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611.
María C. Díaz Andrade Ana C. Moya Anahí Wehitt Edgardo E. Di Giácomo Elena J. Galíndez 《Journal of fish biology》2018,93(2):424-427
The presence of follicular cellular processes (FCP) that cross the zona pellucida, has been recorded in the ovarian follicles of Callorhinchus callorhynchus. This constitutes the first report describing the presence of these structures in a species of the Holocephali. Considering that FCPs have only previously been reported in the Selachii, these findings suggest that FCPs could have been lost by the Batoidea after their divergence, around 280 M B.P. 相似文献
612.
Enhanced isobutanol production from acetate by combinatorial overexpression of acetyl‐CoA synthetase and anaplerotic enzymes in engineered Escherichia coli 下载免费PDF全文
613.
Genetic diversity in two species of Impatiens in Korea was investigated using starch gel electrophoresis. Impatiens hypophylla is a rare species endemic to southwestern Japan and southeastern Korea, whereas I. rextori is widespread in East Asia. Impatiens textori has considerably higher genetic diversity than I. hypophylla . For example, mean values of genetic diversity within populations (He) of I. textori and I. hypophylla were 0.206 and 0.102, respectively. The high outcrossing rate (mean 1 = 0.89), abundance and widespread distribution, and large population size may be factors responsible for the maintenance of high levels of genetic variation in I. textori . Analyss of fixation indices indicated that considerable population substructuring within populations of I. hypophylla , partly resulting from inbreeding and/or genetic drift in small populations coupled with limited gene flow (mean FIS = 0.699). However, the degree of population divergence observed in I. hypophylla (mean GST = 0.059) was considerably lower than that in other plants with similar life history traits. It is supposed that similar selection at populations of I. hypophylla examined might maintain similar gene frequencies in isolated populations. 相似文献
614.
Myung Kyum Kim Eun Tae Kim Sang Bum Kim Ha Yeon Jeong Beom Young Park Sathiyaraj Srinivasan 《Journal of microbiology (Seoul, Korea)》2018,56(1):36-41
Gram-staining-positive, motile, rod-shaped bacteria, designated as H31022T and H31024 was isolated from rumen contents of a Holstein cow. Optimum growth occurred at 25°C and pH 7.0 on R2A agar medium. Oxidase and catalase activities are positive. The 16S rRNA gene sequence (1,452 bp) of the new isolates revealed they belong to the genus Kurthia of the phylum Firmicutes. Highest gene sequence similarities were assessed to be with Kurthia massiliensis JC30T (98.4%), Kurthia senegalensis JC8ET (97.5%), and Kurthia populi 10y-14T (97.4%). Kurthia sibirica DSM 4747T (97.3%), Kurthia zopfii NBRC 101529T (97.0%), and Kurthia gibsonii NCIMB 9758T (96.7%). DNA G + C content of strains H31022T and H31024 were 34.4% and 39.7%. Strains H31022T and H31024 has the following chemotaxonomic characteristics; the major fatty acids are iso-C15:0, iso-C14:0 and anteiso-C15; polar lipid profile contained diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), unknown aminophospholipids (APL), unknown glycolipids (GL), unknown phospholipids (PL), and unknown polar lipids (L); the major quinone is MK-7. Based on polyphasic taxonomic analysis, strains H31022T (= KCTC 33923T = JCM 19640T) and H31024 (= KCTC 33924T = JCM 19641T) identified a novel species in the genus Kurthia for which the name Kurthia ruminicola sp. nov. is proposed. 相似文献
615.
Md. Faisal Kabir Jae-Kook Lee Mun Gi Jeong Mwamula Abraham Okki Yong-Hwa Choi Dong Woon Lee 《Journal of Asia》2018,21(1):69-74
Heterodera schachtii is a well-known, destructive pathogen of Chinese cabbage (Brassica rapa pekinensis) in Korea, and several studies have attempted to find a potential control measure against it. This study is the first to investigate the effects of varying temperature on the reproduction and damage potential of H. schachtii to Chinese cabbage. Chinese cabbage plants were inoculated with H. schachtii at different densities (1, 2, or 4 juveniles per gram of soil) and grown under three temperature regimes: constant (15, 20, or 25 °C), increasing (10, 14, and 18 °C), and fluctuating (positive, 16.7–22.0 °C; negative, 21.5–11.5 °C). At a constant temperature after 30 days of inoculation, both Chinese cabbage and H. schachtii performed best at 20 °C. However, after 60 days of inoculation, H. schachtii had a significantly higher population at 20 °C, whereas cabbage growth was best at 25 °C. With increasing temperature, the numbers of cysts and females did not change significantly, and reached maxima at an initial temperature of 14 °C. However, the number of leaves and weights of the Chinese cabbage plants significantly differed at 14 °C. Under fluctuating temperatures, temperature decreases reduced the H. schachtii population. 相似文献
616.
Jae Woo Han Gyung Ja Choi Beom Seok Kim 《World journal of microbiology & biotechnology》2018,34(11):163
Aromatic polyketides are secondary metabolites widely found in bacteria, fungi, and plants, which are well-known for their diverse chemical structures and biological functions. The structural diversity of aromatic polyketides arises from a series of enzymatic modifications of the linear poly-β-ketone intermediates during biosynthesis. Their versatile bioactivities are exemplified by reports of their use as antibacterials, antifungals, antivirals, and antiparasitics. Despite many reports on the antimicrobial nature of aromatic polyketides, their potential use as plant disease control agents has still not been systematically explored and discussed. This review highlights examples of the use of aromatic polyketides as plant disease control agents and discusses their function and merits as agrochemicals. 相似文献
617.
Optimized Concentration of Redox Mediator and Surface Protection of Li Metal for Maintenance of High Energy Efficiency in Li–O2 Batteries 下载免费PDF全文
Recently, various approaches for adding redox mediators to electrolytes and introducing protective layers onto Li metal have been suggested to overcome the low energy efficiency and poor cycle life of Li–O2 batteries. However, the catalytic effect of the redox mediator for oxygen evolution gradually deteriorates during repeated cycling owing to its decomposition at the surfaces of both the oxygen electrode (cathode) and the Li metal electrode (anode). Here, optimized Li–O2 batteries are designed with a continuously effective redox mediator and a stable protective layer for the Li metal electrode by optimizing the LiBr concentration and introducing a graphene–polydopamine composite layer, respectively. These synergistic modifications lead to a reduction of the charge potential to below 3.4 V and significantly improve the stability and cycle life of Li–O2 batteries. Consequently, a high energy efficiency of above 80% is maintained over 150 cycles. Herein, it is confirmed that the relationships between all the battery materials should be understood in order to improve the performance of Li–O2 batteries. 相似文献
618.
Song Hyeon Gi Byeon Seon Yeong Chung Goo Yong Jung Sang-Myung Choi Jung Il Shin Hwa Sung 《Bioprocess and biosystems engineering》2018,41(9):1295-1303
Bioprocess and Biosystems Engineering - Microalgal carotenoids are attractive health ingredients, but their production should be optimized to improve cost-effectiveness. Understanding cellular... 相似文献
619.
Ki Beom Park Jong Yul Roh Seong Yoon Kim Nam‐Yeon Kim Yong Hun Jo Rae‐Dong Jeong Wook‐Gyo Lee Hee‐Il Lee Shin‐Hyeong Cho Yong Seok Lee Yeon Soo Han 《Entomological Research》2021,51(1):3-11
The Asian longhorned tick, Haemaphysalis longicornis, is widely distributed in China, Japan, and Korea and may transmit infectious diseases. Severe fever with thrombocytopenia syndrome (SFTS) is an important tick‐borne disease caused by the SFTS virus (SFTSV). Deep sequencing to confirm the presence of SFTSV in ticks has not been reported in Korea. To detect SFTSV, RNA was extracted from tick samples and analyzed using high‐throughput deep sequencing. Based on BLASTN results, numerous SFTSV reads were identified. Moreover, a nearly complete genome of SFTSV (JNU‐1 isolate) was obtained using Sanger sequencing. The genome of the JNU‐1 isolate includes three segments of 6,286, 3,299 and 1,642 nucleotides (nt) termed large (L), medium (M), and small (S), respectively. Also, phylogenetic and recombination analyses for each segment of SFTSV were performed using the JNU‐1 isolate. The three segments of JNU‐1 isolate were closely related to the genotype B known human‐derived Korean SFTSV isolate; the JNU‐1 isolate showed no recombination sites with other isolates. This study is the first report of detection of SFTSV from ticks using deep sequencing in Korea and provides information on the genetic diversity of SFTSV in East Asia. 相似文献
620.
Kim BK Kim SU Kim HS Park JY Ahn SH Chon CY Cho IR Joh DH Park YN Han KH Kim do Y 《PloS one》2012,7(4):e35825