Heavy Quark Production at the TESLA Collider and its Sensitivity to the Gluon Content in Photon

Heavy quark production is studied at the high energy linear e^+e^- collider (LC) TESLA both in its nominal and Photon Collider (PC) mode. Leading order cross-sections are calculated for the production of heavy quarks, e^+e^- -> e^+e^- Q\bar{Q}X, at high transverse momenta. The sensitivity of this process to the gluon content in the photon is studied.Comment: 16 pages, Latex, 10 ps figures, uses epsfig.sty. IFT 2001/3

ERS international congress, Madrid, 2019: Highlights from the Epidemiology and Environment Assembly

At the European Respiratory Society's International Congress of 2019, which was held in Madrid, Spain, there were several sessions with exciting poster and oral presentations within the fields of epidemiology and tobacco control. This article is the summary of two of these sessions. One was on the use of Big Data in epidemiology and the other, on the global burden of respiratory disease and tobacco

Shuttle/spacelab MMAP/electromagnetic environment experiment phase B definition study

Progress made during the first five months of the Phase B definition study for the MMAP/Electromagnetic Environment Experiment (EEE) was described. An antenna/receiver assembly has been defined and sized for stowing in a three pallet bay area in the shuttle. Six scanning modes for the assembly are analyzed and footprints for various antenna sizes are plotted. Mission profiles have been outlined for a 400 km height, 57 deg inclination angle, circular orbit. Viewing time over 7 geographical areas are listed. Shuttle interfaces have been studied to determine what configuration the antenna assembly must have to be shared with other experiments of the Microwave Multi-Applications Payload (MMAP) and to be stowed in the shuttle bay. Other results reported include a frequency plan, a proposed antenna subsystem design, a proposed receiver design, preliminary outlines of the experiment controls and an analysis of on-board and ground data processing schemes

Debye mass and heavy quark potential in a PNJL quark plasma

We calculate the Debye mass for the screening of the heavy quark potential in a plasma of massless quarks coupled to the temporal gluon background governed by the Polyakov loop potential within the PNJL model in RPA approximation. We give a physical motivation for a recent phenomenological fit of lattice data by applying the calculated Debye mass with its suppression in the confined phase due to the Polyakov-loop to a description of the temperature dependence of the singlet free energy for QCD with a heavy quark pair at infinite separation. We compare the result to lattice data.Comment: 6 pages, 1 figure, contribution to Proceedings of the 6th International Conference on "Critical Point and Onset of Deconfinement", to appear in Phys. At. Nucl., vol. 7

Taxonomy of the wild species of genus Crataegus (Rosaceae): An updated review for the flora of Nakhchivan Autonomous Republic (Azerbaijan)

We clarified the current state of genus Crataegus L. in the flora of the Nakhchivan Autonomous Republic (Azerbaijan) using a comparative analysis of herbarium specimens from the Azarbaijan herbariums and data collected during the expeditions in 2004–2018. We succeed in adding some important data on the flora of Nakhchivan Autonomous Republic and Azerbaijan, we also enhanced the previous research with chromosome and morphological analysis. We identified 17 wild species of Crataegus genus in the Nakhchivan Autonomous Republic (C. pentagyna Waldst. et Kit. ex Willd., 1800, C. zangezura Pojark., 1939, C. orientalis Pall. ex Bieb., 1808, C. pojarkoviae Kossych, 1964, C. tournefortii Griseb., 1843, C. szovitsii Pojark., 1939, C. pontica C. Koch, 1853, C. meyeri Pojark., 1939, C. eriantha Pojark., 1939, C. atrosanguinea Pojark., 1939, C. caucasica C. Koch, 1853, C. pallasii Griseb., 1843, C. rhipidophylla Gand. (С. curvisepala Lindm.; C. kyrtostyla Pojark.) 1871, C. pseudoheterophylla Pojark., 1939, C. monogyna Jacq., 1775, C. x armena Pojark., 1939, and C. x cinovskisii Kassumova), which will contribute to five introduced cultural species used in the greenery. We also clarified the status of interserial and intersection hybrids using the chromosome and morphological analysis. The article includes the complete list of Crataegus L. species with information about synonyms of the species, patterns of distribution, habitat, latitude and elevation, flowering and fruiting phenology

Optoelectronic comb generation and cross-injection locking of photonic integrated circuit for millimetre-wave generation

We demonstrate how a monolithically integrated heterodyne source was used for a 33.6 GHz signal generation using an optical solution by a combination of cross-optical injection locking inside the chip and electrical injection locking at the RF signal 7th sub-harmonic

On the number of solutions of a transcendental equation arising in the theory of gravitational lensing

The equation in the title describes the number of bright images of a point source under lensing by an elliptic object with isothermal density. We prove that this equation has at most 6 solutions. Any number of solutions from 1 to 6 can actually occur.Comment: 26 pages, 12 figure

Types of coeliac trunk branching including accessory hepatic arteries: a new point of view based on cadaveric study

Background: The coeliac trunk (CT) is major visceral branch of the abdominal aorta. Familiarity with anatomic variations of the CT is relevant for planning radiological and surgical procedures. The aim of our research was determining variations of the CT, including the occurrence of accessory hepatic arteries (AHA). Materials and methods: Forty cadavers were studied. Six patterns of CT branching were observed in this study. AHA were observed in 7 (17.5%) specimens. The most prevalent variation was normal trifurcation, accounting for 62.5% of cases. The rarest variation was absence of the CT, with an incidence of 2.5%. In this variant the left gastric artery, the common hepatic artery, and the splenic artery branched directly off the abdominal aorta. Results: The study material allowed to distinguish two CT branching patterns which, to the best of our knowledge, have not been reported before. It was a type with four branches originating from the CT: the left gastric artery, the common hepatic artery, the splenic artery, and right AHA. The other previously unreported pattern variant was the CT which gave off three branches: the common hepatic artery, the splenic artery and right AHA. Conclusions: The average distance between the aortic hiatus and the coeliac trunk calculated for all the cadavers amounted to 54 ± 11.85 mm. The average distance between the CT and the superior mesenteric artery was 11.1 ± 7.7 mm

The appearance potency of gay and straight men’s websites

Gay men's greater body dissatisfaction compared to straight men has been explained as a result of gay men’s more 'appearance potent' subculture. This study aimed to critically appraise this explanation by assessing images of men and women for their physical characteristics and objectification across 8 popular gay and straight men's dating and porn websites. 1,415 images of men and 715 images of women across the website’s main pages were coded. Results showed that the gay men's websites featured more images of men that were appearance-ideal, nude, and sexualized in comparison to the straight men's websites. With the converse true for straight men’s websites. These results highlight the continuing need to develop and provide interventions that critique the appearance potency of popular media, particularly so for gay men

The enzymatic activity of the VEGFR2-receptor for the biosynthesis of dinucleoside polyphosphates

The group of dinucleoside polyphosphates encompasses a large number of molecules consisting of two nucleosides which are connected by a phosphate chain of variable length. While the receptors activated by dinucleoside polyphosphates as well as their degradation have been studied in detail, its biosynthesis has not been elucidated so far. Since endothelial cells released the dinucleoside polyphosphate uridine adenosine tetraphosphate (Up4A), we tested cytosolic proteins of human endothelial cells obtained from dermal vessels elicited for enzymatic activity. When incubated with ADP and UDP, these cells showed increasing concentrations of Up4A. The underlying enzyme was isolated by chromatography and the mass spectrometric analysis revealed that the enzymatic activity was caused by the vascular endothelial growth factor receptor 2 (VEGFR2). Since VEGFR2 but neither VEGFR1 nor VEGFR3 were capable to synthesise dinucleoside polyphosphates, Tyr-1175 of VEGFR2 is most likely essential for the enzymatic activity of interest. Further, VEGFR2-containing cells like HepG2, THP-1 and RAW264.7 were capable of synthesising dinucleoside polyphosphates. VEGFR2-transfected HEK 293T/17 but not native HEK 293T/17 cells synthesised dinucleoside polyphosphates in vivo too. The simultaneous biosynthesis of dinucleoside polyphosphates could amplify the response to VEGF, since dinucleoside polyphosphates induce cellular growth via P2Y purinergic receptors. Thus the biosynthesis of dinucleoside polyphosphates by VEGFR2 may enhance the proliferative response to VEGF. Given that VEGFR2 is primarily expressed in endothelial cells, the biosynthesis of dinucleoside polyphosphates is mainly located in the vascular system. Since the vasculature is also the main site of action of dinucleoside polyphosphates, activating vascular purinoceptors, blood vessels appear as an autocrine system with respect to dinucleoside polyphosphates. We conclude that VEGFR2 receptor is capable of synthesising dinucleoside polyphosphates. These mediators may modulate the effects of VEGFR2 due to their proliferative effects