Evolution of galaxy groups in the Illustris simulation

We present the first study of evolution of galaxy groups in the Illustris simulation. We focus on dynamically relaxed and unrelaxed galaxy groups representing dynamically evolved and evolving galaxy systems, respectively. The evolutionary state of a group is probed from its luminosity gap and separation between the brightest group galaxy and the center of mass of the group members. We find that the Illustris simulation, over-produces large luminosity gap galaxy systems, known as fossil systems, in comparison to observations and the probed semi-analytical predictions. However, this simulation is equally successful in recovering the correlation between luminosity gap and luminosity centroid offset, in comparison to the probed semi-analytic model. We find evolutionary tracks based on luminosity gap which indicate that a large luminosity gap group is rooted in a small luminosity gap group, regardless of the position of the brightest group galaxy within the halo. This simulation helps, for the first time, to explore the black hole mass and its accretion rate in galaxy groups. For a given stellar mass of the brightest group galaxies, the black hole mass is larger in dynamically relaxed groups with a lower rate of mass accretion. We find this consistent with the latest observational studies of the radio activities in the brightest group galaxies in fossil groups. We also find that the IGM in dynamically evolved groups is hotter for a given halo mass than that in evolving groups, again consistent with earlier observational studies.Comment: 10 pages, 10 figures. Accepted for publication in Ap

Epizootiološko istraživanje slinavke i šapa u Sudanu: stanje nakon dva desetljeća

In order to update information on the situation regarding foot and mouth disease (FMD) in the Sudan, a serosurvey and disease survey were conducted. Recently collected data on FMD in the Sudan showed that FMD is a major constraint to animal production in the country. It presents no threat nor does it cause mild disease in sheep and goats. The disease, with obvious clinical signs, has been detected in cattle only, and is caused by serotype O and SAT 2. Seasonal occurrence of the disease in the cold, dry season has been observed and animal movement seems to play a major role in virus dissemination. A total of 1,069 sera were collected from cattle, sheep, goats, and camel, from seven states in the Sudan, for the detection of antibodies to FMDV. Application of liquid phase blocking (LPB) ELISA revealed that antibodies to four serotypes were present in ruminants; namely O, A, SAT 1 and SAT 2. No antibodies to FMDV were detected in camel sera. The results differed from early reports regarding the prevalence of serotype specifi c antibodies in different species; for instance, in cattle, the antibodies to type A (78.13%) surpassed that of type O (69.39%) and the antibodies to type SAT 2 (44%) surpassed that of type SAT 1 (20.2%). This work elucidates the current epidemiology of FMD in some parts of the Sudan.Radi pružanja informacija o sadašnjem stanju slinavke i šapa u Sudanu provedena su serološka istraživanja te je prikazana njezina pojavnost. Svježe prikupljeni podatci o pojavi slinavke i šapa u Sudanu pokazali su da ona predstavlja veliku prepreku životinjskoj proizvodnji u toj zemlji. U ovaca i koza javlja se kao blaga bolest i ne predstavlja veliku prijetnju, dok se u goveda javlja s očitim kliničkim znakovima, a uzrokovana je serotipovima O i SAT 2. Bolest se javlja sezonski u hladnoj i suhoj sezoni, a promet životinjama ima glavnu ulogu u širenju virusa. Ukupno je bilo prikupljeno 1069 uzoraka seruma goveda, ovaca, koza i deva podrijetlom iz sedam država u Sudanu radi pretrage na prisutnost protutijela za virus slinavke i šapa. Blokirajućim imunonenzimnim testom dokazana su protutijela za četiri serotipa virusa: O, A, SAT 1 i SAT 2. Protutijela za virus slinavke i šapa nisu bila dokazana u uzorcima seruma deva. Rezultati se razlikuju od ranijih izvješća s obzirom na prevalenciju specifi čnih protutijela u različitih vrsta. Npr., specifi čna protutijela za serotip A dokazana su u 78,13% goveda, za serotip O u 69,39%, serotip SAT 2 u 44% te serotip SAT 1 u 20,2% goveda. U radu je prikazano sadašnje epizootiološko stanje slinavke i šapa u nekim dijelovima Sudana

Isolation and Molecular Identification of Insecticidal Activity Bacillus Thuringiensis Strain Alex-13 Isolated From Different Ecosystems in Egypt against Spodoptera Littolaris

The entomopathogenic bacterium Bacillus thuringiensis (Bt) is the most widely used biopesticide. The specific toxic activity to insects and other organisms is related to the presence of crystals that have different morphologies, sizes, numbers and compositions according to the Bt strain. The crystals contain different proteins, which are encoded by distinctCry (crystal) genes. In this work we isolated 334 colonies from 59 soil samples in 13 local area in Egypt, colonies examination has carried out under microscope for toxin production, during screening of these isolates we found 16 bacterial strains has been identified by using biochemical reactions and insecticidal activity against Spodoptera littolaris inaddition to Bacillus thuringiensis wettable powder comparable to standard strain, only one isolate which are considered most potent strain were confirmed by molecular characterization. Scanning electron microscopy observed that the presence of cuboidal crystals in Bacillus thuringiensis Alex-13, and observed bipyramidal crystals in case of Bacillus thuringiensisHD-1, as standard strain. Polymerase chain reactions (PCR) revealed the presence of Cry1-like sequences in addition to standard strain, which confirmed by gel electrophoresis. Also, during the studying environmental and nutritional conditions requirements (data not show). Bioassay recorded that the highest mortality rate by determination of LC50 for 5 days againstSpodoptera littolaris third instars larvae were 69, 86, and 100(%) in case of Bt Alex-13, Bt-HD-1 standard strain and Bt commercial wettable powder, respectively

The impact of the dynamical state of galaxy groups on the stellar populations of central galaxies

We study the stellar populations of the brightest group galaxies (BGGs) in groups with different dynamical states, using Galaxy And Mass Assembly survey data. We use two independent, luminosity-dependent indicators to probe the relaxedness of their groups: the magnitude gap between the two most luminous galaxies (ΔM 12), and the offset between BGGs and the luminosity center (D offset) of the group. Combined, these two indicators were previously found useful for identifying relaxed and unrelaxed groups. We find that the BGGs of unrelaxed groups have significantly bluer near-ultraviolet-r colors than in relaxed groups. This is also true at the fixed sersic index. We find the bluer colors cannot be explained away by differing dust fraction, suggesting there are real differences in their stellar populations. Star formation rates derived from spectral energy distribution (SED) fitting tend to be higher in unrelaxed systems. This is in part because of a greater fraction of BGGs with non-elliptical morphology, but also because unrelaxed systems have larger numbers of mergers, some of which may bring fuel for star formation. The SED-fitted stellar metallicities of BGGs in unrelaxed systems also tend to be higher by around 0.05 dex, perhaps because their building blocks were more massive. We find that the ΔM 12 parameter is the most important parameter behind the observed differences in the relaxed/unrelaxed groups, in contrast with the previous study of Trevisan et al. We also find that groups selected to be unrelaxed using our criteria tend to have higher velocity offsets between the BGG and their group.Publisher PDFPeer reviewe

Characterization and Toxicity of Bacillus Thuringiensis Strain Kfr-24, And Commercial Formulations against Spodoptera Littolaris

Under these studies Bacillus thuringiensis wettable powder comparable to standard strain, there are only one isolate which confirmed by molecular characterization. Scanning electron microscopy observed that the presence of cuboidal crystals in Bacillus thuringiensis Alex-13 and observed bipyramidal crystals in case of Bacillus thuringiensis HD-1, as standard strain. Polymerase chain reactions (PCR) revealed the presence of Cry1-like sequences in addition to standard strain, which confirmed by gel electrophoresis. Also, during these studies. Bioassay recorded that the highest mortality rate by determination of LC50 for 5 days against Spodoptera littolaris third instars larvae were 69, 86, and 100(%) in case of Bt Alex-13, Bt-HD-1 standard strain and Bt commercial wettable powder, respectively

Isolation and Molecular Identification of Insecticidal Activity Bacillus Thuringiensis Strain Alex-13 Isolated from Different Ecosystems in Egypt against Spodoptera Littolaris

The entomopathogenic bacterium Bacillus thuringiensis (Bt) is the most widely used biopesticide. The specific toxic activity to insects and other organisms is related to the presence of crystals that have different morphologies, sizes, numbers and compositions according to the Bt strain. The crystals contain different proteins, which are encoded by distinct Cry (crystal) genes. In this work we isolated 334 colonies from 59 soil samples in 13 local area in Egypt, colonies examination has carried out under microscope for toxin production, during screening of these isolates we found 16 bacterial strains has been identified by using biochemical reactions and insecticidal activity against Spodoptera littolaris in addition to Bacillus thuringiensis wettable powder comparable to standard strain, only one isolate which are considered most potent strain were confirmed by molecular characterization. Scanning electron microscopy observed that the presence of cuboidal crystals in Bacillus thuringiensis Alex-13 and observed bipyramidal crystals in case of Bacillus thuringiensis HD-1, as standard strain. Polymerase chain reactions (PCR) revealed the presence of Cry1-like sequences in addition to standard strain, which confirmed by gel electrophoresis. Also, during the studying environmental and nutritional conditions requirements (data not show). Bioassay recorded that the highest mortality rate by determination of LC50 for 5 days against Spodoptera littolaris third instars larvae were 69, 86, and 100(%) in case of Bt Alex-13, Bt-HD-1 standard strain and Bt commercial wettable powder, respectively

Characterization and Toxicity of Bacillus Thuringiensis Strain Kfr-24, And Commercial Formulations against Spodoptera Littolaris

Under these studies Bacillus thuringiensis wettable powder comparable to standard strain, there are only one isolate which confirmed by molecular characterization. Scanning electron microscopy observed that the presence of cuboidal crystals in Bacillus thuringiensis Alex-13, and observed bipyramidal crystals in case of Bacillus thuringiensis HD-1, as standard strain. Polymerase chain reactions (PCR) revealed the presence of Cry1-like sequences in addition to standard strain, which confirmed by gel electrophoresis. Also, during these studies.Bioassay recorded that the highest mortality rate by determination of LC50 for 5 days against Spodoptera littolaris third instars larvae were 69, 86, and 100(%) in case of Bt Alex-13, Bt-HD-1 standard strain and Bt commercial wettable powder, respectively

Analyzing the Influence of Design and Operating Conditions on Combustion and Emissions in Premixed Turbulent Flames: A Comprehensive Review

Recently, premixed combustion has dominated the field of combustion research worldwide. The current work is a review that addresses the effects of design and operating regimes on the combustion and emission characteristics of premixed turbulent flames. The study accounts for recent developments aimed at overcoming combustor operability issues that influence emissions and flame stability. Various experimental setups have been utilized in investigations, with results pertaining to performance and emissions concerning premixed turbulent flames. Thus, the objective of this paper is to provide a comprehensive review of the effects of swirl vane angles and equivalence fuel-air ratios for tests conducted both with and without secondary air, aiming to improve combustion performance and reduce emissions. This review extensively analyzes published studies to provide and discuss different strategies for controlling premixed turbulent combustion techniques within a wide range of swirl vane angles and equivalence air-fuel ratios

Experimental Study on the Impact of Secondary Air Injection and different swirl van angles on Premixed Turbulent Flame Propagation and Emission Behaviors

The objective of the present paper is to investigate experimentally the flame characteristics utilizing different secondary air inlet direction for different primary air swirl numbers and equivalence fuel-air ratios. In this study, an experimental test rig was carried out to investigate the flame temperature and emission behavior with flame length at the equivalence fuel-air ratios taken0.96, 0.80, 0.70, and 0.60, and swirl vane angles were varied as 20, 30, 45, and 60° to generate different swirl numbers of 0.26, 0.416, 0.71 and 1.23, respectively. In addition to the introduction of secondary air in test combustor, whereas the primary air and fuel mass flow rates were kept constant at 12.5. Also, the secondary air flow rate was changed to give different secondary over primary air and fuel ratios of 0.19, 0.32, 0.41, and 0.48. The study showed that the flame temperature distribution with flame length at the equivalence fuel-air ratios is increased at 20.0 mm of radial flame distance and decreases gradually with radial flame distance. Also, the experimental investigation illustrated the emission characteristics at different equivalence fuel-air ratios accounting for nitrogen oxide and unburned hydrocarbon were decreased gradually with radial flame distance at different swirl vane angles. Moreover, the emission characteristics at different equivalence fuel-air ratios accounting for the concentration percent of carbon dioxide and carbon monoxide were decreased gradually with radial flame distance at different swirl vane angle