[Protective effects of total saponins from Panax japonicus against high-fat diet-induced testicular Sertoli cell junction damage in mice]

OBJECTIVE

To investigate the protective effects of total saponins from Panax japonicus (TSPJ) against high-fat dietinduced testicular Sertoli cell junction damage in mice.

METHODS

Forty male C57BL/6J mice were randomized into normal diet group, high-fat diet group, and low-dose (25 mg/kg) and high-dose (75 mg/kg) TSPJ treatment groups (n=10). The mice in the normal diet group were fed a normal diet, while the mice in the other groups were fed a high-fat diet. After TSPJ treatment via intragastric administration for 5 months, the testes and epididymis of the mice were collected for measurement of weight, testicular and epididymal indices and sperm parameters. HE staining was used for histological evaluation of the testicular tissues and measurement of seminiferous tubule diameter and seminiferous epithelium height. The expression levels of ZO-1, occludin, claudin11, N-cadherin, E-cadherin and β-catenin in Sertoli cells were detected with Western blot, and the localization and expression levels of ZO-1 and β-catenin in the testicular tissues were detected with immunofluorescence assay. The protein expressions of LC3B, p-AKT and p-mTOR in testicular Sertoli cells were detected using double immunofluorescence assay.

RESULTS

Treatment with TSPJ significantly improved high-fat diet-induced testicular dysfunction by reducing body weight (P < 0.001), increasing testicular and epididymal indices (P < 0.05), and improving sperm concentration and sperm viability (P < 0.05). TSPJ ameliorated testicular pathologies and increased seminiferous epithelium height of the mice with high-fat diet feeding (P < 0.05) without affecting the seminiferous tubule diameter. TSPJ significantly increased the expression levels of ZO-1, occludin, N-cadherin, E-cadherin and β-catenin (P < 0.05) but did not affect claudin11 expression in the testicular tissues. Immunofluorescence assay showed that TSPJ significantly increased ZO-1 and β-catenin expression in the testicular tissues (P < 0.001), downregulated LC3B expression and upregulated p-AKT and p-mTOR expressions in testicular Sertoli cells.

CONCLUSION

TSPJ alleviates high-fat diet-induced damages of testicular Sertoli cell junctions and spermatogenesis possibly by activating the AKT/mTOR signaling pathway and inhibiting autophagy of testicular Sertoli cells.

[Pediatric myofibroma/myofibromatosis of the soft tissue and bone: a clinicopathological analysis of 28 cases]

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of pediatric myofibroma/myofibromatosis of the soft tissue and bone. Methods: All cases of pediatric myofibroma/myofibromatosis of the soft tissue and bone diagnosed between January 2011 and December 2018 were retrieved from the surgical pathology records in the Department of Pathology, Beijing Jishuitan Hospital, Beijing, China. Clinical and radiological data were collected. H&E and immunohistochemistry were used to examine histological and immunophenotypic features and to make the diagnosis and differential diagnosis. The relevant literature was also reviewed. Results: Twenty-eight cases of pediatric myofibroma/myofibromatosis of the soft tissue and bone were respectively collected. The patients' ages ranged from 2 months to 14 years, with a mean age of 7 years. There were 7 females and 21 males. There were 12 cases located in soft tissue, including the finger (n=9), upper arm (n=1) and foot (n=2). There were 14 cases located in the bone of limb, including the femur (n=8), tibia (n=4), clavicle (n=2), fibula (n=2) and radius (n=1). There were 2 cases of myofibromatosis involving multiple bones. Radiology showed lytic lesions in the bone. The proliferation of spindle-shaped myofibroblasts arranged in fascicles with indistinct eosinophilic cytoplasm and bland nuclei, with no pleomorphism and cytological atypia. The characteristic histologic structure was the biphasic nodular growth pattern with cellular and paucicellular regions. The tumors might arrange in a hemangiopericytoma-like pattern. The stroma varied between dense fibrosis and myxoid changes. The reactive new bone formation and inflammatory cell infiltration also existed. Immunohistochemical study showed that the SMA was positive. The surgical resections were performed. One of the patients had tumor recurrence as a result of 11-month follow-up. Conclusions: The pediatric myofibroma/myofibromatosis of the soft tissue and bone is a very rare benign tumor and has a good prognosis. It has a characteristic morphology and its differential diagnosis from other spindle cell tumors could be made with the immunohistochemical analysis.

Proteome Analysis of Temporomandibular Joint with Disc Displacement

Disc displacement without reduction is a common disorder of the temporomandibular joint, causing clinical symptoms and sometimes condylar degeneration. In some cases, bone regeneration is detected following disc-repositioning procedures. Until now, however, systems-wide knowledge of the protein levels for condylar outcome with disc position is still lacking. Here, we performed comprehensive expression profiling of synovial fluid from 109 patients with disc displacement without reduction using high-resolution data-independent acquisition mass spectrometry and characterized differences in 1,714 proteins. Based on magnetic resonance imaging, samples were divided into groups with versus without condylar absorption and subgroups with versus without new bone. For the proteomic analysis, 32 proteins in groups presented with statistical significance (>2-fold, P < 0.05). Pathways such as response to inorganic substances, blood coagulation, and estrogen signaling were significantly expressed in the group with bone absorption as compared with pathways such as regulation of body fluid levels, vesicle-mediated transport, and focal adhesion, which were enriched in the group without bone absorption. In subgroup analysis, 45 proteins of significant importance (>2-fold, P < 0.05) were associated with pathways including would healing, glycolysis and gluconeogenesis, and amino acid metabolism. Combined with clinical examination, molecules such as acetyl-CoA carboxylase beta (ACACB) and transforming growth factor beta 1 (TGFB1) were related to features such as visual analog scale and maximum interincisal opening (P < 0.05). In addition, 7 proteins were examined by Western blotting, including progesterone immunomodulatory binding factor 1 (PIBF1), histidine-rich glycoprotein (HRG), and protein kinase C and casein kinase substrate in neurons 2 (PACSIN2). In conclusion, this study provides the first proteome analysis of condylar absorption at disc displacement without reduction and postoperative new bone formation after disc reposition. Integrated with clinical data, this analysis provides an important insight into the proteomics of condylar modification at disc position.

Systolic blood pressure time in range and long-term clinical outcomes in patients with ischaemic cardiomyopathy

Background

The relationship between systolic blood pressure (SBP) control and long-term clinical outcomes in patients with ischaemic cardiomyopathy remains unclear. It has been previously reported that either too high or too low SBP may lead to a poorer prognosis. But current SBP control metrics may not take into account the possible effects of fluctuating SBP overtime on patients.

Purpose

This study aimed to estimate the association between time in range (TIR) of SBP and long-term clinical outcomes in patients with ischaemic cardiomyopathy.

Methods

This study was a post-hoc analysis of The Surgical Treatment of Ischaemic Heart Failure (STICH) trial, a randomized controlled trial with two hypotheses that enrolled participants with coronary artery disease and left ventricular ejection fraction ≤35%. The SBP target range of the TIR was defined as 110 to 130 mmHg and the SBP TIR was calculated by linear interpolation method. Patients were equally divided into four groups by quartiles of TIR. Multivariable-adjusted Cox proportional hazards regression models were constructed to compare the effects of different levels of TIR on a 10-year prognosis. The primary outcome was all-cause mortality. Subgroup analyses were performed according to whether patients were assigned to coronary artery bypass grafting (CABG) or medical therapy (MED), and in populations with different baseline SBP.

Results

A total of 1194 eligible patients were included according to the purpose of our study. Compared with patients in the quartile 4 group (TIR 77.87–100%), the fully adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of all-cause mortality were 1.32 (0.98–1.78) for quartile 3 group (TIR 54.81–77.63%), 1.40 (1.03–1.90) for quartile 2 group (TIR 32.59–54.67%), and 1.53 (1.14–2.04) for quartile 1 group (TIR 0–32.56%) (P for trend = 0.005). When evaluated TIR as a continuous variable, per 1-SD decrement (29.28%) in TIR significantly increased the incidence of all-cause mortality [1.15 (1.04–1.26)]. Similarly, the decrement in TIR significantly elevated the risk of cardiovascular (CV) mortality and the risk of all-cause mortality plus CV rehospitalization. Consistent results were also observed in subgroup analyses of either CABG or MED, or different baseline SBP, indicating the robustness of our findings.

Conclusions

This study suggested that in patients with ischaemic cardiomyopathy, a higher SBP TIR was significantly associated with a decreased risk of all-cause mortality, CV mortality and the composite of all-cause mortality plus CV rehospitalization, regardless of whether the patient received CABG or MED, and the level of baseline SBP. Our findings support that TIR might be a substitutable metric of SBP control for long-term clinical outcomes in patients with ischaemic cardiomyopathy.

Funding Acknowledgement

Type of funding sources: None.

Evolution and clinical implications of right ventricular dysfunction in ischemic cardiomyopathy with or without coronary artery bypass surgery

Background

The Surgical Treatment of Ischemic Heart Failure (STICH) trial demonstrated that coronary artery bypass grafting (CABG) provides additional survival benefits to patients with ischemic cardiomyopathy. However, it remains unclear whether this benefit is affected by preoperative right ventricular (RV) function and how post-therapeutic evolution of RV function influences long-term outcomes.

Purpose

We sought to investigate the implications of baseline RV function on therapeutic decision-making in patients with ischemic cardiomyopathy, and to evaluate the prognostic implications of post-therapeutic evolution of RV function.

Methods

Patients with available baseline echocardiographic RV function assessed by experienced Echocardiography Core Laboratory physicians were included from the hypothesis 1 of the STICH trial. The primary outcome was long-term all-cause mortality.

Results

A total of 1042 patients were included, among them 757 (72.7%) had normal RV function, 143 (13.7%) mild right ventricular dysfunction (RVD), and 142 (13.6%) moderate to severe RVD. After a median follow-up of 9.8 years, patients with RVD had a higher risk of all-cause mortality compared with patients with normal RV function [mild RVD: adjusted hazard ratio (aHR) 1.32; 95% confidence interval (CI) 1.06–1.64; moderate to severe RVD: aHR, 1.74; 95% CI 1.39–2.18]. Although no significant interaction was detected between RVD degree and treatment allocation (P for interaction = 0.399), a gradually decreasing survival benefit associated with CABG was observed among patients with normal RV function (aHR: 0.79; 95% CI: 0.65–0.96), mild RVD (aHR: 0.85; 95% CI: 0.56–1.29), and moderate to severe RVD (aHR: 0.97; 95% CI: 0.67–1.43). Among 746 patients with available RV function assessed at baseline and post-therapeutic 4-month follow-up, there was a gradient of increasing risk for all-cause mortality across patients with consistent normal RV function, recovery of RVD (aHR: 1.20; 95% CI: 0.88–1.64), newly developed RVD (aHR: 1.59; 95% CI: 1.18–2.14), and consistent RVD (aHR: 2.06; 95% CI: 1.60–2.67). Independent predictors of RVD recovery included baseline left ventricular ejection fraction (per 1-percent increment, adjusted odds ratio: 1.04; 95% CI: 1.00–1.09) and mitral regurgitation ≥ grade 2 (adjusted odds ratio: 0.42; 95% CI: 0.21–0.84).

Conclusions

Baseline RVD was associated with an increased risk of long-term mortality in patients with ischemic cardiomyopathy, and adding CABG to medical therapy might provide limited survival benefits in patients with moderate to severe RVD. A gradient of increasing risk for mortality was observed across different categories of RV function evolution, which emphasizes the necessity of pre- and post-therapeutic RV assessment for prognostic evaluation.

Funding Acknowledgement

Type of funding sources: None.

F-Type Pseudo-Halide Anions for High-Efficiency and Stable Wide-Band-Gap Inverted Perovskite Solar Cells with Fill Factor Exceeding 84

The quality of wide-band-gap (WBG) perovskite films plays an important role in tandem solar cells. Therefore, it is necessary to improve the performance of WBG perovskite films for the development of tandem solar cells. Here, we employ F-type pseudo-halogen additives (PF₆^- or BF₄^-) into perovskite precursors. The perovskite films with F-type pseudo-halogen additives have a larger grain size and higher crystal quality with lower defect density. At the same time, the perovskite lattice increases due to substitution of F-type pseudo-halogen anions for I^-/Br^-, and the stress distortion in the film is released, which effectively suppresses the recombination of carriers, reduces the charge transfer loss, and inhibits the phase separation. Finally, the power conversion efficiency (PCE) of the inverted 1.67 eV perovskite devices is significantly improved to over 20% with an impressive fill factor of 84.02% and excellent device stability. In addition, the PCE of the four-terminal (4T) perovskite/silicon tandem solar cells reached 27.35% (PF₆^-) and 27.11% (BF₄^-), respectively. This provides important guidance for further improving WBG perovskite solar cell performance.

Back-Contact Ionic Compound Engineering Boosting the Efficiency and Stability of Blade-Coated Perovskite Solar Cells

Surface defect passivation, which plays a vital role in achieving high-efficiency perovskite solar cells (PSCs) in a spin-coating process, is rarely compatible with a printing process. Currently, printing PSCs with high efficiency remains a challenge, as only a few laboratories realized an efficiency of over 20%. In this work, zwitterionic compounds 2-hydroxyethyl trimethyl ammonium chloride (HETACl) and butyltrimethylammonium chloride (BTACl) were introduced, both of which can spontaneously adsorb on the surface perovskite and form an ultrathin passivation layer by a dip coating method. The complex formed by the strong interaction of HETACl with MAI on the surface of the perovskite film leads to the formation of a rough perovskite surface, which affects the enhancement of device performance. BTACl with a chemically inert side chain induces a weak interaction with the perovskite. It is demonstrated that BTACl not only passivates surface defects of the perovskite but also heals the grain boundaries and results in more uniform crystallizations. Finally, PSCs upon BTACl treatment were blade-coated in an ambient environment with a relative humidity of <50%, which produced a champion efficiency of 20.5% with negligible hysteresis, and the active area of the cell device was 0.095 cm2. After being stored in air for 30 days, unencapsulated PSCs treated with BTACl retained 95% of their initial efficiency, which is far superior to that of the control and those treated with HETACl.

High-performance broadband position-sensitive detector based on lateral photovoltaic effect of PbSe heterostructure

PbSe has attracted considerable attention due to its promising applications in optoelectronics and energy harvesting. In this work, we explore the lateral photovoltaic effect (LPE) of PbSe films with a simple PbSe/Si heterostructure under nonuniform light illumination and zero-bias conditions. The LPE response is strongly dependent on the thickness of the PbSe film, but always shows a linear dependence on the laser spot position in an ultra-large working size of 5 mm and exhibits a wide photoresponse ranging from visible to near-infrared. The maximum position sensitivity can reach up to 190 mV/mm for the 15-nm-thick PbSe device at 1064 nm and nonlinearity is less than 4%, demonstrating its new potential application in novel position sensitive detectors (PSDs). Besides, the device also shows an ultrafast response speed, with the rise and fall time of ∼40 µs and ∼105 µs, respectively, and excellent reproducibility. These results bring great inspirations for developing high-performance broadband and self-powered PSDs based on the PbSe/Si heterostructure.

High precision machine learning-enabled ECG algorithm for predicting sites of idiopathic ventricular arrhythmia origin

Introduction

Radiofrequency catheter ablation (CA) is an efficient antiarrhythmic treatment with a class I indication for idiopathic ventricular arrhythmia (IVA). The accurate prediction of the origins of IVA can significantly increase the procedure success rate, reduce operation duration and decrease the risk of complications. The present work proposes an ECG analysis algorithm to estimate 21 possible origins of idiopathic ventricular arrhythmia at a clinical-grade level accuracy, which include left coronary cusp (LCC), right coronary cusp (RCC), aortomitral continuity (AMC), summit, LCC-RCC commissure, left His bundle, mitral valve (MV), left septal including left anterior fascicle (LAF), left posterior fascicle (LPF), left anterior papillary muscle (LAPM), left posterior papillary muscle (LPPM), anterior cusp (AC), left cusp (LC), right cusp (RC), RVOT septal, free wall, right His bundle, tricuspid valve (TV), and right anterior papillary muscle (RAPM).

Method

A total of 18,612 ECG recordings extracted from 545 patients who underwent successful CA to treat IVA were proportionally sampled into training, validation and testing cohorts. We designed four classification schemes responding to different hierarchical levels of the possible IVA origins. The first scheme will help the operators to figure out the origin from epicardium of left ventricular summit, right, and left ventricle. The second one can separate origins from left/right outflow tract and left/right non-out flow tract, respectively. The third one is able to predict 18 anatomical locations, and the fourth scheme can distinguish 21 possible sites. For every classification scheme, we compared 98 distinct machine learning models with optimized hyperparameter values obtained through extensive grid search and reported an optimal algorithm with the highest accuracy scores attained on the validation cohorts.

Results

In the first classification scheme used to predict right ventricular endocardium, left ventricular endocardium, and epicardium of left ventricular summit, the model achieved an accuracy of 99.79 (99.41–99.89) and a F1-score of 99.84 (99.6–99.96). For scheme 2, the proposed method reached an accuracy of 99.62 (99.09–99.78) and a F1-score of 99.42 (98.79–99.75). For scheme 3, the model achieved an accuracy of 97.78 (96.76–98.41), a F1-score of 97.74 (94.15–99.73), and an adjusted accuracy of 98.53 (98.33–99.15). For scheme 4 that can distinguish 21 origin sites, the proposed model attained an accuracy of 98.24 (97.36–98.71), a F1-score of 98.56 (97.88–99.12) and an adjusted accuracy of 98.75 (98.35–99.38).

Conclusion

The proposed machine learning model can be immediately and effortlessly deployed to electrophysiology labs allowing cardiologists to predict the exact origins of arrhythmia and provide an optimum treatment plan both before and during the CA procedure. This approach will significantly reduce the CA procedure duration and the risk of complications.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): 2020 Natural Science Foundation of Zhengjiang Province Confusion matrix for classification schemes

Comparison between a novel sirolimus-eluting bioresorbable scaffold with everolimus-eluting metallic stent in patients with coronary artery disease: three-year follow-up from the neovas rct study

Background

Previous trials and meta-analyses have demonstrated that risk of adverse clinical events, especially thrombosis and target vessel myocardial infarction is increasing between 1 and 3 years after Bioresorbable Scaffolds (BRS) implantation.

Purpose

We sought to evaluate the long-term clinical outcomes of a novel NeoVas BRS in comparison with cobalt chromium everolimus-eluting stent (EES) following implantation in patients with coronary artery disease by 3-year follow-up results from the NeoVas RCT.

Methods

Overall, 560 patients with a single de novo native coronary artery lesion with reference vessel diameter 2.5–3.75 mm and lesion length ≤20 mm were randomized 1:1 to NeoVas BRS vs. cobalt-chromium everolimus-eluting stents (CoCr-EES). Optical coherence tomography (OCT) and fractional flow reserve (FFR) were both performed in a pre-specified subgroup at 3-year follow-up. Clinical outcomes from NeoVas RCT were analyzed by randomized device (intention to treat) cumulative to 3 years.

Results

Over 3 years, the overall target lesion failure (TLF) rate was 6.9% in the NeoVas group and 6.1% in the CoCr-EES group (HR 1.13, 95% CI 0.59 to 2.18; p=0.71). There was no statistically significant difference of the definite or probable stent thrombosis between the NeoVas group and the CoCr-EES group (1.1% vs. 0.7%, HR 1.51, 95% CI 0.26 to 8.73, p=0.64). In a landmark analysis of TLF, we found no difference in rate of late events from 2 to 3 years between two groups. FFR was not significantly different between the two group at 3 years (NeoVas vs. CoCr-EES, 0.89±0.07 vs. 0.90±0.05). NeoVas was largely absorbed (72.26% ± 13.21%) examined by OCT follow-up. Of 55 patients who finished 3-year absorption analysis, NeoVas was totally absorbed in 4 patients.

Conclusions

At the 3-year follow-up in the Neovas RCT trial, overall TLF rates were comparable between Neovas BRS and CoCr-EES, and adverse event rates relating to device safety were not increased with Neovas BRS compared with CoCr-EES up to 3 years after implantation.

Funding Acknowledgement

Type of funding sources: None.

Additive Engineering for Efficient and Stable MAPbI3-Perovskite Solar Cells with an Efficiency of over 21

The high density of defects in MAPbI₃ perovskite films brings about severe carrier nonradiative recombination loss, which lowers the performance of MAPbI₃-based perovskite solar cells (PSCs). Here, methylamine cyanate (MAOCN) molecules were introduced into MAPbI₃ solutions to manipulate the crystallizatsion of the MAPbI₃ films. MAOCN molecules can slow down the volatilization rate of the solvent and delay the crystallization process of the MAPbI₃ film. The crystal quality of the MAPbI₃ films is effectively optimized without an additive residue. Perovskite films treated by MAOCN have lower defect density and longer carrier lifetime, which lowers the carrier recombination loss. Meanwhile, the MAPbI₃ film based on MAOCN has a more hydrophobic surface. The final MAPbI₃-based device efficiency reached 21.28% (V_OC = 1.126 V, J_SC = 23.29 mA/cm², and FF = 81.13). After 30 days of storage under atmospheric conditions, the efficiency of unencapsulated MAOCN-based PSCs only dropped by about 5%.

[Preliminary results of surgical treatment of fibrous dysplasia of proximal femur in children]

Objective: To investigate the surgical treatment, clinical effect and revision reasons of children with proximal femoral fibrous dysplasia(FD). Methods: The clinical data of 26 children with polyostotic FD of proximal femur who underwent surgery at Department of Pediatric Orthopaedics, Beijing Jishuitan Hospital from June 2016 to June 2018 were retrospectively analyzed. There were 18 males and 8 females with a mean age of 9.2 years (range:5 to 16 years).One of them was McCune Albright syndrome. Fifteen cases were in first operation and 11 cases were in revision operation. The operation methods and results were reviewed,and the causes of revision were analyzed. Results: Among the 15 children who underwent the first operation,13 cases underwent osteotomy or fracture reduction and interlocking intramedullary nail(IMN) fixation;One case underwent valgus osteotomy and pediatric hip plate(PHP)internal fixation;One case underwent valgus osteotomy+lesion curettage+allogeneic bone graft+PHP fixation. Among the 11 children who underwent revision surgery,9 cases were treated with IMN fixation,1 case with PHP fixation,and 1 case with PHP fixation+allogeneic bone graft. The causes of revision included distal fixation failed in 6 cases,proximal fixation failed in 3 cases,plate fixation failed in 5 cases,and recurrence occurred after curettage and artificial bone graft in 2 cases. Patients were followed up for 1.4 years(range:1.0 to 3.5 years) after recent operation. The osteotomy or fracture healed well with good deformity correction. Postoperative complications included infection in 1 case and local bone partial resorption in 1 case. Conclusions: Osteotomy combined with rigid internal fixation is an effective surgical treatment for fibrous dysplasia of proximal femur in children. Internal fixation should cover the whole length of lesion. Intramedullary nail is the most common choice. Because the growth of height and the progress of the disease itself,this deformity is prone to recur in children,needing closely follow-up after operation.

High-Responsivity, Fast, and Self-Powered Narrowband Perovskite Heterojunction Photodetectors with a Tunable Response Range in the Visible and Near-Infrared Region

In recent years, narrowband photodetectors (PDs) have been widely used in color imaging, spectral detection or discrimination, defense, and scientific research due to their special spectral selective responses. In this work, by combining organic-inorganic hybrid perovskite layers of different band gaps and thicknesses, a series of narrowband perovskite heterojunction PDs with a continuously adjustable spectral range in the visible and near-infrared range are designed and prepared. The PDs can achieve a narrowband photoresponse with a full width at half-maximum (FWHM) of less than 50 nm and a light rejection ratio (between 780 and 532 nm) of over 1100 and exhibit excellent photoresponse performances with an external quantum efficiency (EQE), responsivity (R), and detectivity (D*) as high as 50.3%, 0.331 A/W, and 4.27 × 10¹⁰ Jones, respectively. More importantly, the photoresponses of the PDs at zero bias are as good as those at the reverse bias voltages, indicating the outstanding self-powered property. In addition, a fast response time of ∼180/∼200 μs is obtained in the narrowband perovskite heterojunction, and the response speed nearly remains constant for different PDs in the whole tunable wavelength range, demonstrating the suitable and stable structure of the heterojunction, as well as the high crystalline quality of the perovskite layers. This work definitely provides a simple strategy for designing low-cost, high-photoresponsivity, fast speed, and self-powered narrowband PDs with a tunable spectral range.

Ambient sunlight-driven photothermal methanol dehydrogenation for syngas production with 32.9 % solar-to-hydrogen conversion efficiency

Methanol dehydrogenation is an efficient way to produce syngas with high quality. The current efficiency of sunlight-driven methanol dehydrogenation is poor, which is limited by the lack of excellent catalysts and effective methods to convert sunlight into chemicals. Here, we show that atomically substitutional Pt-doped in CeO₂ nanosheets (Pt_s-CeO₂) exhibit excellent methanol dehydrogenation activity with 500-hr level catalytic stability, 11 times higher than that of Pt nanoparticles/CeO₂. Further, we introduce a photothermal conversion device to heat Pt_s-CeO₂ up to 299°C under 1 sun irradiation owning to efficient full sunlight absorption and low heat dissipation, thus achieving an extraordinarily high methanol dehydrogenation performance with a 481.1 mmol g⁻¹ h⁻¹ of H₂ production rate and a high solar-to-hydrogen (STH) efficiency of 32.9%. Our method represents another progress for ambient sunlight-driven stable and active methanol dehydrogenation technology.

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Atomically substitutional Pt-doped CeO₂ is active and robust for CH₃OH dehydrogenation

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The photothermal conversion device can heat Pt_s-CeO₂ to 299°C under 1 sun irradiation

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The joint system achieves a one sun irradiated H₂ production rate of 481.1 mmol g⁻¹ h⁻¹

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This system delivers a high solar-to-H₂ efficiency of 32.9% under one sun irradiation

Type-II GaSb quantum dots grown on InAlAs/InP (001) by droplet epitaxy

GaSb quantum dots (QDs) have been grown by droplet epitaxy within InAlAs barrier layers on an InP (001) substrate. The droplet growth mode facilitates a larger size (average height ∼4.5 nm) and a lower density (∼6.3 × 10⁹ cm^-2) for the QDs than would be expected for the 4% lattice mismatch between GaSb and InAlAs. A type-II band alignment between the GaSb QDs and the InAlAs barriers is revealed by photoluminescence (PL) through a prominent blue-shift of ∼0.11 eV resulting from a six orders of magnitude increase in excitation power. Further confirmation of the type-II nature of these QDs is found through time-resolved PL studies showing a biexponential decay with a long carrier lifetime of ∼10.9 ns. These observations reveal new information for understanding the formation and properties of GaSb/InAlAs/InP QDs, which may be an optimum system for the development of both efficient memory cells and photovoltaic devices.

Photoluminescence characterization of wetting layer and carrier dynamics for coupled InGaAs/GaAs surface quantum dot pair structures

The optical properties are investigated by spectroscopic characterizations for bilayer InGaAs/GaAs quantum dot (QD) structures consisting of a layer of surface quantum dots (SQDs) separated from a layer of buried quantum dots (BQDs) by different GaAs spacers with thicknesses of 7 nm, 10.5 nm and 70 nm. The coupling from the BQDs to SQDs leads to carrier transfer for the two samples with thin spacers, 7 nm and 10.5 nm, in which QD pairs are obtained while not for the 70 nm spacer sample. The carrier tunneling time is measured to be 0.145 ns and 0.275 ns from BQDs to SQD through the 7 nm and 10.5 nm spacers, respectively. A weak emission band can be observed at the wavelength of ∼ 960 nm, while the excitation intensity dependent PL and PLE spectra show that this is from the wetting layer (WL) of the SQDs. This WL is very important for carrier dynamics in bilayer structures of BQDs and SQDs, including for carrier generation, capture, relaxation, tunneling, and recombination. These results provide useful information for understanding the optical properties of InGaAs SQDs and for using such hybrid structures as building blocks for surface sensing devices.

Lateral bipolar photoresistance effect in the CIGS heterojunction and its application in position sensitive detector and memory device

Cu(In,Ga)Se₂ (CIGS) based multilayer heterojunction, as one of the best high efficiency thin film solar cells, has attracted great interest due to its outstanding features. However, the present studies are primarily focused on the structure optimization and modulation in order to enhance the photoelectric conversion efficiency. Here, we exploit another application of this multilayer heterostructure in photoresistance-modulated position sensitive detector by introducing lateral photoresistance effect. The lateral photoresistance measurements show that this multilayer heterojunction exhibits a wide spectral response (~330 to ~1150 nm) and excellent bipolar photoresistance performances (position sensitivity of ~63.26 Ω/mm and nonlinearity <4.5%), and a fast response speed (rise and fall time of ~14.46 and ~14.42 ms, respectively). More importantly, based on the lateral photoresistance effect, the CIGS heterostructure may also be developed as a position-dependent resistance memory device, which can be modulated by changing laser intensity, wavelength, and bias voltage with excellent stability and repeatability, and the position resolution reaches up to 1 μm. These results can be well explained by considering the diffusion and the drift model of carriers in the CIGS multilayer heterojunction. This work provides a new approach of achieving novel photoelectric sensors and memory devices based on the traditional photovoltaic heterostructures.

Dual roles of misshapen/NIK-related kinase (MINK1) in osteoarthritis subtypes through the activation of TGFβ signaling

OBJECTIVE

To identify the role of misshapen/NIK-related kinase (MINK1) in age-related Osteoarthritis (OA) and injury-induced OA, and the effects of enhanced TGFβ signaling in these progresses.

DESIGN

The effect of MINK1 was analyzed with MINK1 knock out (Mink1-/-) mice and C57BL/6J mice. OA progress was studied in age-related OA and instability-associated OA (destabilization of the medial meniscus, DMM) models. The murine knee joint was evaluated through histological staining, Osteoarthritis Research Society International (OARSI) scores, immunohistochemistry, and μCT analysis. Primary chondrocytes were isolated from wild type and Mink1-/- mice and subjected to osteogenic induction and Western blot analysis.

RESULTS

MINK1 is highly expressed during cartilage development and in normal cartilage. Mink1-/- mice displayed markedly lower OARSI scores, aggrecan degradation neoepitope positive cells and increased Safranin O and pSMAD2 staining in aging-related OA model. However, in injury-induced OA, loss of MINK1 accelerates extracellular matrix (ECM) destruction, osteophyte formation, and subchondral bone sclerosis. Accelerated subchondral bone remodeling in Mink1-/- mice was accompanied with increased numbers of nestin-positive mesenchymal stem cells (MSCs) and osterix-positive osteoprogenitors. pSMAD2 staining was increased in the subchondral bone marrow of Mink1-/- mice and overexpression of MINK1 inhibited SMAD2 phosphorylation in vitro.

CONCLUSIONS

This study shows for the first time that activation of TGFβ/SMAD2 by MINK1 deficiency plays opposite roles in aging-related and injury-induced OA. MINK1 deficiency protects cartilage from degeneration in aging joints through increased SMAD2 activation in chondrocytes, while accelerating OA progress in injury-induced model through enhanced osteogenesis of MSCs in the subchondral bone. These findings provide insights for developing precision OA therapeutics targeting TGFβ/SMAD2 signaling.

Enhanced Light-Induced Transverse Thermoelectric Effect in Tilted BiCuSeO Film via the Ultra-thin AuNPs Layer

Significant enhancement of light-induced transverse thermoelectric (LITT) effect in tilted BiCuSeO film has been achieved via introduction of an ultra-thin layer of gold nanoparticles (AuNPs) with the thickness of a few nanometers. In both cases of pulsed and continuous light irradiation, about two times increment in the LITT voltage sensitivity is observed for the BiCuSeO film coated with 4-nm-thick AuNPs layer. This can be ascribed to the increased photo-thermal conversion efficiency in the LITT effect owing to the efficient usage of the incident light of AuNPs layer. Thicker AuNPs layer will suppress the voltage sensitivity increment due to the electrical connectivity effect. This work provides an effective strategy for optimizing the performance of thermal-type optical detectors based on the LITT effect.

Analyzing risk factors for recurrence of developmental coxa vara after surgery

PURPOSE

To evaluate the risk factors for developmental coxa vara (DCV) recurrence following valgus osteotomy of the proximal femur.

METHODS

We retrospectively reviewed records of 32 DCV patients (46 hips) treated surgically (2005 to 2012). Recurrence-related factors, including age at initial surgery, side, sex, fixation methods, diagnosis of coxa vara, premature capital femoral physeal closure and postoperative Hilgenreiner epiphyseal (HE) angle, head-shaft (HS) angle, medial femoral offset and posterior slope angle (PSA) were analyzed.

RESULTS

At 4.7-year mean follow-up, 12 hip deformities recurred (26%). Postoperative HE angle > 41° and negative offset were statistically significant univariate and multivariate risk factors for the deformity recurrence. Increased PSA was common preoperatively, which accounted for 59% of hips. Postoperative PSA > 20° was associated with a high recurrence rate in the univariate analysis. Age was another univariate risk factor for the recurrence. Recurrence rate was 52% in the < 6.5-year age group versus 4% in the > 6.5-year age group. Other factors were not statistically significantly related to recurrence.

CONCLUSION

DCV is a 3D deformity. To prevent recurrence, HE angle should be restored to < 41° in the coronal plane. Sagittal malalignment (abnormal PSA) should be corrected concurrently, so that, the direction of surgical correction is along the true deformity plane. During valgus osteotomy, the distal fragment should be lateralized to maintain a normal mechanical axis.

LEVEL OF EVIDENCE

IV.

[Effects of physeal bar resection in treating post-traumatic distal radius partial physeal arrest]

Objective: To evaluate the effects of treatment of post-traumatic distal radius partial physeal arrest with physeal bar resection. Methods: From February 2007 to November 2017, 11 children with distal radius physeal arrest received physeal bar resection in the Department of Pediatric Orthopedics, Beijing Jishuitan Hospital. There were 2 females and 9 males. The average age of the patients was (10.1±1.8) years (range,7-13 years). All cases had previous history of distal radius trauma. The average duration from the previous fracture to the physeal bar resection operation was (22.8±3.2) months (range,22 to 41 months). Clinical and radiological evidence of distal radius physeal arrest were suggested in all patients. A CT or MRI scan was performed preoperatively to assess the size of the physeal bridge. Inclusion criteria were patients with a physeal bridge<30% of the physeal area,and with at least 2 years of growth remaining. The physeal bar resection operation was performed with the assistance of either fluoroscopy (5 cases) or intraoperative three dimensional navigation (6 cases). After resection, the void was then filled with bone wax in all cases and distal ulnar epiphysiodesis was conducted in 5 cases. The mean follow-up duration was (3.7±1.6) years (range,1-9 years). The clinical examination data and X ray were obtained during the follow up. Results: Four cases obtained fully recovery from the operation and the deformity got fully correction. The X ray showed no bone bridge recurred. The deformity did not aggravate in 1 case. The deformity aggravated and subsequent osteotomy was conducted in the left 6 cases. Three cases in the navigation group obtained fully recovery. One case in the fluoroscopy group obtained fully recovery. Conclusions: The intraoperative three dimensional navigation can precisely locate the bone bridge. The physeal bar resection is an effective technique in some post-traumatic distal radius partial physeal arrest.

Interplay Effect of Temperature and Excitation Intensity on the Photoluminescence Characteristics of InGaAs/GaAs Surface Quantum Dots

We investigate the optical properties of InGaAs surface quantum dots (SQDs) in a composite nanostructure with a layer of similarly grown buried quantum dots (BQDs) separated by a thick GaAs spacer, but with varied areal densities of SQDs controlled by using different growth temperatures. Such SQDs behave differently from the BQDs, depending on the surface morphology. Dedicated photoluminescence (PL) measurements for the SQDs grown at 505 °C reveal that the SQD emission follows different relaxation channels while exhibiting abnormal thermal quenching. The PL intensity ratio between the SQDs and BQDs demonstrates interplay between excitation intensity and temperature. These observations suggest a strong dependence on the surface for carrier dynamics of the SQDs, depending on the temperature and excitation intensity.

Correlation between photoluminescence and morphology for single layer self-assembled InGaAs/GaAs quantum dots

Single layer self-assembled InGaAs quantum dots (QDs) are manipulated by using different arsenic species on GaAs (100) surface. The As₄ molecules are experimentally observed to be more promising than As₂ to promote the formation of one-dimensionally-aligned QD-chain arrays. The lateral alignment of QDs and the corresponding formation of dot chains are explained by the anisotropic surface kinetics in combination with the different reactivities of the two molecules with bonding sites on the GaAs (100) surface. Photoluminescence (PL) measurements demonstrate that the spectra of the QD-chains broaden to higher energy and increases in intensity with increasing excitation laser power. The PL band of the QD-chains also exhibits a 9 meV reduction in linewidth as temperature increases starting from 8 K. These observations confirm an efficient lateral coupling between neighboring QDs and thereafter polarized QD emission, whereas the randomly distributed QDs grown with As₂ show no preferential polarization. Such QD-chains exhibiting anisotropic properties have the potential for nanophotonics applications like electro-optic modulators with very low drive voltage and ultra-wide bandwidth operation.

High-Efficiency and Stable Organic Solar Cells Enabled by Dual Cathode Buffer Layers

Various cathode interface materials have been used in organic solar cells (OSCs) to realize high performance. However, most cathode interface materials have their respective weaknesses in maximizing the efficiency or stability of OSCs. Herein, three kinds of alcohol-soluble cathode interfacial materials are combined with bathocuproine (BCP) to serve as multifunctional bilayer cathode buffers for the regular OSCs, and thus greatly enhanced power conversion efficiencies over 10.11% and significantly improved device stability have been achieved. By utilizing double interlayers, both light absorption and light distribution in active layer are improved. Furthermore, double interlayers offer favorable energy-level alignment, alcohol treatment, and duplicate protection of active layer, resulting in significantly reduced leakage current, suppressed recombination, and efficient charge collection. The improved device stability is related to the blocking effect of the complex formed between BCP and the metal electrode and the additional protection effect of the underlying alcohol-soluble materials. In view of the universal use of alcohol-soluble organic electrolyte as cathode buffer layers and by courtesy of the superiority of the double cathode layers relative to the monolayer controls, the double interlayer strategy demonstrated here opens a new way to fully exploiting the potential of OSCs and is believed to be extended to a wider application.

Ultrahigh, Ultrafast, and Self-Powered Visible-Near-Infrared Optical Position-Sensitive Detector Based on a CVD-Prepared Vertically Standing Few-Layer MoS2/Si Heterojunction

MoS2, as a typical transition metal dichalcogenide, has attracted great interest because of its distinctive electronic, optical, and catalytic properties. However, its advantages of strong light absorption and fast intralayer mobility cannot be well developed in the usual reported monolayer/few-layer structures, which make the performances of MoS2-based devices undesirable. Here, large-area, high-quality, and vertically oriented few-layer MoS2 (V-MoS2) nanosheets are prepared by chemical vapor deposition and successfully transferred onto an Si substrate to form the V-MoS2/Si heterojunction. Because of the strong light absorption and the fast carrier transport speed of the V-MoS2 nanosheets, as well as the strong built-in electric field at the interface of V-MoS2 and Si, lateral photovoltaic effect (LPE) measurements suggest that the V-MoS2/Si heterojunction is a self-powered, high-performance position sensitive detector (PSD). The PSD demonstrates ultrahigh position sensitivity over a wide spectrum, ranging from 350 to 1100 nm, with position sensitivity up to 401.1 mV mm-1, and shows an ultrafast response speed of 16 ns with excellent stability and reproducibility. Moreover, considering the special carrier transport process in LPE, for the first time, the intralayer and the interlayer transport times in V-MoS2 are obtained experimentally as 5 and 11 ns, respectively.

Synthesis of Na-doped ZnO hollow spheres with improved photocatalytic activity for hydrogen production

The fabrication of p-type doped ZnO nanostructures is key in opening up substantial opportunities for the application of ZnO nanostructures. Owing to their stable p-type property, Na ions are the best candidates for ZnO p-type doping. However, Na-doped ZnO nanostructures had never been prepared until now. For the first time, we successfully synthesized Na-doped ZnO ultrathin hollow spheres using an ion adsorption and templating method. The obtained hollow spheres have ultrathin shells, uniform Na elemental distribution and a controllable concentration of doped Na. The energy position of the Fermi level decreased with continuously increasing Na doping concentration, revealing the p-type conductivity of Na-doped ZnO. We demonstrate that the photocatalytic hydrogen generation efficiency (with methanol) using ZnO ultrathin hollow spheres can be enhanced by more than 50 times after Na-doping and that the quantum efficiency can be as high as 13.5%.

Enhanced thermoelectric performance of CdO : Ag nanocomposites

CdO : Ag nanocomposites with metallic Ag nanoparticles embedded in the polycrystalline CdO matrix were synthesized by the solid-state reaction method. The addition of Ag led to increased grain boundaries of CdO and created numerous CdO/Ag interfaces. By incorporating Ag into the CdO matrix, the power factor was increased which was probably due to the carrier energy filtering effect induced by the enhanced energy-dependent scattering of electrons. In addition, reduced thermal conductivity was also achieved by stronger phonon scattering from grain boundaries, CdO/Ag interfaces and Ag nanoparticles. These concomitant effects resulted in enhanced ZT values for all CdO : Ag nanocomposites, demonstrating that the strategy of introducing metallic Ag nanoparticles into the CdO host was very effective in optimizing the thermoelectric performance.

Photoluminescence Study of the Interface Fluctuation Effect for InGaAs/InAlAs/InP Single Quantum Well with Different Thickness

Photoluminescence (PL) is investigated as a function of the excitation intensity and temperature for lattice-matched InGaAs/InAlAs quantum well (QW) structures with well thicknesses of 7 and 15 nm, respectively. At low temperature, interface fluctuations result in the 7-nm QW PL exhibiting a blueshift of 15 meV, a narrowing of the linewidth (full width at half maximum, FWHM) from 20.3 to 10 meV, and a clear transition of the spectral profile with the laser excitation intensity increasing four orders in magnitude. The 7-nm QW PL also has a larger blueshift and FWHM variation than the 15-nm QW as the temperature increases from 10 to ~50 K. Finally, simulations of this system which correlate with the experimental observations indicate that a thin QW must be more affected by interface fluctuations and their resulting potential fluctuations than a thick QW. This work provides useful information on guiding the growth to achieve optimized InGaAs/InAlAs QWs for applications with different QW thicknesses.

Large Lateral Photovoltage Observed in MoS2 Thickness-Modulated ITO/MoS2/p-Si Heterojunctions

Molybdenum disulfide (MoS₂), as a typical two-dimensional (2D) material, has attracted extensive attention in recent years because of its fascinating optical and electric properties. However, the applications of MoS₂ have been mainly in photovoltaic devices, field-effect transistors, photodetectors, and gas sensors. Here, it is demonstrated that MoS₂ can be found another important application in position sensitive detector (PSD) based on lateral photovoltaic effect (LPE) in it. The ITO/MoS₂(3, 5, 7, 9, 10, 20, 50, 100 nm)/p-Si heterojunctions were successfully prepared with vertically standing nanosheet structure of MoS₂. Because of the special structure and the strong light absorption of the relatively thick MoS₂ film, the ITO/MoS₂/p-Si heterojunction exhibits an abnormal thickness-dependent LPE, which can be ascribed to the n- to p-type transformation of MoS₂. Moreover, the LPE of ITO/MoS₂/p-Si structure improves greatly because of forward enhanced built-in field by type transformation in a wide spectrum response ranging from visible to near-infrared, especially the noticeable improvement in infrared region, indicating its great potential application in infrared PSDs. This work not only suggest that the ITO/MoS₂/p-Si heterojunction shows great potential in LPE-based sensors, but also unveils the importance of type transformation of MoS₂ in MoS₂-based photoelectric devices besides strong light absorption and suitable bandgap.

Production and genetic analysis of resynthesized Brassica napus from a B. rapa landrace from the Qinghai-Tibet Plateau and B. alboglabra

This study aimed to reveal the genetic and epigenetic variations involved in a resynthesized Brassica napus (AACC) generated from a hybridization between a B. rapa (AA) landrace and B. alboglabra (CC). Amplified fragment length polymorphism (AFLP), methylation-sensitive amplified polymorphism, and the cDNA-AFLP technique were performed to detect changes between different generations at the genome, methylation, and transcription levels. We obtained 30 lines of resynthesized B. napus with a mean 1000-seed weight of over 7.50 g. All of the lines were self-compatible, probably because both parents were self-compatible. At the genome level, the S0 generation had the lowest frequency of variations (0.18%) and the S3 generation had the highest (6.07%). The main variation pattern was the elimination of amplified restriction fragments on the CC genome from the S0 to the S4 generations. At the methylation level, we found three loci that exhibited altered methylation patterns on the parental A genome; the variance rate was 1.35%. At the transcription level, we detected 43.77% reverse mutations and 37.56% deletion mutations that mainly occurred on the A and C genomes, respectively, in the S3 generation. Our results highlight the genetic variations that occur during the diploidization of resynthesized B. napus.

Enhanced thermoelectric performance in Mg and Ca substituted CdO ceramics

A high ZT of 0.5 at about 1000 K has been achieved in Cd_0.94Mg_0.03Ca_0.03O, which is the highest ZT ever reported among n-type oxides in this temperature range.

Electronic Coupling in Nanoscale InAs/GaAs Quantum Dot Pairs Separated by a Thin Ga(Al)As Spacer

The electronic coupling in vertically aligned InAs/GaAs quantum dot (QD) pairs is investigated by photoluminescence (PL) measurements. A thin Al0.5Ga0.5As barrier greatly changes the energy transfer process and the optical performance of the QD pairs. As a result, the QD PL intensity ratio shows different dependence on the intensity and wavelength of the excitation laser. Time-resolved PL measurements give a carrier tunneling time of 380 ps from the seed layer QDs to the top layer QDs while it elongates to 780 ps after inserting the thin Al0.5Ga0.5As barrier. These results provide useful information for fabrication and investigation of artificial QD molecules for implementing quantum computation applications.

Identification of candidate causal genes and their associated pathogenic mechanisms underlying teratozoospermia based on the spermatozoa transcript profiles

Teratozoospermia with unclear pathomechanism is one of the common causes for failed fertilisation. This study aimed to further explore the pathological mechanism for teratozoospermia. Spermatozoal transcript profiles generated from 13 normal fertile men and eight infertile males with a consistent severe heterogeneous teratozoospermia were used. These data were pre-processed, and differentially expressed genes were screened. Besides, gene ontology and pathway enrichment analysis were performed, and then, protein-protein interaction (PPI) network was constructed, and spermatogenesis-related genes in the PPI network were extracted. As a result, 366 up-regulated and 2158 down-regulated genes were identified. Multiple gene ontology terms and pathways including cell-cell signalling and reproduction enriched by differentially expressed genes were obtained. Moreover, four clusters including cluster 1 associated with RNA catabolic process were identified from the PPI network. In addition, genes including cyclin B1, proteasome (prosome, macropain) activator subunit 4, Rac GTPase-activating protein 1 and pituitary tumour-transforming 1 were received. In conclusion, abnormal expression of cyclin B1 and Rac GTPase-activating protein 1, still proteasome (prosome, macropain) activator subunit 4 and pituitary tumour-transforming 1 would impede cell cycle progression during sperm development and maturation, which may contribute to the occurrence and development of teratozoospermia.

Tigecycline exerts an antitumoral effect in oral squamous cell carcinoma

OBJECTIVE

To explore whether antibacterial drug tigecycline could exert an antitumoral effect in oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Two OSCC cell lines Tca8113 and KB were used in this study. To investigate the cytostatic effects of tigecycline in OSCC, cell growth was tested by trypan blue staining, MTT assay, and Brdu immunofluorescence staining. Then, the apoptosis proportion was measured by FITC Annexin-V and PI labeling, and cell cycle was determined by PI staining. The expression of caspase 3 (CASP3) and cell cycle regulatory protein was detected by Western blot assay. Finally, the clonogenesis and tumorigenesis capacity were analyzed by soft agar growth and xenograft model.

RESULTS

Here, we showed that tigecycline significantly inhibited cell growth and proliferation in OSCC cell lines Tca8113 and KB. It did not induce cell apoptosis but led to an increase of cells in G0/G1 phase with down-regulation of cyclin E2 (CCNE2) and cyclin-dependent kinase4 (CDK4) protein expression. We also showed that tigecycline inhibited colony formation in soft agar and reduced tumor growth in a xenograft model.

CONCLUSION

Our results suggested that tigecycline might be used as a novel candidate agent for the treatment of OSCC.