• BMB Reports
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• v.38 no.3
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• pp.328-333
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• 2005

A human homologue of Sar1, named Sara2, was shown to be preferentially expressed during erythropoiesis in a culture stimulated by EPO. Previous studies, in yeast, have shown that secretion-associated and Ras-related protein (Sar1p) plays an essential role in protein transport from the endoplasmic reticulum to the Golgi apparatus. Here, we report the molecular analysis of Sara2 in erythroid cell culture. A 1250 bp long cDNA, encoding a 198 amino-acid protein very similar to Sar1 proteins from other organisms, was obtained. Furthermore, we also report a functional study of Sara2 with Real-time quantitative PCR analysis, demonstrating that expression of Sara2 mRNA increases during the initial stages of erythroid differentiation with EPO and that a two-fold increase in expression occurs following the addition of hydroxyurea (HU). In K562 cells, Sara2 mRNA was observed to have a constant expression and the addition of HU also up-regulated the expression in these cells. Our results suggest that Sara2 is an important gene in processes involving proliferation and differentiation and could be valuable for understanding the vesicular transport system during erythropoiesis.

• Wind and Structures
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• v.10 no.3
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• pp.287-300
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• 2007

Wind action is a factor of fundamental importance in the structural design of light or slender constructions. Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by meteorological phenomena such as Extratropical Storms (EPS) or Tropical Storms. Wind effects due to other phenomena, such as thunderstorms, and its combination with EPS winds in so-called squall lines, are simply neglected. In this paper a model that describes the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS) is proposed. The model is based on a semi empirical representation of an axially-symmetrical flow line pattern that describes a stationary field, modulated by a function that accounts for the evolution of the wind velocity with time. The model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters employed in the model are related to meteorological variables, which are susceptible of statistical assessment. A background wind is also considered, in order to account for the translational velocity of the thunderstorm, normally due to local wind conditions. When the translation of the TS is caused by an EPS, a squall line is produced, causing the highest wind velocities associated with TS events. The resulting vertical velocity profiles were also studied and compared with existing models, such as the profiles proposed by Vicroy, et al. (1992) and Wood and Kwok (1998). The present model predicts horizontal velocity profiles that depend on the distance to the storm center, effect not considered by previous models, although the various proposals are globally compatible. The model can be applied in any region of interest, once the relevant meteorological variables are known, to simulate the excitation due to TS winds in the design of transmission lines, long-span crossings, cable-stayed bridges, towers or similar structures.

• Journal of Magnetics
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• v.12 no.3
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• pp.97-102
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• 2007

We have investigated the electronic structures and magnetism of a full Heusler alloy $Co_2CrGa(001)$ surface by using the all-electron full-potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA). We considered two types of different terminations: the Co-terminated (Co-Term) and the CrGa-terminated (CrGa-Term) surfaces. From the calculated layer-projected density of states (LDOS), we found that the surface of the CrGa-Term shows nearly half-metallic character while that of the Co-Term is far from the half-metallic. For the Co-Term, the surface Co atom moves down to the bulk region by $0.05{\AA}A$, while the subsurface Cr and Ga atoms move up to the surface layer by 0.05 and $0.01{\AA}$, respectively. For the CrGa-Term, there is a large inward relaxation of the surface Ga atom $(0.07{\AA})$, but the relaxation of the surface Cr atom is very small $(0.01{\AA})$. The relaxations affect not much to the overall shapes of DOS for both terminations, but make the surface states of the surface Cr and Ga atoms for the CrGa-Term shift to higher energy that enhances the nearly half-metallic character of the CrGa-Term. The magnetic moments of the surface $Cr(2.98{\mu}_B)$ in the CrGa-Term and the surface $Co(1.17{\mu}_B)$ in the Co-Term were much increased compared to those of the inner-layers $(1.79\;and\;0.77{\mu}_B)$, respectively, while that of the subsurface Cr atom in the Co-Term was decreased to $1.19{\mu}_B$.

• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.1-5
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• 2015

The Unmanned Air Vehicle (UAV) systems are indispensable tools of air surveillance and reconnaissance nowadays. Via this systems, hazardous end risky intelligence gathering activities are handled easily. Although they are named as "Unmanned" the UAV systems are commanded by pilots/operators. So, because of weather conditions, enemy attacks etc. as well as pilot error it is possible to face with sudden Round per Minute (RPM) drops and subsequently engine cut/stop during a mission flight at high altitudes. In this case, there are some very urgent decisions to make and rapid "emergency procedure" steps to take in a very short time before Line of Sight (LOS) is lost. The time before crash and the distance to landing air base need to be calculated, the Return Home route need to be checked and the landing/crash side need to be determined. Therefore it is a vital necessity that UAV pilots have some extra qualifications like being determined, well instructed and trained, experienced apart from operating ability. Within this scope, for an education process of a UAV pilot experience sharing and lessons learned are as important as simulators even more. By means of lessons learned it is possible to find out the reasons, mistakes and prevent the likely UAV accidents. In this study it is told about a real UAV crash, experienced of the pilot, the dos and don'ts and the difficulties. Thus it is aimed to help the people who can experience the same or similar situations in future.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.3
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• pp.231-238
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• 1995

The scapular flap, described by dos Santos in 1986, has been used successfully for the reconstruction of a variety of defects of oro-mandible. Some have defined the gross and vascular anatomy of the lateral border of the scapula, yet useful anatomical information and a complete description of area and contour of each cut surface of lateral border of scapula, which is very important for esthetic and functional reconstruction using dental implants, are missing. These prompted us to clarify the cross-sectional area of lateral border of scapula. Twenty three scapulas of 15 fixed adult Caucasian cadavers were sectioned in every 1cm interval along the lateral border of scapular, and the metric relations and the shape of cut surface were assessed. The lateral border of the scapula, consisting of cortico-cancellous bone measuring $7.86{\pm}0.97mm$ in width, $19.6{\pm}2.86mm$ in height and $12{\pm}1.78cm$ in length, could be harvested as an osteocutaneous scapular flap or as a single vascularized bone flap. The mean thickness of cortical bone of lateral, medial, dorsal and costal surface was $0.46{\pm}1.48mm$, $1.78{\pm}1.34mm$, $1.54{\pm}1.11mm\;and\;1.35{\pm}0.87mm$, respectively. So we have thought that all scapular transplants could be supported osseointegrated implants for fixation of dental prosthesis.

• Journal of the Korean Magnetics Society
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• v.16 no.2
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• pp.111-114
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• 2006

We investigated the magnetism and electronic structures for the layered structures consisting of (110) layers of zinc-blende CrAs and MnAs. We calculated the electronic structures for $(CrAs)_3(MnAs)_3(110)$ superlattice consisted of alternating three layers of CrAs(110) and MnAs(110) by the full-potential linearized augmented plane wave (FLAPW) method. The calculated magnetic moment of Cr in interface layer ($3.07\;\mu_B$) was slightly larger than that of Cr atom in center layer ($3.06\;\mu_B$), while that of interface Mn atom ($3.74\;\mu_B$) was slightly smaller than the value of Mn atom in center layer ($3.76\;\mu_B$). The electronic structure and half-metallicity in this superlattice were discussed using the calculated density of states.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.266-271
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• 2009

In the recently synthesized rare earth transition metal carbide $La_7O_{s4}C_9$ one finds one-dimensional organometallic $[O_{s4}C_9]^{21-}$ polymers embedded in a $La^{3+}$ ionic matrix. The electronic structure of the polymeric $[O_{s4}C_9]^{21-}$ chain was investigated by density of states (DOS) and crystal orbital overlap population (COOP), using the extended Huckel algorithm. A fragment molecular orbital analysis is used to study the bonding characteristics of the $C_2$ units in $La_7O_{s4}C_9$ containing $C_2$ units and single C atoms as well. The title compound contains partially filled Os and carbon bands leading to metallic conductivity. As the observed distances already indicated, the calculations show extensive Os-C interactions. The C-C bond distance in the diatomic $C_2$ units ($d_{C-C}$=131 pm) in the solid is significantly increased relative to $${C_2}^{2-}$$ or acetylene, because antibonding $1{\pi}_g$ orbitals are partially filled by the Os-$C_2(1\;{\pi}_g)$ bonding contribution found at and below the Fermi level.

• Journal of the Korean Geophysical Society
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• v.4 no.3
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• pp.145-162
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• 2001

With the rapid advance of internet service and the corresponding migration of service environment from the text-based one to WWW (World Wide Web) environment, the number of internet users is growing rapidly due to its easy usage. Accordingly, usage of internet as services for sending electronic mails to the other patry over the network is becoming increasingly prevalent. Web-based electronic mailing system is comprised of a server and a client The former provides the users with e-mail accounts and services, while the latter serves as a user interface. In other words, it enales those public users who dos not own e-mail accounts on the existing mail server to have an access to hte mailing service through the web. In this paper, we designed a effective web-based electronic mailing system which is based on the internet explorer and linux operating system, which overcomes limitations of the existing e-mail systes and this facilitates the development of a stable e-mail system by being able to avoiding the low system performance due to the bursty characteristics of e-mail messages and the increasing number of users.

• Journal of Gastric Cancer
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• v.16 no.1
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• pp.14-20
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• 2016

Purpose: Early diagnosis of gastric cancer is still the exception in Western countries. In the East, as in Japan and Korea, this disease is an endemic disorder. More conservative surgical procedures are frequently performed in early gastric cancer cases in these countries where sentinel lymph node navigation surgery is becoming a safe option for some patients. This study aims to evaluate preliminary outcomes of patients with early gastric cancer who underwent sentinel node navigation surgeries in Brazil, a country with non-endemic gastric cancer levels. Materials and Methods: From September 2008 to March 2014, 14 out of 205 gastric cancer patients underwent sentinel lymph node navigation surgeries, which were performed using intraoperative, endoscopic, and peritumoral injection of patent blue dye. Results: Antrectomies with Billroth I gastroduodenostomies were performed in seven patients with distal tumors. The other seven patients underwent wedge resections. Sentinel basin resections were performed in four patients, and lymphadenectomies were extended to stations 7, 8, and 9 in the other 10. Two patients received false-negative results from sentinel node biopsies, and one of those patients had micrometastasis. There was one postoperative death from liver failure in a cirrhotic patient. Another cirrhotic patient died after two years without recurrence of gastric cancer, also from liver failure. All other patients were followed-up for 13 to 79 months with no evidence of recurrence. Conclusions: Sentinel lymph node navigation surgery appears to be a safe procedure in a country with non-endemic levels of gastric cancer.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.3
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• pp.482-488
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• 2009

Mobile Ad-hoc Networks provide communication without a centralized infrastructure, which makes them suitable for communication in disaster areas or when quick deployment is needed. On the other hand, they are susceptible to malicious exploitation and have to face different challenges at different layers due to its open Ad-hoc network structure which lacks previous security measures. Denial of service (DoS) attack is one that interferes with the radio transmission channel causing a jamming attack. In this kind of attack, an attacker emits a signal that interrupts the energy of the packets causing many errors in the packet currently being transmitted. In harsh environments where there is constant traffic, a jamming attack causes serious problems; therefore measures to prevent these types of attacks are required. The objective of this paper is to carry out the simulation of the jamming attack on the nodes and determine the DoS attacks in OPNET so as to obtain better results. We have used effective anomaly detection system to detect the malicious behaviour of the jammer node and analyzed the results that deny channel access by jamming in the mobile Ad-hoc networks.