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Sodium metal batteries have been emerging as promising candidates for post-Li battery systems owing to the natural abundance, low costs, and high energy density of Na metal. However, exploiting an Na metal anode is accompanied by uncontrolled Na electrodeposition, particularly concerning dendrite growth, hampering practical Na metal battery applications. Herein, we propose sodiophilic gel polymer electrolytes with a porosity-gradient Janus structure to alleviate Na dendrite growth. Tethering only 1.1 mol % sodiophilic poly(ethylene glycol) to poly(vinylidene fluoride

Transforming how plastics are made, unmade, and remade through innovative research and diverse partnerships that together foster environmental stewardship is critically important to a sustainable future. Designing, preparing, and implementing polymers derived from renewable resources for a wide range of advanced applications that promote future economic development, energy efficiency, and environmental sustainability are all central to these efforts. In this

There have been some reports of gross trunnion failure (GTF) in total hip arthroplasty. Here, we report a case of GTF 19 years after bipolar hemiarthroplasty using a 28-mm head with a 14/16 taper bore. Compared to other GTF reports, the current case had some unusual aspects: bipolar hemiarthroplasty, 28-mm head, relatively late-onset, and no apparent findings of metallosis though a severe one was evident. A Computed tomography scout view provided valuable information in evaluating polyethylene, metal head, and neck inside the bipolar cup. The current report suggests a need for concerned regarding short trunnion length which may be associated with GTF.

Significant research effort has been directed toward the development of sustainable plastics that are high-performance, bioderived, and/or degrade into nontoxic byproducts in natural or engineered environments (i.e., industrial composting facilities). We report the low cytotoxicity of poly(γ-methyl-e-caprolactone) (PMCL)-based materials and the hydrolysis product of PMCL, sodium 6-hydroxy-4-methylcaproate. The concentration of sodium 6-hydroxy-4-methylcaproate that leads to 50% cell death (TD₅₀) is 179 mM, a value that is similar to that of the hydrolysis product of polycaprolactone and higher than that of the hydrolysis product of polylactide. We also report the degradability of two PMCL materials with different architectures (cross-linked and linear triblock polymers) under simulated industrial composting conditions. These materials reached high degrees of carbon mineralization (>85%) over the course of 120 days as monitored by CO₂ evolution. Finally, we examined the industrial compostability of a new aromatic polyester, poly(salicylic methyl glycolide). This material reached 89% carbon mineralization after 120 days, an important finding given the recalcitrance toward degradation of ubiquitous aromatic polyesters.

Mechanisms of ceramic liner fractures have not yet been fully elucidated. Impingement between a stem and ceramic liner is a proposed cause of ceramic liner fractures. We experienced a case of ceramic liner fracture caused by direct impingement between the stem shoulder and the ceramic liner. This type of impingement, unlike impingements with a stem neck, has not been previously reported. While we assume that certain characteristics of the stem contributed to the impingement, we report this case to note that caution may be needed when using certain stem designs.

Pressure sensitive adhesives (PSAs) are widely used in a variety of applications (e.g., sticky note and packing tape). As for most commercial polymer products, current PSA materials are primarily d...

Plastic pollution is one of the most pressing global environmental issues we face today, in part due to the continued rise in production and use of disposable plastic products. Polyolefins and polyesters are two of the most prevalent polymers in the world accounting for ∼80% of total nonfiber plastic production. Recycling, despite being intrinsically environmentally friendly and sometimes economically viable, remains at a surprisingly low level (

Polyesters constitute nearly 10% of the global plastic market, but most are essentially non-degradable under ambient conditions or in engineered environments. A range of degradable polyesters have been developed as more sustainable alternatives; however, limitations of practical degradability and scalability have hindered their viability. Here, we utilized transesterification approaches, including in situ polymerization-transesterification, between a salicylate and a polyester to incorporate salicylate units into commercial polyester backbones. The strategy is scalable and practically relevant given that high molar mass polymers can be obtained from melt-processing of commercial polyesters using common compounders or extruders. Polylactide containing sparse salicylate moieties shows enhanced hydrolytic degradability in aqueous buffer, seawater, and alkaline solutions without sacrificing the thermal, mechanical, and O2 barrier properties of the parent material. Additionally, salicylate sequences were incorporated into polycaprolactone and a derivative of poly(ethylene terephthalate), and those modified polymers also exhibited facile degradation behavior in alkaline solution, further expanding the scope of this approach. This work provides insights and direction for the development of high-performance yet more sustainable and degradable alternatives to conventional polyesters.

Polyesters constitute around 10% of the global plastic market with aromatic polyesters, such as poly(ethylene terephthalate) (PET), being the most prevalent because of their attractive properties. As for most commercial plastics, polyesters are primarily derived from fossil resources and are not readily degradable, which raises a number of sustainability concerns. Designing polymers with competitive properties from sustainable feedstocks that rapidly degrade under mild conditions is an attractive strategy for addressing the current plastic waste problem. Here, the detailed synthesis and characterization of degradable, high molar mass aromatic polyesters derived from salicylic acid, poly(salicylic glycolide) (PSG), and poly(salicylic methyl glycolide) (PSMG) are described. The synthesis of polymers was investigated through mechanistic experiments and complementary computational studies. The glass transition temperature (

Poly(phenylene sulfide) (PPS) is an attractive polymer in engineering plastics because of its high mechanical strength and thermal stability. Herein, poly(phenylene sulfide)/nylon 6 grafted graphene oxide (PPS/NGO) nanocomposites were prepared by micro-compounding, where NGO is prepared via ring-opening polymerization of e-caprolactam on the graphene oxide (GO), which has carboxylic acid groups that can act as an initiator. Since nylon 6 is known to be able to blend with commercial PPS, nylon 6 moiety in NGO can increase mechanical properties of PPS, especially by forming PPS/NGO nanocomposites with improved toughness. Moreover, graphene nanosheets can provide improved mechanical strength and thermal stability because of their mechanically reinforcing and thermal barrier effects. For example, if a PPS/NGO nanocomposite with 0.03 wt% of NGO was prepared, the tensile strength and elongation at break values increased by 32% and 30%, respectively, compared to neat PPS. Also, the thermal decomposition temperature for 5% weight loss increased from 481 to 488 °C, indicating the improved thermal stability. These improved properties can be attributed to the well-dispersed NGO in the PPS matrix, as confirmed by the morphological studies using SEM and EDS mapping.

We investigated the lateral distribution of the equilibrium carrier concentration (n0) along the channel and the effects of channel length (L) on the source-drain series resistance (Rext) in the top-gate self-aligned (TG-SA) coplanar structure amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs). The lateral distribution of n0 across the channel was extracted using the paired gate-to-source voltage (VGS)-based transmission line method and the temperature-dependent transfer characteristics obtained from the TFTs with different Ls. n0 abruptly decreased with an increase in the distance from the channel edge near the source/drain junctions; however, much smaller gradient of n0 was observed in the region near the middle of the channel. The effect of L on the Rext in the TG-SA coplanar a-IGZO TFT was investigated by applying the drain current-conductance method to the TFTs with various Ls. The increase of Rext was clearly observed with an increase in L especially at low VGSs, which was possibly attributed to the enhanced carrier diffusion near the source/drain junctions due to the larger gradient of the carrier concentration in the longer channel devices. Because the lateral carrier diffusion and the relatively high Rext are the critical issues in the TG-SA coplanar structure-based oxide TFTs, the results in this work are expected to be useful in further improving the electrical performance and uniformity of the TG-SA coplanar structure oxide TFTs.

Metal batteries have been emerging as next-generation battery systems by virtue of ultrahigh theoretical specific capacities and low reduction potentials of metallic anodes. However, significant concerns regarding the uncontrolled metallic dendrite growth accompanied by safety hazards and short lifespan have impeded practical applications of metal batteries. Although a great deal of effort has been pursued to highlight the thermodynamic origin of dendrite growth and a variety of experimental methodologies for dendrite suppression, the roles of polymer materials in suppressing the dendrite growth have been underestimated. This review aims to give a state-of-the-art overview of contemporary dendrite-suppressing polymer materials from the electro-chemo-mechanical viewpoint of macromolecular design, including i) homogeneous distribution of metal ion flux, ii) mechanical blocking of metal dendrites, iii) tailoring polymer structures, and iv) modulating the physical configuration of polymer membranes. Judiciously tailoring electro-chemo-mechanical properties of polymer materials provides virtually unlimited opportunities to afford safe and high-performance metal battery systems by resolving problematic dendrite issues. Transforming these rational design strategies into building dendrite-suppressing polymer materials and exploiting them towards polymer electrolytes, separators, and coating materials hold the key to realizing safe, dendrite-free, and long-lasting metal battery systems.

Incomplete fractures are assumed to occur in the intertrochanteric area as fractures at other sites, but reports of incomplete intertrochanteric fractures (IIFs) are rare. In 1999, Schultz et al. defined isolated greater trochanter fractures (GTFs) as IIFs when intertrochanteric extension is observed on magnetic resonance (MR) images. On multiplanar reformation computed tomography (MPR CT) images acquired for further study of apparently isolated GTFs, we noted incomplete cortical breakage in the intertrochanteric area. We then found that the fracture line was incomplete on plain radiographs in some intertrochanteric fractures. We evaluated IIFs and apparently isolated GTFs using MPR CT and analyzed the fracture patterns of IIFs that were confirmed using MPR CT.Between February 2006 and June 2019, 36 cases of IIF were detected using MPR CT in 36 patients. They were 17 women and 19 men with a mean age of 74.7 years (range, 26-94 years). Plain radiographs and MPR CT images were evaluated by two experienced orthopedic surgeons. In addition, MR imaging was performed in 5 cases.Plain radiographs showed no evidence of fracture in 2 cases, isolated GTF in 7 cases, and IIF in 27 cases. In all cases, incomplete cortical breakage in the intertrochanteric area was confirmed on MPR CT images. Cortical breakage was located in the anterior portion of the intertrochanteric area, whereas the posterior portion remained intact in all cases. The detection rate of cortical breakage was higher on coronal or sagittal images than that on axial images. On MR images of 5 cases, intertrochanteric extensions were found in the medullary space. All extensions originated in the greater trochanter area and extended anteriorly in the axial plane and inferomedially in the coronal plane. On the T1-weighted mid-coronal image, the extension reached or passed the midline in 3 cases, and cortical breakage was detected in only 2 cases.In all cases of IIF, cortical breakage was detected in the anterior portion of the proximal femur, leaving the posterior cortex intact. This finding is notably different from that of intertrochanteric extension (from posterior to anterior) detected on MR images of isolated GTFs.

Poly(ethylene terephthalate) (PET) is one of the most prevalent polymers in the world due to its combined thermal, mechanical, and gas barrier attributes. Blending PET with other polymers is an appealing strategy to further tailor properties to meet the needs of an even more diverse range of applications. Most blends with PET are macrophase-separated; only a few miscible systems have been reported. Here, the miscibility of the aromatic polyesters poly(salicylic glycolide) (PSG) and poly(salicylic methyl glycolide) (PSMG) with PET is described. Both PSG and PSMG have similar chemical structures to PET but are derived from sustainable resources and readily degradable. This study suggests that they are fully miscible with PET over the entire composition range, which is attributed to favorable interactions with PET. Negative polymer-polymer interaction parameters (χ) were determined using Flory-Huggins theory to describe melting temperature variations in the blends. In addition, the PET blends showed mechanical properties that are intermediate between the two homopolymers.

Background It is assumed that impingement between the ceramic liner and the stem increases the possibility of a liner fracture in total hip arthroplasty with a ceramic-on-ceramic bearing. The purpose of this study was to analyze the pattern of the impingement by evaluating the notches (U-shaped indented wear scars engraved on the stem) on radiographs to determine when and where impingement develops and to analyze the factors affecting its occurrence. Methods Among the primary total hip arthroplasty cases using a ceramic-on-ceramic bearing performed from November 1997 to December 2003, 244 cases of 197 patients (123 male patients and 74 female patients) that had follow-up of ≥15 years were included. All of the radiographs were examined with special regard to the notches and the cup positions. Results Notches were detected at 77 sites of 57 cases (23.4%) for the first time between 8 months and 14.8 years after the surgical procedure. They were located on the neck or the shoulder of the stem. Shoulder notches were detected only in the cases with a short-neck head. Shoulder notches were found in 29 cases (20.0% of short-neck cases). Cup inclination was lower (p = 0.01) and anteversion was higher (p = 0.01) in the group with notches than the group without notches. There were 5 cases of ceramic head fracture. One of them experienced another ceramic liner fracture, assumed to be caused by prosthetic shoulder impingement, after the revision surgical procedure. Conclusions The results of this study suggest that impingement between the stem and the ceramic liner occurs in a considerable proportion of patients who underwent total hip arthroplasty not only on the neck but also on the shoulder of the stem. Forceful and abrupt impingement on the stem shoulder can cause ceramic liner fracture. Impingement between the stem shoulder and the ceramic liner should be considered in designing a stem. It seems to be prudent to recommend that patients avoid squatting or sitting cross-legged on the floor as much as possible. Level of evidence Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Background: Total hip arthroplasty (THA) with a proximally coated single-wedge (PSW) cementless stem had been generally considered not to be suitable for Dorr Type C femurs. This study compares the long term outcomes of PSW stem according to the type of proximal femoral geometry. Materials and Methods: 307 primary THAs in 247 patients were performed with PSW cementless stem and followed up for over 10 years in this retrospective study. According to Dorr's criteria, 89 femurs were classified as Type A, 156 as Type B, and 62 as Type C. They were followed up for an average of 13.2 years (range 10.0–17.3 years). All the hips were evaluated clinically and radiologically. Results: There was no significant difference in stem survivorship and clinical outcomes including the incidence of thigh pain and the mean postoperative Harris hip score (HHS) in all three groups. No significant differences were observed in osteolysis, pedestal formation, or cortical hypertrophy among the groups. Radiolucent lines

Purpose This study presents the clinical and radiological outcomes of cementless total hip arthroplasty using the COREN hip system after a minimum duration of follow-up of 5 years. Materials and Methods We evaluated the results of a consecutive series of the first 200 primary total hip arthroplasties that had been performed in our hospital in 169 patients between February 2007 and April 2011. Six patients (6 hips) had died within 5 years, and 12 patients (13 hips) had been lost to follow-up, leaving a total of 151 patients (181 hips) available for the study. All patients were evaluated clinically and radiologically with special attention to thigh pain, implant fixation, radiolucent line and osteolysis around implants. Results The mean Harris hip score improved from 59.4 preoperatively to 97.2 postoperatively. No patient complained of thigh pain. All implants demonstrated radiographic evidence of stable fixation by bone ingrowth without any change in position. No implant was loose radiographically or was revised. Eleven hips (7.7%) had a radiolucent line around the femoral stem. Focal osteolytic area was detected in 3 cases (2.1%). An osteolytic lesion was stabilized in 1 case and further observation was needed in 2 cases in which the lesions were detected several years after surgery. Stress shielding was observed in 80.3% of cases (first degree, 35.9%; second degree, 44.4%); there were no cases of third or fourth degree stress shielding. One case was complicated by bacterial infection and repeated dislocation. Conclusion Mid-term results of total hip arthroplasty using the COREN hip system are very encouraging clinically and radiologically.

Most isolated greater trochanter (IGT) fractures are treated conservatively. However, some require surgical fixation although indications for surgery have not yet been established. Many surgeons perform surgical fixation when the intertrochanteric extension crosses the midline on magnetic resonance (MR) images. Nevertheless, for mechanical strength, cortical bone integrity is more important than that of intramedullary cancellous trabeculae. We retrospectively evaluated the clinical usefulness of multiplanar reformation computed tomography (MPR CT) in determining treatment strategies for IGT fractures.We evaluated 99 cases of suspected IGT fractures between October 2004 and December 2019. They were 66 women and 33 men with a mean age of 77 years. The mean follow-up period was 34 months. Most patients were evaluated with plain radiographs, followed by additional imaging study via MPR CT in 65 cases, magnetic resonance imaging (MRI) in 5 cases, and both in 17 cases. Typically, fractures were fixed surgically when a cortical breakage was detected in the intertrochanteric area on MPR CT, while fractures without evidence of cortical breakage on MPR CT were treated conservatively.In 13 out of 82 cases evaluated by MPR CT, incomplete cortical breakage in the intertrochanteric area was detected, of which 10 were treated surgically. The remaining 3 cases were treated conservatively due to patient's refusal, poor medical condition, and failure to detect breakage. Of 69 cases without cortical breakage, 61 cases were successfully treated conservatively. Among the 17 cases evaluated by both MPR CT and MRI, cortical breakage was detected in 3, of which the intertrochanteric extension crossed the midline on the MR image only in 1 case. Of the remaining 14 cases without breakage, the intertrochanteric extension crossed the midline in 5. Among these 5 cases, 3 were treated conservatively.The results suggest that MPR CT is a useful imaging modality for further evaluation of IGT fractures. It was especially valuable in evaluating cortical bone integrity, which may be more critical for fracture stability.

The current trend of using short femoral stems in total hip arthroplasty (THA) is associated with angular deviation of the femoral stem towards the native femoral axis. The purpose of this study was to compare the difference in stem tilt angle between two different stems with a similar design except for the stem length.This is a retrospective review of 66 patients who underwent primary THA between April 2012 and May 2016, using a trans-gluteal direct lateral approach by a single surgeon. We evaluated the femoral stem tilt angle in both the coronal and sagittal planes and performed multivariate logistic regression analysis to evaluate possible risk factors. We also simulated the range of motion (ROM) of the hip joint using three-dimensional computer-aided design software (SolidWorks, 2016) to examine the clinical significance of femoral stem tilt.The mean coronal tilt angle was 1.8° ± 1.0° in the conventional stem group and 1.6° ± 1.1° in the short stem group, showing no statistically significant difference between the groups (Anterior femoral stem tilting in the sagittal plane was prominent when the shorter stem was used, and anterior tilting was responsible for decreased ROM in hip extension.

Carbon nanotube (CNT)-polyamide (PA) thin-film nanocomposite (TFN) reverse osmosis (RO) membranes have been highlighted due to their high water permeability. We evaluated the surface properties, membrane performance and fouling behavior of CNT-PA TFN RO membranes. The CNT-PA TFN RO membranes showed ∼30% enhanced water flux, which resulted in a lower energy consumption. The smoother surface of the CNT-PA TFN RO membranes led to less membrane fouling, while its biofouling resistance was insignificant due to less positioned CNTs on the membrane surface. These results provide important insights into the factors optimizing CNT-PA TFN RO membranes as a high performance RO membrane.

Solid polymer electrolytes (SPEs) based on polysiloxane having ion-conducting poly(ethylene oxide) (PEO) groups crosslinked with modified gallic acid from natural resources are prepared by thiol-ene click reaction for all-solid-state lithium metal battery applications. The effects of composition and crosslinking density on physical and electrochemical properties of the SPEs are systematically studied. The SPEs are found to be thermally and mechanically stable even at elevated temperature due to stable crosslinked polymer networks by modified gallic acid crosslinker. Furthermore, ionic conductivity of SPE based on 80 mol% of PEO group and 20 mol% of modified gallic acid crosslinker is found to be comparable to that of polymer electrolyte having a wax state. The formation and growth of lithium dendrites are effectively suppressed by the SPE due to its good compatibility with lithium metal anode and mechanical suppression effect. All-solid-state lithium metal battery is fabricated with SPE-integrated cathode and it is found that SPE exhibits superior cycle performance to conventional liquid electrolyte/separator system at 60 °C that is attributed to the good thermal stability and lithium dendrite-suppressing ability of the SPE.

Lithium-metal anode has fundamental problems concerning formation and growth of lithium dendrites, which prevents practical applications of next generation of high-capacity lithium-metal batteries. The synergistic combination of solid polymer electrolyte (SPE) crosslinked with naturally occurring terpenes and lithium-powder anode is promising solution to resolve the dendrite issues by substituting conventional liquid electrolyte/separator and lithium-foil anode system. A series of SPEs based on polysiloxane crosslinked with natural terpenes are prepared by facile thiol-ene click reaction under mild condition and the structural effect of terpene crosslinkers on electrochemical properties is studied. Lithium powder with large surface area is prepared by droplet emulsion technique (DET) and used as anode material. The effect of the physical state of electrolyte (solid/liquid) and morphology of lithium-metal anode (powder/foil) on dendrite growth behavior is systematically studied. The synergistic combination of SPE and lithium-powder anode suggests an effective solution to suppress the dendrite growth owing to the formation of a stable solid-electrolyte interface (SEI) layer and delocalized current density.

In this letter, we report on the charge transport mechanism in the p-type tin monoxide (SnO) thin-film transistors (TFTs) over a wide range of operation regimes and temperatures. From the temperature-dependent field-effect conductance measurements, the variable range hopping and the trap-limited band transport are considered as dominant charge transport mechanisms in the SnO TFT at temperatures below ~ 200 K (−73 °C) and above ~273 K (0 °C), respectively, in the subthreshold and transition regions. In the above-threshold region, the intrinsic field-effect mobility ( $\mu _{\mathsf {FEi}})$ decreases with an increase in temperature with a prefactor $\gamma \sim $ -0.36 in the $\mu _{\mathsf {FEi}}\sim {T}^{\gamma }$ law at temperatures ( ${T}\text{s}$ ) between RT and 353 K (80 °C). The observed temperature and gate overdrive voltage dependence of $\mu _{\mathsf {FEi}}$ suggests that the acoustic phonon scattering is the dominant physical mechanism limiting $\mu _{\mathsf {FEi}}$ in the p-type SnO TFT at realistic operating conditions [in the above-threshold region and at temperatures ranging from RT to 353 K (80 °C)].

In this letter, the energy distributions of the interface and bulk trap densities were separately determined in p-type tungsten diselenide (WSe2) thin-film transistors (TFTs) by measuring and analyzing the subthreshold transfer characteristics and space-charge-limited current under the flat-band condition at high drain-to-source voltages. From the experimental results, approximately 79% of the subgap trap states are attributed to the interface states at the valence band edge, which represents that the contribution of the interface trap states is more significant than that of the structural disorder-induced bulk trap states in the subgap density of states of the WSe2 TFT. Quantitative information about the separately determined interface and bulk trap densities presented in this letter will facilitate the further development of the fabrication processes to passivate the defect states at the interface in transition metal dichalcogenide-based TFTs, including WSe2 TFTs.

The multifunctional properties of 2D boron nitride nanoflakes (BNNFs) in gel polymer electrolytes (GPEs) are presented. A small addition (0.5 wt%) of BNNFs into the GPE substantially improves all the advantageous properties of the GPE including ionic conductivity, Li+ transference number, mechanical modulus, and dendrite-suppressing capability, thereby enabling high performance lithium metal batteries.

In this paper, we propose swimming pattern generator (SPG) which is mimicking locomotion of diving beetles with a view point of bimomimetics for legged underwater robots. Firstly, the locomotion of the diving beetle has been observed and classified through experiments with a motion capture system consist of a high-speed camera and imaging processing software Image J. Subsequently, we analyzed coordinated patterns of rhythmic movements of the diving beetle's leg and formulated equations by employing Fourier least mean square fitting method corresponding to the obtained raw data from the motion capture system. Based on this, control parameters have been determined by understating their characteristics through the procedure of comparing produced swimming trajectories according to varying their values to observed motions of the diving beetle. For extended research of SPG (ESPG) to reduce the number of the parameters, they are expressed in a parameter space based on correlations of individual parameters and a newly configured parameter space is proposed through underwater experiments. Consequently the number of parameters has been successfully reduced for effective real time application of SPG. Furthermore, a six legged underwater robot has been developed by considering structural advantages that diving beetles have for their effective swimming. Underwater experiments have been conducted to confirm the feasibility of the proposed idea.

In this letter, the carrier transport mechanism in a high-mobility zinc oxynitride (ZnON) thin-film transistor (TFT) is investigated by analyzing the gate bias and temperature dependence of conductance and intrinsic field-effect mobility ( $\mu _{\mathrm {FEi}})$ in the subthreshold and above-threshold regions, respectively. The measured drain currents increase with a temperature and show a thermally activated Arrhenius-like behavior in the subthreshold region. The experimental results are well explained using a Meyer–Neldel rule, which suggests that the trap-limited conduction is the dominant carrier transport mechanism in the ZnON TFT in the subthreshold region. The carrier transport mechanism in the ZnON TFT in the above-threshold region is investigated by examining the gate overdrive voltage ( $V_{\mathrm {OV}})$ and temperature dependence of $\mu _{\mathrm {FEi}}$ . $\mu _{\mathrm {FEi}}$ extracted from the ZnON TFT decreases with an increase in $V_{\mathrm {OV}}$ and temperature, which suggests that the phonon scattering is the most probable mechanism limiting $\mu _{\mathrm {FEi}}$ in the ZnON TFT in the above-threshold region.

s Pressure retarded osmosis (PRO) is an attractive process for capturing renewable energy that requires high-performance and fouling-resistant membranes. Herein, we report a novel surface coating method that increases the water flux and organic fouling resistance of PRO membranes. The support layer of a commercial TFC was coated with TiO2 nanoparticles (TNPs) via a sol-gel-derived spray coating method. This TNP coating imparted hydrophilic properties and a negative charge to the membrane surface. A TNP-coated membrane (TNP1.0) showed a 25% increase in water flux and a 50% decrease in reverse salt flux. The flux reduction of the TNP membrane was 32% less than that of a commercial TFC membrane in the presence of humic acid foulants. This suggests that a high-performance and fouling-resistant PRO membrane can be prepared using a TiO2 sol-gel-derived spray coating method.

Purpose: Atypical femoral fracture (AFF), periprosthetic femoral fracture (PPFF) and femoral nonunion (FNU) are recalcitrant challenges for orthopedic surgeons. Teriparatide (TPTD) had been demonstrated to have anabolic effects on bone in various studies. We postulated that adjuvant TPTD after operation would enhance biologic stimulation for bone formation. We investigated (1) whether the adjuvant TPTD could achieve satisfactory union rate of surgically challenging cases such as displaced AFF, PPFF and FNU; (2) whether the adjuvant TPTD could promote development of abundant callus after surgical fixation; (3) whether the adjuvant TPTD had medically serious adverse effects. Materials and Methods: Thirteen patients who agreed to off label use of TPTD in combination of operation were included in this retrospective case series. Median patients’ age was 68.7 years, and there were three male and ten female patients. Their diagnoses were nonunion in six patients and acute fracture in seven. Medical records and radiographic images were reviewed. Results: Twelve of thirteen fractures were united both clinically and radiologically within a year after adjuvant TPTD. Union completed radiologically median 5.4 months and clinically 5.7 months after the medication, respectively. Callus appeared abundantly showing median 1.4 of fracture healing response postoperatively. There was no serious adverse reaction of medication other than itching, muscle cramp, or nausea. Conclusion: Even appropriate surgical treatment is a mainstay of treatment for AFF, PPFF, and FNU, the current report suggested that adjuvant TPTD combined with stable fixation results in satisfactory outcome for the challenging fractures of femur.

Graphene oxides coated by tannic acid (GOT) can be obtained easily by the self-polymerization of tannic acid in basic buffer solution on a graphene oxide surface. Polyamide reverse osmosis nanocomposite membranes containing GOT in the active layer were prepared by the interfacial polymerization using an organic solution containing trimesoyl chloride and an aqueous solution containing m -phenylene diamine and GOT. The polyamide membrane containing GOT (PA-GOT) showed significantly improved performances such as water flux, chlorine resistance, and antimicrobial properties, compared to the polyamide membrane without any additives and the polyamide membranes containing only tannic acid and/or graphene oxide. These high performances of PA-GOT membrane could be ascribed to a various of advantageous properties of GOT such as improved hydrophilicity, oxidative stress capability, barrier property, and compatibility with the polymer matrix.

The high failure rate of cemented femoral components in the 1970s facilitated the improvement of the cementing technique and surface finishes such as polymethylmethacrylate (PMMA)-precoated stems, reporting a survival rate of >95% at 10 years from some studies. However, controversy persists regarding whether precoated femoral stems are associated with a longer revision-free prosthesis survival. The purpose of this study was to evaluate the clinical and radiological outcomes of PMMA-precoated femoral stems, and analyze factors associated with implant survival. We retrospectively reviewed 73 primary hybrid total hip arthroplasties performed using PMMA-precoated femoral stems. The mean age of the patients was 61 years. During the mean follow-up period of 13 years, 18 hips (24.7%) underwent aseptic loosening, and all of the loosened stems were subjected to revision surgery 8.8 years (range 4.6-15.5 years) from the index surgery. Younger age and poor cementing were significantly associated with aseptic loosening (P = 0.013 and P

Total hip arthroplasty (THA) is a treatment option for patients with advanced degenerative joint disease. Despite advances in THA, revision surgeries are necessitated by the long-term failure of implants using the conventional bearing material and polyethylene wear debris-induced periprosthetic osteolysis is the main cause of implant failure.1) To overcome this problem, several alternative bearing surfaces, including metal-on-metal (MoM) and ceramic-on-ceramic (CoC), were recently adopted for primary THA in young, active patients and yielded favorable midterm results.2,3) Nevertheless, substantial shortcomings of these alternative bearings have been reported, including metal ion-related problems with MoM THA or ceramic failure with CoC THA.2,4) Reported rates of adverse soft tissue reactions to metal debris for MoM bearings range from 0% to 39%,5,6) and the United States Food and Drug Administration (FDA) released a safety announcement in February 2011 addressing these issues. Although the rate of complications associated with CoC bearings is low, unpredictable risks of audible squeaking emanating from the bearing as well as ceramic fractures can be indications for revision.7,8) These problematic complications have led to a decline in the use of hard-on-hard alternative bearing surfaces in Western countries.9,10) There are three epidemiological studies of bearing surface usage in primary THAs in the United States.9,10,11) To our knowledge, however, there are no published studies of the epidemiology of bearing surfaces in Asian countries, nor have there been any studies tracking nationwide longitudinal bearing surface utilization in the general population. The disease pattern and age distribution of patients that undergo THA in East Asia are different from those in Western countries.12,13,14) Therefore, we postulated that the trends for bearing surface usage might also differ among countries. Moreover, taking into consideration the disclosed problems of alternative bearing surfaces, these issues in patients undergoing THA may be predicted by analyzing current national trends of bearing surface usage in primary THAs. In this study, we analyzed the data for primary THAs in the Korean nationwide database to assess (1) the epidemiology and national trends of bearing surface usage in primary THA in Korea and (2) the prevalence of each type of bearing surface according to age, gender, hospital type, primary payer, and hospital procedure volume.

Backgroud Outcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH. Methods Eighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint. Results Preoperatively, the necrotic lesion extent was 63.0% (38.4%-96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2). Conclusions Our outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.

A well-defined water-soluble superamphiphilic block copolymer surfactant containing superhydrophilic zwitterionic and very hydrophobic long alkyl units (PSbPDz) was synthesized via reversible addition-fragmentation chain-transfer polymerization for the replacement of the conventional surfactant used to polyamide (PA) thin-film reverse osmosis (RO) membrane. PSbPDz was found to act as a surfactant successfully, and work as a filler at the same time even after interfacial polymerization (IP) due to its entanglement effect of the polymer chains with the PA matrix. As the surfactant, PSbPDz improves the water wettability on the top surface of the support layers decreasing the thickness of the PA selective layer at the thinnest region and expands the interface area between the aqueous and organic phase increasing the roughness of the PA selective layer. As the filler, PSbPDz introduced into the PA selective layer increases the water wettability of the RO membrane. Hence, the RO membrane fabricated with 0.015 wt% of PSbPDz in the aqueous solution through IP shows much larger water permeance value (1.69 L m−2 h−1 bar−1) than the neat RO membrane (0.68 L m−2 h−1 bar−1) maintaining the high salt rejection value.

BackgroundAcetabular labral tears cause of pain in patients with symptomatic hip dysplasia. To date, no structured grading system has been developed to evaluate labral tears in these patients. The present study describes a new system of grading labral tears in patients with acetabular dysplasia.MethodsThe data of 66 patients who underwent hip arthroscopy for symptomatic hip dysplasia from March 2014 to February 2018 were reviewed. Labral tears were classified into four groups, based on the occurrence of chondrolabral junction (CLJ) disruption, capsulolabral recess (CLR) disruption, and labral displacement. Labral tears without instability were classified as grade 1 or 2. Partial delamination or blistering of the labrum with minimal fraying at the CLJ was classified as grade 1, whereas labral tears with CLJ disruption were classified as grade 2. Unstable labral tears with CLR disruption followed by CLJ disruption, but without labral displacement, were classified as grade 3, whereas unstable labral tears with CLR and CLJ disruption, but with labral displacement, were classified as grade 4. The radiological and clinical characteristics of patients in each grade were determined including by simple radiographs and MRI/MR arthrography, as were concomitant findings, including rupture of the ligamentum teres, articular cartilage damage, and presence of a paralabral cyst. The surgical options selected for each grade and clinical outcomes, including modified Harris hip scores (mHHS) and Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) scores, were evaluated. Spearman's correlation analyses were performed to assess whether labral tear grade correlated with baseline characteristics, the incidence of concomitant injuries, and the severity of osteoarthritis (OA). The Wilcoxon test for paired data was performed to compare treatment results with pain scores.ResultsThe study cohort included six men and 53 women of mean ± SD age 39.9 ± 13.0 years (range, 15-66 years). Of the 66 hips, seven (10.6%), 10 (15.2%), 30 (45.5%), and 19 (28.8%) were classified as grades 1-4, respectively. Symptom duration (P = 0.017), preoperative Tönnis OA grade (P < 0.001), cartilage damage (P < 0.001), and the presence of a paralabral cyst (P = 0.001) correlated significantly with baseline tear grade. In all groups, mHHS and WOMAC scores improved after surgical treatment.ConclusionsArthroscopic findings of labral tears in patients with hip dysplasia differed from the conventional classification. The classification system proposed in this study will likely be useful for determining the degree of labral tear in patients with hip dysplasia and for predicting treatment outcomes.