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This letter presents a highly efficient and wide input range maximum power point tracking (MPPT) circuit for energy harvesting systems (EHSs). The conventional MPPT circuit shows attenuation of the power conversion efficiency (PCE) at low input voltages due to insufficient distribution of conversion ratio (CR) in switched capacitor (SC) dc–dc converters. To overcome this critical issue, the proposed circuit implements coarse and fine stages to increase the number of CR. The proposed MPPT operation can be accurately achieved with CR tuning only (without switching frequencies), which results in high PCE. This work is fabricated in the 180‐nm CMOS process and measured with the commercial photovoltaic (PV) cells to demonstrate the advantages of the proposed circuit. The measurement results show that the EHS achieves a flat and improved PCE over a wide input range of 0.4 to 1.6 V. The PCE is as high as 88% for an output power below 50 μW and the active area occupies 1.2 mm2. [ABSTRACT FROM AUTHOR]

Deubiquitinating enzymes (DUBs) play an important role in the ubiquitin‐proteasome system (UPS) by eliminating ubiquitins from substrates and inhibiting proteasomal degradation. Protein phosphatase methylesterase 1 (PME‐1) inactivates protein phosphatase 2A (PP2A) and enhances the ERK and Akt signaling pathways, which increase cell proliferation and malignant cell transformation. In this study, we demonstrate that USP36 regulates PME‐1 through its deubiquitinating enzyme activity. USP36 increases PME‐1 stability, and depletion of USP36 decreases the PME‐1 expression level. Furthermore, we demonstrate that USP36 promotes the ERK and Akt signaling pathways. In summary, it is suggested that USP36 regulates PME‐1 as a DUB and participates in the ERK and Akt signaling pathways. [ABSTRACT FROM AUTHOR]

RNA-binding protein with serine-rich domain 1 ( RNPS1) is a component of pre-splicing and post-splicing multiprotein complexes, which activates constitutive and alternative splicing. RNPS1 participates in the formation of the spliceosome and activates the pre- mRNA splicing process. In the present study, we found that ubiquitin-specific protease 4 ( USP4) is a binding partner of RNPS1. Although RNPS1 is polyubiquitinated by both K48- and K63-linkages, USP4 exclusively deubiquitinates K63-linked polyubiquitin chains of RNPS1. We also demonstrate that the catalytic activity of USP4 on ubiquitinated RNPS1 is elevated by squamous cell carcinoma antigen recognized by T cells 3 (Sart3). [ABSTRACT FROM AUTHOR]

This paper investigated the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of silky hairs of corn (Zea mays L.) which is a waste material of the crop, as both a reducing and stabilising/capping agent. The AgNPs were characterised by UV‐visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X‐ray analysis (EDX), thermogravimetric analysis (TGA), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT‐IR). The average size of AgNPs was found to be 249.12 nm. The AgNPs displayed strong antibacterial activity against five different foodborne pathogenic bacteria with diameter of inhibition zones ranged between (9.23 − 12.81 mm). It also exhibited potent synergistic antibacterial activity together with standard antibiotics, kanamycin (10.6 − 13.65 mm inhibition zones) and rifampicin (10.02 − 12.86 mm inhibition zones) and anticandidal activity with amphotericin b (10.57 − 13.63 mm inhibition zones). The AgNPs exhibited strong antioxidant activity in terms of nitric oxide scavenging (IC50 91.56 µg/mL), ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) radical scavenging (IC50 115.75 µg/mL), DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) radical scavenging (IC50 385.87 µg/mL), and reducing power (IC0.5 23.14 µg/mL). This study demonstrated the synthesis of spherical AgNPs with strong antibacterial, anticandidal and antioxidant properties that could potentially be utilised in the biomedical, cosmetic, food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Bacteria utilize signal molecules to ensure their survival in environmental niches, and indole is an interspecies and interkingdom signalling molecule, which is widespread in the natural environment. In this study, we sought to identify novel roles of indole in soil-borne bacterium A grobacterium tumefaciens. A grobacterium tumefaciens was found not to synthesize indole and to degrade it rapidly. The addition of exogenous indole dose-dependently inhibited A . tumefaciens growth and decreased its motility. Surprisingly, indole markedly increased A . tumefaciens biofilm formation on polystyrene, glass and nylon membrane surfaces and enhanced its antibiotic tolerance. Transcriptional analysis showed that indole markedly up-regulated several biofilm-related ( celA, cheA, exoR, phoB, flgE, fliR and motA), stress-related genes ( clpB, dnaK, gsp, gyrB, marR and soxR) and efflux genes ( emrA, norM, and A tu2551) in A . tumefaciens, which partially explained the increased biofilm formation and antibiotic tolerance. In contrast, the plant auxin indole-3-acetic acid did not affect biofilm formation, antibiotic tolerance or gene expression. Interestingly, indole was found to exhibit several similarities with antibiotics, as it inhibited the growth of non-indole-producing bacteria, whereas these bacteria countered its effects by rapidly degrading indole, and by enhancing biofilm formation and antibiotic tolerance. [ABSTRACT FROM AUTHOR]

This study examined the antibacterial mode of action of T axus cuspidata leaf essential oil ( TCEO) against foodborne pathogenic bacteria. Gas chromatography-mass spectrometry analysis of microwave-extracted TCEO resulted in examination of 34 different compounds, representing 81.63% of the total oil. The TCEO (1,000 μg per disc) showed antibacterial effect against B acillus cereus ATCC 13061, S taphylococcus aureus ATCC 12600, L isteria monocytogenes ATCC 7644, S almonella typhimurium ATCC 43174 and E scherichia coli ATCC 43889 as diameters of inhibition zones (22.0 ± 0.4 to 34.0 ± 1.2 mm). The minimum inhibitory concentration and minimum bactericidal concentration values of TCEO against the tested pathogens were found in the range of 250-1,000 μg/mL. Also, the TCEO had potential inhibitory effect on the viable counts of test pathogens. The TCEO revealed its mode of action on membrane integrity as confirmed by marked release of extracellular adenosine triphosphate, 260 nm absorbing materials and potassium ion efflux. The scanning electron microscopy analysis using TCEO further confirmed severe morphological alterations on the cell membrane of test pathogens. Practical Applications Because of frequent foodborne outbreaks and rising concern of consumers on the use of chemical preservatives in foods, the food industry is emphasizing the use of natural antibacterial agents from plant origin as safe food preservatives. Some selected plant materials are used as natural antimicrobials in food systems to prevent the growth of foodborne pathogens, resulting in the extension of shelf life of processed foods. T axus cuspidata leaf essential oil ( TCEO) is shown by this study to elicit its antibacterial action against foodborne pathogens through membrane permeabilization and can be used to control the growth of several foodborne pathogens. Hence, it is anticipated that TCEO may have greater potential for its practical application as an affective food preservative. [ABSTRACT FROM AUTHOR]

This study investigated the antibacterial mechanism of action of the seed essential oil of Eleutherococcus senticosus ( ESEO) against foodborne pathogenic bacteria. Preliminarily, the ESEO (1000 μg disc−1) showed potential antibacterial effect as diameter of inhibition zones (12.0 ± 0.2-37.0 ± 2.0 mm) against the tested foodborne pathogens. The MIC and MBC values of ESEO against the tested bacteria were found in the range of 125-500 and 500-1000 μg mL−1, respectively. At MIC concentration, the ESEO had potential inhibitory effect on the cell viability of the tested pathogens. In addition, SEM analysis showed the inhibitory effect of ESEO as confirmed by considerable morphological alterations on the cell wall of B. cereus ATCC 13061 and E. coli O157:H7 ATCC 43889. Moreover, the ESEO revealed its mode of action against foodborne pathogens on membrane integrity as confirmed by release of extracellular ATP, 260-nm absorbing materials and leakage of potassium ions. These findings confirm that the ESEO can be used as a potential antibacterial agent in food industry to inhibit the growth of various foodborne pathogens. [ABSTRACT FROM AUTHOR]

This study examined the antibacterial mechanism of action of Taxus cuspidata stem essential oil ( TCEO) against foodborne pathogenic bacteria. The TCEO (2,000 μg/disc) showed potential antibacterial effect as diameters of inhibition zones (32.0 ± 0.47-44.0 ± 0.59 mm) against the tested foodborne pathogens including Bacillus cereus ATCC13061, Listeria monocytogenes ATCC7644, Staphylococcus aureus ATCC12600, Salmonella typhimurium ATCC43174 and Escherichia coli ATCC43889. The minimum inhibitory concentration and minimum bactericidal concentration values of TCEO against the tested bacteria were found in the range of 125-500 μg/m L and 250-1,000 μg/m L, respectively. Also, the TCEO had potential inhibitory effect on the cell viability of B. cereus ATCC 13061 and E. coli ATCC 43889. Moreover, the TCEO revealed its mode of action on membrane integrity as confirmed by marked release of extracellular adenosine 5′-triphosphate, 260-nm absorbing materials and efflux of potassium ions ( K+) against the tested pathogens. Further, scanning electron microscopic analysis also supported the inhibitory effect of TCEO as confirmed by significant morphological alterations on the cell membrane of the tested pathogens, suggesting its potential efficacy as a natural antibacterial agent. Practical Application Currently, because of frequent foodborne outbreaks and the rising concern of consumers on the use of chemical preservatives in foods, the food industry is emphasizing the use of natural antibacterial agents of plant origin as safe food preservatives. Some selected plant materials are used as natural antimicrobials in food systems to prevent the growth of foodborne pathogens, resulting in the extension of the shelf-life of processed foods. This study confirmed that Taxus cuspidata stem essential oil showed its antibacterial mode of action against foodborne pathogens through membrane permeabilization and can be used to control the growth of several foodborne pathogens. Hence, it is anticipated that T. cuspidata stem essential oil may have greater potential for its practical applications as an affective and natural food preservative against food deterioration caused by foodborne pathogens. [ABSTRACT FROM AUTHOR]

Twenty-two wild, 16 intermediate and 20 cultivated soybean varieties were used to analyse relationships among the species of subgenus Soja, genus Glycine using 11 morphological traits and simple sequence repeat ( SSR) markers. These genotypes using eleven agronomic characteristics were divided into three clusters: cluster I included 20 G. max, cluster II included 12 intermediate, and cluster III included 22 G. soja and four intermediate lines. Genetic relationships among the species of subgenus Soja showed three distinct clusters. Cluster I consisted of 20 G. max cultivars and two intermediate type lines, and cluster II consisted of 13 intermediate type and two G. soja lines; however, cluster III consisted of 20 G. soja and one intermediate type lines. These phenotypic and genetic data suggest that the intermediate type lines could be distinguished between G. max and G. soja lines. However, the intermediate type could not be classified as a new species. [ABSTRACT FROM AUTHOR]

This study investigates the antibacterial mechanism of action of Allium sativum rhizome essential oil ( ASEO) against foodborne pathogens. The ASEO was obtained by hydrodistillation of A. sativum rhizome using a microwave-assisted extraction technique. The ASEO (1,000 μg/disk) showed potential antibacterial effect as diameters of inhibition zones against the tested foodborne pathogens including American Type Culture Collection (ATCC) strains Bacillus cereus ATCC 13061, Escherichia coli ATCC 43889, Listeria monocytogenes ATCC 7644, Salmonella Typhimurium ATCC 43174 and Staphylococcus aureus ATCC 12600, which were found in the range of 11.0 ± 0.1-24.0 ± 0.1 mm. The minimum inhibitory concentration ( MIC) and minimum bactericidal concentration ( MBC) values of ASEO against the tested bacteria were found in the range of 62.5-500 μg/mL. At the MIC concentration, ASEO had potential inhibitory effect on the cell viability of the tested bacteria. In addition, the scanning electron microscopy analysis showed the inhibitory effect of ASEO as confirmed by the considerable morphological alterations on the cell walls of B. cereus ATCC 13061 and E. coli ATCC 43889. Moreover, the ASEO revealed its mode of action on membrane integrity as confirmed by the release of extracellular adenosine 5′-triphosphate, 260-nm absorbing materials and potassium ions efflux against tested pathogens. These findings suggest that ASEO showed its effect on membrane permeability and surface characteristics. Practical Applications Foodborne pathogens are the leading causes of illness in the developed countries. These pathogens are responsible for millions of cases of infectious diseases each year, costing billions of dollars in medical care. New foodborne pathogens and foodborne diseases are likely to emerge driven by factors such as pathogen evolution, changes in food manufacturing practices, and changes to the human host status. Fuelled by these concerns, research on biologically active natural compounds to control the foodborne pathogens has escalated to unprecedented levels in recent years. Plant-based antimicrobials such as essential oils have been found to suppress the growth of foodborne pathogens in various in vitro and in vivo models. These findings clearly indicate that essential oil derived from the rhizome of A. sativum confers its mode of action on membrane integrity, hence, could be used as an affective candidate to control the growth of certain important foodborne pathogens in practical applications. [ABSTRACT FROM AUTHOR]

Certain group I introns insert into intronless DNA via an endonuclease that creates a double-strand break (DSB). There are two models for intron homing in phage: synthesis-dependent strand annealing (SDSA) and double-strand break repair (DSBR). The Cr.psbA4 intron homes efficiently from a plasmid into the chloroplast psbA gene in Chlamydomonas, but little is known about the mechanism. Analysis of co-transformants selected using a spectinomycin-resistant 16S gene (16Sspec) provided evidence for both pathways. We also examined the consequences of the donor DNA having only one-sided or no homology with the psbA gene. When there was no homology with the donor DNA, deletions of up to 5 kb involving direct repeats that flank the psbA gene were obtained. Remarkably, repeats as short as 15 bp were used for this repair, which is consistent with the single-strand annealing (SSA) pathway. When the donor had one-sided homology, the DSB in most co-transformants was repaired using two DNAs, the donor and the 16Sspec plasmid, which, coincidentally, contained a region that is repeated upstream of psbA. DSB repair using two separate DNAs provides further evidence for the SDSA pathway. These data show that the chloroplast can repair a DSB using short dispersed repeats located proximally, distally, or even on separate molecules relative to the DSB. They also provide a rationale for the extensive repertoire of repeated sequences in this genome. [ABSTRACT FROM AUTHOR]

Abstract: Recognition of phosphorylated serine/threonine-containing motifs by 14-3-3 depends on the dimerization of 14-3-3. However, the molecular cues that control 14-3-3 dimerization are not well understood. In order to identify proteins that control 14-3-3 dimerization, we analyzed proteins that have effects on 14-3-3 dimerization and report that protein kinase A (PKA) phosphorylates 14-3-3ζ at a specific residue (Ser58). Phosphorylation by PKA leads to modulation of 14-3-3ζ dimerization and affect its interaction with partner proteins. Substitution of Ser58 to Ala completely abolished phosphorylation of 14-3-3ζ by PKA. A phospho-mimic mutant of 14-3-3ζ, Ser58 to Glu substitution, failed to form homodimers, showed reduced interaction with 14-3-3ε and p53, and could not enhance transcriptional activity of p53. Moreover, activation of PKA decreases and inhibition of PKA increases the dimerization of 14-3-3ζ and the functional interaction of 14-3-3ζ with p53. Therefore, our results suggest that PKA is a new member of protein kinases that can phosphorylate and impair the function of 14-3-3. [Copyright &y& Elsevier]

Abstract: The tumor suppressor protein p53 is ubiquitinated and neddylated by MDM2 and then degraded by 26S proteasome. However, p53 is stabilized by the HAUSP (Herpes-virus-associated ubiquitin-specific protease) deubiquitinating enzyme. In this study, we discovered that rat HAUSP (rHAUSP) is polyubiquitinated, polyneddylated, and dimerized using co-immunoprecipitation assays. This suggests that rHAUSP may function as a dimer or multimer and is also degraded through the proteasome-mediated degradation. Transfection of rHAUSP into RGC-Lac-Z cell line with the integrated p53 response element revealed that rHAUSP contributed to p53 stabilization, and a rHAUSP (C224S) mutant contributed to p53 destabilization in a dose-dependent manner. [Copyright &y& Elsevier]

An energy‐efficient capacitor switching digital‐to‐analogue converter (DAC) is proposed for successive‐approximation register analogue‐to‐digital converters (SAR ADCs). The proposed charge‐average switching with floating capacitors (CASFCs) DAC disconnects the most significant bit (MSB) capacitors from the capacitor array after determining the MSB. The switching energy of the proposed CASFC DAC is lower than that of the recently published DAC, because the CAS technique is only employed in the CASFC DAC, while both the traditional and CAS methods are used in the previous DAC depending on inputs. In addition, the energy during the reset period is also minimised because the floated MSB capacitors do not consume the reset energy. The CASFC DAC reduces the switching energy with and without reset by 64.4 and 37.5%, respectively, compared with the aforementioned previous DAC. [ABSTRACT FROM AUTHOR]