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A planar Marchand balun for wideband performance is presented. The two sections of quarter‐wavelength parallel‐coupled lines are etched in the bottom ground layer for a higher coupling coefficient. In the top metal layer, the additional compensation‐transmission‐line Trace is designed between the two balanced ports to decrease the imbalances. Two different frequency band circuits Balun A&B have been simulated and fabricated to verify the design method of this letter. The results of simulation and measurement show that the balun structure can achieve high amplitude and phase stability over a wide frequency band (the Balun A is from 1.5 to 4.8 GHz, with the relative bandwidth of 104.7% and the Balun B is from 2.3 to 7.3 GHz, with the relative bandwidth of 104.1%. [ABSTRACT FROM AUTHOR]

The bistatic synthetic aperture radar (BiSAR) plays an important role in remote sensing. However, the deviation between the two oscillators in BiSAR systems will cause a residual modulation of the echo signal. Therefore, the phase synchronization is an important issue that must be addressed in the BiSAR system. An advanced noninterrupted phase synchronization scheme is used for LuTan-1. The synchronization pulses are exchanged immediately after the ending time of the radar echo receiving window and before the starting time of the next pulse repetition interval, which will not interrupt the normal SAR operation. In order to evaluate the accuracy of the phase synchronization scheme, the model of phase synchronization is introduced at first. The hardware design and processing flow of LuTan-1 are introduced in detail. An innovative internal calibration strategy is also described. Then, the test data acquired by the ground validation system are analyzed to verify the effectiveness of the phase synchronization scheme. The signal-to-noise ratio (SNR) and the synchronization rate are the two most important factors to influence the accuracy in phase synchronization. The conclusions have guiding significance for the synchronization module design of LuTan-1 and the future BiSAR system. [ABSTRACT FROM AUTHOR]

In recent years, jamming strategies for Synthetic Aperture Radar (SAR) pertaining to target detection and identification, such as the creation of false targets, electromagnetic (EM) deception, and signal spoofing, have been increasingly emphasized. Distinct from traditional SAR jamming approaches, the introduction of an innovative artificial material cloak in SAR target jamming presents augmented capabilities. These methods demonstrate a proficient redirection of incident EM waves in specific or arbitrary directions, effectively masking the vital information linked to critical targets. This study introduces a broadband SAR target jamming system employing an information metasurface that incorporates intelligent information processing algorithms in conjunction with a space-time-coding digital metasurface, endowing it with the capacity to adeptly modulate incident EM waves. This integration facilitates a versatile approach to jamming, enabling the deployment of multi-mode protective measures against critical targets. The conducted simulation and experiment results validate the system's ability to adjustably produce EM deception and generate multiple false targets independently of the SAR system. The outcomes of this research significantly advance the practicality of SAR protection strategies, pushing the boundaries toward more dynamic, broadband, and controllable scenarios, thereby substantially improving the concealment of critical targets in highly sensitive conflict areas. [ABSTRACT FROM AUTHOR]

Rice blast, caused by the fungus Magnaporthe oryzae, and brown planthopper (BPH) infestation are two of the most destructive problems of rice production in China. The development of multi-resistant varieties is widely recognized as the most efficient and environmentally friendly approach to controlling crop diseases and pests. Functional molecular markers (FMMs) have been developed from functional variants in the genic region associated with trait variation, greatly enhancing the efficiency of identifying and pyramiding valuable genes in crop breeding. In this study, two FMMs and a multiplex PCR amplification system were developed for two major broad-spectrum BPH resistance genes, Bph6 and Bph9. With the assistance of FMMs in the multi-resistant rice restorer-line development pipeline, two lines (Huahui7713 and Huahui3006) with blast and BPH resistance were developed by pyramiding three resistance genes Pigm, Bph6 and Bph9. Two new hybrid rice varieties, Weiliangyou7713 and Xuanliangyou3006, derived from Huahui7713 and Huahui3006, have been developed and commercialized in China. Weiliangyou7713 and Xuanliangyou3006 exhibit enhanced resistance to both blast and BPH, while maintaining optimal yield and grain quality. The adoption of Weiliangyou7713 continues to expand, now being cultivated on a large scale, which is promising for its future role in reducing the dependence on chemical fungicides and pesticides in rice production. This suggests that the implementation of Huahui7713 and Huahui3006 in targeted breeding programs could be highly beneficial for developing rice varieties with strong resistance to blast and BPH. [ABSTRACT FROM AUTHOR]

Although many risk factors for cage retropulsion (CR) after lumbar interbody fusion (LIF) have been described in the literature, they still remain controversial. The purpose of this study is to investigate the risk factors for CR after LIF. The literature was searched in PubMed, Cochrane library, and Embase from October 2000 to October 2018. The key words and combinations used in the search included LIF, cage, retropulsion, posterior migration, and risk factors. Only studies with sufficient data to calculate odds ratio for CR were included. Odds ratio and 95% confidence interval were calculated for outcomes via RevMan5.3 and SPSS 22.0. A total of 10 studies were included in this study. Twelve risk factors were assessed by analyzing 4467 patients. The pooled results indicated that a pear-shaped disk and straight cage were significant risk factors for CR. However, factors that had no significant relation with CR were preoperative diagnosis (disk herniation, spinal stenosis, and spondylolisthesis); gender; surgical segments (from L2 to S1); multilevel fusion; and unilateral pedicle screws fixation. According to current evidence, a pear-shaped disk and straight cage are significant risk factors for CR. However, preoperative diagnosis, gender, multilevel fusion, surgical segments, and unilateral pedicle screws fixation are not the risk factors associated with CR. A revision surgery is needed when neurologic symptoms happen after CR. The conclusion should be consulted cautiously due to the limited number of included studies. Therefore larger-scale studies are still needed to investigate the risk factors for CR. [ABSTRACT FROM AUTHOR]

Pescadillo (PES1) is a key molecule for ribosome formation in mammalian cells. In this study, human hepatoma C3A cells were reprogrammed by four transcription factors, Oct4, Sox2, Klf4 and c‐Myc, into induced cancer stem cells, termed C3A‐induced cancer stem cells (C3A‐iCSCs). We found that PES1 was up‐regulated in C3A‐iCSCs and promoted cell proliferation. Moreover, the cancer stem cell marker CD44, which is located in the cytomembrane, translocated to the nucleus and was up‐regulated in C3A‐iCSCs. Our results suggest that CD44 has a negative effect on miR‐105‐5p. We found that PES1 is a direct target of, and was negatively regulated by, miR‐105‐5p. In summary, CD44 regulates PES1 in liver cancer stem cells via miR‐105‐5p to promote cell growth. [ABSTRACT FROM AUTHOR]

In recent years，different types of self-suspending proppants have come up. Among these proppants, “fracturing fluid coated” self-suspending proppant, which can adopt different types of proppants, is evaluated experimentally in this research. Evaluation standards and methods for this “fracturing fluid coated” proppant are discussed firstly. Suspension parameters are essential indicators of performance evaluation, the final proppant settlement volume and deposition time consumed from uniform mixture to the final volume under relative sensitive experiment conditions are selected as evaluation indexes. Influence of different factors on proppant suspension is evaluated by experiments, and corresponding results make the application scope of self-suspending proppant clear. [ABSTRACT FROM AUTHOR]

Evolution of pest resistance reduces the efficacy of insecticidal proteins from the gram-positive bacterium Bacillus thuringiensis (Bt) used widely in sprays and transgenic crops. Recent efforts to delay pest adaptation to Bt crops focus primarily on combinations of two or more Bt toxins that kill the same pest, but this approach is often compromised because resistance to one Bt toxin causes cross-resistance to others. Thus, integration of Bt toxins with alternative controls that do not exhibit such cross-resistance is urgently needed. The ideal scenario of negative cross-resistance, where selection for resistance to a Bt toxin increases susceptibility to alternative controls, has been elusive. Here we discovered that selection of the global crop pest, Helicoverpa armigera, for >1000-fold resistance to Bt toxin Cry1Ac increased susceptibility to abamectin and spineotram, insecticides derived from the soil bacteria Streptomyces avermitilis and Saccharopolyspora spinosa, respectively. Resistance to Cry1Ac did not affect susceptibility to the cyclodiene, organophospate, or pyrethroid insecticides tested. Whereas previous work demonstrated that the resistance to Cry1Ac in the strain analyzed here is conferred by a mutation disrupting an ATP-binding cassette protein named ABCC2, the new results show that increased susceptibility to abamectin is genetically linked with the same mutation. Moreover, RNAi silencing of HaABCC2 not only decreased susceptibility to Cry1Ac, it also increased susceptibility to abamectin. The mutation disrupting ABCC2 reduced removal of abamectin in live larvae and in transfected Hi5 cells. The results imply that negative cross-resistance occurs because the wild type ABCC2 protein plays a key role in conferring susceptibility to Cry1Ac and in decreasing susceptibility to abamectin. The negative cross-resistance between a Bt toxin and other bacterial insecticides reported here may facilitate more sustainable pest control. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to evaluate the influence of high nerve tension on lumbar disc degeneration and sagittal morphologies. A total of 50 young and middle-aged patients (mean age 32.1 ± 7.4 years, 22 men and 28 women) who suffered from tethered cord syndrome (TCS) were retrospectively assessed by two observers. Demographic and radiological data were recorded, including lumbar disc degeneration, disc height index and lumbar spine angle, and were compared with 50 patients (mean age 29.7 ± 5.4 years, 22 men and 28 women) without spinal cord abnormalities. Statistical associations were assessed by student's t-test and chi-square test. Our results showed patients with TCS had a significantly higher rate of lumbar disc degeneration in L1/2, L2/3, L4/5 and L5/S1 than in those without TCS (P < 0.05). Moreover, the rates of multilevel disc degeneration and severe disc degeneration in TCS group were significantly higher than those in control group (P < 0.01). The mean disc height index of L3/4 and L4/5 in TCS group was significantly lower than that in control group (P < 0.05). The mean lumbosacral angle of TCS patients was significantly higher than that of patients without TCS (38.4 ± 3.5°vs. 33.7 ± 5.9°, P < 0.01). We found a certain correlation between TCS and lumbar disc degeneration and lumbosacral angle enlargement, suggesting that the spine reduces the high tension of the spinal cord through disc degeneration. Therefore, it is speculated that there is a "compromised regulation" mechanism in the body under the condition of neurological abnormalities. [ABSTRACT FROM AUTHOR]

One dimensional porous NiO-decorated Co 3 O 4 composites were synthesized via a two-step solution-based method. The composites were detected by X-ray photoelectron spectroscopy (XPS), and it shows that the atomic ratio of nickle is about 1.74% in the composite. The obtained NiO-decorated Co 3 O 4 composite yields a high specific capacitance of 1112 F g −1 at a current density of 2 A g −1 , exhibits perfect rate and cycling stability. Furthermore, the specific capacitance of the composite can still keep a good retention of 97% after 1000 cycles at 2 A g −1 , demonstrating the excellent long-term electrochemical stability of the composite. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we discuss global asymptotic stability to a BAM neural networks of neutral type with delays. Under the assumptions that the activation functions only satisfy global Lipschitz conditions, a new and complicated LMI condition is established on global asymptotic stability for the above neutral neural networks by means of using Homeomorphism theory, matrix and Lyapunov functional. In our result, the hypotheses for boundedness in and monotonicity in on the activation functions are removed. On the other hand, the LMI condition is also different from those in . Finally, an example is given to show the effectiveness of the theoretical result. [Copyright &y& Elsevier]

Abstract: In this paper, we first investigate the existence of a periodic solution to interval general bidirectional associative memory (BAM) neural networks with multiple delays on time scales by the continuation theorem of coincidence degree theory. Then, by constructing a Lyapunov functional, we discuss the global exponential stability of the periodic solution for such neural networks on time scales. The paper unifies periodic discrete-time and continuous-time BAM neural networks under the same framework. [Copyright &y& Elsevier]

Abstract: Monoclinic Li3V2−x Al x (PO4)3 with different Al3+ doping contents (x =0, 0.05, 0.08, 0.10 and 0.12) have been prepared by a facile aluminothermal reaction. Aluminum nanoparticles have been used as source for Al3+ and nucleus for Li3V2−x Al x (PO4)3 nucleation as well as reducing agent in the aluminothermal strategy. The products were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and electrochemical methods. The XRD results show that the as-obtained Li3V2−x Al x (PO4)3 has a phase-pure monoclinic structure, irrespective of the Al3+ doping concentration. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) results reveal that the charge-transfer resistance of the Li3V2(PO4)3 is reduced and the reversibility is enhanced after V3+ substituted by Al3+. In addition, The Li3V2−x Al x (PO4)3 phases exhibit better cycling stability than the pristine Li3V2(PO4)3. [Copyright &y& Elsevier]

Mitochondria are involved in apoptosis of mammalian cells and even single-cell organisms, but mitochondria are not required in apoptosis in cultured Drosophila cells such as S2 and BG2 cell lines. It is not very clear whether mitochondria are involved in apoptosis in other insect cells such as lepidopteran cell lines. Thus, we determined to elucidate the role of mitochondria in apoptosis induced by ultraviolet radiation in Spodoptera litura (Lepidoptera: Noctuidae) cell line (SL-ZSU-1). The Western blot results suggested that cytochrome c in the ultraviolet-treated SL-1 cells was released from the mitochondria to cytosol as early as 4 h after the induction of ultraviolet radiation and increased in the cytosolic fractions in a time-dependent manner. Flow cytometric analysis of mitochondrial membrane potential (ΔΨm) of SL-ZSU-1 cell treated with ultraviolet-C (UV-C) light indicated the decrease in mitochondrial membrane potential was dependent on the times of ultraviolet treatment. Both of them are different from apoptosis in cultured Drosophila melanogaster cell lines (S2 and BG2) and it appears evident mitochondria are involved in apoptosis of the studied lepidopteran cells. [ABSTRACT FROM AUTHOR]

Abstract: Based on Lyapunov–Krasovskii stability theory and the linear matrix inequality (LMI) technique, a criterion is derived to guarantee the global exponential stability of the class of delayed neural networks with time-varying delays, which generalizes and improves previous results. Numerical examples demonstrate the effectiveness of the criterion. [Copyright &y& Elsevier]

Abstract: Offset fluvial valleys, including rivers beheaded and deflected by strike-slip faults, have long been used to estimate horizontal displacements on the faults. Larger rivers crossing such faults, however, sometimes show either no offset or only a small amount of offset compared to smaller rivers crossing the same faults. The larger rivers with higher erosional rates may widen their valleys asymmetrically downstream of strike-slip faults, rather than being beheaded or deflected. Examples are described from the Yellow River near the NE margin of the Tibetan Plateau. River beheading and asymmetrical widening are two end-members of a fluvial valley''s response to strike-slip faulting, whereas deflection is a combination of both. Recognition of the formation of such asymmetrical valleys related to strike-slip faulting will help to understand fault activity better over longer time spans and enable a re-evaluation of many fault histories worldwide. [Copyright &y& Elsevier]

The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa. The insecticidal protein Vip3Aa is used in genetically engineered crops to overcome pest resistance to other insecticidal transgenes. This study shows that insertion of a transposable element into a gut-specific chitin synthase gene causes Vip3Aa resistance in field-collected individuals of the lepidopteran pest Spodoptera frugiperda (fall armyworm). [ABSTRACT FROM AUTHOR]

A study published in the journal Clinical & Translational Medicine suggests that analyzing microbial communities could be a useful tool for diagnosing and predicting the prognosis of pancreatic tumors. The researchers examined fecal and intratumor microbial samples from patients with pancreatic tumors and healthy volunteers. They discovered that specific bacteria in fecal samples could potentially serve as non-invasive biomarkers for early detection of pancreatic tumors. Furthermore, they observed differences in the microbial composition of pancreatic tissues between malignant and non-malignant tumors. These findings indicate that microbial profiling may offer a promising approach for improving the early detection and treatment of pancreatic tumors. [Extracted from the article]

Abstract: The excess molar enthalpies () for the binary mixtures of trimethyl phosphate (TMP) with alkanols {CH3(CH2) n OH, n =0–3} have been measured with an isothermal calorimeter at 298.15K and atmospheric pressure. The values are positive for all the mixtures over the whole composition range. The values increase in the order methanol

Background: The relationship between serum lipids and cholecystitis is still under investigation. To examine the causal effect of serum lipids on cholecystitis using the Mendelian randomization method. Methods: We conducted univariable Mendelian randomization (MR) analyses using summary statistics from two independent genome-wide association studies (GWAS) on serum lipids (n = 132,908) and cholecystitis (n = 361,194). Mainly, the inverse-variance weighted (IVW) method was utilized to combine each SNP's causal estimation, and the MR-Egger was adopted as a complementary method, together with the weighted median. Cochrane's Q value was employed to appraise heterogeneity. The MR-Egger intercept and MR-PRESSO were used to detect the horizontal pleiotropy. Results: Our univariable results displayed a minor protective effect of serum low-density lipoprotein (LDL) cholesterol (OR [95% CI] = 0.9984483 [0.9984499, 0.9984468]; p = 0.008) on cholecystitis. No significant causal effect of total cholesterol (TC) (OR [95% CI] = 0.9994228 [0.9994222, 0.9994233]; p = 0.296), triglycerides (OR [95% CI] = 0.9990893 [0.9990882, 0.9990903]; p = 0.238) and high-density lipoprotein (HDL) cholesterol (OR [95% CI] = 0.9997020 [0.9997017, 0.9997023]; p = 0.565) was found on cholecystitis. Conclusion: These findings suggest that LDL cholesterolhas a slight protective effect on cholecystitis, which can be easily affected by confounding factors. TC, triglycerides and HDL cholesterol don't have causal effect on cholecystitis. The protective effect of serum lipids on cholecystitis, though possible, remain less certain. [ABSTRACT FROM AUTHOR]

LuTan-1 (LT-1), i.e., TwinSAR-L, mission is an innovative spaceborne bistatic synthetic aperture radar (SAR) mission that is based on two satellites operating at L-band with flexible formation flying, which is planned to launch in 2020. The primary objective of LT-1 is to generate a highly accurate global digital elevation model (DEM). Beyond that, LT-1 will serve for the demonstration of some state-of-the-art technologies in radar field and some applications, such as biomass inversion, disaster forecasting, and climate and environmental monitoring, and phase synchronization is a technical challenge in realizing the highly accurate topography and deformation measurements. The pulsed alternate synchronization scheme, which is proposed to solve the synchronization problem of TerraSAR-X add-on for Digital Elevation Measurements (TanDEM)-X, is an efficient and accurate method. However, it interrupts the normal work of the TanDEM-X, accordingly flowing a series of problems. For LT-1, a novel synchronization scheme, in which the phase synchronization signal is exchanged by virtue of a time slot between radar signals, is applied. Thus, the working efficiency and synchronization accuracy can further be improved. Furthermore, the performance prediction and phase synchronization experiment for this synchronization scheme is presented, which verifies the feasibility of the proposed scheme. Finally, in order to guarantee the transmission quality of the synchronization signal, the illumination combinations and gain variation of the synchronization antenna in an orbital period are detailed. [ABSTRACT FROM AUTHOR]

Tin-based anode materials including oxides, composites oxides, and tin-based alloys are identified as promising candidates for energy storage attributed to the highest theoretical specific capacity. We introduce Ti3C2-MXene as structural skeletons and amorphous carbon as conductive networks for tin oxide in this work. Herein, carbon-coated kernel-like SnO2 coupling with two-dimensional (2D) layered structure Ti3C2-MXene (C@SnO2/Ti3C2) composites were prepared by a hydrothermal reaction and a further calcination process. The fabricated C@SnO2/Ti3C2 nanocomposites exhibit smaller charge transfer resistance, larger Li+ diffusion coefficient, and better cycling stability than SnO2/Ti3C2 and pure Ti3C2. Most of all, C@SnO2/Ti3C2 nanocomposites display excellent initial capacity of 1531.5 mAh g−1 at current density of 100 mA g−1 and show outstanding rate performance of 540 mAh g−1even after 200 cycles. In our work, we will provide a new research idea for the composite materials of metal oxides and two-dimensional layered materials in the field of electrode materials for batteries. [ABSTRACT FROM AUTHOR]

The rapid evolution of resistance in agricultural pest poses a serious threat to global food security. However, the mechanisms of resistance through metabolic regulation are largely unknown. Here, we found that a GST gene cluster was strongly selected in North China (NTC) population, and it was significantly genetically-linked to lambda-cyhalothrin resistance. Knockout of the GST cluster using CRISPR/Cas9 significantly increased the sensitivity of the knockout strain to lambda-cyhalothrin. Haplotype analysis revealed no non-synonymous mutations or structural variations in the GST cluster, whereas GST_119 and GST_121 were significantly overexpressed in the NTC population. Silencing of GST_119 or co-silencing of GST_119 and GST_121 with RNAi significantly increased larval sensitivity to lambda-cyhalothrin. We also identified additional GATAe transcription factor binding sites in the promoter of NTC_GST_119. Transient expression of GATAe in Hi5 cells activated NTC_GST_119 and Xinjiang (XJ)_GST_119 transcription, but the transcriptional activity of NTC_GST_119 was significantly higher than that of XJ_GST_119. These results demonstrate that variations in the regulatory region result in complex expression changes in the GST cluster, which enhances lambda-cyhalothrin resistance in field-populations. This study deepens our knowledge of the evolutionary mechanism of pest adaptation under environmental stress and provides potential targets for monitoring pest resistance and integrated management. A glutathione S-transferase gene cluster in the cotton bollworm, Helicoverpa armigera, contributes to natural insecticide resistance in this agricultural pest. [ABSTRACT FROM AUTHOR]

Simple Summary: To understand the impact of climate change on marine mammals, we focused on the spotted seal population in the North Pacific. This ice-breeding species exhibits distinct variations across different regions. Our study aimed to quantify their ecological niches and conduct a conservation gap analysis. We found clear niche divergence among three populations and observed habitat contraction driven by climate change, potentially leading to breeding habitat loss in certain areas. Unfortunately, existing marine protected areas do not adequately cover most spotted seal habitats. By incorporating local adaptation into species distribution modeling, our research provides valuable insights for designing effective conservation policies to protect the different geographical populations of spotted seals in the face of climate change. This study highlights the importance of considering local adaptation in conservation and management strategies for marine mammal species. Local adaptation has been increasingly involved in the designation of species conservation strategies to response to climate change. Marine mammals, as apex predators, are climatechange sensitive, and their spatial distribution and conservation requirements are critically significant for designing protection strategies. In this study, we focused on an ice-breeding marine mammal, the spotted seal (Phoca largha), which exhibits distinct morphological and genetic variations across its range. Our objectives were to quantify the ecological niches of three spotted seal populations, construct the species-level model and population-level models that represent different regions in the Bering population (BDPS), Okhotsk population (ODPS) and southern population (SDPS), and conduct a conservation gap analysis. Our findings unequivocally demonstrated a clear niche divergence among the three populations. We predicted habitat contraction for the BDPS and ODPS driven by climate change; in particular, the spotted seals inhabiting Liaodong Bay may face breeding habitat loss. However, most spotted seal habitats are not represented in existing marine protected areas. Drawing upon these outcomes, we propose appropriate conservation policies to effectively protect the habitat of the different geographical populations of spotted seals. Our research addresses the importance of incorporating local adaptation into species distribution modeling to inform conservation and management strategies. [ABSTRACT FROM AUTHOR]

By means of zincophilic regulation and protection of covalent organic framework (COF), uniform Zn ion deposition can be induced to inhibit dendrite growth and prevent chemical corrosion reactions. Moreover, abundant zincophilic sites and excellent zinc ion conduction pathway in the interfacial layer of COF can optimize the zinc ion transfer kinetics between electrolyte and Zn anode, thus inducing uniform Zn ion migration, nucleation, dissolution/plating. To realize the efficient and stable utilization of zinc anode. [Display omitted] Zn-ion energy storage devices will play important roles in the future energy storage field. However, Zn-ion device development suffers significantly from adverse chemical reactions (dendrite formation, corrosion, and deformation) on the Zn anode surface. Zn dendrite formation, hydrogen evolution corrosion, and deformation combine to degrade Zn-ion devices. Zincophile modulation and protection using covalent organic frameworks (COF) inhibited dendritic growth by induced uniform Zn ion deposition, which also prevented chemical corrosion. The Zn@COF anode circulated stably for more than 1800 cycles even at high current density in symmetric cells and maintained a low and stable voltage hysteresis. This work explains the surface state of the Zn anode and provides information for further research. [ABSTRACT FROM AUTHOR]

The precisely manipulated π–π stacking of the hybrid catalyst favors the specific prediction of the ORR active sites, which are the iron atoms in the form of natural Fe-N 4 that bind preferentially to the oxygen. [Display omitted] Metal macrocycles with well-defined molecular structures are ideal platforms for the in-depth study of electrochemical oxygen reduction reaction (ORR). Structural integrity of metal macrocycles is vital but remain challenging since the commonly used high-temperature pyrolysis would cause severe structure damage and unidentifiable active sites. Herein, we propose a pyrolysis-free strategy to precisely manipulate the exfoliated 2D iron polyphthalocyanine (FePPc) anchored on reduced graphene oxide (rGO) via π–π stacking using facile high-energy ball milling. A delocalized electron shift caused by π–π interaction is firstly found to be the mechanism of facilitating the remarkable ORR activity of this hybrid catalyst. The optimal FePPc@rGO-HE achieves superior half-wave potential (0.90 V) than 20 % Pt/C. This study offers a new insight in designing stable and high-performance metal macrocycle catalysts with well-defined active sites. [ABSTRACT FROM AUTHOR]

Purpose: Aerobic exercise has shown beneficial effects in the prevention and treatment of non-alcoholic fatty liver disease (NAFLD). Nevertheless, the regulatory mechanism is not turely clear. Therefore, we aim to clarify the possible mechanism by investigating the effects of aerobic exercise on NAFLD and its mitochondrial dysfunction. Methods: NAFLD rat model was established by feeding high fat diet. and used oleic acid (OA) to treat HepG2 cells. Changes in histopathology, lipid accumulation, apoptosis, body weight, and biochemical parameters were assessed. In addition, antioxidants, mitochondrial biogenesis and mitochondrial fusion and division were assessed. Results: The obtained in vivo results showed that aerobic exercise significantly improved lipid accumulation and mitochondrial dysfunction induced by HFD, activated the level of Sirtuins1 (Srit1), and weakened the acetylation and activity of dynamic-related protein 1 (Drp1). In vitro results showed that activation of Srit1 inhibited OA-induced apoptosis in HepG2 cells and alleviated OA-induced mitochondrial dysfunction by inhibiting Drp1 acetylation and reducing Drp1 expression. Conclusion: Aerobic exercise alleviates NAFLD and its mitochondrial dysfunction by activating Srit1 to regulate Drp1 acetylation. Our study clarifies the mechanism of aerobic exercise in alleviating NAFLD and its mitochondrial dysfunction and provides a new method for adjuvant treatment of NAFLD. [ABSTRACT FROM AUTHOR]

Evolution of resistance to Cry proteins in multiple pest insects has been threatening the sustainable use of Bacillus thuringiensis (Bt)‐transgenic crops. Better understanding about the mechanism of resistance to Cry proteins in insects is needed. Our preliminary study reported that the transcription of HaABCC3 was significantly decreased in a near‐isogenic line (LFC2) of a Cry1Ac‐resistant strain (LF60) of the global pest Helicoverpa armigera. However, the causality between HaABCC3 downregulation and resistance to Cry1Ac remains to be verified, and the regulatory mechanism underlying the HaABCC3 downregulation is still unclear. In this study, our data showed that both HaABCC3 and HaABCC3 downregulation were genetically linked to resistance to Cry1Ac in LF60. However, no InDels were observed in the coding sequence of HaABCC3 from LF60. Furthermore, F1 offspring from the cross of LF60 and a HaABCC2/3‐knockout mutant exhibited moderate resistance to Cry1Ac toxin; this indicated that the high resistance to Cry1Ac toxin in LF60 may have resulted from multiple genetic factors, including HaABCC2 mis‐splicing and HaABCC3 downregulation. Results from luciferase reporter assays showed that promoter activity of HaABCC3 in LF60 was significantly lower than that in the susceptible strain, which indicated that HaABCC3 downregulation was likely mediated by promoter variation. Consistently, multiple variations of the GATA‐ or FoxA‐binding sites in the promoter region of HaABCC3 were identified. Collectively, all results in this study suggested that the downregulation of HaABCC3 observed in the H. armigera LF60 strain, which is resistant to Cry1Ac, may be mediated by a cis‐regulatory mechanism. [ABSTRACT FROM AUTHOR]

Helicoverpa armigera is a polyphagous destructive lepidopteran pest with strong Bacillus thuringiensis (Bt) resistance. Cholesterol, a vital component for insect growth, can only be obtained from food, and its transfer and metabolism are regulated by sterol carrier protein-2 (SCP-2). This study examined whether H. armigera SCP-2 (HaSCP-2) gene expression, involved in cholesterol absorption, can be silenced by nanocarrier fluorescent nanoparticle-RNA interference (FNP-RNAi) by larval feeding and whether the silencing affected H. armigera development. Fluorescence microscopy showed that nanoparticle-siRNA was distributed in Ha cells and the larval midgut. FNP-HaSCP-2 siRNA suppressed HaSCP-2 expression by 52.5% in H.armigera Ha cells. FNP can effectively help deliver siRNA into cells, protect siRNA, and is not affected by serum. FNP-siRNA in vivo biological assays showed that HaSCP-2 transcript levels were inhibited by 70.19%, 68.16%, and 67.66% in 3rd, 4th, and 5th instar larvae, leading to a decrease in the cholesterol level in the larval and prepupal fatbodies. The pupation rate and adult emergence were reduced to 26.0% and 56.52%, respectively. This study demonstrated that FNP could deliver siRNA to cells and improve siRNA knockdown efficiency. HaSCP-2 knockdown by FNP-siRNA in vivo hindered H. armigera growth and development. FNP could enhance RNAi efficiency to achieve pest control by SCP-2-targeted FNP-RNAi. [ABSTRACT FROM AUTHOR]

Background: The black cutworm, Agrotis ipsilon, is a serious global underground pest. Its distinct phenotypic traits, especially its polyphagy and ability to migrate long distances, contribute to its widening distribution and increasing difficulty of control. However, knowledge about these traits is still limited. Results: We generated a high-quality chromosome-level assembly of A. ipsilon using PacBio and Hi-C technology with a contig N50 length of ~ 6.7 Mb. Comparative genomic and transcriptomic analyses showed that detoxification-associated gene families were highly expanded and induced after insects fed on specific host plants. Knockout of genes that encoded two induced ABC transporters using CRISPR/Cas9 significantly reduced larval growth rate, consistent with their contribution to host adaptation. A comparative transcriptomic analysis between tethered-flight moths and migrating moths showed expression changes in the circadian rhythm gene AiCry2 involved in sensing photoperiod variations and may receipt magnetic fields accompanied by MagR and in genes that regulate the juvenile hormone pathway and energy metabolism, all involved in migration processes. Conclusions: This study provides valuable genomic resources for elucidating the mechanisms involved in moth migration and developing innovative control strategies. [ABSTRACT FROM AUTHOR]

In the bistatic synthetic aperture radar (BiSAR) system, the unavoidable frequency deviation between the oscillators (USOs) will result in additional phase modulation in the demodulated radar signal, which significantly degrades the quality of the SAR image and digital elevation model (DEM) product. The innovative L-band spaceborne BiSAR system LuTan-1 (LT-1) employs a non-interrupted synchronization scheme to acquire the synchronization phase error. This advanced phase synchronization scheme avoids interrupting the normal BiSAR data acquisition and further increases the synchronization frequency. However, some non-ideal factors in the transmission link like attenuation, multipath effect, interference, etc., may cause the synchronization phase to be polluted by noise. A phase denoising approach based on compressive sensing (CS) is proposed to improve the accuracy of synchronization phase. The imaging phase with high signal-to-noise ratio (SNR) is input into the K-SVD algorithm to learn the prior information, and then the noise of the synchronization compensation phase is eliminated by maximum a posteriori (MAP) estimation. The data acquired from the ground validation system of the LT-1 synchronization module are adopted for the validation experiment. The proposed phase denoising method achieves higher phase synchronization accuracy compared with traditional ones. The processing results verify the effectiveness of the proposed method and demonstrate its potential for future on-orbit applications of the LT-1 mission. [ABSTRACT FROM AUTHOR]

The prevalence of low clouds significantly affects flight safety in Southwest China. However, relevant cloud parameters, especially low cloud-base height (LCBH), lack accurate forecasts. Based on the hourly atmospheric vertical profiles of ERA5 from 2008 to 2019, we developed a new algorithm for estimating LCBH by combining relative humidity (RH) threshold methods with convective condensation level (CCL) (RHs-CCL). To evaluate the performance of RHs-CCL, we use it to estimate the hourly LCBH of airports in Southwest China and compare the results with those based on the ground-based observations and the ERA5 CBH data. Using the observations as a ground truth, we compare the RHs-CCL algorithm with several existing algorithms with the following findings: 1) The correlation coefficient between RHs-CCL and observations reaches 0.5 on average, and the error of RHs-CCL is smaller than those of existing algorithms, with the minimum mean absolute error and root-mean-square error at the four airports studies being able to reach 243 and 321 m. 2) The bias score of RHs-CCL is 0.97 on average, and low clouds classification utilizing RHs-CCL attains the highest accuracy, up to 86%. 3) The errors of ERA5 CBH are the largest when compared with the others. 4) By implementing convective cloud occurrence condition and CCL, RHs-CCL has better applicability in regions of enhanced convective activity. These results suggest the potential of RHs-CCL as an algorithm moving forward for improvement of the LCBH estimates based upon high-resolution reanalysis products and for better predictions of the LCBH utilizing outputs from numerical weather prediction models. Significance Statement: The new algorithm developed in this study can accurately estimate low cloud-base heights from vertical profiles of atmospheric variables. It provides us a much more computationally efficient approach for predicting low cloud-base height relative to running cloud models, which is critical for weather forecasting at locations lacking computational resources and/or cloud modeling capability. In areas such as Southwest China, low clouds are very common, and they pose major threats to aviation safety. The new algorithm has been successfully integrated into the daily operation at Guiyang Airport in Southwest China and demonstrated excellent skills in estimating cloud-base heights. The implementation of the algorithm in aviation forecasting over a broader region is on the horizon. [ABSTRACT FROM AUTHOR]

• Dec@PLGA@aMM could enhance the tumor suppression through restoration of TSGs. • The Dec@PLGA@aMM group showed the higher CD4+ T cells and CD8+ T cells, indicating the enhanced immunotherapy. • The decitabine could enhance aPD-L1-mediated immunotherapy of HCC via epigenetic alteration. • This novel targeted PLGA NPs are aimed to treat HCC by decreasing DNA methylation and blocking PD-L1. DNA methyltransferase (DNMT) inhibitor represents the first clinical breakthrough via targeting aberrant cancer epigenomes. Demethylation drugs such as decitabine can restore tumor suppressor gene (TSG) expression and function to achieve anti-tumor effect. Despite DNMT inhibitors have shown significant efficacy for treating leukemia, their application in solid tumor such as HCC is limited due to short in vivo half-lives. In this study, the DNMT1 inhibitor decitabine was first loaded into the Polylactic-co-glycolic acid (PLGA) spherical nanoparticles (Dec@PLGA). The vesicle of PD-L1 antibody and macrophage membrane (aMM) was further coated onto the surface of Dec@PLGA to finally synthesize Dec@PLGA@aMM. Dec@PLGA@aMM was in uniformed spherical structure with hydrodynamic particle size of 95.7 ± 9.1 nm and surface zeta potential of −15.1 ± 3.3 mV. Dec@PLGA@aMM significantly increased the expression of both p14 and p16 in a concentration-dependent manner. Dec@PLGA@aMM could enhance the tumor suppression through restoration of TSGs, which were epigenetically silenced by DNA hypermethylation. The Dec@PLGA@aMM group showed significantly (P < 0.05) less tumor volume than PBS group, PLGA@MM group, aPD-L1 group, PLGA@aMM group, decitabine group, Dec + aPD-L1 group, and Dec@PLGA@MM group. The decitabine could enhance aPD-L1-mediated immunotherapy of HCC via epigenetic alteration. This novel targeted PLGA NPs are aimed to treat HCC by decreasing DNA methylation and blocking PD-L1, thus providing new ideas for effective treatments via epigenetic alteration for HCC patients clinically. [ABSTRACT FROM AUTHOR]

Insect resistance evolution poses a significant threat to the advantages of biopesticides and transgenic crops utilizing insecticidal Cry-toxins from Bacillus thuringiensis (Bt). However, there is limited research on the relationship between transcriptional regulation of specific toxin receptors in lepidopteran insects and their resistance to Bt toxins. Here, we report the positive regulatory role of the SfGATAe transcription factor on the expression of the ABCC2 gene in Spodoptera frugiperda. DNA regions in the SfABCC2 promoter that are vital for regulation by SfGATAe, utilizing DAP-seq technology and promoter deletion mapping. Through yeast one-hybrid assays, DNA pull-down experiments, and site-directed mutagenesis, we confirmed that the transcription factor SfGATAe regulates the core control site PBS2 in the ABCC2 target gene. Tissue-specific expression analysis has revealed that SfGATAe is involved in the regulation and expression of midgut cells in the fall armyworm. Silencing SfGATAe in fall armyworm larvae resulted in reduced expression of SfABCC2 and decreased sensitivity to Cry1Ac toxin. Overall, this study elucidated the regulatory mechanism of the transcription factor SfGATAe on the expression of the toxin receptor gene SfABCC2 and this transcriptional control mechanism impacts the resistance of the fall armyworm to Bt toxins. [ABSTRACT FROM AUTHOR]

Aqueous Zn-ion batteries (ZIBs) show great potential in energy storage systems because of their high theoretical capacities, high safety, low cost, and environmental friendliness. The lack of suitable cathode materials for sustaining the Zn2+ intercalation/deintercalation severely restricts their further application. Herein, calcium-intercalated birnessite MnO2 anchored on carbon nanotubes (CNTs) was designed as a cathode for ZIBs. The cathode material can be facilely produced by a simple one-pot reaction process. The external calcium-intercalated MnO2 with large layer spacing affords a fast ionic migration rate and the internal CNTs serving as a structural framework endow the electrode with better electrical conductivity. Benefiting from the larger interlayer spacing and the enhanced electrical conductivity, the CNT-CaMO cathode shows a high specific capacity of 351.8 mA h g−1 at 200 mA g−1 and a long cycle life over 6000 cycles. Besides, the H+ and Zn2+ co-intercalation storage mechanism was confirmed by ex situ XRD, SEM, and XPS analyses. This work opens up a new way to develop aqueous ZIB cathode materials with a high reversible capacity and long cycle life. [ABSTRACT FROM AUTHOR]

Graphene nanosheet and ternary-component nickel cobalt aluminum-layered double hydroxide composite (GNS/NiCoAl-LDH) has been successfully fabricated by a facile assembly method. The NiCoAl-LDH flakes homogeneously distribute on the surfaces of GNS, forming a three-dimensional nanosheets array structure. Electrochemical properties are characterized by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The influence of GNS doped content on the electrochemical behavior of GNS/NiCoAl-LDH composite has been studied. The result indicate that when the GNS content is 3.0 %, the GNS/NiCoAl-LDH composite electrode exhibits a maximum specific capacitance of 1,962 F g at 1 A g and remains at 1,180 F g even at a high current density of 10 A g. After 2,000 cycles, the composite electrode keeps a remarkable specific capacitance of 1,260 F g at 5 A g. The enhanced electrochemical performances of the composite are attributed to the highly electron conductivity and large specific surface area of the graphene nanosheets. This newly designed GNS/NiCoAl-LDH composite may offer a promising electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

This paper introduces a new design route to fabricate nickel aluminum-layered double hydroxide (NiAl-LDH) nanosheets/hollow carbon nanofibers (CNFs) composite through an in situ growth method. The NiAl-LDH thin layers which grow on hollow carbon nanofibers have an average thickness of 13.6 nm. The galvanostatic charge–discharge test of the NiAl-LDH/CNFs composite yields an impressive specific capacitance of 1613 F g −1 at 1 A g −1 in 6 M KOH solution, the composite shows a remarkable specific capacitance of 1110 F g −1 even at a high current density of 10 A g −1 . Furthermore, the composite remains a specific capacitance of 1406 F g −1 after 1000 cycles at 2 A g −1 , indicating the composite has excellent high-current capacitive behavior and good cycle stability in compared to pristine NiAl-LDH. [ABSTRACT FROM AUTHOR]

The Notch signaling pathway plays versatile roles during heart development. However, there is contradictory evidence that Notch pathway either facilitates or impairs cardiomyogenesis in vitro. In this study, we developed iPSCs by reprogramming of murine fibroblasts with GFP expression governed by Oct4 promoter, and identified an effective strategy to enhance cardiac differentiation through timely modulation of Notch signaling. The Notch inhibitor DAPT (N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester) alone drove the iPSCs to a neuronal fate. After mesoderm induction of embryoid bodies initiated by ascorbic acid (AA), the subsequent treatment of DAPT accelerated the generation of spontaneously beating cardiomyocytes. The timed synergy of AA and DAPT yielded an optimal efficiency of cardiac differentiation. Mechanistic studies showed that Notch pathway plays a biphasic role in cardiomyogenesis. It favors the early–stage cardiac differentiation, but exerts negative effects on the late-stage differentiation. Therefore, DAPT administration at the late stage enforced the inhibition of endogenous Notch activity, thereby enhancing cardiomyogenesis. In parallel, DAPT dramatically augmented the expression of Wnt3a, Wnt11, BMP2, and BMP4. In conclusion, our results highlight a practicable approach to generate cardiomyocytes from iPSCs based on the stage-specific biphasic roles of Notch signaling in cardiomyogenesis. [ABSTRACT FROM AUTHOR]

Indium hydroxide [In(OH)3] nanocubes were synthesized using a simple amino acid-assisted hydrothermal process. The wettability of the as-synthesized In(OH)3 nanocubes films is studied by measuring water contact angle (CA). The static CA for water over 150° is observed, which is closely related to both the In(OH)3 nanocubes structure and chemical modification. The photocatalytic activity of as-prepared In(OH)3 nanocubes is evaluated by testing the photodegradation of rhodamine B (RhB) dye under ultraviolet (UV) light irradiation. The degradation rate of RhB reaches 93.25% after 16 h of adding as-synthesized In(OH)3 nanocubes in RhB solution, which can be attributed to the large surface area of In(OH)3 nanocubes for helping to increase the photocatalytic reaction sites. A facile route is applied to synthesize In(OH)3 nanocubes through amino acid-assisted hydrothermal method. The water contact angle over 150° accompanying with sliding angle of 1° of the glass modified by the as-synthesized In(OH)3 nanocubes and 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The In(OH)3 nanocubes also present excellent photocatalytic degradation of rhodamine B. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the influence of cytochrome c on apoptosis induced by Anagrapha (Syngrapha) falcifera multiple nuclear polyhedrosis virus (AfMNPV). Microscopic observation revealed that infection of SL-1 cells with AfMNPV resulted in apoptosis, displaying apoptotic bodies in fluorescent-stained nuclei of AfMNPV-infected SL-1cells. Western blot analysis demonstrated that AfMNPV-induced apoptosis in insect SL-1 cells was significantly inhibited by cyclosporin A which blocked a translocation of cytochrome c from the mitochondria to the cytosol. As determined by using AC-DEVD-AFC as substrate, the activity of caspase-3 in AfMNPV-induced cells was detected as early as 4h post infection, gradually increased with time extension, and reached a highest level after 16h of infection. However, activity of caspase-3 in apoptotic cells decreased in the presence of cyclosporin A (30μM), indicating that activation of caspase-3 in SfaMNPV-induced cells was dependent on the release of cytochrome c from the mitochondria. In addition, cyclosporin A could markedly inhibit mitochondrial transmembrane potential (ΔΨm) disruption in undergoing apoptotic cells. These data indicate that cytochrome c plays a key role in AfMNPV-induced apoptosis in S. litura cells and may be required for caspase activation during the induction of apoptosis. [Copyright &y& Elsevier]

MXene is widely used as electrode materials in lithium-ion batteries due to its unique morphology, which realizes rapid ion diffusion and provides more ion insertion channels, whereas transition metal phosphides show a promising lithium storage performance in the field of energy storage due to their high theoretical capacity. In the present paper, cobalt phosphide nanoparticles (NPs) were self-grown on Ti 3 C 2 sheets via a low-temperature phosphating method, which showed good cycle stability as the anode in lithium-ion batteries (LIBs). After 1000 cycles, the specific capacity was maintained at 650 mAh g−1 with a high coulombic efficiency (98.8%) at 700 mA g−1, which was approximately 4 and 6 times higher than that of pristine CoP–Co 2 P and pure Ti 3 C 2 , respectively. The enhanced electrochemical performance was attributed to the large specific surface (61.2 m2 g−1), which offered sufficient active sites for the electrochemical reaction. Also, the outstanding redox reaction activity of cobalt phosphide effectively improved the electrochemical reaction efficiency during the charge-discharge process. The strategy proposed in this study could be extended to other two dimensional (2D) materials to achieve their full potential. Image 1 • CoP–Co 2 P are self-grown on Ti 3 C 2 via a low-temperature phosphorization method. • CoP–Co 2 P were uniformly distributed among interlamination spaces of Ti 3 C 2 sheet. • CoP–Co 2 P/Ti 3 C 2 shows excellent lithium storage performance and reversibility. • The electrochemical reaction mechanism of CoP–Co 2 P/Ti 3 C 2 was discussed in detail. • The strategy can be extended to other 2D materials to achieve their potential. [ABSTRACT FROM AUTHOR]

Bifunctional catalyst was prepared by one-step pyrolysis of trimetallic ZIF. The obtained catalyst showed excellent charge–discharge stability in rechargeable Zn-air battery. • A facile and effect strategy is proposed for the synthesis of catalyst precursor. • This strategy reduces the adverse effects of the pyrolysis process on the catalyst. • The coexistence of Co NPs and CoFe-N x improves the ORR/OER activity. • The catalyst displays excellent durability as a cathode for Zn-air battery. Searching for high active, low cost and durable catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) remains challenge in developing metal-air battery cathodes. Herein, we proposed a novel bifunctional catalyst derived from the pyrolysis of Co/Fe/Zn trimetallic zeolitic imidazolite framework. The obtained Co@CoFe 0.01 N C catalyst displays desirable activity for both ORR and OER (E 1/2 = 0.844 V, E j=10 = 1.654 V). The Zn-air battery equipped with Co@CoFe 0.01 N C catalyst on the cathode exhibits a high peak power density of 174.1 mW cm−2, which is much superior than that of commercial 20% Pt/C (87.6 mW cm−2). Significantly, the designed Co@CoFe 0.01 N C presents an outstanding stability for over 100 h in rechargeable Zn-air battery. [ABSTRACT FROM AUTHOR]

Sluggish oxygen reduction reaction (ORR) kinetics is the biggest obstacle in the development of metal air batteries. High-efficiency ORR catalysts with low cost are in urgent needs. Herein, we propose a robust Fe–N–C ORR catalyst with highly dispersed Fe-N x active sites on graphitic-N dominated porous carbon. The synchrotron radiation analyses reveal the discrete Fe-N x coordination derived from the Prussian blue (PB) while the graphitic-N doped porous carbon formed by pyrolysis of the polyaniline (PANI). In virtue of their synergistic catalysis, the tailored Fe–N–C catalyst shows a comparable catalytic activity and a better methanol-tolerance than the commercial Pt/C catalyst. The assembled Zn-Air battery demonstrates a specific capacity of 783 mAh g−1 as well as energy density of 917 Wh kg−1 at 10 mA cm−2, and a maximum power density of 112 mW cm−2 at 191 mA cm−2. A robust Fe– N –C ORR catalyst derived from PB-anchored PANI with well-dispersed Fe-N x active sites on graphitic-N dominated porous carbon host shows comparable performance to the commercial Pt/C catalyst. Image 1 [ABSTRACT FROM AUTHOR]

The deviation between the two oscillators in BiSAR systems will cause a residual modulation of echo signal. Therefore, the phase synchronization is an important issue that must be addressed for BiSAR systems. An advanced non-interrupted phase synchronization scheme is used for the LuTan-1 SAR satellite. The synchronization transceiver (STR) is designed for transmitting and receiving synchronization signals. In addition, STR mainly consists of master and auxiliary transceivers and switch module. Furthermore, the function and working principle of STR are introduced, and the detailed design of each part is described. The measured results are also evaluated to prove the performance of the STR. In addition, the phase synchronization accuracy is also demonstrated to verify the effectiveness of the non-interrupted synchronization scheme. The standard deviation (STD) of the residual phase is less than 0.3 degrees. The results have guiding significance for the synchronization unit design of LuTan-1 and the future BiSAR system. [ABSTRACT FROM AUTHOR]

Background: Previous studies on the pneumonia outbreak caused by the 2019 novel coronavirus disease (COVID-19) were mainly based on information from adult populations. Limited data are available for children with COVID-19, especially for infected infants.Methods: We report a 55-day-old case with COVID-19 confirmed in China and describe the identification, diagnosis, clinical course, and treatment of the patient, including the disease progression from day 7 to day 11 of illness.Results: This case highlights that children with COVID-19 can also present with multiple organ damage and rapid disease changes.Conclusions: When managing such infant patients with COVID-19, frequent and careful clinical monitoring is essential. [ABSTRACT FROM AUTHOR]

Digital beamforming (DBF) with Scan-On-Receive (SCORE) in elevation is a powerful technique for spaceborne synthetic aperture radar (SAR) to achieve high-resolution wide-swath (HRWS) images. DBF in spaceborne SAR should be implemented in real-time to reduce the volume of the downloaded data. Current digital beamformers in SAR systems usually use phase shift instead of a time delay network to ensure real-time implementation. However, conventional phase shift DBF SAR with narrow array bandwidth is not applicable for broadband signals. The beam steering deviation as a function of frequency is obvious for signals with large fractional bandwidth, which appears as a phenomenon of frequency dispersion. If the signal bandwidth is wider than the array bandwidth, frequency dispersion can significantly deteriorate the signal-to-noise ratio (SNR) and must be well relieved. This article analyzes the frequency dispersion in DBF SAR and proposes an innovative DBF-SCORE scheme with specially designed scalloped beam. The proposed digital scalloped beamforming (DSBF) scheme is effective in relieving the influence of frequency dispersion in DBF SAR. Theoretical analysis and simulation results validate the effectiveness of the proposed scheme. The proposed DSBF scheme gives practical solution to the problem of frequency dispersion in broadband DBF SAR, which makes DBF-SCORE a more practical technique for future spaceborne HRWS SAR. [ABSTRACT FROM AUTHOR]

LuTan-1 (LT-1) refers to an innovative mission of spaceborne bistatic synthetic aperture radar (BiSAR) adopting the phase synchronization scheme of pulse exchange, which is scheduled to be launched in 2020. In this mission, the multipath effect caused by the reflection of satellites and Doppler frequency shift resulting from the relative motion between satellites constitute two critically latent factors deteriorating the performance of the phase synchronization scheme. This article details a loss factor to evaluate the fading of synchronization signals under the reflection of smooth and rough surfaces and estimates the influence of Doppler frequency shift on synchronization signals. Furthermore, the multipath channel impulse response is modeled, and the correlation characteristics of multipath channel are described by the coherent bandwidth and coherent time. In addition, two simulation experiments based on the system parameters of LT-1, are implemented to assess the influence of time-invariant and -varying multipath effects on the phase synchronization scheme. A scale experiment is also executed to quantify the influence of multipath effect on phase synchronization, and its result demonstrates that the phase synchronization scheme of LT-1 can not only achieve full coverage of space and backup capability of pulse exchange but also meet the application requirements under multipath effect. [ABSTRACT FROM AUTHOR]

Exploring efficient and durable non-precious metal catalysts for oxygen reduction reaction (ORR) has long been pursued in the field of metal-air batteries, fuel cells, and solar cells. Rational design and controllable synthesis of desirable catalysts are still a great challenge. In this work, a novel approach is developed to tune the morphologies and structures of Fe–N–C catalysts in combination with the dual nitrogen-containing carbon precursors and the gas-foaming agent. The tailored Fe–N 1 /N 2 –C-A catalyst presents gauze-like porous nanosheets with uniformly dispersed tiny nanoparticles. Such architectures exhibit abundant Fe-N x active sites and high-exposure surfaces. The Fe–N 1 /N 2 –C-A catalyst shows extremely high half-wave potential (E 1/2 , 0.916 V vs. RHE) and large limiting current density (6.3 mA cm−2), far beyond 20 wt% Pt/C catalyst for ORR. This work provides a facile morphological and structural regulation to increase the number and exposure of Fe-N x active sites. The tailored Fe–N–C catalyst presents plentiful Fe-N x active sites and highly exposed active surfaces, resulting in an ultra-high ORR activity far beyond the 20 wt% Pt/C catalyst. Image 1 • A novel approach is explored to tune morphology and structure of Fe–N–C catalyst. • The tailored catalyst presents abundant active sites and high exposure surfaces. • The catalyst shows ultrahigh ORR activity, far beyond the commercial Pt/C. [ABSTRACT FROM AUTHOR]

LuTan-1 [(LT-1), i.e., TwinSAR-L] mission is an innovative spaceborne bistatic synthetic-aperture radar (BiSAR) mission focusing mainly on differential interferometry, which will be launched in 2020. This article introduces some important aspects of the LT-1 mission for the first time, including the formation configuration, imaging mode, application scenarios, and the efficient baselines between the master satellite and the slave satellite. To realize the high accurate topography and deformation measurements, a wide swath BiSAR focusing algorithm with phase reserving ability should be developed. This article proposes a modified bistatic range-Doppler algorithm based on 2-D principle of stationary phase spectrum, which reduces the phase error introduced by the root term expansion and has an excellent focus performance and a good phase reserving ability. Finally, the spaceborne bistatic simulation experiments using orbital parameters and imaging mode of the LT-1 mission, including point targets and scene targets, are utilized to illustrate the validity and accuracy of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Development of fuel cells is greatly hindered by their sluggish oxygen reduction reaction (ORR). Therefore, rational design and cost‐effective fabrication of ORR catalysts with high activity and durability are of paramount importance to the commercialization of fuel cells. In this work, we develop one‐step synthesis of nitrogen‐doped Fe/Fe3C‐encapsulated graphitic layers/carbon nanotubes (Fe/Fe3C@NGL‐NCNT) for ORR. The interpenetration of the two‐dimensional (2D) NGL and the one‐dimensional (1D) NCNT conduces to the construction of three‐dimensional (3D) network structure. Such heterostructure renders Fe/Fe3C@NGL‐NCNT with different catalytically active sites and improved mass transfer. Fuethermore, the inimitable NCNT with winding earthworm‐like structure and a small diameter of below 10 nm provides plentiful active defect sites. Consequently, the synergistic effect of unique 1D/2D/3D heterostructure endows Fe/Fe3C@NGL‐NCNT catalyst with a superior activity and durability compared to commercial Pt/C catalyst. This work provides worthy inspiration for engineering excellent ORR electrocatalysts by integrating 1D/2D/3D materials with different catalytically active conponents into one heterostructure via in situ synthesis. [ABSTRACT FROM AUTHOR]