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Purpose This study is to compare the precision and safety of the orthopaedic robot with conventional fluoroscopy for assisted percutaneous sacroiliac joint screw implantation. Methods Retrospective analysis was performed on the clinical data of 57 patients with unstable posterior pelvic ring injuries who were admitted and met the criteria between January 2017 and January 2022. All of these patients underwent percutaneous sacroiliac joint screw implantation, and their clinical data were split into two groups based on the surgical technique: a RA group (robot-assisted implantation, 30 patients, 54 screws) and a CF group (conventional fluoroscopic freehand implantation, 27 patients, 42 screws). There were 96 screws placed in total. The durations of the two groups’ operations, fluoroscopy examinations, fluoroscopy doses, total number of fluoroscopies, and intra-operative guide pin applications were noted and compared. On post-operative CT scans, the placement of each screw was assessed using the Gertzbein-Robbins classification. Finally, imaging Matta criteria were used to assess the sacroiliac joint fracture reduction. The Majeed functional score was used to assess clinical function. Results Both groups successfully completed 57 procedures in total. In both groups, there were no consequences from vascular injury, wound infection, or urinary tract infection. Additionally, there were no complications from robotic-induced nerve injury, operating time, fluoroscopic dose, and the frequency of fluoroscopic; the number of percutaneous punctures in the RA group was lower than that of the CF group.There were statistically significant differences between the aforementioned data (P P > 0.05). According to the modified Gertzbein-Robbins classification criteria, the 54 screws implanted in the RA group were classified as follows: class A (45), class B (5), class C (4), and class D (0); the accuracy rate of the implants was 92.59%. Forty-two screws implanted in the CF group, 30 screws were defined class A, class B (3), class C (7), and class D (2). The accuracy rate of the implants was 78.57%(χ2 = 3.967, P 0.05). Conclusion “TiRobot” robot-assisted screw implant treatment for unstable posterior pelvic ring injury has a greater success rate than traditional surgery as compared to conventional percutaneous screw implant. It is a precise, secure, and minimally invasive surgical technique that can also be applied to severe pelvic injuries even congenital sacral deformities.

Confined metal clusters as sub-nanometer reactors for electrocatalytic N2 reduction reaction (eNRR) have received increasing attention due to the unique metal-metal interaction and higher activity than single-atom catalysts. Herein, the inspiration of the superior capacitance and unique microenvironment with regular surface cavities of the porous boron nitride (p-BN) nanosheets, we systematically studied the catalytic activity for NRR of transition-metal single-clusters in the triplet form (V3, Fe3, Mo3 and W3) confined in the surface cavities of the p-BN sheets by spin-polarized density functional theory (DFT) calculations. After a two-step screening strategy, Mo3@p-BN was found to have high catalytic activity and selectivity with a rather low limiting potential (–0.34 V) for the NRR. The anchored Mo3 single-cluster can be stably embedded on the surface cavities of the substrate preventing the diffusion of the active Mo atoms. More importantly, the Mo atoms in the Mo3 single-cluster would act as “cache” to accelerate electron transfer between active metal centers and nitrogen-containing intermediates via the intimate Mo-Mo interactions. The cooperation of Mo atoms can also provide a large number of occupied and unoccupied d orbitals to make the "donation–backdonation" mechanism more effective. This work not only provides a quite promising electrocatalyst for NRR, but also brings new insights into the rational design of triple-atom NRR catalysts.

Considerable efforts have been made to enhance the hydrogen evolution reaction (HER) catalytic performance of Janus MoSSe monolayer, which have been considered to be a promising candidate due to the unique asymmetry structure. However, the activation effect remains non-optimal for the inert Janus MoSSe basal plane at present. Herein, a train of transition metal (TM) atoms were anchored on the S-/Se-/Mo-defective MoSSe basal plane to screen effective TM single-atom catalysts for HER through density functional theory (DFT) computations. Interestingly, the single Co atom anchored on Mo-defective MoSSe and the single Zn or Cd atom anchored on S-defective MoSSe were judged to possess excellent HER performance yielding a near-zero ΔGH (ΔGH = −0.050, −0.095, −0.098 eV, respectively), which is comparable to the optimized Pt-SACs. The enhanced HER activity is attributed to the doping of TM atoms (Co, Zn and Cd) which improves the conductivity of the original MoSSe and offers unoccupied states near the Fermi level decreasing the energy barrier of electrons transfer between H and TMs@MoSSe surface. In addition, the change of unoccupied antibonding states of active atoms leads to appropriate interaction between the active sites and H. The hybridization between H-s orbital and the TMs@MoSSe systems around the Fermi level also suggests the formation of stable bonding-antibonding hydrogen adsorption states. This work reveals an effective way of activating MoSSe basal plane for HER.

Objective To assess the long‐term clinical efficacy of TiRobot‐assisted percutaneous cannulated screw fixation in the treatment of femoral neck fractures. Methods This retrospective study included 50 patients with unilateral femoral neck fractures who were treated with TiRobot‐assisted percutaneous cannulated screw fixation from September 2017 to May 2018. After at least 2 years of follow‐up, the results of treatment, including operation duration, frequency of fluoroscopy use, intraoperative bleeding, hospital stay, medical expense, screw placement accuracy, rate of fracture healing and necrosis of the femoral head, and Harris hip scores at the last follow up, were recorded and compared with those of 83 matched patients who underwent conventional manual positioning surgery. Results The TiRobot group had longer operation duration (83.3 ± 31.2 min vs 44.1 ± 14.8 min) and higher medical expenses (28,407.1 ± 7498.0 yuan vs 22,672.3 ± 4130.3 yuan) than the conventional group. The TiRobot group had significantly less intraoperative bleeding (11.3 ± 7.3 mL vs 51.6 ± 40.4 mL) and shorter hospital stay (8.6 ± 2.8 days vs 11.1 ± 3.41 days) than the conventional group. Screw parallelism (1.32° ± 1.85° vs 2.54° ± 2.99° on anteroposterior radiograph; 1.42° ± 2.25° vs 3.09° ± 3.63° on lateral radiograph) and distance between screws (58.44 ± 10.52 mm vs 39.69 ± 12.17 mm) were significantly improved. No significant difference was found between the two groups in terms of the use of fluoroscopy (40.1 ± 28.5 times vs 38.6 ± 21.0 times) and Harris hip scores at the last follow‐up (93.2 ± 10.3 points vs 88.4 ± 11.9 points). Two cannulated screws penetrated the femoral head during manual insertion in the conventional group but not in the TiRobot group. The rate of nonunion and necrosis of the femoral head in the TiRobot group was reduced compared with that in the conventional group (0 vs 7.2%; 6.0% vs 24.1%). Conclusion TiRobot‐assisted percutaneous cannulated screw fixation of femoral neck fractures is accurate and minimally invasive and helps in reducing late complications, particularly necrosis of the femoral head and nonunion of fractures., TiRobot‐assisted percutaneous cannulated screw fixation of femoral neck fractures is accurate and minimally invasive, and helps in reducing late complications, particularly necrosis of the femoral head and nonunion of fracture.

The vital role of the spin polarization in the electrocatalytic N2 reduction reaction (eNRR) stimulates us to explore the potential of the newly discovered two-dimensional (2D) vdW ferromagnetic materials as NRR electrocatalysts. Here, using density functional theory (DFT) computations, we report the first theoretical prediction that the single-layer defective Fe3GeTe2 acts as a 2D ferromagnetic material toward the NRR with outstanding electrocatalytic activity and high selectivity. Notably, all six hydrogenation steps are exothermic and spontaneous. The highly centralized spin-polarization on the exposed Fe4 center in defective Fe3GeTe2 leads to strong backdonation and substantial activation of the NN triple bond. Moreover, the metallic character of the defective Fe3GeTe2 ensures high-speed transport of carriers. This work not only provides a quite promising electrocatalyst for the NRR but also promotes the application of emerging 2D ferromagnets in the field of energy conversion.

Using shear wave elastography (SWE) and contrast enhanced ultrasound (CEUS)to examine carotid plaques with different echoes, and explore a reliable method to quantify characteristics associated with vulnerable carotid plaques.2D ultrasound, SWE and CEUS were performed on 244 carotid plaques, and the echoes were evaluated according to the Gray-Weale classification scale and gray-scale median (GSM), and the mean Young's modulus (YM) of the plaque was measured and the intraplaque neovascularization was observed to investigate the relationship between carotid plaque types with different echo characteristics, GSM and the values of each parameter of YM and CEUS. The relationship between GSM and YM and CEUS values was investigated.The differences between GSM values (F = 49.742, P0.001), with the maximum, mean, and minimum YM values of ultrasound elastography (P0.001), and with the number (P0.001) and density (P = 0.047) of neovascularization on CEUS were statistically significant for the different echogenic types of plaques, and the lower the echogenicity of the plaque, the lower the GSM values (r = 0.632, P0.001), the smaller the YM values (all r0, P0.001), and the higher the neovascularization number and density values (r0, P0.001); and there were also statistically significant differences between the above indicators in the vulnerable and stable plaque groups (all P0.05).GSM, SWE, and CEUS techniques can quantitatively evaluate the vulnerability of different echo carotid plaques in a more comprehensive and objective manner, which may help clinical identification of vulnerable plaques, and provide important reference values for early diagnosis and treatment in clinical practice.

Inspired by the recent practical application of two-dimensional (2D) nanomaterials as gas sensors, catalysts, and materials for waste gas disposal, herein, the adsorption behaviors of environmental gas molecules, including NO, CO, O

BACKGROUND To investigate the preventive effect of elastic stockings on deep vein thrombosis (DVT) after orthopedic surgery by literature search and meta-analysis. METHODS PubMed, Embase and Cochrane were selected as the search database platforms to search the literature of randomized controlled trials related to elastic stockings and DVT published from 2008 to date. Revman 5.3.5 software was used for statistical analysis of the data to obtain forest and funnel plots. RESULTS In this study, 90 studies were initially screened and 7 were finally included, covering a total of 3,116 patients. Meta-analysis showed that the 7 studies had statistical heterogeneity (I2=32%, P=0.18), so a random effect model was used. The obtained statistic was [odds ratio (OR) =0.59, 95% confidence interval (CI): (0.34, 1.03)], the statistical effect size was Z=1.84, P=0.07, and the difference was not statistically significant, so a stepwise sensitivity analysis was performed by the exclusion method. One study was excluded, and the remaining 6 showed homogeneity (I2=0%, P=0.46). They were analyzed by subgroup according to the type of operation: ankle surgery or hip and knee arthroplasty. The internal literatures of each subgroup were homogeneous: ankle surgery subgroup (I2=0%, P=0.43), hip and knee arthroplasty subgroup (I2=0%, P=0.88). Therefore, fixed effect mode analysis was used, and the effect size of elastic stockings after ankle surgery was Z=3.65, P=0.0003, while the effect size of elastic stockings in the hip and knee arthroplasty subgroup was Z=1.23, P=0.22. DISCUSSION Elastic stockings had an obvious preventive effect on DVT in patients undergoing ankle surgery, but not in patients undergoing lumbar, knee or spinal surgery. It is necessary to combine anticoagulant drugs and other physical therapies to prevent DVT.

MoS2 is a promising candidate for hydrogen evolution reaction (HER), while its active sites are mainly distributed on the edge sites rather than the basal plane sites. Herein, a strategy to overcome the inertness of the MoS2 basal surface and achieve high HER activity by combining single-boron catalyst and compressive strain was reported through density functional theory (DFT) computations. The ab initio molecular dynamics (AIMD) simulation on B@MoS2 suggests high thermodynamic and kinetic stability. We found that the rather strong adsorption of hydrogen by B@MoS2 can be alleviated by stress engineering. The optimal stress of −7% can achieve a nearly zero value of ΔGH (~ −0.084 eV), which is close to that of the ideal Pt-SACs for HER. The novel HER activity is attributed to (i) the B-doping brings the active site to the basal plane of MoS2 and reduces the band-gap, thereby increasing the conductivity; (ii) the compressive stress regulates the number of charge transfer between (H)-(B)-(MoS2), weakening the adsorption energy of hydrogen on B@MoS2. Moreover, we constructed a SiN/B@MoS2 heterojunction, which introduces an 8.6% compressive stress for B@MoS2 and yields an ideal ΔGH. This work provides an effective means to achieve high intrinsic HER activity for MoS2.

The electrocatalytic reduction of naturally abundant N2 to NH3 is an attractive approach to replace the Haber–Bosch nitrogen-fixation process that causes enormous energy consumption and greenhouse gas emissions. However, designing high-performance catalysts toward the electrocatalytic N2 reduction reaction (eNRR) remains one of the greatest challenges in this area. Herein, high-throughput screening of catalysts for the NRR among a series of transition metal atoms supported on a defective hexagonal boron nitride (h-BN) nanosheet is performed through spin-polarized density functional theory (DFT) computations. Strikingly, among the 18 candidates, the V/Tc atom anchored on a defective h-BN monolayer (V@BN and Tc@BN) showed good NRR activity with relatively low onset potentials. Particularly, V@BN was found to exhibit outstanding catalytic activity for the NRR via an enzymatic pathway with an extremely low overpotential of 0.25 V. The value is significantly lower than that on the Ru (0001) stepped surface that has the best NRR catalytic performance among bulk metal catalysts. The novel NRR activity of V@BN is attributed to the enhanced electrical conductivity due to V-doping, the “donation–backdonation” process for N2 activation, and the highly centralized spin-polarization on the V atom. This work not only provides a quite promising catalyst for the NRR but also provides new insights for the rational design of single-atom NRR catalysts.

Lithium ion batteries (LIBs) with Si/graphite composites anode promise a high energy density larger than 400 Wh kg−1 with low costs, however, they still suffer from rapid performance degradation and potential safety hazard at cold climate. This is mainly associated with the fragile solid electrolyte (SEI) layer and the formation of Li dendrite. Here, we report on designing of electrolyte additives which endows a capacity retention of 66.7% over 200 cycles and an excellent rate performance with Si (10 wt%)/graphite composite anode. Moreover, the initial coulombic efficiency (CE) achieves 87% and rapidly approaches 100% in the 2nd cycle. The high-ductility organic/inorganic solid electrolyte interfaces (SEI) layer, which is composed by ROSO2Li and LiF, contribute to the enhanced performance. The introduction of Diethyl Sulfite (DES) promotes the rapid defluorination of Fluoroethylene carbonate (FEC) and polymerization of sulfide to form the organic layer during the initial discharging. Our results provide a facile but practical method to enhance the low-temperature performance and prove the way of commercial LIBs which could be operated at cold climate.

Two-dimensional (2D) hydrogen evolution reaction (HER) electrocatalysts have attracted great attention due to their unique electronic properties and high activities. Recently, a new 2D monolayer material of MoSi2N4 has been successfully synthesized and its semiconducting property and excellent ambient stability have also been demonstrated (Science 2020, 369, 670). Here, a systematic screening of catalysts for HER among N- and Si-defective MoSi2N4-supported single non-precious transition metal (TM) and non-metal (NM) atom catalysts is performed by means of density functional theory (DFT) calculations. Interestingly, the single O/P/Fe/Nb atom doped N-(Si-) defective MoSi2N4 monolayer were found to possess excellent HER performance presenting a near-zero ΔGH, which is comparable to or even better than the state-of-the-art Pt-based materials. Moreover, the novel HER activities of some TM doped structures were explained by the “states filling” model. The energy level of the first available unoccupied states for accommodating hydrogen drops after the introduction of TM atom, which modulates the hydrogen binding strength. This work opens the door for the application of MoSi2N4 monolayer and other related 2D materials in the field of energy conversion.

Aims Post-fracture calcium and phosphorus excretion is greater than influx, which might be caused by stress. Glucocorticoid is known to enhance calcium and phosphorous excretion, and hydrogen sulfide (H2S) has been shown to exert inhibitory effects on glucocorticoid. Therefore, this study explored whether H2S could inhibit calcium and phosphorus loss after fracture by regulating glucocorticoid and/or its receptor. Main methods The following properties were analyzed in rats with femur fractures: serum and urinary calcium and phosphorus (by colorimetry); bone turnover markers alkaline phosphatase, serum type 1 collagen amino terminal peptide, type 1 procollagen carboxy terminal peptide, and anti-tartaric acid phosphatase (by ELISA); factors related to calcium-phosphorus metabolism including glucocorticoid, parathyroid hormone, calcitonin, fibroblast growth factor 23, and 1,25(OH)2D3 (by ELISA); and sulfhydration of glucocorticoid receptor α in the kidney (by immunoprecipitation linked biotin-switch assay), after supplementing with mifepristone, the H2S donor GYY4137 or H2S generating enzyme inhibitors aminooxyacetic acid and propargylglycine. Key findings Serum H2S decreased and glucocorticoid secretion increased in rats post-fracture. The glucocorticoid receptor inhibitor mifepristone partly blunted calcium and phosphorus loss. Furthermore, supplementation with GYY4137 reduced glucocorticoid secretion; inhibited glucocorticoid receptor α activity by sulfhydration; downregulated vitamin D 1α-hydroxylase expression; and upregulated 24-hydroxylase, calbindin-D28k, and sodium phosphate cotransporter 2a expression in the kidney; thereby inhibiting calcium and phosphorus loss induced by fracture. Moreover, inhibiting endogenous H2S generation showed opposite effects. Significance Our findings suggest that H2S antagonized calcium and phosphorus loss after fracture by reducing glucocorticoid secretion and inhibiting glucocorticoid receptor α activity by sulfhydration.

MoS2, as a low-cost catalyst for hydrogen evolution reaction (HER), suffers from poor catalytic performance on the basal plane. Herein, by doping 19 main-group elements on the S-defective MoS2 nanosheet, the most promising MoS2-based catalysts for the HER are screened with high-throughput density functional theory (DFT) calculations. Remarkably, the doping of main-group elements except chalcogens can improve the activity of the MoS2 basal plane to a certain extent. The S-defective MoS2 monolayer doped with In/Ge atom (In3@MoS2 and Ge3@MoS2) show excellent HER performance, and their reaction barrier is even lower than that of commercial Pt/C catalyst. In In3@MoS2 and Ge3@MoS2, the In/Ge atoms act as electron donors to increase the unoccupied anti-bonding orbital, which enhances the interaction of In/Ge-H bonding. On the other hand, the unique co-existence of electron-depletion and electron-accumulation regions near In/Ge atoms enables the adsorption of free radical H to be moderate. Moreover, the In/Ge atoms also increase the conductivity of MoS2, especially the In atom brings a new impurity state near the Fermi level. This work presents a promising strategy for exploiting high-performance MoS2-based catalysts for HER, and would stimulate more researchers to optimize other two-dimensional materials by doping main-group elements for HER.

Recently, 2D ferromagnets have emerged as a hot research topic, especially after the exfoliation of monolayer ferromagnetic Fe3GeTe2 from its bulk structure (Nature 2018, 563, 94; Nat. Mater. 2018, 17, 778). In this work, we systematically report the adsorption behavior of CO, CO2, H2, H2O, NO, and O2 on the pristine and Te-deficient Fe3GeTe2 (FGT and d-FGT) monolayer using hybrid density functional theory. We find that the toxic gas molecules (CO and NO) and O2 molecular are chemically anchored at the surface of the pristine FGT, while the H2O, CO2, and H2 are physically associated with FGT. Interestingly, the introduction of Te deficiency would significantly enhance the covalent interactions between the substrate and the gas molecules, especially for CO2 and H2O, whose adsorption type has evolved from physisorption to chemisorption. Furthermore, the adsorption capacity of (d-)FGT to gas molecules is found to be stronger than that of the two well-studied 2D materials: MoS2 and MXenes. Meanwhile, the adsorption changes the electronic structure of (d-)FGT but does not change the metallicity of FGT. This work provides a valuable reference for the application of 2D metallic ferromagnetic materials in the field of catalysis, sensors, gas storage, and environmental remediation.

A central issue underlying end-to-side neurorrhaphy technique is whether injury to the donor nerve fibers is necessary for successful reinnervation of the recipient nerve. To address this question, the authors developed a novel atraumatic end-to-side neurorrhaphy model that uses the preexisting anatomical structure of the median nerve as the Y-chamber to study the mechanism of collateral sprouting.In this rat forelimb model, the authors transected the musculocutaneous nerve and the lateral head of the median nerve, and coapted their distal stumps together. In this model, the authors use the medial head of the median nerve as the donor nerve, and the lateral head of the median nerve (distal stump) as a Y-shaped chamber, which provided structural connection to the recipient musculocutaneous nerve in end-to-side fashion.Three months after surgery, converging histologic, electrophysiologic, and behavioral observations confirmed the successful reinnervation of the recipient nerve. Retrograde labeling indicated that sensory fibers exhibited greater collateral sprouting than observed for motor fibers. Interestingly, fluorescence of these collateral sprouting fibers was present only when the median nerve lateral head was attached to the musculocutaneous nerve of the biceps, indicating that factors derived from the denervated tissue likely induced the collateral sprouting in this model.The authors' findings provide strong evidence that collateral sprouting can be robustly initiated independent of donor nerve fiber injury. The authors' model can accelerate the understanding of the mechanism underlying end-to-side neurorrhaphy and the optimization of its clinical use.

Correlation analysis is both popular and useful in a number of social networking research, particularly in the exploratory data analysis. In this paper, three well-known and often-used correlation coefficients, Pearson product-moment correlation coefficient, Spearman, and Kendall rank correlation coefficients, are compared from definition to application domain. Based on the characteristics of the pump's vibration dataset, the nonparametric and distribution-free Spearman rank correlation coefficient is introduced to analyze the relationship between the pump's working state and each of the 207'880 variables. The percentage of variables and exact variables' tables with high Spearman's correlation coefficients for states I and II, states I and III, states II and III, and three states in different files are obtained respectively, which has important valuation for the future research of the unsupervised machine learning system. Copyright © 2015 John Wiley & Sons, Ltd.

Background Fracture is a common disease; many factors affect fracture healing. Recent studies have confirmed that hydrogen sulfide (H2S) plays an essential role in bone formation, but most of these studies are drawing conclusions based on animal experiment; whether H2S could promote fracture healing in patients is still unclear. We aim to investigate the change of serum H2S in fracture patients, and analyze its effort on fracture healing. Methods This is a single-center, prospective cohort study. Patients with spinal or limb fracture will be recruited. Patient's serum and urine will be collected at baseline for examination (serum H2S, β-CTX, OC, PINP, 25-OH-VitD3, S-CTX, urinary calcium, and urinary creatinine). All patients will be followed-up for 24 months in outpatients settings, the image of X-ray or CT will be reviewed and fracture healing will be judged by 2 experienced orthopedic physicians. The difference in serum parameters especially H2S will be compared between patients with fracture healed within 9 months and those with fracture unhealed at 9 months. Discussion Results of the trial could provide insight into influence of H2S on fracture healing. Ethics and dissemination The study was approved by the ethics committee of School of Medicine UESTC & Sichuan Provincial People's Hospital Ethics Committee. All the participants will be asked to provide written informed consent before data collection. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conferences.

The purpose of this study was to compare the outcomes of different numbers of intercostal nerve (ICN) transfers for elbow flexion and to determine whether age, body mass index (BMI), type of injury, and preoperative delay influence the outcomes. From 2004 to 2010, 32 (30 included) consecutive patients underwent ICN transfer to the musculocutaneous nerve following brachial plexus injury. Elbow flexion strength was evaluated according to the British Medical Research Council (BMRC) grading system. Of nine patients who received two ICN transfers, six (66.7%) recovered with useful elbow flexion compared with 14 of 17 (82.4%) patients who received three ICN transfers. Of the four patients with four ICN transfers, three (75%) achieved useful recovery. Statistical analysis showed no significant difference. There is no significant difference among the outcomes of two, three, and four ICN transfers to the musculocutaneous nerve. Two ICN transfers are sufficient for useful recovery of elbow flexion. Younger patients achieve better results.

This paper evaluates the similarity between two time series generated by two sensors manufactured by different companies, trying to provide some valuable information upon choosing sensors of different brands. Spearman correlation coefficient analysis and Euclidean distance measurement have been applied. Experiment is carried out on R. Visualization of the studied time series and results of similarity measured over time series by Spearman correlation coefficient and Euclidean distance are presented. Besides, the consistency and inconsistency in the analysis results of two measurements have been discussed in this paper.

Cycle life of traction battery has a direct effect on the use of electric vehicles. In this work, both normal cycle life and bus cycle life testing were investigated. Battery life can be tested with the bus-cycle procedure similar to the real use on road. Both the fading of capacity and the increase of the internal resistance should be tested and evaluated during life testing and the overall merit of battery attenuation should be given. All the discharge energy during life testing should be calculated, which can give the information of the real usable energy during all its life time.

In this paper, an algorithm based on traffic prediction is proposed, in bid to predict instantaneous traffic in ONU, guide higher-priority bandwidth allocation, and avoid "T+2" queuing delay. That is the Dynamic Bandwidth Allocation (Pre_DBA) for EPONs, which also includes a prediction corrected mechanism, to maximize bandwidth utilization. As is verified in the designed simulation, this algorithm, apart from ensuring effectiveness and fairness of the premise, is quite able to alleviate delay and jitter in higher-priority services as well.

Objective: To evaluate the risk of developing pulmonary edema in women exposed to nifedipine, magnesium sulfate (MgSO4), or both in a preterm setting. Study design: We carried out a retrospective case-control study at a large tertiary care center from 2007 to 2012. Cases of pulmonary edema were age, and gestational age matched to controls at a ratio of 1 case to 4 controls. Logistic regression analysis was used to estimate the effect of nifedipine and/or MgSO4 on the development of pulmonary edema while controlling for predetermined confounding variables. Stepwise logistic regression analysis was used to evaluate additional risk factors of pulmonary edema. Results: A total of 150 charts were reviewed (28 cases and 122 controls). Nifedipine did not increase the odds of developing pulmonary edema [adjusted odds ratio (OR)=1.22 (confidence interval (CI) 0.50, 3.01), P=0.67], whereas exposure to MgSO4, or both MgSO4 and nifedipine, significantly increased the risk of developing pulmonary edema [adjusted OR=3.91 (CI 1.44, 10.65), P=0.008 and adjusted OR=4.75 (CI 1.15, 19.71), P=0.032, respectively]. In the stratified analysis, this association persisted even in nonpreeclamptic women [nifedipine: adjusted OR=0.91 (CI 0.33, 2.52), P=0.852; MgSO4: adjusted OR=3.51 (CI 1.26, 9.76), P=0.016; both: adjusted OR=3.39 (0.76, 15.07), P=0.108]. Other independent risk factors for pulmonary edema were multi-fetal pregnancy, azithromycin, and erythromycin administration. Conclusion: MgSO4 treatment is strongly associated with the development of pulmonary edema when used either as a tocolytic agent or for seizure prophylaxis. In light of the availability of safer alternatives, MgSO4 should be used for tocolysis only in cases whereby the benefits clearly outweigh the risks.

The degree of impairment of ventilation and exercise performance after unilateral diaphragmatic paralysis (UDP) induced by phrenic nerve injury has been controversial due to heterogeneity in the published clinical studies. The aim of this study was to assess the effect of isolated UDP on breathing and exercise performance in conscious rats. Breathing was measured by unrestrained whole body plethysmography during quiet breathing and after moderate aerobic exercise. Additionally, incremental exercise testing was performed to evaluate the effects of intensive activity. The results demonstrated that complete UDP in rats resulted in a permanent decrease of peak inspiratory flow at rest breathing. Nevertheless, adequate ventilation could be maintained, and the breathing pattern was unaltered due to a strong compensatory mechanism and central re-coordination initiated by UDP. After being affected at an early stage, the ventilatory response to exercise was gradually regained and subsequently restored.

Farmers in developing countries face relatively large income risk and have limited access to formal financial products that can help them manage their risk. We present results from a randomized controlled trial in rural China designed to understand whether a small change in the timing of a premium payment for a swine insurance contract helps to overcome an important barrier to insurance demand and, if so, whether the resulting increase in insurance would allow farmers to increase investment in activities that expose them to the risk being insured against. We find that insurance take-up is three times higher among those who were given the option to pay at the end of the insured period. We use the random variation in insurance take-up thus induced to estimate the impact of insurance on investment. We find a positive impact on investment, which suggests that without insurance, farmers were not able to fully insure; that the new payment plan helped farmers to overcome an important barrier to insurance purchases; and that encouraging insurance purchases in this way can have a positive long-term effect on the income and welfare of rural households in China.

Electrification is regarded as the mainstream for future automobile power-train in order to cope with the impending energy and environmental problems. The technology of electric vehicle (EV), including battery powered vehicle, hybrid vehicle and fuel cell vehicle, has been investigated thoroughly for more than two decades in China. Many remarkable progresses have been achieved. In this paper, the R & D of electric vehicle technology in China are introduced. Both battery and motor development for electric vehicle application are summarized. The technology trend of electric motor drive is discussed accompanying with the introduction of the practice in electric motor drive research in Chinese Academy of Sciences.

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