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A protocol for high intermediate precision Sm isotope measurements.

There are many commercially available glycogen particles in the market due to their bioactive functions as food additive, drug carrier and natural moisturizer, etc. It would be beneficial to rapidly determine the origins of commercially-available glycogen particles, which could facilitate the establishment of quality control methodology for glycogen-containing products. With its non-destructive, label-free and low-cost features, surface enhanced Raman spectroscopy (SERS) is an attractive technique with high potential to discriminate chemical compounds in a rapid mode. In this study, we applied the combination of SERS technique and machine leaning algorithms on glycogen analysis, which successfully predicted the origins of glycogen particles from a variety of organisms with convolutional neural network (CNN) algorithm plus attention mechanism having the best computational performance (5-fold cross validation accuracy = 96.97 %). In sum, this is the first study focusing on the discrimination of commercial glycogen particles originated from different organisms, which holds the application potential in quality control of glycogen-containing products.

BACKGROUND: SQUAMOSA promoter binding protein-like (SPL) proteins are a class of plant-specific transcription factors that play important roles in plant development. However, the majority of SPL genes in strawberry are functionally uncharacterized. OBJECTIVE: To understand the biological functions and elucidate the molecular regulatory mechanisms of SPL genes in strawberry development. METHODS: The FvSPL1 gene from woodland strawberry was cloned and the phylogenetic tree was analyzed using bioinformatics methods. Subcellular localization, transcriptional activity, DNA binding ability and regulatory mechanisms of FvSPL1 were analyzed through biochemical and genetic approaches. RESULTS: Phylogenetic analysis with SPL genes from Arabidopsis, tomato and chrysanthemum indicated that FvSPL1 clustered in the same group as those of the miR156 target site located at the 3′-untranslated region. Further biochemical analysis indicated that FvSPL1 was exclusively localized in the nucleus. Electrophoretic mobility shift assay demonstrated that FvSPL1 could specifically recognize the GTAC motif. Transcriptional activity analysis showed that FvSPL1 is a transcriptional activator that could activate the expression of the FvAP1 gene. Finally, transgenic Arabidopsis overexpressing the FvSPL1 gene exhibited significantly early flowering. Taken together, our study indicated that FvSPL1, similar to its orthologs in Arabidopsis, mainly functions in regulating plant flowering. CONCLUSIONS: These findings provide insight into the mechanism of flowering in strawberry, and contribute to the understanding of strawberry flowering time manipulation which will facilitate the molecular breeding of strawberries.

ObjectiveTo systematically compare the bowel cleaning ability, patient tolerance and safety of oral sodium phosphate tablets (NaPTab) and oral polyethylene glycol electrolyte lavage solution (PEGL) to inform clinical decision making.MethodsPubMed, Embase, CBM, WanFang Data, CNKI, and VIP databases were searched for studies that used randomized controlled trials (RCTs) to compare the roles of NaPTab and PEGL in bowel preparation before colonoscopy. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias in the included papers. A meta-analysis was performed using RevMan 5.3 software.ResultsA total of 13 RCTs were eligible for inclusion, including 2,773 patients (1,378 and 1,395 cases in the NaPTab and PEGL groups, respectively). Meta-analysis revealed no significant difference in the cleansing quality of the NaPTab and PEGL groups [RR 1.02, 95% CI (0.96–1.08), P = 0.46]. The incidence of nausea was lower in the NaPTab group than in the PEGL group [RR 0.67, 95% CI (0.58–0.76), p < 0.00001]. Patients rated the taste of NaPTab higher than PEGL [RR 1.33, 95% CI (1.26–1.40), P < 0.00001]. Willingness to repeat the treatment was also higher in the NaPTab group than in the PEGL group [RR 1.52, 95% CI (1.28–1.80), P < 0.00001]. Both serum potassium and serum calcium decreased in both groups after the preparation; however, meta-analysis revealed that both minerals decreased more in the NaPTab group than in the PEGL group [MD = 0.38, 95% CI (0.13–0.62), P = 0.006 for serum potassium and MD = 0.41, 95% CI (0.04–0.77), P = 0.03 for serum calcium]. Meanwhile, serum phosphorus increased in both groups after the preparation; however, levels increased more in the NaPTab group than in the PEGL group [MD 4.51, (95% CI 2.9–6.11), P < 0.00001].ConclusionsWhile NaP tablets and PEGL were shown to have a similar cleaning effect before colonoscopy, NaP tablets had improved patient tolerance. However, NaP tablets had a strong effect on serum potassium, calcium, and phosphorus levels. For patients with low potassium, low calcium, and renal insufficiency, NaP tablets should be prescribed with caution. For those at high-risk for acute phosphate nephropathy, NaP tablets should be avoided. Given the low number and quality of included studies, these conclusions will require additional verification by large high-quality studies.Systematic review registration10.37766/inplasy2023.5.0013, identifier: NPLASY202350013.

A TODGA resin column was used to isolate Ba, La, Ce, Pr and Nd from geological samples.

Objective To elucidate the ameliorative effect of AP39 on myocardial fibrosis in uremic rats and investigate its possible mechanism. Methods Forty SD male rats were randomly and equally divided into 4 groups: Sham group, uremic cardiomyopathy group (UCM group), AP39 intervention group (UCM+AP39 group) and AP39 control group (n=10). The rats in the UCM group and the UCM+AP39 group were treated with classical operation of 5/6 nephrectomy to establish the uremic cardiomyopathy model, and then the rats in the latter 2 groups were given intraperitoneal injection of AP39 (100 nmol/kg, once a day) for 4 weeks, while those of the Sham and model groups were intraperitoneally injected with the same amount of normal saline. Ultrasonic imaging platform was used to detect the value of left ventricular fractional shortening (LVFS) of rats in each group. Masson staining and immunohistochemical staining were performed respectively to observe collagen deposition and the expression of Collagen Ⅲ protein in the myocardial interstitial tissue of each group. Western blotting was adopted to determine the expression levels of PETN-induced putative kinase-1 (PINK1), Parkinson's disease protein (Parkin), autophagy-related gene-5 (Atg5), microtubule-associated protein-1 light chain-3 Ⅱ/Ⅰ(LCEⅡ/Ⅰ), Beclin1 and P62 (also called sequestosome, SQSTM1) in the myocardial tissue of each group. Results As compared with those in the Sham group, the rats in the UCM group had significantly decreased LVFS, increased collagen deposition content and Collagen Ⅲ protein level (P < 0.05), and disordered arrangement in myocardial tissue. The expression levels of PINK1, Parkin, Atg5, LC3Ⅱ/Ⅰand Beclin1 were significantly reduced, while the level of P62 was enhanced in the UCM group (P < 0.05). By contrast, the rats in the UCM+AP39 group had higher LVFS, lower collagen deposition content and Collagen Ⅲ protein level than those in the UCM group (P < 0.05), the expression levels of PINK1, Parkin, Atg5, LC3 Ⅱ/Ⅰ and Beclin1 were remarkably up-regulated, and the level of P62 down-regulated (P < 0.05). Conclusion AP39 can improve uremic myocardial fibrosis in rats, which may be related to the up-regulation of PINK1/Parkin-mediated mitophagy.

A modular converter, due to its standardized product cycle, has the advantage of a low design, manufacturing, installation, and maintenance cost. In this article, a reconfigurable bidirectional fully modular converter using switched-capacitor (SC) modules is proposed. The change in the power rating and voltage gain of the converter is achievable with the change in the number and configuration of modules. A guideline of choosing the module topology is proposed to let SC modules be freely assembled to achieve different structures. To achieve modular converters with the minimized number of modules, a triangle configuration is presented. In this configuration, the number of parallel modules is adapted to the input current. In this way, the number of modules can be reduced at a high-voltage low-current stage. Experimental results verify that good current-sharing performance of the parallel SC modules in different configurations and operation modes is achievable. Experimental results also indicate that module paralleling (in these converters) could improve the power conversion efficiency of the individual module.

Background Mulberry leaf as a traditional Chinese medicine is able to treat obesity, diabetes, and dyslipidemia. It is well known that diabetes leads to intestinal microbiota dysbiosis. It is also recently discovered that liver glycogen structure is impaired in diabetic animals. Since mulberry leaves are able to improve the diabetic conditions through reducing blood glucose level, it would be interesting to investigate whether they have any positive effects on intestinal microbiota and liver glycogen structure. Methods In this study, we first determined the bioactive components of ethanol extract of mulberry leaves via high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). Murine animal models were divided into three groups, normal Sprague-Dawley (SD) rats, high-fat diet (HFD) and streptozotocin (STZ) induced type 2 diabetic rats, and HFD/STZ-induced rats administered with ethanol extract of mulberry leaves (200 mg/kg/day). Composition of intestinal microbiota was analyzed via metagenomics by sequencing the V3-V4 region of 16S rDNAs. Liver glycogen structure was characterized through size exclusion chromatography (SEC). Both Student’s t-test and Tukey’s test were used for statistical analysis. Results A group of type 2 diabetic rat models were successfully established. Intestinal microbiota analysis showed that ethanol extract of mulberry leaves could partially change intestinal microbiota back to normal conditions. In addition, liver glycogen was restored from fragile state to stable state through administration of ethanol extract of mulberry leaves. Conclusions This study confirms that the ethanol extract of mulberry leaves (MLE) ameliorates intestinal microbiota dysbiosis and strengthens liver glycogen fragility in diabetic rats. These finding can be helpful in discovering the novel therapeutic targets with the help of further investigations.

Removing interferences such as Ce on Nd isotopes during column chemistry is hard to achieve due to their similar properties. In this study, we established a simple but efficient Nd separation technique with the perfect separation of Nd from Ce and nearly 100% Nd yield using the TODGA resin (50–100 μm, Eichrom, USA) after actual measurements. All samples used here through the Nd separation technique have Ce/Nd ratios less than 0.003. The whole procedure takes about 10 h. The stable Nd isotopes were measured by MC-ICP-MS and calibrated with standard-sample-standard bracketing (SSB) combined Eu internal normalization. The potential influences of Eu and Ce on stable Nd isotopic analysis were strictly evaluated. The long-term analyses of the JNdi-1 standard produced a total average δ142/144Nd of 0.000 ± 0.029‰ (2SD, n = 210), δ145/144Nd of 0.000 ± 0.029‰ (2SD, n = 210), and δ146/144Nd of 0.000 ± 0.027‰ (2SD, n = 210). Two pure Nd standards, La Jolla and Nd-GIG, produced δ146/144Nd values (means ± 2SD, n = 20) of −0.227 ± 0.030‰ and 0.226 ± 0.021‰, respectively. δ146/144Nd (means ± 2SD, n = 20) of seven geological reference materials (BCR-1, BHVO-2, AGV-2, GSP-2, NOD-P-1, NOD-A-1, and GBW07249) were also reported. The reproducibility of δ146/144Nd was better than 0.030‰. These results are in good agreement with the published DS-TIMS methods. In addition, our method also allows the concurrent determination of the radiogenic 143Nd/144Nd ratio. All the 143Nd/144Nd ratios of these samples are identical with the preferred values published in the GeoReM Database. These results indicated that the method of Nd isotopic analysis established here can simultaneously measure high-precision δ142/144Nd, δ145/144Nd, δ146/144Nd, and radiogenic 143Nd/144Nd ratio for geological materials.

The contamination of arsenic (As) in paddy soils is one of the most critical issues in China, and subsequently threatening food safety and human health. Previous studies suggest that the transformation of As species in paddy soil is a key factor determining its availability, uptake and accumulation in crops, particularly rice grains; arsenite As(III) is more toxic and mobile than arsenate As(V). Being important components in soils, evidence shows that redox-active iron minerals play an important role in the transformation and fate of As in the rhizosphere zone in paddy soils, however, the underlying mechanisms are largely unknown. To address the above mentioned scientific questions, in this work, a simulated rhizosphere reaction system in paddy soil was built to investigate the reaction process of As(III) on the surface of goethite with and without the addition of Fe(II) under different oxic conditions (e.g., the effects of Fe(II) concentration and goethite dosages), and the transformation of As(III) to As(V) was monitored and compared in systems. Furthermore, the possible reactive oxygen species (ROSs) were identified by quenching experiments and electron spin resonance (ESR). Together with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), the mechanism of As(III) oxidation on the surface of goethite mediated by Fe(II) under oxic conditions were proposed. Our results indicate that both Fe(II) concentration and goethite dosage determine the As(III) oxidation; the presence of goethite significantly enhances the oxidation extent of As(III) from 12% (without goethite) to 18% (1.5 g/L goethite). Despite both homogenous and heterogeneous reactions of As(III) oxidation occur, results suggest that the oxidation reaction of As(III) on the surface of goethite predominates due to the rapid adsorption of As(III) onto the goethite within seconds. The increase of goethite dosage leads to a higher oxidation extent of As(III), which is likely caused by the presence of higher oxygen vacancies on goethite. Moreover, the increase of Fe(II) concentration from 5 to 15 mg/L significantly enhances the As(III) oxidation extents from ~10% to ~25% (the As(III) and Fe(II) initial concentrations are 10 and 15 mg/L), while the adsorption of total As is insignificantly affected by the concentration of Fe(II). Quenching experiments indicates that the · O2− species are the dominant ROSs determining the As(III) oxidation, which has also been confirmed by the ESR spectra. Besides, the generated As(V) mainly adsorbs on or incorporates in goethite. In conclusion, our findings suggest that the Fe(II) adsorbed on the goethite can directly activate oxygen to generate reactive oxygen species and then promote the oxidation of As(III) under oxic conditions. Importantly, the oxygen vacancies on goethite can further accelerate the oxidation of As(III) by enhancing the iron cycling and the decomposition of H2O2 to · O2− species. The findings of this study provide new insight into understanding the reaction process of As(III) near the rhizosphere zone and can be useful for developing new techniques for regulating the As contamination in paddy soils.

Diabetes is a chronic endocrine metabolism disorder that leads to hyperglycaemia. As the most common diabetic type, type 2 diabetes mellitus accounts for 90% of all diabetic disease with a key feature of insulin resistance. Mulberry leaves are commonly used in traditional Chinese medicine, and many studies confirm that mulberry leaves have positive effects on alleviating the pathological conditions of type 2 diabetes. However, its anti-diabetic effects and active ingredients are not completely understood. Compared with time- and cost-consuming experiments, network pharmacology provided a convenient method to systematically investigate the interactions between compounds in mulberry leaves and diabetes-related genes. Although similar network pharmacological studies were performed for mulberry leaves, only compounds sourced from public database or volatile components in the mulberry leaves were examined. In this study, we initially analysed the bioactive compounds from ethanol extract of mulberry leaves via liquid chromatography coupled with mass spectrometry, which generated a total of 248 components. A total of 14 active components and 49 potentially functional compounds were identified from TCMSP and PharmMapper database, respectively, which worked on 37 target proteins directly involved in the pathogenesis of T2DM. Kaempferol was shown to be the most influential active compound while androgen receptor was most widely regulated by compounds in the ethanol extract of mulberry leaves. Moreover, protein–protein interaction and target-pathway network analysis revealed that AKT1 was most important in the 37 target proteins in terms of its functions in different pathways and interactions with other target proteins. Moreover, pathway analysis showed that ethanol extract of mulberry leaves alleviated type 2 diabetes mellitus through pathways such as TNF signaling pathway, NF-κB signaling pathway, and insulin resistance pathway. In sum, this study provided a complete overview of the working mechanisms for the ethanol extract of mulberry leaves, the results of which could be used as a practical guidance for further experimental investigation of the functions of mulberry leaves during the treatment of type 2 diabetes mellitus.

Nanoscale zero-valent iron (nZVI) shows excellent reduction of Cr(Ⅵ), but the passivation on its outer surface can restrict its longevity and performance. To tackle this problem, this work introduced

According to the sit-and-wait hypothesis, long-term environmental survival is positively correlated with increased bacterial pathogenicity because high durability reduces the dependence of transmission on host mobility. Many indirectly transmitted bacterial pathogens, such as Mycobacterium tuberculosis and Burkhoderia pseudomallei, have high durability in the external environment and are highly virulent. It is possible that abiotic stresses may activate certain pathways or the expressions of certain genes, which might contribute to bacterial durability and virulence, synergistically. Therefore, exploring how bacterial phenotypes change in response to environmental stresses is important for understanding their potentials in host infections. In this study, we investigated the effects of different concentrations of salt (sodium chloride, NaCl), on survival ability, phenotypes associated with virulence, and energy metabolism of the lab strain Escherichia coli BW25113. In particular, we investigated how NaCl concentrations influenced growth patterns, biofilm formation, oxidative stress resistance, and motile ability. In terms of energy metabolism that is central to bacterial survival, glucose consumption, glycogen accumulation, and trehalose content were measured in order to understand their roles in dealing with the fluctuation of osmolarity. According to the results, trehalose is preferred than glycogen at high NaCl concentration. In order to dissect the molecular mechanisms of NaCl effects on trehalose metabolism, we further checked how the impairment of trehalose synthesis pathway (otsBA operon) via single-gene mutants influenced E. coli durability and virulence under salt stress. After that, we compared the transcriptomes of E. coli cultured at different NaCl concentrations, through which differentially expressed genes (DEGs) and differential pathways with statistical significance were identified, which provided molecular insights into E. coli responses to NaCl concentrations. In sum, this study explored the in vitro effects of NaCl concentrations on E. coli from a variety of aspects and aimed to facilitate our understanding of bacterial physiological changes under salt stress, which might help clarify the linkages between bacterial durability and virulence outside hosts under environmental stresses.

According to the sit-and-wait hypothesis, long-term environmental survival is positively correlated with increased bacterial pathogenicity because high durability reduces the dependence of transmission on host mobility. Many indirectly transmitted bacterial pathogens, such as Mycobacterium tuberculosis and Burkhoderia pseudomallei, have high durability in the external environment and are highly virulent. It is possible that abiotic stresses may activate certain pathways or the expressions of certain genes, which might contribute to bacterial durability and virulence, synergistically. Therefore, exploring how bacterial phenotypes change in response to environmental stresses is important for understanding their potentials in host infections. In this study, we investigated the effects of different concentrations of salt (sodium chloride, NaCl), on survival ability, phenotypes associated with virulence, and energy metabolism of the lab strain Escherichia coli BW25113. In particular, we investigated how NaCl concentrations influenced growth patterns, biofilm formation, oxidative stress resistance, and motile ability. In terms of energy metabolism that is central to bacterial survival, glucose consumption, glycogen accumulation, and trehalose content were measured in order to understand their roles in dealing with the fluctuation of osmolarity. According to the results, trehalose is preferred than glycogen at high NaCl concentration. In order to dissect the molecular mechanisms of NaCl effects on trehalose metabolism, we further checked how the impairment of trehalose synthesis pathway (otsBA operon) via single-gene mutants influenced E. coli durability and virulence under salt stress. After that, we compared the transcriptomes of E. coli cultured at different NaCl concentrations, through which differentially expressed genes (DEGs) and differential pathways with statistical significance were identified, which provided molecular insights into E. coli responses to NaCl concentrations. In sum, this study explored the in vitro effects of NaCl concentrations on E. coli from a variety of aspects and aimed to facilitate our understanding of bacterial physiological changes under salt stress, which might help clarify the linkages between bacterial durability and virulence outside hosts under environmental stresses.

The electricity consumption by is continuously increasing with the development of internet technologies. Improving the power supplies efficiency of datacenter is critical for energy saving. Synchronous buck converter is widely used in datacenter as well as other applications. A method of increasing the efficiency for synchronous buck converter is add an extra auxiliary circuit to make the switches in synchronous buck converter be soft switching (i.e. ZCS, ZVS). This paper presents a simple auxiliary circuit composed of one inductor, one active switch, and two Schottky diodes for synchronous buck converter to achieve the high-side and the low-side switches be ZVS turning on and ZCS turning off. Besides, the switches in the auxiliary circuit are also soft switched. The auxiliary circuit could recycle the energy stored in the output capacitor of the high-side and low-side switches. A 48 V/12 V 100 kHz synchronous buck converter with the proposed auxiliary circuit is simulated. The simulation results show that the switches in the synchronous buck converter is soft switched. The auxiliary circuit improve the synchronous buck converter’s efficiency in the whole load range, especially for the light load range, the efficiency improvement as high as 3%.

The trend of power supplies is toward high efficiency and high power density. Switched-capacitor (SC) converter is a good candidate for such trend and attract much attentions in recently years. Therefore, this paper proposes a ZVS soft-charging SC converter for higher efficiency and it is achieved by an auxiliary converter integrated in the converter. The auxiliary converter improves the SC converter’s efficiency by stores and recycle the energy produced by the voltage difference in charging and discharging state, as the SC converter without soft charging technique dissipate it as hot. Moreover, the auxiliary converter shapes the charging discharging current waveforms of the flying capacitor, which is beneficial for reducing the conduction losses on the switches. Besides, the auxiliary converter is inherent ZVS turned on the switches of the SC converter. Simulation circuit and experimental prototype with 12 V input 6 V 6 A output 100 kHz switching frequency is built to verify the proposed converters performance. The simulation and experimental results show that the proposed converter is feasibility, and the proposed converter has higher efficiency in all the load range, and the highest efficiency is as high as 98.83%.

Diurnal alteration of glycogen molecular structure has been identified in healthy mice. Recently, both fragile (disintegration in dimethyl sulfoxide) and stable (not disintegrating in DMSO) glycogen particles were found in Escherichia coli. However, how glycogen structure changes dynamically in E. coli is not clear. The question examined here is whether fragile, stable glycogen α particles occur in bacteria, following a similar pattern as in mice. In this study, we examine the dynamic changes of glycogen molecular structure over 24-h in E. coli BL21(DE3), using transmission electron microscopy, size exclusion chromatography and fluorophore-assisted carbohydrate electrophoresis at representative time points. It was found that glycogen structure was mainly fragile at the synthesis stage and largely stable during the degradation stage. qRT-PCR results indicated that balance of anabolic and catabolic gene expression levels in glycogen metabolism could be a key factor affecting the fragility of glycogen α particles in bacteria.

In this paper, fluent software was used to simulate and analyze the influence of three typical ventilation modes on the concentration distribution of fine particulate matter in human respiratory area. A sitting man with breathing was incorporated into the model, and eleven areas of 0.15 * 0.15 m2 were set up to monitor the distribution of fine particulate matter in the respiratory area. The results showed that compared with System 2 (top supply and top exhaust) and System 3 (bottom supply and upper exhaust), the mean mass concentration of fine particles in System 1 (upper supply and bottom exhaust) in the respiratory area was the highest and the maximum value appeared in the respiratory plane at 0.03 m below the nose.

High-step-up dc/dc converters are widely required in grid-connected applications with renewable energy sources. An extremely high-ratio step-up nonisolated dc/dc converter, in the form of a harmonics-boosted resonant converter, is proposed in this paper. This proposed converter consists of a high-frequency dc/ac inverter stage that is followed by a passive ac/dc rectifier stage connected in cascade. Conventionally, such a dc/ac inverter is designed to output a pure sinusoidal ac voltage with an amplitude several times the amplitude of the input voltage. However, for the proposed converter, the harmonics-boosted inverter stage is designed to contain selected voltage harmonics that significantly boost the amplitude of its output voltage. This greatly increases the overall gain of the converter. The adopted ac/dc stage is a diode-capacitor rectifier, which is of high efficiency and easily extendable to increase the voltage gain. Importantly, the proposed converter involves only one active switch. With only one active switch, the driver's loss is minimized and the converter's control is simplified. Zero-voltage switching is applied to reduce the switching loss, which also allows the converter to operate efficiently at high frequency, and thus can be designed for high power density. The optimal design of the two converter stages and their combined voltage gain is investigated and reported. Besides, a design guideline of the proposed converter is provided. A prototype of a 57-time harmonics-boosted resonant converter with 3.3 V input voltage, 500 kHz switching frequency, and 21 W output power, is built. The experimental result shows that the achieved converter's efficiency is as high as 88.6%.

Establishment of symbiosis between legumes and nitrogen-fixing rhizobia depends on bacterial Nod factors (NFs) that trigger symbiosis-related NF signaling in host plants. NFs are modified oligosaccharides of chitin with a fatty acid moiety. NFs can be cleaved and inactivated by host enzymes, such as MtNFH1 (MEDICAGO TRUNCATULA NOD FACTOR HYDROLASE 1). In contrast to related chitinases, MtNFH1 hydrolyzes neither chitin nor chitin fragments, indicating a high cleavage preference for NFs. Here, we provide evidence for a role of MtNFH1 in the symbiosis with Sinorhizobium meliloti. Upon rhizobial inoculation, MtNFH1 accumulated at the curled tip of root hairs, in the so-called infection chamber. Mutant analysis revealed that lack of MtNFH1 delayed rhizobial root hair infection, suggesting that excess amounts of NFs negatively affect the initiation of infection threads. MtNFH1 deficiency resulted in nodule hypertrophy and abnormal nodule branching of young nodules. Nodule branching was also stimulated in plants expressing MtNFH1 driven by a tandem CaMV 35S promoter and plants inoculated by a NF-overproducing S. meliloti strain. We suggest that fine-tuning of NF levels by MtNFH1 is necessary for optimal root hair infection as well as for NF-regulated growth of mature nodules.

In this paper, we propose GSTS–Uzawa method for solving a class of complex singular saddle point problems based on generalized skew-Hermitian triangular splitting (GSTS) iteration method and classical Uzawa method. We research on its semi-convergence properties and the eigenvalues distributions of its preconditioned matrix. The resulting GSTS–Uzawa preconditioner is used to precondition Krylov subspace methods such as the restarted generalized minimal residual (GMRES) method for solving the equivalent formulation of the complex singular saddle point problems. The theoretical results and effectiveness of the GSTS–Uzawa method are supported by a numerical example.

The derivation of joint operating policy is a challenging task for a multi-purpose multi-reservoir system. This study proposed an aggregation-decomposition model to guide the joint operation of multi-purpose multi-reservoir system, including: (1) an aggregated model based on the improved hedging rule to ensure the long-term water-supply operating benefit; (2) a decomposed model to allocate the limited release to individual reservoirs for the purpose of maximizing the total profit of the facing period; and (3) a double-layer simulation-based optimization model to obtain the optimal time-varying hedging rules using the non-dominated sorting genetic algorithm II, whose objectives were to minimize maximum water deficit and maximize water supply reliability. The water-supply system of Li River in Guangxi Province, China, was selected for the case study. The results show that the operating policy proposed in this study is better than conventional operating rules and aggregated standard operating policy for both water supply and hydropower generation due to the use of hedging mechanism and effective coordination among multiple objectives.

A family of bidirectional switched-capacitor (SC) converters with high-gain ratio of any positive integer is proposed in this paper for distributed energy resources applications. As compared with other existing SC converters achieving a same conversion gain, the main advantages of the proposed converters are that they require a relatively lower number of switches and capacitors, have a relatively lower switch's and capacitor's stress, and that their associated driver circuits are simpler to realize. Importantly, with the achievable conversion ratio being flexible and that the input and output of the proposed converters are of common ground, the proposed converters are widely suitable for many applications. Moreover, as the proposed converters do not possess magnetic component or any component that can severely degrade the converters’ performance at high temperature, they are especially useful for high-temperature applications. Besides, the proposed converters are capable of delivering bidirectional power, which is a key requirement for emerging applications with battery storages. Different aspects of the proposed converters, including a simple auxiliary power supply circuit for the MOSFETs’ drivers, will be discussed in this paper. A nine-time SC converter prototype that operates with 20-V input voltage, 100-W output, and at 75 kHz, is constructed and tested. Experiment results show that the maximum efficiency achievable with this prototype is over 98% (without driver's loss) and the efficiency over the entire load range between 25 and 100 W is over 95.5% including the driver's loss. The output voltage ripple of the SC converter is less than 1%. When the SC converter is open-loop controlled, the load voltage regulation is relatively well kept at less than 5% between full load and no load conditions.

Background Siglec-1 is highly expressed on circulating monocytes and plaque macrophages in atherosclerotic patients, but the exact role of Siglec-1 in atherosclerosis has not been elucidated. Methods Lentiviral vector containing small interfering RNA targeting Siglec-1 (Lv-shSiglec-1) or control vector (Lv-shNC) were injected intravenously into 6-week old Apoe −/− mice. Then onset of atherosclerosis was observed. Results Siglec-1 was highly expressed in aortic plaques and it can be down-regulated by Lv-shSiglec-1 injection. The plaque area and serum pro-inflammatory cytokine (IL-1β, IL-6, TNF-α and IL-17A) levels in Lv-shSiglec-1 mice were significantly lower than Lv-shNC mice, whereas IL-10 was higher. Moreover, plaque macrophages accumulation in aortic wall in Lv-shSiglec-1 mice was diminish, partly by decreased secretion of MCP-1/CXCL2 and CCR2/CXCR2 of aortas and monocytes, respectively. Furthermore, silencing of Siglec-1 can attenuate oxLDL uptake by peritoneal macrophages. Conclusions Inhibition of Siglec-1 can prevent atherosclerotic lesion formation by suppress monocytes-endothelial cells adhesion and macrophages accumulation.

The efficiency of inductive power transfer (IPT) system is highly related to the conditions of load and the compensation network. Combined with lithium battery charging characteristic, the transfer efficiency exhibits sharply decreasing in constant voltage (CV) mode in wireless electric vehicle (EV) charging system. This paper compares the light-load efficiency between LCC-Series (LCC-S) and LCC-Parallel (LCC-P) compensation networks under constant voltage (CV) charging mode. An efficiency optimization method is proposed for the LCC-P compensated wireless EV charging system, which is more suitable for the load variation during the constant voltage (CV) charging phase of the lithium battery. After the theoretical analysis is conduced, the MATLAB simulation and experiment were completed to prove the accuracy of the analysis result.

Pseudomonas aeruginosais one of the leading causes of opportunistic and hospital-acquired infections worldwide. The infection withP. aeruginosais frequently linked with clinical treatment difficulties given drug resistance and abuse of antibiotics. Ibuprofen, a widely used non-steroidal anti-inflammatory drug, has been previously reported to exert antimicrobial activity, although the specific mechanism of its action requires additional investigation. Given the regulation effects on quorum sensing (QS), we hypothesized that inhibition ofP. aeruginosawith ibuprofen is linked with the QS systems. First, we assessed the action of ibuprofen inP. aeruginosaby measuring CFU. The antimicrobial activity of ibuprofen was evaluated by crystal violent staining and acridine orange staining at various drug concentrations (0, 50, 75, and 100 μg/mL). Moreover, the effect of ibuprofen on different QS virulence factors, such as pyocyanin, elastase, protease, and rhamnolipids, was assessed revealing a concentration-dependent decrease (P12-HSL and C4-HSL production. In addition, qRT-PCR results identified significant suppression of Las and Rhl gene expression after 18 hours of treatment with ibuprofen (P12-HSL and C4-HSL suggested that C4-HSL can recover the production of virulence factors and biofilm formation inP. aeruginosa.Molecular docking of ibuprofen with QS-associated proteins revealed high binding affinity. In summary, the results suggest that ibuprofen is a candidate drug for the treatment of clinical infections withP. aeruginosa.

Emergent cadmium pollution can cause water quality deterioration in rivers, which destroys the aquatic eco-environment and poses threats to human health. Fish species in these aquatic systems are prone to such pollution incidents and act as important indicators of the pollution level. Because cadmium enters the systematic circulation of fish and is non-biodegradable, the investigation of cadmium accumulation in fish bodies provides insights into the detrimental effects of cadmium pollution on the aquatic biological system. This research aims to validate the eco-environmental risks associated with emergent cadmium pollution incidents based on the investigation of the different tissues and organs of diverse fish species. The investigation was conducted six times along the Longjiang River using sampling methods during which all fish species were also classified and analyzed based on the water layer they reside in and their feeding habits. The results show that the cadmium concentration in the fish tissues is significantly higher in the former three investigations compared with that of the latter three analyses. For herbivorous, carnivorous, and omnivorous fish species, the cadmium concentration of their different tissues and organs follows the order:kidneylivergutgilleggscale ≈ muscle. The cadmium concentration in the kidney is significantly higher (

High-voltage-gain and wide-input-range dc-dc converters are widely used in various electronics and industrial products such as portable devices, telecommunication, automotive, and aerospace systems. The two-stage converter is a widely adopted architecture for such applications, and it is proven to have a higher efficiency as compared with that of the single-stage converter. This paper presents a modular-cell-based morphing switched-capacitor (SC) converter for application as a front-end converter of the two-stage converter. The conversion ratio of this converter is flexible and variable and can be freely extended by increasing more SC modules. The varying conversion ratio is achieved through the morphing of the converter's structure corresponding to the amplitude of the input voltage. This converter is light and compact, and is highly efficient over a very wide range of input voltage and load conditions. Experimental work on a 25-W, 6-30-V input, 3.5-8.5-V output prototype, is performed. For a single SC module, the efficiency over the entire input voltage range is higher than 98%. Applied into the two-stage converter, the overall efficiency achievable over the entire operating range is 80% including the driver's loss.

Aluminum electrolytic capacitors (Al-Cap) are widely used in the DC-links of many power converters. Al-Cap is of low lifetime, which limits the reliability of the power converter. Therefore, it is important to predict the accurate lifetime of the Al-Cap to assist to design a high reliability power converter. At present, the lifetime prediction model of the Al-Cap is of low precision due to the ignorance of the influence of the AL-Cap’s equivalent series resistance (ESR) variation caused by the temperature. The varied ESR increases the energy loss of the Al-Cap, which leads to extra temperature risen. Therefore, this paper investigates the lifetime predication influenced by the ESR variations in an Al-Cap by using Simplorer and Icepak co-simulation. The temperature variation of the Al-Cap is obtained by the Simplorer and Icepak co-simulation. An accurate Al-Cap lifetime predication in a 1kW single-phase inverter is simulated. Simulation result shows that the accuracy of the Al-Cap’s lifetime with considering the ESR loss improved over 21% compared that without considering the ESR loss.

To explore the effects of different iron minerals on soil arsenic bioaccessibility, ferrihydrite, goethite and hematite were used in PBET, SBRC and IVG in-vitro experiments in this study. The relationship between arsenic bioavailability in gastric, small intestinal phases and arsenic speciation was also studied. The results showed that when 1% ferrihydrite was added, arsenic bioavailability in gastric phase was 2.22%, 5.11% and 7.43% by PBET, SBRC and IVG methods, respectively, while in the small intestinal phase it was 3.39%, 2.33% and 6.18%. At an elevated ferrihydrite dosage of 2%, significant difference in arsenic bioavailability was observed in both phases (

The safety of vegetable production is a key link in reducing cadmium consumption through the food chains. Field experiments were conducted to investigate the effects of composite materials (calcium silicate-biological humus fertilizer) on the growth of shallots and the uptake of Cd by shallots from contaminated agricultural soil. Four treatments (T1: 0.5% calcium silicate+0.5% biological humus fertilizer; T2: 0.5% calcium silicate+1.0% biological humus fertilizer; T3: 1.0% calcium silicate+0.5% biological humus fertilizer; and T4: 1.0% calcium silicate+1.0% biological humus fertilizer) and a control group (CK) were adopted. The changes in soil pH, DTPA-extractable Cd, biomass of shallots, and cadmium concentrations in shallots over time under different treatments were analyzed. The results show that the application of composite amendments decreased the concentrations of DTPA-extractable Cd in the soil. In particular, after T3 treatment, the concentrations of soil DTPA-extractable Cd decreased by 60.71%, 49.54%, 44.63%, and 58.94% after 14, 28, 42, and 56 d, respectively. The biomass of the shallots aboveground increased significantly by 107.99% and 107.19% after T3 and T4 treatment, respectively. The composite amendments exhibited different effects on the uptake of Cd by the shallots from the soil, and the T4 treatment was the most effective in immobilizing Cd and inhibiting translocation of Cd into the shallots. The cadmium concentration in the shallots decreased by 43.80% after 56 d with the T4 treatment. In conclusion, T4 is the optimum treatment for soil cadmium immobilization.

The massive release of soil arsenic and its enrichment in rice are significantly associated with the flooded and anaerobic management in paddy soil. Soil redox potential (Eh), pH and iron oxides exert remarkable impacts on arsenic release, which remain to be explored. In this study, long-term aerobic and anaerobic as well as intermittent aerobic incubation treatments were applied to investigate the influences of Eh, pH and iron content on arsenic release. It was found that anaerobic and flooded treatment contributed to the highest arsenic release. With decreasing Eh, significant enhancement in As(Ⅲ) and As(Ⅴ) contents in soil solution was observed. Particularly, As(Ⅲ) and As(Ⅴ) contents during the second phase increased by 1.37 and 0.99 μg·L

Vegetable is an indispensible component of human daily diet,and contamination of vegetables by heavy metals directly threatens human health.In this study,116 vegetable samples were collected from 12 administrative districts of Guangzhou City for analysis of six heavy metals,Cu,Zn,Pb,Cd,Ni,Cr.A combination of single factor evaluation and Nemero Index analysis was employed to determine specific heavy metals exceeding allowable standards and analyze the characteristics of pollution.Risk of exposure was utilized to assess human health risks originating from eating locally planted vegetables contaminated by heavy metals.The results showed that contents of Cu,Zn in the 8 sorts of vegetables were below the standards of maximum allowable content and the contents of heavy mental Cr of up to 91.67% vegetable samples were higher than their standard.

Arsenic toxicity, mobility and bioaccessibility are influenced by its different speciation in soil, which exerts different impacts on the environment. In this study, coal fly ash, dried sludge, ferrous sulfate and broken peanut shell were used as stabilizers to investigate their stabilizing effects on As in soil as well as relationships between pH, soil organic matter content, cation exchange capacity and speciation of soil As. The results showed rise in soil pH, soil organic matter content and residual arsenic content after the addition of stabilizers. Addition of 10% coal fly ash and 10% dried sludge led to the decrease in the content of exchangeable As, carbonate bound As, Fe-Mn oxide bound As, organic bound As by 34.2%, 17.5%, 19.9%, 53.7%, respectively. Addition of ferrous sulfate could preferably stabilize As in soil. When 10% coal fly ash, 10% dried sludge and 1% ferrous sulfate were added concurrently, the decrease in the content of exchangeable As, carbonate bound As, Fe-Mn oxide bound As, organic bound As was 62.3%, 55.2%, 29.6%, 58.2%, respectively, with an increase in residual arsenic content by 8.1%. After the addition of 10% coal fly ash, 10% dried sludge, 1% ferrous sulfate and 1% broken peanut shell, a most conspicuous decrease in the content of exchangeable As by 73.3% was observed. Appropriate application of coal fly ash, dry sludge and ferrous sulfate converted a proportion of exchangeable, carbonate bounded, Fe-Mn bounded, organic bounded As into residual As, which reduced As's toxicity. The rise in pH led to increasing residual As content and decreasing exchangeable As, carbonate bounded As, Fe-Mn bounded As and organic bounded As content, and As was most stable at the approach of neutral condition. The rise in organic matter content led to increasing carbonate bounded As and residual As content and decreasing exchangeable As, Fe-Mn bounded As, organic bounded As content. The rise in cation exchange capacity led to increasing residual As content and decreasing exchangeable As, carbonate bounded As, Fe-Mn bounded As and organic bounded As content.

Amorphous iron oxides in paddy soil are critical adsorbents of arsenic. The flooding period during rice cultivation contributes to the reductive dissolution of these amorphous iron oxides, which releases sorbed arsenic into the paddy soil solution. However, more detailed work should be conducted to evaluate quantitatively arsenic immobilization, release, and transformation regulated by metastable amorphous iron oxides. In previous studies, arsenic in the soil solution phase and solid phase were classified into F1 (exchangeable arsenic), F2 (specifically sorbed arsenic), F3 (amorphous iron oxide bound arsenic), and F4 (crystalline iron oxide bound arsenic), according to a sequential extraction procedure using reagents of increasing dissolution strength. In this study, soil samples were collected from the vicinity of a silver smelting plant in Chenzhou, Hunan Province, and the contribution of different arsenic speciation (F1, F2, F3, and F4) to arsenic release during anaerobic enrichment incubation of paddy soil was investigated. Sample analysis was conducted at the end of the first phase (day 15) and the second phase (day 30). The effects of amorphous iron oxides in paddy soil on migration and transformation of arsenic were discussed. Results showed significant elevation of dissolved Fe(Ⅱ) and arsenic concentration (

Salinity gradient power (SGP) between fresh river water and sea water is a form of renewable energy with huge potential but not well explored. This paper presents a feasibility study on energy harvesting of SGP based on: 1) the use of reverse electrodialysis (RED) stack, and 2) the combined use of harmonics-boosted resonant inverter and multistage diode-capacitor step-up converter. The properties of an RED stack have been characterized into steady-state ac and dc equivalent circuit models for power converter design for the first time. The gains of the resonant inverter and diode-capacitor step-up converter are also optimized for maximizing the energy efficiency. An RED stack prototype comprising multiple alternating anion and cation exchange membranes with an area of 0.01 m $^{\text 2}$ each has been constructed. The dc output voltage of 2–3 V from the RED stack has been stepped up to be over 155 V. This study has confirmed that energy can be harvested with a membrane power density of at least 1.4 W/m2, a power converter's efficiency exceeding 85%, and a voltage gain of 67.3 times.

Based on AOR and Uzawa methods, this paper presents Uzawa–AOR method for solving a class of singular saddle point problems. We analyze its semi-convergence and the distribution of the eigenvalues of its iterative matrix. The theoretical results and effectiveness of the Uzawa–AOR method are supported by a numerical example.

The basic leucine zipper (bZIP) transcription factors are the most diverse members of dimerizing transcription factors. In the present study, 50, 116, and 47bZIPgenes were identified inMalus domestica(apple),Prunus persica(peach), andFragaria vesca(strawberry), respectively. Species-specific duplication was the main contributor to the large number ofbZIPsobserved in apple. After WGD in apple genome, orthologousbZIPgenes corresponding to strawberry on duplicated regions in apple genome were retained. However, in peach ancestor, these syntenic regions were quickly lost or deleted. Maybe the positive selection contributed to the expansion of clade S to adapt to the development and environment stresses. In addition, purifying selection was mainly responsible forbZIPsequence-specific DNA binding. The analysis of orthologous pairs between chromosomes indicates that these orthologs derived from one gene duplication located on one of the nine ancient chromosomes in the Rosaceae. The comparative analysis ofbZIPgenes in three species provides information on the evolutionary fate ofbZIPgenes in apple and peach after they diverged from strawberry.

Establishment of symbiosis between legumes and nitrogen-fixing rhizobia depends on bacterial Nod factors (NFs) that trigger symbiosis-related NF signaling in host plants. NFs are modified oligosaccharides of chitin with a fatty acid moiety. NFs can be cleaved and inactivated by host enzymes, such as MtNFH1 (MEDICAGO TRUNCATULA NOD FACTOR HYDROLASE1). In contrast to related chitinases, MtNFH1 hydrolyzes neither chitin nor chitin fragments, indicating a high cleavage preference for NFs. Here, we provide evidence for a role of MtNFH1 in the symbiosis with

This paper presents a family of exponential voltage step-down switched-capacitor (ESC) converters. Considering the demand of large-voltage-gain step-down converters in the market, it is difficult to achieve the step-down requirement with good efficiency for a single-stage buck converter. The two-stage converter has been an effective solution for high-voltage-step-down applications. In this paper, making use of the large-voltage-gain conversion property of the ESC converter, a two-stage ESC-buck converter is proposed. A mathematical tool for the accurate calculation of efficiency is developed. The efficiency characteristic of the proposed ESC converter is established. Experimental efficiency measurements are carried out using the ESC converter proposed and two different types of commercially available buck converter ICs. The results show that the efficiency of the ESC-buck converter is higher than that of a single buck converter for large-voltage-gain applications.

C31H22N4O2Cl2Cu, orthorhombic, C2221 (no. 20), a = 6.869(2) Å, b = 18.535(7) Å, c = 21.199(7) Å, V = 2698.9(16) Å3, Z = 4, R gt(F) = 0.0385, wR ref(F 2) = 0.1036, T = 293 K.

Objectives. Elevated expression of Siglec-1 on circulating monocytes has been reported in some inflammatory and autoimmune diseases, but its expression and role in RA has not been elucidated. The aims of this study were to determine the expression of Siglec-1 in peripheral blood and to explore its role in mononuclear cell reactivity to autoantigen in RA. Methods. Siglec-1 protein and mRNA levels in 42 RA patients, 39 OA patients, 28 SLE patients and 42 normal controls were determined by flow cytometry and quantitative RT-PCR, respectively. In addition, 10 patients with active RA received DMARDs for 12 weeks and the frequencies of Siglec-1-positive cells and the 28-joint DAS (DAS28) were assessed before and after therapy. Furthermore, TNF-a, IFN-g and type II collagen were used to up-regulate Siglec-1. Peripheral blood mononuclear cells (PBMCs) from different groups were stimulated with mitogens or antigens and cell proliferation and cytokine production were determined. Results. The protein and mRNA levels of Siglec-1 on PBMCs and monocytes in RA patients were significantly higher than those in OA patients and healthy controls. Moreover, the expression of Siglec-1 protein on PBMCs was positively correlated with DAS28, ESR, high-sensitivity CRP and IgM-RF, but not with anti-CCP antibody. Interestingly, Siglec-1 expression was decreased in parallel with the decrease in the DAS28 after 12 weeks of anti-rheumatic treatment. Furthermore, TNF-a, IFN-g and type II collagen can up-regulate Siglec-1 in PBMCs. Elevated PBMC proliferation and proinflammatory cytokine production to collagen stimulation in RA patients decreased when Siglec-1 was inhibited by anti-Siglec-1 antibodies. Conclusion. Elevated Siglec-1 expression in PBMCs and monocytes can potentially serve as a biomarker for monitoring disease activity in RA. Siglec-1 may also play a proinflammatory role in stimulating lymphocyte proliferation and activation in RA.

A non-isolated high-step-up resonant DC/DC converter made up of a resonant inverter and a passive switched-capacitor (SC) rectifier, is proposed in this paper. The proposed converter is free of transformer and coupled-inductor. Thus, issues related to the leakage inductance and the large volume magnetic component caused by large turn's ratio of high-voltage-gain applications, are avoided. Besides, as the converter contains only one active switch, its control is simple. Second harmonic voltage across the switch is attenuated to provide low voltage stress for the active switch and a higher voltage gain of the converter. The voltage gain of the converter is not achieved by a single stage, but by the gain product of the resonant inverter and SC rectifier. A prototype with input voltage 6 V, 500 kHz switching frequency, 50% duty cycle, is constructed to validate the performance of the proposed converter. The voltage gain of the prototype is over 33 times and the achievable efficiency is close to 90% under a wide load resistance range.

A compact modular switched-capacitor DC/DC converter with exponential voltage gain, high efficiency, light weight, and bidirectional power flow, is proposed in this paper. The proposed converter is suitable for applications in high temperature environments since it does not contain magnetic element nor temperature-sensitive capacitor. With an output voltage that is 2N (N is the cell number) times the low-side voltage, the proposed converter has a considerably low component count and suffers from the lowest overall capacitor voltage stress as compared with other existing switched-capacitor converters. Besides, the proposed converter adopts a modular structure and simple control scheme, which enables it to be easily extended, through a repeated cascade of the same module, to achieve a higher voltage conversion. Moreover, since the load is charged via two complementary paths in an interleaved operation, the output voltage ripple is small, which is beneficial for high efficiency. Experimental results of an 8×-gain prototype at 5 V input and 70 W output power, are provided to validate the performance of the proposed converter. The achievable efficiency is up to 95.78% (including the driver's loss).