-flanked Rlim gene. Knockout of the maternal Rlim gene in embryos resulted in a male-biased sex ratio skew in the offspring. However, it also reduced litter size, and this effect was not compensated for by superovulation in the mother mice. In addition, we showed that siRNA-mediated knockdown of Rlim in mouse embryos leads to the birth of male-only progenies. This study provides a new promising method for male-biased sex selection, which may help to improve the productivity in livestock and prevent sex-associated hereditary diseases in humans.

Identification of the joint line in revision total knee arthroplasty using a multiple linear regression model: a cadaveric study.

INTRODUCTION: The results of revision total knee arthroplasty (rTKA) may be compromised by excessive joint line (JL) elevation. It is critical but challenging in reestablishing the JL in rTKA. Previous studies have confirmed that, biomechanically and clinically, JL elevation should not exceed 4 mm. Image-based studies described several approaches to locate the JL intraoperatively, however magnification errors could occur. In this cadaveric study, we aim to define an accurate and reliable method to determine the JL. MATERIALS AND METHODS: Thirteen male and eleven female cadavers were used, with an average age of death being 48.3 years. The transepicondylar width (TEW), the distance from the medial (MEJL) and lateral (LEJL) epicondyle, adductor tubercle (ATJL), fibular head (FHJL) and tibial tubercle (TTJL) to the JL were measured in 48 knees. Intra- and interobserver reliability and validity were tested prior to any additional analysis. Pearson correlation and linear regression analysis were used to examine the correlations between landmark-JL distances (LEJL, MEJL, ATJL, FHJL and TTJL) and the TEW, and to further derive models for intraoperative JL determination. The accuracy of different models, quantified by errors between estimated and measured landmark-JL distances, was compared using the Friedman and post hoc Dunn tests. RESULTS: The intra- and inter-observer measurements for TEW, MEJL, LEJL, ATJL, TTJL and FHJL did not differ significantly (p > 0.05). Between genders, significant differences were found on TEW, MEJL, LEJL, ATJL, FHJL and TTJL (p < 0.05). There was no association between TEW and either FHJL or TTJL (p > 0.05), while ATJL, MEJL, and LEJL were found to be correlated with TEW (p < 0.05). Six models were derived: (1) MEJL = 0.37*TEW (r = 0.384), (2) LEJL = 0.28*TEW (r = 0.380), (3) ATJL = 0.47*TEW (r = 0.608), (4) MEJL = 0.413*TEW - 4.197 (R2 = 0.473), (5) LEJL = 0.236*TEW + 3.373 (R2 = 0.326), (6) ATJL = 0.455*TEW + 1.440 (R2 = 0.556). Errors were defined as deviations between estimated and actual landmark-JL distances. The mean absolute value of the errors, created by Model 1-6 was 3.18 ± 2.25, 2.53 ± 2.15, 2.64 ± 2.2, 1.85 ± 1.61, 1.60 ± 1.59 and 1.71 ± 1.5, respectively. The error could be limited to 4 mm in 72.9%, 83.3%, 72.9%, 87.5%, 87.5%, and 93.8% of the cases by referencing Model 1-6, respectively. CONCLUSION: Compared to previous image-based measurements, the current cadaveric study most closely resembles a realistic view of intraoperative settings and could circumvents magnification errors. We recommend using Model 6, the JL can be best estimated by referencing the AT and the ATJL can be calculated as ATJL (mm) = 0.455*TEW (mm) + 1.440 (mm).

Multidisciplinary Guidelines for the Rational Use of Topical Non-Steroidal Anti-Inflammatory Drugs for Musculoskeletal Pain (2022).

(1) Background: Topical non-steroidal anti-inflammatory drugs (NSAIDs) are one of the primary drugs for treating musculoskeletal pain. However, there are currently no evidence-based recommendations about drug selection, drug administration, drug interactions, and use in special populations or other pharmacology-related content of such medications. To this end, the Chinese Pharmaceutical Association Hospital Pharmacy Professional Committee developed multidisciplinary guidelines on using topical NSAIDs to treat musculoskeletal pain. (2) Methods: The guidelines development process followed the World Health Organization guideline development handbook, the GRADE methodology, and the statement of Reporting Items for Practice Guidelines in Healthcare. The guideline panel used the Delphi method to identify six clinical questions to be addressed in the guidelines. An independent systematic review team conducted a systematic search and integration of evidence. (3) Results: Based on the balance between the benefits and harms of an intervention, the quality of the evidence, patient preferences and values, and resource utilization, the guideline panel developed 11 recommendations and nine expert consensuses on using topical NSAIDs to treat acute and chronic musculoskeletal pain. (4) Conclusions: Based on the effectiveness and overall safety of topical NSAIDs, we recommend patients with musculoskeletal pain use topical NSAIDs and suggest high-risk patients use topical NSAIDs, such as those with other diseases or receiving other concurrent treatments. The evidenced-based guidelines on topical NSAIDs for musculoskeletal pain incorporated a pharmacist perspective. The guidelines have the potential to facilitate the rational use of topical NSAIDs. The guideline panel will monitor the relevant evidence and update the recommendations accordingly.

Effective Conditions for Achieving Carbon Unlocking Targets for Transport Infrastructure Development-Joint Analysis Based on PLS-SEM and NCA.

It is important to investigate how to achieve carbon unlocking in the transport sector, especially in transport infrastructure, in order to contribute to the achievement of carbon neutrality targets and the 2030 Sustainable Development Goals. This study aims to investigate the necessary and sufficient conditions to achieve carbon unlocking in transport infrastructure. To achieve this, a combination of partial least squares structural equation modeling (PLS-SEM) and necessary condition analysis (NCA) methods have been used to examine whether there are unidentified necessity factors beyond the currently recognized 'technology-in-institution' (TIC) lock-in. This study also explores how the carbon unlocking of transport infrastructure can be achieved through the unlocking of relevant factors. The study includes 366 points from a subjective questionnaire from the government, transport infrastructure researchers, and relevant businesspeople. We found that, at the adequacy level, achieving institutional and technological unlocking is sufficient and economic factors have little impact on transport infrastructure (0.06), and that institutional and technical factors have a large impact on carbon unlocking (0.453, 0.280); however, from the necessary point of view, carbon unlocking at the economic level is necessary to achieve the goal of a medium to high level of carbon unlocking. To achieve carbon unlocking at this level (over 50%), a combination of technological, institutional, and economic factors is required. To achieve full carbon unlocking, the technology, system, and economy need to be at least 0.533, 0.791, and 0.63 unlocked. Therefore, we can conclude that by using the joint analysis of PLS-SEM and NCA, we have achieved an extension of the traditional TIC and identified sufficient and necessary conditions to achieve a medium to high degree of carbon unlocking.

Influencing factors of weak grip strength and fall: a study based on the China Health and Retirement Longitudinal Study (CHARLS).

BACKGROUND: Fall is a major cause of mortality and cause a significant burden on the healthcare system and economic system. Weak grip strength signifies impaired function. Older people with weak grip strength are at a higher risk of death. China has the largest ageing population in the world today. This study aims to analyze the factors contributing to weak grip strength and fall among Chinese. METHODS: This study analyzed data from the 2011 baseline and 2015 follow-up survey of the China Health and Retirement Longitudinal Study (CHARLS). To identify the risk factors of fall and weak grip strength, we used a stepwise multivariable logistic regression model and a least absolute shrinkage and selection operator (LASSO) regression model. RESULTS: In the LASSO regression model, all the risk factors were not shrunken. In the stepwise logistic regression model, adjusted for gender, age, grip strength, depression, and chronic disease, we found that female (aOR = 1.376, 95% CI = 1.243-1.523; P < 0.001), history of ischemic stroke (aOR = 1.786, 95% CI = 1.263-2.524; P = 0.001), depression (aOR = 1.559, 95% CI = 1.396-1.742; P < 0.001), weak grip strength (aOR = 1.285, 95% CI = 1.105-1.494; P = 0.001), older age (aOR = 1.227, 95% CI = 1.163-1.294; P < 0.001), rheumatoid arthritis (aOR = 1.410, 95% CI = 1.270-1.560; P < 0.001), history of kidney disease (aOR = 1.383, 95% CI = 1.136-1.682; P = 0.001) were factors associated with fall significantly. After further adjusting, we found the risk factors of weak grip strength included symptomatic knee osteoarthritis (aOR = 1.755, 95% CI 1.158-2.661; P = 0.008), living in rural area (aOR = 2.056, 95% CI 1.290-3.277; P = 0.002), depression (aOR = 1.523, 95% CI 1.116-2.078; P = 0.008), older age (aOR = 2.116, 95% CI 1.801-2.486; P < 0.001). CONCLUSION: From the study, we found that older age and depression were risk factors of weak grip strength and fall. Weak grip strength was a risk factor of fall. Female, ischemic stroke, kidney disease, rheumatoid arthritis were risk factors of fall; living in rural area and symptomatic knee osteoarthritis were risk factors of weak grip strength.

Influencing factors for the decline of limb muscle strength and the association with all-cause mortality: evidence from a nationwide population-based cohort study.

BACKGROUND: The decline of muscle strength, a typical characteristic of sarcopenia, greatly affects aging-related health outcomes; however, prospective data on influencing factors and mortality in the Chinese population are relatively sparse. AIMS: We investigated the influencing factors for the declined limb muscle strength and the association with all-cause mortality among the elderly Chinese individuals aged ≥ 65 years in a large long-term prospective cohort study. METHODS: We used data from the China Health and Retirement Longitudinal Study (CHARLS). Logistic regression analyses were performed to investigate the influencing factors of declined limb muscle strength. Cox proportional hazard models were used to analyze the impact on all-cause mortality, whose performance was evaluated by train-test cross-validation. RESULTS: The prevalences of declined upper and lower limb strength, which were defined by low hand grip strength (HS) and gait speed (GS), respectively, were 34.4% and 59.7%. The declined HS was significantly associated with older age (p < 0.001), female (p < 0.001), lower educational level (p < 0.001), lower BMI (p < 0.001), and combined with chronic diseases (p = 0.001). Moreover, the declined limb muscle strength was correlated with all-cause mortality (HR: 1.13, 95% CI 1.03-1.21 for HS; HR: 1.09, 95% CI 1.04-1.15 for GS), according to a multi-adjusted model with moderate predictive ability (C-index: 0.714, AUC of 7 year follow-up: 0.716). CONCLUSIONS: The decline of limb muscle strength was prevalent among elderly Chinese individuals and had a strong impact on all-cause mortality. Identification of key populations and tailored interventions on their influencing factors should be implemented in further research.

Incidence and related risk factors of radiographic knee osteoarthritis: a population-based longitudinal study in China.

OBJECTIVE: To explore the incidence and risk factors for radiographic knee osteoarthritis (ROA) in a suburban area of China. METHODS: Shunyi Osteoarthritis Study was a population-based, longitudinal study of knee osteoarthritis in Shunyi, a suburban area of Beijing, China. A total of 1295 residents aged over 50 years were recruited with fully informed by randomized cluster sampling and were followed up 3 years later. At the time of baseline and follow-up visits, participants completed a home interview questionnaire and received a clinical examination including height, weight, range of motion (ROM), chair stand test, 50-foot walk test, and weight-bearing posterior-anterior semi-flexed view of radiographs at tibiofemoral joints. The incident ROA for a knee was defined if its KL grade was no more than grade 1 at baseline visit and no less than grade 2 at the follow-up visit. A patient without ROA in both knees at the baseline visit and with ROA in at least one knee at the follow-up visit was viewed as an incident case of ROA in patient level. Generalized linear model and generalized estimating equation were performed to examine the association between socio-demographic factors, physical function as well as baseline knee joint condition, and incident ROA in patient and knee level. RESULTS: A total of 1295 residents were recruited at baseline in 2014, and 962 (74.3%) residents were followed in 2017. The annual cumulative incidence of ROA was 3.6% at knee level and 5.7% at patient level. Older age (per year, adjusted odds ratio (OR) = 1.079; 95% confidence interval (CI), 1.042-1.117), overweight (adjusted OR = 2.086; 95% CI, 1.286-3.385), female (adjusted OR = 1.756; 95% CI, 1.074-2.877), less ROM (per degree, adjusted OR = 0.952; 95% CI, 0.923-0.983) and Kellgren and Lawrence (KL) grade 1 at baseline (adjusted OR = 8.527; 95% CI, 5.489-13.246) were risk factors for incident ROA. CONCLUSION: The incidence of knee ROA in Chinese suburban area was high. Advanced age, female, overweight, less range of motion, and KL grade 1 at baseline were associated with an increased risk of incident ROA.

The accelerometer-based navigation system demonstrated superior radiological outcomes in restoring mechanical alignment and component sagittal positioning in total knee arthroplasty.

BACKGROUND: This study aimed to determine whether the accelerometer-based navigation (ABN) could improve the accuracy of restoring mechanical axis (MA), component positioning, and clinical outcomes compared to conventional (CON) total knee arthroplasty (TKA). METHODS: A total of 301 consecutive patients (ABN: 27, CON: 274) were included. A 1:4 propensity score matching (PSM) was performed between the two groups according to preoperative demographic and clinical parameters. The postoperative MA, femoral coronal angle (FCA), femoral sagittal angle (FSA), tibial coronal angle (TCA) and tibial sagittal angle (TSA) were compared. Absolute deviations of aforementioned angles were calculated as the absolute value of difference between the exact and ideal value and defined as norms if within 3°, otherwise regarded as outliers. Additional clinical parameters, including the Knee Society knee and function scores (KSKS and KSFS) and range of motion (ROM), were assessed at final follow-up (FU) (mean FU was 21.88 and 21.56 months respectively for ABN and CON group). A secondary subgroup analysis and comparison on clinical outcomes were conducted between norms and outliers in different radiological parameters. RESULTS: A total of 98 patients/102 knees were analyzed after the PSM (ABN: 21 patients/24 knees, CON: 77 patients/78 knees). In the ABN group, the mean MA, FCA and TSA were significantly improved (p = 0.019, 0.006, < 0.001, respectively). Proportions of TKAs within a ± 3°deviation were significantly improved in all the postoperative radiological variables except for TCA (p = 0.003, 0.021, 0.042, 0.013, respectively for MA, FCA, FSA, and TSA). The absolute deviations of FSA and TSA were also significantly lower in the ABN group (p = 0.020, 0.048, respectively). No significant differences were found in either mean value, absolute deviation or outlier ratio of TCA between two groups. On clinical outcomes, there were no significant differences between two groups, although KSKS, KSFS and ROM (p < 0.01, respectively) dramatically improved compared to baseline. The subgroup analysis also demonstrated no statistical difference on clinical outcomes between the outliers and norms in varied radiological parameters. CONCLUSIONS: The ABN could improve the accuracy and precision of mechanical alignment and component positioning without significant improvement of clinical outcomes. Further high quality studies with long term FU are warranted to comprehensively evaluate the value of the ABN.

Patellofemoral arthroplasty versus total knee arthroplasty for isolated patellofemoral osteoarthritis: a systematic review and meta-analysis.

BACKGROUND: Isolated patellofemoral osteoarthritis (PF-OA) is a common subtype of knee osteoarthritis, leading to a huge economic burden on health care systems. Although previous studies have shown that patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA) have good clinical effects, it remains largely unclear which treatment is more effective for patients with isolated PF-OA. We aimed to compare postoperative function, complications, revision rates, level of physical activity, and satisfaction rate between the two surgical techniques. METHODS: Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Search of literature was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until November 2020. The included studies were those that provided direct comparison of postoperative outcomes between PFA and TKA. Data were extracted from eligible studies and combined to calculate the pooled odds ratio (OR) and 95% confidence interval (CI). Sensitivity analysis and subgroup analysis were conducted to evaluate heterogeneity between the two groups. RESULTS: A total of 7 eligible studies (3 recent randomized controlled trials and 4 nonrandomized controlled trials) were included in this meta-analysis. The pooled results showed that both the PFA group and the TKA group had improved postoperative indicators, suggesting that the two operation modes could improve the knee function and quality of life of patients. Throughout the first 2 years postoperatively, higher activity level, and better functional recovery were observed for PFA compared with TKA in this study; moreover, the differences between the two operation modes were statistically significant (p < 0.05). We found no significant difference in complications, revision rates, and satisfaction rate between the two procedures. CONCLUSION: Although there was no observed difference in the complications, revision rates, and satisfaction rate between PFA and TKA, PFA was superior to TKA in terms of knee function and physical activity in the first 2 years postoperatively. Therefore, PFA is a safe, effective, and less invasive treatment for patients with isolated PF-OA. Our findings are consistent with the systematic review of current evidence that PFA may be more suitable for younger patients with high activity needs. Patient selection is, therefore, thought to be of paramount importance. Individualized surgical plan should be designed according to the patient's age, BMI, KOA site, and activity level and combined with the doctor's personal experience.

Depicting developing trend and core knowledge of hip fracture research: a bibliometric and visualised analysis.

BACKGROUND: Hip fracture is common and carries high morbidity and mortality; thus, it has become a vital concern. We aim to analyse the present status, worldwide trends in hip fracture and state of clinical research. METHODS: Publications from 2000 to 2019 were retrieved from the Web of Science database and analysed using a bibliometric methodology. VOSviewer software was utilised for analysis. RESULTS: In total, 6139 publications were included, and publications increased annually from 152 in 2000 to 592 in 2019. U.S. researchers have produced the most publications, the highest H-index and the greatest number of citations. Osteoporosis International has published the most papers on the topic. Leading researchers, contributing institutions, their cooperative relationships and scientific masterpieces have been identified. The publications can be divided into five clusters: 'mortality', 'surgical management', 'rehabilitation', 'osteoporosis' and 'epidemiology'. A clear developing trend was described, which began with fracture epidemiology and prevention, transitioned to perioperative management, orthogeriatric care and patient safety and then to functional recovery, disease burden and national audits in recent times. CONCLUSIONS: Hip fractures result in conditions that extend far beyond orthopaedics concerning epidemiology and preventive medicine, internal medicine and endocrinology, as well as critical care and gerontology. Interest, research and publications are on the rise.

Complexity Changes in the US and China's Stock Markets: Differences, Causes, and Wider Social Implications.

How different are the emerging and the well-developed stock markets in terms of efficiency? To gain insights into this question, we compared an important emerging market, the Chinese stock market, and the largest and the most developed market, the US stock market. Specifically, we computed the Lempel-Ziv complexity (LZ) and the permutation entropy (PE) from two composite stock indices, the Shanghai stock exchange composite index (SSE) and the Dow Jones industrial average (DJIA), for both low-frequency (daily) and high-frequency (minute-to-minute)stock index data. We found that the US market is basically fully random and consistent with efficient market hypothesis (EMH), irrespective of whether low- or high-frequency stock index data are used. The Chinese market is also largely consistent with the EMH when low-frequency data are used. However, a completely different picture emerges when the high-frequency stock index data are used, irrespective of whether the LZ or PE is computed. In particular, the PE decreases substantially in two significant time windows, each encompassing a rapid market rise and then a few gigantic stock crashes. To gain further insights into the causes of the difference in the complexity changes in the two markets, we computed the Hurst parameter H from the high-frequency stock index data of the two markets and examined their temporal variations. We found that in stark contrast with the US market, whose H is always close to 1/2, which indicates fully random behavior, for the Chinese market, H deviates from 1/2 significantly for time scales up to about 10 min within a day, and varies systemically similar to the PE for time scales from about 10 min to a day. This opens the door for large-scale collective behavior to occur in the Chinese market, including herding behavior and large-scale manipulation as a result of inside information.

The role of knee arthroscopy in managing common soft tissue complications after total knee arthroplasty: a retrospective case series study.

BACKGROUND: To investigate the feasibility, safety and therapeutic efficacy of arthroscopy in managing the 3 most common soft tissue complications, peripatellar impingement (PI), arthrofibrosis (AF) and generalized synovitis (GS), after total knee arthroplasty (TKA). METHODS: A retrospective review of patients undertaking arthroscopy for PI, AF and GS was conducted. Outcome measures included complications, postoperative range of motion (ROM), Knee Society Score (KSS) and rates of symptom recurrence, prosthesis revision. Intraoperative findings and surgical procedures were also recorded. Paired t test, Fisher's exact test, Kruskal-Wallis test and post hoc analysis with Bonferroni correction were used for statistical evaluation. RESULTS: A total of 74 patients, including 35 patients with peripatellar impingement, 25 patients with arthrofibrosis and 14 patients with generalized synovitis, with a mean age of 66.1 ± 7.9 years, were analysed. The mean follow-up (FU) duration was 81.3 ± 40.6 months. All patients underwent arthroscopic surgery safely without intraoperative complications. However, there were 4 postoperative complications, including 1 acute myocardial infarction and 3 periprosthetic joint infections. Overall, patients acquired improvements in ROM from 81.7 ± 23.1° to 96.8 ± 20.5° (p < 0.05), in KSS knee score from 64.2 ± 9.6 to 78.7 ± 12.1 (p < 0.05) and in KSS function score from 61.1 ± 7.4 to 77.3 ± 12.2 (p < 0.05) postoperatively. Patients in all 3 groups had improvements in ROM (p < 0.05), KSS knee score (p < 0.05) and KSS function score (p < 0.05). The overall recurrence rate was 22.9% (95% confidence interval (CI) 15.1-34.9%), and the overall revision rate was 14.9% (95% CI 8.6-25.6%). There were significant differences in both the symptom recurrence and prosthesis revision rates among the groups (p < 0.05). The PI group had a significantly lower symptom recurrence rate (11.4%, 95% CI 4.5-28.7%) and revision rate (8.6%, 95% CI 2.9-25.3%) (p < 0.017), while the GS group had a significantly higher recurrence rate (42.9%, 95% CI 23.4-78.5%) and revision rate (35.7%, 95% CI 17.6-72.1%) (p < 0.017). CONCLUSIONS: In the setting of symptomatic TKA, although carrying certain risks for PJI and other complications, arthroscopic intervention could be feasible and provide clinical improvement in most cases at an average of 81.3 months follow-up. Patients with PI had the best outcomes, while patients with GS had the worst outcomes. LEVEL OF EVIDENCE: Level IV.

The prevalence and economic burden of pain on middle-aged and elderly Chinese people: results from the China health and retirement longitudinal study.

BACKGROUND: To estimate the prevalence of pain among people aged 45 years and older in China, to analyze the effect factors of pain and pain related economic burden. METHODS: Nationally representative sample was derived from China Health and Retirement Longitudinal Study (CHARLS). Pain data, medical cost data were obtained, as well as information of demographic characteristics, social structure, social-economic status, other health needs and health behaviors. The prevalence of pain in 2011, 2013, and 2015 was calculated. Univariate analysis and multivariate analysis were used to find the effect factors of pain. An optimization two-part model was used to calculate the range of the direct medical costs caused by pain. RESULTS: The prevalence of pain among people 45 years or older in China was 31.73% in 2011, 37.27% in 2013 and 28.62% in 2015. When evaluating factors lead a higher prevalence of pain, the results of the multi-variable after one-way analysis were older age, female, lower education, rural residents, without insurance status, abstained from alcohol and lower body mass index (BMI). Through the optimization of two-part model, the direct medical costs caused by pain was 898.9-1563.0 yuan in 2011, 2035.8-2568.7 yuan in 2013 and 2628.8-3945.7 yuan in 2015 (129.9US$ - 225.9US$ in 2011, 294.2 US$ - 371.2US$ in 2013 and 379.9US$ - 570.2US$ in 2015, converted to 2010 RMB). CONCLUSION: The prevalence of pain among middle-aged and elderly Chinese is high. Residents with older age, female, lower education, rural residents, without insurance status, abstained from alcohol and lower BMI seem to have a higher pain prevalence. Pain can cause extra direct medical costs and will cause more economic loss with the progress of time. Future research should pay more attention to effective treatment, management and prevention of pain to decrease its burden.

Burden of osteoarthritis in China, 1990-2017: findings from the Global Burden of Disease Study 2017.

BACKGROUND: China has seen a remarkable epidemiological and demographic transition during the past three decades. We aimed to describe the prevalence of osteoarthritis as well as years lived with disability (YLDs) due to osteoarthritis in China, according to age, sex, and geographical location, from 1990 to 2017. METHODS: Data were obtained from systematic reviews of symptomatic osteoarthritis of the knee and hip in the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017). Three categories of sequelae (mild, moderate, and severe) of osteoarthritis were defined to indicate the degrees of severity and functional loss associated with the condition. A Bayesian meta-regression tool was applied to estimate the prevalence of osteoarthritis and the distribution of its severity. YLDs were calculated by multiplying the prevalence of osteoarthritis sequelae by their corresponding disability weights. All data were analysed by age-sex-province-year groups in China. FINDINGS: Around 26·1 million individuals in China had osteoarthritis in 1990, and this number rose to 61·2 million in 2017. The age-standardised prevalence of osteoarthritis increased from 2·9% (95% uncertainty interval 2·5-3·3) in 1990 to 3·1% (2·7-3·4) in 2017. The total YLDs due to osteoarthritis increased from 0·84 million (0·42-1·69) in 1990 to 1·97 million (0·98-3·94) in 2017, while the age-standardised YLD rate increased from 92·5 (45·7-185·6) per 100 000 people to 98·8 (49·4-197·6) per 100 000. Osteoarthritis prevalence and YLDs were higher in females than in males, and YLD rate increased with age. Osteoarthritis was the 24th most common cause of YLDs in China in 2017, accounting for 1·08% (0·64-2·02) of all YLDs. INTERPRETATION: Osteoarthritis is prevalent in China. Between 1990 and 2017, disease burden increased and varied greatly according to geographical location. Appropriate prevention and treatment strategies, predominantly those targeted at women, older people, and underdeveloped areas, must be developed to reduce the burden of the disease. FUNDING: National Natural Science Foundation of China, China National Key Research and Development Programme.

Severe Wear and multiple Pseudotumor formation due to revision for ceramic head breakage after ceramic-on-ceramic Total hip arthroplasty: a case report.

BACKGROUND: Head breakage is a serious complication following total hip arthroplasty when using Ceramic on Ceramic bearings surfaces. There is still in controversy about the selection of bearing surfaces when conducting revision surgery. CASE PRESENTATION: We describe the case of a fifty-year-old man who had undergone right total hip arthroplasty (THA) with ceramic-on-ceramic prostheses in 2011. After a fall 6 years after the primary procedures, radiographs suggested a ceramic head breakage for revision THA with exchange of metal-on-polyethylene bearing. However, 8 months later, severe metallosis and multiple pseudotumor was confirmed in pelvis and surrounding hip after re-revision THA with ceramic-on-polyethylene prostheses. Analysis of the serum metal ion indicated massive wear of the metal head and erosion of the stem neck and taper. CONCLUSIONS: This case vividly demonstrates metal bearings should be avoided and revision with complete synovectomy and thorough debridement should be performed whenever possible for a fractured ceramic bearing.

Efficacy and potential determinants of exercise therapy in knee and hip osteoarthritis: A systematic review and meta-analysis.

BACKGROUND: Exercise is an effective treatment for osteoarthritis. However, the effect may vary from one patient (or study) to another. OBJECTIVE: To evaluate the efficacy of exercise and its potential determinants for pain, function, performance, and quality of life (QoL) in knee and hip osteoarthritis (OA). METHODS: We searched 9 electronic databases (AMED, CENTRAL, CINAHL, EMBASE, MEDLINE Ovid, PEDro, PubMed, SPORTDiscus and Google Scholar) for reports of randomised controlled trials (RCTs) comparing exercise-only interventions with usual care. The search was performed from inception up to December 2017 with no language restriction. The effect size (ES), with its 95% confidence interval (CI), was calculated on the basis of between-group standardised mean differences. The primary endpoint was at or nearest to 8 weeks. Other outcome time points were grouped into intervals, from<1 month to≥18 months, for time-dependent effects analysis. Potential determinants were explored by subgroup analyses. Level of significance was set at P≤0.10. RESULTS: Data from 77 RCTs (6472 participants) confirmed statistically significant exercise benefits for pain (ES 0.56, 95% CI 0.44-0.68), function (0.50, 0.38-0.63), performance (0.46, 0.35-0.57), and QoL (0.21, 0.11-0.31) at or nearest to 8 weeks. Across all outcomes, the effects appeared to peak around 2 months and then gradually decreased and became no better than usual care after 9 months. Better pain relief was reported by trials investigating participants who were younger (mean age<60 years), had knee OA, and were not awaiting joint replacement surgery. CONCLUSIONS: Exercise significantly reduces pain and improves function, performance and QoL in people with knee and hip OA as compared with usual care at 8 weeks. The effects are maximal around 2 months and thereafter slowly diminish, being no better than usual care at 9 to 18 months. Participants with younger age, knee OA and not awaiting joint replacement may benefit more from exercise therapy. These potential determinants, identified by study-level analyses, may have implied ecological bias and need to be confirmed with individual patient data.