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Öğe Antenna Selection for Decode and Forward Based MIMO Cooperative Networks(IEEE, 2014) Aydin, Erdogan; Ilhan, Haci; Ozdemir, OzgurIn this paper, a cooperative system structure that utilizes decode and forward (DF) method with antenna selection based on the signal to noise ratio (SNR) have been proposed. In order to decrease performance degradation due to error propagations in DF based wireless cooperative networks and increase the error performance of the system, selection combining (SC), classical maximal ratio combining (MRC), cooperative-maximal ratio combining (C-MRC) and link adaptive regeneration (LAR) techniques have been utilized at destination. Error performance analyses of the considered structures are investigated using optimal decision rules determined theoretically for the corresponding relaying strategy.Öğe Differential Modulation Based Network Coded Cooperative Communications(IEEE, 2015) Karabulut, Muhammet Ali; Ilhan, Haci; Ozdemir, OzgurMultiple access relay channel (MARC) where multiple users communicate with a common destination via a relay, is an innovative approach and one of the most important network coding applications in wireless cooperative communications in recent years. In this paper, noncoherent differential binary phase shift keying (DPSK) technique which eliminates the need for channel estimation cost is applied to the MARC system model that uses maximum likelihood detection approach at the common destination. Noncoherent DPSK modulation of the MARC system model provides full diversity gain that has been observed at the resulting Monte-Carlo simulation.Öğe Differential Network Coding in Wireless Networks(IEEE, 2009) Ozdemir, Ozgur; Yilmaz, Ali OzgurIn this paper a three-terminal communication scenario where two users exchange information by employing differential binary modulation and network coding via a relay is considered. The transmission is divided into three slots in time where the first and second slots are allocated to the transmission of differential encoded data of the users. After demodulation, the relay broadcasts the bit-wise XOR-ed and differential encoded pocket to the users in the third slot. The optimum detector and a simplified decision algorithm are derived based on the maximum likelihood rule. The numerical results for Rayleigh fading show that both of the proposed algorithms provide full diversity order. The simulations also demonstrate that the proposed differential network coded transmission not only offers a sum-rate gain of up to 4/3 compared to classical bi-directional relaying with four communication slots but also provides better BER performance as the signal to noise ratio increases.Öğe Dog massacre with pesticide for theft: Methomyl poisoning(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2019) Ozdemir, Ozgur; Ates, Mehmet Burak; Ortatatli, Mustafa; Terzi, Funda; Avci, Tulay; Hatipoglu, Fatih; Ciftci, Mustafa KemalIn this case report, acute methomyl poisoning in dogs is described by pathological and toxicological findings for the first time in Turkey. Five of the thirty stray dogs that were found dead within 1-2 days after eating the foodstuffs in an industrial area in Konya were necropsied. Grossly, undigested pieces of chicken meat with a mild insecticidal smell in stomach of all dogs were found and toxicological analysis by GC-MS revealed toxic levels of methomyl in the stomach contents (15.7-17.8 ppm) and, intestines, livers and kidneys (1.2-2.9 ppm) also. In addition, histopathologically degenerative and necrotic changes were observed in liver, brain, lung, kidneys and gastrointestinal system mucosa. Postmortem and histopathological examinations and toxicological analyses revealed that deaths were related to methomyl poisoning and it has been subsequently learned from the police officers and printed media that this poison had been deliberately infected to dog food for the purpose of theft committed in the industrial area. Publishing these intentional poisoning events, we have wanted to draw attention to that more serious measures and statutory regulations should be taken by governments about animal rights.Öğe Effect of Acticoat (R) and Cutinova Hydro (R) on wound healing(WILEY-BLACKWELL, 2013) Arican, Mustafa; Hatipoglu, Fatih; Uyaroglu, Aysen; Ozdemir, Ozgur; Ozkan, KadircanIn this study, the effects of the wound-covering materials, Acticoat((R)) and Cutinova Hydro((R)), on wound healing have been studied in rabbit models with open and tissue-lost wounds with full-thickness flank excisions. Rabbits were used as subjects with three groups of four rabbits each, and trial periods of 7, 14 and 21{\uns}days. Four circular wounds, of 1.5 cm diameter were made two on the right (one of them control) and two on the left (one of them control) of the dorsal sides of the abdomen. Acticoat((R)) and Cutinova Hydro((R)) were applied on the wounds with suture for a period of 21 days and one each placed on the right and left sides as control with gauze. Biopsy specimens were taken from the animals at the end of the research period to check the length of the epithelium, epithelial thickness, size of wounds, wound granulation tissue formation and histopathological evaluation for clarity. The Acticoat((R)) group showed better healing and scar formation compared to the Cutinova Hydro((R)) group by macroscopic examination. Epithelial wound length and clarity in terms of statistical difference occurred on day 21 (P <0.05); while the length of the wound epithelium decreased patency, epithelial thickness on days similar to 7, 14 and 21, showed no statistical differences (P >0.05). As a result, the Acticoat((R)) wound dressing was determined as a more reliable for the early wound healing. This study has shown the short-term clinical benefits of hydroactive, polyurethane dressings in the management of acute wounds. However, longer periods of wound healing procedure should be planned for reliable and safe results of wound dressing. It has also been concluded that microbiological analyses should be included for more robust and reliable comparisons.Öğe Effect of Asiaticoside, Collagenase, and Alpha-chymotrypsin on Wound Healing in Rabbits(H M P COMMUNICATIONS, 2016) Ozdemir, Ozgur; Ozkan, Kadircan; Hatipoglu, Fatih; Uyaroglu, Aysen; Arican, MustafaWound dressing materials such as asiaticoside, collagenase, and alpha-chymotrypsin are often used for effective wound healing activity. Objectives.' In this study; the effects of asiaticoside,, collagenase, and alpha-chymotrypsin were studied in rabbit models with open wounds with tissue loss and with full-thickness flank excisions for a period of 21 days, Materials and Methods. Three groups of 4 rabbits were examined during trial periods of 7, 14, and 21 days. Four circular wounds measuring 1.5 cm in diameter were made on the dorsal sides of the animals: 2 on the right and 2 the left. Asiaticoside, collagenase, and alpha-chymotrypsin were applied to wounds daily for a period of 7, 14, and 21 days, while 1 gauzed wound served as the control. All biopsy specimens were histopathologically evaluated for recovery. On day 7, microscopic review showed no differences in wound healing between groups. Results. By day 14, alpha-chyrnotrypsin showed the quickest reepithelialization (P<0.05); and by day 21 asiaticoside and collagenase (P<0.01) showed effective recovery, due to the completion of wound healing for all animals in both groups. Conclusion. Alpha-chymotrypsin is more effective than the other 2 groups for only 14 days. The effectiveness of asiaticoside and collagenase-displayed a more rapid improvement in comparison to alpha-chymotrypsin for healing open wounds with tissue loss for a period of 21 days.Öğe The Effect of Co-channel Interference in DF Based MARC System with Relay Selection(IEEE, 2017) Karabulut, Muhammet Ali; Aslan, Hayri; Ozdemir, Ozgur; Ilhan, HaciNetwork coding has recently received significant attention as an innovative approach to improve the throughput of wireless communication systems. The multiple access relay channel (MARC), in which multiple users communicate with a common destination via relays, is one of the important network coding applications for wireless cooperative communications. In this paper, the effect of co-channel interference in decode-and forward (DF) based MARC model with relay selection is investigated by obtaining the average bit error rate (BER) results of the proposed system for cascaded Rayleigh fading channels. The simulation results obtained by using binary phase shift keying (BPSK) modulation have shown that the proposed system overcome diversity gain reduction due to error propagation, and detrimental effects of the co-channel interference.Öğe The Effectiveness of Anti-R. equi Hyperimmune Plasma against R. equi Challenge in Thoroughbred Arabian Foals of Mares Vaccinated with R-equi Vaccine(HINDAWI LTD, 2014) Erganis, Osman; Sayin, Zafer; Hadimli, Hasan Huseyin; Sakmanoglu, Asli; Pinarkara, Yasemin; Ozdemir, Ozgur; Maden, MehmetThis study aimed to determine the effectiveness of a pregnant mare immunization of a Rhodococcus equi (R. equi) vaccine candidate containing a water-based nanoparticle mineral oil adjuvanted (Montanide IMS 3012) inactive bacterin and virulence-associated protein A (VapA), as well as the administration of anti-R. equi hyperimmune (HI) plasma against R. equi challenge in the mares' foals. The efficacy of passive immunizations (colostral passive immunity by mare vaccination and artificial passive immunity by HI plasma administration) was evaluated based on clinical signs, complete blood count, blood gas analysis, serological response (ELISA), interleukin-4 (IL-4) and interferon gamma (IFN-gamma), total cell count of the bronchoalveolar lavage fluids (BALF) samples, reisolation rate of R. equi from BALF samples (CFU/mL), lung samples (CFU/gr), and lesion scores of the organs and tissue according to pathological findings after necropsy in the foals. The vaccination of pregnant mares and HI plasma administration in the foals reduced the severity of R. equi pneumonia and lesion scores of the organs and tissue by 3.54-fold compared to the control foals. This study thus indicates that immunization of pregnant mares with R. equi vaccine candidate and administration of HI plasma in mares' foals effectively protect foals against R. equi challenge.Öğe Efficacy of experimental inactivated and live Rhodococcus equi vaccines for thoroughbred Arabian mares in mice(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2015) Erganis, Osman; Hadimli, Hasan Huseyin; Sayin, Zafer; Sakmanoglu, Asli; Pinarkara, Yasemin; Ozdemir, OzgurThe aim of this study was to determine the efficacy of inactive Rhodococcus equi vaccine candidates included that bacterin+aluminum hydroxide Al(OH)(3)), bacterin+VapA+(Al(OH)(3)), bacterin+Montanide IMS 3012 (IMS), bacterin+ VapA+IMS, and live vaccine using mice as a model. The efficacy of vaccine was evaluated according to clinical findings, humoral and cellular immunity (levels of INF-g and IL-4), and results of microbiological culture from internal organs in dead or sacrificed mice. Inactive R. equi vaccines were subcutaneously administered to mice three times at 15-day intervals and live vaccine was intraperitoneally injected once. Fifteen days after the last vaccination, aerosol challenges were carried out with the pathogenic R. equi VapA(+)K2002 strain in all groups. Two mice were sacrificed from each challenge groups on days 1, 3, 5, and 7. The antibody titers of vaccinated mice were found to be significantly higher than those of the controls. The largest number of INF-g positive samples were detected in the bacterin+ VapA+IMS and bacterin+ IMS groups. IL-4 positivity was determined only in live vaccine groups. The lowest reisolation rate of R. equi from internal organs was observed in the bacterin+VapA+IMS group. It was concluded that R. equi vaccines, and especially bacterin+VapA+IMS, are useful to protect mice against R. equi infection.Öğe Exact BER Performance Analysis of Incremental Relaying over Rayleigh Fading Channels(IEEE, 2016) Ozdemir, OzgurBecause of the half-duplex constraint of current radio terminals, the spatial diversity gains promised by wireless cooperative communication protocols are obtained at the cost of spectral efficiency loss increasing with the number of cooperative terminals. Incremental relaying is among the most popular techniques to provide improvement in throughput of the cooperative systems by exploiting limited feedback from the destination which decreases the total number of required re-transmissions from the intermediate nodes. In this paper, the exact bit error rate performance analysis of a signal-to-noise ratio based incremental digital relaying scheme is proposed over Rayleigh fading channels with binary phase shift keying modulation.Öğe Exact BER Performance Analysis of Link Adaptive Relaying with Noncoherent BFSK Modulation(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2014) Ozdemir, OzgurLink adaptive relaying (LAR) is one of the most popular techniques developed for mitigating error propagation in decode and forward (DF) based cooperative wireless networks which employs soft power scaling approaches at the relay nodes. On the other side, frequency shift keying (FSK) is a prominent technique for eliminating the need for channel estimation by training sequences which increases complexity of the system and causes reduction in the transmission rate in proportional to the number of users involved in the network. In this paper, performance of an LAR scheme with noncoherent binary FSK (BFSK) signaling is investigated by deriving exact closed form bit error rate expressions in Rayleigh fading channels.Öğe Generalized reactive amyloidosis in a gazelle (gazella gazella)(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2013) Ozdemir, Ozgur; Hatipoglu, Fatih; Karaman, MusaThis report was described generalized amyloidosis in a male gazelle, 1.5 years old. In necropsy, hyperaemia on all the serosal surfaces in abdomen, a hemorrhagic ulcer, 7 cm in diameter, on mucosa of rumen, and whitish colored foci, 1-2 mm diameter, on the surfaces of both kidneys were present. Microscopically, there were homogenous pink depositions in the glomeruli, intertubular interstitium, tubular basement membranes and walls of blood vessel in kidney, lymphoid follicles in spleen, space of Disse in liver and lamina propria of the small intestine. These deposits were seen brick-red color stained with Congo red on tissue sections, but these were not stained with Congo red after treated with potassium permanganate. For this reason, AA (secondary) amyloidosis was evaluated. When stock tissue samples stored in 10% formalin were treated with Lugol and acid sulphuric, amyloid depositions were seen as dark blue. Generalized reactive amyloidosis with ulceration in the rumen was diagnosed. Amyloid deposits in the tissues are not only fresh tissue but also tissue stored formalin can be determined as a macroscopic.Öğe Halofuginone may suppresses azoxymethane-induced serum tumor necrosis factor-a synthesis and aberrant crypt foci progression in rat colon(AGRICULTURAL RESEARCH COMMUNICATION CENTRE, 2017) Corum, Orhan; Ozdemir, Ozgur; Yazar, EnverThe aim of this research was to investigate the effect of halofuginone on the progression of azoxymethane-induced colon cancer in rats. A total of 38 male Wistar albino rats were divided into 4 groups: Control (n=8), Halofuginone (n= 10, 0.4 mg/kg, PO, SID), Cancer (n=10, azoxymethane, 15 mg/kg, IP, once a week for two weeks) and Cancer + Halofuginone (n=10). After 18 weeks, blood samples were taken under anesthesia and all animals were sacrificed. Aberrant crypt foci in the colon were stained with methylene blue. Blood cytokines, thiobarbituric acid reactive substances, 13,14-dihydro-15-ketoprostaglandin F2 alpha levels, hemogram and biochemical values were measured. The tumor necrosis factor-a level in the Cancer group was higher (P<0.05) than in other groups, while higher numbers of aberrant crypt foci were found in the Cancer group compared with the Cancer + Halofuginone group (P<0.05). In summary, it may be stated that halofuginone may warrant evaluation as a supportive drug in the treatment of colon cancer in the future.Öğe Hemorrhagic bowel syndrome in a holstein cow - case report(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2012) Ciftci, M. Kemal; Yavuz, Orhan; Hatipoglu, Fatih; Ozdemir, OzgurIn this report, hemorrhagic bowel syndrome (HBS) was defined pathologically for the first time in Turkey in a Holstein dairy cow. It was reported that a 4-year-old cow died suddenly with symptoms of loss of appetite, decreased milk yield, dehydration, and abdominal bloating in a dairy farm. Grossly, serosa of jejunum was observed with dark red color and its lumen was completely filled with blood clots. Some parts of jejunum lumen were narrowed due to submucosal and intramural bleeding. Microscopically, necro-hemorrhagic enteritis, and eosinophilic granulocyte and mononuclear cell infiltrations with extensive submucosal hemorrhages were observed. In addition, Gram-positive, rod-shaped and endospore-forming bacteria were seen intensively around of bleeding areas in the lamina propria. The death was concluded to be associated with HBS by macroscopic and microscopic findings, characteristic for the syndrome and in accordance with the literature evaluating this case. HBS causes significant losses in dairy cattle in many countries of the world. This report aimed to point out the importance of the topic, which is the first case report of HBS in Turkey, where dairy cow enterprises are growing rapidly.Öğe Hybrid Anti Error Propagation Strategies in Noncoherent Cooperative Wireless Networks(IEEE, 2014) Ozdemir, OzgurMaximum likelihood (ML) detection, link adaptive relaying (LAR) and selection relaying (SR) are among the most popular techniques developed for mitigating error propagation in regenerative decode and forward based cooperative wireless networks. In this paper, three different transmission schemes referred to as hybrid LAR and ML (LAR-ML), hybrid SR and ML (SR-ML) and hybrid SR, LAR and ML (SR-LAR-ML) are introduced to combat the error propagation which are obtained by combining the classical ML, LAR and SR approaches. The performance of the proposed structures are determined by computer simulations and providing a general framework for average BER analysis in case of noncoherent binary frequency shift keying which does not require channel state information at either the users or the destination. It has been shown that all of the proposed techniques supply full diversity gain and prevent performance degradation due to error propagation.Öğe Immunohistochemical studies on infectious laryngotracheitis in the respiratory tract lesions in naturally infected laying hens(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2018) Yavuz, Orhan; Ozdemir, Ozgur; Aras, Zeki; Terzi, FundaIn this study, naturally infected by Gallid Herpesvirus type-1 in laying hens to be diagnosed by pathological and PCR methods. Sixty pieces of hens were collected in coops from Central Anatolia region. After necropsy, routine pathological processes were applied to the trachea/larynx, sinuses, lungs and air sacs. All organs were also stained by immunoperoxidase method, and PCR methods were applied to formalin fixed paraffin embedded (FFPE) tissues. Immunohistochemically, the positivities were seen in trachea/larynx (78.3%), sinuses (61.6%), lungs (45%) and air sacs (50%). Positive reactions were observed, in mucous and gland epithelia especially located at intracytoplasmic and rarely intranuclear. PCR positivity was observed in the trachea/larynx in 15 (25%) cases, in infraorbital sinus in 11 (18.3%) cases, in lungs in 8 (13.3%) cases and in air sacs in 6 (10%) cases following the tests performed. Following these results, it is easily concluded that histopathology and immunoperoxidase method can usable for diagnosing of the ILT. However, PCR results made by FFPE tissues showed that this method is not adequate to diagnose the ILT alone.Öğe Joint Network-Channel Coding with Repeat Accumulate Codes for Wireless Relay Networks(IEEE, 2009) Ozdemir, Ozgur; Yilmaz, Ali OzgurThis paper presents two different repetition based joint network channel coding schemes for a three-terminal communication system where two-users want to exchange information via a relay. The transmission is divided into three slots in time where the first and second slots are allocated to the RA (Repeat Accumulate) encoded data of the users. In the first scheme we propose, the relay decodes the received signals and transmits a bit-wise XOR-ed packet using RA coding in the third slot. In the second scheme, the relay demodulates the received signals without decoding and estimates the RA code symbols of each user, then transmits the XOR-ed symbol packet. Unlike the schemes in the literature, the introduced decoding algorithms do not require the relay to decode entire codeword without errors and remove the need for channel feedback without sacrificing the diversity order. The maximum-likelihood decision rule for transmission without channel coding is also derived.Öğe Link Adaptive Relaying with Noncoherent BFSK and DPSK Modulations in Multiple Access Relay Channels(IEEE, 2015) Karabulut, Muhammet Ali; Ozdemir, Ozgur; Ilhan, HaciNetwork coding has recently received significant attention as an innovative approach to improve the throughput of wireless communication systems. The multiple access relay channel (MARC), in which multiple users communicate with a common destination via a relay, is one of the important network coding applications for wireless cooperative communications. In this paper, link adaptive relaying (LAR) approach which combats performance degradation due to error propagation in digital relaying based wireless networks has been applied to the MARC model with noncoherent binary frequency shift keying (BFSK) and differential binary phase shift keying (DPSK) signalings which are among the prominent techniques for eliminating the need for channel estimation by training sequences. Simulation results for Nakagami-m fading channels have shown that the proposed MARC model with LAR scheme outperforms the noncooperative system that involves direct transmissions and overcome the diversity gain reduction due to error propagation.Öğe Link Adaptive Relaying with Virtual Noise Based Detection in Cooperative Wireless Networks(IEEE, 2013) Bozdag, Ahmet; Ilhan, Haci; Ozdemir, OzgurCooperative communication is an approach that provides diversity gain in wireless communications systems by eliminating the requirement of locating physical antenna arrays at terminals. In this study, a scheme that combines link adaptive relaying (LAR) and virtual noise modeling based detection techniques which have been introduced in the literature to prevent performance degradation in decode and forward based cooperative wireless networks due to error propagation is proposed and its error performance is investigated for Nakagami-m channels. It has been shown by simulation results that the proposed system provides significant performance improvement in various situations with respect to the classcial LAR structures in which maximal ratio combining is employed at the destination.Öğe Mitigating Error Propagation in Cooperative Intervehicular Communications(IEEE, 2014) Ozdemir, Ozgur; Ilhan, HaciCooperative wireless communication has attracted intense interest as an alternative way to multiple-antenna systems to obtain spatial diversity. In this paper, we investigate the performance of a vehicle-to-vehicle cooperative scheme where another vehicle in the vicinity of the source vehicle acts as a relay. The underlying source-to-relay, relay-to-destination, and source-to-destination links are modeled as cascaded Nakagami-m fading which provides a realistic description of an intervehicular channel. Unlike the most studies on cooperative intervehicular communications in the literature which are based on analog relaying, we employ digital relaying approach and investigate the performance of the techniques developed for mitigating error propagation in decode and forward based wireless relay systems such as maximum likelihood, cooperative maximal ratio combining, link adaptive relaying, virtual noise based detection and soft information relaying. Simulation results show that detection schemes with these techniques outperform the noncooperative system that involves direct transmission between the source and destination terminals and overcome the diversity gain reduction due to error propagation.
