• Title/Summary/Keyword: Recent Research

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Fibrolytic Rumen Bacteria: Their Ecology and Functions

  • Koike, Satoshi;Kobayashi, Yasuo
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.131-138
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    • 2009
  • Among rumen microbes, bacteria play important roles in the biological degradation of plant fiber due to their large biomass and high activity. To maximize the utilization of fiber components such as cellulose and hemicellulose by ruminant animals, the ecology and functions of rumen bacteria should be understood in detail. Recent genome sequencing analyses of representative fibrolytic bacterial species revealed that the number and variety of enzymes for plant fiber digestion clearly differ between Fibrobacter succinogenes and Ruminococcus flavefaciens. Therefore, the mechanism of plant fiber digestion is also thought to differ between these two species. Ecology of individual fibrolytic bacterial species has been investigated using pure cultures and electron microscopy. Recent advances in molecular biology techniques complement the disadvantages of conventional techniques and allow accurate evaluation of the ecology of specific bacteria in mixed culture, even in situ and in vivo. Molecular monitoring of fibrolytic bacterial species in the rumen indicated the predominance of F. succinogenes. Nutritive interactions between fibrolytic and non-fibrolytic bacteria are important in maintaining and promoting fibrolytic activity, mainly in terms of crossfeeding of metabolites. Recent 16S rDNA-based analyses suggest that presently recognized fibrolytic species such as F. succinogenes and two Ruminococcus species with fibrolytic activity may represent only a small proportion of the total fibrolytic population and that uncultured bacteria may be responsible for fiber digestion in the rumen. Therefore, characterization of these unidentified bacteria is important to fully understand the physiology and ecology of fiber digestion. To achieve this, a combination of conventional and modern techniques could be useful.

Carbon Fibers(III): Recent Technical and Patent Trends

  • Seo, Min-Kang;Park, Sang-Hee;Kang, Shin-Jae;Park, Soo-Jin
    • Carbon letters
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    • v.10 no.1
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    • pp.43-51
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    • 2009
  • Carbon fibers are a new breed of high-strength materials. The existence of carbon fiber came into being in 1879 when Edison took out a patent for the manufacture of carbon filaments suitable for use in electric lamps. However, it was in the early 1960s when successful commercial production was started, as the requirements of the aerospace industry for better and lightweight materials became of paramount importance. In recent decades, carbon fibers have found wide applications in commercial and civilian aircraft, along with recreational, industrial, and transportation markets as the price of carbon fiber has come down and technologies have matured. The market for carbon fiber has experienced a good growth in recent years. The growth rate for the last 23years was about 12%. The article reviewed 9,641 Korea, U.S., Japan, Europe patents issued in the carbon fibers in order to offer additional insight for researchers and companies seeking to navigate carbon fiber patent landscape. This article will provide you with all the valuable information and tools you will need to investigate your study successfully within the carbon fiber field. This article also will save you hundreds of hours of your own personal research time and will significantly benefit you in expanding your business in the carbon fiber market.

Recent research progress on the functional roles and regulatory mechanisms of SMALL AUXIN UP RNA gene family (SMALL AUXIN UP RNA 유전자 집단의 기능과 조절 메커니즘에 대한 최근 연구 동향)

  • Lee, Sang Ho
    • Journal of Plant Biotechnology
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    • v.45 no.3
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    • pp.183-189
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    • 2018
  • The plant hormone auxin regulates the overall metabolic processes essential for plant growth and development. Auxin signaling is mediated by early auxin response genes, which are classified into three major families: AUXIN/INDOLE ACETIC ACID (AUX/IAA), GRETCHEN HAGEN3 (GH3) and SMALL AUIN UP RNA (SAUR). The SAUR gene family is the largest family among early auxin response genes and encodes the small and highly unstable gene products. The functional roles of SAUR genes have remained unclear for many years. The traditional genetic and molecular studies on the SAUR functions have been hampered by their likely genetic redundancy and tandem arrays of highly related genes in the plant genome, together with the molecular characteristics of SAUR. However, recent studies have suggested possible roles of SAUR in a variety of tissues and developmental stages in accordance with the novel approaches such as gain-of-function and RNA silencing techniques. In this review, the recent research progress on the functional roles and regulatory mechanisms of SAUR and a set of possible future works are discussed.

Recent Brazilian research on thunderstorm winds and their effects on structural design

  • Riera, Jorge D.;Ponte, Jacinto Jr.
    • Wind and Structures
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    • v.15 no.2
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    • pp.111-129
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    • 2012
  • Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by sypnoptic events. Wind effects due to other phenomena, such as thunderstorm downbursts, are simply neglected. In this paper, results of recent and ongoing research on this topic in Brazil are presented. The model of the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS), proposed by Ponte and Riera for engineering applications, is first described. This model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters are related to meteorological variables, which are susceptible of statistical assessment. An application of the model in the simulation of the wind climate in a region sujected to both EPS and TS winds is discussed next. It is shown that, once the relevant meteorological variables are known, the simulation of the wind excitation for purposes of design of transmission lines, long-span crossings and similar structures is feasible. Complementing the theoretical studies, wind velocity records during a recent TS event in southern Brazil are presented and preliminary conclusions on the validity of the proposed models discussed.

Recent Research Trends of Hataedock (하태독법의 최신 연구 동향)

  • Ju, Hyun Ju;Cheon, Jin Hong;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.34 no.4
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    • pp.31-42
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    • 2020
  • Objectives The purpose of this study is to perform a review on recent researches of Hataedock, a traditional method of removing fetal toxin by dropping herbal extracts in the mouth, to appraise its preventive and therapeutic effects of diseases. Methods Studies of Hataedock were extracted from both Chinese and Korean medical journals published within 10 years, from January 2010 to January 2020. Clinical studies and experimental researches were analyzed and categorized to skin disease, allergic rhinitis, intestinal mucosa inflammation and anal fistula for further evaluation. Results Among 194 studies were searched and screened, 22 met designated criteria. Hataedock showed the effectiveness in treating skin disease, allergic rhinitis, intestinal mucosa inflammation and anal fistula by maintaining skin barrier and regulating immune system. Coptis japonica, Glycyrrhiza uralensis, and Fermented Glycine max were mainly used as herbal extracts in Hataedock. Conclusion This study shows the recent research trends of Hataedock and suggests that Hataedock can be considered as a method of treatment or prevention to some of the incurable chronic diseases.

Auxin-responsive SMALL AUXIN UP RNA genes : recent research progress and its application for crop improvement (옥신 반응 SMALL AUXIN UP RNA 유전자의 최근 연구 동향 및 작물 개량을 위한 적용)

  • Lee, Sang Ho
    • Journal of Plant Biotechnology
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    • v.40 no.2
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    • pp.59-64
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    • 2013
  • Auxin is a key plant hormone which regulates overall plant growth development. A number of researches to investigate auxin signaling identified three major classes of early auxin response genes: AUX/IAA, GH3 and SMALL AUXIN UP RNA (SAUR). Among these genes, in planta functions of SAUR gene family are largely ambiguous, while both AUX/IAA and GH3 genes are analyzed to mediate negative feedback on auxin response. SAUR genes encode small plant-specific proteins. SAUR gene products are highly unstable and transiently expressed in the tissue- and developmental-specific manners in response to auxin and various environmental stimuli. In the decades, molecular and genetic approaches to elucidate in planta functions of SAURs have been hampered by several factors such as the unstable molecular features and functional redundancy among them. However, a series of recent studies focusing on several subgroups of SAUR gene family made significant progress in our understanding of its biochemical and physiological functions. These works suggest that many SAUR proteins mainly regulate auxin-related cell expansion and auxin transport. In this review, the recent progress in SAUR research and prospects for crop improvement through its genetic manipulation are discussed.

Causes and suggestions on administrative measures of Subsidence (sink holes) in Urban areas (도심지역의 지반침하(싱크홀)의 원인과 관리적 대책에 대한 제언)

  • Kim, Chun-Soo;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.18 no.4
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    • pp.1-9
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    • 2016
  • In recent years, urban areas occurred several times a sinkhole. In Korea, this limestone area where the sink hole sink holes occur based on not much was seen as a very rare phenomenon. However, the occurrence of accidents in recent Subsidence and urban areas is occurring in the limestone sinkhole may yet see another one called artificial Subsidence phenomenon. Subsidence in urban areas can have various causes, such as depression groundwater level changes due to the influence of soil, underground, etc. underground utilities by anthropogenic actions. But a lot of research on natural sinkhole by geological experts continued steadily since the past Subsidence that occurred in recent years the city has become an urgent problem to formulate a countermeasure to be very concerned about the human and material damage. In this study, the city by analyzing existing research on the causes and countermeasures of Subsidence recently released look at the announced sinkhole, published statistics and cases of Subsidence data, and overseas corresponding practices in each relevant agencies and to suggest measures for local Subsidence.

Recent Research Progress on Eco-Friendly Perovskite Solar Cells (친환경 페로브스카이트 태양전지 최신 기술 동향)

  • You, Hyung Ryul;Choi, Jongmin
    • Journal of the Korean Electrochemical Society
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    • v.22 no.3
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    • pp.104-111
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    • 2019
  • Metal halide perovskite materials are considered as promising semiconducting materials for next-generation solar cells due to their unique electrical and optical properties. Intensive progress in perovskite solar cell yielded a certified power conversion efficiency over 24%. However, most of highly efficient perovskite solar cells required Pb-based perovskite materials, which is a critical obstacle for their commercialization, and development of Pb-free perovskite materials is one of recent urgent issues in this field. In this paper, we will introduce recent research progress on Pb-free perovskite solar cells.

Finding Needles in a Haystack with Light: Resolving the Microcircuitry of the Brain with Fluorescence Microscopy

  • Rah, Jong-Cheol;Choi, Joon Ho
    • Molecules and Cells
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    • v.45 no.2
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    • pp.84-92
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    • 2022
  • To understand the microcircuitry of the brain, the anatomical and functional connectivity among neurons must be resolved. One of the technical hurdles to achieving this goal is that the anatomical connections, or synapses, are often smaller than the diffraction limit of light and thus are difficult to resolve by conventional microscopy, while the microcircuitry of the brain is on the scale of 1 mm or larger. To date, the gold standard method for microcircuit reconstruction has been electron microscopy (EM). However, despite its rapid development, EM has clear shortcomings as a method for microcircuit reconstruction. The greatest weakness of this method is arguably its incompatibility with functional and molecular analysis. Fluorescence microscopy, on the other hand, is readily compatible with numerous physiological and molecular analyses. We believe that recent advances in various fluorescence microscopy techniques offer a new possibility for reliable synapse detection in large volumes of neural circuits. In this minireview, we summarize recent advances in fluorescence-based microcircuit reconstruction. In the same vein as these studies, we introduce our recent efforts to analyze the long-range connectivity among brain areas and the subcellular distribution of synapses of interest in relatively large volumes of cortical tissue with array tomography and superresolution microscopy.

Review of Statistical Methods for Evaluating the Performance of Survival or Other Time-to-Event Prediction Models (from Conventional to Deep Learning Approaches)

  • Seo Young Park;Ji Eun Park;Hyungjin Kim;Seong Ho Park
    • Korean Journal of Radiology
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    • v.22 no.10
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    • pp.1697-1707
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    • 2021
  • The recent introduction of various high-dimensional modeling methods, such as radiomics and deep learning, has created a much greater diversity in modeling approaches for survival prediction (or, more generally, time-to-event prediction). The newness of the recent modeling approaches and unfamiliarity with the model outputs may confuse some researchers and practitioners about the evaluation of the performance of such models. Methodological literacy to critically appraise the performance evaluation of the models and, ideally, the ability to conduct such an evaluation would be needed for those who want to develop models or apply them in practice. This article intends to provide intuitive, conceptual, and practical explanations of the statistical methods for evaluating the performance of survival prediction models with minimal usage of mathematical descriptions. It covers from conventional to deep learning methods, and emphasis has been placed on recent modeling approaches. This review article includes straightforward explanations of C indices (Harrell's C index, etc.), time-dependent receiver operating characteristic curve analysis, calibration plot, other methods for evaluating the calibration performance, and Brier score.