Ferroptosis is an iron-dependent form of regulated cell death that is triggered by the toxic build-up of lipid peroxides on cellular membranes. In recent years, ferroptosis has garnered enormous ...interest in cancer research communities, partly because it is a unique cell death modality that is mechanistically and morphologically different from other forms of cell death, such as apoptosis, and therefore holds great potential for cancer therapy. In this Review, we summarize the current understanding of ferroptosis-inducing and ferroptosis defence mechanisms, dissect the roles and mechanisms of ferroptosis in tumour suppression and tumour immunity, conceptualize the diverse vulnerabilities of cancer cells to ferroptosis, and explore therapeutic strategies for targeting ferroptosis in cancer.
The cystine/glutamate antiporter SLC7A11 (also commonly known as xCT) functions to import cystine for glutat hione biosynthesis and antioxidant defense and is overexpressed in multiple human cancers. ...Recent studies revealed that SLC7A11 overexpression promotes tumor growth partly through suppressing ferroptosis, a form of regulated cell death induced by excessive lipid peroxidation. However, cancer cells with high expression of SLC7A11 (SLC7A11 high) also have to endure the significant cost associated with SLC7A11-mediated metabolic reprogramming, leading to glucoseand glutamine-dependency in SLC7A11 high cancer cells, which presents potential metabolic vulnerabilities for therapeutic targeting in SLC7A11 high cancer. In this review, we summarize diverse regulatory mechanisms of SLC7A11 in cancer, discuss ferroptosis-dependent and-independent functions of SLC7A11 in promoting tumor development, explore the mechanistic basis of SLC7A11-induced nutrient dependency in cancer cells, and conceptualize therapeutic strategies to target SLC7A11 in cancer treatment. This review will provide the foundation for further understanding SLC7A11 in ferroptosis, nutrient dependency, and tumor biology and for developing novel effective cancer therapies.
Synthesize the evidence relating to the interaction of resilience, stress, and well-being in undergraduate nursing students across countries.
Systematic review
Peer reviewed studies published from ...2008 to December 2018 were searched in CINAHL, Web of Science, Medline (OVID), PsycINFo and four biomedical databases originating from China (China National Knowledge Infrastructure, WanFang Data, VIP and CMB).
Adhering to the preferred reporting items for Systematic Reviews and Meta-analyses guidelines, eight databases were searched. Twelve studies, which met the inclusion criteria, were extracted, and subject to quality appraisal by two researchers.
In total, 12 papers were included. Outcome analysis revealed the level of resilience as moderate; stress levels were high and the incidence of negative psychological health accounts for a proportion of nursing students. The interaction between resilience and stress and well-being was high. Resilience and low stress were found to better predict well-being. All the studies cited recommendations to inform educational policy and practice in relation to resilience, well-being, and stress among undergraduate nursing students.
This was the first systematic review to synthesize the evidence relating to the interaction of resilience, stress, and well-being in undergraduate nursing students across cultural settings. Evidence confirms the importance of resilience in nursing students influencing stress and psychosocial morbidity. Nursing educational strategies that foster and enhance resilience is recommended.
Anomaly detection in a hyperspectral image (HSI) has been actively researched in the field of remote sensing due to its significant application requirements. Traditional methods were based on the ...spatial models for the background to detect the anomaly targets. However, in detecting the spectral anomaly targets, they led to two problems: 1) the spatial characteristics of spectral anomaly targets are not obvious, which causes many false alarms in detection and 2) spectral anomaly usually occurs in the local band of targets, while the rest of the spectrum is similar to the ones of surrounding backgrounds, which leads to missed detection. This article proposes a novel hyperspectral anomaly detection method for spectral anomaly targets based on spatial and spectral constraints (SASCs). This model finds suspected anomaly target part as spatial anomaly results through SASCs. Then, the feedback process determines the spectral anomaly through the spectral difference between the tested pixel and the surrounding background. It is fed back to the spatial anomaly results to obtain final detection results. Furthermore, in order to enlarge the spectral difference between anomaly and background while suppressing the background, the optimal order of fractional Fourier transform (FrFT) is determined by combining spatial anomaly results with the uncertainty principle, which is used in FrFT of HSI. Experimental results show that the proposed method suppresses the background and reduces the false alarm rate. The feedback mechanism effectively reduces the missing detection rate, achieving a promising detection accuracy.
Anomaly detection is a key problem in hyperspectral image (HSI) analysis with important remote sensing applications. Traditional methods for hyperspectral anomaly detection are mostly based on the ...distinctive statistical features of the HSIs. However, the anomaly-detection performance of these methods has been negatively impacted by two major limitations: 1) failure to consider the spatial pixel correlation and the ground-object correlation and 2) the existence of the mixing pixels caused by both lower spatial resolution and higher spectral resolution, which leads to higher false-alarm rates. In this article, these two problems are largely solved through a novel hyperspectral anomaly-detection method based on image super-resolution (SR) and spatial correlation. The proposed method encompasses two innovative ideas. First, based on the spectral variability in the anomaly targets, an extended linear mixing model can be obtained with more accurate ground-object information. Then, image SR is used to improve the spatial resolution of the HSIs by injecting the ground-object information from the mixing model. This alleviates the effect of mixed pixels on anomaly detection. Second, spatial correlation is exploited jointly with the global Reed-Xiaoli (GRX) method and the ground-object correlation detection for anomaly detection. Experimental results show that the proposed method not only effectively improves the hyperspectral spatial resolution and reduces the false-alarm rate but also increases the detectability with the spatial correlation information. Furthermore, the results for the real HSIs demonstrate that the proposed method achieves higher rates of anomaly detection with lower false-alarm rates.
•The geochemical features of meta-basalts indicate an arc origin.•The protolith and metamorphic ages were of ∼2.2 and ∼1.9Ga.•The Jiao-Liao-Ji Belt may represent an arc-continent collisional belt.
...Geochronology, geochemical and isotopic studies were carried out on the Paleoproterozoic meta-basalts and related rocks from the Jiao-Liao-Ji Belt, North China Craton, to understand the mantle source characteristics and the geodynamic setting. U-Pb isotopic dating using the LA-ICPMS method on zircons from the metamorphosed volcanic rocks reveals that they formed at ca. 2204–2158Ma and were metamorphosed at ca. 1895–1919Ma, respectively. The meta-basalts are of calc-alkali affinity and have arc-like geochemical compositions. They are enriched in LREEs ((La/Yb)N=3.5–5.1) and LILEs (Sr, Ba, Rb), depleted in HFSEs (Nb, Ta, Zr, Hf, Ti), and show variable high ɛNd(t) values (+2.4 to +4.5). The basaltic rocks experienced significant fractional crystallization and minor crustal contamination during magma evolution. Modeling suggests that the parent magma of the meta-basalts was derived from 20% partial melting of spinel-garnet lherzolites that were previously metasomatized by subduction zone fluids/melts in the Late Archean. Petrological, geochronological and geochemical data suggest that the Paleoproterozoic volcanic rocks formed in an active continental margin setting and were subsequently deformed and metamorphosed to amphibolite facies due to the arc-continental collision at ca. 1.9Ga, rather than in a continental rifting setting as previously thought by most workers.
Hybrid manganese halide has attracted much attention in the field of environment friendly ferroelectric and photo‐responsive multifunctional materials. Here, the highly efficient photoluminescent ...inorganic framework MnBr42− is utilized to conceive and synthesize a series of hybrid manganese bromide compounds RQ2MnBr4 by introducing precisely designed quasi‐spherical cations RQ+ (R = H, Me, Et, FEt, Q = quinuclidine). The accurate and effective modification of cations not only achieves the satisfactory ferroelectricity, but also enhances the photoluminescence quantum yield from 38.7% to 83.65%. Moreover, FEtQ2MnBr4 shows a highly efficient X‐ray scintillator performance, including a large range of linear response to X‐ray dose rate from 0.3 to 414.2 μGyair s−1, a high light yield of 34 438 photons per MeV, and a low detection limit of 258 nGyair s−1. This work provides an efficient strategy for the preparation of hybrid manganese halide ferroelectrics with highly efficient light‐emission and X‐ray detection.
By coupling the design for high Curie temperature ferroelectrics and the modulation of photo‐responsive properties through precise modification of spherical cations, an A2MnBr4‐type hybrid ferroelectric with a high photoluminescence quantum yield of 83.65% is obtained. Moreover, the eco‐friendly crystal is promising for high performance X‐ray detectors compared with commercially available scintillators such as bismuth germanium oxide and lutetium yttrium oxyorthosilicate.
Tight sandstone reservoir has the characteristics of low porosity, low permeability and strong reservoir heterogeneity, which leads to a rapid decline in single well production after hydraulic ...fracturing. Adding nano emulsion to fracturing fluid can not only realize the dual function of fracturing and imbibition oil displacement, but also effectively prolong the stable production time of oil wells. In order to improve the understanding of the interaction between nano emulsion and reservoir, this paper based on the basic physical property test and analysis of nano emulsion, macroscopic and microscopic spontaneous imbibition oil displacement experiments, the mechanism of imbibition displacement of nano emulsion in tight sandstone reservoirs and the influence of related factors is clarified. The results show that: ①The particle size of the three types of nano emulsions ranges from 11 to 16 nm, and they can enter the nanopore throats deep in the reservoir, and can achieve good injectivity in tight reservoirs. The anionic AES nano emulsion is superior to cationic ADT and nonionic AEO-9 nano emulsion in terms of injectability, oil-water interfacial tension and wetting modification effect in tight sandstone cores, and the optimal concentration is 0.30 wt%. ②Spontaneous imbibition oil displacement experiments show that the nano emulsion concentration is not the higher the better. Since the nano emulsion adsorption on the solid surface reaches a dynamic equilibrium, the excessive nano emulsion cannot further change the wettability of the solid surface, and the lower oil-water interfacial tension has the opposite effect on the imbibition displacement. ③The migration and gathering of emulsified oil droplets in solution mainly included five processes: Saturated oil core/Nano-surfactant fluid emulsion reaction, Aqueous/Emulsified oil droplets, Emulsified oil droplet gathering phase, Demulsifying and emulsifying oil droplets, Oil phase after demulsification. The generation of remaining oil in porous media is due to the non-uniform wetting modification in different regions. This study further improves the understanding of the mechanism of spontaneous imbibition of nano emulsion in tight sandstone reservoirs.
Construction of ferroelectric and optimization of macroscopic polarization has attracted tremendous attention for next generation light weight and flexible devices, which brings fundamental vitality ...for molecular ferroelectrics. However, effective molecular tailoring toward cations makes ferroelectric synthesis and modification relatively elaborate. Here, the study proposes a facile method to realize triggering and optimization of ferroelectricity. The experimental and theoretical investigation reveals that orientation and alignment of polar cations, dominated factors in molecular ferroelectrics, can be controlled by easily processed anionic modification. In one respect, ferroelectricity is induced by strengthened intermolecular interaction. Moreover, ≈50% of microscopic polarization enhancement (from 8.07 to 11.68 µC cm−2) and doubling of equivalent polarization direction (from 4 to 8) are realized in resultant ferroelectric FEtQ2ZnBrI3 (FEQZBI, FEtQ = N‐fluoroethyl‐quinuclidine). The work offers a totally novel platform for control of ferroelectricity in organic–inorganic hybrid ferroelectrics and a deep insight of structure–property correlations.
Targeted modified anions can induce ferroelectricity and result in an enhanced ferroelectric ordering indirectly. The facile optimization strategy takes full advantage of structural flexibility of hybrid materials and provides a totally novel and expansive platform for construction of ferroelectrics and optimization of ferroelectricity in corresponding fields.
Cancer cells often upregulate nutrient transporters to fulfill their increased biosynthetic and bioenergetic needs, and to maintain redox homeostasis. One nutrient transporter frequently ...overexpressed in human cancers is the cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11; also known as xCT). SLC7A11 promotes cystine uptake and glutathione biosynthesis, resulting in protection from oxidative stress and ferroptotic cell death. Recent studies have unexpectedly revealed that SLC7A11 also plays critical roles in glutamine metabolism and regulates the glucose and glutamine dependency of cancer cells. This review discusses the roles of SLC7A11 in regulating the antioxidant response and nutrient dependency of cancer cells, explores our current understanding of SLC7A11 regulation in cancer metabolism, and highlights key open questions for future studies in this emerging research area. A deeper understanding of SLC7A11 in cancer metabolism may identify new therapeutic opportunities to target this important amino acid transporter for cancer treatment.
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