HGM-cNet: Integrating hippocampal gray matter probability map into a cascaded deep learning framework improves hippocampus segmentation.

A robust cascaded deep learning framework with integrated hippocampal gray matter (HGM) probability map was developed to improve the hippocampus segmentation (called HGM-cNet) due to its significance in various neuropsychiatric disorders such as Alzheimer's disease (AD). Particularly, the HGM-cNet cascaded two identical convolutional neural networks (CNN), where each CNN was devised by incorporating Attention Block, Residual Block, and DropBlock into the typical encoder-decoder architecture. The two CNNs were skip-connected between encoder components at each scale. The adoption of the cascaded deep learning framework was to conveniently incorporate the HGM probability map with the feature map generated by the first CNN. Experiments on 135T1-weighted MRI scans and manual hippocampal labels from publicly available ADNI-HarP dataset demonstrated that the proposed HGM-cNet outperformed seven multi-atlas-based hippocampus segmentation methods and six deep learning methods under comparison in most evaluation metrics. The Dice (average > 0.89 for both left and right hippocampus) was increased by around or more than 1% over other methods. The HGM-cNet also achieved a superior hippocampus segmentation performance in each group of cognitive normal, mild cognitive impairment, and AD. The stability, conveniences and generalizability of the cascaded deep learning framework with integrated HGM probability map in improving hippocampus segmentation was validated by replacing the proposed CNN with 3D-UNet, Atten-UNet, HippoDeep, QuickNet, DeepHarp, and TransBTS models. The integration of the HGM probability map in the cascaded deep learning framework was also demonstrated to facilitate capturing hippocampal atrophy more accurately than alternative methods in AD analysis. The codes are publicly available at https://github.com/Liu1436510768/HGM-cNet.git.

Lifetime over 10000 hours for organic solar cells with Ir/IrOx electron-transporting layer.

The stability of organic solar cells is a key issue to promote practical applications. Herein, we demonstrate that the device performance of organic solar cells is enhanced by an Ir/IrOx electron-transporting layer, benefiting from its suitable work function and heterogeneous distribution of surface energy in nanoscale. Notably, the champion Ir/IrOx-based devices exhibit superior stabilities under shelf storing (T80 = 56696 h), thermal aging (T70 = 13920 h), and maximum power point tracking (T80 = 1058 h), compared to the ZnO-based devices. It can be attributed to the stable morphology of photoactive layer resulting from the optimized molecular distribution of the donor and acceptor and the absence of photocatalysis in the Ir/IrOx-based devices, which helps to maintain the improved charge extraction and inhibited charge recombination in the aged devices. This work provides a reliable and efficient electron-transporting material toward stable organic solar cells.

Frequent EGFR exon 20 insertion in the so-called peripheral-type squamous cell neoplasm of uncertain malignant potential: a variant of bronchiolar adenoma or under-recognised entity?

INTRODUCTION: Herein we describe a series of rare peripheral pulmonary neoplasms temporarily termed "peripheral type squamous cell neoplasm of uncertain malignant potential (PSCN-UMP)" and investigate their relationship to bronchiolar adenoma (BA) and squamous cell carcinoma (SCC). MATERIALS AND METHODS: The histologic and immunohistochemical features of 10 PSCN-UMPs and six BAs were compared. Whole exome sequencing (WES) and bioinformatics analysis were performed to further compare the genetic features of PSCN-UMPs, BAs, and NSCLCs. RESULTS: All PSCN-UMPs were peripherally located and histologically characterised by the lepidic, nested, and papillary proliferation of relatively bland squamous cells, accompanied by entrapped hyperplastic reactive pneumocytes. The basal squamous cells coexpressed TTF1 and squamous markers. Both cellular components exhibited bland morphology and a low proliferative activity. The six BAs met the morphologic and immunophenotypic features of proximal-type BA. Genetically, driver mutations, including frequent EGFR exon 20 insertions, were found in PSCN-UMPs, while the KRAS mutation, BRAF mutation, and ERC1::RET fusion were detected in BAs. PSCN-UMPs also shared some alterations with BAs in mutational signatures, while copy number variants (CNV) were enriched in MET and NKX2-1 in PSCN-UMP and MCL1, MECOM, SGK1, and PRKAR1A in BA. CONCLUSION: PSCN-UMPs exhibited the proliferation of bland squamous cells accompanied by entrapped pneumocytes and frequent EGFR exon 20 insertions, which showed distinct features from BAs and SCCs. Recognition of this specific entity will help to expand the morphologic and molecular spectrum of peripheral lung squamous neoplasms.

"Extended Frontalis Muscle Advancement Technique for Severe Congenital Blepharoptosis".

BACKGROUND: The conventional frontalis muscle advancement technique still has some disadvantages, such as residual lagophthalmos, eyebrow ptosis, eyelid contour abnormality, and under-correction. This article describes the authors' extended frontalis muscle advancement technique that takes extensive subcutaneous separation through the eyelid crease incision for the treatment of severe congenital blepharoptosis. METHODS: A retrospective review was performed that included patients with severe congenital ptosis who underwent extended frontalis muscle advancement technique from April of 2019 to April of 2021. Preoperative evaluation included age, sex, and margin reflex distance 1 (MRD1), levator function, and lagophthalmos. Postoperative evaluation including correction result, closure function of eyelid, cosmetic result was performed at the last follow-up. RESULTS: From April of 2019 to April of 2021, a total of 102 patients (137 eyes) who underwent extended frontalis muscle advancement technique were included in the study. The mean postoperative MRD1 in unilateral and bilateral ptosis patients was 3.84 ± 0.60 mm and 3.86 ± 0.56, respectively, and 126 eyes (92.0 percent) showed successful correction. Postoperatively, the mean residual lagophthalmos was 0.88 ± 1.40 mm, and 127 eyes (92.7 percent) showed excellent or good eyelid closure function. The average score of cosmetic results was 8.29 ± 1.34, and 94 patients (92.2 percent) had an excellent or good cosmetic result. CONCLUSIONS: Extensive subcutaneous separation relieves the mutual restriction between the forehead skin and frontalis muscle. The extended frontalis muscle advancement technique is effective in correcting severe congenital ptosis, while minimizing under-correction, residual lagophthalmos, eyelid contour abnormality and eyebrow ptosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

A comprehensive characterization of hippocampal feature ensemble serves as individualized brain signature for Alzheimer's disease: deep learning analysis in 3238 participants worldwide.

OBJECTIVES: Hippocampal characterization is one of the most significant hallmarks of Alzheimer's disease (AD); rather, the single-level feature is insufficient. A comprehensive hippocampal characterization is pivotal for developing a well-performing biomarker for AD. To verify whether a comprehensive characterization of hippocampal features of gray matter volume, segmentation probability, and radiomics features could better distinguish AD from normal control (NC), and to investigate whether the classification decision score could serve as a robust and individualized brain signature. METHODS: A total of 3238 participants' structural MRI from four independent databases were employed to conduct a 3D residual attention network (3DRA-Net) to classify NC, mild cognitive impairment (MCI), and AD. The generalization was validated under inter-database cross-validation. The neurobiological basis of the classification decision score as a neuroimaging biomarker was systematically investigated by association with clinical profiles, as well as longitudinal trajectory analysis to reveal AD progression. All image analyses were performed only upon the single modality of T1-weighted MRI. RESULTS: Our study exhibited an outstanding performance (ACC = 91.6%, AUC = 0.95) of the comprehensive characterization of hippocampal features in distinguishing AD (n = 282) from NC (n = 603) in Alzheimer's Disease Neuroimaging Initiative cohort, and ACC = 89.2% and AUC = 0.93 under external validation. More importantly, the constructed score was significantly correlated with clinical profiles (p < 0.05), and dynamically altered over the AD longitudinal progression, provided compelling evidence of a solid neurobiological basis. CONCLUSIONS: This systemic study highlights the potential of the comprehensive characterization of hippocampal features to provide an individualized, generalizable, and biologically plausible neuroimaging biomarker for early detection of AD. KEY POINTS: • The comprehensive characterization of hippocampal features exhibited ACC = 91.6% (AUC = 0.95) in classifying AD from NC under intra-database cross-validation, and ACC = 89.2% (AUC = 0.93) in external validation. • The constructed classification score was significantly associated with clinical profiles, and dynamically altered over the AD longitudinal progression, which highlighted its potential of being an individualized, generalizable, and biologically plausible neuroimaging biomarker for early detection of AD.

Bi-Deficiency Leading to High-Performance in Mg3 (Sb,Bi)2 -Based Thermoelectric Materials.

Mg3 (Sb,Bi)2 is a potential nearly-room temperature thermoelectric compound composed of earth-abundant elements. However, complex defect tuning and exceptional microstructural control are required. Prior studies have confirmed the detrimental effect of Mg vacancies in Mg3 (Sb,Bi)2 . This study proposes an approach to mitigating the negative scattering effect of Mg vacancies (VMg ) by Bi deficiency, synergistically modulating the electrical and thermal transport properties to enhance the thermoelectric performance. Positron annihilation spectrometry and Cs -corrected scanning transmission electron microscopy analyses indicated that the VMg tends to coalesce due to the introduced VBi . The defects created by Bi deficiency effectively weaken the scattering of electrons from the intrinsic VMg and enhance phonon scattering. A peak zT of 1.82 at 773 K and high conversion efficiency of 11.3% at ∆T = 473 K are achieved in the optimized composition of Mg3 (Sb,Bi)2 by tuning the defect combination. This work demonstrates a feasible and effective approach to improving the performance of Mg3 (Sb,Bi)2 as an emerging thermoelectric material. This article is protected by copyright. All rights reserved.

Robust Thermal Neutron Detection by LiInP2 Se6 Bulk Single Crystals.

Direct neutron detection based on semiconductor crystals holds promise to transform current neutron detector technologies and further boosts their widespread applications. It is, however, long impeded by the dearth of suitable materials in the form of sizeable bulk crystals. Here, we have developed high-quality centimeter-sized LiInP2 Se6 single crystals using the Bridgman method and systematically investigated their structure and property characteristics. The prototype detectors fabricated from the crystals demonstrate an energy resolution of 53.7% in response to α-particles generated from an 241 Am source and robust, well-defined response spectra to thermal neutrons that exhibit no polarization or degradation effects under prolonged neutron/γ-ray irradiation. We have also identified the primary mechanisms of Se-vacancy and InLi antisite defects in the carrier trapping process. Such insights are critical for further enhancing the energy resolution of LiInP2 Se6 bulk crystals towards the intrinsic level (∼8.6% as indicated by our chemical vapor transport-grown thin crystals). These results pave the way for practically adopting LiInP2 Se6 single crystals in new-generation solid-state neutron detectors. This article is protected by copyright. All rights reserved.

The Impact of Serum Parameters Associated with Kidney Function on the Short-Term Outcomes and Prognosis of Colorectal Cancer Patients Undergoing Radical Surgery.

Purpose: The current study was designed to investigate the impact of blood urea nitrogen (BUN), serum uric acid (UA), and cystatin (CysC) on the short-term outcomes and prognosis of colorectal cancer (CRC) patients undergoing radical surgery. Methods: CRC patients who underwent radical resection were included from Jan 2011 to Jan 2020 in a single clinical centre. The short-term outcomes, overall survival (OS), and disease-free survival (DFS) were compared in different groups. A Cox regression analysis was conducted to identify independent risk factors for OS and DFS. Results: A total of 2047 CRC patients who underwent radical resection were included in the current study. Patients in the abnormal BUN group had a longer hospital stay (p=0.002) and more overall complications (p=0.001) than that of the normal BUN group. The abnormal CysC group had longer hospital stay (p < 0.01), more overall complications (p=p < 0.01), and more major complications (p=0.001) than the normal CysC group. Abnormal CysC was associated with worse OS and DFS for CRC patients in tumor stage I (p < 0.01). In Cox regression analysis, age (p < 0.01, HR = 1.041, 95% CI = 1.029-1.053), tumor stage (p < 0.01, HR = 2.134, 95% CI = 1.828-2.491), and overall complications (p=0.002, HR = 1.499, 95% CI = 1.166-1.928) were independent risk factors for OS. Similarly, age (p < 0.01, HR = 1.026, 95% CI = 1.016-1.037), tumor stage (p < 0.01, HR = 2.053, 95% CI = 1.788-2.357), and overall complications (p=0.002, HR = 1.440, 95% CI = 1.144-1.814) were independent risk factors for DFS. Conclusion: In conclusion, abnormal CysC was significantly associated with worse OS and DFS at TNM stage I, and abnormal CysC and BUN were related to more postoperative complications. However, preoperative BUN and UA in the serum might not affect OS and DFS for CRC patients who underwent radical resection.

Van der Waals Ferroelectric Semiconductor Field Effect Transistor for In-Memory Computing.

In-memory computing is a highly efficient approach for breaking the bottleneck of von Neumann architectures, i.e., reducing redundant latency and energy consumption during the data transfer between the physically separated memory and processing units. Herein we have designed a in-memory computing device, a van der Waals ferroelectric semiconductor (InSe) based metal-oxide-ferroelectric semiconductor field-effect transistor (MOfeS-FET). This MOfeS-FET integrates memory and logic functions in the same material, in which the out-of-plane (OOP) ferroelectric polarization in InSe is used for data storage and the semiconducting property is used for the logic computation. The MOfeS-FET shows a long retention time with high on/off ratios (>106), high program/erase (P/E) ratios (103), and stable cyclic endurance. Moreover, inverter, programmable NAND, and NOR Boolean logic operations with nonvolatile storage of the results have all been demonstrated using our approach. These findings highlight the potential of van der Waals ferroelectric semiconductor-based MOfeS-FETs in the in-memory computing and their potential of achieving size scaling beyond Moore's law.

The effect of carbon nanoparticles staining on lymph node tracking in colorectal cancer: A propensity score matching analysis.

Purpose: The aim of this study was to evaluate the effect of carbon nanoparticles staining (CNS) on colorectal cancer (CRC) surgery, lymph node tracing and postoperative complications using propensity score matching (PSM). Method: Patients who were diagnosed with CRC and underwent surgery were retrospectively collected from a single clinical center from Jan 2011 to Dec 2021. Baseline characteristics, surgical information and postoperative information were compared between the CNS group and the non-CNS group. PSM was used to eliminate bias. Results: A total of 6,886 patients were enrolled for retrospective analysis. There were 2,078 (30.2%) patients in the CNS group and 4,808 (69.8%) patients in the non-CNS group. After using 1: 1 ratio PSM to eliminate bias, there were 2,045 patients left in each group. Meanwhile, all of their baseline characteristics were well matched and there was no statistical significance between the two groups (P > 0.05). In terms of surgical information and short-term outcomes, the CNS group had less intraoperative blood loss (P < 0.01), shorter operation time (P < 0.01), shorter postoperative hospital stay (P < 0.01), less metastatic lymph nodes (P = 0.013), more total retrieved lymph nodes (P < 0.01), more lymphatic fistula (P = 0.011) and less postoperative overall complications (P < 0.01) than the non-CNS group before PSM. After PSM, the CNS group had less intraoperative blood loss (P = 0.004), shorter postoperative hospital stay (P < 0.01) and more total retrieved lymph nodes (P < 0.01) than the non-CNS group. No statistical difference was found in other outcomes (P > 0.05). Conclusion: Preoperative CNS could help the surgeons detect more lymph nodes, thus better determining the patient's N stage. Furthermore, it could reduce intraoperative blood loss and reduce the hospital stay.

The advanced lung cancer inflammation index is a prognostic factor for gastrointestinal cancer patients undergoing surgery: a systematic review and meta-analysis.

BACKGROUND: The advanced lung cancer inflammation index (ALI) is a comprehensive assessment indicator that can reflect inflammation and nutrition conditions. However, there are some controversies about whether ALI is an independent prognostic factor for gastrointestinal cancer patients undergoing surgical resection. Thus, we aimed to clarify its prognostic value and explore the potential mechanisms. METHODS: Four databases including PubMed, Embase, the Cochrane Library, and CNKI were used for searching eligible studies from inception to June 28, 2022. All gastrointestinal cancers, including colorectal cancer (CRC), gastric cancer (GC), esophageal cancer (EC), liver cancer, cholangiocarcinoma, and pancreatic cancer were enrolled for analysis. We focused on prognosis most in the current meta-analysis. Survival indicators, including overall survival (OS), disease-free survival (DFS), and cancer-special survival (CSS) were compared between the high ALI group and the low ALI group. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was submitted as a supplementary document. RESULTS: We finally included fourteen studies involving 5091 patients in this meta-analysis. After pooling the hazard ratios (HRs) and 95% confidence intervals (CIs), ALI was found to be an independent prognostic factor for both OS (HR = 2.09, I2 = 92%, 95% CI = 1.53 to 2.85, P < 0.01), DFS (HR = 1.48, I2 = 83%, 95% CI = 1.18 to 1.87, P < 0.01), and CSS (HR = 1.28, I2 = 1%, 95% CI = 1.02 to 1.60, P = 0.03) in gastrointestinal cancer. After subgroup analysis, we found that ALI was still closely related to OS for CRC (HR = 2.26, I2 = 93%, 95% CI = 1.53 to 3.32, P < 0.01) and GC (HR = 1.51, I2 = 40%, 95% CI = 1.13 to 2.04, P = 0.006) patients. As for DFS, ALI also has a predictive value on the prognosis of CRC (HR = 1.54, I2 = 85%, 95% CI = 1.14 to 2.07, P = 0.005) and GC (HR = 1.37, I2 = 0%, 95% CI = 1.09 to 1.73, P = 0.007) patients. CONCLUSION: ALI affected gastrointestinal cancer patients in terms of OS, DFS, and CSS. Meanwhile, ALI was a prognostic factor both for CRC and GC patients after subgroup analysis. Patients with low ALI had poorer prognoses. We recommended that surgeons should perform aggressive interventions in patients with low ALI before the operation.

A Cost-effectiveness Analysis of iGlarLixi Versus IDegAsp and Appropriate Price Exploration of iGlarLixi for Type 2 Diabetes Mellitus Patients in China.

BACKGROUND AND OBJECTIVE: The efficacy and safety of iGlarLixi, a fixed-ratio combination (FRC) of basal insulin glargine plus lixisenatide, have been demonstrated in type 2 diabetes mellitus (T2DM) patients. However, no relevant economic analysis of iGlarLixi has been done in China. Thus, the primary objective of this study is to evaluate the cost effectiveness of iGlarLixi versus IDegAsp in Chinese T2DM patients, and then back-calculate the appropriate drug price of iGlarLixi to support its pricing after listing in China. METHODS: The United Kingdom Prospective Diabetes Study Outcome Model 2 (UKPDS OM2) was applied to estimate lifetime health and economic outcomes from the Chinese health-care system perspective. As no head-to-head comparison data are currently available, the baseline cohort characteristics and the initial clinical data for iGlarLixi were derived from the randomized LixiLan-L-China trial. The relative treatment effects for IDegAsp were based on an indirect treatment comparison. Due to the unavailability of iGlarLixi pricing data, the annual medication cost of iGlarLixi was assumed to be equal to that of IDegAsp at the beginning of the study. Afterwards, a break-even analysis using comparator drug price and the willingness-to-pay (WTP) threshold was performed to back-calculate the appropriate drug price of iGlarLixi. One-way sensitivity analysis, scenario analysis and probabilistic sensitivity analysis (PSA) were conducted to assess the robustness of the model. RESULTS: Based on the initial assumption of equal annual medication cost of iGlarLixi and IDegAsp, iGlarLixi was cost effective compared to IDegAsp with an incremental cost-effectiveness ratio (ICER) far below the WTP threshold in Chinese T2DM patients. From the back calculation for the price of iGlarLixi, the annual medication cost of iGlarLixi was $656.96 and $1075.96 to obtain an ICER of iGlarLixi versus IDegAsp close to 1 × GDP and 3 × GDP, respectively. When the discount rate was changed from the base value to 8% (the most sensitive parameter to the model results in one-way sensitivity analysis), the ICER was nearly equal to 1 × GDP and 3 × GDP with the annual medication cost of iGlarLixi decreasing to $590.41 and $865.03, respectively. Thus, iGlarLixi was dominant over IDegAsp with an annual medication cost of $590.41 to $865.03. The findings were robust to one-way sensitivity analysis, PSA and scenario analysis. CONCLUSION: This long-term cost-effectiveness analysis in Chinese T2DM patients indicates that iGlarLixi, assuming equal price to IDegAsp, is cost-effective versus IDegAsp with an ICER far below the WTP threshold. With 1 × GDP and 3 × GDP threshold set we back-calculate the appropriate annual medication cost of iGlarLixi to be $590.41 to $865.03, respectively.

Direct Production of Bio-Recalcitrant Carboxyl-Rich Alicyclic Molecules Evidenced in a Bacterium-Induced Steroid Degradation Experiment.

Carboxyl-rich alicyclic molecules (CRAM) are highly unsaturated compounds extensively distributed throughout aquatic environments and sediments. This molecular group is widely referred to as a major proxy of recalcitrant organic materials, but its direct biosynthesis remains unclear. Steroids are a typical anthropogenic contaminant and have been previously suggested to be precursors of CRAM; however, experimental evidence to support this hypothesis is lacking. Here, a steroid-degrading bacterium, Comamonas testosteroni ATCC 11996, was incubated in a liquid medium supplemented with testosterone (a typical steroid) as the sole carbon source for 90 days. Testosterone-induced metabolites (TIM) were extracted for molecular characterization and to examine the bioavailability during an additional 90-day incubation after inoculation with a natural coastal microbial assemblage. The results showed that 1,775 molecular formulas (MFs) were assigned to TIM using ultrahigh-resolution mass spectrometry, with 66.99% categorized as CRAM-like constituents. A large fraction of TIM was respired or transformed during the additional 90-day seawater incubation; nevertheless, 638 MFs of the TIM persisted or increased during incubation. Among the 638 MFs, 394 were commonly assigned in natural deep seawater samples (depths of 500 to 2,000 m) from the South China Sea. Compared to the catabolites of the well-established testosterone degradation pathway, we compiled a list of bio-refractory MFs and potential chemical structures, some of which shared structural homology with CRAM. These results demonstrated direct microbial production of bio-refractory CRAM from steroid hormones and indicated that some of the biogenic CRAM resisted microbial decomposition, potentially contributing to the aquatic refractory dissolved organic matter (DOM) pool. IMPORTANCE CRAM are an operationally defined DOM group comprising a complex mixture of carboxylated and fused alicyclic structures. This DOM group is majorly characterized as refractory DOM in the marine environment. However, the origins of the complex CRAM remain unclear. In this study, we demonstrated that testosterone (a typical steroid) could be transformed into bio-refractory CRAM by a single bacterial strain and observed that some of the CRAM highly resisted microbial degradation. Through molecular comparison and screening, potential chemical structures of steroid-induced CRAM were suggested. This study established the biological connection between steroids and bio-refractory CRAM, and it provides a novel perspective explaining the fate of terrestrial contaminants in aquatic environments.

Selective Mediastinal Lymph Node Dissection Strategy for Clinical T1N0 Invasive Lung Cancer: A Prospective, Multicenter, Clinical Trial.

INTRODUCTION: We aimed to prospectively evaluate our previously proposed selective mediastinal lymph node (LN) dissection strategy for peripheral clinical T1N0 invasive NSCLC. METHODS: This is a multicenter, prospective clinical trial in China. We set six criteria for predicting negative LN stations and finally guiding selective LN dissection. Consolidation tumor ratio less than or equal to 0.5, segment location, lepidic-predominant adenocarcinoma (LPA), negative hilar nodes (stations 10-12), and negative visceral pleural invasion (VPI) were used separately or in combination as predictors of negative LN status in the whole, superior, or inferior mediastinal zone. LPA, hilar node involvement, and VPI were diagnosed intraoperatively. All patients actually underwent systematic mediastinal LN dissection. The primary end point was the accuracy of the strategy in predicting LN involvement. If LN metastasis occurred in certain mediastinal zone that was predicted to be negative, it was considered as an "inaccurate" case. RESULTS: A total of 720 patients were enrolled. The median number of LN dissected was 15 (interquartile range: 11-20). All negative node status in certain mediastinal zone was correctly predicted by the strategy. Compared with final pathologic findings, the accuracy of frozen section to diagnose LPA, VPI, and hilar node metastasis was 94.0%, 98.9%, and 99.6%, respectively. Inaccurate intraoperative diagnosis of LPA, VPI, or hilar node metastasis did not lead to inaccurate prediction of node-negative status. CONCLUSIONS: This is the first prospective trial validating the specific mediastinal LN metastasis pattern in cT1N0 invasive NSCLC, which provides important evidence for clinical applications of selective LN dissection strategy.

Stretchable PEDOT:PSS/Li-TFSI/XSB Composite Films for Electromagnetic Interference Shielding.

Electromagnetic interference (EMI) shielding materials with stretchability are important for developing wearable and flexible appliances. Herein, lithium bis(trifloromethanesulfonyl)imide (Li-TFSI)-doped poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and carboxylated styrene-butadiene rubber (XSB) latex are used to prepare stretchable EMI shielding composite films of 0.2 mm in thickness. In these films, the doped PEDOT:PSS nanoparticles form tenuous conductive pathways between the hexagonally packed latex particles, resulting in higher EMI shielding efficiency (EMI SE) compared with the films containing traditional dopant ethylene glycol. For the purpose of stretchable EMI shielding, the films containing 6 wt % PEDOT:PSS and 6 wt % Li-TFSI demonstrate EMI SE of 50 and 30 dB (12.4 GHz) at 0 and 100% strains, respectively, being the highest values among the reported shielding composites except for those using liquid metal as the filler. The investigation also provides a simple and environmentally friendly preparation method being highlighted for the development of lightweight stretchable EMI shielding materials for applications in flexible electronics in the near future.

Polymerization-Induced Crystallization of Dopant Molecules: An Efficient Strategy for Room-Temperature Phosphorescence of Hydrogels.

Conventional hydrogels such as polyacrylamide and polyacrylic acid ones seldom exhibit phosphorescences at ambient conditions, which limit their applications as optical materials. We propose and demonstrate here a facile strategy to afford these hydrogels with room-temperature phosphorescence by polymerization-induced crystallization of dopant molecules that results in segregation and confinement of the gel matrix with carbonyl groups and thus clusterization-induced phosphorescence. As a model system, crown ethers (CEs) are dissolved in an aqueous solution of concentrated acrylamide that greatly increases the solubility of CEs. During the polymerization process, CEs crystallize to form large spherulites in the polyacrylamide hydrogel. The crystallization arises from the drastically reduced solubility of CEs after the conversion of monomers to polymers during the gel synthesis. The resultant composite hydrogel with a water content of 67 wt % exhibits extraordinary phosphorescence behavior yet maintains good stretchability and resilience. We found that the partial gel matrix is squeezed and confined by in situ-formed crystals, leading to carbonyl clusters and thus phosphorescence emission. The composite gel shows green phosphorescence with an emission peak at 512 nm and a lifetime of 342 ms. The afterglow emission is detectable by the naked eye for several seconds. This strategy has good universality, as validated in other hydrogels with different polymeric matrices and dopant molecules. The development of hydrogels with good mechanical and phosphorescent properties should merit the design of multifunctional soft machines with applications in biomedical and engineering fields.

Metagenomic and machine learning-aided identification of biomarkers driving distinctive Cd accumulation features in the root-associated microbiome of two rice cultivars.

Developing low-cadmium (Cd) rice cultivars has emerged as a promising avenue for food safety in Cd-contaminated farmlands. The root-associated microbiomes of rice have been shown to enhance rice growth and alleviate Cd stress. However, the microbial taxon-specific Cd resistance mechanisms underlying different Cd accumulation characteristics between different rice cultivars remain largely unknown. This study compared low-Cd cultivar XS14 and hybrid rice cultivar YY17 for Cd accumulation with five soil amendments. The results showed that XS14 was characterized by more variable community structures and stable co-occurrence networks in the soil-root continuum compared to YY17. The stronger stochastic processes in assembly of the XS14 (~25%) rhizosphere community than that of YY17 (~12%) suggested XS14 may have higher resistance to changes in soil properties. Microbial co-occurrence networks and machine learning models jointly identified keystone indicator microbiota, such as Desulfobacteria in XS14 and Nitrospiraceae in YY17. Meanwhile, genes involved in sulfur cycling and nitrogen cycling were observed among the root-associated microbiome of these two cultivars, respectively. Microbiomes in the rhizosphere and root of XS14 showed a higher diversity in functioning, with the significant enrichment of functional genes related to amino acid and carbohydrate transport and metabolism, and sulfur cycling. Our findings revealed differences and similarities in the microbial communities associated with two rice cultivars, as well as bacterial biomarkers predictive of Cd-accumulation capacity. Thus, we provide new insights into taxon-specific recruitment strategies of two rice cultivars under Cd stress and highlight the utility of biomarkers in offering clues for enhancing crop resilience to Cd stresses in the future.

Sam68 promotes osteogenic differentiation of aortic valvular interstitial cells by TNF-α/STAT3/autophagy axis.

Calcified aortic valve disease (CAVD) is a major non-rheumatic heart valve disease in the world, with a high mortality rate and without suitable pharmaceutical therapy due to its complex mechanisms. Src-associated in mitosis 68-KD (Sam68), an RNA binding protein, has been reported as a signaling adaptor in numerous signaling pathways (Huot in Mol Cell Biol, 29(7), 1933-1943, 2009), particularly in inflammatory signaling pathways. The effects of Sam68 on the osteogenic differentiation process of hVICs and its regulation on signal transducer and activator of transcription 3 (STAT3) signaling pathway have been investigated in this study. Human aortic valve samples detection found that Sam68 expression was up-regulated in human calcific aortic valves. We used tumor necrosis factor α (TNF-α) as an activator for osteogenic differentiation in vitro and the result indicated that Sam68 was highly expressed after TNF-α stimulation. Overexpression of Sam68 promoted osteogenic differentiation of hVICs while Sam68 knockdown reversed this effect. Sam68 interaction with STAT3 was predicted by using String database and was verified in this study. Sam68 knockdown reduced phosphorylation of STAT3 activated by TNF-α and the downstream gene expression, which further influenced autophagy flux in hVICs. STAT3 knockdown alleviated the osteogenic differentiation and calcium deposition promoted by Sam68 overexpression. In conclusion, Sam68 interacts with STAT3 and participates in its phosphorylation to promote osteogenic differentiation of hVICs to induce valve calcification. Thus, Sam68 may be a new therapeutic target for CAVD. Regulatory of Sam68 in TNF-α/STAT3/Autophagy Axis in promoting osteogenesis of hVICs.

Metal-Coordinated Dynamics and Viscoelastic Properties of Double-Network Hydrogels.

Biological soft tissues are intrinsically viscoelastic materials which play a significant role in affecting the activity of cells. As potential artificial alternatives, double-network (DN) gels, however, are pure elastic and mechanically time independent. The viscoelasticization of DN gels is an urgent challenge in enabling DN gels to be used for advanced development of biomaterial applications. Herein, we demonstrate a simple approach to regulate the viscoelasticity of tough double-network (DN) hydrogels by forming sulfonate-metal coordination. Owing to the dynamic nature of the coordination bonds, the resultant hydrogels possess highly viscoelastic, mechanical time-dependent, and self-recovery properties. Rheological measurements are performed to investigate the linear dynamic mechanical behavior at small strains. The tensile tests and cyclic tensile tests are also systematically performed to evaluate the rate-dependent large deformation mechanical behaviors and energy dissipation behaviors of various ion-loaded DN hydrogels. It has been revealed based on the systematic analysis that robust strong sulfonate-Zr4+ coordination interactions not only serve as dynamic crosslinks imparting viscoelastic rate-dependent mechanical performances, but also strongly affect the relative strength of the first PAMPS network, thereby increasing the yielding stress σy and the fracture stress at break σb and reducing the stretch ratio at break λb. It is envisioned that the viscoelasticization of DN gels enables versatile applications in the biomedical and engineering fields.

Enhanced Rupture Force in a Cut-Dispersed Double-Network Hydrogel.

The Kirigami approach is an effective way to realize controllable deformation of intelligent materials via introducing cuts into bulk materials. For materials ranging from ordinary stiff materials such as glass, ceramics, and metals to soft materials, including ordinary hydrogels and elastomers, all of them are all sensitive to the presence of cuts, which usually act as defects to deteriorate mechanical properties. Herein, we study the influence of the cuts on the mechanical properties by introducing "dispersed macro-scale cuts" into a model tough double network (DN) hydrogel (named D-cut gel), which consists of a rigid and brittle first network and a ductile stretchable second network. For comparison, DN gels with "continuous cuts" having the same number of interconnected cuts (named C-cut gel) were chosen. The fracture tests of D-cut gel and C-cut gel with different cut patterns were performed. The fracture observation revealed that crack blunting occurred at each cut tip, and a large wrinkle-like zone was formed where the wrinkles were parallel to the propagation direction of the cut. By utilizing homemade circular polarizing optical systems, we found that introducing dispersed cuts increases the rupture force by homogenizing the stress around the crack tip surrounding every cut, which reduces stress concentration in one certain cut. We believe this work reveals the fracture mechanism of tough soft materials with a kirigami cut structure, which should guide the design of advanced soft and tough materials along this line.