578 research outputs found
Galaxy And Mass Assembly (GAMA): end of survey report and data release 2
The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ˜286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm-1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sérsic fits, stellar masses, Hα-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72 225 objects in total). The data base serving these data is available at http://www.gama-survey.org/
Evaluation of Bioactive Compounds in Nutrition Physiology
Many peptides released from animal or plant proteins in vitro or in vivo have therapeutic functions in humans beyond bioactivity and adequate nutrition. Different health effects have been attributed to foodborne peptides, including antimicrobial properties, blood pressure lowering (ACE inhibitor) effects, cholesterol lowering ability, antithrombotic and antioxidant activities, increased mineral absorption, immunomodulatory effects and opioid activities. For this reason, nutritional counseling practices deal with these issues. Specific protein fractions with therapeutic effects on body function and health are termed biological peptides and have been shown to have a direct positive effect on health. Angiotensin I-converting enzyme (ACE) is a carboxy-dipeptidyl metallopeptidase associated with the renin angiotensin system that regulates the production of angiotensin II from vasoconstrictor angiotensin-II and peripheral blood pressure that catalyzes the inactivation of vasodilator bradykinin. For this reason, the ACE inhibitor substance in the diet may inhibit hypertension by inhibiting the renin-angiotensin system. Milk proteins are now the main source of bioactive peptides. Such peptides are seen as natural and non-effective alternatives to drugs in the treatment of hypertension. The natural consumption of biological peptides will not be expected to cause side effects of synthetically produced drugs used to control hypertension. Therefore, it can be used as a powerful functional food additive and the ACE inhibitor is a natural and healthy alternative to drugs
Evaluation of Bioactive Compounds in Nutrition Physiology
Many peptides released from animal or plant proteins in vitro or in vivo have therapeutic functions in humans beyond bioactivity and adequate nutrition. Different health effects have been attributed to foodborne peptides, including antimicrobial properties, blood pressure lowering (ACE inhibitor) effects, cholesterol lowering ability, antithrombotic and antioxidant activities, increased mineral absorption, immunomodulatory effects and opioid activities. For this reason, nutritional counseling practices deal with these issues. Specific protein fractions with therapeutic effects on body function and health are termed biological peptides and have been shown to have a direct positive effect on health. Angiotensin I-converting enzyme (ACE) is a carboxy-dipeptidyl metallopeptidase associated with the renin angiotensin system that regulates the production of angiotensin II from vasoconstrictor angiotensin-II and peripheral blood pressure that catalyzes the inactivation of vasodilator bradykinin. For this reason, the ACE inhibitor substance in the diet may inhibit hypertension by inhibiting the renin-angiotensin system. Milk proteins are now the main source of bioactive peptides. Such peptides are seen as natural and non-effective alternatives to drugs in the treatment of hypertension. The natural consumption of biological peptides will not be expected to cause side effects of synthetically produced drugs used to control hypertension. Therefore, it can be used as a powerful functional food additive and the ACE inhibitor is a natural and healthy alternative to drugs
SUPPORT MATERIAL ALTERNATIVES FOR BIOLOGICAL FILTER REACTORS (BFRs)
Biyolojik Filtre Reaktörler (BFR) klasik filtre sistemlerinin modifiye edilerek atıksu arıtımı amacıyla kullanıldığı yeni teknolojilerdir. Günümüzde farklı isimler altında geliştirilen biyolojik filtreleri birbirinden ayıran özelliklerin başında filtrelerde kullanılan dolgu malzemeleri gelmektedir. Sunulan makalede “pellet†olarak isimlendirilen, su yumuşatma sistemlerinden atık olarak çıkan bir malzemenin BFR'de dolgu malzemesi olarak kullanılabilirliği incelenmiştir. Bu kapsamda, Türk Standartları Enstitüsü'nün (TSE) ilgili şartnamelerinde açıklanan analiz yöntemleri kullanılarak malzemenin tane boyutu dağılımı, özgül ağırlık, birim hacim ağırlık, porozite, özgül yüzey alanı gibi fiziksel özellikleri belirlenmiştir. Laboratuvarda kurulu bir filtre kolonundan yararlanılarak malzemenin akışkanlaşma özellikleri (minimum akışkanlaşma hızı) araştırılmıştır. Ayrıca, yukarı akışlı akışkan yatak olarak işletilen bir reaktöre “pellet†doldurularak malzemenin atıksu arıtımı amacıyla kullanılabilirliği incelenmiş; organik madde giderimi esas alınarak arıtma verimi değerlendirilmiştir. Biological Filter Reactors (BFRs) are modified conventional filter systems which were used for wastewater treatment in recent years. One of the most substantial differences among the BFRs, which are currently developed with various trade names, is the nature of support material. In this study, a new support material called as “pellet†which is the waste material of water softening process was investigated as filter media in the BFRs. The major physical characteristics of pellet such as particle size distribution, specific weight, porosity, specific surface area were determined by using standard test methods set by Turkish Institute of Standards (TSE). Fluidisation characteristics such as minimum fluidisation velocity of pellets were also studied in a deep bed filter column. In addition pellet material was used in an up-flow fluidised bed filter reactor and the performance of the reactor in terms of COD removal was evaluated
Galaxy And Mass Assembly (GAMA): growing up in a bad neighbourhood - how do low-mass galaxies become passive?
Both theoretical predictions and observations of the very nearby Universe
suggest that low-mass galaxies (log[M/M]<9.5) are likely
to remain star-forming unless they are affected by their local environment. To
test this premise, we compare and contrast the local environment of both
passive and star-forming galaxies as a function of stellar mass, using the
Galaxy and Mass Assembly survey. We find that passive fractions are higher in
both interacting pair and group galaxies than the field at all stellar masses,
and that this effect is most apparent in the lowest mass galaxies. We also find
that essentially all passive log[M/M]<8.5 galaxies are
found in pair/group environments, suggesting that local interactions with a
more massive neighbour cause them to cease forming new stars. We find that the
effects of immediate environment (local galaxy-galaxy interactions) in forming
passive systems increases with decreasing stellar mass, and highlight that this
is potentially due to increasing interaction timescales giving sufficient time
for the galaxy to become passive via starvation. We then present a simplistic
model to test this premise, and show that given our speculative assumptions, it
is consistent with our observed results.Comment: 20 pages, 12 figures, Accepted to MNRA
Galaxy And Mass Assembly (GAMA): trends in galaxy colours, morphology, and stellar populations with large-scale structure, group, and pair environments
We explore trends in galaxy properties with Mpc-scale structures using catalogues of environment and large scale structure from the Galaxy And Mass Assembly (GAMA) survey. Existing GAMA catalogues of large scale structure, group and pair membership allow us to construct galaxy stellar mass functions for different environmental types. To avoid simply extracting the known underlying correlations between galaxy properties and stellar mass, we create a mass matched sample of galaxies with stellar masses between 9.5≤logM∗/h−2M⊙≤11 for each environmental population. Using these samples, we show that mass normalised galaxies in different large scale environments have similar energy outputs, u−r colours, luminosities, and morphologies. Extending our analysis to group and pair environments, we show galaxies that are not in groups or pairs exhibit similar characteristics to each other regardless of broader environment. For our mass controlled sample, we fail to see a strong dependence of S\'{e}rsic index or galaxy luminosity on halo mass, but do find that it correlates very strongly with colour. Repeating our analysis for galaxies that have not been mass controlled introduces and amplifies trends in the properties of galaxies in pairs, groups, and large scale structure, indicating that stellar mass is the most important predictor of the galaxy properties we examine, as opposed to environmental classifications
Galaxy And Mass Assembly (GAMA) : The mechanisms for quiescent galaxy formation at z<1
© 2016 The Authors. One key problem in astrophysics is understanding how and why galaxies switch off their star formation, building the quiescent population that we observe in the local Universe. From the Galaxy And Mass Assembly and VIsible MultiObject Spectrograph Public Extragalactic Redshift surveys, we use spectroscopic indices to select quiescent and candidate transition galaxies.We identify potentially rapidly transitioning post-starburst (PSB) galaxies and slower transitioning green-valley galaxies. Over the last 8Gyr, the quiescent population has grown more slowly in number density at high masses (M * > 10 11 M ⊙ ) than at intermediate masses (M * > 10 10.6 M ⊙ ). There is evolution in both the PSB and green-valley stellar mass functions, consistent with higher mass galaxies quenching at earlier cosmic times.At intermediatemasses (M * > 10 10.6 M ⊙ ), we find a green-valley transition time-scale of 2.6 Gyr. Alternatively, at z ~ 0.7, the entire growth rate could be explained by fast-quenching PSB galaxies, with a visibility time-scale of 0.5 Gyr. At lower redshift, the number density of PSBs is so low that an unphysically short visibility window would be required for them to contribute significantly to the quiescent population growth. The importance of the fast-quenching route may rapidly diminish at z 10 11 M ⊙ ), there is tension between the large number of candidate transition galaxies compared to the slow growth of the quiescent population. This could be resolved if not all high-mass PSB and green-valley galaxies are transitioning from star forming to quiescent, for example if they rejuvenate out of the quiescent population following the accretion of gas and triggering of star formation, or if they fail to completely quench their star formation
Creating smarter teaching and training environments: innovative set-up for collaborative hybrid learning
This paper brings together previous work from a number of research projects and teaching initiatives in an effort to introduce good practice in setting up supportive environments for collaborative learning. The paper discusses prior use of social media in learning support, the role of dashboards for learning analytics in Global Software Development training, the use of optical head-mounted displays for feedback and the use of NodeXl visualization in managing distributed teams. The scope of the paper is to provide a structured approach in organizing the creation of smarter teaching and training environments and explore ways to coordinate learning scenarios with the use of various techniques. The paper also discusses challenges from integrating multiple innovative features in educational contexts. Finally the paper attempts to investigate the use of smart laboratories in establishing additional learning support and gather primary data from blended and hybrid learning pilot studies
Ambiguity, multiple streams, and EU policy
The multiple streams framework draws insight from interactions between agency and institutions to explore the impact of context, time, and meaning on policy change and to assess the institutional and issue complexities permeating the European Union (EU) policy process. The authors specify the assumptions and structure of the framework and review studies that have adapted it to reflect more fully EU decision-making processes. The nature of policy entrepreneurship and policy windows are assessed to identify areas of improvement. Finally, the authors sketch out a research agenda that refines the logic of political manipulation which permeates the lens and the institutional complexity which frames the EU policy process
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