Abstract
Application of the HIJING, EPOS 1.99, UrQMD and Geant4 FTF models for the analysis of experimental data by the collaboration is considered. A short description of the models is given. It is ...shown that the FTF (FRITIOF) model of the Geant4 toolkit describes well the NA61/SHINE data on
$$\pi ^-$$
π
-
meson rapidity distributions in
$${ ^{40}\mathrm{Ar}+{}^{45}\mathrm{Sc}}$$
40
Ar
+
45
Sc
interactions at
$$\sqrt{s_{NN}}=$$
s
NN
=
5.2 and 6.1 GeV. At higher energies,
$$\sqrt{s_{NN}}=$$
s
NN
=
7.6, 8.8, 11.9 and 16.8 GeV, the model underestimates the data by 13%, 14%, 14% and 27%, respectively. The model also describes well the analogous data for
$${^{7}\mathrm{Be}+{}^{9}\mathrm{Be}}$$
7
Be
+
9
Be
interactions at all energies (
$$\sqrt{s_{NN}}=$$
s
NN
=
6.1–16.8 GeV). It is the best model description among the descriptions of other models considered by the collaboration.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Application of the HIJING, EPOS 1.99, UrQMD and Geant4 FTF models for the analysis of experimental data by the collaboration is considered. A short description of the models is given. It is shown ...that the FTF (FRITIOF) model of the Geant4 toolkit describes well the NA61/SHINE data on
π
-
meson rapidity distributions in
40
Ar
+
45
Sc
interactions at
s
NN
=
5.2 and 6.1 GeV. At higher energies,
s
NN
=
7.6, 8.8, 11.9 and 16.8 GeV, the model underestimates the data by 13%, 14%, 14% and 27%, respectively. The model also describes well the analogous data for
7
Be
+
9
Be
interactions at all energies (
s
NN
=
6.1–16.8 GeV). It is the best model description among the descriptions of other models considered by the collaboration.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Staphylococcus aureus is a significant pathogen frequently causing persistent intramammary infections (IMI) in dairy cows. We compared some genotypic and phenotypic characteristics of 285 strains ...collected from quarter milk samples from cows with persistent and nonpersistent subclinical IMI across Canada. Variable number of tandem repeats typing was used to infer the persistence of the same S. aureus strain in 3 consecutive quarter milk samples collected at intervals of 3 wk during lactation or before and after dry-off. All first isolates of the series were used as the representative strains from persistent IMI and were compared with nonpersistent strains for the presence of genes seg, sen, sec, and tst as well as by spa typing. Biofilm production in vitro and hld-RNAIII expression levels were also quantified. The gene seg was associated with a reduction in the likelihood of the bacteria to cause a persistent IMI during lactation. Strains persisting through the dry period produced significantly more biofilm in vitro than strains that do not persist after calving. Also, we showed that strains expressing more hld were more likely to be nonpersistent during either lactation or through the dry period. Three spa types were predominant (t529, t267, and a novel type: t13401). In the strains studied, the spa type tbl 2645 was the most frequent, and 97.0% of the strains of this spa type carried both sen and seg. Strains from the spa type tbl 2645 were less likely to cause a persistent IMI in the dry period. Most (86.7%) of the strains of the novel spa type (t13401) were negative for seg, sen, or both and produced significantly more biofilm in vitro than tbl 2645 and t267. The present study expanded our current knowledge on the genotypic and phenotypic traits of S. aureus strains recovered from persistent and nonpersistent IMI in Canada.
Bovine mastitis is the primary disease of dairy cattle that has a great impact on the dairy industry. It is estimated that worldwide economic losses due to mastitis range between US$82 and US$131 per ...cow/year. A fast and efficient diagnosis of the disease remains a major bottleneck that directly influences the speed with which treatment decisions and management are undertaken. Microbiological culture remains the gold standard in the identification of bacteria that cause mastitis, but the method has inherent limitations, such as a delay in obtaining results and cost, and requires special care during the collection and processing of the sample. For this reason, multiple groups have devoted efforts to develop alternative methods that, preferably, can be easily accomplished in the field. The specificity of the antigen–antibody reaction has enabled the emergence of major diagnostic methods used in clinical practice, such as immunoassays, which have significant advantages in terms of speed, sensitivity, specificity, and portability. Commercially, immunodiagnostics have been used in the detection of various diseases in cattle. However, in several cases, only a presumptive diagnosis can be made, which requires confirmation using culture-based methods. This review discusses the immunological-based assays developed since the 1990s for the detection of
Staphylococcus aureus
, which is considered the primary pathogen of contagious bovine mastitis. Although no ideal antigens ensure the accurate performance of tests and the costs need to be reduced to allow for good market competitiveness, immunoassays, particularly lateral flow immunoassay and immunoagglutination, have emerged as promising tests to be used in the field.
Abstract Sixteen healthy exercise trained participants underwent the following three, 10-h exposures in a randomized manner: (1) Hypobaric hypoxia (HH; 3450 m terrestrial altitude) (2) Normobaric ...hypoxia (NH; 3450 m simulated altitude) and (3) Normobaric normoxia (NN). Plasma oxidative stress (malondialdehyde, MDA; advanced oxidation protein products, AOPP) and antioxidant markers (superoxide dismutase, SOD; glutathione peroxidase, GPX; catalase; ferric reducing antioxidant power, FRAP) were measured before and after each exposure. MDA was significantly higher after HH compared to NN condition (+24%). SOD and GPX activities were increased (vs. before; +29% and +54%) while FRAP was decreased (vs. before; −34%) only after 10 h of HH. AOPP significantly increased after 10 h for NH (vs. before; +83%), and HH (vs. before; +99%) whereas it remained stable in NN. These results provide evidence that prooxidant/antioxidant balance was impaired to a greater degree following acute exposure to terrestrial (HH) vs. simulated altitude (NH) and that the chamber confinement (NN) did likely not explain these differences.
The characterization and identification of proteolytic bacteria from the gut of the velvetbean caterpillar (Anticarsia gemmatalis) were the objectives of this study. Twelve aerobic and anaerobic ...isolates of proteolytic bacteria were obtained from the caterpillar gut in calcium caseinate agar. The number of colony forming units (CFUs) of proteolytic bacteria was higher when the bacteria were extracted from caterpillars reared on artificial diet rather than on soybean leaves (1.73 ± 0.35 × 103 and 0.55 ± 0.22 × 103 CFU/mg gut, respectively). The isolated bacteria were divided into five distinct groups, according to their polymerase chain reaction-restriction fragment-length polymorphism profiles. After molecular analysis, biochemical tests and fatty acid profile determination, the bacteria were identified as Bacillus subtilis, Bacillus cereus, Enterococcus gallinarum, Enterococcus mundtii, and Staphylococcus xylosus. Bacterial proteolytic activity was assessed through in vitro colorimetric assays for (general) proteases, serine proteases, and cysteine proteases. The isolated bacteria were able of hydrolyzing all tested substrates, except Staphylococcus xylosus, which did not exhibit serine protease activity. This study provides support for the hypothesis that gut proteases from velvetbean caterpillar are not exclusively secreted by the insect cells but also by their symbiotic gut bacteria. The proteolytic activity from gut symbionts of the velvetbean caterpillar is suggestive of their potential role minimizing the potentially harmful consequences of protease inhibitors from some of this insect host plants, such as soybean, with implications for the management of this insect pest species.
Bacteria colonies from gut homogenates of fifth instar velvetbean caterpillars (Lepidoptera: Noctuidae) were subjected to antibiotic sensitivity experiments using discs containing 22 antibiotics. The ...antibiotic tetracycline provided the best results, followed by chloramphenicol. Tetracycline also provided higher inhibition of colony forming units than chloramphenicol and was therefore provided to the caterpillars in increasing diet concentrations to assess the contribution of gut bacteria to their digestion and development. The activity of proteases (general), serine-proteinases and lipases were significantly suppressed by tetracycline. Concentration–inhibition curves were successfully established for tetracycline and this antibiotic was effective in suppressing them, particularly serine-proteinases, suggesting that gut bacteria may significantly contribute with lipid- and mainly protein-digestion in velvetbean caterpillars. Increased diet concentrations of tetracycline led only to mild increase in insect mortality (
ca. 20%), with the surviving insects showing faster development (≤4 days) and higher pupa weight (<0.04
mg) with increased concentrations of tetracycline. Therefore, the gut bacteria inhibited by tetracycline does not seem to play a crucial role in the survival and development of the velvetbean caterpillar, but may be important in the adaptation of this pest species to hosts rich in protease inhibitors, such as soybean.
Geant4 is the main software tool for Monte Carlo simulations of the calorimeter response in high energy physics (HEP). In this work, we report recent developments of Geant4 physics models, which are ...available in version 10.6, released in December 2019. The main directions of Geant4 developments are discussed: improvements of physics model accuracy, technical modifications to increase CPU performance, and user interface extensions. It is expected that, due to these developments, the simulated responses of electromagnetic and hadronic calorimeters will be slightly affected; validation results from thin-target as well as calorimeter benchmarks will be discussed. New options are introduced in Geant4 allowing to speed up the simulation. We provide recommendations to users on how they may optimize the simulations of their detectors using the new Geant4 interfaces. We will also discuss the role of Birks corrections on the simulation of calorimeter response.
Geant4 developments and applications Allison, J.; Amako, K.; Apostolakis, J. ...
IEEE transactions on nuclear science,
02/2006, Letnik:
53, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Geant4 is a software toolkit for the simulation of the passage of particles through matter. It is used by a large number of experiments and projects in a variety of application domains, including ...high energy physics, astrophysics and space science, medical physics and radiation protection. Its functionality and modeling capabilities continue to be extended, while its performance is enhanced. An overview of recent developments in diverse areas of the toolkit is presented. These include performance optimization for complex setups; improvements for the propagation in fields; new options for event biasing; and additions and improvements in geometry, physics processes and interactive capabilities
It is expected that charmed particles will be copiously produced at Future Circular Collider (FCC). Due to relatively long lifetimes of the particles, it will be necessary to consider their ...interactions with the surrounding materials and materials of the detector. To satisfy these requirements, charmed particle production in soft interactions is studied using the QGS and FTF models of the Geant4 package. Details of these studies are considered in this work.
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