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91.
A new class of layered cathodes, Li[NixCoyB1?x?y]O2 (NCB), is synthesized. The proposed NCB cathodes have a unique microstructure in which elongated primary particles are tightly packed into spherical secondary particles. The cathodes also exhibit a strong crystallographic texture in which the ab layer planes are aligned along the radial direction, facilitating Li migration. The microstructure, which effectively suppresses the formation of microcracks, improves the cycling stability of the NCB cathodes. The NCB cathode with 1.5 mol% B delivers a discharge capacity of 234 mAh g?1 at 0.1 C and retains 91.2% of its initial capacity after 100 cycles (compared to values of 229 mAh g?1 at 0.1 C and 78.8% for pristine Li[Ni0.9Co0.1]O2). This study shows the importance of controlling the microstructure to obtain the required cycling stability, especially for Ni‐rich layered cathodes, where the main cause of capacity fading is related to mechanical strain in their charged state.  相似文献   
92.
Bioprocess and Biosystems Engineering - The β-glucanase produced from Bacillus sp. CSB55 not only depicts the potent industrial characteristics but also relates as bio-industrial catalyst...  相似文献   
93.
Interactions between pathogenic microorganisms and their hosts are varied and complex, encompassing open-field scale interactions to interactions at the molecular level. The capacity of plant pathogenic bacteria and fungi to cause diseases in human and animal systems was, until recently, considered of minor importance. However, recent evidence suggests that animal and human infections caused by plant pathogenic fungi, bacteria and viruses may have critical impacts on human and animal health and safety. This review analyses previous research on plant pathogens as causal factors of animal illness. In addition, a case study involving disruption of type III effector-mediated phagocytosis in a human cell line upon infection with an opportunistic phytopathogen, Pseudomonas syringae pv. tomato, is discussed. Further knowledge regarding the molecular interactions between plant pathogens and human and animal hosts is needed to understand the extent of disease incidence and determine mechanisms for disease prevention.  相似文献   
94.
Glucose controls the phosphorylation of silent information regulator 2 (Sir2), a NAD+‐dependent protein deacetylase, which regulates the expression of the ATP‐dependent proton pump Pma1 and replicative lifespan (RLS) in yeast. TORC1 signaling, which is a central regulator of cell growth and lifespan, is regulated by glucose as well as nitrogen sources. In this study, we demonstrate that TORC1 signaling controls Sir2 phosphorylation through casein kinase 2 (CK2) to regulate PMA1 expression and cytoplasmic pH (pHc) in yeast. Inhibition of TORC1 signaling by either TOR1 deletion or rapamycin treatment decreased PMA1 expression, pHc, and vacuolar pH, whereas activation of TORC1 signaling by expressing constitutively active GTR1 (GTR1Q65L) resulted in the opposite phenotypes. Deletion of SIR2 or expression of a phospho‐mutant form of SIR2 increased PMA1 expression, pHc, and vacuolar pH in the tor1Δ mutant, suggesting a functional interaction between Sir2 and TORC1 signaling. Furthermore, deletion of TOR1 or KNS1 encoding a LAMMER kinase decreased the phosphorylation level of Sir2, suggesting that TORC1 signaling controls Sir2 phosphorylation. It was also found that Sit4, a protein phosphatase 2A (PP2A)‐like phosphatase, and Kns1 are required for TORC1 signaling to regulate PMA1 expression and that TORC1 signaling and the cyclic AMP (cAMP)/protein kinase A (PKA) pathway converge on CK2 to regulate PMA1 expression through Sir2. Taken together, these findings suggest that TORC1 signaling regulates PMA1 expression and pHc through the CK2–Sir2 axis, which is also controlled by cAMP/PKA signaling in yeast.  相似文献   
95.
96.

Propagation of gametophytes and sporophytes using mechanical fragmentation has been considered a suitable method for mass production of ferns. This study aimed to develop a practical propagation method for Lemmaphyllum microphyllum C. Presl, which is a fern of significant ornamental and medicinal value. Gametophytes were obtained through in vitro spore germination and used for propagation experiments. The gametophyte was mechanically fragmented using a scalpel into small fragments, which were then used to investigate gametophyte proliferation. In addition, the gametophyte was fragmented using a blender and then used to study sporophyte formation. Optimal proliferation conditions of the gametophyte were determined using Murashige and Skoog (MS) basal medium (double-, full-, half-, quarter-strength), Knop medium, and medium components (sucrose, nitrogen sources, activated charcoal), at various concentrations. The fresh weight of the gametophyte was 14-fold higher than that of gametophytes (300 mg) used as culture material, when cultured on double-strength MS. Moreover, 1 g of the gametophyte fragmented in 25 mL of distilled water formed more than 430 sporophytes in a soil mixture in an area of 7.5 cm2. The sporophytes were successfully cultivated in the greenhouse after acclimation. A large-scale production method for L. microphyllum that can be easily implemented in a fern production farm is outlined.

  相似文献   
97.
Antimicrobial peptides are class of small, positively charged peptides known for their broad‐spectrum antimicrobial activity. Antimicrobial activities for most antimicrobial peptides have largely remained elusive, particularly in the lactic acid bacteria. However, recently our investigation using LPcin‐YK3, an antimicrobial peptide from bovine milk, suggests that in vitro antimicrobial activity was reduced over 100‐fold compared with pathogenic bacteria. Additionally, for the structural study of how antimicrobial peptide undergoes its reaction at the proteolytic pathway of lactic acid bacteria based on degradation assay and propidium iodide staining, we performed molecular docking for interaction between oligopeptide‐binding protein A and LPcin‐YK3 peptide. Given that degradation related to the LPcin‐YK3 peptide in lactic acid bacteria proteolytic system, the inhibitory inactivity of LPcin‐YK3 against beneficial lactic acid bacteria strains may be one of the primary pharmacological properties of recombinant peptide discovered in bovine milk. These results provide structural and functional insights into the proteolytic mechanism and possibility as a putative substrate of oligopeptide‐binding protein A in respect of LPcin‐YK3 peptide.  相似文献   
98.
Biomolecules, especially proteins and nucleic acids, have been widely studied to develop biochips for various applications in scientific fields ranging from bioelectronics to stem cell research. However, restrictions exist due to the inherent characteristics of biomolecules, such as instability and the constraint of granting the functionality to the biochip. Introduction of functional nanomaterials, recently being researched and developed, to biomolecules have been widely researched to develop the nanobiohybrid materials because such materials have the potential to enhance and extend the function of biomolecules on a biochip. The potential for applying nanobiohybrid materials is especially high in the field of bioelectronics. Research in bioelectronics is aimed at realizing electronic functions using the inherent properties of biomolecules. To achieve this, various biomolecules possessing unique properties have been combined with novel nanomaterials to develop bioelectronic devices such as highly sensitive electrochemical‐based bioelectronic sensing platforms, logic gates, and biocomputing systems. In this review, recently reported bioelectronic devices based on nanobiohybrid materials are discussed. The authors believe that this review will suggest innovative and creative directions to develop the next generation of multifunctional bioelectronic devices.  相似文献   
99.
On‐site predetection of pathogens could significantly decrease of a disease outbreak or national loss in most of the countries. However, conventional detection techniques are limited in use for on‐site detection due to the necessity of specialized skill or equipment. Therefore, it is necessary to develop a new technique that can predetect pathogens in the field without special skills or equipment. Here, a DNAzyme strategy to control a plasmonic biosensor for rapid and simple visual detection of Salmonella choleraesuis is adopted. Multicomponent DNAzyme formed by target addition can cleave the linker effectively at 50 °C. Linker cleavage induces dispersion of two DNA‐immobilized gold nanoparticles and color change. Under optimized assay conditions, the target could be detected via visual discrimination sensitively and specifically. Moreover, the biosensor shows the possibility of practical use with contaminants and a 16S rRNA real target. As a result, the proposed plasmonic biosensor can visually detect S. choleraesuis without unstable enzymes, a specialized technique, or equipment. Therefore, these advantages could allow that this biosensor would be used for on‐site predetection to lower the risk of transmission of infectious diseases.  相似文献   
100.
Wetlands Ecology and Management - Small valley topology on terraced uplands is a unique groundwater-dependent ecosystem in East Asia. Traditionally, this characteristic valley topology has been...  相似文献   
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