[Effect of changes in posterior tibial slope on the mid-term clinical outcomes of Oxford unicompartmental knee arthroplasty].

Objective: To investigate the impact of changes in the posterior tibial slope (PTS) in Oxford unicompartmental knee arthroplasty (OUKA) on the mid-term clinical outcomes of postoperative patients. Methods: This study was a follow-up study. The data of 135 patients (150 knees) who underwent OUKA at the China-Japan Friendship Hospital from January 2012 to January 2013 were analyzed retrospectively. The patients were followed-up for at least ten years. According to the changes in PTS of the medial tibial plateau before and after surgery, patients were divided into three groups: group A (PTS decreased by more than 5°), group B (PTS changed by 5° or less), and group C (PTS increased by more than 5°). The Knee Society Clinical Score (KSS-C), Knee Society Functional Score (KSS-F), Oxford Knee Score (OKS), Forgotten Joint Score (FJS), and knee range of motion (ROM) among the three groups were compared at the last follow-up. Results: Prior to the final follow-up assessment, six patients expired, and an additional nine patients were lost to follow-up. A total of 120 patients (135 knees) were enrolled in this study (30 males and 90 females). The mean age was (66.29±8.62) years, and the follow-up time was (10.54±0.72) years. Group A consisted of 32 patients (34 knees), group B comprised 77 patients (90 knees), and group C included 11 patients (11 knees). One knee in group A suffered prosthesis loosening, and two knees in group C experienced postoperative bearing dislocation, one knee encountered bearing fragmentation. The incidence of postoperative complications differed significantly among the three groups (P<0.05). The preoperative OKS was (33.91±6.59) points, KSS-F was (43.46±8.99) points, KSS-C was (41.05±5.70) points and ROM was 115.23°±13.53°; after the surgery, they changed to (18.82±7.01) points, (81.51±7.34) points, (82.64±7.94) points, and 119.07°±8.62°, respectively, and all the differences were statistically significant (all P<0.001). In terms of postoperative outcomes, group A had an OKS of (21.44±8.46) points and a FJS of (63.83±11.40) points, group B had an OKS of (17.07±5.81) points and a FJS of (70.49±12.45) points, group C had an OKS of (25.09±5.07) points and a FJS score of (59.48±10.09) points; the differences among the three groups were all statistically significant (all P<0.05), but there were no significant differences in the postoperative KSS scores and ROM among the three groups (all P>0.05). Conclusions: After OUKA, better mid-term clinical outcomes are achieved when ΔPTS is<5°. Although the recommended central value for PTS in OUKA is 7° according to Oxford, it should be individualized, and it is recommended to consider the preoperative angle, with a change of less than 5° before and after surgery.

[Clinical results of medial mobile bearing unicompartmental knee arthroplasty using kinematic alignment technique with at least 5-years follow-up].

Objective: To evaluate the mid-term results of kinematic alignment technique in Oxford mobile bearing unicompartmental knee arthroplasty (OUKA). Methods: The clinical data of first 98 knees OUKA performed from June 2015 to January 2017 using kinematic alignment technique with at least 5-year follow-up were retrospectively analyzed, including 28 knees in 24 males and 70 knees in 62 females. The mean surgical age was (68.4±8.0) years. The clinical data of patients before operation and at the last follow-up were recorded and compared. The knee Hospital for Special Surgery (HSS) score, visual analogue scale (VAS) of pain, range of motion, surgical complications and radiological assessment were analyzed to evaluate the efficacy of kinematic alignment technique in OUKA. Results: The mean follow-up was (70.9±5.9) months (60-81 months). The mean operation time was (56.4±9.1) minutes. There was no conversion to total knee replacement, no collateral ligament injury and no fracture in operation. The postoperative hospital stay was (5.8±1.9) days. Postoperative hemoglobin drop was (12.7±5.5) g/L. There was no blood transfusion. No patient died during perioperative period. No serious adverse events related to surgery occurred after operation, such as pulmonary embolism, fat embolism, cardio-cerebrovascular accident, etc. No revision, bearing dislocation, periprosthetic joint infection, prosthesis aseptic loosening, contralateral compartment arthritis progression occurred at final follow-up. Three patients reported persistent unexplained knee pain. Afther the operation, the HSS score increased from 59.1±8.2 to 91.8±5.6 after the operation, the range of motion increased from 122.4°±10.0° to 125.6°±7.1°, and the VAS score decreased from 6.9±0.8 to 1.6±1.2 (all P<0.05). Radiological assessment showed that 92.9%(91/98) implant positions were ideal and 7 knees were outliers. The mean HKAA was 173.3°±3.7° before surgery and it was 177.2°±3.0° after surgery (P=0.038). The mean A angle of femur varus/valgus angle was 2.0°±2.8° (-11°-13°), and the mean B angle of femur flexion/extension angle was 4.8°±3.4°(0°-17°). The mean tibia valgus/valgus angle E angle was 1.0°±1.9°(-4°-9°), and the mean F angle was 6.7°±2.3°(1°-12°). The mean postoperative prosthesis distance was (4.29±2.46)mm(2-7 mm). Conclusions: It's demonstrated that the kinematic alignment technique follows the design principle of OUKA, has satisfactory mid-term results. The radiological assessment of the prosthesis is acceptable.

[Correlational between the gap contact force and the degree of lower limb alignment correction in Oxford mobile bearing unicompartmental knee arthroplasty].

Objective: To study the correlation between joint contact force and postoperative lower extremity alignment in Oxford unicompartmental knee arthroplasty (OUKA) and provide reference data for predicting the lower extremity alignment after OUKA. Methods: It was a retrospective case series study. A total of 78 patients (92 knees) who underwent OUKA surgery from January 2020 to January 2022 in the Department of Orthopedics and Joint Surgery of China-Japan Friendship Hospital were included in this study, including 29 males and 49 females, aged (68.8±6.9) years. A custom-designed force sensor was used to measure gap contact force in the medial gap of OUKA. The patients were divided into groups according to the varus degree of lower limb alignment after operation. Relationship between the gap contact force and the alignment of the lower limbs after operation was analyzed with Pearson correlation analysis, and the gap contact force was compared between patients with different lower limbs alignment correcting results. Results: The mean contact force measured during the operation at 0° of knee extension was 81.7 N±57.8 N, and it was 96.1 N±54.5 N at 20° of knee flexion. The average postoperative knee varus angle was 2.9°±2.7°. The gap contact force at the 0° and 20° positions of the knee joint was negatively correlated with the varus degree of the postoperative lower limb alignment (r=-0.493, -0.331, both P<0.001). The distribution of gap contact force at 0° was different in each group, the contact force [M (Q1, Q3)] of the neutral position group(n=24) was 117.4 N (31.7 N, 233.0 N), and it was 63.7 N (11.3 N, 209.0 N), 31.5 N (8.3 N, 87.7 N) in the mild varus group (n=51) and the significant varus group (n=17), respectively, and the difference was statistically significant (P<0.001); while at 20°, only the difference between the significant varus group and the neutral position group was statistically significant (P=0.040). The gap contact force of the alignment satisfactory group at 0° and 20° was greater than those in the significant varus group (both P<0.05). The gap contact force measured at 0° and 20° was significantly greater in patients with preoperative significant flexion deformity than in patients without flexion deformity (or mild flexion deformity) (both P<0.05). Conclusions: OUKA gap contact force is related to the degree of lower limb alignment correction after the operation. In patients with well-corrected lower limb alignment after surgery, the median intraoperative knee joint gap contact force at 0° and 20° is 117.4 N and 92.5 N, respectively.

[The epidemiology and pathogeny investigation of two clusters of severe fever with thrombocytopenia syndrome disease outbreaking in Henan Province, 2022].

To investigate two clusters of severe fever with thrombocytopenia syndrome virus (SFTSV) in Xinyang City, Henan Province, in 2022, and analyze their causes, transmission route, risk factors, and the characteristics of virus genetic variation. Case search and case investigation were carried out according to the case definition. Blood samples from cases, family members and neighbors and samples of biological vectors were collected for RT-PCR to detect SFTSV. The whole genome sequencing and bioinformatics analysis were performed on the collected positive samples. A total of two clustered outbreaks occurred, involving two initial cases and ten secondary cases, all of which were family recurrent cases. Among them, nine secondary cases had close contact with the blood of the initial case, and it was determined that close contact with blood was the main risk factor for the two clustered outbreaks. After genome sequencing analysis, we found that the SFTSV genotype in two cases was type A, which was closely related to previous endemic strains in Xinyang. The nucleotide sequence of the SFTSV in the case was highly homologous, with a total of nine amino acid mutation sites in the coding region. It was not ruled out that its mutation sites might have an impact on the outbreak of the epidemic.

[The association of posterior tibial slope changes between joint gap contact force and the range of motion in Oxford mobile bearing unicompartmental knee arthroplasty].

Objective: To investigate the correlation between the change of posterior tibial slope (PTS) after unicompartmental knee arthroplasty (UKA) and the contact force at the end stage of knee flexion and extension, as well as the postoperative range of motion. Methods: The data of 38 cases (46 knees) of UKAs undertaken in China-Japan Friendship Hospital from June 2020 to June 2021 were analyzed in this study. A custom-designed force sensor was used to measure gap contact force in the medial gap of UKA. The correlations between each two of the three factors-the change of PTS (∆PTS), the gap contact force of full extension and deep flexion and the range of knee motion were analyzed. Results: Totally of 38 patients (46 knees) were enrolled, including 14 males and 24 females, aged (69.1±7.4) years, with an average follow-up of (11.2±3.7) months. The average gap contact force was (88.3±40.6)N, the adjusted contact force of the full extension gap was 81.7%±33.8%, while that of the deep flexion gap was 55.6%±31.0%. At the last follow-up, the fixed flexion degree[M(Q1, Q3)] was 0°(0°, 3°), which was significantly lower than the preoperative value of 0°(0°, 5°) (P<0.05); the postoperative max flexion degree was 115.9°±16.4°, it was increased when compared with the preoperative value of 112.0°±16.8° (P<0.05); and the postoperative PTS was 8.3°±2.7°, and there was no significant difference with the preoperative value (8.6°±2.1°,P>0.05). There was a positive correlation between ∆PTS and both the contact force of full extension gap and the fixed flexion degree (r=0.334 and 0.317, P<0.05). Besides, there was a negative correlation between ∆PTS and the contact force of the deep flexion gap (r=-0.397, P<0.05). However, the correlations between these two factors and the max flexion degree were not significant (P>0.05). Conclusions: The reduction of PTS in UKA would reduce the contact force of the full extension gap, as well as the postoperative fixed flexion deformity. Besides, it could increase the contact force of the deep flexion gap, but would not influence the max flexion degree of the knee postoperatively.

[Analysis of the whole genome traceability and transmission path simulation experiment of the local cluster COVID-19 epidemic].

Objective: To trace and characterize the whole genome of SARS-CoV-2 of confirmed cases in the outbreak of COVID-19 on July 31, 2021 in Henan Province. Method: Genome-wide sequencing and comparative analysis were performed on positive nucleic acid samples of SARS-CoV-2 from 167 local cases related to the epidemic on July 31, 2021, to analyze the consistency and evolution of the whole genome sequence of virus. Results: Through high-throughput sequencing, a total of 106 cases of SARS-CoV-2 whole genome sequences were obtained. The results of genome analysis showed that the whole genome sequences of 106 cases belonged to the VOC/Delta variant strain (B.1.617.2 clade), and the whole genome sequences of 106 cases were shared with the genomes of 3 imported cases from Myanmar admitted to a hospital in Zhengzhou. On the basis of 45 nucleotide sites, 1-5 nucleotide variation sites were added, and the genome sequence was highly homologous. Conclusion: Combined with the comprehensive analysis of viral genomics, transmission path simulation experiments and epidemiology, it is determined that the local new epidemic in Henan Province is caused by imported cases in the nosocomial area, and the spillover has caused localized infection in the community. At the same time, it spills over to some provincial cities and results in localized clustered epidemics.

Severe fever with thrombocytopenia syndrome virus: a systematic review and meta-analysis of transmission mode.

Severe fever with thrombocytopenia syndrome (SFTS) is a disease with a high case-fatality rate that is caused by infection with the SFTS virus (SFTSV). Five electronic databases were systematically searched to identify relevant articles published from 1 January 2011 to 1 December 2019. The pooled rates with 95% confidence interval (CI) were calculated by a fixed-effect or random-effect model analysis. The results showed that 92 articles were included in this meta-analysis. For the confirmed SFTS cases, the case-fatality rate was 0.15 (95% CI 0.11, 0.18). Two hundred and ninety-six of 1384 SFTS patients indicated that they had been bitten by ticks and the biting rate was 0.21 (95% CI 0.16, 0.26). The overall pooled seroprevalence of SFTSV antibodies among the healthy population was 0.04 (95% CI 0.03, 0.05). For the overall seroprevalence of SFTSV in animals, the seroprevalence of SFTSV was 0.25 (95% CI 0.20, 0.29). The infection rate of SFTSV in ticks was 0.08 (95% CI 0.05, 0.11). In conclusion, ticks can serve as transmitting vectors of SFTSVs and reservoir hosts. Animals can be infected by tick bites, and as a reservoir host, SFTSV circulates continuously between animals and ticks in nature. Humans are infected by tick bites and direct contact with patient secretions.

A critical review on life cycle assessment and plant-wide models towards emission control strategies for greenhouse gas from wastewater treatment plants.

For decades, there has been a strong interest in mitigating greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs). Numerous models were developed to measure the emissions and propose the quantification. Existing studies looked at the relationship between GHG emissions and operational cost (OCI), which is one of the most important indicators for decision-makers. Other parameters that can influence the control strategies include the effluent quality (EQI) and total environmental impacts. Plant-wide models are reliable methods to examine the OCI, EQI and GHG emissions while Life cycle assessment (LCA) works to assess the potential environmental impacts. A combined LCA and plant-wide model proved to be a valuable tool evaluating and comparing strategies for the best performance of WWTPs. For this study involving a WWTP, the benchmark model is used while LCA is the decision tool to find the most suitable treatment strategy. LCA adds extra criteria that complement the existing criteria provided by such models. Complementing the cost/performance criteria is proposed for plant-wide models, including environmental evaluation, based on LCA, which provides an overall better assessment of WWTPs. It can capture both the dynamic effects and potential environmental impacts. This study provides an overview of the integration between plant-wide models and LCA.

[Role and controversy of unicompartmental knee arthroplasty in treatment of knee osteoarthritis].

A stepwise algorithm was proposed for the management of knee osteoarthritis.Unicompartmental knee arthroplasty(UKA) is a promising treatment option for unicompartmental knee osteoarthritis and widely used.It just replaces the lesion compartment with many advantages such as a smaller incision, less soft tissue injury, and more rapid recovery.UKA restores the native knee kinematics as the other compartments and knee ligaments are largely retained.Although there were many evidences that UKA could achieve good results when patient selections and surgical techniques were accurate.However, some registry data reported that UKA prostheses had lower survival rates compared to total knee arthroplasty.In this review, we try to analyze the current controversies, and evaluate the status and role for UKA in the treatment of knee osteoarthritis.Good results for knee osteoarthritis could be achieved by selecting appropriate methods and using UKA correctly in the future.

[Efficacy and safety of compound betamethasone cocktail therapy in primary unilateral unicompartmental knee arthroplasty].

Objective: To evaluate the efficacy and safety of an intraoperative betamethasone periarticular injection in patients undergoing primary unicompartmental knee arthroplasty (UKA). Methods: Seventy patients with knee anteromedial osteoarthritis who underwent the primary unilateral UKA in China-Japan Friendship Hospital from July 2017 to October 2018 were randomized into two groups with random number table. In the group A, an analgesic mixture of morphine, ropivacaine, epinephrine, ketorolac and betamethasone was infiltrated intraoperatively into the soft tissue. While in the group B, a same volume of mixture without betamethasone was injected alternatively. The visual analogue scale (VAS) of pain and analgesic consumption were evaluated to compare the effectiveness of pain control between the two groups. In addition, maximal flexion of the knee andinitial time of the straight leg raising were monitored. Complications were assessed too. The data were compared with independent-sample t test. Results: No significant differences in VAS score was found between the groups at 6 h and 12 h after the operation (t=-1.154, -1.108, both P>0.05), but the pain level and analgesic consumption were significantly lower in the group A from 18 h to 72 h post operation (t=-2.959, -2.808, -2.080, -2.519, -3.378, -3.237, all P<0.05). The maximal flexion in group A was significantly higher than that in the group B from 1 d to 3 d (t=2.985, 4.575, 4.013, all P<0.05). The straight leg raising ability and incidence of complications were similar between the groups (χ(2)=0.141, 0.000, both P>0.05). Conclusions: The cocktail analgesics injection containing small dose of betamethasone during UKA can provide effective acute pain control early after the surgery, which is conducive to knee joint function, and it does not increase the incidence of postoperative complications.

[Microbiology analysis of periprothetic joint infection post total hip and knee arthroplasty of 9 centers in Beijing between 2014 and 2016].

Objective: To investigate the microbiological test, antibiotic sensitivity and surgical treatment of periprosthetic joint infection(PJI) cases in post total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients. Methods: A retrospective cross-sectional survey was conducted on 318 patients who underwent THA or TKA in 9 clinical centers in Beijing from January 2014 to December 2016.The data of microbiology, antibiotic sensitivity and surgical treatment were collected.The average age of patients was (62.3±13.1) years old (range: 21-86 years old), including 145 males and 173 females.The body mass index was (25.6±3.8) kg/m (2) (range: 15.6-38.1 kg/m(2)). Results: In total, 318 patients had microorganisms detected by periprosthetic tissue culture or synovial fluid culture, 209 cases (65.7%) had Gram-positive bacteria, 29 cases (9.1%) had Gram-negative bacteria, 10 cases (3.1%) had fungi, 3 cases (0.9%) had non-tuberculous mycobacteria, 72 cases (22.6%) were negative, 69 cases (21.7%) had methicillin-resistant bacteria. The antibiotic sensitivity results showed that the overall resistance rate of penicillin, cefuroxime, amoxicillin+clavulanic acid was 79.9%, 69.9%, and 68.1%, respectively; meropenem, vancomycin, and linezolid resistance rate was 0. For the treatment methods of hip and knee PJI, two-stage revision surgery acounted for 72.9% (108/148) and 64.1% (109/170), respectively. One-stage revision surgery accounted for 21.6% (32/148) and 7.6% (13/170), and open debridement surgery accounted for 4.7%(7/148) and 26.4% (45/170). Conclusions: Gram-positive bacteria was still the main pathogen of PJI.The methicillin-resistant bacteria and rare bacteria should be payed attention to. The Majority of hip and knee PJI cases were treated by two-stage revision surgery.

[Individual difference of coronal bowing of femur and its influence on the lower limbs alignment after the total knee arthroplasty].

Objective: To disclose the correlation between the femur bowing angle(FBA) and vulgas correction angle(VCA), anlysys its influence on the total knee arthroplasty and the lower limbs alignment. Methods: From Janurary 2013 to December 2015, 699 patients who had received total knee arthroplasty(TKA)were collected in the Department of Joint Surgery, China-Japan Friendship. The FBA, VCA, offset of the proximal femur, the lengh of the femur, the neck shaft angle of the femur of the eligible cases from the long leg X-ray were measured.All the data were analysed for the following steps: the FBA's mean value and characteristics of distributation of all the cases; the VCA's mean value and characteristics of distributation of all the cases; correlations between the VCA and the other parameters; divide all the cases into four groups based on the value of FBA : group A(FBA<-3°, 29), group B(-3°≤FBA≤0°, 255), group C(0°3°, 236)and then plan to cut the distal femur with 5° and 6°, respectively. The percent of ideal alignmental outcome's percentage of every group were compared. Results: The mean Value of the FBA is -7.1--12.1(1.4±2.4)°; the mean Value of the VCA is 2.5--11.9(6.5±1.3)°. The correlation index between VCA and FBA, the neck shaft angle of the femur , offset of the hip joint, the lengh of the femur is 0.72, -0.26, 0.45 and -0.08, perspectively. The theoretical ideal alignment percentage of the 5 degree-valgus-bone cut and 6 degree-valgus-bone cut in every group is group A: 89.7% and 66.5%; group B: 93.7% and 95.7%; group C: 71.9% and 94.6%; group D: 21.2% and 50.8%, respectively. Conclusion: The cases whose femur bowing angles are outliers are common in daily medical practice, so the vulgas correction angles need be ajusted for its significant correlation with FBA. 5 degree-valgus-bone cut or 6 degree-valgus-bone cut could not get the ideal alignment some times.

[Influence of tibial component slope on short-term clinical outcome for Oxford unicompartmental knee arthroplasty].

Objective: To investigate the effects of tibial component slope change after microplasty (MP) Oxford unicompartmental knee arthroplasty (UKA) on short-term clinical outcome. Methods: A total of 116 patients(128 UKAs)underwent UKA in Department of Orthopaedic Surgery of China-Japan Friendship Hospital between January 2014 and December 2015 were retrospectively reviewed. Totally 100 patients (108 UKAs) were finally included in the study. There were 31 males and 69 females, aging from 47 to 90 years (mean 67.2 years). The mean height was (161.9±8.4) cm and the mean body mass index (BMI) was (26.2±3.3) kg/m(2). The posterior tibial slope (PTS) at preoperative and postoperative were measured on the lateral radiograph. The postoperative PTS were divided into five groups (<3°, 3° to 5°, 5° to 7°, 7° to 9° and>9°). The Oxford Knee Score (OKS) was recorded. Pearson correlation analysis, ANOVA and t test were used to analyze data. Results: All operations were successfully accomplished and there were no transfusion, infection, thrombus and other complications. There was 1 patient accepted revision because of bearing dislocation. Compared to preoperative, the PTS decreased (6.5°±2.2° vs.9.6°±3.4°) postoperative, there was statistical difference (t=9.053, P<0.01). Only 3 patients were beyond the recommended range (2° to 12°). A total of 82 patients (86 UKAs) were followed up. The follow-up time was 1 to 2.9 years (mean 2 years). The OKS was 43.0±4.1 (mean 31 to 48). The PTS increased in 12 patients (12 UKAs) postoperative, the mean OKS was 40.5±5.2. The PTS decreased in 70 patients (74 UKAs), the mean OKS was 43.4±3.8. There were significant difference in OKS (t=2.347, P=0.021). There were no significant difference in OKS between the five groups. There were positive correlation between postoperative PTS and preoperative PTS (r=0.201, 95%CI: 0.001 to 0.396, P=0.037), there were no correlations between postoperative PTS and hight and BMI. There were negative correlations between OKS and postoperative PTS (r=-0.255, 95%CI: -0.063 to -0.427, P=0.018) and PTS change (r=-0.292, 95%CI: -0.08 to -0.475, P<0.01). Conclusions: Satisfying PTS can be obtained by use of Oxford MP instrumentation. The clinical outcome of the postoperative PTS decreased was relatively better. Too large posterior slope of the tibial implant should be avoided.

[Effect of icariin on the proteomic expression profile of bone microvascular endothelial cells of human femoral head against steroids-induced lesion].

OBJECTIVE: To explore the effect of icariin on the proteomic expression profile of bone microvascular endothelial cells of human femoral head against steroids-induced lesion using protein chip system in vitro. METHODS: Bone microvascular endothelial cells (BMECs) in cancellous bone of femoral head were isolated and harvested in vitro.The model of BMECs injury induced by glucocorticoid and icariin preconditioning was established. The apoptosis of BMECs were detected with terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL)methods. The proteomic expression profile of BMECs in each group were detected by protein chip system. RESULTS: The apoptosis rates of hydrocortisone groups (46.9%±5.8%, 78.0%±8.5%) were significantly higher than that of normal group(4.8%±1.3%), meanwhile the apoptosis rate of icariin+ hydrocortisone groups(15.2%±7.7%, 44.6%±5.3%)significantly decreased compared with hydrocortisone group (P<0.001). The results of protein chip showed that the expression of granulocyte colony-stimulating factor (G-CSF) in the hydrocortisone group decreased compared with the control group, meanwhile the expression of IL-4 increased. The expression of G-CSF in the icariin+ hydrocortisone groups increased compared with the hydrocortisone group, meanwhile the expression of IL-4 decreased.No appreciable change was found in the expression of apoptotic factors. CONCLUSION: The therapy effect of icariin for steroid-induced necrosis of femoral head might be related with the protective action to BMECs and the moderating effect of promoting the proteins expression of pro-angiogenesis factor and inhibiting expression of inflammatory factor.

An efficient algorithm for computing fixed length attractors based on bounded model checking in synchronous Boolean networks with biochemical applications.

Genetic regulatory networks are the key to understanding biochemical systems. One condition of the genetic regulatory network under different living environments can be modeled as a synchronous Boolean network. The attractors of these Boolean networks will help biologists to identify determinant and stable factors. Existing methods identify attractors based on a random initial state or the entire state simultaneously. They cannot identify the fixed length attractors directly. The complexity of including time increases exponentially with respect to the attractor number and length of attractors. This study used the bounded model checking to quickly locate fixed length attractors. Based on the SAT solver, we propose a new algorithm for efficiently computing the fixed length attractors, which is more suitable for large Boolean networks and numerous attractors' networks. After comparison using the tool BooleNet, empirical experiments involving biochemical systems demonstrated the feasibility and efficiency of our approach.

A model for the coordinated stepping of cytoplasmic dynein.

Cytoplasmic dynein play an important role in transporting various intracellular cargos by coupling their ATP hydrolysis cycle with their conformational changes. Recent experimental results showed that the cytoplasmic dynein had a highly variable stepping pattern including "hand-over-hand", "inchworm" and "nonalternating-inchworm". Here, we developed a model to describe the coordinated stepping patterns of cytoplasmic dynein, based on its working cycle, construction and the interaction between its leading head and tailing head. The kinetic model showed how change in the distance between the two heads influences the rate of cytoplasmic dynein under different stepping patterns. Numerical simulations of the distribution of step size and striding rate are in good quantitative agreement with experimental observations. Hence, our coordinated stepping model for cytoplasmic dynein successfully explained its diverse stepping patterns as a molecular motor. The cooperative mechanism carried out by the two heads of cytoplasmic dynein shed light on the strategies adopted by the cytoplasmic dynein in executing various functions.

Porous tantalum rods for treating osteonecrosis of the femoral head.

This study evaluated the outcomes of using porous tantalum rods for the treatment of osteonecrosis of the femoral head (ONFH). We performed core decompression and inserted porous tantalum implants in 149 patients (168 consecutive hips) with ONFH. Hips had large (65), medium (64), or small (39) lesions; 63 lesions were lateral, 68 were central, and 35 were medial. Conversion to total hip arthroplasty (THA) was the end point of this survey. A total of 130 cases (138 hips) were followed. The mean follow-up time was 38.46 ± 5.76 months; 43 hips (31%) were converted to or needed THA. Of the 43 hips requiring THA, 33 had large lesions, including 1 medial, 3 central, and 29 lateral lesions; 9 had medium, lateral lesions, and 1 hip had a small, lateral lesion. Bone grafting was used in 59 hips, with 3 hips failing; 40 of 79 hips without bone grafts failed. The sum distances between the tops of the rods and the lateral lesion boundaries (SDTL, mm) were measured in anteroposterior and lateral radiographs. In the failure and spared groups, the average SDTLs were 7.65 ± 2.759 and 0.83 ± 2.286 mm, respectively. The survival of porous tantalum rods used for treating early-stage ONFH was affected by the size and location of the lesion, whether or not a bone graft was used, as well as the distance between top of the rod and the lateral boundary of the lesion.

Effect of sponge volume fraction on the performance of a novel fluidized bed bioreactor.

A novel fluidized bed bioreactor (FBBR) was designed by integration of anaerobic granular activated carbon and aerobic sponge reactors. This FBBR was evaluated at different sponge volume fractions for treating a synthetic wastewater. Polyester urethane sponge with cube size of 1 × 1 × 1 cm and density of 28-30 kg/m(3) with 90 cells per 25 mm was used as biomass carrier. The results indicate that the FBBR could remove more than 93% of dissolved organic carbon (DOC). The highest nutrient removal efficiencies (58.2% PO4-P and 75.4% NH4-N) were achieved at 40% sponge volume fraction. The system could provide a good condition for biomass growth (e.g. 186.2 mg biomass/g sponge). No significant different performance in specific oxygen uptake rate was observed between 30, 40, and 50% sponge volume fractions.

A novel integrated assessment methodology of urban water reuse.

Wastewater is no longer considered a waste product and water reuse needs to play a stronger part in securing urban water supply. Although treatment technologies for water reclamation have significantly improved the question that deserves further analysis is, how selection of a particular wastewater treatment technology relates to performance and sustainability? The proposed assessment model integrates; (i) technology, characterised by selected quantity and quality performance parameters; (ii) productivity, efficiency and reliability criteria; (iii) quantitative performance indicators; (iv) development of evaluation model. The challenges related to hierarchy and selections of performance indicators have been resolved through the case study analysis. The goal of this study is to validate a new assessment methodology in relation to performance of the microfiltration (MF) technology, a key element of the treatment process. Specific performance data and measurements were obtained at specific Control and Data Acquisition Points (CP) to satisfy the input-output inventory in relation to water resources, products, material flows, energy requirements, chemicals use, etc. Performance assessment process contains analysis and necessary linking across important parametric functions leading to reliable outcomes and results.

[Prevalence of intestinal protozoan infections among rural children in Henan Province from 2014 to 2015].

OBJECTIVE: To investigate the prevalence and influencing factors of intestinal protozoan infections among rural children in Henan Province. METHODS: A total of 104 survey sites were sampled from 35 counties (cities) in Henan Province using the stratified cluster sampling method to investigate the prevalence of intestinal protozoan infections among rural children from 2014 to 2015. The trophozoites and cysts of intestinal protozoa were identified using the iodine staining method and the physiological saline direct smear method (one detection for one stool sample). The prevalence of intestinal protozoan infections was compared among rural children with different characteristics, and the factors affecting intestinal protozoan infections among rural children were identified. RESULTS: The overall prevalence of intestinal protozoan infections was 0.60% (40/6 771) among rural children in Henan Province from 2014 to 2015. There were 7 species of intestinal protozoa identified, and there was no species-specific prevalence (χ2 = 37.732, P = 0.000). No significant differences were found in prevalence of intestinal protozoan infections among rural children in terms of gender (χ2 = 1.793, P = 0.181), age (χ2 = 1.443, P = 0.486), occupation (χ2 = 0.219, P = 0.896) or ecological region (χ2 = 1.700, P = 0.637). In addition, terrain (χ2 = 2.311, P = 0.510), economic level (χ2 = 4.322, P = 0.229), source of drinking water (χ2 = 0.731, P = 0.393), eating raw vegetables (χ2 = 1.134, P = 0.287) and deworming (χ2 = 1.089, P = 0.297) had no remarkable effects on the prevalence of intestinal protozoan infections among rural children in Henan Province; however, the prevalence of intestinal protozoan infections varied significantly among rural children living in regions with different coverage of non-harmless toilets (χ2 = 10.050, P = 0.018). CONCLUSIONS: The prevalence of intestinal protozoan infections is low among rural children in Henan Province.