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High‐performance light‐emitting/detecting bifunctional optoelectronic devices based on halide perovskites are hindered by the less efficient carrier transport and radiative recombination processes. The density of defects (i.e., surface and bulk defects) is the main factor affecting carrier transport, radiation recombination, and determining performance in perovskites. Therefore, techniques to effectively regulate defects are highly needed. Here, a convenient and effective strategy, electrical doping, is proposed to flexibly regulate defect density, resulting in dramatically enhanced light‐emitting (i.e., fluorescence and carrier lifetime) and light‐detecting performance (i.e., hole mobility, photo‐responsivity, and photo‐detectivity) simultaneously. An improved carrier transport model in CH3NH3PbBr3 (MPB) single‐crystal thin‐film (SCTF) is proposed to elucidate the regulation mechanism of defects and carrier transport under electrical doping. These results show that the surface defect density can be effectively reduced by 47.49% under optimal electrical poling intensity (0.168 V µm−1), and photoluminescence intensity and carrier lifetime can be increased by 259% and 89.98%, respectively. Furthermore, planar MPB SCTF photodetector exhibits hole mobility increased by 14.97%, photo‐responsivity increased by 82.78%, and photo‐detectivity increased by 868% at 0.168 V µm−1. Particularly, a record photo‐detectivity of 3.53 × 1013 Jones is achieved under electrical doping. This study provides guidance for flexibly adjusting defect density and optimizing perovskite SCTFs light‐emitting/detecting bifunctional devices. [ABSTRACT FROM AUTHOR]

Background: Benefiting from increased life expectancy and improved perioperative management, more elderly patients with pancreatic head cancer (PHC) underwent pancreaticoduodenectomy (PD). However, individualized predictive models for the safety and efficacy of PD is still lacking. this study aimed to developed three safety‐ and efficacy‐related risk calculators for elderly (> = 65 years) PHC patients. Methods: This study was designed with two research cohorts, namely, the training cohort and the validation cohort, and comprises four general steps: (1) Risk factors were analyzed for the incidence of postoperative complications, cancer‐specific survival (CSS), and overall survival (OS) in the training cohort (N = 271) using logistic and Cox‐regression analysis. (2) Nomograms were then plotted based on the above results. (3) The accuracy of the developed nomogram models was then verified with the validation cohort (N = 134) data using consistency index (C‐index) and calibration curves. (4) We then evaluated the efficacy of these nomograms using decision curve analysis (DCA) in both the training and validation cohorts, and ultimately constructed three online calculators based on these nomograms. Results: We identified ASA, diabetes, smoking, and lymph node invasion as predisposing risk factors for postoperative complications, and the predictive factors that affected both OS and CSS were ASA, diabetes, BMI, CA19‐9 level, and tumor diameter. By integrating the above risk factors, we constructed three nomograms on postoperative complication, CSS, and OS. The C‐index for complication, CSS, and OS were 0.824, 0.784, and 0.801 in the training cohort and 0.746, 0.718, and 0.708 in the validation cohort. Moreover, the validation curves and DCA demonstrated good calibration and robust compliance in both training and validation cohorts. We then developed three web calculators (https://caiming.shinyapps.io/CMCD/, https://caiming.shinyapps.io/CMCSS/, and https://caiming.shinyapps.io/CMOS/) to facilitate the use of the nomograms. Conclusions: The calculators demonstrated promising performance as an tool for predicting the safety and efficacy of PD in elderly PHC patients. [ABSTRACT FROM AUTHOR]

Objective: Clinical practitioners face a significant challenge in maintaining a healthy balance between overtreatment and missed diagnosis in the management of intraductal papillary mucinous neoplasm (IPMN). The current study aimed to identify significant risk factors of malignant IPMN from a series of clinical and radiological parameters that are widely available and noninvasive and develop a method to individually predict the risk of malignant IPMN to improve its management. Methods: We retrospectively investigated 168 patients who were pathologically diagnosed with IPMN after individualized pancreatic resection between June, 2012 and December, 2020. Independent predictors determined using both univariate and multivariate analyses to construct a predictive model. The discriminatory power of the nomogram was assessed using the area under the receiver operating characteristic curve (AUC). Decision curve analysis was performed to demonstrate the clinical usefulness of the nomogram. Internal cross validation was performed to assess the validity of the predictive model. Results: In the multivariate analysis, five significant independent risk factors were identified: increased serum CA19‐9 level, low prognostic nutritional index (PNI), cyst size, enhancing mural nodule, and main pancreatic duct diameter. The nomogram based on the parameters mentioned above had outstanding performance in distinguishing malignancy, with an AUC of 0.907 (95% confidence interval: 0.859–0.956, p < 0.05), which remained 0.875 after internal cross‐validation, and showed good clinical usefulness. Conclusion: A novel nomogram for predicting malignant IPMN first introducing PNI was developed, which may aid in improving IPMN management. Nevertheless, external validation is required to confirm its efficacy. With the hope of improving the management of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, we developed a new malignancy‐predicted nomogram for IPMN, based on five verified independent predictors of malignant IPMN in our study. We employed Prognostic nutrition index (PNI) to constructed the nomogram for the first time and stratified the diameter of main pancreatic duct and the size of Mural Nodules which were helpful to achieve a more precise risk for malignancy. The nomogram shows excellent capability in predicting malignant IPMN and has a promising application potential. [ABSTRACT FROM AUTHOR]

Background: We have limited information about neuroendocrine carcinoma (NEC) of the gallbladder. The purpose of this paper is to compare clinical and pathological features between different age groups and prognostic factors for gallbladder NEC and how it differs from adenocarcinoma (ADC) of the gallbladder. Patients and methods: This study included 28 gallbladder NEC patients and 137 ADC patients whose clinical characteristics and pathological findings were retrospectively collected. Propensity score matching and Cox regression analysis were used for the analysis of prognostic factors. Results: We divided NEC patients into two groups based on the age more than or less than 60 years. Most of the NEC patients less than 60 years old complained of abdominal pain or discomfort (p = 0.038), and more younger patients accepted adjuvant therapy (p = 0.020) than older patients did. CD56 was positive in all patients more than 60 years old, which is significantly higher than that of younger patients (p = 0.039). The mean age was similar between NEC and ADC patients. After eliminating confounding factors between NEC and ADC patients, the overall survival rates were still lower in NEC patients. Univariate analysis extracted six possible risk factors. Multivariate analysis indicated that surgery type, tumor size, and existence of gallstones were independent prognostic factors. Conclusion: The overall survival of gallbladder NEC is not associated with age. In this study, surgical method and tumor size were found to be independent risk factors for NECs. In addition, NEC patients have a worse prognosis than ADC patients with similar clinical and pathological features. [ABSTRACT FROM AUTHOR]

Amylose content (AC), which is regulated by the Waxy (Wx) gene, is a major indicator of eating and cooking quality (ECQ) in rice (Oryza sativa). Thus far, only a limited number of mutations in the N‐terminal domain of Wx were found to have a major impact on the AC of rice grains and no mutations with such effects were reported for other regions of the Wx protein. Here, nucleotide substitutions in the middle region of Wx were generated by adenine and cytosine base editors. The nucleotide substitutions led to changes in 15 amino acid residues of Wx, and a series of novel Wx alleles with ACs of 0.3%–29.43% (wild type with AC of 19.87%) were obtained. Importantly, the waxyabe2 allele showed a "soft rice" AC, improved ECQ, favorable appearance, and no undesirable agronomic traits. The transgenes were removed from the waxyabe2 progeny, generating a promising breeding material for improving rice grain quality. [ABSTRACT FROM AUTHOR]

This study seeks to understand the emotional connection of teachers' academically productive talk (APT) with student learning from the students' perspective. Using a sample of 2,225 students (N7th grade = 1,146 and N8th grade = 1,079) from 16 middle schools in a city of China, we investigate the relationship between students' perceptions of their teachers' APT, student emotions (enjoyment and anxiety) and their discursive engagement with others in the mathematics classroom. Results from structural equation modelling and mediation analysis show that after controlling for gender, family resources and mathematics achievement, student‐perceived teacher APT was positively associated with their discursive engagement with classmates. Furthermore, student enjoyment and anxiety in class mediated the relationship between student‐perceived teacher APT and student discursive engagement with classmates. Multi‐group analysis revealed that the model was invariant across genders and grades, indicating that the associations were applicable to male and female students as well as to seventh and eighth graders. These findings shed light on the emotional relationship of teacher APT with the discursive engagement of their students. Although prior research observes a positive relationship between teacher productive classroom talk and student discursive engagement primarily through classroom observations and teacher reflections, this study provides evidence from the students' perspective and highlights the mediating role of student emotions in the relationship. [ABSTRACT FROM AUTHOR]

Nitrated bacterial cellulose (NBC) has been used to displace nitrocellulose (NC) because of its superior physicochemical properties, such as mechanical strength and purity, compared with NC. To meet the high energy and high strength requirements of propellants, TEGDN/NBC composites were prepared following the designs of triethylene glycol dinitrate (TEGDN) propellant. The basic properties such as structure, morphology and thermal properties were characterized by nuclear magnetic resonance spectrometer (NMR), fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), field emission scanning electron microscope (FESEM) and simultaneous thermal analysis (TG‐DSC). The rheological properties were measured and the effects of the solvents, solution concentrations and TEGDN Contents on rheological properties of TEGDN/NBC solutions were studied in detail. The results showed TEGDN/NBC composites had good flowability and low viscosity in DMF solvent. As solution concentrations increased, the viscosities of the TEGDN/NBC solutions greatly increased. As the TEGDN content increased, the viscosities, storage modulus and loss modulus firstly increased and then decreased, reached their maximum values when the TEGDN content was 15 wt %. The addition of TEGDN into NBC improved the thermal stability of NBC and the elasticity of the NBC solutions and was beneficial for its processing. [ABSTRACT FROM AUTHOR]

Drawing from multiple bodies of literature, the authors investigate the relationship between consumption-based carbon emissions and domestic income inequality for 67 nations from 1991 to 2008. Results of two-way fixed-effects longitudinal models indicate that the relationship between national-level emissions and inequality changes through time and varies for nations in different macroeconomic contexts. For high-income nations, the relationship shifts from negative to positive, suggesting that in recent years, income inequality in such nations increases carbon emissions. For middle-income nations, the association is negative, and becomes increasingly negative in the later years of the study. For low-income nations, the relationship between carbon emissions and domestic income inequality is null for the entire 1991 to 2008 period. These diverse results hold, net of the effects of other well-established human drivers of emissions, including population size, level of economic development, and urbanization. The authors conclude by emphasizing the need for future research on greenhouse gas emissions and domestic inequality, and the central role that sociology should play in this emerging area of inquiry. [ABSTRACT FROM AUTHOR]

In this article, we review the theory of ecologically unequal exchange and its relevance for global environmental injustice. According to this theory, global political–economic factors, especially the structure of international trade, shape the unequal distribution of environmental harms and human development; wealthier and more powerful Global North nations have disproportionate access to both natural resources and sink capacity for waste in Global South nations. We discuss how the theory has roots in multiple perspectives on development, world‐systems analysis, environmental sociology, and ecological economics. We detail research that tests hypotheses derived from ecological unequal exchange theory on several environmental harms, including deforestation, greenhouse gas emissions, biodiversity loss, and water pollution as well as related human well‐being outcomes. We also discuss research on social forces that counter the harmful impacts of ecologically unequal exchange, including institutions, organizations, and environmental justice movements. We suggest that ecologically unequal exchange theory provides an important global political–economic approach for research in environmental sociology and other environmental social sciences as well as for sustainability studies more broadly. [ABSTRACT FROM AUTHOR]