• 제목/요약/키워드: Matter

검색결과 12,542건 처리시간 0.047초

Cosmological Parameter Estimation from the Topology of Large Scale Structure

  • Appleby, Stephen
    • 천문학회보
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    • 제44권2호
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    • pp.53.2-53.2
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    • 2019
  • The genus of the matter density eld, as traced by galaxies, contains information regarding the nature of dark energy and the fraction of dark matter in the Universe. In particular, this topological measure is a statistic that provides a clean measurement of the shape of the linear matter power spectrum. As the genus is a topological quantity, it is insensitive to galaxy bias and gravitational collapse. Furthermore, as it traces the linear matter power spectrum, it is a conserved quantity with redshift. Hence the genus amplitude is a standard population that can be used to test the distance-redshift relation. In this talk, I present measurements of the genus extracted from the SDSS DR7 LRGs in the local Universe, and also slices of the BOSS DR12 data at higher redshift. I show how these combined measurements can be used to place cosmological parameter constraints on m, wde.

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호기성 그래뉼 슬러지를 이용한 축산폐수의 생물학적 처리에 관한 연구 (Biological Treatment of Livestock Wastewater using Aerobic Granular Sludge )

  • 김현구;안대희
    • 한국환경과학회지
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    • 제32권7호
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    • pp.483-492
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    • 2023
  • In this study, the treatment of livestock wastewater using an aerobic granular sludge based sequencing batch reactor was investigated. The reactor operation was carried out by general injection and split injection methods. The average removal efficiency of organic matter after the adaptation period was 71.5 and 87.4%, respectively. Some untreated organic matter was attributed to recalcitrant organic matter. The average removal efficiency of total nitrogen was 65.6 and 88.4%, respectively. These results indicate that the denitrification reaction by split injection was carried out smoothly. As for the solids, the ratio of aerobic granular sludge/mixed liquor suspended solid can be determined as the main factor of the process operation, and the ratio increased gradually and finally reached 86.0%. Correspondingly, the sludge volume index (SVI) was also improved, reaching 54 mL/g at the end of operation, and it is believed that the application of a short settling time contributed to the improvement of settleability.

Long arm octopus (Octopus minor) extract prevents eye injury caused by particulate matter exposure in zebrafish (Danio rerio) embryos

  • Thilini Ranasinghe;Seon-Heui Cha
    • Fisheries and Aquatic Sciences
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    • 제27권2호
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    • pp.111-121
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    • 2024
  • Particulate matter (PM) is a mixture of microscopic solid inhalable particles including airborne liquid droplets, and it is implicated with several diseases. The eye does not have a protective barrier among the human organs, consequently it get directly exposed to environmental substances such as PM. The scarcity of treatments for damage to the eyesight and the vision and eye structure being closely related to the structure and function of the central nervous system highlights the cruciality of novel therapeutics. In this study was conducted using in vivo zebrafish vertebrate model which is a useful model due to the conserved genes between human. We found that protective effect of Octopus minor extract against particulate matter-induced adverse effects on eye development in zebrafish (Danio rerio) embryos by regulating antioxidant and anti-inflammatory mRNA expression.

Voluntary Intake and Digestibility of Saltbush by Sheep

  • Abu-Zanat, M.M.W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권2호
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    • pp.214-220
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    • 2005
  • The study was conducted to compare the dry matter intake and digestibility of Atriplex halimus (AH) and Atriplex nummularia (AN) and determine the proper proportion of saltbushes for partial replacement of alfalfa hay in the diets of Awassi sheep. The foliage of AH and AN were hand-plucked, air-dried in shade and then chopped mechanically similar to alfalfa hay. Two trials were conducted separately to determine voluntary feed intake and digestibility of saltbush browse. In the first trial, fifteen 8 month old Awassi lambs were distributed into 3 equal groups, and each animal was housed in individual pen. Each group received one of three dietary treatments: chopped alfalfa hay (H), dried foliage of Atriplex nummularia or foliage of Atriplex halimus. In the second trial, twentyseven 12 months old Awassi male lambs were randomly selected, distributed into nine equal groups, and housed into metabolic crates. Each group of animals received one of nine dietary treatments: alfalfa hay, AN, AH and different proportions (25, 50 and 75%) of AN or AH mixed with alfalfa hay. Forage type had a significant (p<0.001) effect on dry matter intake (DMI) and growth rate of lambs of the voluntary feed intake trial. Lambs receiving the alfalfa hay diet showed high DMI and high growth rate compared to those fed the diets containing saltbush. In the digestibility trial, dietary treatments had significant (p<0.05) effect on DMI, dry matter digestibility (DMD) (p<0.01) and organic matter digestibility (OMD) (p<0.01). The inclusion of AN in the diet up to 50% had no significant effect on DMI and DMD, whereas the inclusion of AH above 25% reduced DMI, DMD and OMD. The treatments had significant (p<0.05) effect on water intake and on live weight changes of lambs. Except for the diet containing 25% of AN browse, all lambs fed diets containing the saltbushes exhibited loss in body weight. The nutritive value of Atriplex nummularia foliage is better than that of A. halimus and it is possible to replace up to 50% of alfalfa hay by A. nummularia without negative effects on intake and digestibility of dry matter.