RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
        • 등재정보
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        Antibacterial, Anti-Diarrhoeal, Analgesic, Cytotoxic Activities, and GC-MS Profiling of Sonneratia apetala (Buch.-Ham.) Seed

        Sheikh Julfikar Hossain,M Rabiul Islam,Tahmina Pervin,M Iftekharuzzaman,Omer A A Hamdi,Sanzida Mubassara,M Saifuzzaman,Jamil Ahmad Shilpi 한국식품영양과학회 2017 Preventive Nutrition and Food Science Vol.22 No.3

        Fruits of Sonneratia apetala (Buch.-Ham.), (English: mangrove apple, Bengali: keora) both seeds and pericarps, are largely consumed as food besides their enormous medicinal application. The fruit seeds have high content of nutrients and bioactive components. The seeds powder of S. apetala was successively fractionated using n-hexane, diethyl ether, chloroform, ethyl acetate, and methanol. The fractions were used to evaluate antibacterial, anti-diarrhoeal, analgesic, and cytotoxic activities. Methanol fraction of seeds (MeS) stronly inhibited Escherichia coli strains, Salmonella Paratyphi A, Salmonella Typhi, Shigella dysenteriae, and Staphylococcus aureus except Vibrio cholerae at 500 μg/disc. All the fractions strongly inhibited castor oil induced diarrhoeal episodes and onset time in mice at 500 mg extract/kg body weight (P<0.001). At the same concentration, MeS had the strongest inhibitory activity on diarrhoeal episodes, whereas the n-hexane fraction (HS) significantly (P<0.05) prolonged diarrhoeal onset time as compared to positive control. Similarly, HS (P<0.005) inhibited acetic acid induced writhing in mice at 500 mg extract/kg, more than any other fraction. HS and diethyl ether fractions of seed strongly increased reaction time of mice in hot plate test at 500 mg extract/kg. All the fractions showed strong cytotoxic effects in brine shrimp lethality tests. Gas chromatography-mass spectrometry analysis of HS led to the identification of 23 compounds. Linoleic acid (29.9%), palmitic acid (23.2%), ascorbyl palmitate (21.2%), and stearic acid (10.5%) were the major compounds in HS. These results suggest that seeds of S. apetala could be of great use as nutraceuticals.

      • SCOPUSKCI등재

        Antibacterial, Anti-Diarrhoeal, Analgesic, Cytotoxic Activities, and GC-MS Profiling of Sonneratia apetala (Buch.-Ham.) Seed

        Hossain, Sheikh Julfikar,Islam, M Rabiul,Pervin, Tahmina,Iftekharuzzaman, M,Hamdi, Omer AA,Mubassara, Sanzida,Saifuzzaman, M,Shilpi, Jamil Ahmad The Korean Society of Food Science and Nutrition 2017 Preventive Nutrition and Food Science Vol.22 No.3

        Fruits of Sonneratia apetala (Buch.-Ham.), (English: mangrove apple, Bengali: keora) both seeds and pericarps, are largely consumed as food besides their enormous medicinal application. The fruit seeds have high content of nutrients and bioactive components. The seeds powder of S. apetala was successively fractionated using n-hexane, diethyl ether, chloroform, ethyl acetate, and methanol. The fractions were used to evaluate antibacterial, anti-diarrhoeal, analgesic, and cytotoxic activities. Methanol fraction of seeds (MeS) stronly inhibited Escherichia coli strains, Salmonella Paratyphi A, Salmonella Typhi, Shigella dysenteriae, and Staphylococcus aureus except Vibrio cholerae at $500{\mu}g/disc$. All the fractions strongly inhibited castor oil induced diarrhoeal episodes and onset time in mice at 500 mg extract/kg body weight (P<0.001). At the same concentration, MeS had the strongest inhibitory activity on diarrhoeal episodes, whereas the n-hexane fraction (HS) significantly (P<0.05) prolonged diarrhoeal onset time as compared to positive control. Similarly, HS (P<0.005) inhibited acetic acid induced writhing in mice at 500 mg extract/kg, more than any other fraction. HS and diethyl ether fractions of seed strongly increased reaction time of mice in hot plate test at 500 mg extract/kg. All the fractions showed strong cytotoxic effects in brine shrimp lethality tests. Gas chromatography-mass spectrometry analysis of HS led to the identification of 23 compounds. Linoleic acid (29.9%), palmitic acid (23.2%), ascorbyl palmitate (21.2%), and stearic acid (10.5%) were the major compounds in HS. These results suggest that seeds of S. apetala could be of great use as nutraceuticals.

      • Exploring the Significance and Interpretation of Animal Motifs in Rock Art: A Systematic Review

        Tie Zhao(Tie Zhao),Daorina(Daorina ),Guofeng Chen(Guofeng Chen),M. Omer(M. Omer ) 아시아사회과학학회 2023 Jornal of Asia Social Science Vol.10 No.1

        Rock art has been a subject of fascination for scholars, archaeologists, and enthusiasts for centuries due to its unique aesthetic qualities and cultural significance. This systematic review paper provides an overview of the significance of rock art motifs and their interpretations. Through a comprehensive analysis of the literature, we identified common rock art motifs and themes, as well as various interpretative approaches and theoretical frameworks used to understand the meanings and contexts of these motifs. The review also explores variations in interpretations across time and space and discusses the implications of these findings for rock art studies. The results reveal that rock art motifs and their interpretations are shaped by diverse cultural, social, and historical contexts, and that interdisciplinary and community-engaged research is needed to better understand, preserve, and appreciate this unique cultural heritage. The limitations and recommendations for future research are also discussed. This review contributes to our understanding of the cultural, symbolic, and aesthetic significance of rock art and highlights the importance of interdisciplinary perspectives and engagement with local communities in the study and conservation of rock art sites and cultural heritage.

      • KCI등재

        Parametric inference based on judgment post stratified samples

        Omer Ozturk,K.S. Sultan,M.E. Moshref 한국통계학회 2018 Journal of the Korean Statistical Society Vol.47 No.1

        In this paper, we consider a judgment post stratified (JPS) sample of set size H from a location and scale family of distributions. In a JPS sample, ranks of measured units are random variables. By conditioning on these ranks, we derive the maximum likelihood (MLEs) and best linear unbiased estimators (BLUEs) of the location and scale parameters. Since ranks are random variables, by considering the conditional distributions of ranks given the measured observations we construct Rao-Blackwellized version of MLEs and BLUEs. We show that Rao-Blackwellized estimators always have smaller mean squared errors than MLEs and BLUEs in a JPS sample. In addition, the paper provides empirical evidence for the efficiency of the proposed estimators through a series of Monte Carlo simulations.

      • KCI등재

        Analysis of Changes in the Glomerular Filtration Rate as Measured by the Cockroft-Gault Formula in the Early Period after Percutaneous Nephrolithotomy

        Omer Bayrak,Ilker Seckiner,Sakip M. Erturhan,Sedat Mizrak,Ahmet Erbagci 대한비뇨의학회 2012 Investigative and Clinical Urology Vol.53 No.8

        Purpose: We aimed to analyze the changes in kidney function during the postoperative early period caused by the application of percutaneous nephrolithotomy (PNL), which is commonly used in kidney stone surgery. Materials and Methods: PNL was performed in 80 patients (48 men, 32 women) with kidney stones. The mean age of the patients was 43.71 years (range, 18 to 71 years). Preoperative and postoperative values for stone size, glomerular filtration rate (GFR), serum creatinine, urea, electrolytes (Na, K, Cl), and Hb were compared in 80 patients in whom PNL surgery was performed. The formula of Cockroft-Gault was used to calculate the GFR during the early postoperative period (72 to 96 hours). Results: Statistically significant decreases after PNL were observed in average stone size (preoperative, 627.75±375.10 mm2; postoperative, 81.70±16.15 mm2), serum urea (preoperative, 38.40±17.26 mg/dl; postoperative, 33.28±16.98 mg/dl), and creatinine (preoperative, 1.03±0.53 mg/dl; postoperative, 0.97±0.55 mg/dl) and an increase was observed in GFR (preoperative, 104.30±37.30 ml/min; postoperative, 112.38±40.1 ml/min). No changes were detected in the serum electrolyte values (Na, K, Cl). Multiple access, operation time, and type of lithotripter did not have any significant effects on the change in the GFR. Conclusions: In light of our results, PNL for kidney stone operations appears to be a reliable and efficient method that provides recovery of kidney functions in the early post-operative period by increasing the GFR and with high stone-free rates. Purpose: We aimed to analyze the changes in kidney function during the postoperative early period caused by the application of percutaneous nephrolithotomy (PNL), which is commonly used in kidney stone surgery. Materials and Methods: PNL was performed in 80 patients (48 men, 32 women) with kidney stones. The mean age of the patients was 43.71 years (range, 18 to 71 years). Preoperative and postoperative values for stone size, glomerular filtration rate (GFR), serum creatinine, urea, electrolytes (Na, K, Cl), and Hb were compared in 80 patients in whom PNL surgery was performed. The formula of Cockroft-Gault was used to calculate the GFR during the early postoperative period (72 to 96 hours). Results: Statistically significant decreases after PNL were observed in average stone size (preoperative, 627.75±375.10 mm2; postoperative, 81.70±16.15 mm2), serum urea (preoperative, 38.40±17.26 mg/dl; postoperative, 33.28±16.98 mg/dl), and creatinine (preoperative, 1.03±0.53 mg/dl; postoperative, 0.97±0.55 mg/dl) and an increase was observed in GFR (preoperative, 104.30±37.30 ml/min; postoperative, 112.38±40.1 ml/min). No changes were detected in the serum electrolyte values (Na, K, Cl). Multiple access, operation time, and type of lithotripter did not have any significant effects on the change in the GFR. Conclusions: In light of our results, PNL for kidney stone operations appears to be a reliable and efficient method that provides recovery of kidney functions in the early post-operative period by increasing the GFR and with high stone-free rates.

      • Frequency, bending and buckling loads of nanobeams with different cross sections

        Civalek, Omer,Uzun, Busra,Yayli, M. Ozgur Techno-Press 2020 Advances in nano research Vol.9 No.2

        The bending, stability (buckling) and vibration response of nano sized beams is presented in this study based on the Eringen's nonlocal elasticity theory in conjunction with the Euler-Bernoulli beam theory. For this purpose, the bending, buckling and vibration problem of Euler-Bernoulli nanobeams are developed and solved on the basis of nonlocal elasticity theory. The effects of various parameters such as nonlocal parameter e<sub>0</sub>a, length of beam L, mode number n, distributed load q and cross-section on the bending, buckling and vibration behaviors of carbon nanotubes idealized as Euler-Bernoulli nanobeam is investigated. The transverse deflections, maximum transverse deflections, vibrational frequency and buckling load values of carbon nanotubes are given in tables and graphs.

      • SCIESCOPUSKCI등재

        Body Weight Change, Milk Production and Reproductive Parameters in Suckled vs. Non-suckled Awassi Ewes

        Ishmais, M.A. Abu,Kridli, R.T.,Omer, S.A. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.9

        The objective of this study was to identify the effect of early weaning on body weight change, milk production and the return to estrus in Awassi ewes. Twenty multiparous winter-lambing Awassi ewes were randomly assigned to either suckled (S, n=10) or non-suckled (NS, n=10) groups in a completely randomized design. Lambs in the NS group were removed from their dams on day 2 postpartum (PP). Animal body weights (BW) and body condition scores (BCS) were recorded at the beginning of the study and every 3 weeks thereafter until the end of the experiment. Milk production was estimated by machine milking at weekly intervals for 4 weeks beginning on d 11 PP. Blood samples were collected from each ewe every third day for 4 weeks beginning on day 15 PP. Initial body weight was similar for both treatments. By the end of the experiment, NS ewes gained an average of 1.8${\pm}$1.0 kg while S ewes lost an average of 7.0${\pm}$1.0 kg (p<0.001). Body condition scores followed a trend similar to that observed for BW and was greater (p<0.001) in the NS ewes. Significant correlation existed (p<0.01) between BW and BCS (r=0.77). The first milk production recording for both suckled and non-suckled was similar. Later recordings, however, showed that the S group had greater milk production (p<0.01) compared with the NS group. Lambs in the NS group were heavier (p<0.05) than those in the S group on d 10 PP. By the end of the study, lamb weights in the NS group were significantly lower (p<0.001) when compared with S group. The first rise in plasma progesterone ($P_{4}$) occurred earlier (p<0.05) in the NS than S ewes (day 27.0${\pm}$2.2 vs. 34.0${\pm}$2.2 postpartum, respectively). All of the NS ewes (10/10) and 60% (6/10) of the S ewes expressed estrus following ram introduction (p<0.05). Results of the current study indicate that non-suckled ewes gained more weight and displayed ovarian activity earlier than suckled ewes. Early lamb removal can be used to obtain biannual lambing in Awassi sheep.

      • A Fourier sine series solution of static and dynamic response of nano/micro-scaled FG rod under torsional effect

        Civalek, Omer,Uzun, Busra,Yayli, M. Ozgur Techno-Press 2022 Advances in nano research Vol.12 No.5

        In the current work, static and free torsional vibration of functionally graded (FG) nanorods are investigated using Fourier sine series. The boundary conditions are described by the two elastic torsional springs at the ends. The distribution of functionally graded material is considered using a power-law rule. The systems of equations of the mechanical response of nanorods subjected to deformable boundary conditions are achieved by using the modified couple stress theory (MCST) and taking the effects of torsional springs into account. The idea of the study is to construct an eigen value problem involving the torsional spring parameters with small scale parameter and functionally graded index. This article investigates the size dependent free torsional vibration based on the MCST of functionally graded nano/micro rods with deformable boundary conditions using a Fourier sine series solution for the first time. The eigen value problem is constructed using the Stokes' transform to deformable boundary conditions and also the convergence and accuracy of the present methodology are discussed in various numerical examples. The small size coefficient influence on the free torsional vibration characteristics is studied from the point of different parameters for both deformable and rigid boundary conditions. It shows that the torsional vibrational response of functionally graded nanorods are effected by geometry, small size effects, boundary conditions and material composition. Furthermore, for all deformable boundary conditions in the event of nano-sized FG nanorods, the incrementing of the small size parameters leads to increas the torsional frequencies.

      • Size dependent torsional vibration of a rotationally restrained circular FG nanorod via strain gradient nonlocal elasticity

        Busra Uzun,Omer Civalek,M. Ozgur Yayli Techno-Press 2024 Advances in nano research Vol.16 No.2

        Dynamical behaviors of one-dimensional (1D) nano-sized structures are of great importance in nanotechnology applications. Therefore, the torsional dynamic response of functionally graded nanorods which could be used to model the nano electromechanical systems or micro electromechanical systems with torsional motion about the center of twist is examined based on the theory of strain gradient nonlocal elasticity in this work. The mathematical background is constructed based on both strain gradient theory and Eringen's nonlocal elasticity theory. The equation of motions and boundary conditions of radially functionally graded nanorods are derived using Hamilton's principle and then transformed into the eigenvalue analysis by using Fourier sine series. A general coefficient matrix is obtained to assemble the Stokes' transformation. The case of a restrained functionally graded nanorod embedded in two elastic springs against torsional rotation is then deeply investigated. The effect of changing the functionally graded index, the stiffness of elastic boundary conditions, the length scale parameter and nonlocal parameter are investigated in detail.

      • Confinement effectiveness of CFRP strengthened concrete cylinders subjected to high temperatures

        Raoof, Saad M.,Ibraheem, Omer F.,Tais, Abdulla S. Techno-Press 2020 Advances in concrete construction Vol.9 No.6

        The current study investigated experimentally the effectiveness of Carbon Fiber Reinforced Polymer (CFRP) in confining concrete cylinders after being subjected to high temperature. Parameters examined were: (a) the exposing temperatures (20, 100, 200, 400 600 and 700℃) and (b) the number of CFRP layers (1 and 3 layers). A uniaxial compressive testing was carried out on 36 concrete cylinders with dimensions of 150 mm×300 mm. The results obtained show that the compressive strength reduced with the increased of temperature compared to that measured at 20℃. In particular, the reduction in the compressive strength was more observed when the temperature exceeded 400℃. Further, the concrete cylinders confined with one and three layers of CFRP significantly increased the compressive strength compared to the counterpart unconfined specimen tested at the same temperature. Also, the average percentages of the increase in the compressive strength were approximately 112% and 158% when applying 1 and 3 layers of CFRP, respectively, compared to the counterpart unstrengthened specimen tested at the same temperature.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼