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Relocation of captive giant pandas refers to releasing captive-bred giant pandas to the wild with the aim of bolstering and restoring the wild panda population. This method should be one of the key approaches adopted as part of conservation measures implemented for this endangered species. Compared to translocation of wild pandas to a new place, relocation of captive-bred pandas faces more difficulties and challenges. At present, giant panda relocation programs are still at the exploration stage in China. Focusing on captive-bred giant pandas, individual animal traits are discussed here. It is indicated that a well-managed husbandary system which enables the captive pandas to develop normally as wild ones is one of the key factors for relocation programs. Accordingly, based on some latest achievements, some measures to improve husbandary management are presented. This summary provides scientific data concerning ongoing giant panda reintroduction work, particularly on selecting animals for reintroduction and on training animals for release. [ABSTRACT FROM AUTHOR]

The major challenges of aqueous zinc‐ion batteries (ZIBs) are the dendrite formation and the passivation of zinc metal anode, which restrict their practical applications. Herein, polyacrylonitrile (PAN) and zwitterionic surfactant (Sulfobetaine methacrylate, SBMA) are combined as a precursor to design a modified PAN nanofiber separator by electrospinning. SBMA with sulfonate group [SO3−] can alter the physical property of the precursor solution and electrostatic field during the electrospinning process. Besides, it can regulate the zinc ions crossing and homogenize the electric field by minimizing the zinc ion concentration polarization on the zinc foil surface due to the polar group. As a result, Zn symmetric cells with PAN@SBMA separators show long‐term stability (up to 1700 h), which outdistances the cell with GF‐D (only up to 50 h) under current density at 1 mA cm−2. Meanwhile, the Zn//PAN@SBMA//NH4V4O10 full cells have high specific capacity (236 mAh g−1) and excellent long‐term durability with 84.2% capacity retention after 2000 cycles at 5 A g−1. This work illustrates an easy and effective way to design a high ion transference number and functional PAN‐based separator for regulating Zn2+ deposition for the development of high‐performance ZIBs. [ABSTRACT FROM AUTHOR]

Formaldehyde (HCHO) is the main source of indoor air pollutant. HCHO sensors are therefore of paramount importance for timely detection in daily life. However, existing sensors do not meet the stringent performance targets, while deactivation due to sensing detection at room temperature, for example, at extremely low concentration of formaldehyde (especially lower than 0.08 ppm), is a widely unsolved problem. Herein, we present the Ag nanoparticles (Ag NPs) sensitized dispersed In2O3 nanograin via a low-fabrication-cost hydrothermal strategy, where the Ag NPs reduces the apparent activation energy for HCHO transporting into and out of the In2O3 nanoparticles, while low concentrations detection at low working temperature is realized. The pristine In2O3 exhibits a sluggish response (Ra/Rg = 4.14 to 10 ppm) with incomplete recovery to HCHO gas. After Ag functionalization, the 5%Ag-In2O3 sensor shows a dramatically enhanced response (135) with a short response time (102 s) and recovery time (157 s) to 1 ppm HCHO gas at 30 °C, which benefits from the Ag NPs that electronically and chemically sensitize the crystal In2O3 nanograin, greatly enhancing the selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

The rational design of heterojunction between different metal oxides with mesoporous structures has attracted tremendous attention due to their special physicochemical properties and vital importance for practical applications. In this paper, mesoporous Ag/Zn–LaFeO3 nanocomposite is successfully synthesized through a facile nanocasting technique using KIT‐6 as a hard template in sol–gel route and used as sensing materials to achieve an exceptionally sensitive and selective detection of trace ppm‐level ethanol. The obtained composite possesses high surface area and exhibits excellent sensing response (64.2 for 100 ppm) to ethanol at near‐room with relatively fast response/recovery time. When tested with the concentrations as low as 5 ppm, it also shows a remarkably high selectivity to the ethanol, but only minor responses to other interfering gases. These enhanced gas‐sensing properties are attributed to the combination of mesoporous nanostructure and Ag/Zn–LaFeO3 heterogeneous composites. Perovskite type metal oxide semiconductors are developed for application of gas sensors due to their numerous favorable physical/chemical properties. LaFeO3 shows considerably sensitive to reducing gases, but it still has some deficiencies. Mesoporous Ag/Zn–LaFeO3 nanocomposite synthesized through facile nanocasting technique is used as a sensing material to achieve sensitive and selective detection of trace ppm‐level ethanol at near‐room temperature. [ABSTRACT FROM AUTHOR]

Lightweight and highly compressible materials have received considerable attention in flexible pressure sensing devices. In this study, a series of porous woods (PWs) are produced by chemical removal of lignin and hemicellulose from natural wood by tuning treatment time from 0 to 15 h and extra oxidation through H 2 O 2 . The prepared PWs with apparent densities varying from 95.9 to 46.16 mg/cm 3 tend to form a wave-shaped interwoven structure with improved compressibility (up to 91.89 % strain under 100 kPa). The sensor assembled from PW with treatment time of 12 h (PW-12) exhibits the optimal piezoresistive-piezoelectric coupling sensing properties. For the piezoresistive properties, it has high stress sensitivity of 15.14 kPa -1 , covering a wide linear working pressure range of 0.06-100 kPa. For its piezoelectric potential, PW-12 shows a sensitivity of 0.443 V·kPa -1 with ultralow frequency detection as low as 0.0028 Hz, and good cyclability over 60,000 cycles under 0.41 Hz. The nature-derived all-wood pressure sensor shows obvious superiority in the flexibility for power supply requirement. More importantly, it presents fully decoupled signals without cross-talks in the dual-sensing functionality. Sensor like this is capable of monitoring various dynamic human motions, making it an extremely promising candidate for the next generation artificial intelligence products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Myocardial microvascular injury is the key event in early diabetic heart disease. The injury of myocardial microvascular endothelial cells (CMECs) is the main cause and trigger of myocardial microvascular disease. Mitochondrial calcium homeostasis plays an important role in maintaining the normal function, survival and death of endothelial cells. Considering that mitochondrial calcium uptake 1 (MICU1) is a key molecule in mitochondrial calcium regulation, this study aimed to investigate the role of MICU1 in CMECs and explore its underlying mechanisms., Methods: To examine the role of endothelial MICU1 in diabetic cardiomyopathy (DCM), we used endothelial-specific MICU1 ecKO mice to establish a diabetic mouse model and evaluate the cardiac function. In addition, MICU1 overexpression was conducted by injecting adeno-associated virus 9 carrying MICU1 (AAV9-MICU1). Transcriptome sequencing technology was used to explore underlying molecular mechanisms., Results: Here, we found that MICU1 expression is decreased in CMECs of diabetic mice. Moreover, we demonstrated that endothelial cell MICU1 knockout exacerbated the levels of cardiac hypertrophy and interstitial myocardial fibrosis and led to a further reduction in left ventricular function in diabetic mice. Notably, we found that AAV9-MICU1 specifically upregulated the expression of MICU1 in CMECs of diabetic mice, which inhibited nitrification stress, inflammatory reaction, and apoptosis of the CMECs, ameliorated myocardial hypertrophy and fibrosis, and promoted cardiac function. Further mechanistic analysis suggested that MICU1 deficiency result in excessive mitochondrial calcium uptake and homeostasis imbalance which caused nitrification stress-induced endothelial damage and inflammation that disrupted myocardial microvascular endothelial barrier function and ultimately promoted DCM progression., Conclusions: Our findings demonstrate that MICU1 expression was downregulated in the CMECs of diabetic mice. Overexpression of endothelial MICU1 reduced nitrification stress induced apoptosis and inflammation by inhibiting mitochondrial calcium uptake, which improved myocardial microvascular function and inhibited DCM progression. Our findings suggest that endothelial MICU1 is a molecular intervention target for the potential treatment of DCM., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Tin-based gas sensors have been developed for many years owing to their advantages of low price, high response and stability. However, selectivity remains a significant issue. Herein, Ag-SnO 2 nanofibers are synthesized using AgCl as the doping reagent. The 3%Ag-SnO 2 nanofibers sensors show a high response of 68 toward 1 ppm H 2 S at 90 °C. Besides, the sensor with 3% AgCl possesses the shortest response time about 136 s at 150 °C which is only 30% value of the sensor without AgCl doping. It is also demonstrated that the nanofibers show a high selectivity towards H 2 S. According to the ex situ x-ray photoelectron spectrum and x-ray diffraction results, AgCl was transferred to Ag 2 S after Ag-SnO 2 was exposed to H 2 S, and reversible transformation between Ag 2 SO 4 and Ag 2 S was the main mechanism for H 2 S detection. Compared with pure SnO 2 nanofiber sensors, the presence of Ag 2 S with high conductivity greatly affects the resistance to H 2 S, resulting in high selectivity and response. This mechanism differs from that of the transformation between Ag 2 O and Ag 2 SO 4 . This study may provide a new strategy for the design and investigation of sensors with high selectivity., (© 2023 IOP Publishing Ltd.)

Background: A number of models have been reported for predicting atrial fibrillation (AF) recurrence after catheter ablation. Although many machine learning (ML) models were developed among them, black-box effect existed widely. It was always difficult to explain how variables affect model output. We sought to implement an explainable ML model and then reveal its decision-making process in identifying patients with paroxysmal AF at high risk for recurrence after catheter ablation., Methods: Between January 2018 and December 2020, 471 consecutive patients with paroxysmal AF who had their first catheter ablation procedure were retrospectively enrolled. Patients were randomly assigned into training cohort (70%) and testing cohort (30%). The explainable ML model based on Random Forest (RF) algorithm was developed and modified on training cohort, and tested on testing cohort. In order to gain insight into the association between observed values and model output, Shapley additive explanations (SHAP) analysis was used to visualize the ML model., Results: In this cohort, 135 patients experienced tachycardias recurrences. With hyperparameters adjusted, the ML model predicted AF recurrence with an area under the curve of 66.7% in the testing cohort. Summary plots listed the top 15 features in descending order and preliminary showed the association between features and outcome prediction. Early recurrence of AF showed the most positive impact on model output. Dependence plots combined with force plots showed the impact of single feature on model output, and helped determine high risk cut-off points. The thresholds of CHA 2 DS 2 -VASc score, systolic blood pressure, AF duration, HAS-BLED score, left atrial diameter and age were 2, 130 mmHg, 48 months, 2, 40 mm and 70 years, respectively. Decision plot recognized significant outliers., Conclusion: An explainable ML model effectively revealed its decision-making process in identifying patients with paroxysmal atrial fibrillation at high risk for recurrence after catheter ablation by listing important features, showing the impact of every feature on model output, determining appropriate thresholds and identifying significant outliers. Physicians can combine model output, visualization of model and clinical experience to make better decision., (© 2023. The Author(s).)

Formaldehyde is a common carcinogen in daily life and harmful to health. The detection of formaldehyde by a metal oxide semiconductor gas sensor is an important research direction. In this work, cobalt-doped SnO 2 nanoparticles (Co-SnO 2 NPs) with typical zero-dimensional structure were synthesized by a simple hydrothermal method. At the optimal temperature, the selectivity and response of 0.5% Co-doped SnO 2 to formaldehyde are excellent (for 30 ppm formaldehyde, R a / R g = 163 437). Furthermore, the actual minimum detectable concentration of 0.5%Co-SnO 2 NPs is as low as 40 ppb, which exceeds the requirements for formaldehyde detection in the World Health Organization (WHO) guidelines. The significant improvement of 0.5%Co-SnO 2 NPs gas performance can be attributed to the following aspects: firstly, cobalt doping effectively improves the resistance of SnO 2 NPs in the air; moreover, doping creates more defects and oxygen vacancies, which is conducive to the adsorption and desorption of gases. In addition, the crystal size of SnO 2 NPs is vastly small and has unique physical and chemical properties of zero-dimensional materials. At the same time, compared with other gases tested, formaldehyde has a strong reducibility, so that it can be selectively detected at a lower temperature., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Here we report a mesoporous TiO 2 with a large specific surface area and rich oxygen vacancies using a Ti-based MOF (MIL-125) as a precursor through high-temperature annealing. Such integration of a unique mesoporous structure and oxygen vacancies provides effective carrier transport channels, increases surface active sites, and enhances photocatalytic activity for the hydrogen evolution reaction.

Xylene is a volatile organic compound which is harmful to the human health and requires precise detection. The detection of xylene by an oxide semiconductor gas sensor is an important research direction. In this work, Co 3 O 4 decorated flower-like SnO 2 nanorods (SnO 2 /Co 3 O 4 NRs) were synthesized by a simple and effective two-step method. The SnO 2 /Co 3 O 4 NRs show high xylene response (R g /R a  = 47.8 for 100 ppm) and selectivity at the operating temperature of 280 °C, and exhibit high stability in continuous testing. The resulting SnO 2 /Co 3 O 4 NRs nanocomposites show superior sensing performance towards xylene in comparison with pure SnO 2 nanorods. The remarkable enhancement in the gas-sensing properties of SnO 2 /Co 3 O 4 NRs are attributed to larger specific surface area and the formation of p-n heterojunction between Co 3 O 4 and SnO 2 . These results demonstrate that particular nanostructures and synergistic effect of SnO 2 and Co 3 O 4 enable gas sensors to selectively detect xylene.

A concise, catalytic, and general strategy that allowed efficient total syntheses of 22 natural 13-methylprotoberberines within four steps for each molecule is reported. This synthesis represents the most efficient and shortest route to date, featuring three catalytic processes: CuI-catalyzed redox-A(3) reaction, Pd-catalyzed reductive carbocyclization, and PtO2 -catalyzed hydrogenation. Importantly, this new strategy to the tetracyclic framework has also been applied to the collective concise syntheses of >30 natural protoberberines (without 13-methyl group) and five aporhoeadane alkaloids., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The total synthesis of (-)-goniomitine has been accomplished in 11 steps starting from commercially available diethyl l-malate. The synthesis features a chiral pool approach to prepare the chiral C-9 unit containing a quaternary carbon center, an Ir-catalyzed C-H borylation to synthesize the 2-indoleboronic acid pinacol ester, and a Suzuki reaction to couple together the two key intermediates. Notably, the high degree of convergence of this strategy makes it particularly amenable to the total synthesis of other aspidosperma family natural products.