• 제목/요약/키워드: Science and Technology (S&T)

검색결과 3,173건 처리시간 0.031초

Comparison of Single and Blend Acidifiers as Alternative to Antibiotics on Growth Performance, Fecal Microflora, and Humoral Immunity in Weaned Piglets

  • Ahmed, S.T.;Hwang, J.A.;Hoon, J.;Mun, H.S.;Yang, C.J.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제27권1호
    • /
    • pp.93-100
    • /
    • 2014
  • The banning of the use of antibiotics as feed additive has accelerated investigations of alternative feed additives in animal production. This experiment investigated the effect of pure citric acid or acidifier blend supplementation as substitute for antibiotic growth promoters on growth performance, fecal microbial count, and humoral immunity in weaned piglets challenged with Salmonella enterica serover Typhimurium and Escherichia coli KCTC 2571. A total of 60 newly weaned piglets (crossbred, 28-d-old; average 8 kg initial weight) were randomly assigned to four dietary treatments in a completely randomized design. Dietary treatments included NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.5% pure citric acid), and T2 (basal diet+0.4% acidifier blend). All piglets were orally challenged with 5 mL of culture fluid containing $2.3{\times}10^8$ cfu/mL of E. coli KCTC 2571 and $5.9{\times}10^8$ cfu/mL of S. typhimurium at the beginning of the experiment. The PC group showed the highest ADG and ADFI, whereas gain:feed was improved in the PC and T1 group (p<0.05). All dietary treatments showed significant reduction in fecal counts of Salmonella and E. coli, compared to NC (p<0.05), with PC being better than T1 and T2. Significant elevation in fecal Lactobacillus spp. counts was shown by treatments with T1, T2, and PC, whereas Bacillus spp. counts were increased by treatment with T1 and T2 compared to NC and PC diet (p<0.05). Serum IgG concentration was increased by T1 diet (p<0.05), whereas IgM and IgA were not significantly affected by any of the dietary treatments (p>0.05). From these above results, it can be concluded that, as alternatives to antibiotics dietary acidification with pure citric acid or acidifiers blend did not fully ameliorate the negative effects of microbial challenges in respect of growth performance and microbial environment, however improved immunity suggested further research with different dose levels.

SOME CONSIDERATIONS ABOUT UPPER BOUNDS ON THE SUM OF SQUARES OF DEGREES

  • Kim, Hwa-Joon;Supratid, S.;Kitbmrungrat, K.;Liemmance, W.;Julraksa, N.
    • Journal of applied mathematics & informatics
    • /
    • 제27권3_4호
    • /
    • pp.865-873
    • /
    • 2009
  • Goodman([3]) presented the question of finding a best possible upper bound of the form $t(G)\;+\;t(G^c)$, where t(G) denote the number of triangles in given graph G. In this, the form of squares of degrees is appeared and many researches have been pursued as an application related to this. Here, we would like to deal with corollary related to the results of Nikiforov([6]).

  • PDF

The Complete Mitochondrial Genome of the Fourhorn Sculpin Triglopsis quadricornis (Perciformes, Cottidae) from Sirius Passet, North Greenland

  • Kim, Bo-Mi;Kihm, Ji-Hoon;Park, Tae-Yoon S.
    • Ocean and Polar Research
    • /
    • 제43권4호
    • /
    • pp.371-374
    • /
    • 2021
  • Triglopsis quadricornis Linnaeus, 1758 (Cottidae) is distributed in the Atlantic and Arctic and has four unique bony protuberances on its head. Here, we report the complete, circular, and annotated mitochondrial genome of T. quadricornis. The complete T. quadricornis mitochondrion was sequenced by high-throughput Illumina HiSeq platform. The sequences are 16,736 bp in size and contains 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, a control region, and large and small ribosomal subunits. The overall genomic structure of T. quadricornis mitochondrion was conserved with the gene arrangement of Megalocottus and Myoxocephalus species, and phylogenetic analysis supports their sister relationships. Most PCGs consist of TAA or TAG as a termination codon, whereas COII, ND4, and CYTB have T-- as a stop codon. This complete mitochondrial DNA information of T. quadricornis will provide an essential genomic resource to elucidate the phylogenetic relationship and evolutionary history of the family Cottidae.

Effect of Fasting and Refeeding on Growth and Blood Chemistry in Juvenile Olive Flounder Paralichthys olivaceus L.

  • 조성환
    • 한국양식학회지
    • /
    • 제22권1호
    • /
    • pp.11-15
    • /
    • 2009
  • Effect of fasting and refeeding on growth and blood chemistry of juvenile olive flounder Paralichthys olivaceus L. was investigated when fish achieved compensatory growth. Fish were fed the experimental diet for 6 days a week. Five treatments in triplicate were prepared: C, S1, S2, S3 and S4. Fish in the control group (C) were hand-fed to apparent satiation twice a day. Fish in treatments of S1, S2, S3 and S4 experienced 1, 2, 3 and 4 weeks of starvation and were then hand-fed to satiation twice daily during the remaining 7, 6, 5 and 4 weeks of the experiment, respectively. Weight gain of fish in C, S1 and S2 were higher than those of fish in S3 and S4. A significant difference in plasma total protein, glucose, triglyceride, $T_3$ and $T_4$ was observed in between starved and refed fish for the rest periods of the feeding trial. Plasma total protein and $T_3$ of flounder decreased with week of fasting and following correlationships were obtained; Y (Total protein) = -0.13X (week of fasting) + 1.54, $R^2=0.9792$ and $Y(T_3)=-11.48X$ (week of fasting) + 79.57, $R^2=0.8822$, respectively.

Purification and Characterization of Streptomyces griseus Trypsin Overexpressed in Streptomyces lividans

  • KOO, BON-JOON;KWANG HEE BAE;SI-MYONG BYUN;SOON-KWANG HONG
    • Journal of Microbiology and Biotechnology
    • /
    • 제8권4호
    • /
    • pp.333-340
    • /
    • 1998
  • Streptomyces griseus trypsin (SGT) is an extracellular proteinase produced by S. griseus. The sprT gene, which encodes premature SGT protein, was cloned into the plasmid pWHM3, a Streptomyces-E. coli shuttle vector. When the recombinant plasmid was introduced into Streptomyces lividans TK24, two proteins with molecular weights of 28 kDa and 42 kDa were detected. The 28-kDa protein was a SGT protein while the larger 42-kDa protein is thought to have been a premature form of the SGT protein. The SGT protein was purified to homogeneity via ammonium sulfate fractionation and many column chromatographies, including CM -sepharose chromatography, Mono-S chromatography, and Superose-12 chromatography, from the culture broth of S. lividans TK24 harboring the sprT gene. The N-terminal amino acid sequence, isoelectric points, and stabilities at various conditions of the SGT proteins purified from the Pronase and transformant were almost identical. The amount of the expressed SGT in S. lividans TK 24 was determined to be 5 times more than that of S. griseus based on the enzymatic activity against artificial substrate.

  • PDF

새로운 과학기술정책 패러다임 모색과 정책방향: 양에서 질적 발전으로

  • 채영복;조현대
    • 기술혁신연구
    • /
    • 제10권1호
    • /
    • pp.1-21
    • /
    • 2002
  • This paper suggests a new paradigm of science and technology (S&T) policy for the purpose of the new national development that pursues not the scale expansion of a industrial production but the qualitative enhancement of industrial and S&T comparativeness. The new S&T policy paradigm includes new policy directions such as the density increasement of high quality- brain power and the energy supply for crossing the threshold from imitative R&D to creative R&D. Also, this paper argues that it is necessary not only to acquire the support of the local S&T community and policy-makers on the new S&T policy paradigm, but also to develop and implement policy measures in details on the basis of the new paradigm suggested by the paper.

  • PDF

EPMA quantification on the chemical composition of retained austenite in a Fe-Mn-Si-C-based multi-phase steel

  • Yoon‑Uk Heo;Chang‑Gon Jeong;Soo‑Hyun Kim;Gun‑Young Yoon;T. T. T. Trang;Youngyun Woo;Eun Yoo Yoon;Young‑Seon Lee
    • Applied Microscopy
    • /
    • 제52권
    • /
    • pp.14.1-14.10
    • /
    • 2022
  • An electron probe X-ray microanalyzer (EPMA) is an essential tool for studying chemical composition distribution in the microstructure. Quantifying chemical composition using standard specimens is commonly used to determine the composition of individual phases. However, the local difference in chemical composition in the standard specimens brings the deviation of the quantified composition from the actual one. This study introduces how to overcome the error of quantification in EPMA in the practical aspect. The obtained results are applied to evaluate the chemical com position of retained austenite in multi-phase steel. Film-type austenite shows higher carbon content than blocky-type one. The measured carbon contents of the retained austenite show good coherency with the calculated value from the X-ray diffraction.

Application of Vector Moving Preisach Model to Longitudinal Thin Film Media

  • S. C. Seol;T. Kang;K. H. Shin;Lee, T. D.;Park, G. S.
    • Journal of Magnetics
    • /
    • 제2권3호
    • /
    • pp.101-104
    • /
    • 1997
  • Vector Moving Preisach model has been applied to the unoriented Co-based alloy thin film media. In the model, the out-of plane easy axis distribution of the particles was derived directly from the texture coefficient phkl obtained from XRD analysis, which corresponds to the fraction of the grains that have the {hkl} plane lying parallel to in-plane direction. The model was validated, by its prediction of a variety of responses, including major loop, minor loop, and the angular dependence of coercivities.

  • PDF

SD-WAN 기반의 사용자 중심 가상 전용 네트워크 시스템 설계 및 구현 (Design and Implementation of User-Oriented Virtual Dedicate Network System Based on Software-Defined Wide Area Network)

  • 김용환;김동균
    • 한국통신학회논문지
    • /
    • 제41권9호
    • /
    • pp.1081-1094
    • /
    • 2016
  • KREONET은 한국과학기술정보연구원(KISTI)이 관리 운영하는 국가 R&D 연구망이다. 이는 고성능 네트워크 인프라를 기반으로 산 학 연 등 약 200여 기관을 대상으로 첨단 응용 네트워크 서비스를 지원하고 있다. 하지만 KREONET은 하드웨어 기반의 폐쇄적인 환경에 의하여 제약을 받고 있어 최근 네트워크 환경의 변화에 따른 새로운 네트워크 서비스에 대한 첨단 응용 사용자들의 다양한 요구사항을 반영하는데 한계점을 지닌다. 이에 따라, KISTI는 첨단연구 및 협업의 적시성 환경 및 프로그래머블 네트워크 인프라를 구축하고 이에 기반한 새로운 첨단응용 서비스를 지원하기 위하여 KREONET-S 프로젝트를 출범하였다. 본 논문에서는 KREONET-S 시스템 구조 및 이의 데이터/제어 평면의 네트워크 인프라 구축 현황을 제시하고, 이에 기반하여 첨단 응용 연구자들이 필요로 하는 가상 전용 네트워크를 동적 구축하는 VDN (Virtual Dedicate Network) 서비스에 관하여 설명한다. 또한 KREONET-S 환경에 VDN 애플리케이션을 구현하고 이의 성능 분석을 수행함으로써 KREONET-S 시스템이 새로운 네트워크 패러다임의 변화에 대응하는 훌륭한 방안임을 검증한다.

Message Security Level Integration with IoTES: A Design Dependent Encryption Selection Model for IoT Devices

  • Saleh, Matasem;Jhanjhi, NZ;Abdullah, Azween;Saher, Raazia
    • International Journal of Computer Science & Network Security
    • /
    • 제22권8호
    • /
    • pp.328-342
    • /
    • 2022
  • The Internet of Things (IoT) is a technology that offers lucrative services in various industries to facilitate human communities. Important information on people and their surroundings has been gathered to ensure the availability of these services. This data is vulnerable to cybersecurity since it is sent over the internet and kept in third-party databases. Implementation of data encryption is an integral approach for IoT device designers to protect IoT data. For a variety of reasons, IoT device designers have been unable to discover appropriate encryption to use. The static support provided by research and concerned organizations to assist designers in picking appropriate encryption costs a significant amount of time and effort. IoTES is a web app that uses machine language to address a lack of support from researchers and organizations, as ML has been shown to improve data-driven human decision-making. IoTES still has some weaknesses, which are highlighted in this research. To improve the support, these shortcomings must be addressed. This study proposes the "IoTES with Security" model by adding support for the security level provided by the encryption algorithm to the traditional IoTES model. We evaluated our technique for encryption algorithms with available security levels and compared the accuracy of our model with traditional IoTES. Our model improves IoTES by helping users make security-oriented decisions while choosing the appropriate algorithm for their IoT data.