378 research outputs found
Phenology and Ripening of Vitis vinifera L. and Vitis labrusca L. Varieties in the Maritime Climate of Samsun in Turkeyâs Black Sea Region
Heavy rainfall in Turkeyâs northern Black Sea Region in spring and autumn, combined with insufficientsunshine during the vegetation period, results in poor ripening of European grape (Vitis vinifera L.)cultivars. Compared to other coastal provinces in the Central and Eastern Black Sea Region, Samsunreceives relatively little rainfall. This study evaluated the adaptation of Vitis vinifera L. and Vitis labruscaL. grapes to Samsun by examining the phenology and ripening characteristics of these cultivars in2010 and 2011 and calculating climatic indices using long-term data for Samsun in order to assess thepotential for viticulture in the area. The following climatic characteristics were identified: annual sunshineduration, 1 836 hours; Branas Heliothermic Index (BHI), 3.0; Hydrothermic Index (HyI), 4 053.7°C mm;Winkler Index (WI growing degree days) 1 832/Region III âWarmâ; and Huglin Index (HI) 1 978°C/HI-1âTemperateâ. Phenological cycles (budburst to harvest) varied between 120 and 176 days, with TrakyaĂ°lkeren and Yalova Ă°ncisi the most precocious varieties and Favli the latest variety in both years. Heatsummation requirements ranged from 1 210 to 1 844 GDD, with Trakya Ă°lkeren requiring the least andNarince the most heat summation. Total soluble solid (TSS) values ranged from 15.1 °Brix (Trakya Ă°lkeren)to 21.4 °Brix (Labrusca). Although Favli was the last to ripen, the TSS value for this variety was only 17.1%.These findings indicate that, with the exception of Favli, all the varieties examined are capable of maturingunder the climatic conditions in the study area, suggesting that the coastal areas of Samsun province aresuitable for early and mid-season Vitis vinifera L. grape viticulture
Marginally low mass ratio close binary system V1191 Cyg
In this study, we present photometric and spectroscopic variations of the
extremely small mass ratio () late-type contact binary system
\astrobj{V1191 Cyg}. The parameters for the hot and cooler companions have been
determined as = 0.13 (1) , = 1.29 (8)
, = 0.52 (15) , = 1.31 (18)
, = 0.46 (25) , = 2.71 (80)
, the separation of the components is = 2.20(8) and
the distance of the system is estimated as 278(31) pc. Analyses of the times of
minima indicates a period increase of
days/yr that reveals a very high mass transfer rate of
/yr from the less massive
component to the more massive one. New observations show that the depths of the
minima of the light curve have been interchanged.Comment: Accepted for publication in New Astronomy, 16 pages, 2 figures, 4
table
Close Binary System GO Cyg
In this study, we present long term photometric variations of the close
binary system \astrobj{GO Cyg}. Modelling of the system shows that the primary
is filling Roche lobe and the secondary of the system is almost filling its
Roche lobe. The physical parameters of the system are , , , , , , and . Our results show that \astrobj{GO
Cyg} is the most massive system near contact binary (NCB). Analysis of times of
the minima shows a sinusoidal variation with a period of years due
to a third body whose mass is less than 2.3. Finally a period
variation rate of d/yr has been determined using all
available light curves.Comment: Accepted for publication in New Astronomy, 18 pages, 4 figures, 7
table
Absolute properties of the binary system BB pegasi
We present ground-based photometry of the low-temperature contact binary BB Peg. We collected all the times of mid-eclipse available in the literature and combined them with those obtained in this study. Analyses of the data indicate a period increase of (3.0 ± 0.1) Ă 10-8 days yr -1. This period increase of BB Peg can be interpreted in terms of the mass transfer 2.4 Ă 10-8 Mâ yr-1 from the less massive to the more massive component. The physical parameters have been determined as Mc = 1.42Mâ, Mh = 0.53 Mâ, Rc = 1.29 Râ, Rh, = 0.83 Râ, Lc = 1.86 Lâ, and L h = 0.94 Lâ through simultaneous solutions of light and of the radial velocity curves. The orbital parameters of the third body, which orbits the contact system in an eccentric orbit, were obtained from the period variation analysis. The system is compared to the similar binaries in the Hertzsprung-Russell and mass-radius diagrams.Ege University Research Fund and TĂBÄ°TAK National Observator
Absolute properties of the binary system BB Pegasi
We present a ground based photometry of the low-temperature contact binary BB
Peg. We collected all times of mid-eclipses available in literature and
combined them with those obtained in this study. Analyses of the data indicate
a period increase of 3.0(1) x 10^{-8} days/yr. This period increase of BB Peg
can be interpreted in terms of the mass transfer 2.4 x 10^{-8} Ms yr^{-1} from
the less massive to the more massive component. The physical parameters have
been determined as Mc = 1.42 Ms, Mh = 0.53 Ms, Rc = 1.29 Rs, Rh = 0.83 Rs, Lc =
1.86 Ls, and Lh = 0.94 Ls through simultaneous solution of light and of the
radial velocity curves. The orbital parameters of the third body, that orbits
the contact system in an eccentric orbit, were obtained from the period
variation analysis. The system is compared to the similar binaries in the
Hertzsprung-Russell and Mass-Radius diagram.Comment: 17 pages, 3 figures, accepted for Astronomical Journa
Use of social networking in the Middle East: student perspectives in higher education
This study aims to determine the benefits, risks, awareness, cultural factors, and sustainability, allied to social networking (SN) use in the higher education (HE) sector in Middle Eastern countries, namely Jordan, Saudi Arabia, and Turkey. Using an online survey, 1180 complete responses were collected and analyzed using the statistical confirmatory factor analysis method. The use of SN in the Middle Eastern HE sector has the capacity to promote and motivate students to acquire professional and personal skills for their studies and future workplace; however, the use of SN by tertiary students is also associated with several risks: isolation, depression, privacy, and security. Furthermore, culture is influenced by using SN use, since some countries shifted from one dimension to another based on Hofstede's cultural framework. The study new findings are based on a sample at a specific point in time within a culture. The study findings encourage academics to include SN in unit activities and assessments to reap the benefits of SN, while taking steps to mitigate any risks that SN poses to students. Although other studies in the Middle East examined the use of Learning Management System and Facebook in, HE as a means of engaging students in discussions and communications, however, this study contributes a better understanding of the benefits and risks, awareness, culture, and sustainability, associated with the use of SN in the HE sector in the Middle East. Finally, the paper concludes with an acknowledgment of the study limitations and suggestions for future research
Presentation and management of keloid scarring following median sternotomy: a case study
<p>Abstract</p> <p>Introduction</p> <p>Keloid scars following median sternotomy are rare and occur more frequently in pigmented skin. Different management strategies have been described with variable success. We present a case of keloid scar formation following cardiac surgery including our management and the final aesthetic result.</p> <p>Case description</p> <p>A 64 year old female of fair complexion underwent mitral valve replacement. The procedure and postoperative recovery were uncomplicated, however, during the following year, thick keloid scars formed over the incision sites. Initial non surgical measures failed to relieve pain and did not offer any tangible aesthetic benefit. Eventually surgical excision was attempted. She presented to our clinic for nine months follow up with significant improvement in pain and aesthetic result.</p> <p>Discussion and Evaluation</p> <p>Several theories have attempted to explore the pathophysiology of keloid scar formation. A number of predisposing factors have been documented however none existed in this case. A variety of invasive and non invasive approaches have been described but significant differences in success rates and methodology of investigations still precludes a standardized management protocol.</p> <p>Conclusions</p> <p>In this case study a rare presentation of keloid scar has been presented. The variety of methods used to improve pain and aesthetic result demonstrates the propensity of keloid scars to recur and the therapeutic challenges that surgeons have to face in their quest for a satisfactory patient outcome.</p
Leading order analysis of neutrino induced dimuon events in the CHORUS experiment
We present a leading order QCD analysis of a sample of neutrino induced
charged-current events with two muons in the final state originating in the
lead-scintillating fibre calorimeter of the CHORUS detector. The results are
based on a sample of 8910 neutrino and 430 antineutrino induced opposite-sign
dimuon events collected during the exposure of the detector to the CERN Wide
Band Neutrino Beam between 1995 and 1998. % with GeV
and GeV collected %between 1995 and 1998. The analysis yields a
value of the charm quark mass of \mc = (1.26\pm 0.16 \pm 0.09) \GeVcc and a
value of the ratio of the strange to non-strange sea in the nucleon of , improving the results obtained in similar analyses
by previous experiments.Comment: Submitted to Nuclear Physics
Associated Charm Production in Neutrino-Nucleus Interactions
In this paper a search for associated charm production both in neutral and
charged current -nucleus interactions is presented. The improvement of
automatic scanning systems in the {CHORUS} experiment allows an efficient
search to be performed in emulsion for short-lived particles. Hence a search
for rare processes, like the associated charm production, becomes possible
through the observation of the double charm-decay topology with a very low
background. About 130,000 interactions located in the emulsion target
have been analysed. Three events with two charm decays have been observed in
the neutral-current sample with an estimated background of 0.180.05. The
relative rate of the associated charm cross-section in deep inelastic
interactions, has been
measured. One event with two charm decays has been observed in charged-current
interactions with an estimated background of 0.180.06 and the
upper limit on associated charm production in charged-current interactions at
90% C.L. has been found to be .Comment: 10 pages, 4 figure
- âŠ