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Cu2SnS3 (CSS) has gained great attraction due to its constitutive earth-abundant elements and intrinsic low lattice thermal conductivity, κl, potentially providing high quality factor, B, and high zT value. However, the lack of band convergence is the bottleneck to enhancing the thermoelectric performance of Cu2SnS3 when performing the band engineering. To study the doping effect on the band structure and the thermoelectric performance, the composite Cu2Sn0.7Co0.3S3-xCuCl (x = 0, 0.1, 0.2, 0.3) (CSCS-xCuCl) has been investigated for the first time. The samples showed excellent data repeatability at high temperatures of up to 700 K. It was found that CuCl could compensate the Cu loss, enhance the phonon scattering and minimize the adverse effect on the power factor, PF. The ultralow lattice thermal conductivity could reach 0.38 W m−1 K−1 for the nominal composition of CSCS-0.3CuCl at 700 K. A peak zT of 0.56 (evaluated with no cold finger effect) was realized at 700 K when x = 0.3, which is almost double the performance of pristine samples.

With the development of high-temperature thermoelectric materials, especially the superionic copper selenide (Cu2−xSe), thermal stability and cycling thermoelectric performance have become a great concern recently. Here we demonstrate that the excellent repeatability of the thermal cycling data of a simple Cu–Se binary system can be obtained. The thermal stability was systematically studied via measuring the thermal-cycling thermoelectric performances of Cu1.97Se samples with different rates of Se evaporation by adopting a simple and controllable method, i.e., the conventional solid-state sintering method. The samples fabricated using the conventional sintering method exhibited an optimized figure of merit of 0.8 at 800 K with very good thermal repeatability and stability from 400 K to 800 K. The results indicated that the conventional sintering method can also be adopted to fabricate materials with satisfactory thermoelectric performance. It was found that the repeatability of thermal cycling data is directly related to the sintering temperature and indirectly associated with the evaporation of Se. The Cu1.97Se samples sintered at low temperatures experienced less evaporation of Se with good thermal repeatability, while they exhibited relatively low thermoelectric performance due to high carrier concentration. Although the samples sintered at high temperatures show a large variation in the thermal cycling performance, the repeatability could be improved by the further annealing process, which reveals that good thermal stability of thermoelectric materials can be obtained via post-treatment.

In this work, the crystal structure, thermal conductivity, as well as dielectric and electrical properties of poly(vinylidene fluoride-co-chlorotrifluoroethylene) [P(VDF-CTFE)] filled with two different carbon nanofillers including exfoliated graphite nanoplates (xGNPs) and multi-walled carbon nanotubes (MWCNTs) have been compared. The xGNPs and the MWCNTs were well dispersed in the P(VDF-CTFE) matrix using a simple solution-blending process. The xGNPs have the ability to induce the large amount of useful polar β and γ crystal phases for P(VDF-CTFE) via the relatively strong interfacial interaction between their functional groups and the dipoles of P(VDF-CTFE), while the MWCNTs only produce the relatively low amount of β crystal phases for P(VDF-CTFE) due to their weak π-dipole interactions with P(VDF-CTFE). It was found that both the electrical conductivity and dielectric properties of xGNPs/P(VDF-CTFE) composite were better than those of MWCNTs/P(VDF-CTFE) composite. The thermal conductivities of xGNPs/P(VDF-CTFE) composites were much higher when compared with those of MWCNTs/P(VDF-CTFE) composites at the same filler content, which is probably owing to the better compatibility between xGNPs and P(VDF-CTFE). For example, the thermal conductivities of xGNPs (5 wt%)/P(VDF-CTFE) composite and MWCNTs (5 wt%)/P(VDF-CTFE) composite were 0.83 W/mK and 0.43 W/mK, respectively.

Polystyrene-block-polybutadiene-block-polystyrene triblock copolymer (SBS) has the potential to be used as a dielectric elastomer for actuator, sensor, energy harvesting, and so on, but its low dielectric constant and thermal conductivity seriously limit this application. In this study, novel exfoliated graphite nanoplates (xGNPs)/SBS composites were prepared by a solution-blending method using N,N-dimethylformamide and tetrahydrofuran as co-solvents. Wide-angle X-ray diffraction measurement confirms that xGNPs have been incorporated into SBS. Furthermore, the result of scanning electron microscopy shows that xGNPs disperse well in the SBS matrix. The effects of xGNPs on the dielectric constant and thermal conductivity of the resultant xGNPs/SBS composites were investigated. The dielectric constant at 1,000 Hz significantly increased from 2.72 for pure SBS to 15.96 and 40.94 for xGNPs/SBS composite containing 1.19 and 1.27 vol.% of xGNPs, respectively. Moreover, the thermal conductivity of the xGNPs/SBS composite containing 1.27 vol.% of xGNPs has been improved from 0.18 to 0.41 W/m·K in comparison with that of pure SBS.

Organosilicate (OS)/poly(vinylidene fluoride) (PVDF) composites containing 2 and 4 wt% OS were prepared by the melt-blending method. It was confirmed by scanning electron microscopy that OS was homogeneously distributed in the PVDF matrix. The results of differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and wide angle X-ray diffraction indicated that the incorporation of OS along with stretching treatment could effectively transform PVDF crystallization from the stable α phase to the most useful electroactive β phase. The interfacial interaction between PVDF and OS was analyzed by X-ray photoelectron spectroscopy and zeta potential. The dielectric properties, AC conductivities, mechanical properties, Rockwell hardness, and thermal conductivity of resultant OS/PVDF composites have been measured. More importantly, the piezoelectric coefficient d 33 and pyroelectric coefficient p of stretched OS/PVDF composites were enhanced significantly in comparison with the pure PVDF, making them promising materials for self-powered electronic systems, thermal detectors, sensors, and actuators.

Phosphatidylethanolamine (PE)-binding protein 4 (PEBP4) is an antiapoptotic protein that is aberrantly expressed in various malignancies. We previously demonstrated that PEBP4 expression is dramatically induced in human gliomas and positively correlated with tumor grade and patient survival. However, the function of PEBP4 in human glioma development and underlying mechanisms remain largely unknown. By stable lentiviral vector-mediated silencing of PEBP4, we examined the effects of PEBP4 knockdown on the growth, apoptosis, and invasion of U251 and U373 human glioma cell lines using MTT, Transwell, colony formation, and flow cytometric assays. We examined the in vivo role of PEBP4 in tumor growth by inoculation of BALB/c nu/nu male mice with PEBP4-deficient U251 and U373 cells. The expression of cell cycle- and apoptosis-related proteins was analyzed by Western blotting and immunostaining. Knockdown of PEBP4 significantly reduced the proliferation and invasion of human glioma cells while inducing cell apoptosis by altering the expression of cell cycle- and apoptosis-related proteins. Mechanistically, PEBP4 knockdown led to activation of the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway, an effect that could be reversed by U0126, a selective inhibitor of MEK1/2 (upstream of ERK1/2), suggesting involvement of ERK1/2 signaling in the regulation of glioma development and progression by PEBP4. We identified PEBP4 as a novel regulator mediating human glioma cell proliferation, invasion, and apoptosis as well as tumor formation and growth. Therefore, PEBP4 may be a potential therapeutic target in human glioma treatment.

Using LiF and PbF 2 (mole ratio 1:1, LPF) as sintering additives, the x CoFe 2 O 4 /(1 − x ) Pb 0.9025 La 0.065 (Zr 0.58 Ti 0.42 ) 0.975 Nb 0.02 O 3 [ x = 0.1, 0.2, 0.3, and 0.4 in weight] (abbreviate as CFO/PLZT) 0–3 magnetoelectric (ME) composite ceramics were developed via a liquid phase sintering technique. A ZrO 2 layer was coated on the CFO particles via a sol–gel method in order to inhibit the diffusion of Fe 3+ and Co 2+ ions from the ferrite CFO phase to the ferroelectric PLZT phase. With using 6 wt% additives of LPF, dense composite ceramics can be obtained in a sintering temperature region of 1000–1150 °C for 30 min. Moreover, overall performance of the ceramics with relatively low CFO content ( x = 0.2) has been optimized. The effects of CFO content and sintering temperature on micromorphology, crystalline structure, piezoelectric, dielectric, and ME properties were investigated. It was found that the 0.2CFO/0.8PLZT composite ceramics exhibited a d 33 of 80 pC/N and a ME coefficient of 102 mV/Oe cm at 215 kHz.

We have developed a processing technique for producing cobalt ferrite (CFO)/lead lanthanum zirconate titanate (PLZT) 0-3 composites with enhanced piezoelectric, ferroelectric and magnetoelectrical (ME) coupling properties. It includes modifying the phase boundary with zirconia barrier layer and decreasing the sintering temperature with Li 2 O + 0.5Bi 2 O 3 additives. The CFO/PLZT 0-3 composites were successfully fabricated via conventional co-firing procedures. The obtained 0-3 composite ceramics can withstand a DC electric field of 6 kV mm −1 . The effects of CFO/PLZT ratio on the crystalline structure, piezoelectric, ferroelectric, dielectric and M–E properties were investigated. The M – E coefficients of the composites with CFO:PLZT volume ratio of 14.4:85.6, 27.4:72.6 and 39.3:60.7 were found to be 31, 52 and 143 mV (Oe cm) −1 at 100 kHz under a bias field of ∼1 kOe.

Fibroblast-like synoviocytes (FLS) with aberrant expression of microRNA (miRNA) are critical pathogenic regulators in rheumatoid arthritis (RA). Previous studies have found that overexpression or silencing of miRNA can contribute to the development of miRNA-based therapeutics in arthritis models. In this study, we explored the effects of miR-27a on cell migration and invasion in cultured FLS from RA patients. We found that miR-27a was markedly downregulated in the serum, synovial tissue, and FLS of RA patients. Meanwhile, the expression of follistatin-like protein 1 (FSTL1) was upregulated, which suggests that FSTL1 plays a key role in RA development. The results of a Transwell assay showed that miR-27a inhibited FLS migration and invasion. However, miR-27a inhibition promoted the migration and invasion of FLS. In addition, the down-regulated expression of matrix metalloproteinases (MMP2, MMP9, and MMP13) and Rho family proteins (Rac1, Cdc42, and RhoA) was detected after treatment with miR-27a in RA-FLS by quantitative reverse transcription-PCR and western blot analysis. Then, a luciferase reporter assay validated that miR-27a targeted the 3-untranslated region (3'-UTR) of FSTL1. Moreover, miR-27a caused a significant decrease of FSTL1. In addition, the expression of TLR4 and NFκB was inhibited by miR-27a but increased by FSTL1 overexpression. In conclusion, we found that miR-27a inhibited cell migration and invasion of RA-FLS by targeting FSTL1 and restraining the TLR4/NFκB pathway.

Abnormal expression of phosphatidylethanolamine-binding protein 4 (PEBP4) has been found in various types of malignancies. However, the PEBP4 expression in human gliomas is still unclear. In this study, we aim to compare the expression of PEBP4 in tumor samples derived from 58 patients with different grades of gliomas with that in 5 non-neoplastic brain samples and to investigate the clinical significance of PEBP4 expression in gliomas. The mRNA and protein expressions of PEBP4 were measured by real-time quantitative polymerase chain reaction and western blot, respectively. The intracellular expressions of PEBP4 in samples were examined by immunohistochemistry. The association between PEBP4 expression and the clinicopathologic characteristics of gliomas patients were analyzed. Our results demonstrated that the mRNA and protein levels of PEBP4 were upregulated in gliomas tissues, especially in high-grade (World Health Organization Grades III and IV) gliomas, when compared to normal control (p

Objective:The aim of this study was to investigate the arthroscopic characteristics of meniscal injuries in osteoarthritic knees and explore their significance in the selection of surgical approach.Methods: Four original types of meniscal injuries were defined. The study included 87 cases; 12 Type 1, 26 Type 2, 35 Type 3 and 14 in Type 4 meniscal injuries. For Type 1 injuries, 5 cases underwent meniscal suture repair and 7 cases partial meniscal resection. Partial meniscal resection was performed in 22 cases and subtotal resection in 4 cases of Type 2 injury. For Type 3 injury, meniscal debridement was performed in 2, partial resection in 8, subtotal resection in 19 and total resection in 6 cases. For Type 4 injury, 3 cases underwent subtotal resection and 11 underwent total resection. Patients were evaluated with the Lysholm, visual analog scale, and Kellgren-Lawrence scale scores and cartilage lesions stages.Results: Mean follow-up period was 26 (range: 8 to 51) months. Joint swelling or pain was present in 13 cases after fatigue. Twist lock symptom was observed in one Type 3 injury and one Type 4 injury. Joint flexion was limited to 20° in one Type 3 injury and two Type 4 injuries. Total knee joint replacement was performed in two Type 2 and two Type 4 injuries 2 to 3 years and 2 months after surgery.Conclusion: The classification of meniscal injuries in osteoarthritic knees was designed to guide arthroscopic surgery and improve the therapeutic efficacy of minimally invasive surgery for knee osteoarthritis., Amaç:Bu çalışmanın amacı osteoartritli dizlerde menisküs yaralanmalarının artroskopik karakteristiklerini incelemek ve uygulanacak cerrahi yaklaşımdaki önemini saptamaktı.Çalışma planı: Dört orijinal tipteki menisküs yaralanmaları tanımlandı. Çalışmaya katılan 87 olgunun 12’si Tip 1, 26’sı Tip 2, 35’i Tip 3 ve 14’ü Tip 4 menisküs yaralanmalarıydı. Tip 1 olguların 5’inin menisküsü sütür ile onarılırken, 7 olguda kısmi rezeksiyon; Tip 2 olguların 22’sinde kısmi rezeksiyon, 4’ünde subtotal rezeksiyon; Tip 3 olguların 2’sinde debridman, 8’inde kısmi rezeksiyon, 19’unda subtotal rezeksiyon, 6’sında total rezeksiyon; ve Tip 4 olguların 3’ünde subtotal rezeksiyon, 11’inde ise total rezeksiyon yapıldı. Hastalar Lysholm, görsel analog skala ve Kellgren-Lawrence skorları ve kıkırdak lezyonlarının evrelerine göre değerlendirildiler.Bulgular: Takip süresinin ortalama 26 (dağılım: 8-51) ay olduğu kaydedildi. On üç olguda yorgunluk sonrası eklemde şişlik ve ağrı gözlendi. Bir Tip 3 ve bir Tip 4 olguda kilitlenme semptomu mevcuttu. Tip 3 olguların birinde ve Tip 4 olguların ikisinde eklem fleksiyonu 20° ile kısıtlıydı. İki Tip 2 ve iki Tip 4 olguya cerrahi sonrası 2 yıl ila 3 yıl 2 ay sonrası dönemde total diz artroplastisi yapıldı.Çıkarımlar: Osteoartritli dizlerde menisküs yaralanmalarının sınıflandırması, artroskopi cerrahisine rehberlik etmesi amacıyla ve diz osteoartritinde minimal invaziv cerrahinin tedavi edici etkisini geliştirmek üzere tasarlanmıştır.

There is currently no consensus regarding the best graft type for anterior cruciate ligament reconstruction. Therefore, the aim of this study was to investigate the effects of patellar and hamstring tendon grafts on long-term knee function after anterior cruciate ligament reconstruction.This meta-analysis was conducted according to the methodological guidelines outlined by the Cochrane Collaboration. An electronic search of the literature was performed and all trials published between January 1966 and August 2011 comparing knee function after anterior cruciate ligament reconstruction using patellar tendon grafts with knee function after reconstruction with hamstring tendon grafts were pooled. Six studies were included in the final meta-analysis.Anterior cruciate ligament reconstruction using hamstring tendon grafts resulted in greater pain upon kneeling than reconstruction using patellar tendon grafts (P = 0.001). However, both grafts resulted in similar levels of anterior tibial translation, and similar results regarding isokinetic extension/flexion tests, Lysholm scores, and the stair-hop test (P0.05).Anterior cruciate ligament reconstruction using patellar or hamstring tendon grafts results in similar long-term knee function.

The anterior cruciate ligament (ACL) is one of the most commonly injured knee ligaments. Even following ACL reconstruction, significant articular cartilage degeneration can be observed and most patients suffer from premature osteoarthritis. Articular cartilage degeneration and osteoarthritis development after ACL injury are regarded as progressive process that are affected by cyclic loading during frequently performed low-intensity daily activities. The purpose of this study was to perform a meta analysis on studies assessing the effects of ACL reconstruction on kinematics, kinetics and proprioception of knee during level walking.This meta analysis was conducted according to the methodological guidelines outlined by the Cochrane Collaboration. An electronic search of the literature was performed and all trials published between January 1966 and July 2010 comparing gait and proprioception of a reconstructed-ACL group with an intact-ACL group were pooled for this review. Thirteen studies were included in the final meta analysis.There was no significant difference in step length, walking speed, maximum knee flexion angle during loading response, joint position sense and threshold to detect passive motion between the reconstructed-ACL group and the intact-ACL group (P0.05). However, there was a significant difference in peak knee flexion angle, maximum angular knee flexion excursion during stance, peak knee flexion moment during walking and maximum external tibial rotation angle throughout the gait cycle between the reconstructed-ACL group and the intact-ACL group (P0.05).Step length, walking speed, maximum knee flexion angle during loading response, joint position sense and threshold to detect passive motion usually observed with ACL deficiency were restored after the ACL reconstruction and rehabilitation, but no significant improvements were observed for peak knee flexion angle, maximum angular knee flexion excursion during stance, peak knee flexion moment during walking and maximum external tibial rotation angle throughout the gait cycle.

Upconversion transparent ceramics K0.5(1-y)Na0.5(1-y)LiyNb1-yBiyO3-Er0.005Yb0.005x(Er/Yb:KNNLB, x=0-3, y=0-0.09) were fabricated by hot-press sintering process using LiBiO3 as additives. The microstructure, optical transparency and upconversion fluorescence were investigated.The results show that the crystalline phase of the ceramics is orthorhombic-perovskite structure.The ceramics are well densified, and the grain size of the ceramics is about 0.5 μm.These ceramics present good transparency in the infrared and the long-wavelength visible regions, but the optical transparency declines rapidly in the visible region as the amount of Yb and Er ions increases.The transparency of the ceramics with y = 0.06 and x = 0 reaches 45% in the visible region and over 95% in the infrared region(the thickness of the sample is 0.5 mm).The strong upconversion fluorescence is observed when the ceramics are excited by the 900 nm-wavelength light of an xenon lamp.