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Profiled membranes, the membranes with microstructures on one side or two sides, are expected to be a viable alternative to the spacers and enhance the power output of the reverse electrodialysis (RED) process. However, there are some problems for the present single-sided profiled membranes such as flow stagnating and insufficient fluid mixing. As for double-sided profiled membranes, the membrane preparation and exact stack assembling are still difficult. With respect to these problems, a single-sided wave-profiled membrane with wavy sub-corrugations as additional mixing promoters is proposed in this study. Based on the Computational Fluid Dynamics method, the flow and mass transfer characteristics in the wave-profiled membrane channel and several other channels (for purposes of comparison) are simulated. Results show that the single-sided wave-profiled membrane channel has more advantages than the single-sided pillar-profiled membrane channels especially at low Reynolds numbers typically used in RED applications, although its performance is still inferior to that of the double-sided chevron-profiled membrane channel and woven spacer channel. Furthermore, it can be proved that the wavy sub-corrugations can enhance the mass transfer and reduce the concentration polarization, while they have a better influence on the surface where the sub-corrugations are located.

Efficient electrode materials are essential to convert salinity gradient energy into oxidative degradation energy and electrical energy by reverse electrodialysis reactor (REDR). In this context, comparative experiments of REDR using different anodes (Ti/IrO

In this paper, the synthetic methyl orange (MO) dyeing wastewater treated by a reverse electrodialysis reactor (REDR) with 40 member pairs was investigated first. The boron-doped diamond (BDD) and carbon felt were adopted as an anode and a cathode in the REDR. The influences of operation parameters on the chemical oxygen demand (COD) removal efficiency were detected and explored. Then, a mathematical model of organic mineralizing was developed for the REDR to predict the variation of COD removal efficiency with treating time under the different operation conditions. Finally, the energy consumption of the wastewater treated by the REDR was analyzed. The results showed that raising the working fluid flowing velocity and electrode rinse solution flowrate improved the COD removal efficiency and instantaneous current efficiency (ICE), and reduced the total energy consumption (TEC) of the REDR. Raising the initial MO concentration could significantly reduce the TEC despite the COD removal efficiency being near. Since the main energy consumed by the REDR was salinity gradient energy (SGE) from waste heat conversion or the natural environment, the energy cost of REDR treating wastewater has been reduced significantly.

Reverse electrodialysis (RED) heat engine is a novel technology to convert low grade heat into electricity. Through combining the multi-effect distillation (MED) with RED, the so-called MED-RED heat engine has received increasing attention over the recent years. In this paper, a comprehensive theoretical exergy analysis for the MED-RED heat engine has been carried out based on a validated mathematical model. And the influences of relevant operation and design parameters on the exergetic performance of the heat engine were investigated. The results showed that the preheater, condenser and RED unit were main sources of exergy destruction in the heat engine. The total relative exergy destruction of these three components was 59.8% and the exergetic efficiency of the heat engine reached 4.7% under the design condition. Moreover, elevating the temperature of hot water had a negative effect on enhancing the exergetic performance of the heat engine. On the contrary, increasing the concentration of initial brackish solution or the number of effect evaporators in the MED was helpful for improving the exergetic performance of the heat engine. Finally, discussion in terms of improving the exergetic performance of the heat engine was carried out and relevant approaches were presented.

Reverse electrodialysis heat engine (REDHE) is an effective technology to harvest salinity gradient energy (SGE) driven by low grade heat. In order to improve the energy conversion efficiency of it, one practical way is to enhance the capturing SGE ability of the reverse electrodialysis (RED) unit. To achieve that, the promising multi-stage RED (MSRED) method is proposed. In this paper, two strategies for MSRED, i.e., individually control (Strategy I) and serial control (Strategy II) respectively, were theoretically compared and analyzed. The results showed that Strategy II is more suitable in practice, although its performance is slightly inferior compared with Strategy I. After that, the influence of feed solution velocity, thickness of high concentration solution compartments, concentrations of feed solutions and flow arrangement on the relevant key performance indicators of MSRED in the two strategies were investigated. And results demonstrated that thickening compartments of high concentration solution, increasing the concentration of high concentration feed solution and adopting counter-flow arrangement are all more effective for elevating the performance of MSRED than increasing feed solution velocity. Furthermore, increasing the concentration of low concentration feed solution overly has a significant negative impact on the performance of MSRED.

By developing the mathematical model of a serial multi-stage reverse electrodialysis reactor (REDR) system for wastewater treatment, this paper numerically simulates the degradation process of azo dye (methyl orange) dyeing wastewater. The operation performances of the serial system with an anode and cathode synergetic degradative circulation mode are explored by numerical simulation. The influences of operation parameter variations on key performance indicators are investigated and discussed. Results indicate that the serial system can achieve excellent electricity conversion efficiency and degradative performance under an appropriate output current condition. A high initial MO concentration and electrode rinse solution (ERS) flowrate are helpful to improve the treatment performance of the system. A low concentrated solution (CS) concentration is beneficial for raising the electricity conversion efficiency and reducing the total energy consumption (TEC).

Developmental hip dysplasia (DDH), one of the common hip disorders, is a condition that acetabular defects at birth progress gradually during the growth and cause the abnormal biomechanical environment. Subsequently, the secondary pathological changes range from femoral head subluxation, degeneration of cartilage in weight-bearing area, focal necrosis of femoral head to severe osteoarthritis.

Osteonecrosis of the femoral head (ONFH) is a refractory disease caused by the disruption or impairment of blood supply to the femoral head. It is followed by the death of osteocytes and bone marrow as well as subsequent bone repair, which in turn leads to the structural changes and collapse of the femoral head, and joint dysfunction. Since Munro first described ONFH in 1738, scholars around the world have conducted a lot of research work on it. This disease is more likely to occur in young and middle-aged people (30–50 years old), mostly bilateral, and the risk is much higher in Asian populations. Its incidence is estimated to be 10,000 to 20,000 new cases per year in the United States. Meanwhile, there are 50,000–100,000 new cases per year in China, which is the highest in the world. Once ONFH occurs in the patient, the necrosis of trabecular bone and bone marrow in the femoral head will take place. Then the cystic changes in the subchondral bone and collapses of articular cartilage ensue, leading to the secondary joint degeneration and osteophytes formation. It eventually leads to painful osteoarthritis, with the loss of hip function. The difficulty of the ONFH treatment and the subsequent high disability rate has brought huge economic and spiritual burdens to the patients, their families, and the entire society.

Failed treatment of intertrochanteric (IT) femoral fractures leads to remarkable disability and pain, and revision surgery is frequently accompanied by higher complication and reoperation rates than primary internal fixation or primary hip arthroplasty. There is an urgent need to establish a profound strategy for the effective surgical management of these fragile patients. Salvage options are determined according to patient physiological age, functional level, life expectancy, nonunion anatomical site, fracture pattern, remaining bone quality, bone stock, and hip joint competency. In physiologically young patients, care should be taken to preserve the vitality of the femoral head with salvage internal fixation; however, for the elderly population, conversion arthroplasty can result in early weight bearing and ambulation and eliminates the risks of delayed fracture healing. Technical challenges include a difficult surgical exposure, removal of broken implants, deformity correction, critical bone defects, poor bone quality, high perioperative fracture risk, and prolonged immobilization. Overall, the salvage of failed internal fixations of IT fractures with properly selected implants and profound techniques can lead to the formulation of valuable surgical strategies and provide patients with satisfactory clinical outcomes.

Timing of surgery is the most critical prognostic factor for hip osteonecrosis treated with free vascularized fibular grafting (FVFG). Bone marrow lesion (BML) on MRI usually occurs immediately before femoral head collapse. We conducted a retrospective cohort study to evaluate whether the noncollapsed hips with BML can benefit from FVFG. Consecutive patients undergoing modified FVFG were identified from our clinical repository between January 2014 and December 2014. Based on whether BML was pre-operatively detected, the four year radiographic and clinical outcomes were compared. In the BML cohort, 22 of 53 hips (42%) showed radiographic signs of osteonecrosis progression, which was significantly higher than that in the control cohort (8 of 49, 16%; P = 0.005). The BML hips showed a significantly lower pre-operative Harris Hip Score (HHS) than those without BML (77.8 vs. 85.5, P = 0.046), whereas no such difference was observed in the final HHS or its post-operative improvement (HHS 90 vs. 94, P = 0.397; HHS improvement 12 vs. 8, P = 0.067). In the subgroup of patients with a pre-operative HHS lower than 80, BML hips were associated with a slightly lower final HHS than hips without BML. Four of 5 (80%) failed hips with BML had a poor pre-operative hip function. BML indicates the last chance for a reproducible improvement in the treatment of hip osteonecrosis with FVFG before collapse. However, the concomitant lower pre-operative HHS (

Objective This study was performed to investigate the reliability of the height of pertrochanteric fractures as a predictor of lateral wall fractures after cephalomedullary nailing and provide a simple way to determine the threshold value. Methods We performed a prospective randomized clinical study of 50 consecutive patients who underwent measurement of the height of the pertrochanteric fracture and the tangent line to the superior margin of the contralateral femoral neck. The preoperative and postoperative integrity of the lateral wall was evaluated by computed tomography. Results The pertrochanteric fracture height was significantly lower in patients with than without intraoperative lateral wall fractures (15.6 vs. 28.5 mm, respectively). The threshold value of the fracture height was 20.445 mm, which was not significantly different from the mean height of the tangent line of the superior margin of the contralateral femoral neck (19.4 mm). Conclusions Pertrochanteric fractures with the proximal starting point lower than the mirror position of the tangent line to the superior margin of the contralateral femoral neck have a higher risk of intraoperative lateral wall fractures during cephalomedullary nailing.

A novel multistage air-gap diffusion distillation (MS-AGDD) system powered by low-grade sensible heat (LGSH) was proposed for fully recovering heat from LGSH to produce freshwater. The effect of operating parameter variations on the system performances was investigated theoretically based on the e-NTU model for AGDD. The operating parameters include the hot water inlet temperature ( T hs in ), the feed seawater flowrate ( V c , n in ), salinity ( S c , n in ) and temperature ( T c , n in ), the temperature differences at the hot end of heat exchanger ( Δ t h ) and at the cold end of coolers ( Δ t c ). Results showed that under the given structure and size parameters of the system and the operating conditions, the variation of T hs in , V c , n in or Δ t h affected the system performances significantly, but the variation of S c , n in or Δ t c affected those relatively less. The total freshwater yield and the recovered heat from the hot water enlarged with the increase of T hs in or V c , n in , but they decreased with the increase of Δ t h . The gained out ratio (GOR) of the system increased with the increase of T hs in , but it decreased with the increase of V c , n in or Δ t h . The irreversibility of the system increased with the increase of T hs in or Δ t h , but it decreased with the increase of T c , n in or V c , n in .

Reverse electrodialysis (RED) is a promising technology to extract electric energy from salinity gradient energy (SGE). Through being combined with multi-effect distillation (MED) where low grade heat is converted into SGE, a closed-loop system named hybrid MED-RED power generation system was presented. In this study, a detailed thermodynamic analysis for the system was performed to investigate how the relevant operation and structure parameters influence on the performance of the system. When hot and cooling water temperatures were respectively 80 °C and 20 °C and a six-effect distiller was applied, the energy conversion efficiency of the system reached 0.76% under the given operation conditions. The results showed that the increase of the hot water inlet temperature, initial salt molarity of brackish solution and effect number of MED all would positively influence on the performance of the system. The energy conversion efficiency of the system could be promoted to 0.85% when the hot water inlet temperature and initial salt molarity of brackish solution were 95 °C and 3.75 mol·kg−1 respectively. In addition, under the given operation conditions, when the effect number of MED reached 10, the energy conversion efficiency of the system could reach to 1.01%.

Salinity gradient energy exists between the concentrated and diluted electrolyte solutions, which can be converted to the electromotive force of a reverse electrodialysis (RED) cell. The waste solution is regenerable to restore the initial concentrations by absorbing thermal energy. The energy conversion efficiency of such a heat−to−power system is strongly influenced by the working solutions. The potassium acetate−methanol−water solution is proposed and assessed as the new candidate working fluid for the RED power system in this study firstly. The electrical conductivity of this ternary solution is fully measured and found to be influenced by the solution concentration, temperature and solvent composition. The maximum measured electrical conductivity value is 144.0 mS cm−1 at 6.0 mol kg−1 at 313.15 K. Furtherly, the electrical convertibility of potassium acetate−methanol−water is tested under the varying conditions freshly. The RED cell performances are influenced by the concentrations of the feeding dilute solution (recommendation: 0.02 mol kg−1), concentrated solution (optimum: 6.0 mol kg−1), solution flow rate (approximately 1.5 cm s−1), solution temperature (20 K higher than the environmental temperature), solvent composition (aqueous methanol solvent is preferred), and width of solution compartment (100 μm is suitable). Potassium acetate−methanol−water is a competitive new working fluid with the comprehensive advantages in thermodynamic and electrochemical properties.

Reverse electrodialysis (RED) is a promising technology that directly converts salinity gradient energy into electrical energy through the directional permeation of ions across the ion exchange membranes (IEMs). Fundamental understanding of the multi-physical RED process requires a reliable description of all the related phenomena involved in the process. In this work, a two-dimensional RED model based on the Nernst-Planck framework was developed. The fluid dynamics and ion transport were modelled in a full-length cell pair domain by employing the continuity, Navier-Stokes and Nernst-Planck equations complemented by the Donnan exclusion theory and local electroneutrality. The experimentally inaccessible IEM diffusion coefficients were analytically determined using the counterion condensation theory incorporating the tortuosity effect. A numerical simulation was carried out using the developed model. The solution velocity, ion concentration and electric fields were obtained and the characteristics of ion transport were analyzed. The effects of solution inlet velocity, IEM fixed charge concentration and cell pair length on RED performance were investigated and the mechanisms governing the variations of performance parameters were revealed based on ion transport. The present model contributes to a clearer understanding of the connection between the ion transport behavior and the stack performance.

Reverse electrodialysis (RED) technology is a direct and effective technology for power generation by harvesting salinity gradient energy (SGE). The output current is one of the key operating parameters to control the power output of a RED stack. This research investigates the specific effect of the current-induced ion transfer on each electrical resistance component of the RED stack. The results showed that the internal resistance of the RED stack decreases with the increase of the current, because larger ion transfer induced by larger current would initiate the variation of concentrations of the feeding concentrated and diluted solutions along the flow path. It is worth highlighting that the ohmic resistance of the diluted solution component takes the dominant proportion in the total ohmic resistance of a RED stack, which decreases significantly with the increase of current. The non-ohmic resistance also decreases with the current increases. Therefore, the internal resistance of RED stack depends on the current. Moreover, it is found that the polarization curve and power density curve can be in good accordance with the experimental data if the influence of current on internal resistance is taken into consideration. The energy efficiency increases first and decreases with the current increase. The maximal energy efficiency of 3.4% was achieved when the RED stack operated in the maximum power density of 3.67 W/m2 at the current density of 44.9 A/m2. The coulombic efficiency increases with the increase of the current. The residual ratio of the SGE in effluent decreases with the increase of the current.

To develop the suitable and cost-competitive membranes, the cross-linked poly(vinyl alcohol)/sulfosuccinic acid (PVA/SSA) cation exchange membranes (CEMs) were prepared and their potential as feasible reverse electro-dialysis (RED) CEMs was evaluated experimentally. Results proved after the thermal treatment at the cross-linking temperature of 120 ℃, the custom-made membranes exhibited the most favorable electrochemical characteristics. The PVA/SSA CEM with 20 wt% SSA in polymer blends had more advantages in the RED process because of the excellent mechanical and transport properties. Furthermore, the results presented that the stack with the custom-made CEMs with 20 wt% SSA content had similar maximum power density (1.022 W m−2) to that with the excellent commercial CEMs (Selemion CMV) (1.072 W m−2) in the same RED configuration, although the PVA/SSA CEMs possessed the relatively low permselectivity. Besides, the PVA CEMs had the lower stack resistance and non-ohmic resistance compared with the Selemion CMV CEMs.

Fluid flow and heat transfer in a solar air heater roughened with staggered multiple V-shaped ribs on the absorber plate were investigated numerically. Three dimensional simulations were performed for different rib geometries with varying stagger distance; rib height, pitch, and attack angle; and Reynolds number. Staggered multiple V-shaped ribs provide better heat transfer than the corresponding inline arrangement, with maximum enhancement 26% and 18% for average Nusselt number and thermohydraulic performance factor, respectively. Streamwise primary vortex with inter-rib subsidiary vortex is still the basic flow structure for the staggered ribs, similar to the inline case. The gap flow induces two competing effects on heat transfer, enhancing heat transfer efficiency maximally at the optimum stagger distance. Maximum thermohydraulic performance factor for the staggered ribs was 2.43 in the range of parameters studied.

It is a great challenge to cure symptomatic lesions and considerable defects of hyaline cartilage due to its complex structure and poor self-repair capacity. If left untreated, unmatured degeneration will cause significant complications. Surgical intervention to repair cartilage may prevent progressive joint degeneration. A series of surgical techniques, including biological augmentation, microfracture and bone marrow stimulation, autologous chondrocyte implantation (ACI), and allogenic and autogenic chondral/osteochondral transplantation, have been used for various indications. However, the limited repairing capacity and the potential pitfalls of these techniques cannot be ignored. Increasing evidence has shown promising outcomes from ACI and cartilage transplantation. Nevertheless, the morbidity of autologous donor sites and limited resource of allogeneic bone have considerably restricted the wide application of these surgical techniques. Costal cartilage, which preserves permanent chondrocytes and the natural osteochondral junction, is an ideal candidate for the restoration of cartilage defects. Several in vitro and in vivo studies have shown good performance of costal cartilage transplantation. Although costal cartilage is a classic donor in plastic and cosmetic surgery, it is rarely used in skeletal cartilage restoration. In this review, we introduce the fundamental properties of costal cartilage and summarize costa-derived chondrocyte implantation and costal chondral/osteochondral transplantation. We will also discuss the pitfalls and pearls of costal cartilage transplantation. Costal chondral/osteochondral transplantation and costa-based chondrocytotherapy might be up-and-coming surgical techniques for recalcitrant cartilage lesions.

The effectiveness-number of transfer units (e-NTU) method was used to develop the heat and mass transfer model of air-gap diffusion distillation (AGDD). In this model, the latent heat transfer of vapor in air-gap was regarded as an equivalent convective heat transfer to make a relationship with NTU. Compared with the full numerical model developed in our previous work, the new model was simple and performing with dramatic high computational efficiency. The accuracy of the model was as well as the full numerical model. The influences of structure and operation parameters on the performances of AGDD system were discussed furtherly by employing the model. Results shown that the air-gap height, the inlet temperature and feed flow rate of hot stream could be regarded as the strong parameters effected significantly on the performances of the system in comparison with the air-gap thickness and inlet temperature and salt concentration of cold stream. Therefore, these strong parameters should be considered firstly for improving the heat and mass transfer of AGDD.

A visual experimental research was conducted to investigate the flow patterns and absorption height (AH) in a vertical bubble absorption tube employing R124-NMP as working fluid. The effects of various operation parameters, solution inlet mass concentration, temperature and volumetric flow rate, vapor volumetric flow rate, absorption pressure and orifice diameter, on the flow patterns and AH were examined. The key operation parameters were all converted into dimensionless numbers and the influences of dimensionless operation parameters on dimensionless absorption height (DAH) were studied. The results showed that the AH increases with increasing solution inlet mass concentration and temperature, vapor volumetric flow rate and orifice diameter and decreases with increasing solution volumetric flow rate and absorption pressure. DAH exhibits nearly linear change along with dimensionless operation parameters. Comparisons between the flow patterns and AH of R124-NMP and R124-DMAC were performed. The compared results illustrated that employing R124-NMP as working fluid can shrink the vertical bubble absorber size. Finally, the experimental correlations of AH and DAH were developed with ±20% and ±15% error bands, respectively. The correlation of DAH maybe used to predict absorption height in the design of bubble absorber employing refrigerant-organic absorbent as working fluid.

To assess the mid-term effectiveness of arthroscopic surgery in treatment of femoroacetabular impingement (FAI).Between July 2014 and December 2015, 131 patients (132 hips) with FAI were enrolled in this study. There were 68 males and 63 females with an average age of 42.5 years (range, 17-68 years). The FAI was located at left hip in 72 cases, right hip in 58 cases, and bilateral hips in 1 case. The mean disease duration was 35 months (range, 3-120 months). Under arthroscopy, the femoral neck osteoplasty and/or acetabular rim trimming were performed, then the torn labrum was repaired. At the same time, the iliopsoas tendon was divided and the torn round ligament was debrided. The effectiveness was assessed by the visual analogue scale (VAS) and the Harris hip score (HHS).After operation, the perineum nerve palsy and numbness of dorsal feet occurred in 2 cases and 3 cases, respectively. There was no other complication. All patients were followed up 20-36 months (mean, 27.7 months). There were significant differences in the VAS scores and HHS scores between pre-operation, post-operative 3 months, and the last follow-up (Arthroscopic labral repair and osteoplasty is an effective and safe management for FAI in the mid-term follow-up.总结关节镜下手术治疗股骨髋臼撞击征（femoroacetabular impingement，FAI）的中期疗效。.回顾分析 2014 年 7 月—2015 年 12 月收治并符合选择标准的 131 例（132 髋）FAI 患者临床资料。男 68 例，女 63 例；年龄 17～68 岁，平均 42.5 岁。左髋 72 例，右髋 58 例；双髋 1 例。病程 3～120 个月，平均 35 个月。关节镜下行髋臼和/或股骨头颈成形、盂唇修补，同时松解粘连的髂腰肌腱、清理撕裂的圆韧带。采用疼痛视觉模拟评分（VAS）及髋关节 Harris 评分（HHS）评价疗效。.术后除 2 例出现阴部神经麻痹、3 例足背麻木外，无其他相关并发症发生。患者均获随访，随访时间 20～36 个月，平均 27.7 个月。术后 3 个月及末次随访时 VAS 评分及 HHS 评分与术前比较，差异均有统计学意义（关节镜下手术治疗 FAI，在行髋臼和/或股骨头颈成形的同时修补撕裂盂唇，中期疗效满意，是一种安全、有效、微创的治疗方法。.

A numerical investigation of heat transfer and fluid flow characteristics in a solar air heater duct having multi V-shaped ribs on the absorber plate is presented in this study. Three-dimensional simulations are conducted using the ANSYS FLUENT code and the Renormalization-group k–e turbulence model. The computations are performed for different rib geometries with a varying spanwise V-rib number, relative rib pitch, relative rib height, and angle of attack, and for different Reynolds numbers. The effects of the rib geometrical parameters on the Nusselt number, friction factor, and flow structure are obtained and analyzed. Clearly, the multi V-shaped ribs greatly enhanced the heat transfer. The maximum value of the thermal performance parameter was found to be 1.93 for the range of parameters investigated. The multi V-shaped ribs generate streamwise helical vortex flows, which promote the fluid mixing between the colder mainstream fluid and the warmer fluid near the absorber wall. In addition, the moving subsidiary vortex structure at the inter-rib region further enhances the local fluid mixing.

Femoral neck nonunion (FNN) is a potential complication in patients with displaced femoral neck fractures, occurring in 33%. This may lead to early hip dysfunction or arthroplasty. Combination of modified free vascularized fibular grafting (FVFG) and a reverse LISS may provide a reasonable means to salvage a painless, functional and native hip. Between August 2010 and August 2012, sixteen patients with femoral neck nonunion were treated with a combined procedure involving modified free vascularized fibular grafting and a reverse LISS. The average age of them is 20.3 years (range 12.0–28.0 years). After removing old implants, the nonunion site was debrided, reduced and fixed with a LISS. The fibular grafts were compacted into a trough in the femoral neck. The Harris Hip score system was used to assess hip function and anteroposterior and frog-lateral hip roentgenograms were used to evaluate bone healing. All femoral neck nonunion healed without severe complications. The mean follow-up time was 32.9 months (range 23.0–47.0 months) and the average union time was 7.6 months (range 5.0–10.0 months). All coxa vara deformities and retroversions of the femoral head were corrected. The Harris hip scores (HHS) were improved 36.6 points on average (59.6 points preoperatively to 96.2 points postoperatively). No incidences of osteonecrosis of the femoral head were observed. The combined modified FVFG and reverse LISS plating is a suitable procedure for the management of femoral neck nonunion in patients younger than 30 years, especially for those patients with a revision history.

Background Biochemical substances relating to renal and hepatic function are influenced not only by individual factors such as gender, lifestyle, and age but also by ecological factors, such as altitude, climate, and ethnic background. The purpose of the present study was to establish reference intervals for 16 biochemical substances relating to renal and hepatic function in healthy Chinese adults. Methods A total of 2,405 apparently healthy individuals (18–77 years of age) were chosen as reference individuals in the present study. The 16 biochemical substances relating to renal and hepatic function were analyzed using a HITACHI RL7600 analyzer. The reference intervals were established using nonparametric methods to estimate the 2.5 and 97.5 percentiles of the distribution as the lower and the upper limits, respectively. Results Age- and gender-appropriate reference intervals were established for some biochemical substances relating to renal and hepatic function in healthy Chinese adults. Conclusion The reference intervals established in this study can provide a useful clinical tool for the assessment of the kidney and liver damage. In addition, the established reference intervals can be adopted in other clinical laboratories after further validation.

Mobile ad hoc networks (MANETs) become more and more popular and significant in many fields. However, the important applications of MANETs make them very attractive to attackers. The deployment scenarios, the functionality requirements, and the limited capabilities of these types of networks make them vulnerable to a large group of attacks, e.g., blackhole attacks. In this paper, we propose a cluster-based scheme for the purpose of preventing blackhole attacks in MANETs. In our scheme, we firstly present a novel algorithm that employs a powerful analytic hierarchy process (AHP) methodology to elect clusterheads (CHs). Then CHs are required to implement the blackhole attacks prevention scheme to not only detect the existence of blackhole attacks but also identify the blackhole nodes. Simulation results show that our scheme is feasible and efficient in preventing blackhole attacks.

The goal for treatment of osteonecrosis of the femoral head (ONFH) is to relieve pain, preserve the contour of the femoral head, and delay the need for total hip arthroplasty. The free vascularized fibular grafting (FVFG) has been shown to support the subchondral architecture as well as restore local circulation for the necrotic femoral head in treatment of ONFH. This report aimed to present the clinical results of the use of a modified surgical technique of FVFG for treatment of ONFH. Four hundred and seven patients with 578 hips of ONFH were included. The patients' average age was 36.7 years old (ranging 19-55 years old). The disease was staged from II to V based on the Steinberg classification system. By the modified procedure, the vascularized fibular graft was harvested via a lateral incision with fibular osteotomy prior to the exposure of the vascular pedicle, and the removal of necrotic tissue and inset of graft were performed through an anterior approach. The operative time averaged 90 min for unilateral ONFH (ranging 75-110 min) and 190 min for simultaneous treatment of bilateral ONFH (ranging 160-230 min). The average length of follow-up was 5.0 years (ranging 3-10 years). The complications included one infection in one case, temporary loss of sensation of the thigh in eleven cases, and restricted motion of the great toe in nine cases. The Harris hip score of patients improved from 65.0 to 86.9 on average. Radiographic evaluation showed no changes in 331 hips (57.3%), improvement in 195 hips (33.7%) and necrosis progression in 52 hips (9.0%). Twenty-three hips (4.0%) in 20 patients had total hip arthroplasty during the period. These results show that the modified technique of the use of FVFG for treatment of ONFH yields similar postoperative results in comparison to the traditional method.

While it has been proved that centrifugal conditions for pure platelet-rich plasma (P-PRP) preparation influence the cellular composition of P-PRP obtained, the optimal centrifugal conditions to prepare P-PRP have not yet been identified. In the present study, platelet-containing plasma (PCP) was prepared with the first-spin of different double-spin methods and P-PRP was prepared with different double-spin methods. Whole-blood analysis was performed to evaluate the cellular composition of PCP and P-PRP. The basal and ADP-induced CD62P expression rates of platelets were assessed by flow cytometry to evaluate the function of platelets in PCP and P-PRP. Enzyme-linked immune sorbent assay was performed to quantify interleukin-1β, tumor necrosis factor-α, platelet-derived growth factor AB and transforming growth factor β1 concentrations of PCP and P-PRP. Correlations between the cellular characteristics and cytokine concentrations of P-PRP were analyzed by Pearson correlation analysis. Effects of P-PRP on the proliferation, survival and migration of human bone marrow-derived mesenchymal stem cells and human articular chondrocytes were evaluated by a Cell Counting Kit-8 assay, live/dead staining and Transwell assay, respectively. The results showed that centrifugation at 160 × g for 10 min and 250 × g for 15 min successively captured and concentrated platelets and growth factors significantly more efficiently with preservation of platelet function compared with other conditions (P0.05) and the maximization of platelet concentration, platelet enrichment factor, platelet capture efficiency and platelet function resulted in the maximization of growth factor concentrations in P-PRP obtained using the optimal conditions (P0.05). Therefore, centrifugation at 160 × g for 10 min and 250 × g for 15 min successively with removal of the buffy coat as a crucial step may provide an optimal preparation system of P-PRP for clinical application.