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Background: Although some studies have reported significant reductions in food cravings following the single-session of repetitive transcranial magnetic stimulation (rTMS), there is little research on the effects of multi-session of rTMS on food consumption and body weight in obese subjects. Objective: We conducted 4-week randomized, sham-controlled, single-blind, parallel-group trial to examine the effect of rTMS on body weight in obese adults. Methods: Forty-three obese patients (body mass index [BMI] ≥25 kg/m2) aged between 18 and 70 years were randomized to the sham or real treatment group (21 in the TMS group and 22 in the sham treatment group). A total of 8 sessions of rTMS targeting the left dorsolateral prefrontal cortex (DLPFC) was provided over a period of 4 weeks. The primary outcome measure was weight change in kilograms from baseline to 4 weeks. Secondary endpoints included changes in anthropometric measures, cardiovascular risk factors, food intake, and appetite. Results: Participants in the rTMS group showed significantly greater weight loss from baseline following the 8 session of rTMS (−2.75 ± 2.37 kg vs. 0.38 ± 1.0 kg, p

Asphaltenes, precipitated from oil due to pressure, temperature, or oil compositional changes, can affect not only the performance of CO2 enhanced oil recovery (EOR), but also carbon capture and storage (CCS) by reducing porosity and permeability and altering wettability. A comprehensive solid deposition model, which includes adsorption, pore throat plugging, and re-entrainment, was developed to predict the amount of precipitated asphaltene under dynamic conditions. In this study, a hysteretic three-phase fluid flow model was used to simulate residual and solubility trapping during the water alternating gas (WAG) process. Alteration of rock wettability during asphaltene deposition led to a decrease in oil and gas mobility and an increase in water mobility, increasing the amount of CO2 residual trapping to 39%, via a hysteresis effect. Residual trapped CO2 replaced liquids in the pore space; more water was substituted when asphaltene deposition was considered than that without it because of greater water mobility. Consequentially solubility and residual trapping were overestimated by 20% and underestimated by 39% when asphaltene deposition was not considered. Formation damage by asphaltene deposition increased water production by 14% and decreased oil recovery by 9% compared to a model without asphaltene deposition. These results indicate that asphaltene deposition affects CO2 trapping mechanisms and EOR performance during coupled CO2 EOR and storage processes.

Growing evidences show that gut microbiota is associated with the pathogenesis of Parkinson's disease (PD) and the gut-brain axis can be promising target for the development of the therapeutic strategies for PD. Acupuncture has been used to improve brain functions and inflammation in neurological disorders such as PD, and to recover the gastrointestinal dysfunctions in various gastrointestinal disorders. Thus, we investigated whether acupuncture could improve Parkinsonism and gut microbial dysbiosis induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. First, we observed that acupuncture treatment at acupoints GB34 and ST36 could improve motor functions and comorbid anxiety in PD mice. Next, we found that acupuncture increased the levels of dopaminergic fibers and neurons in the striatum and the substantia nigra, respectively. Acupuncture also restored the overexpression of microglia and astrocyte as well as conversion of Bax and Bcl-2 expression in both the striatum and the substantia nigra, indicating that inflammatory responses and apoptosis were blocked by acupuncture. Additionally, via 16S rRNA sequence analysis, we observed that the relative abundance of 18 genera were changed in acupuncture-treated mice compared to the PD mice. Of them, Butyricimonas, Holdemania, Frisingicoccus, Gracilibacter, Phocea, and Aestuariispira showed significant correlations with anxiety as well as motor functions. Furthermore, the predicted functional analyses showed that acupuncture restored the physiology functions such as glutathione metabolism, methane metabolism, and PD pathway. In conclusion, we suggest that the effects of acupuncture on the enhanced motor function and the protection of the dopaminergic neurons may be associated with the regulation of the gut microbial dysbiosis and thus the inhibition of the neuroinflammation in the PD mice.

Background: Although some studies have reported significant reductions in food cravings following repetitive transcranial magnetic stimulation (rTMS), none have examined changes in body weight. Objective: We conducted 2-week randomized, sham-controlled, single-blind, parallel-group trial to examine the effect of rTMS on body weight in obese patients. Methods: Sixty obese patients (body mass index [BMI] ≥25 kg/m2) aged between 18 and 65 years were recruited. A total of 4 sessions of rTMS targeting the left dorsolateral prefrontal cortex (DLPFC) was provided over a period of 2 weeks, with a follow-up assessment conducted two weeks after treatment had finished. The primary outcome measure was weight change in kilograms from baseline to 4 weeks. Secondary endpoints included changes in anthropometric measures, cardiovascular risk factors, food intake, and appetite. Results: Of the 60 volunteers, 57 completed the 4-week follow-up (29 in the TMS group and 28 in the sham treatment group). Participants in the rTMS group showed significantly greater weight loss from baseline following the 4 session of rTMS (p = 0.002). Consistent with weight loss, there was a significant reduction in BMI, fat mass and VAT at week 4 in the rTMS group compared with the control group (p

Although gallium-based liquid metals are attracting growing interest thanks to its potential applications in deformable, flexible electronic devices, challenges in fabrication associated with the high surface tension and oxide skin remain to be overcome. We report a novel fabrication technique for liquid metal circuits using dewetting. An excessively thin liquid film spontaneously shrinks on a substrate to reduce surface free energy. In the case of a thin liquid metal film on a substrate with microgrooves, the oxide on the microgroove wall and the additional viscous resistance delay the shrinkage in the grooves, which separates the liquid volume inside the microgrooves from the external volume. Utilizing this mechanism, we successfully produced 20- $\mu \text{m}$ -thick conductive lines of eutectic gallium indium (EGaIn) on polydimethylsiloxane. This fabrication technique is simple, fast, and cost-effective and requires no top covering layer. The resultant metal lines show potentially applicable electrical resistance to flexible and stretchable electronic devices. [2017-0082]

Researches on Ultra High Performance Concrete (UHPC) have been conducted worldwide owing to its outstanding durability and strength performances compared to those of normal concrete. The application of UHPC to prestressed concrete structures, which may seem to be the most appropriate and beneficial, may result significant improvement in the design of anchorage zones due to its high compressive and tensile strength. The size of anchorage blocks and amounts of reinforcements may be reduced drastically. This paper examines the stress magnitudes and distributions of post-tensioned anchorage zones using UHPC which have nominal compressive strength levels of 120, 150 and 180 MPa respectively, by FE analysis. The analytic results are verified with the existing experimental work of 180MPa UHPC. It can be concluded that the use of UHPC to post-tensioned members gives significant reduction of anchorage zone size and no reinforcements are required.

Although research on CO2 injection in shale gas reservoirs has been focused for enhanced gas recovery (EGR) and CO2 storage, previous studies have not examined both multi-component transport and geomechanical effects. Therefore, this study presents new shale gas models for CO2 injection considering multi-component adsorption, dissolution, molecular diffusion, and stress-dependent compaction. Based on these mechanisms and data for Barnett shale field, a simulation model was constructed for CO2 flooding and huff and puff. The proposed model was used to examine the effects of CO2 injection to EGR and CO2 storage and various mechanisms. The results presented that CO2 flooding and huff and puff improve CH4 production by 24% and 6% respectively compared with no injection scenario. At the end of simulated time, the injected CO2 is stored as free, adsorbed, and dissolved states in proportions of 42%, 55%, and 3% respectively. To confirm these results, Marcellus and New Albany shale models, which have different reservoir properties, are generated and compared with Barnett shale model. However, in Marcellus and New Albany shale models, effects of CO2 injection are lower than that of Barnett shale model. Therefore, to investigate factors affecting to the efficiency of CO2 injection in shale gas reservoirs, extensive simulations were performed. Results of the simulation analyses show that natural fracture permeability, hydraulic fracture half-length, well spacing, and Langmuir constants are significant factors for EGR and CO2 storage. For the real applications, these parameters should be mainly considered. The investigations performed in this study present better understanding of CO2 injection processes to EGR and CO2 storage and they are important for optimizing the designs of CO2 injection in field applications.

멀티미디어 기술은 최근 몇 년 동안 상당한 발전이 있었다인터넷을 통해 오디오동영상이미지와 같은 멀티미디어를 전송하는 것이 이제 아주 보편화 되었다그러나 인터넷은 안전하지 못한 채널로 보안적인 측면에서 많은 문제들을 가지고 있다또한 데이터 복제를 할 수 있는 기기가 보편화 된 이후 멀티미디어 콘텐츠 이용자의 저작권에 대한 인식부족으로 인해 멀티미디어 콘텐츠의 불법복제 문제는 날이 갈수록 심각해지고 있다인터넷과 같은 비보안 채널 상에서 멀티미디어 데이터의 안전성과 기밀성을 획득하기 위해 많은 암호기술이 제안되어왔다특히 영상을 암호화하기 위한 가장 간단한 방법은 의사 난수열을 이용하여 기저영상을 만든 후 기저영상과 원 영상의 픽셀값을 연산을 취해 원 영상의 픽셀값을 변화시키는 것이다이러한 방법으로 영상을 암호화하는 경우하드웨어의 구현이 용이하고 암호화 속도가 빠른 장점이 있다 셀룰라 오토마타 이하 란 이산 시간의 동적 시스템으로 셀이라는 기본 단위 메모리의 배열로 이루어진다이 시스템에서 셀의 다음 상태는 자기 자신과 인접한 두 셀의 상태에 의해 정해진 규칙에 의해 갱신된다이러한 는 간단하고규칙적이며작은 단위로 확장 연결할 수 있는 구조이기 때문에 하드웨어 구현에 알맞다 가장 간단한 구조를 가지는 차원 는 모든 셀이 선형으로 배열되어 있고 의 상태전이에 적용되는 규칙의 종류에 따라 선형 와 비선형 로 나뉜다또한 의 모든 상태에 대하여 이전상태가 존재하는 를 그룹 라 하고 그룹 는 셀들이 일

Primary extradural meningioma is about 1-2% of all meningiomas. Primary intraosseous meningioma is a rare form of intra-bone tumors that account for approximately 67% of extradural meningiomas. We report a primary intraosseous meningioma of a 69-year-old man who had headaches and a mass on right parietal scalp for the past few months. Remarkably, the brain tissue within the osteolytic cavity of the skull was normal in computed tomography and magnetic resonance images. Resection, duraplasty, and cranioplasty were performed. The patient's symptoms disappeared after surgery, and the histological diagnosis was an osseous meningothelial meningioma (World Health Organization grade I).

A 2-axis gimbal-type X-band antenna has been widely used to effectively transmit the high reso-lution image data from the observation satellite to the desired ground station. However, a dis-continuous stepper motor activation for rotating the pointing mechanism in azimuth and elevation di-rections induces undesirable micro-vibration disturbances which can result in the image quality degra-dation of a high-resolution observation satellite. To enhance the image quality of the observation sat-ellite, attenuating the micro-vibration induced by an activation of the stepper motor for rotational movements of the antenna is important task. In this study, we proposed a low-rotational-stiffness blade gear applied to the output shaft of the stepper motor to obtain the micro-vibration isolation performance. The design of the blade gear was performed through the structure analysis such that this gear is satisfied with the margin of safety rule under the derived torque budget. In addition, the micro-vibration isolation performance of the blade gear was verified through the micro-vibration measurement test using the dedicated micro-vibration measurement device proposed in this study.

The Non-Destructive Test techniques on concrete, which can assess the properties of materials without damages, have been developed as the deteriorations of existing structures increase. Among them, the ultrasonic pulse velocity (USPV) method is widely used because it can investigate the states of one material for a long time and repeatedly. However, there have been few researches on the NDT application to geopolymer concrete which is environment friendly construction material without any cement. This paper investigates the variations of ultrasonic pulse velocity and peak frequency of geopolymer concrete under monotonically increasing loads to assess the material conditions with various compressive strength levels by measuring P-wave signals. The pulse velocities and peak frequencies were higher in high strength geopolymer concrete specimens. There are not explicit relations between strength levels and peak frequencies but the peak frequencies are strongly influenced by the applied stress levels. In addition, a predicting equation for compressive strength of geopolymer concrete is derived based on experimental data in similar form for normal concrete.

Atopic dermatitis (AD) syndrome is one of the most common and severe skin diseases in Korea; a large populationhas this disease. We examined the effects of the extract from the leaf and sprig of Camellia sinensis on the developmentof AD by using NC mice as a model of atopic dermatitis. Oral administration of the extract to NC/Nga micetreated with 2,4-dinitrochlorobenzene (DNCB) inhibited the development of AD-like skin lesions as shown by a significantdecrease in the skin symptoms of the disease and a decrease in ear thickness and levels of immunoglobulinE (IgE) and thymus-and activation-regulated chemokine (TARC) level in the skin. Administration of the extract markedlysuppressed the DNCB-induced mRNA expression of interleukin 4 (IL-4) and tumor necrosis factor α (TNF α). The findings suggest that transdermal application of the extract may modulate in the skin of NC/Nga mice. The extractwas effective for the prevention and treatment of AD.

Aneurysms arising from non-branching sites of the supraclinoid internal carotid artery (ICA) are considered rare, accounting for only 0.9-6.5% of all ICA aneurysms. They are thin-walled, broad-based, can easily rupture during surgery, and are referred to as dorsal, superior, anterior, or ventral wall ICA aneurysms, as well as blister-like aneurysms. Various treatment modalities are available for blister-like aneurysms, but with varying success. Here, we report on two cases of saccular shaped dorsal wall aneurysms. Both patients were transferred to the emergency department with subarachnoid hemorrhage because of an aneurysmal rupture. Computed tomography angiography and transfemoral cerebral angiography (TFCA) showed a dorsal wall aneurysm in the distal ICA. We performed clipping on the wrapping material (Lyodura®, temporal fascia). Follow-up TFCA showed rapid configuration changes of the right distal ICA. Coil embolization was also performed as a booster treatment to prevent aneurysm regrowth. Both patients were discharged without neurologic deficit. No evidence of aneurysm regrowth was observed on follow-up TFCA at two years. Dorsal wall ICA aneurysms can change in size over a short period; therefore, follow-up angiography should be performed within the short-term. In cases of regrowth, coil embolization should be considered as a booster treatment.

In this paper, the specific absorption (SA) distribution in a human body, exposed to ultra-wideband (UWB) pulse, has been analyzed by taking into account the dispersion characteristics of biological tissues. The dispersive properties of biological tissues are characterized by the 4-pole Cole-Cole model. However, implementing the finite-difference time-domain (FDTD) method of the 4-pole Cole-Cole model requires many resources and the calculation time. The complicated dispersive characteristics of biological tissues create difficulties in the analysis of exposure assessment by on-body devices. Because UWB frequency band is from 3.1 to 10.6 GHz, the dispersive characteristic may be sufficient to the 1-pole Cole-Cole model. In this paper, we fitted the 4-pole Cole-Cole model by the 1-pole Cole-Cole model for the given UWB band. The fitted results are in good agreement with the 4-pole Cole-Cole model. The FDTD method with the dispersive algorithm for the 1-pole Cole-Cole model was applied using SA analysis of ...

Well testing in unconventional reservoirs, such as tight or shale gas formations, presents considerable challenges. It is difficult to estimate the reservoir properties in ultra-low permeability formation because of poor inflow prior to stimulation and excessive test duration. Moreover, radial flow may not develop in hydraulically fractured horizontal wells. For these reasons, the cost of test is high and the accuracy is relatively low. Accordingly, industry is turning to an alternate testing method, diagnostic fracture injection test (DFIT), which is conducted prior to the main hydraulic fracture treatments. Nowadays, DFIT are regarded as the most practical way to obtain good estimates of reservoir properties in unconventional reservoirs. Various methods may be used for interpreting DFIT data. This paper gives an explanation of those methods in detail and examines three actual field data. These show how various analysis methods can be applied to consistently interpret fracture closure pressure and time, as well as before and after closure flow regimes and reservoir properties from field data.

Although the motion of the three-phase contact line on a solid substrate has been extensively studied thus far, the understanding of the dynamics of the contact line of liquid/liquid/gas phases is far from complete. Here we deposit a drop of isopropyl alcohol (IPA) on water and HFE-7100 whose free surfaces are exposed to air to observe the flow field around the contact line. By combining the shadowgraph and high-speed imaging techniques, we find that vortices are spontaneously generated at the contact line, which grow in size with time. The flow is attributed to the Marangoni stress that pulls a liquid of lower-surface tension toward a liquid surface having a higher surface tension. However, it is not still clear why the entrained lower-surface-tension liquid should whirl rapidly beneath the contact line. We also visualize the flow by the particle image velocimetry (PIV) to find out that the rotational velocity reaches the order of 1 mm/s near the free surface.

Objective : To evaluate the surgical efficacy of and factors associated with decompressive craniectomy in patients with an internal carotid artery (ICA) territory infarction. Methods : Seventeen patients (8 men and 9 women, average age 61.53 years, range 53-77 years) were treated by decompressive craniectomy for an ICA territory infarction at our institute. We retrospectively reviewed medical records, radiological findings, and National Institutes of Health Stroke Scale (NIHSS) at presentation and before surgery. Clinical outcomes were assessed using the Glasgow Outcome Scale (GOS). Results : Of the 17 patients, 15 (88.24%) achieved a poor outcome (Group A, GOS 1-3) and 2 (11.76%) a good outcome (Group B, GOS 4-5). The mortality rate at one month after surgery was 52.9%. Average preoperative NIHSS was 27.6±10.88% in group A and 10±4.24% in group B. Mean cerebral infarction fraction at the septum pellucidum level before surgery in group A and B were 33.67% and 23.72%, respectively. Mean preoperative NIHSS (p=0.019) and cerebral infarction fraction at the septum pellucidum level (p=0.017) were found to be significantly associated with a better outcome. However, no preexisting prognostic factor was found to be of statistical significance. Conclusion : The rate of mortality after ICA territory infarction treatment is relatively high, despite positive evidence for surgical decompression, and most survivors experience severe disabilities. Our findings caution that careful consideration of prognostic factors is required when considering sur gical treatment.

In this paper, we studied the propagation of the radio wave in the human body for WBAN system and proposed the path-loss models applicable in the MICS and ISM frequency band. Human Tissues are composed of complicate organ. So it is difficult to measure to insert the probe in human body. Accordingly, the equations were modelled by electromagnetic analysis using the numerical phantom based on the real human. The numerical analysis used XFDTD 6.5 of Remcom co. in commercial software based on the Finite-Difference Time-Domain method. Human body model used a standard adult Korean model developed by ETRI. The proposed channel models will be very helpful to design the WBAN system.

°First and Corresponding Author:Electronics and Telecommunications Research Institute, kyg63491@etri.re.kr, 정회원* Electronics and Telecommunications Research Institute, thkim@etri.re.kr, 정회원**Kunsan National University Department of Information and Telecommunication Engineering, sskang@kunsan.ac.kr, 정회원논문번호：KICS2014-08-320, Received August 25, 2014; Revised September 17, 2014; Accepted September 17, 2014

This paper presents a tumor detection system for breast cancer that utilizes two-dimensional (2D) image reconstruction with microwave tomographic imaging. The breast cancer detection system under development consists of 16 transmit/receive antennas, and the microwave tomography system operates at 900 MHz. To solve a 2D inverse scattering problem, the method of moments (MoM) is employed for forward problem solving, and the simplex method employed as an optimization algorithm. The results of the reconstructed image show that the method accurately shows the position of a breast tumor.

The use of high frequency band, broad band and MIMO antenna is expected in the next generation mobile communication system. By the rapid increase of demand for wireless communications and the explosive increase of the mobile communication services, researches for optimization of next-generation mobile communication system are required. In the existing MIMO channel models, propagation-environments are commonly classified into urban, suburban, rural area, etc. However such approaches can have drawbacks in that many different morphologies may exist even in the urban area, for example. In this paper, we introduced path morphology concept, and proposed the method of morphology classification considering the building height, density, etc. Delay spread(DS), angular spread(AS) of AoD and AoA analyzed for each environment using the ray tracing technique. Based on the analysis, a MIMO channel model appropriate in domestic environment was suggested.

Objectives: The aim of the present study was to investigate the efficacy of synthetic suburethral slings in female stress urinary incontinence (SUI) patients with overactive bladder (OAB). Methods: From May 2002 to April 2005, a total of 295 women with SUI underwent suburethral sling procedure. Of the 295 women, only those who were followed up for at least 12 months were included in the study, yielding 236 patients. The patients were divided into three groups: pure SUI; SUI with OAB dry; and SUI with OAB wet. Telephone questionnaires by were used to evaluate the postoperative improvement of SUI and storage symptoms. Results: There were significant differences in preoperative symptom score, quality of life (QoL) score, and preoperative voided volume among the three groups. There were no significant differences among the three groups in terms of the cure rate for the stress component (group 1, 88.6%; group 2, 86.2%; group 3, 86.7%; P = 0.943). Eighty percent of group 1 patients improved in frequency, but two patients (2.3%) complained of de novo urgency. In group 2, 81.5 and 82.7% improved in frequency and urgency, respectively, but one patient (1.7%) complained of de novo urge incontinence. In group 3, 76.9 and 84.4% improved in frequency and urge incontinence, respectively. Conclusion: Suburethral slings are simple, safe and highly effective in treating SUI with OAB.

In the domestic environments, there are many tunnels since most of terrains have mountains. To ensure the quality of wireless network service in NLOS environment like tunnels which differ from indoor or outdoor wireless channels, researches on wave-propagation characteristics. through such channel are necessary. Especially, in such environment the ground repeater called Gap-Fillers are usually used for satellite mobile services. To make sure that mobile service using satellites in tunnels is available, the research about Gap Filling method is essential. This research is focus on the characterising the wave-propagation through tunnels, to find the appropriate frequency, HPBW of the Gap-Filler antennas, the number of Gap-Fillers, etc. In this paper, we present the effective Gap Filling method in tunnels for ISM band, based on analysis of ray tracing and measurement results.

This paper proposes an electronically beam steering array antenna, consisting of single fed active element and 4 parasitic elements, operating in 5.8 GHz ISM band. Beam steering can be achieved by controlling the reactance of the variable reactance control circuit connected to the load of the parasitic elements without using the high cost phase shifters. The proposed antenna realizes beam scanning of E-plane and H-plane with the below -10 dB return loss in ISM band. The gain of the in E-plane and in H-plane is shown in the scanning range.

A novel electromagnetic band gap (EBG) synthesis method for mixed signal applications is presented. In this method, a genetic algorithm (GA) is utilized as a solution-searching technique. One of the main advantages of the proposed method is an automated design procedure for EBG structures that meet given design specifications. For this purpose, the GA method is combined with multilayer finite-difference method (M-FDM) and dispersion diagram (DD) method. The M-FDM is a circuit-based simulator for computing the Z-parameters of planar structures, while the DD method is a plot of the propagation constant versus frequency. The EBG synthesis method introduced in this paper consists of three main parts namely: 1) GA, which generates populations of EBG structures and evaluates fitness functions using band gap response results from DD; 2) M-FDM, which analyzes the EBG structures generated by the GA and links the analysis results to DD; 3) DD, which calculates band gap frequencies using the EBG structure analysis results from the M-FDM and links the calculated stop band frequencies to the GA for fitness checks. For the verification of the suggested method, EBG structures having various specifications have been designed using the EBG synthesizer tool described in this paper. The designed EBG structures have been modeled and simulated using M-FDM. The EBG structures have also been fabricated and measured in the frequency-domain. The corresponding frequency-domain simulations and measurements have exhibited band gaps as per the design specifications used to synthesize the EBG structures.

We demonstrated that manganese (Mn)-doped GaN nanowires (NWs) exhibit p-type characteristics using current–voltage (I–V) characteristics in both heterojunction p–n structures (GaN:Mn NWs/n-Si substrate) and p–p structures (GaN:Mn NWs/p-Si). The heterojunction p–n diodes were formed by the coupling of the Mn-doped GaN NWs with an n-Si substrate by means of an alternating current (AC) dielectrophoresis-assisted assembly deposition technique. The GaN:Mn NWs/n-Si diode showed a clear current-rectifying behavior with a forward voltage drop of 2.4 V to 2.8 V, an ideality factor of 30 to 37, and a parasitic resistance in the range of 93 kΩ to 130 kΩ. On the other hand, we observed that other heterojunction structures (GaN:Mn NWs/p-Si) showed no rectifying behaviors as seen in p–p junction structures.

We have investigated the size-effect of the nano-Schottky diodes on the electrical transport properties and the temperature-dependent current transport mechanism in a metal-semiconductor nanowire junction (a Ti/GaN nano-Schottky diode) using current-voltage characterization in the range of 300-423 K. We found that the modified mean Schottky barrier height (SBH) was approximately 0.7 eV with a standard deviation of approximately 0.14 V using a Gaussian distribution model of the barrier heights. The slightly high value of the modified mean SBH (approximately 0.11 eV) compared to the results from the thin-film based Ti/GaN Schottky diodes could be due to an additional oxide layer at the interface between the Ti and GaN nanowires. Moreover, we found that the abnormal behavior of the barrier heights and the ideality factors in a Ti/GaN nano-Schottky diode at a temperature below 423 K could be explained by a combination of the enhancement of the tunneling current and a model with a Gaussian distribution of the barrier heights.

We report on the multiple ZnO nanowires field-effect transistors (FETs), which were formed by assembling as-synthesized ZnO nanowires on a SiO2/Si substrate using an optimized alternating current (AC) dielectrophoresis (DEP) technique in three-probe back-gate geometry. The AC DEP was optimized with a bias voltage of 10 Vp-p at a frequency of 10 kHz. Our multiple ZnO nanowires FETs containing ca. 50∼65 nanowires in one device exhibited excellent electrical characteristics with a transconductance of 3∼11.5 μS at a drain voltage of 1∼5 V, a mobility of ∼30 cm2/V·s, and a carrier concentration of 9.4 × 1017 cm-3. For a comparison study, we also present conventional single ZnO nanowire FETs prepared by e-beam lithography with a back-gate structure.

The fabrication of low-loss transmission line structures with an air dielectric layer is described. The channels are characterized at low frequency (10 and 100 kHz) using capacitance and loss tangent and at high frequency (500 MHz to 10 GHz) using -parameter measurements. The incorporation of an air gap resulted in structures with effective dielectric constants between 1.5-1.8 and significantly lower loss tangents. The fabrication technique could be used to create more complicated air gap transmission line structures for use in monolithic microwave integrated circuits.

We report on investigation of the AC dielectrophoresis aligned assembly deposition (DAAD) of gallium nitride nanowires (GaN NWs) with both the variation of the electric field and the frequency. Our DAAD methods were used to align and manipulate GaN nanowires as well as to extract the electrical properties of semiconducting nanowires. We observed that the ability of the alignment strongly depends on the magnitude of the AC electric field and frequencies. For the higher AC peak-to-peak electric fields (up to 20 Vp-p), the GaN nanowires have a better alignment across the patterned Ti / Au electrodes with a high yield rate of ~ 90% over the entire arrays (in our case, 20 arrays) in the chip at the 20 kHz. From the transport measurements of our AC aligned GaN nanowires using conventional three-probe schemes in field-effect transistor structures, we found that the conductance of the GaN NWs increased for gating voltage greater than zero and decreased for gating voltage less than zero, indicating these GaN nanowires have n-type dopants.

This is a report on the electrical characterization of gallium nitride (GaN) nanowire (NW) p–n junction diodes. These diodes were formed by assembling n-GaN NWs on p-Si (1 0 0) substrates using alternating current (AC) dielectrophoresis (DEP). The AC DEP was optimized with a bias voltage of 15 V p−p at a frequency of 1 kHz. The hetero-junction single GaN nanowire p-n diode (n-GaN NW/p-Si) showed well-defined current rectifying behavior with a forward voltage drop of 1.2–2.0 V at a current density of 10–60 A/cm 2 . The GaN nanowire p–n diodes had a high parasite resistance in the range of >470 kΩ. We observed that these high resistances were mostly the result of the metal contacts to the n-GaN NWs. We also found that these parasite resistances were reduced by the formation of an additional capping layer on the top of the n-GaN NW as well as high temperature annealing.

We demonstrate the fabrication and the electrical transport properties of single crystalline 3C silicon carbide nanowires (SiC NWs). The growth of SiC NWs was carried out in a chemical vapor deposition (CVD) furnace. Methyltrichlorosilane (MTS, CH3SiCl3) was chosen as a source precursor. SiC NWs had diameters of less than 100 nm and lengths of several μm. For electrical transport measurements, as-gown SiC NWs were prepared on a highly doped silicon wafer, pre-patterned by a photo-lithography process, with a 400 nm thick SiO2 layer. Source and drain electrodes were defined by e-beam lithography (EBL). Prior to the metal deposition (Ti/Au : 40 nm/70 nm) by thermal evaporation, the native oxide on SiC NWs was removed by buffered HF. The estimated mobility of carriers is 15 cm2/(Vs) for a source-drain voltage (VSD) of 0.02 V. It is very low compared to that expected in bulk and/or thin film 3C-SiC. The electrical measurements from nanowire-based field effect transistor (FET) structures illustrate that SiC NWs are weak n-type semiconductor. We have also demonstrated a powerful technique, a standard UV photo-lithography process, for fabrication of SiC nanowires instead of using EBL process.

We report on a simple and effective ac and dc dielectrophoresis (DEP) method that can be used to align and manipulate semiconductor gallium nitride (GaN) nanowires (NWs) with variations in the type of electrical fields as well as variations of frequency. We observed that the ability of the alignment and the formation of the assembling nanowires (single or a bundle configuration) strongly depend on the magnitude of both the ac and dc electric fields. The yield results indicate that the GaN NWs, using ac DEP, are better aligned with a higher yield rate of approximately 80% over the entire array in the chip than by using dc DEP. In addition, we first demonstrated the simple hybrid p-n junction structures assembled by n-type GaN nanowires together with a p-type silicon substrate (n-GaN NW/p-Si substrate) using dielectrophoresis. From the transport measurements, the p-n junction structures show well-defined current rectifying behaviour with a low reverse leakage current of approximately 3 x 10(-4) A at -25 V. We believe that our unique p-n junction structures can be useful for electronic and optoelectronic nanodevices such as rectifiers and UV nano-LEDs.

Percutaneous vertebroplasty (PVP) is an effective treatment for lesions of the vertebral body that involves a percutaneous injection of polymethylmethacrylate (PMMA). Although PVP is considered to be minimally invasive, complications can occur during the procedure. We encountered a renal embolism of PMMA in a 57-year-old man that occurred during PVP. This rare case of PMMA leakage occurred outside of the anterior cortical fracture site of the L1 vertebral body, and multiple tubular bone cements migrated to the course of the renal vessels via the valveless collateral venous network surrounding the L1 body. Although the authors could not explain the exact cause of the renal cement embolism, we believe that physicians should be aware of the fracture pattern, anatomy of the vertebral venous system, and careful fluoroscopic monitoring to minimize the risks during the PVP.

In this article, we designed the broadband square loop antenna with a parasitic loop. To increase bandwidth of the single square loop antenna, we desinged the antenna with the parasitic loop at outside of the square loop. The feeding method of the proposed antenna is fed by a coplanar waveguide structure. We analyzed and designed the antenna by using Ansoft co.' HFSS. The bandwidth of the proposed antenna with the parasitic loop was increased above 2.5 times compared with single square loop antenna. The proposed antenna has an impedance bandwidth of 2.52 GHz under the condition below voltage standing wave ratio two and a maximum gain of 8.7 dBi at the operating frequency of 6.4 GHz. The designed antenna could be used to support WLAN communications and ITS applications bands. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2302–2304, 2013

Electric field assisted assembly of single walled carbon nanotubes (SWCNTs) on lithographically patterned electrodes has been studied using both dc and ac electric fields. The nanotube alignment is strongly dependent on the magnitude and the frequency of the applied electric field. An improved carbon nanotube (CNT) orientation is achieved with ac electric field of high frequency due to alternating force exerted rapidly on field-induced dipoles of the nanotubes and the nanotubes orient nearly at right angle to the metal electrodes. The purification of as-prepared CNTs from background nanoparticles appears possible by aligning nanotubes with an ac electric field.

The bubble oscillations play an important role in ultrasonic cleaning processes. In the ultrasonic cleaning of semiconductor wafers, the cleaning process often damages micro/nano scale patterns while removing contaminant particles. However, the understanding of how patterns in semiconductor wafers are damaged during ultrasonic cleaning is far from complete yet. Here, we report the observations of the motion of bubbles that induce solid wall damage under 26 kHz continuous ultrasonic waves. We classified the motions into the four types, i.e. volume motion, shape motion, splitting or jetting motion and chaotic motion. Our experimental results show that bubble oscillations get unstable and nonlinear as the ultrasonic amplitude increases, which may exert a large stress on a solid surface raising the possibility of damaging microstructures.

Electromagnetic bandgap (EBG) structures that provide an excellent isolation within the stopband are extremely effective in suppressing propagation of simultaneous switching noise on parallel power planes. However, a scattering parameter measurement and full-wave electromagnetic simulation for their entire structure are costly and time consuming. This letter presents a two-dimensional dispersion-diagram analysis based on a unit-cell network of EBG structures by extending a well-known dispersion-diagram analysis of one-dimensional infinite periodic structures. The approach is extremely effective in computing stopband frequencies and provides the stopbands with good agreement to the measured results

The space borne X-band 2-axis gimbal antenna needs frequency re-uses techniques by dual circular polarization for the very high data transmission. The gimbal antenna consists of 2-axis driving mechanism, high efficient horn antenna, very low loss non-contact type RF transmission line of coaxial type rotary joint. This paper designed high efficient horn antenna and very low loss non-contact type RF transmission line of coaxial type rotary joint and 2-axis driving mechanism.

This paper describes the W-band fully polarimetric radiometer design and the measurement results of material's emissivity of rubber sheet and water as examples using developed radiometer. The measured brightness temperatures of sample materials depend on incident angle. For this angle dependent measurement, the test set-up was designed. Using the measured brightness temperature, the characteristics of material like emissivity and dielectric constant can be retrieved. Finally, the comparison between theoretical value and measurement value are also listed in the paper.

Spontaneous cervical epidural hematoma (SCEDH) is a rare disease, but can cause severe neurologic impairment. We report a case of a 68-year-old female who presented with sudden onset, posterior neck pain, right shoulder pain, and progressive right hemiparesis mimicking stroke with no trauma history. Initial brain CT and diffusion MRI performed to rule out brain lesion did not show any positive findings. Laboratory examination presented only severe thrombocytopenia (45,000/mm(3)). Subsequent cervical MRI revealed a cervical epidural mass lesion. We confirmed that it was pure hematoma through C5 unilateral total laminectomy and C6 partial hemilaminectomy. She achieved complete neurologic recovery with active rehabilitation. Early surgical decompression for SCEDH with neurologic impairment should be recommended for better outcome.

Objective : In the present study, authors retrospectively reviewed the clinical outcomes of halo-vest immobilization (HVI) versus surgical fixation in patients with odontoid fracture after either non-surgical treatment (HVI) or with surgical fixation. Methods : From April 1997 to December 2008, we treated a total of 60 patients with upper cervical spine injuries. This study included 31 (51.7%) patients (22 men, 9 women; mean age, 39.3 years) with types II and III odontoid process fractures. The average follow-up was 25.1 months. We reviewed digital radiographs and analyzed images according to type of injury and treatment outcomes, following conservative treatment with HVI and surgical management with screw fixation. Results : There were a total of 31 cases of types II and III odontoid process fractures (21 odontoid type II fractures, 10 type III fractures). Fifteen patients underwent HVI (10 type II fractures, 5 type III fractures). Nine (60%) out of 15 patients who underwent HVI experienced successful healing of odontoid fractures. The mean period for bone healing was 20.2 weeks. Sixteen patients underwent surgery including anterior screw fixation (6 cas es), posterior C1-2 screw fixation (8), and transarticular screw fixation (2) for healing the odontoid fractures (11 type II fractures, 5 type III fractures). Fifteen (93.8%) out of 16 patients who underwent surgery achieved healing of cervical fractures. The average bone healing time was 17.6 weeks. Conclusion : The overall healing rate was 60% after HVI and 93.8% with surgical management. Patients treated with surgery showed a higher fusion rate and shorter bony healing time than patients who received HVI. However, prospective studies are needed in the future to define better opti mal treatment and cost-effective perspective for the treatment of odontoid fractures.

PURPOSE Upper cervical fractures can heal with conservative treatments such as halo-vest immobilization (HVI) and Minerva jackets without surgery. The most rigid of these, HVI, remains the most frequently used treatment in many centers despite its relatively high frequency of orthosis-related complications. We conducted this study to investigate the clinical outcome, effectiveness, patient satisfaction, and associated complications of HVI. MATERIALS AND METHODS From April 1997 to December 2008, we treated 23 patients for upper cervical spinal injuries with HVI. For analysis, we divided high cervical fractures into four groups, including C1 fracture, C2 dens fracture, C2 hangman's fracture, and C1-2 associated fracture. We evaluated the clinical outcome, complications, and patient satisfaction through chart reviews and a telephone questionnaire. RESULTS The healing rate for upper cervical fracture using HVI was 60.9%. In most cases, bony healing occurred within 16 weeks. Older patients required longer fusion time. We observed a 39.1% failure rate, and 60.9% of patients experienced complications. The most common complications were frequent pin loosening (34.8%; 8/23) and pin site infection (17.4%; 4/23). The HVI treatment failed in 66.7% of patients with pin site problems. The patient approval rate was 31.6%. CONCLUSION The HVI produced frequent complications and low patient satisfaction. Bony fusion succeeded in 60.9% of patients. Pin site complications showed a tendency to influence the outcome of HVI, and would be promptly addressed to prevent treatment failure if they develop. The decision to use HVI requires an explanation to the patient of potential complications and constant vigilance to prevent such complications and unsatisfactory outcomes.