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Philodendrons are important foliage ornamentals planted worldwide (Chen et al. 2010). In November 2021, soft rot symptoms were observed on

A novel voltage-doubling circuit with parallel-resonant dc–dc converter is proposed. The converter consists of full-bridge inverter, resonant tank, high-frequency high-voltage transformer, and voltage-doubling circuit. In the high-voltage applications, low-output voltage ripple has been given much attention. The output voltage step-up ratio is increased by two parts. One is a high-frequency high-voltage transformer and the other is a voltage-doubling circuit. The novel voltage-doubling circuit can not only reach a higher output voltage but also reduce output ripple to a lower level than the conventional one. Therefore, while maintaining the same output voltage, the transformer's turn ratio can be reduced compared with the conventional voltage-doubling circuit. The output power can be adjusted by the phase-shift control technique. In addition, combining this technique with the parallel resonant tank can make all the switches achieve zero voltage turn on (ZVS). The operating principles, steady-state analysis, and the parameter designs are discussed in this paper. Finally, a prototype circuit with 400-V input voltage, 40-kV output voltage, and 300-W output power is developed in the laboratory to verify the performance of the proposed converter.

This paper compares the microstructure and electrochemical properties of the diamond-like carbon films obtained by two different deposition methods - microwave electron cyclotron resonance plasma enhanced chemical vapor deposition (MWECR-PECVD) techniques and electro-deposition – chosen for their low cost and capacity to produce films. The microstructure of the DLC films are investigated by Raman spectroscopy, FTIR spectroscopy, and electrochemical behavior is investigated by potentiodynamic and electrochemical impedance spectroscopy (EIS). Raman spectroscopy indicates that all the films deposited by different techniques show amorphous structure and typical characteristic of DLC film. FTIR spectrum results indicate that these DLC films are a-C:H films. As a result of EIS, the DLC films made by different methods showed obviously different electrochemical characters. The obtained results show that the DLC films deposited using the PECVD methods provided the better results, presenting a high corrosion resistance , high adherence to substrate, and a denser and more uniform surface.

Based on Shandong Renping Bayer red mud as the raw material, analyzing its basic characteristics, the result is that the content of total iron in red mud is 29.55%. Gas-based high-temperature direct reduction experiments are made by using a gas mixture of CO and H2O as a reducing agent. And then the reduction effect was investigated by magnetic separation experiments, to realize that separation of iron minerals from red mud. The results show that the consequent of the magnetic separation is improved obviously with the temperature rising. Under these conditions, namely, the roasting temperature being 1050°C, the roasting time lasting 90 minutes, the reduction gas rate being 0.7 m3/min, the magnetic field being 2.2A, and three magnetic separations, the iron recovery ratio in red mud is over 97%.

Multiple pathways contribute to nonalcoholic fatty liver disease (NAFLD) in response to high fat diets (HFD). A homolog of mammalian JNK-interacting protein 3 (JIP3), also known as JSAP-1, activates different components in various signaling pathways to modulate cellular processes. The purpose of this study was to examine the role of JIP3 in obesity-related pathologies pathway. Wild-type (WT) C57BL/6 and JIP3-knockout (JIP3-/-) mice were randomized to chow or HFD. HFD-fed WT mice increased hepatic JIP3 expression. Mice lacking JIP3 exhibited reduced weight gain, hepatic steatosis, insulin resistance, lipid accumulation, oxidative stress and inflammatory response in mice fed a HFD, which were, importantly, dependent on various signaling pathways. Lipogenesis-linked pathway was inhibited in JIP3-/- mice after HFD, while PPARα/γ were increased. Additionally, JIP3-/- inhibited hepatic oxidative stress, evidenced by down-regulation of total reactive oxygen species (ROS), H2O2, O2-, malondialdehyde (MDA), xanthine oxidase (XO), inducible nitric oxide synthase (iNOS), and up-regulation of superoxide dismutase (SOD) and total antioxidant capacity (TAC) in mice after HFD feeding, which might be related to nuclear respiratory factor 2 (Nrf-2) pathway activation. Further, inflammatory response was blocked in JIP3-/- mice fed with HFD. The process might be attributed to the suppression of toll-like receptors (TLRs), p-nuclear factor kappa B (NF-κB) and p-c-Jun-N-terminal kinase (JNK). Thus, JIP3 absence is associated with decreased lipogenesis, oxidative stress and inflammation, supplying a new target for NAFLD treatment.

A low-cost raw material, bittern obtained from the production process of sea salt, was used to prepare magnesium oxysulfate hydrate (MgSO4·5Mg (OH)2·2H2O, abbreviated as 152MOS) whiskers via hydrothermal synthesis with ammonia and magnesium sulfate as the other starting raw materials. The bittern was firstly filtered and then used directly without de-coloring. X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) were employed to investigate the composition and morphology of the products. It was found that the 152MOS whiskers synthesized from bittern at 190°C for 3 hours exhibited fanlike morphology. The formation of the fanlike whiskers was inhibited and most of the whiskers presented as single fibers when ethanol was used as crystal control agent in the hydrothermal process. From the two-dimensional steps observed at tips of the whiskers, a possible growth mechanism was speculated that it was the extension of dislocations that made the growth of the whiskers.

This study aimed to assess the effect of hemoglobin A1C (HbA1C) detection on the diagnostic screening for glucose metabolic disorders in women with polycystic ovary syndrome (PCOS).A total of 161 patients with PCOS (mean age = 23.68 +/- 4.23 years) were subjected to an oral glucose tolerance test (OGTT). The receiver operating characteristic (ROC) curve was plotted to evaluate the fasting plasma glucose (FPG), and HbA1C was used to probe the sensitivity and specificity of abnormal glucose tolerance.Based on the traditional standards of blood sugar, the prevalence of type 2 diabetes was 5.6%, and the pre-diabetes prevalence was 7.5%. Based on the HbA1C standards, 4.3% of patients were diagnosed with type 2 diabetes, and 10.6% of the diabetic patients can be considered as high-risk populations. Based on the combined standards of OGTT and HbA1C, the prevalence of type 2 diabetes was 6.2%, and the pre-diabetes prevalence was 12.4%. OGTT is considered the gold standard for identifying abnormal glucose tolerance, and HbA1C detection is considered to be stronger than FPG. The areas under the ROC curves of HbA1C and FPG were 0.968 and 0.672, respectively (p0.01). The American Diabetes Association (ADA) recommends the cut-off value of HbA1cor = 5.7% and FPGor = 5.6 mmol/l for identifying abnormal glucose tolerance. The sensitivity and specificity were 76.7% and 89.5% for HBA1C, as well as 40.5% and 94.3% for FPG, respectively. The positive and negative likelihood ratios were 7.3 and 0.26 for HbA1C, as well as 7.1 and 0.63 for FPG, respectively.HbA1C detection can be used as a method for diagnosis and screening.

study question: Is there an association between exposure to phthalates and the timing of female puberty? summaryanswer: Our study suggests that the early onset of puberty is related to increased kisspeptin secretion. what is known already: Girls are maturing earlier than in past decades and the quantity of phthalates used in consumer products has concurrently risen. The hypothesis that exposure to phthalates may increase kisspeptin secretion and thereby cause early-onset puberty is unexplored. studydesign,size,duration: This case– control study ran from 2006 to 2009. We enrolled 104 girls. Girls in the central precocious puberty (CPP) (case) group were recruited from a pediatric endocrinology policlinic in Taiwan; prepubescent controls were recruited from local elementary schools and all were categorized based on a pediatrician’s diagnosis. participants/materials, setting, methods: The physical characteristics of puberty were assessed and levels of LH, FSH estradiol and kisspeptin-54 in blood samples were evaluated using radioimmunoassay. Reversed-phase high-performance liquid chromatography-tandem mass spectrometry was used to analyze seven urinary phthalate metabolites. Non-parametric analyses, trend tests and linear regressions were performed on the data. main results and the role of chance: All seven urinary phthalate metabolites in the CPP group were significantly (P , 0.05) higher than in prepubescent controls. Serum kisspeptin-54 levels were higher (P ¼ 0.022) in the CPP group than controls and were still significantly higher after adjusting for age (P ¼ 0.03). There was a significant increasing trend (Ptrend ¼ 0.005) between levels of kisspeptin and the stages of puberty. The concentration of kisspeptin-54 did not change in girls treated with leuprorelin acetate. There was a significant positive correlation between kisspeptin-54 and urinary mono-n-butyl phthalate (ng/ml: R 2 ¼ 0.251, P , 0.001; mg/g-creatinine: R 2 ¼ 0.109, P ¼ 0.024). limitations, reasons forcaution: The study duration was short and the sample size relatively small; therefore, we were unable to collect sufficient evidence to support the temporality between exposure to phthalates and the subsequent occurrence of PP. wider implications of the findings: Kisspeptin may promote the onset of puberty in girls who are exposed to a high level of phthalates, especially di-n-butyl phthalate. These data suggest that developing a kisspeptin antagonist might be an alternative strategy for treating PP.

Aqueous two-phase copolymerization of acrylamide (AM) and dimethylaminoethyl methacrylate methyl chloride (DMMC) was carried out in polyethylene glycol 20000 (PEG 20000) aqueous solution and with 2,2'-azobis(2- amidinopropane) dihydrochloride (V-50) as the initiator. The effects of the temperature, the PEG 20000 concentration, the DMMC/AM molar ratio and the V- 50 concentration on the initial monomer copolymerization rate (Rp), the total monomers conversion and the molecular weight of copolymers were systematically investigated. The initial copolymerization rate increased with an increase of temperature and V-50 content, contrary to the concentration of the PEG 20000 and DMMC. The molecular weight of the copolymers decreased with increasing the reaction parameters above mentioned. The apparent copolymerization activation energy of the system was calculated to be 65.7 kJ·mol-1 according to Arrhenius equation. The optimal PEG 20000 content of the system was 15%~25% (based on the raw materials). The relationship between the initial copolymerization rate (Rp) and the initiator concentration was discussed, and the kinetics equation was Rp~ [I]0.94.

In intra mode prediction, obtaining the best solution among all supported modes requires extremely high computation. Most fast search algorithms use a reduced search set to avoid this problem. Yet, these methods greatly degrade picture quality and increase bitstream size if very limited computational resource is applicable. In this paper, we proposed a scheme, which allows us to take extensive advantage of correlation within a video sequence. Prediction errors and modes of neighboring blocks are employed in our mode prediction scheme. The proposed method can either work alone or with existing direction detection methods to significantly reduce computation without losing much performance.

Variable-speed control systems utilizing hysteresis-controlled PWM technology which allows sinusoidal drive, have been widely applied to induction motors in recent years. High-performance hysteresis-controlled PWM inverters must have low error current and small harmonic contents. In traditional hysteresis control schemes the maximum error current can reach twice the hysteresis band. To suppress the error current and harmonic contents, a double hysteresis-controlled method based on the single hysteresis-controlled scheme has been proposed in this paper. Finally, experimental results show good agreement with the anticipated performance. >

We present an RC-model approach for understanding and analysis of holographic storage in photorefractive materials. In this model the resistor, capacitor and the current source are completely defined based on material parameters and light intensities. The model has good accuracy for the practical applications. It can also be used to understand and improve the properties of photorefractive materials for holographic recording. One interesting application of the model is the qualitative analysis of two-center recording. We also discuss this application in detail.

Purpose 2,3-Oxidosqualene cyclase (OSC), an important enzyme of cholesterol biosynthesis, catalyzes the highly selective cyclization of 2,3-monoepoxysqualene to lanosterol. Intermittent hypoxia (IH) is a hallmark feature in obstructive sleep apnea (OSA) which is increasingly recognized as an independent risk factor for liver injury. The aim of this study was to determine the effect of IH on OSC expression and evaluate the role of OSC in the IH-induced apoptosis in hepatic cell line human liver cell (HL-02). Methods HL-02 cells were exposed to normoxia or IH. Cell Counting Kit-8 (CCK-8) assay was used to value cell proliferation, and flow cytometry was used to determine cell apoptosis. The expression of OSC messenger RNA (mRNA) was evaluated by quantitative real-time PCR, and the expression of OSC protein was determined by Western blot. To further investigate the function of OSC in IH-induced apoptosis, oxidosqualene cyclase-enhanced green fluorescence protein (OSC-EGFP) plasmid was constructed to over-express OSC protein. Triglyceride content in HL-02 cells was analyzed by oil red staining or Triglyceride Quantification Kit. Results We found that IH inhibited HL-02 cell proliferation and accelerated cell apoptosis. IH decreased OSC expression, and over-expression of OSC could protect HL-02 cells against the IH-induced hepatic cell injury. Moreover, over-expression of OSC could attenuate IH-induced cellular triglyceride accumulation. Conclusions These findings suggest that OSC are involved in IH-induced hepatic cell injury. These results may contribute to the further understanding of the mechanism underlying the liver injury in OSA patients.