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Abstract Numerous geothermal systems are hosted by extensional rifts that transect the Himalayas and Lhasa block in the Himalayan–Tibetan orogen. However, the relationships between hydrogeological processes and geothermal fluid circulation in different tectonic units remain unclear. Here, we report an integrated dataset of chemical and isotopic compositions (including major and trace elements, δD, δ18O, and 87Sr/86Sr) of thermal spring water from the Tingri-Tangra Yumco rift to assess their origins and circulation processes. δ18O (− 21.3 to − 17.0‰) and δD (− 166 to − 135‰) values of thermal springs indicate dominant recharge of meteoric waters from areas with elevation of > 6000 m and minor addition of magmatic fluids. Meteoric water could infiltrate to depths of about 1700–2900 m along the faults, whereby it is influenced by geothermal gradient and/or conductive heat transfer of magmatic fluids. The thermal spring waters are mainly Na-HCO3 type and are controlled by dissolution of silicate and carbonate minerals and mixing with deep fluids. The results of chemical and multicomponent geothermometers indicate reservoir temperatures of 115 − 195 ℃, corresponding to a convection heat flux of 3.96 × 105 J/s to 1.78 × 107 J/s from geothermal systems, which are comparable to that of the low-enthalpy geothermal systems in southern Italy. Geochemical modeling is conducted to assess the water–mineral equilibria in the reservoir. Trace elements and 87Sr/86Sr data suggest spatially variable controlling factors for the rift-related geothermal systems: (1) interaction with granitoid and carbonate in the Himalayas; (2) cold groundwater mixing with that leaching from granite and volcanic rocks in the Lhasa block; (3) the input of vapors from magmatic degassing. The geochemistry of thermal springs associated with extensional rift is largely induced by the interaction between fluid and different reservoir rocks in the Himalayas and Lhasa block. Based on these findings, a genetic model is proposed for exploration and development of geothermal resources in the Tingri-Tangra Yumco rift.

Background and aim: Accurately predicting microvascular invasion (MVI) before surgery is beneficial for surgical decision-making, and some high-risk hepatocellular carcinoma (HCC) patients may benefit from postoperative adjuvant transarterial chemoembolization (PA-TACE). The purpose of this study was to develop and validate a novel nomogram for predicting MVI and assessing the survival benefits of selectively receiving PA-TACE in HCC patients. Methods: The 1372 HCC patients who underwent hepatectomy at four medical institutions were randomly divided into training and validation datasets according to a 7:3 ratio. We developed and validated a nomogram for predicting MVI using preoperative clinical data and further evaluated the survival benefits of selective PA-TACE in different risk subgroups. Results: The nomogram for predicting MVI integrated alpha-fetoprotein, tumor diameter, tumor number, and tumor margin, with an area under the curve of 0.724, which was greater than that of any single predictive factor. The calibration curve, decision curve, and clinical impact curve demonstrated that the nomogram had strong predictive performance. Risk stratification based on the nomogram revealed that patients in the low-risk group did not achieve better DFS and OS with PA-TACE (all p > 0.05), while patients in the medium-to-high risk groups could benefit from higher DFS (Medium-risk, p = 0.039; High-risk, p = 0.027) and OS (Medium-risk, p = 0.001; High-risk, p = 0.019) with PA-TACE. Conclusions: The nomogram predicting MVI demonstrated strong predictive performance, and its risk stratification aided in identifying different subgroups of HCC patients who may benefit from PA-TACE with improved survival outcomes.

Abstract The active Himalayan-Tibetan orogen, where India underthrusts into Asia, is an important geological source of carbon dioxide (CO2) emission into Earth’s atmosphere. However, the extent to which Indian underthrusting could stimulate the mobilization of deeply-sourced carbon and its subsequent emission remains unknown. Here, we use a combination of field observations coupled with in-situ CO2 flux measurements and helium and carbon isotopic data, to study the controls on CO2 origins and fluxes in a 400-kilometre-long rift transecting northern Himalaya and southern Tibet. High diffuse CO2 fluxes sustained by pure crustal fluids are confined to rift segments in the northern Himalaya, while toward southern Tibet, CO2 fluxes become lower but mantle fluid inputs are identified. Such rift-related CO2 degassing profile suggests metamorphic decarbonation and release of carbon-bearing fluids enhanced by the underthrusting Indian lower crust, agreeing well with Himalayan metamorphism and orogen-parallel lithospheric extension. Deep CO2 fluxes from extensional tectonics in northern Himalaya and southern Tibet, primarily of crustal origins, are comparable to mantle CO2 fluxes from global mid-ocean ridges. Our findings demonstrate that geophysical and geo-tectonic responses to continental underthrusting could facilitate massive crustal carbon mobilization and emission, making active collisional orogens globally important carbon sources.

Abstract Sodium ion batteries (SIBs) are considered as the ideal candidates for the next generation of electrochemical energy storage devices. The major challenges of anode lie in poor cycling stability and the sluggish kinetics attributed to the inherent large Na+ size. In this work, Bi nanosphere encapsulated in N‐doped carbon nanowires (Bi@N‐C) is assembled by facile electrospinning and carbonization. N‐doped carbon mitigates the structure stress/strain during alloying/dealloying, optimizes the ionic/electronic diffusion, and provides fast electron transfer and structural stability. Due to the excellent structure, Bi@N‐C shows excellent Na storage performance in SIBs in terms of good cycling stability and rate capacity in half cells and full cells. The fundamental mechanism of the outstanding electrochemical performance of Bi@N‐C has been demonstrated through synchrotron in‐situ XRD, atomic force microscopy, ex‐situ scanning electron microscopy (SEM) and density functional theory (DFT) calculation. Importantly, a deeper understanding of the underlying reasons of the performance improvement is elucidated, which is vital for providing the theoretical basis for application of SIBs.

Photothermal catalysis realizes the synergistic effect of solar energy and thermochemistry, which also has the potential to improve the reaction rate and optimize the selectivity. In this review, the research progress of photothermal catalytic removal of volatile organic compounds (VOCs) by nano-catalysts in recent years is systematically reviewed. First, the fundamentals of photothermal catalysis and the fabrication of catalysts are described, and the design strategy of optimizing photothermal catalysis performance is proposed. Second, the performance for VOC degradation with photothermal catalysis is evaluated and compared for the batch and continuous systems. Particularly, the catalytic mechanism of VOC oxidation is systematically introduced based on experimental and theoretical study. Finally, the future limitations and challenges have been discussed, and potential research directions and priorities are highlighted. A broad view of recent photothermal catalyst fabrication, applications, challenges, and prospects can be systemically provided by this review.

Background: Hepatocellular carcinoma (HCC) patients have a poor prognosis after radio-frequency ablation (RFA), and investigating the risk factors affecting RFA and establishing predictive models are important for improving the prognosis of HCC patients. Methods: Patients with HCC undergoing RFA in Shenzhen People’s Hospital between January 2011 and December 2021 were included in this study. Using the screened independent influences on recurrence and survival, predictive models were constructed and validated, and the predictive models were then used to classify patients into different risk categories and assess the prognosis of different categories. Results: Cox regression model indicated that cirrhosis (hazard ratio [HR] = 1.65), alpha-fetoprotein (AFP) ⩾400 ng/mL (HR = 2.03), tumor number (multiple) (HR = 2.11), tumor diameter ⩾20 mm (HR = 2.30), and platelets (PLT) ⩾ 244 (10 9 /L) (HR = 2.37) were independent influences for recurrence of patients after RFA. On the contrary, AFP ⩾400 ng/mL (HR = 2.48), tumor number (multiple) (HR = 2.52), tumor diameter ⩾20 mm (HR = 2.25), PLT ⩾244 (10 9 /L) (HR = 2.36), and hemoglobin (HGB) ⩾120 (g/L) (HR = 0.34) were regarded as independent influences for survival. The concordance index (C-index) of the nomograms for predicting disease-free survival (DFS) and overall survival (OS) was 0.727 (95% confidence interval [CI] = 0.770-0.684) and 0.770 (95% CI = 0.821-7.190), respectively. The prognostic performance of the nomograms was significantly better than other staging systems by analysis of the time-dependent C-index and decision curves. Each patient was scored using nomograms and influencing factors, and patients were categorized into low-, intermediate-, and high-risk groups based on their scores. In the Kaplan-Meier survival curve, DFS and OS were significantly better in the low-risk group than in the intermediate- and high-risk groups. Conclusions: The 2 prediction models created in this work can effectively predict the recurrence and survival rates of HCC patients following RFA.

Abstract Background The survival benefit of adjuvant transarterial chemoembolization (TACE) in patients with hepatectomy for hepatocellular carcinoma (HCC) after hepatectomy remains controversial. We aimed to investigate the survival efficacy of adjuvant TACE after hepatectomy for HCC. Methods 1491 patients with HCC who underwent hepatectomy between January 2018 and September 2021 at four medical centers in China were retrospectively analyzed, including 782 patients who received adjuvant TACE and 709 patients who did not receive adjuvant TACE. Propensity score matching (PSM) (1:1) was performed to minimize selection bias, which balanced the clinical characteristics of the two groups. Results A total of 1254 patients were enrolled after PSM, including 627 patients who received adjuvant TACE and 627 patients who did not receive adjuvant TACE. Patients who received adjuvant TACE had higher disease-free survival (DFS, 1- ,2-, and 3-year: 78%-68%-62% vs. 69%-57%-50%, p

Supported metal catalysts, particularly for precious metals, have gained increasing attention in green synthetic chemistry. They can make metal-catalyzed organic synthesis more sustainable and economical due to easy separation of product with less metal residue, as well as reusability of the high-cost catalysts. Although great effort has been spent, the precise catalytic mechanism of supported metal-catalyzed reactions has not been clearly elucidated and the development of efficient and stable recyclable catalysts remains challenging. This highlight reveals a “molecular fence” metal stabilization strategy and discloses the metal evolution in Pd-catalyzed C–C bond formation reactions using N-heterocyclic carbene (NHC)-functionalized hypercrosslinked polymer support, wherein the polymeric skeleton isolates or confines the metal species involved in the catalytic reactions, and NHC captures free low-valent metal species in solution and stabilizes them on the support via strong metal-support coordination interaction. This strategy creates a novel route for the development of supported metal catalysts with high stability and provides insights into the reaction mechanism of heterogeneous catalysis.

Wearable electronics: electrodes healable by water Wearable electronic devices are susceptible to degradation or fatigue fracture, but now the aged electrodes of the devices can be healed by simple water vapor treatment. A group of international researchers led by Prof Lifeng Cui from Dongguan University of Technology, China designs repairable microfiber-based network electrodes with high conductivity, high transparency and ultra-flexibility. The electrodes consist of polycaprolactone microfibers as healing agents and a thin conducting layer coating such as gold. The electrodes can recover the conductivity and mechanical strength after tensile failure or even cutting, which can be attributed to the adhesion and capillary force at the interface of gold and polymer. Upon embedding in PDMS elastomer, the electrodes show excellent durability of up to 1000 cycles and can be used in wearable pressure and strain sensing devices.

Abstract Silicone (Si) is one type of anode materials with intriguingly high theoretical capacity. However, the severe volume change associated with the repeated lithiation and delithiation processes hampers the mechanical/electrical integrity of Si anodes and hence reduces the battery's cycle‐life. To address this issue, sequence‐defined peptoids are designed and fabricated with two tailored functional groups, “OH” and “COOH”, as cross‐linkable polymeric binders for Si anodes of LIBs. Experimental results show that both the capacity and stability of such peptoids‐bound Si anodes can be significantly improved due to the decreased cracks of Si nanoparticles. Particularly, the 15‐mer peptoid binder in Si anode can result in a much higher reversible capacity (ca. 3110 mAh g−1) after 500 cycles at 1.0 A g−1 compared to other reported binders in literature. According to the density functional theory (DFT) calculations, it is the functional groups presented on the side chains of peptoids that facilitate the formation of Si−O binding efficiency and robustness, and then maintain the integrity of the Si anode. The sequence‐designed polymers can act as a new platform for understanding the interactions between binders and Si anode materials, and promote the realization of high‐performance batteries.

The reverse water-gas shift reaction (RWGSR), a crucial stage in the conversion of abundant CO2 into chemicals or hydrocarbon fuels, has attracted extensive attention as a renewable system to synthesize fuels by non-traditional routes. There have been persistent efforts to synthesize catalysts for industrial applications, with attention given to the catalytic activity, CO selectivity, and thermal stability. In this review, we describe the thermodynamics, kinetics, and atomic-level mechanisms of the RWGSR in relation to efficient RWGSR catalysts consisting of supported catalysts and oxide catalysts. In addition, we rationally classify, summarize, and analyze the effects of physicochemical properties, such as the morphologies, compositions, promoting abilities, and presence of strong metal-support interactions (SMSI), on the catalytic performance and CO selectivity in the RWGSR over supported catalysts. Regarding oxide catalysts (i.e., pure oxides, spinel, solid solution, and perovskite-type oxides), we emphasize the relationships among their surface structure, oxygen storage capacity (OSC), and catalytic performance in the RWGSR. Furthermore, the abilities of perovskite-type oxides to enhance the RWGSR with chemical looping cycles (RWGSR-CL) are systematically illustrated. These systematic introductions shed light on development of catalysts with high performance in RWGSR.

In this study, a high-efficiency photocatalyst was synthesized by Mn2+-doped ZnO nanofibres (NFs) fabricated by facile electrospinning and a following annealing process, in which Mn2+ successes incorporate to ZnO NFs lattice without changing any morphology and crystalline structure of ZnO. The photodegradation properties of ZnO loading with different concentrations of Mn2+ (5, 10, 15 and 50 at%) were investigated. The 50% MnO–ZnO composite owns excellent active photocatalytic performance (quantum efficiency up to 7.57%) compared to pure ZnO (0.16%) under visible light and can be considered as an efficient visible light photocatalyst material. We systematically analysed its catalytic mechanism and found that the enhancement belongs to the Mn doping effect and the phase junction between MnO and ZnO. The dominant mechanism of Mn doping leads to the presence of impurity levels in the band gap of ZnO, narrowing the optical band gap of ZnO. In addition, doped Mn2+ ions can be used as electron traps that inhibit the recombination process and promote electron–hole pair separation. In summary, this paper provides a convenient method for fabricating highly efficient visible light photocatalysts using controlled annealing.

Ovarian cancer is the most lethal malignancy among gynecological cancers worldwide. Most ovarian cancer patients are diagnosed at an advanced stage because of non-specific clinical symptoms. The human microbiome plays a crucial role in maintaining the normal physiological and pathological state of the body. With the development of technologies such as DNA and 16S rRNA sequencing, an increasing number of findings on the role of microbiome in cancers are being reported. Microbiome abnormalities are increasingly associated with diseases, including cancer development, and response to therapies. Some studies have shown the relationship between microbiome changes and ovarian cancer. However, the mechanisms underlying this relationship are not yet fully understood. Here, we summarize the key findings in this regard by focusing on estrogen metabolism and host recognition receptors in microorganisms and changes in the gut or pelvic microbiome in patients with ovarian cancer. We further discuss the potential of using the microbiome as a novel biomarker for cancers. We also highlight the possibility to use microorganisms as a treatment modality to enhance the immune system, activate anti-tumor response, mediate chemotherapy resistance, and ameliorate the adverse effects of the treatment.

In this work, we applied the technology of magnetic treatment to the flotation of chalcopyrite. The mechanism of the effect of pre-magnetized butyl xanthate on chalcopyrite flotation was studied using monomineral flotation tests, adsorption tests, conductivity tests, Fourier transform infrared spectroscopy (FTIR), etc. The monomineral flotation test results showed that, after the magnetization pretreatment of butyl xanthate solution, the chalcopyrite flotation recovery was increased by nearly two percentage points, and the dosage was reduced by 4–10 mg/L at the same recovery. The adsorption, FTIR, dissolved oxygen, and conductivity test results all showed that the magnetization pretreatment increased the dissolved oxygen content and promoted the oxidation of butyl xanthate to double xanthate with better selectivity to chalcopyrite. An electrochemical analysis showed that the magnetization pretreatment of butyl xanthate reduced the corrosion potential and corrosion current density of chalcopyrite surface and inhibited the self-corrosion process of chalcopyrite surface. The flotation test results of actual copper sulfide ore showed that pre-magnetized butyl xanthate could increase the copper recovery of copper concentrate by 3.06 percentage points and the sulfur recovery of sulfur concentrate by nearly 3 percentage points, and effectively reduce the mutual content of copper and sulfur concentrates.

The mechanism was proposed of heterogeneous catalytic CO2 absorptions with primary/secondary amines involving ‘catalytic carbamate formation’. Compared with the non-catalytic ‘Zwitterion mechanism’, this Eley–Rideal model was proposed for CO2 + RR′NH with MCO3 (M = Ca, Mg, and Ba) with four elementary reaction steps: (B1) amine adsorption, (B2) Zwitterion formation, (B3) carbamate formation, and (B4) carbamate desorption. The rate law if determining step of each elementary step was generated based on ‘steady-state approximation’. Furthermore, the solid chemicals were characterized by SEM and BET, and this rate model was verified with 39 sets of experimental datasets of catalytic CO2–MEA absorptions with the existence of 0–25 g CaCO3, MgCO3 and BaCO3. The results indicated that the rate-determining step was B1 as amine adsorption onto solid surface, which was pseudo-first-order for MEA. This was the first time that the Eley–Rideal model had been adopted onto the reactions of CO2 + primary/secondary amines over alkaline earth metal carbonate (MCO3).

Porous organic cages (POC) are a class of relatively new molecular porous materials, whose concept was raised in 2009 by Cooper’s group and has rarely been directly used in the area of organic catalysis. In this contribution, a novel ionic quasi-porous organic cage (denoted as Iq-POC), a quaternary phosphonium salt, was easily synthesized through dynamic covalent chemistry and a subsequent nucleophilic addition reaction. Iq-POC was applied as an effective nucleophilic catalyst for the cycloaddition reaction of CO2 and epoxides. Owing to the combined effect of the relatively large molecular weight (compared with PPh3+I−) and the strong polarity of Iq-POC, the molecular catalyst Iq-POC displayed favorable heterogeneous nature (i.e., insolubility) in this catalytic system. Therefore, the Iq-POC catalyst could be easily separated and recycled by simple centrifugation method, and the catalyst could be reused five times without obvious loss of activity. The molecular weight augmentation route in this study (from PPh3+I− to Iq-POC) provided us a “cage strategy” of designing separable and recyclable molecular catalysts.

The fundamental harmonic amplitude and waveform distortion rate of the air-gap flux density directly affect the performance of a permanent magnet spherical motor (PMSM). Therefore, in the paper, the axial air-gap magnetic field including the end leakage of the Halbach array PMSM is analyzed and optimized. In order to reduce the calculation time of the objective function, the air gap magnetic field model adopts a non-linear regression model based on support vector machine (SVM). At the same time, the improved grid search (GS) algorithm is used to optimize the parameters of SVM model, which improves the efficiency and accuracy of parameter optimization. Considering the influence of moment of inertia on the dynamic response of the motor, the moment of inertia of the PMSM is calculated. This paper takes the air gap magnetic density fundamental wave amplitude, waveform distortion rate and rotor moment of inertia as the optimization objectives. The particle swarm optimization (PSO) algorithm is used to optimize the motor structure with multiple objectives. The optimal structure design of the PMSM is selected from all of non-dominated solutions by the technique for order preference by similarity to an ideal solution (TOPSIS). The performance of the motor before and after the optimization is analyzed by the method of finite element (FEM) and experimental verification. The results verify the effectiveness and efficiency of the optimization method for the optimal structure designing of the complex PMSM.

Studies of catalytic CO2 absorption and desorption were completed in two well-performed tertiary amines: diethylmonoethanolamine (DEEA) and 1-dimethylamino-2-propanol (1DMA-2P), with the aid of CaCO3 and MgCO3 in the absorption process, and with the aid of γ-Al2O3 and H-ZSM-5 in the desorption process. The batch process was used for CO2 absorption with solid alkalis, and the recirculation process was used for CO2 desorption with solid acid catalysts. The CO2 equilibrium solubility and pKa were also measured at 293 K with results comparable to the literature. The catalytic tests discovered that the heterogeneous catalysis of tertiary amines on both absorption and desorption sides were quite different from monoethanolamine (MEA) and diethanolamine (DEA). These results were illustrative as a start-up to further study of the kinetics of heterogeneous catalysis of CO2 to tertiary amines based on their special reaction schemes and base-catalyzed hydration mechanism.

In this study, a low-cost and environmentally friendly method is developed to synthesize cobalt and nitrogen co-doped graphene-carbon nanotube aerogel (Co-N-GCA) as a bifunctional electrocatalyst for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). The as-prepared Co-N-GCA has a hierarchical meso- and macroporous structure with a high N doping level (8.92 at. %) and a large specific surface area (456 m2 g−1). In an alkaline medium, the catalyst exhibits superior ORR electrocatalytic activity with an onset potential 15 mV more positive than Pt/C, and its diffusion-limiting current density is 29% higher than that of commercial Pt/C. The obtained Co-N-GCA is also highly active toward the OER, with a small overpotential of 408 mV at a current density of 10 mA cm−2. Its overall oxygen electrode activity parameter (ΔE) is 0.821 V, which is comparable to most of the best nonprecious-metal catalysts reported previously. Furthermore, Co-N-GCA demonstrates superior durability in both the ORR and the OER, making it a promising noble-metal-free bifunctional catalyst in practical applications for energy conversion and storage.

In this work, Ag–Fe2O3 catalysts were successfully prepared using several different methods. Our main intention was to investigate the effect of the preparation methods on the catalysts’ structure and their catalytic performance for CO oxidation. The catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), H2-temperature program reduction (H2-TPR) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Ag–Fe catalysts prepared by impregnating Ag into MIL-100 (Fe) presented the best catalytic activity, over which CO could be completely oxidized at 160 °C. Based on the characterization, it was found that more metallic Ag species and porosity existed on Ag–Fe catalysts, which could efficiently absorb atmospheric oxygen and, thus, enhance the CO oxidation.

Preeclampsia is a multi-system disorder involved in pregnancy without an effective treatment except delivery. The precise pathogenesis of this complicated disorder is still not completely understood. The objective of this study is to evaluate the alterations of protein expression and phosphorylations that are important in regulating placental cell function in preterm and term preeclampsia. Using the Protein Pathway Array, 38 proteins in placental tissues were found to be differentially expressed between preterm preeclampsia and gestational age matched control, while 25 proteins were found to be expressed differentially between term preeclampsia and matched controls. Among these proteins, 16 proteins and their associated signaling pathways overlapped between preterm and term preeclampsia, suggesting the common pathogenesis of two subsets of disease. On the other hand, many proteins are uniquely altered in either preterm or term preeclampsia and correlated with severity of clinical symptoms and outcomes, therefore, providing molecular basis for these two subsets of preeclampsia. Furthermore, the expression levels of some of these proteins correlated with neonatal small for gestational age (PAI-1 and PAPP-A) and adverse outcomes (Flt-1) in women with preterm preeclampsia. These proteins could potentially be used as candidate biomarkers for predicting outcomes of preeclampsia.

Catalysts made of CuO/Bi2O3 nanoparticles supported on g-C3N4 were synthesized using a MOF-derived strategy. The activation of CuO to CuCuCCu species and stabilization of the catalyst were facilitated by the synergistic effect of the CuO/C3N4 interface and CuO nanoparticles, resulting in enhanced catalytic efficacy in the ethynylation of formaldehyde. [ABSTRACT FROM AUTHOR]

OER/ORR dual-functional electrocatalyst is an important part of the metal-air battery module. Although noble metal materials such as Ru and Ir have excellent catalytic performance in oxygen reduction reaction (ORR) and hydrogen evolution reaction (OER), their cost limits their large-scale application. Therefore, it is necessary to develop OER/ORR dual-functional electrocatalyst with low cost, abundant reserves, and excellent catalytic performance. This review summarizes the characteristics and research progress of non-noble metal carbon-based bifunctional electrocatalysts, and summarizes the effects of various surface modification methods on their properties. At the same time, the prospect of carbon-based bifunctional electrocatalysts is also discussed. Finally, we think this review could provide suggestions for the development of non-metallic carbon-based bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]