• Archives of Reconstructive Microsurgery
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• 제11권2호
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• pp.125-134
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• 2002

This study was designed to investigate the process of re- or neo-vascularization in the prefabricated cutaneous flap using a skeletonized arteriovenous pedicle implantation. Fourty-eight flaps were divided into six groups of eight flaps, including control group of the conventional epigastric flap. In experimental groups, skin flap was fabricated by subcutaneous implantation of a distally ligated saphenous arteriovenous pedicle in left abdomen. At 2, 4, 6, 8, and 10 weeks after, prefabricated flap was elevated as an island flap based on implanted pedicle and sutured back in place. Three days after flap repositioning, the area of flap viability was quantified, the pattern of flap vascularization was evaluated with microangiography, and the quantification of vessels was assessed histologically. There were statistically significant differences in flap viability between group 2, 3, 4, and the control (p<0.05), with increased survival area in order. But Group 5 and 6 showed higher flap viability as much as the control did. In the microangiographis study, numerous small meander vessels were newly developed in the vicinity of the implanted pedicle just only 2 weeks after pedicle implantation, but neovascularization around the tip of implanted pedicle, and its anastomosis with native vasculatures was more important for overall flap survival, which was usually developed at least 4 weeks after pedicle implantation. Histologically, vessels are evenly spread over all layers of the flap at 6 weeks after pedicle implantation. The quantification of vessels was correlated well with the improvement of flap viability (p<0.05). In conclusion, neo- and re-vascularization around the tip of implanted pedicle was an important factor for overall survival of the prefabricated flap. Therefore, skeletonized pure vascular pedicle transfer, even though it used alone without surrounding was sufficient to get higher flap viability. The optimal duration of pedicle implantation was8 weeks to obtain maximal survival.

• Journal of Periodontal and Implant Science
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• 제29권2호
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• pp.355-373
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• 1999

Many researches have been reported that collagen as cellular stroma, matrix of grafting materials, mediator of agents for the purpose of promoting healing process invivo, but the responses in vivo were seen various. The goal of this experiment is to assess the effect of collagen on bony healing, through histological evaluation of implanted collagen on the calvarial defect in rats. 2-month-old Sprague-Dawley, 24 rats were used and 12 rats assigned to each group of control and test. Defect of 5mm in diameter was made on the calvarial bone with trephine bur. Following thorough saline rinse, defect of control group was left in empty and that of experimental group was filled with fibrillar collagen($COLLATAPE^{(R)}$, COLLA-TEC. INC. U.S.A.) soaked in saline. 3 rats in each group were sacrificed at 3, 7, 14, 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In the control group, inflammatory responses were disappeared at day 14, but, in the experimental group inflammatory infiltrates were reduced at day 21. Thus, the experimental group showed more severe soft tissue inflammation than control group. 2. Both control and experimental group showed slight appositional growth at day 7 and gradual bony growth to 21th day. But, complete bony healing of the defect was not shown. There was no significant difference in bony healing between control and experimental group 3. Specific response of macrophages for implanted collagen was observed at day 14 in the experimental group. In conclusion, although fibrillar collagen caused inflammation of soft tissue during initial healing period, inflammatory responses by fibrillar collagen didn't inhibit bony regeneration and implanted collagen was biodegradaded by macrophages. Thus, we expect that fibrillar collagen can be used for useful mediator of graft materials or growth factors.

• International Journal of Control, Automation, and Systems
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• 제1권3호
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• pp.368-375
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• 2003

Data fusion approach is investigated to avoid suction in the left ventricular assist system (LVAS) using a nonpulsatile pump. LVAS requires careful control of pump speed to support the heart while preventing suction in the left ventricle and providing proper cardiac output at adequate perfusion pressure to the body. Since the implanted sensors are usually unreliable for long-term use, a sensorless approach is adopted to detect suction. The pump model is developed to provide the load coefficient as a necessary signal to the data fusion system without the implanted sensors. The load coefficient of the pump mimics the pulsatility property of the actual pump flow and provides more comparable information than the pump flow after suction occurs. Four signals are generated from the load coefficient as inputs to the data fusion system for suction detection and a neural fuzzy method is implemented to construct the data fusion system. The data fusion approach has a good ability to classify suction status and it can also be used to design a controller for LVAS.

• 제어로봇시스템학회논문지
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• 제21권7호
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• pp.609-614
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• 2015

Implanted telemetry systems provide the ability to monitor different species of animals while they move within their cages. Species monitored include mice, rats, rabbits, dogs, pigs, primates, sheep, horses, cattle, and others. A miniature transmitter implanted in each animal measures one or more parameters. Parameters measured include arterial pressure, intra-pleural pressure, left ventricular pressure, intra-ocular pressure, bladder pressure, ECG, EMG, EEG, EOG, temperature, activity, and other parameters and transmits the data via radio frequency signals to a nearby receiver. Every conventional dedicated transmitter contains one or more sensors, cpu and battery. Due to the expected life of the battery, the measuring time is limited. To overcome these problems, electromagnetic inductive coupling based wireless power transmission technology using multiple transmit coils were proposed, with each coil having a different active area driven by the coil driver. In this research, a parallel resonance based coil driver and serial resonance based coil driver are proposed. From the experiments we see that the parallel coil driver shows better performance under a low impedance and multiple coils configuration. However, the serial coil driver is more efficient for high impedance transmit coils.

• 방사선산업학회지
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• 제6권4호
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• pp.323-328
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• 2012

In this study, a facile method to fabricate superhydrophobic surfaces on perfluoroalkoxy (PFA) films using ion implantation was developed. PFA films were implanted at 100 keV with a fluence ranging from $4{\times}10^{16}$ to $7{\times}10^{16}ions\;cm^{-2}$. The surface properties of the implanted films were investigated in terms of their surface morphology, wettability, and chemical composition. As the fluence increased to $6{\times}10^{16}ions\;cm^{-2}$, the surface morphology and surface roughness of the PFA films were dramatically changed. The PFA surface implanted at a fluence of $6{\times}10^{16}ions\;cm^{-2}$ showed a maximum contact angle (CA) of $157.1^{\circ}$, while the control CA of the smooth PFA surface was $103.6^{\circ}$. Thus, the superhydrophobic surface was successfully fabricated by ion implantation.

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.927-931
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• 2021

In this work, an attempt is made to improve the electrochemical corrosion resistance of Zircaloy-4 by helium ions implantation. For this purpose, the Zircaloy-4 was implanted with 300 keV helium ions of fluences 1 × 10¹³, 1 × 10¹⁵, and 1 × 10¹⁶ ions-cm^-2 by using Pelletron Accelerator. Electrochemical tests of pristine and ion-implanted samples were performed in NaCl solution and their potentiodynamic polarization curves were obtained. The results showed enhancement of the corrosion resistance of Zircaloy-4 after helium ions implantation. The corrosion rate and current density of the material were significantly reduced by the helium implantation. The decrease in corrosion parameters was attributed to helium ions diffusion inside Zircaloy-4 that reduced the electrons flow from the samples.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1274-1279
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• 2003

Thirty-six Naeimi ram lambs were equally and randomly allotted to four treatment groups with three replications per treatment to determine the simple and additive effects of monensin and zeranol on growth performance, carcass characteristics and nutrient digestibility. The treatment groups were: basal diet-fed lambs (C), monensin-fed lambs (M) where the basal diet was supplemented with 33 mg monensin per kilogram DM, lambs implanted with 12 mg zeranol (Z), and monensin-fed lambs implanted with zeranol (MZ). Lambs fed monensin-containing diet consumed 10.5% less (p<0.05) DM/100 kg weight and were 8.3% more (p<0.05) efficient in converting feed than lambs fed control diet. Zeranol implanted lambs tended to grow 35.2% (p<0.05) faster, consumed 5.1% more (p<0.05) feed and were (p<0.05) 21.9% more efficient in their feed conversion than control lambs. Responses of lambs to monensin and zeranol implants were not additive. Except for Z treatment, there were no marked differences in all carcass characteristics among the various treatment groups. Z-lambs produced 12.7% heavier (p<0.05) carcasses compared with those from C treatment. Also fat parameters, namely, kidney and pelvic fat (KP), body wall thickness and fat thickness, indicated trends for higher finish in Z treatment lambs (p<0.05) than for those lambs from other treatments. Except for CF and ADF, no significant differences in nutrients digestibility were noticed between various treatments; feeding monensin resulted in 24.5% and 8.5% depressions (p<0.05) in CF and ADF digestibility, respectively in comparison to C treatment. Nitrogen retention as percentage of total N-intakes was averaging 7.5 and 20.2% higher (p<0.05) in lambs implanted with zeranol than those fed the M and C diets, respectively.

• Korean Journal of Acupuncture
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• 제20권3호
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• pp.101-114
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• 2003

To study the effects of anti-cancer, anti-metastasis and immune response improvement of herbal-acupuncture with Aucklandiae Radix diffusae herba infusion solution(AKL-HAS), we injected AKL-HAS into Zusanli(St36) of C57BL/6 mice implanted intravenously with B16-F10 melanoma. The results were obtained as follows : 1. In the experiment groups treated with Aucklandiae Radix(AKL) Herbal-Acupuncture, the spleen cell proliferation in Balb/c mouse was significantly increased compared with that of the control group. 2. In the experiment groups treated with Aucklandiae Radix(AKL) Herbal-Acupuncture, the percentage of $CD25^{+}/CD4^{+},\;CD8^{+}/CD3e^{+},\;CD69^{+}/B220^{+},\;NK1.1^{+}/CD3e^{+}$ cells in C57BL/6 mouse PBMCs was increased compared with that of the control group. 3. In the experiment groups treated with Aucklandiae Radix(AKL) Herbal-Acupuncture, the pulmonary colony number of C57BL/6 mice implanted intravenously with B16-F10 melanoma was decreased significantly compared with that of the control group. 4. In the experiment groups treated with Aucklandiae Radix(AKL) Herbal-Acupuncture, MST(Median Survial Time) and ILS(Increase of Life Span) of C57BL/6 mice implanted intravenously with B16-F10 melanoma were increased significantly compared with those of the control group.

• 대한치과보철학회지
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• 제38권3호
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• pp.291-309
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• 2000

Statement of problem. There were several studies on the effects of irradiation to peri-implant bone tissue. However, no clear biological effect of irradiation on peri-implant bone tissue was reported yet. Purpose. This study compared the effect of irradiation on the surrounding tissue of a HA-coated implant fixture with controls. Material and methods. 6 Steri-Oss implants were implanted into the femur of 6 mongrels. The implanted dogs were divided into three groups and received irradiation. After 1 month, 2months and 4 months healing period, the histologic examination and mobility test and digital radiographic imaging analyses were performed to compare the control and experimental group respectively. Results. The irradiated group showed slower healing than control group in light microscopic observations. The mobility test demonstrated significant less number (Periotest) in control group than that of irradiated groups. The digital radiographic imaging analysis showed that the bone density of irradiated group was higher than control group. Conclusion. Generally, control group showed favorable biological response and less mobility than irradiated group. The conflict result of bone density value were measured by the digital radiographic imaging analysis. The digital radiographic imaging analysis needs more research in future.

• Transactions on Control, Automation and Systems Engineering
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• 제1권1호
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• pp.32-43
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• 1999

Adaptive robust control scheme is introduced for flexible joint manipulator with nonlinearities and uncertainties. The system does not satisfy the matching condition due to insufficient actuators for each node. The control only relies on the assumption that the bound of uncertainty exists. Thus, the bounded value does not need to be known a prior. The control utilizes the update law by estimating the bound of the uncertainties. The control scheme uses the backstepping method and constructs a state transformation. Also, stability analysis is done for both transformed system and original system.