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The novel antiperovskites exhibit a low dimensional electronic structure, making them a potential luminous material. Herein, our study explored the new and ecofriendly antiperovskites to identify six promising luminous candidates.

Compared with their three-dimensional (3D) counterparts, low-dimensional metal halide perovskites (2D and quasi-2D; B

Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. A remaining challenge is to combine high mechanical robustness with good electrical conduction, especially when patterned at small feature sizes. We develop a molecular engineering strategy based on a topological supramolecular network, which allows for the decoupling of competing effects from multiple molecular building blocks to meet complex requirements. We obtained simultaneously high conductivity and crack-onset strain in a physiological environment, with direct photopatternability down to the cellular scale. We further collected stable electromyography signals on soft and malleable octopus and performed localized neuromodulation down to single-nucleus precision for controlling organ-specific activities through the delicate brainstem.

Chirality, an intrinsic property of nature, has received increased attention in chemistry, biology, and materials science because it can induce optical rotation, ferroelectricity, nonlinear optical response, and other unique properties. Here, by introducing chirality into hybrid rare-earth double perovskites (HREDPs), we successfully designed and synthesized a pair of enantiomeric three-dimensional (3D) HREDPs, [(

A.G. and A.S. acknowledge funding from the TomKat Center for Sustainable Energy at Stanford University and the StorageX initiative. A.S. and S.T.M.T. gratefully acknowledge support from the National Science Foundation Award CBET #1804915. T.J.Q. and G.L. acknowledge support from the NSF Graduate Research Fellowship Program under grant DGE-1656518. Part of this work was performed at the Stanford Nanofabrication Facilities (SNF) and Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation as part of the National Nanotechnology Coordinated Infrastructure under award ECCS-1542152. The authors acknowledge financial support from KAUST, including the Office of Sponsored Research (OSR) award nos. OSR-2018-CRG/CCF-3079, OSR-2019-CRG8-4086, and OSR-2018-CRG7-3749. The authors acknowledge funding from an ERC Synergy Grant SC2 (610115). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515.

Past decades have witnessed swine as the common sources of Salmonella enterica infections. Nevertheless, how Salmonella enterica entered food supply chains and caused foodborne outbreaks remains to be excluded. By analysis of 718 publicly Salmonella enterica isolates, we demonstrated that Euramerica act as the centralized sourcing for the global spread of Salmonella enterica which origins at the pinnacle of pork production. Specifically, the lineage of Salmonella Choleraesuis lend geographic support for their dispersal from Euramerica centralized origins. We used the generalized linear model to quantify the relative contributions of potential explanatory variables to the global transmission of Salmonella enterica. The global pork trade may act as the key driver for the geographic dispersal of Salmonella enterica over the world. In addition, the application of antimicrobials over the past 80 years may also exert a large impact on the evolution of Salmonella enterica genomics. Taken together, our findings provided the global lineage evolution of Salmonella enterica. Further investigation and potential intervention are needed to identify the global spread of Salmonella enterica over the world.

Supported catalysts have exhibited excellent performance in various reactions. However, the rational design of supported catalysts with high activity and certain selectivity remains a great challenge because of the complicated interfacial effects. Using recently emerged two-dimensional materials supported dual-atom catalysts (DACs@2D) as a prototype, we propose a simple and universal descriptor based on inherent atomic properties (electronegativity, electron type, and number), which can well evaluate the complicated interfacial effects on the electrochemical reduction reactions (i.e., CO

Objective: To compare the clinical efficacy of modified single-incision technique without special extraperitoneal PORT with that of transperitoneal multi-incision robot-assisted laparoscopic radical prostatectomy, and to explore the feasibility and safety of this innovative technique. Method: A retrospective analysis was performed on 259 cases who received robot-assisted laparoscopic radical prostatectomy in the Robot Minimally Invasive Center of Sichuan Provincial People's Hospital from September 2018 to August 2021. Among them, there were 147 cases with no special PORT extraperitoneal single incision (Group A) and 112 cases with multiple incisions by transperitoneal method(Group B). The differences in age, PSA level, Gleason score, prostate volume, body mass index, clinical stage, lower abdominal operation history, and lymph node dissection ratio between the two groups were not statistically significant (P > 0.05). All operations were performed by the same operator. Results: In this study, all the 259 operations were completed successfully and there was no conversion. There was no significant difference in transperitoneal blood loss, postoperative hospital stay, positive rate of incision margin, indwelling time of urinary catheter, satisfaction rate of immediate urine control, satisfaction rate of urine control 3 months after operation, positive rate of postoperative lymph node pathology and postoperative pathological stage between the two groups (P > 0.05). There were significant differences in operation time, postoperative exhaust time and incision length (P < 0.05). Conclusion: Modified extraperitoneal no special PORT single incision technique is safe and feasible for robot-assisted laparoscopic radical prostatectomy, and its curative effect is similar to that of transperitoneal multi-incision RARP. It has the advantages of short operation time, less impact on gastrointestinal tract and more beautiful incision. The long-term effect of treatment needs to be further confirmed by prospective studies.

The present study was targeted at investigating the effects of long intergenic non-protein coding RNA 1094 on breast cancer (BC) cell proliferation, apoptosis, and cell cycle and its related mechanism. In this study, Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) were conducted to detect the expressions of LINC01094, microRNA (miRNA, miR)-340-5p, and E2F transcription factor 3 (E2F3) in BC tissues and cells. With transfection, LINC01094 and miR-340-5p expressions were selectively up-regulated or down-regulated in BC cell lines, and then cell proliferation, cell cycle, and apoptosis were examined by cell counting kit-8 (CCK-8), 5-bromo-2ʹ-deoxyuridine (BrdU), and flow cytometry assays. Bioinformatics was utilized to predict the targeted relationships between miR-340-5p and LINC01094, as well as miR-340-5p and E2F3 mRNA 3ʹ-untranslated region (3ʹUTR), and RNA immunoprecipitation (RIP) assay and dual-luciferase reporter gene assay were employed to validate them. It was revealed that, LINC01094 expression was enhanced in BC cells and tissues, and LINC01094 overexpression promoted BC cell proliferation, accelerated cell cycle progression, and inhibited apoptosis while knocking down LINC01094 worked oppositely. LINC01094 directly targeted miR-340-5p and negatively regulated its expression in BC cells. Besides, E2F3 was substantiated to be the target gene of miR-340-5p, and E2F3 expression could be indirectly and positively modulated by LINC01094. All in all, LINC01094 promotes BC cell proliferation and cell cycle progression and inhibits apoptosis via modulating miR-340-5p/E2F3 molecular axis.

Transient electronics are a rapidly emerging field due to their potential applications in the environment and human health. Recently, a few studies have incorporated acid-labile imine bonds into polymer semiconductors to impart transience; however, understanding of the structure-degradation property relationships of these polymers is limited. In this study, we systematically design and characterize a series of fully degradable diketopyrrolopyrrole-based polymers with engineered sidechains to investigate the impact of several molecular design parameters on the degradation lifetimes of these polymers. By monitoring degradation kinetics via ultraviolet-visible spectroscopy, we reveal that polymer degradation in solution is aggregation-dependent based on the branching point and

Pancreatic stellate cells (PSCs) are the primary cell components of pancreatic cancer (PC) and are involved in tumor growth, metastasis and resistance. However, the role and the mechanism of PSCs in gemcitabine (GEM) resistance to PC still need more investigation. We found that CXCL12 mRNA and secreted CXCL12 protein were higher in PSCs after GEM treatment. The conditioned medium (CM) from GEM-treated PSCs reduced the GEM sensitivity of PC cells. Blocking of CXCL12 in CM by anti-CXCL12 antibody partly restored the GEM sensitivity of PC cells. Blocking of CXCL12 decreased glucose consumption, lactate production, ECAR, and glycolysis-related gene expression in PC cells. The PI3K/AKT/mTOR pathway was activated by the binding of CXCL12 and CXCR4. Moreover, CXCR4 mRNA and protein expressions in PC cells were increased after GEM treatment. Our results indicated the cross-talk between PSCs and PC cells during GEM chemotherapy. CXCL12 secreted by PSCs reduces GEM sensitivity of PC cells by binding to CXCR4 and activating PI3K/AKT/mTOR-glycolysis pathway in PC. Our findings would lay the foundation for solving GEM resistance in PC.

We report how the nanoconfined environment, introduced by the mechanical bonds within an electrochemically switchable bistable [2]rotaxane, controls the rotation of a fluorescent molecular rotor, namely an 8-phenyl-substituted boron dipyrromethene (BODIPY). The electrochemical switching of the bistable [2]rotaxane induces changes in the ground-state co-conformation and in the corresponding excited-state properties of the BODIPY rotor. In the starting redox state, when no external potential is applied, the cyclobis(paraquat-p-phenylene) (CBPQT⁴⁺) ring component encircles the tetrathiafulvalene (TTF) unit on the dumbbell component, leaving the BODIPY rotor unhindered and exhibiting low fluorescence. Upon oxidation of the TTF unit to a TTF²⁺ dication the CBPQT⁴⁺ ring is forced toward the molecular rotor leading to an increased energy barrier for the excited-state to rotate the rotor into the state with the high non-radiative rate constant, resulting in an overall 3.4-fold fluorescent enhancement. On the other hand, when the solvent polarity is high enough to stabilize the excited charge transfer state between the BODIPY rotor and the CBPQT⁴⁺ ring, the movement of the ring towards the BODIPY rotor produces an unexpectedly strong fluorescent signal decrease as the result of the photoinduced electron transfer from the BODIPY rotor to the CBPQT⁴⁺ ring. The nanoconfinement effect introduced by mechanical bonding can effectively lead to the modulation of the physicochemical properties as observed in this bistable [2]rotaxane. On account of the straightforward synthetic strategy and the facile modulation of switchable electrochromic behavior, our approach could pave the way for the development of new stimuli-responsive materials based on mechanically interlocked molecules for future electro-optical applications, such as sensors, molecular memories and molecular logic gates.

Property-oriented material design is a persistent pursuit for material scientists. Recently, machine learning (ML) as a powerful new tool has attracted worldwide attention in the material design field. Based on statistics instead of solving physical equations, ML can predict material properties faster with lower cost. Because of its data-driven characteristics, the quantity and quality of material data become the keys to the practical applications of this technique. In this Perspective, problems caused by lack of data and diversity of data are discussed. Various approaches, including high-throughput calculations, database construction, feedback loop algorithms, and better descriptors, have been exploited to address these problems. It is expected that this Perspective will bring data itself to the forefront of ML-based material design.

Excited-state symmetry-breaking charge separation (SB-CS) can offer an efficient pathway to solar energy capture and conversion. We synthesized a series of 1,6,7,12-tetrakis(4-t-butylphenoxy)peryle...

We study high‐dimensional covariance/precision matrix estimation under the assumption that the covariance/precision matrix can be decomposed into a low‐rank component ? and a diagonal component ? . The rank of ? can either be chosen to be small or controlled by a penalty function. Under moderate conditions on the population covariance/precision matrix itself and on the penalty function, we prove some consistency results for our estimators. A block‐wise coordinate descent algorithm, which iteratively updates ? and ? , is then proposed to obtain the estimator in practice. Finally, various numerical experiments are presented; using simulated data, we show that our estimator performs quite well in terms of the Kullback–Leibler loss; using stock return data, we show that our method can be applied to obtain enhanced solutions to the Markowitz portfolio selection problem. The Canadian Journal of Statistics 48: 308–337; 2020 © 2019 Statistical Society of Canada

Polymer aggregation and crystallization behavior play a crucial role in the performance of all-polymer solar cells (all-PSCs). Gaining control over polymer self-assembly via molecular design to influence bulk-heterojunction active-layer morphology, however, remains challenging. Herein, we show a simple yet effective way to modulate the self-aggregation of the commonly used naphthalene diimide (NDI)-based acceptor polymer (N2200), by systematically replacing a certain amount of alkyl side-chains with compact bulky side-chains (CBS). Specifically, we have synthesized a series of random copolymer (PNDI-CBSx) with different molar fractions (x = 0-1) of the CBS units and have found that both solution-phase aggregation and solid-state crystallinity of these acceptor polymers are progressively suppressed with increasing x as evidenced by UV-vis absorption, photoluminescence (PL) spectroscopies, thermal analysis, and grazing incidence X-ray scattering (GIWAXS) techniques. Importantly, as compared to the highly self-aggregating N2200, photovoltaic results show that blending of more amorphous acceptor polymers with donor polymer (PBDB-T) can enable all-PSCs with significantly increased PCE (up to 8.5%). The higher short-circuit current density (Jsc) results from the smaller polymer phase-separation domain sizes as evidenced by PL quenching and resonant soft X-ray scattering (R-SoXS) analyses. Additionally, we show that the lower crystallinity of the active layer is less sensitive to the film deposition methods. Thus, the transition from spin-coating to solution coating can be easily achieved with no performance losses. On the other hand, decreasing aggregation and crystallinity of the acceptor polymer too much reduces the photovoltaic performance as the donor phase-separation domain sizes increases. The highly amorphous acceptor polymers appear to induce formation of larger donor polymer crystallites. These results highlight the importance of a balanced aggregation strength between the donor and acceptor polymers to achieve high-performance all-PSCs with optimal active layer film morphology.

Next-generation light-emitting displays on skin should be soft, stretchable and bright

Strategies to improve stretchability of polymer semiconductors, such as introducing flexible conjugation-breakers or adding flexible blocks, usually result in degraded electrical properties. In this work, we propose a concept to address this limitation, by introducing conjugated rigid fused-rings with optimized bulky side groups and maintaining a conjugated polymer backbone. Specifically, we investigated two classes of rigid fused-ring systems, namely, benzene-substituted dibenzothiopheno[6,5-b:6',5'-f]thieno[3,2-b]thiophene (Ph-DBTTT) and indacenodithiophene (IDT) systems, and identified molecules displaying optimized electrical and mechanical properties. In the IDT system, the polymer PIDT-3T-OC12-10% showed promising electrical and mechanical properties. In fully stretchable transistors, the polymer PIDT-3T-OC12-10% showed a mobility of 0.27 cm2 V-1 s-1 at 75% strain and maintained its mobility after being subjected to hundreds of stretching-releasing cycles at 25% strain. Our results underscore the intimate correlation between chemical structures, mechanical properties, and charge carrier mobility for polymer semiconductors. Our described molecular design approach will help to expedite the next generation of intrinsically stretchable high-performance polymer semiconductors.

Mixed double halide organic–inorganic perovskites (MDHOIPs) exhibit both good stability and high power conversion efficiency and have been regarded as attractive photovoltaic materials. Nevertheless, due to the complexity of structures, large-scale screening of thousands of possible candidates remains a great challenge. In this work, advanced machine learning (ML) techniques and first-principles calculations were combined to achieve a rapid screening of MDHOIPs for solar cells. Successfully, 204 stable lead-free MDHOIPs with optimal bandgaps were selected out of 11 370 candidates. The accuracy of ML models for perovskite structure formability and bandgap is over 94% and 97%, respectively. Moreover, representative MDHOIP candidates, MA2GeSnI4Br2 and MA2InBiI2Br4, stand out with suitable direct bandgaps, light carrier effective masses, small exciton binding energies, strong visible light absorption, and good stability against decomposition.

Background Hydatid cysts are parasitic zoonoses that often occur in the liver. Pancreatic hydatid cysts are very rare and are usually misdiagnosed as pancreatic cystadenomas. At present, surgical resection combined with albendazole administration is the standard treatment for pancreatic hydatid cysts. However, making accurate preoperative diagnoses and avoiding intraoperative cystic rupture are challenges for surgeons. Case presentation A 28-year-old woman from the pastoral area presented to the surgical office complaining of abdominal pain and new-onset jaundice that began 9 days earlier. An enhanced computed tomography scan demonstrated a 6.0 × 5.3 cm pancreatic head cystic mass that compressed the common bile duct and induced choledochectasia. The preoperative diagnosis was pancreatic head cystadenoma, and laparotomic pancreaticoduodenectomy was initiated successfully. The intra- and postoperative diagnosis was pancreatic hydatid cyst. The patient was discharged uneventfully 7 days after the operation. A 1-year course of albendazole (15 mg/kg/day) was admitted. Conclusion Pancreatic hydatid cysts are rare and often misdiagnosed as other types of cysts. History of living in an area in which the causative organism is endemic and positive anti-echinococcus IgG antibody status could help with the diagnosis. Radical resection combined with oral albendazole administration is the standard treatment for pancreatic hydatid cysts. Avoiding perioperative cystic rupture and abdominal echinococcosis implantation metastasis is crucial for the success of the operation.