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In the context of climate change, agricultural cultivation, as one of the most vulnerable sectors, is under threat. Extreme weather and climate conditions have caused a series of problems, such as yield loss, more serious pests and diseases, and declining biodiversity. Conservation tillage is considered a potential method to improve climate resilience, yet the intrinsic mechanism of how conservation tillage functions to improve the climate resilience of agriculture is uncertain. Here, we performed document analysis to explore how conservation tillage stabilizes and increases crop yield and reduces greenhouse gases. We reviewed the definition of resilience and proposed the practice of conservation tillage. Our research found that conservation tillage has the potential of improving soil health and reducing greenhouse gases to enhance climate resilience. Although there is some evidence demonstrating that conservation tillage has a negative impact on crop yield and greenhouse gases, we still advocate the adoption of conservation tillage according to local conditions. We suggest that choosing proper practices, such as crop rotation, the use of cover crops, and holistic grazing, when used along with conservation tillage, can maximize the benefits of conservation tillage and alleviate the possible negative effects of this practice. [ABSTRACT FROM AUTHOR]

Wind speed and wind direction are not only important meteorological factors in environmental dynamic monitoring but also crucial parameters for harvesting considerable renewable wind energy. Although the multi-uniform unit arrangement of triboelectric nanogenerator (TENG) is a strategy for extending the responsive wind speed and direction, interunit crosstalk, low wind direction resolution, narrow working wind speed range, and unclear complex interaction between wake and wind capture component hinder further applications of wind-driven TENG. Here, a self-tuning triboelectric nanogenerator (S-TENG) is developed to effectively harvest broadband omnidirectional wind energy and simultaneously meet the high-resolution detection of wind vector. The gas-solid interaction model of this device is proposed as a two-step process. Meanwhile, owning to the self-tuning ability, the device greatly expands its working range from 2.4 to 6.4 m/s to 1.2–13.8 m/s, giving an excellent output power of 47.43 W/m3. Additionally, a real-time wind vector sensing system based on LabVIEW software exhibits wind direction resolution of up to 5° with only three channels. The recognition accuracy of wind direction relying on deep learning model reaches 98.98%. This work provides a guidance for designing effective high entropy wind energy harvesters and a deep understanding of gas-solid interaction processes. A self-tuning triboelectric nanogenerator (S-TENG) is proposed and optimized by the two-step gas-solid interaction model. The S-TENG efficiently converts omnidirectional broadband wind energy (1.2–13.8 m/s) into stable electric energy while also serving as wind vector sensing system. The device achieves power density of 47.43 W/m3, wind direction resolution of 5°, and recognition accuracy of 98.98% based on deep learning. [Display omitted] • The self-tuning strategy immensely expends wind speed and direction response ranges. • A two-step model employed hydromechanics details the dynamic gas-solid interaction. • Wind vector sensor achieves 98.98% recognition accuracy based on deep learning. [ABSTRACT FROM AUTHOR]

Background: Not all breast cancer (BC) patients who receive neoadjuvant chemotherapy achieve a pathologic complete response (pCR), but the reasons for this are unknown. Previous studies have shown that exosomes produced in the tumor microenvironment in response to chemotherapy promote a chemotherapy-resistant phenotype in tumors. However, the role of BC chemotherapy-elicited exosomes in regulating chemoresistance is poorly understood. Methods: Using commercial kits, serum exosomes were extracted from patients before neoadjuvant chemotherapy, after one cycle of chemotherapy and after four cycles of chemotherapy consisting of doxorubicin (DOX) and paclitaxel (PTX). Their miRNAs were sequenced, and the correlation between the sequencing results and chemotherapy effects was further verified by RT-qPCR using patient serum exosomes. Cell Counting Kit-8 (CCK-8) was used to detect chemosensitivity. Stemness was assessed by CD44+/CD24- population analysis and mammosphere formation assays. Chromatin immunoprecipitation (ChIP) experiments were performed to verify the binding of signal transducer and activator of transcription 3 (STAT3) to the promoter of miRNAs. Results: Here, we provide clinical evidence that chemotherapy-elicited exosomal miR-378a-3p and miR-378d are closely related to the chemotherapy response and that exosomes produced by BC cells after stimulation with DOX or PTX deliver miR-378a-3p and miR-378d to neighboring cells to activate WNT and NOTCH stemness pathways and induce drug resistance by targeting Dickkopf 3 (DKK3) and NUMB. In addition, STAT3, which is enhanced by zeste homolog 2 (EZH2), bound to the promoter regions of miR-378a-3p and miR-378d, thereby increasing their expression in exosomes. More importantly, chemotherapeutic agents combined with the EZH2 inhibitor tazemetostat reversed chemotherapy-elicited exosome-induced drug resistance in a nude mouse tumor xenograft model. Conclusion: This study revealed a novel mechanism of acquired chemoresistance whereby chemotherapy activates the EZH2/STAT3 axis in BC cells, which then secrete chemotherapy-elicited exosomes enriched in miR-378a-3p and miR-378d. These exosomes are absorbed by chemotherapy-surviving BC cells, leading to activation of the WNT and NOTCH stem cell pathways via the targeting of DKK3 and NUMB and subsequently resulting in drug resistance. Therefore, blocking this adaptive mechanism during chemotherapy may reduce the development of chemotherapy resistance and maximize the therapeutic effect. [ABSTRACT FROM AUTHOR]

The thermomechanical constitutive models are critical for shape memory polymers (SMPs) in analyzing their shape memory behaviors under different conditions. Recently, the phase evolution modeling approach proposed by Liu et al. (2006) has been extended and widely used due to its simplicity and generality. However, the lack of physical explanation has become its major limitation. In this study, a phase evolution law was proposed from the physics perspective. The shape memory polymer was then treated as a frozen-phase matrix with active-phase inclusions embedded in it and the Mori-Tanaka approach was used to predict the effective mechanical properties. The theoretical predictions were compared with available experimental results and reasonable agreement was found. The influence of the intrinsic material structures and the thermomechanical conditions on the shape memory behavior were evaluated by parametric studies. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, the stress recovery behavior of shape memory polyurethane (SMPU) fiber was investigated. The as-spun SMPU fibers were subjected to various programing-recovery conditions. It was observed that recovering at 100 °C generated higher recovery stress than recovering at 150 °C. It was also found that, while hot-drawn programed fiber has higher recovery stress than cold-drawn programed fiber if recovered at 100 °C, cold-drawn programed fiber has higher stabilized recovery stress than hot-drawn programed counterpart when recovered at 150 °C. A morphological model was proposed based on the results from differential scanning calorimetry, Fourier transform infrared spectrometry, and X-ray diffraction to understand the physics behind the different stress recovery behaviors. It is found that SMPU experiences different phase transitions and phase separations under different programing and stress recovery conditions. It is concluded that the two sequential phase separations taking place at 100 and 150 °C are primarily responsible for the differences in the stress recovery behavior. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1429-1440 [ABSTRACT FROM AUTHOR]

Nowadays, the development of direct current triboelectric nanogenerators (DC‐TENGs) is oriented toward practical applications such as real‐time efficient harvesting and supplying energy. This demands DC‐TENGs with a low loss factor, high energy utilization efficiency, device portability, and output stability. Herein, a constant‐voltage DC‐TENG (C‐DC‐TENG) with robust output performance, using the ternary dielectric triboelectrification effect is demonstrated, which gives a crest factor of 1.0082. The key to improving the output charge density is the number of subdivision units, a result of theoretical simulations and experiments of C‐DC‐TENG. The optimized C‐DC‐TENG achieves not only an output charge density of 3.902 mC m−2 per round but also an average power density of 8.77 W m−2 (3.508 W m−2 Hz−1), which both set a new record for the rotary DC‐TENG. Moreover, introducing soft polyester fur enables C‐DC‐TENG to maintain 100% output without wear after 800 000 cycles. This C‐DC‐TENG is faultlessly competent for powering 2784 LEDs in series and 25 parallel‐connected hygrothermographs continuously. This work provides a promising technique for large‐scale clean energy harvesting, accelerating the progress toward practical applications of DC‐TENG. [ABSTRACT FROM AUTHOR]

• A phenomenological model for three types of two-way shape memory effect. • A model considering both entropic elasticity and strain induced crystallization mechanisms. • Model validated by experiments. • Model parameters ranked through model sensitivity analysis. Recently, two-way shape memory effect (2W-SME) has been demonstrated in several types of shape memory polymers (SMPs). Unlike classical one-way shape memory effect (1W-SME), these polymers can switch back and forth repeatedly between two different shapes without subsequent programming procedure. The reversible actuation can be realized either under a constant external tensile load, which is referred to as quasi 2W-SME, or under zero load, which is referred to as true 2W-SME. Most recently, actuation under an external compressive load, which is referred to as advanced 2W-SME, has also been discovered. Test results have shown that semicrystalline 2W-SMPs exhibit 2W-SME in two distinct regions due to two different mechanisms: one is due to entropic elasticity above the crystallization temperature, and the other is due to melt/crystallization transition below the crystallization temperature. While several constitutive models have been developed over the years for semicrystalline 2W-SMPs, there is currently a lack of effort towards modeling the true and advanced 2W-SME within the two-mechanism framework. In this study, we developed a thermomechanical constitutive model which captured both the entropic elasticity and melt/crystallization events. The modeling results and test results show reasonable agreement. It is found that the model captured the three types of 2W-SMEs: quasi 2W-SME, true 2W-SME, and advanced 2W-SME. It is also found that proper tensile programming before the first thermomechanical cycle can make a semicrystalline SMP exhibit all the three types of 2W-SMEs. This study may serve as a design tool to enhance applications of semicrystalline 2W-SMPs in engineering structures and devices. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Fire warning and monitoring are very important for public safety and environmental protection. However, most of the proposed wind energy conversion devices based on triboelectric nanogenerator (TENG) only work for unidirectional and high‐speed wind and face the challenge of fatigue damage and even failure caused by cyclic stress. Moreover, TENG guided by the theory of fluid dynamics needs further exploration. Herein, a flow‐induced vibration effect based TENG (F‐TENG) for continuously capturing and monitoring multidirectional breeze (1.8–4.3 m s−1) is developed to build a self‐powered intelligent fire detection system (SIFDS). A dynamic model is proposed to study the intrinsic interaction between the electrical properties of F‐TENG and wind. Since the model optimized F‐TENG is more adaptable to wind characteristics, it delivers better performance and higher durability compared with previous studies. Relying on the dynamic model and combining the relationship between F‐TENG's electrical output and wind characteristics, a self‐powered visual wind sensing system is obtained. F‐TENG successfully drives some electronic devices to monitor environmental information, which is expected to provide data for SIFDS to reduce fire hazards. This study can provide an in‐depth understanding of the electromechanical conversion mechanism and large‐scale capture and utilization of breeze energy. [ABSTRACT FROM AUTHOR]

The free‐standing triboelectric nanogenerator (F‐S TENG) is demonstrated to be an efficient energy conversion device. However, limited by the inherent features of high‐voltage, low alternating current and high output impedance, TENGs suffer from inefficient energy utilization and difficulties in practical applications. Therefore, the efficient harvest of mechanical energy and optimization of output are currently critical issues for TENGs. Here, a strategy is proposed for optimizing the inherent features by coupling F‐S TENG to a capacitor auto‐conversion circuit (CAC). For the first time, a specific idea is proposed explicitly to reduce the output impedance by the management circuit. Eventually, a high current density of 32 A m−2 and a charge density of 1.75 mC m−2 are achieved, which is 8.78 times higher than previous works. The power density and energy density reach to 124 W m−2 and 252 mJ m−2 under 470 and 150 Ω respectively. Then, 5000 LEDs and two lamps rated at 220 V and 50 W are manually illuminated. The resulting pulse output is utilized as a trigger source for the thyristor, enabling DC contactless switching. This work provides a novel approach to realize high‐performance DC output of TENGs and effectively reduce external load impedance. [ABSTRACT FROM AUTHOR]

Purpose: In this study, we aimed to explore the potential significance of AR expression in HER2-positive breast cancer patients who underwent neoadjuvant targeted therapy. Specifically, we investigated the correlation between AR expression levels and pathological complete response (pCR) rates. Our objective was to determine whether there were significant differences in pCR rates among HER2-positive breast cancer patients with different levels of AR expression. Methods: We conducted a retrospective analysis of 258 HER-2 positive breast cancer patients who underwent neoadjuvant dual-blocked standard therapy (following the NCCN Guideline 2021) at three breast cancer centers in southwest China. We analyzed the clinicopathological features and pCR rates of these patients. The cut-off value for AR expression level was calculated as the median value of 70%. We used the chi-square test to investigate the correlation between AR expression level and pCR rate, as well as other clinicopathological features. Results: Out of the 258 patients analyzed, 154 (59.69%) achieved pCR. Based on the cut-off value of 70%, AR expression level was classified as low (AR ≤ 70%) or high (AR > 70%) expression. Our analysis revealed a significant correlation between AR expression level and pCR rate in HER2-positive breast cancer patients (P = 0.031). We also found a significant association between pCR rate and clinical stage (P = 0.033) and chemotherapy regimen (P = 0.034). Furthermore, subgroup analyses showed that the pCR rate was higher in patients with high AR expression levels compared to those with low AR expression levels. Additionally, we observed that patients with an ER/AR ratio of less than 1 had a higher pCR rate than those with an ER/AR ratio greater than 1 (P = 0.038). Conclusion: Our study findings suggest that HER2-positive breast cancer patients with high AR expression levels may achieve higher pCR rates when treated with neoadjuvant dual-blocked therapy. Overall, our results support the idea that AR expression levels have a significant correlation with pCR rates in HER2-positive breast cancer patients receiving this particular form of treatment. [ABSTRACT FROM AUTHOR]

Glutamate dehydrogenase (GDH) plays an important role in the ammonium assimilation and nitrogen metabolism by catalyzing the reversible oxidative deamination of L-glutamate to α-ketoglutarate. In the present study, the potential functions of GDH in response to heat stress were explored in the scleractinian coral Pocillopora damicornis (designated as PdGDH). The cDNA of PdGDH contained an open reading frame of 1 611 bp encoding a polypeptide of 536 amino acids, which exhibited the highest sequence identity to GDH of Stylophora pistillata (96% identity), and the deduced PdGDH protein was predicted to contain one GdhA domain (from Val95 to Tyr525). The recombinant protein of PdGDH (rPdGDH) was expressed in Escherichia coli BL21 (DE3)-Transetta, and its catalytic activity was measured under different temperatures, pH conditions and epigallocatechin-3-gallate (EGCG, a GDH inhibitor) concentrations. The purified rPdGDH only used reduced coenzyme nicotinamide adenine dinucleotide (NADH) as coenzyme, and its highest activity was observed at 35 °C and pH 7.5, respectively. The rPdGDH activity was negatively correlated with the concentration of EGCG, and was inhibited by more than half (65%, P<0.05) at 10−4 mol/L EGCG. No significant alteration of PdGDH mRNA expression was detected at 12 h after exposure to heat and ammonium (P>0.05). Furthermore, the activities of NADH-GDH in the scleractinian coral P. damicornis increased significantly at 12 h after the heat and ammonium stress, and the NADH-GDH activity in the heat stress group (32.66 U/mg, P<0.05) was significantly higher than that in the heat and ammonium stress group (11.26 U/mg). These results collectively suggested that PdGDH, as a homologue of glutamate dehydrogenase in the scleractinian coral P. damicornis, could respond to heat stress at the protein level, which would have ability to further promote ammonium assimilation to increase the heat acclimatization of the coral-Symbiodiniaceae symbiotic association. [ABSTRACT FROM AUTHOR]

[Display omitted] • Balsa-derived magnetic Fe 3 C/N@BsB was prepared with curcumin as a mediator. • Fe 3 C/N@BsB had dual active sites to activate PMS for catalytic degradation of PFOA. • Degradation and defluorination efficiencies were 82.9% and 71.4% for PFOA at 4 h. • SO 4 − dominated in the system, with maximum accumulation concentration of 29.6 μM. • In-situ magnetized Fe 3 C/N@BsB with cm-size was convenient for recycling for reuse. Perfluorooctanoic acid (PFOA) is one of the most commonly detected perfluorinated compounds, and now poses a significant threat to animal, plant and human health as an emerging pollutant. Using balsa wood as a natural template and potassium ferrocyanide as a precursor, curcumin-mediated Fe 3 C/N-embedded 3D magnetic biochar (Fe 3 C/N@BsB) was obtained in this study via a facile in-situ pyrolysis method. Featured with dual metallic and non-metallic active centers, Fe 3 C/N@BsB was then utilized for activating peroxymonosulfate (PMS) to degrade PFOA in water. The experimental data indicated that a degradation efficiency of 82.9% and defluorination efficiency of 71.4% were achieved for PFOA at room temperature and pH 3.0. Coexisting 50 mM Cl− in water had no significant impact, while HCO 3 − and HA showed inhibitory effects on PFOA degradation. By the identification and quantification of free radicals, SO 4 − was predominant in the Fe 3 C/N@BsB + PMS system with its maximum accumulation concentration of 29.6 μM. Under the attack of active species, PFOA degradation occurred gradually to produce short-chain by-products for subsequent mineralization. Finally, the recyclability of Fe 3 C/N@BsB and its catalytic degradability in tap water and Yellow River water were also evaluated. This study not only demonstrates the enormous potential of Fe 3 C/N@BsB + PMS system for the removal of emerging PFOA in water, but also provides good theoretical support for the resource utilization of balsa wood. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is characterized by high vascularity, but anti-angiogenic therapies show poor efficacy. Centromere protein U (CENPU), a centromere component essential for mitosis, is associated with tumorigenesis in multiple cancers; however, little is known of its role in breast cancer. Here, we investigate its expression and function of promoting angiogenesis in TNBC. Immunohistochemical staining revealed high CENPU expression in TNBC tissue and high CENPU levels correlated significantly with poor distant metastasis-free and overall survival. Knockdown of CENPU in TNBC cells inhibited vascular endothelial growth factor A (VEGFA) production and significantly reduced tube formation and migration of human umbilical vein endothelial cells in vitro. In a mouse xenograft model, CENPU knockdown reduced TNBC tumor growth concomitant with a reduction in CD31 + microvessel density. Mechanistic studies revealed that CENPU promoted angiogenesis by inhibiting the ubiquitination and proteasomal degradation of cyclooxygenase-2 (COX-2), leading to increased activation of the COX-2-p-ERK-HIF-1α-VEGFA signaling pathway. Taken together, our results demonstrate a critical role for CENPU in COX-2-mediated signaling for angiogenesis, and identify a role of CENPU in regulating angiogenesis in TNBC. [ABSTRACT FROM AUTHOR]

Misregulation of BCL-2 family of proteins renders a survival signal to withstand cytotoxic anticancer drugs and is often found in drug resistant cells. The drug resistance phenotype is also associated with an enhancement of cancer stem cell-like (CSC) characteristics. Thus, inhibition of anti-apoptotic BCL-2 family proteins has been proposed as a possible antineoplastic strategy, and BCL-2 inhibitors are currently being clinically trailed in patients with leukemia, lymphoma or non-small cell lung cancer. However, the effects of BCL-2 inhibitors on drug resistant breast cancer have not yet been elucidated. In the present study, the effect of sabutoclax, a pan-active BCL-2 protein family antagonist, on two chemoresistant breast cancer cell lines was assessed. We found that sabutoclax showed a significant cytotoxic activity on chemoresistant breast cancer cells both in vitro and in vivo. When chemotherapeutic agents were combined with sabutoclax, strong synergistic antiproliferative effects were observed. Sabutoclax induced the blockage of BCL-2, MCL-1, BCL-xL and BFL-1, which in turn led to caspase-3/7 and caspase-9 activation and modulation of Bax, Bim, PUMA and survivin expression. Furthermore, sabutoclax effectively eliminated the CSC subpopulation and reduced sphere formation of drug-resistant cells through down-regulation of the IL-6/STAT3 signaling pathway. A similar effect was observed in a small panel of nine breast tumors ex vivo. Our findings indicate that sabutoclax partially overcomes the drug resistance phenotype of breast cancer cells by reactivation of apoptosis, mediated by the inhibition of several anti-apoptotic BCL-2 family proteins, and eliminates CSCs by abolition of the IL-6/STAT3 pathway. This offers a strong rationale to explore the therapeutic strategy of using sabutoclax alone or in combination for chemotherapy-nonresponsive breast cancer patients. [ABSTRACT FROM AUTHOR]