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Here, we successfully modulated the anisotropic photoresponse by constructing halide perovskites with different quantum well (QW) thicknesses. The results show that the narrowed halide perovskite QWs exhibit a larger photocurrent anisotropy ratio ω. The dependence of the anisotropic photoresponse on the thickness of the QWs provides a distinct means for the design of high-performance polarization-sensitive photodetectors. [ABSTRACT FROM AUTHOR]

The impact of halogens on chiral crystal structures and properties has been a significant focus. In this study, we utilize protonated R/S-tetrahydro-2H-pyran-3-ammonium (R/S-3ATHP) as an organic cation to synthesize four pairs of one-dimensional (1D) helical chiral hybrid metal halides. The replacement of the halogen anions (X = Cl−, Br−, and I−) and variation of the cation/anion ratio induce changes in the 1D chain packing mode and helicity of the inorganic components in the crystals. Notably, the Br-based chiral hybrid metal halides exhibit two structures, analogous to the Cl (zigzag, z-) and I (linear, l-) counterparts. Structural variations resulting from halogen adjustments further modulate the chiroptical activity, semiconducting, and photoluminescence properties of the crystals. Particularly noteworthy is the helicity of the [PbX6] octahedral-based chains that is significantly influenced by the asymmetric hydrogen bonding interactions which are determined by the halogens and the number of organic cations. The regular change observed in gCD values: z-(R/S-3ATHP)3PbBr5 > z-(R/S-3ATHP)3PbCl5 > l-(R/S-3ATHP)PbI3 > l-(R/S-3ATHP)PbBr3, is correlated with helicity of the helical 1D chains in the crystals, indicating that more helicity corresponds to stronger chiroptical activity. This work establishes a model system for comprehending the interplay between halogens and structural diversity as well as helicity and chiroptical activity, contributing to a deeper understanding of these relationships in related fields. [ABSTRACT FROM AUTHOR]

Background: The CRC‐VTE trial conducted in China revealed a significant occurrence of venous thromboembolism (VTE) in patients following colorectal cancer (CRC) surgery, raising concerns about implementing thromboprophylaxis measures. The present study aimed to identify and analyze inappropriate aspects of current thromboprophylaxis practices. Methods: This study performed an analysis of the CRC‐VTE trial, a prospective multicenter study that enrolled 1836 patients who underwent CRC surgery. The primary objective was to identify independent risk factors for VTE after CRC surgery using multivariate logistic regression analysis. Furthermore, among the cases in which VTE occurred, the appropriateness of thromboprophylaxis was assessed based on several factors, including pharmacologic prophylaxis, time to initiate prophylaxis, drug selection, drug dosage, and duration of pharmacologic prophylaxis. Based on the analysis of the current state of thromboprophylaxis and relevant clinical guidelines, a modified Delphi method was used to develop a clinical pathway for VTE prophylaxis after CRC surgery. Results: In this analysis of 1836 patients, 205 (11.2%) were diagnosed with VTE during follow‐up. The multifactorial analysis identified several independent risk factors for VTE, including age (≥70 years), female sex, varicose veins in the lower extremities, intraoperative blood transfusion, and the duration of immobilization exceeding 24 h. None of the patients diagnosed with VTE in the CRC trial received adequate thromboprophylaxis. The main reasons for this inappropriate practice were the omission of thromboprophylaxis, delayed initiation, and insufficient duration of thromboprophylaxis. We developed a specialized clinical pathway for thromboprophylaxis after CRC surgery to address these issues. Conclusions: This study offers a comprehensive nationwide evaluation of existing thromboprophylaxis practices in patients after CRC surgery in China. A specialized clinical pathway was developed to address the identified gaps and improve the quality of care. This clinical pathway incorporates explicit, tailored, detailed recommendations for thromboprophylaxis after CRC surgery. [ABSTRACT FROM AUTHOR]

Belowground parameters, e.g. root production and dynamics, play a pivotal role in evaluating the restoration degree of degraded grasslands. However, it remains unclear how roots respond to the combined restoration measures. To investigate root responses to different restoration treatments, a field experiment was conducted in a degraded Songnen meadow from 2013 to 2014. The treatments included: free grazing (FG), no ploughing (NP), only ploughing (OP), ploughing and fertilizer (PF), ploughing and mulching (PM), ploughing with fertilizer and mulching (PFM). Our results showed the seasonal dynamics pattern of roots was a unimodal pattern, which mainly was influenced by precipitation rather than restoration measures. The impacts of different restoration measures on root production were dependent on precipitation. In 2013, compared with FG, only PFM significantly increased root production by 242.34% (0–10 cm) and 90.8% (10–20 cm), which was mainly attributed to the increase of aboveground net primary production, soil moisture and root numbers. However, restoration measures had minor effects on root production in 2014. Root turnover ranged from 0.47 to 0.78 yr−1 and was not significantly changed by different restored measures. This is because the dominant annual species, Chloris virgata , exhibited relatively small changes in root turnover across different plots. Moreover, PFM improved soil conditions, leading to increased root lifespan and survival rate. Our results suggest that the combined measures are an effective way to accelerate belowground restoration in the degraded Songnen meadow. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) with polychromatic colors has been widely studied due to its great applications in chiroptical, optoelectronics, and spintronics. However, the realization of white CPL in single‐component solid‐state materials remains a great challenge and suffers from the incompatibility between high efficient luminescence and large asymmetric discrimination. Here, by exploiting self‐trapped exciton mechanism and chirality induction strategy, a pair of 1D chiral perovskites, (RR/SS‐DMPZ)PbBr4 (where DMPZ = cis‐2,5‐dimethylpiperazine divalent cation), is reported to achieve white CPL with both high quantum yield of 28.4% and large photoluminescence asymmetry factor |glum| of 2.32 × 10−2. The crystal structures are featured by 1D double‐chain structure composed of distorted octahedra with short PbPb distances as the structural origin of the high photoluminescence yield. The high |glum| value is caused by efficient chiral induction due to the multiple hydrogen bonds between the chiral host composed of the enantiopure organic cations containing two stereocenters and the inorganic emitting guest. The self‐trapped exciton emission mechanism is demonstrated by density functional theory calculations and variable‐temperature photoluminescence and femtosecond‐transient absorption spectroscopy studies. The photo‐luminescent white light‐emitting diodes exhibit good stability and can be used as single‐component white light emitters. This work provides applicable strategies to explore single‐component white CPL emitters. [ABSTRACT FROM AUTHOR]

Mn2+ doped colloidal three‐dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one‐dimensional (1D) hybrid perovskite of [AEP]PbBr5 ⋅ H2O (AEP=N‐aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn2+ doping strategy. Significantly, the series of Mn2+‐doped 1D [AEP]PbBr5 ⋅ H2O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn2+‐doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn2+‐doped 1D perovskite as excellent down‐converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low‐dimensional perovskites but also opens a new way to rationally design high‐performance broadband light emitting perovskites for solid‐state lighting and displaying devices. [ABSTRACT FROM AUTHOR]

Recently, low-dimensional organic–inorganic hybrid metal halides have attracted considerable attention in solid-state optical application fields, especially in white-light emitting diodes (WLEDs) owing to intrinsic broadband luminescence performances. Herein, by selecting different types of organic cations as a structural decoration strategy, we designed a series of new 1D hybrid halides of A2Pb3Br10 (A = NPM, DMPDA, TMEN) based on same [Pb3Br10]4− chains composed of edge-shared [Pb3Br12]6− trimers. The low-dimensional crystal lattice results in the formation of self-trapped excitons, which leads to broadband light emissions covering the entire visible region for all A2Pb3Br10 homologues. Specifically, compound 1 exhibits yellowish-white light emission (0.34, 0.45) with a photoluminescence quantum efficiency of 2.51%. Both compounds 2 and 3 show bluish-white light emissions centered at 438 nm and 440 nm, respectively, with high color rendering index (CRI) of 96, which belongs to one of the highest values to date. The intrinsic broadband white light emissions enable them as promising candidates for single-component white-light emitting materials. [ABSTRACT FROM AUTHOR]

Root water uptake (RWU) is a unique process whereby plants obtain water from soil, and it is essential for plant survival. The mechanisms of RWU are well understood, but their parameterization and simulation in current Land Surface Models (LSMs) fall short of the requirements of modern hydrological and climatic modelling research. Though various RWU functions have been proposed for potential use in LSMs, none was proven to be applicable for dryland ecosystems where drought was generally the limiting factor for ecosystem functioning. This study investigates the effect of root distribution on the simulated surface energy fluxes by incorporating the observed vertical root distribution. In addition, three different RWU functions were integrated into the Common Land Model (CLM) in place of the default RWU function. A comparison of the modified model's results with the measured surface energy fluxes measured by eddy covariance techniques in a Central Asian desert shrub ecosystem showed that both RWU function and vertical root distribution were able to significantly impact turbulent fluxes. Parameterizing the root distribution based on in-situ measurement and replacing the default RWU function with a revised version significantly improved the CLM's performance in simulating the latent and sensible heat fluxes. Sensitivity analysis showed that varying the parameter values of the revised RWU function did not significantly impact the CLM's performance, and therefore, this function is recommended for use in the CLM in Central Asian desert ecosystems and, possibly, other similar dryland ecosystems. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Integrating multiple switching behaviors in a single material is conducive to the development of smart devices, but still faces challenges, especially in finding new types of multiresponsive materials. Hybrid metal halides have been becoming promising candidates with the potential to exhibit changes in various physical and chemical properties upon structural phase transitions. Herein, a pair of enantiomers (R/S‐3‐OHPD)PbI3 (1R/1S; 3‐HOPD = 3‐hydroxypiperidine cation) is reported to show multichannel switching behaviors around room temperature triggered by a combined order‐disorder and displacive type phase transition that arouses a large lattice reorganization and shape change of the crystals. Owing to the inherent chiral, noncentrosymmetric, and semiconducting characteristics of the compounds, five other switching behaviors are realized besides the macroscopic deformation, that is, enthalpy, dielectric permittivity, photoluminescence, circularly polarized light excited photoluminescence, and photoelectric response. This study provides an exciting example of phase transition crystals for the development of integrated multifunctional materials. [ABSTRACT FROM AUTHOR]

Background: Venous thromboembolism (VTE) is a common and serious complication after colorectal cancer (CRC) surgery. Few large-sample studies have reported VTE incidence and management status after CRC surgery in China. This study aimed to investigate the incidence and prevention of VTE in Chinese patients after CRC surgery, identify risk factors for developing VTE, and construct a new scoring system for clinical decision-making and care planning., Methods: Participants were recruited from 46 centers in 17 provinces in China. Patients were followed up for 1 month postoperatively. The study period was from May 2021 to May 2022. The Caprini score risk stratification and VTE prevention and incidence were recorded. The predictors of the occurrence of VTE after surgery were identified by multivariate logistic regression analysis, and a prediction model (CRC-VTE score) was developed., Results: A total of 1836 patients were analyzed. The postoperative Caprini scores ranged from 1 to 16 points, with a median of 6 points. Of these, 10.1% were classified as low risk (0-2 points), 7.4% as moderate risk (3-4 points), and 82.5% as high risk (≥5 points). Among these patients, 1210 (65.9%) received pharmacological prophylaxis, and 1061 (57.8%) received mechanical prophylaxis. The incidence of short-term VTE events after CRC surgery was 11.2% (95% CI 9.8-12.7), including deep venous thrombosis (DVT) (11.0%, 95% CI 9.6-12.5) and pulmonary embolism (PE) (0.2%, 95% CI 0-0.5). Multifactorial analysis showed that age (≥70 years), history of varicose veins in the lower extremities, cardiac insufficiency, female sex, preoperative bowel obstruction, preoperative bloody/tarry stool, and anesthesia time at least 180 min were independent risk factors for postoperative VTE. The CRC-VTE model was developed from these seven factors and had good VTE predictive performance ( C -statistic 0.72, 95% CI 0.68-0.76)., Conclusions: This study provided a national perspective on the incidence and prevention of VTE after CRC surgery in China. The study offers guidance for VTE prevention in patients after CRC surgery. A practical CRC-VTE risk predictive model was proposed., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

Mn 2+ doped colloidal three-dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one-dimensional (1D) hybrid perovskite of [AEP]PbBr 5  ⋅ H 2 O (AEP=N-aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn 2+ doping strategy. Significantly, the series of Mn 2+ -doped 1D [AEP]PbBr 5  ⋅ H 2 O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn 2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn 2+ -doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn 2+ -doped 1D perovskite as excellent down-converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low-dimensional perovskites but also opens a new way to rationally design high-performance broadband light emitting perovskites for solid-state lighting and displaying devices., (© 2021 Wiley-VCH GmbH.)

Recently, 2D organic-inorganic hybrid lead halide perovskites have attracted intensive attention in solid-state luminescence fields such as single-component white-light emitters, and rational optimization of the photoluminescence (PL) performance through accurate structural-design strategies is still significant. Herein, by carefully choosing homologous aliphatic amines as templates, isotypical perovskites [DMEDA]PbCl 4 (1, DMEDA=N,N-dimethylethylenediamine) and [DMPDA]PbCl 4 (2, DMPDA=N,N-dimethyl-1,3-diaminopropane) having tunable and stable broadband bluish white emission properties were rationally designed. The subtle regulation of organic cations leads to a higher degree of distortion of the 2D [PbCl 4 ] 2- layers and enhanced photoluminescence quantum efficiencies (<1 % for 1 and 4.9 % for 2). The broadband light emissions could be ascribed to self-trapped excitons on the basis of structural characterization, time-resolved PL, temperature-dependent PL emission, and theoretical calculations. This work gives a new guidance to rationally optimize the PL properties of low-dimensional halide perovskites and affords a platform to probe the structure-property relationship., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To investigate the effect of the RNAi and the chemotherapy drugs nolatrxed on the expression of thymidylate synthase(TS) and the growth of the colorectal carcinoma LOVO cells., Methods: The siRNA was constructed targeting the human TS gene, and then transfected into the human colorectal cancer LOVO cells. RT-PCR and Western blot technique were used to observe the TS gene and protein expression levels, and MTT was used to detect cell proliferation after silencing the TS gene. In addition, siRNA and nolatrxed were applied to the LOVO cells to observe the TS protein expression and cell growth., Results: TS siRNA significantly reduced the expression of TS gene and protein in LOVO cells, and inhibited cell growth. The IC50 value of LOVO cells was (1.46±0.25) μmol/L in TS siRNA combined with nolatrexed group, (6.81±0.31) μmol/L in the negative control group, and (6.47±0.43) μmol/L in the single nolatrexed group. After treatment of TS siRNA combined with nolatrexed on LOVO cells for 36 hours, the apoptosis index was higher than that in single TS siRNA and nolatrexed[(62.12±0.89)% vs.(21.56±0.67)% and(40.51±0.83)%, both P<0.05]., Conclusion: TS siRNA can partly suppress the expression of TS gene in LOVO cells, inhibit cell proliferation, promote cell apoptosis and enhance cell sensitivity to apoptosis induced by nolatrexd.