The objective of this experiment was to assess the relationship between electrical resistance of the vaginal mucosa and plasma progesterone for optimal mating time in the bitch. Eight mature beagle bitches were examined, and we observed eight times of estrus. Vaginal electric resistance was recorded weekly using a Draminski ovulation detector in anestrus, and daily in estrus. Plasma progesterone concentration was estimated by radioimmunoassay. In the bitch, incline in vaginal electric resistance (376.20 ± 105.63 units) showed a closely association with the onset of proestrus. Ovulation day was determined as the first day when plasma progesterone concentration increased above 5.0 ng/ml (Day 0). On Day 0, vaginal mucous electric resistance was 438 ± 132 units. Vaginal mucous electric resistance showed a slight decrease or was maintained until Day 0. However, it showed an explosive increase, and peaked on Day 1~3, which was above 600 units. Two of eight cases peaked on Day 1, three of eight cases were revealed on Day 2, and others were revealed on Day 3. After Day 4, resistance showed a rapid drop to below 600 units and reached 200 units on Day 8. The optimal mating time was determined when vaginal mucous electric resistance was above 600 units.

In this study, the detection characteristics of volatile organic compounds (VOCs) were investigated in relation to two different experimental approaches (direct injection (DI) vs. solid phase micro extraction (SPME)) based on effective carbon number (ECN) theory. To this end, the calibration data obtained by both methods were evaluated in association with split ratio (such as 1:1 (splitless), 1:5, 1:10, and 1:20) The calibration results of eight different target VOCs were examined in terms of relative sensitivity at a given split ratio. If slope values are derived between ECN and Response Factor (RF) values of each compound, the DI-based data obtained at 1:5 split ratio yielded slightly positive bias of +3.6% relative to theoretic values of 20%. Likewise, the results at 1:10 split condition showed +1.2% bias. In contrast, the SPME-based results showed significantly large biases. The result of this comparative study suggests the need for more deliberate QA procedure to obtain quantitative data for the SPME method.

Taste receptors of the anterior tongue are innervated by the chorda tympani (CT) branch of the facial (VIIth) nerve. The CT nerve transmits information on taste to the ipsilateral nucleus of the solitary tract (NST), which is the first taste central nucleus in the medulla. Taste information is known to be transferred ipsilaterally along the taste pathway in the central nervous system. Some patients with unilateral CT damage often retain their ability to sense taste. This phenomenon is not explained by the unilateral taste pathway. We examined whether neurons in the NST receive information on taste from the contralateral side of the tongue by measuring c-Fos-like Immunoreactivity (cFLI) following taste stimulation of the contralateral side of the tongue in the anesthetized rats. We used four basic taste stimuli, 1.0 M sucrose, 0.3 M NaCl, 0.01 M citric acid, 0.03 M QHCl, and distilled water. Stimulation of one side of the tongue with taste stimuli induced cFLI in the NST bilaterally. The mean number of cFLI ranged from 23.28 ± 2.46 by contralateral QHCl to 30.28 ± 2.26 by ipsilateral NaCl stimulation. The difference between the number of cFLI in the ipsilaterl and contralateral NST was not significant. The result of the current study suggests that neurons in the NST receive information on taste not only from the ipsilateral but also the contralateral side of the tongue.

This study aims to evaluate the relationship with the concentration and odor intensity using the odor sensory method for 5 types of aldehyde compounds and styrene. For the measurement, 13 panelists were selected by several criteria through a panel test. The estimation showed that the correlation of the concentration with odor intensity for the 12 compounds including of the sulfur compounds, ammonia, and trimethylamine can be reasonably expressed by the equation I = Aㆍlog C + B (I : odor Intensity, C : material concentration, A : material constant, B : constant). The equations show the sensivities of intensity change for the change of concentration. According to the increase of concentration the odor intensities for acetaldehyde and iso-valeraldehyde increase larger than for the other aldehydes. Regulation standards of 12 species of odor substance concentraton and odor intensity by using the correlation equation was reviewed for adequacy. It was evaluated that the regulation standards on site boundary in operation are too low for NH₃, DMDS, and iso-valeraldehyde and too high for TMA. The result of this study is suggested to be used as a base data for research on measures to improve the regulation standards for complex odor concentration on site boundary in operation.

Amoxicillin, a well-known antibiotic, has a broad spectrum against gram-negative and gram-positive bacteria. This experiment was conducted in order to investigate the effect of micronized and non-micronized amoxicillin prepared using different comminution techniques on change in blood concentration of rats. Forty adult male Sprague Dawley rats (6~7 weeks of age, body weight 128.3 ± 10.7 g) were randomly allocated to two treatment groups: micronized amoxicillin (MA) group treated with micronized amoxicillin trihydrate powder (particle size, over 90% of 10 μm), non-micronized amoxicillin (NMA) group treated with non-micronized amoxicillin trihydrate powder (particle size, over 70% of 100 μm), given 480 mg/kg body weight once daily for four days. The results showed a significant increase in serum concentration in the MA group on days 3 and 4, compared to the NMA group (P<0.05). In particular, serum concentration of the MA group on day 4 was increased almost two times that of the NMA group. The results indicate that due to the increase of the drug’s oral bioavailability, higher serum concentration would be achieved with the micronized amoxicillin trihydrate than with the non-micronized drug.

Cancer is the result of damage to the genetic system, i.e., dysfunction of the DNA repair system, resulting in dysregulated expression of various molecules, leading to cancer formation, migration, and invasion. In cancer progression, several proteases play a critical role in metastasis; however, their biological mechanism in cancer metastasis is not clearly understood. Among these proteases, cathepsins are a family of lysosomal proteases found in most animal cells. Cathepsins have an important role in protein turnover of mammalian, and are classified into 15 types based on their structure as serine (cathepsin A and G), aspartic (cathepsin D and E), and cysteine cathepsins (cathepsin B, C, F, H, K, L, O, S, V, X, and W). Cysteine cathepsins appear to accelerate the progression of human and rodent cancers, which can be a biomarker of the potency of malignancy or metastasis in mammalian. Overexpression of cyteine cathepsins causes the activation of angiogenesis promoting factor, whereas their downregulation reduces the angiogenesis of cancer progression. Under physiological conditions, cysteine cathepsins are essential in inflammation, infection, and cancer development. Activity of cysteine proteases, i.e., cathepsin B, is required for cancer progression or metastasis. Elevation of cysteine cathepsin is associated with cancer metastasis, angiogenesis, and immunity. Therefore, in this review, we suggest that cysteine cathepsin may be an anticancer target of strong clinical interest, although the exact mechanism of cathepsins in cancer metastasis is under investigation.

In this study, the experimental feasibility of alkali absorption method, recommended for the analysis of volatile fatty acids (VFA), was evaluated by considering the vaporization efficiency in relation to Henry’s law. Many experimental steps involved in the analysis such as absorption of VFA into the solution (as sorbent), extraction of absorbed VFA from solution, and SPME analysis of extracted vapor are all prone to biases. The extent of bias involved in the extraction stage is estimated under the simulated conditions of active purging at two temperature conditions of 25 and 90℃. The results of computation based on this simulated condition indicated that recovery rate of VFA from absorbed solution can be 1.1% and 30.2% after 1 hour of purging, respectively. As this low recovery rate is directly associated with low sensitivity and poor reproducibility, this official testing method is prone to various sources of experimental biases. Because of these limitations involved in VFA analysis, this official method cannot be used reliably to quantify the VFA in ambient air samples. Consequently, it is desirable to replace this method with the other verified method with more confidence such as the combined application of sorbent tube and thermal desorption.

Delamination crack detection is very important for improving the structural reliability of laminated composite structures. This requires real-time delamination detection technologies. For composite laminates that are reinforced with carbon fiber, an electrical potential method uses carbon fiber for reinforcements and sensors at the same time. The use of carbon fiber for sensors does not need to consider the strength reduction of smart structures induced by imbedding sensors into the structures. With carbon fiber reinforced (CF/) epoxy matrix composites, it had been proved that the delamination crack was detected experimentally. In the present study, therefore, similar experiments were conducted to prove the applicability of the method for delamination crack detection of CF/polyetherethereketone matrix composite laminates. Mode I and mode II delamination tests with artificial cracks were conducted, and three point bending tests without artificial cracks were conducted. This study experimentally proves the applicability of the method for detection of delamination cracks. CF/polyetherethereketone material has strong electric resistance anisotropy. For CF/polyetherethereketone matrix composites, a carbon fiber network is constructed, and the network is broken by propagation of delamination cracks. This causes a change in the electric resistance of CF/polyetherethereketone matrix composites. Using three point bending specimens, delamination cracks generated without artificial initial cracks is proved to be detectable using the electric potential method: This method successfully detected delamination cracks.

Well-distributed SnO2-Sn-Ag3Sn nanoparticles embedded in carbon nanofibers were fabricated using a co-electrospinning method, which is set up with two coaxial capillaries. Their formation mechanisms were successfully demonstrated. The structural, morphological, and chemical compositional properties were investigated by field-emission scanning electron spectroscopy (FESEM), bright-field transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). In particular, to obtain well-distributed SnO2 and Sn and Ag3Sn nanoparticles in carbon nanofibers, the relative molar ratios of the Ag precursor to the Sn precursor including 7 wt% polyacrylonitrile (PAN) were controlled at 0.1, 0.2, and 0.3. The FESEM, bright-field TEM, XRD, and XPS results show that the nanoparticles consisting of SnO2-Sn-Ag3Sn phases were in the range of ~4 nm-6 nm for sample A, ~5 nm-15 nm for sample B, ~9 nm-22 nm for sample C. In particular, for sample A, the nanoparticles were uniformly grown in the carbon nanofibers. Furthermore, when the amount of the Ag precursor and the Sn precursor was increased, the inorganic nanofibers consisting of the SnO2-Sn-Ag3Sn nanoparticles were formed due to the decreased amount of the carbon nanofibers. Thus, well-distributed nanoparticles embedded in the carbon nanofibers were successfully synthesized at the optimum molar ratio (0.1) of the Ag precursor to the Sn precursor after calcination of 800˚C.

The Ti-6Al-4V extra low interstitial (ELI) alloy has been widely used as an orthopedic implant material because of its excellent mechanical properties and biocompatibility. However, it still has many problems, including a high elastic modulus and toxicity of the Al and V elements. Therefore, non-toxic biomaterials with a low elastic modulus need to be developed. A high energy mechanical milling (HEMM) process is introduced to improve the effect of sintering. Rapid sintering of spark plasma sintering (SPS) under pressure was used to make an ultra fine grain of Ti-25 wt.%Nb-7 wt.%Zr-10 wt.%Mo-(10 wt.%CPP) composites with bio-attractive elements for increasing strength. These composites were fabricated by SPS at 1000˚C at 60 MPa using HEMM powders. During the sintering process, CaTiO3, TixOy, and CaO were formed because of the reaction between Ti and CPP. The effects of CPP content on the physical and mechanical properties of the sintered Ti-Nb-Zr-Mo-CPP composites were investigated. The biocompatibility and corrosion resistance of the Ti-Nb-Zr-Mo alloys were improved by the addition of CPP.

A study on the corrosion behavior of Inconel alloys and Incoloy 800H in molten salt of LiCl-Li2O was investigated at 650˚C for 24-312 hours in an oxidation atmosphere. The order of the corrosion rate was Inconel 600< Inconel 601< Incoloy 800H< Inconel 690. Inconel 600 showed the best performance suggesting that the content of Fe, Cr and Ni are the important factor for corrosion resistance in hot molten salt oxidation conditions. The corrosion products of Inconel 600 and Inconel 601 were Cr2O3 and NiFe2O4, In case of Inconel 690, a single layer of Cr2O3 was formed in the early stage of corrosion and an outer layer of NiFe2O4 and inner layer of Cr2O3 were formed with an increase of corrosion time. In the case of Incoloy 800H, Cr2O3 and FeCr2O4 were observed. Most of the outer scale of the alloys was observed to be spalled from the results of the SEM analysis and the unspalled scale which adhered to the substrate was composed of three layers. The outer layer, the middle one, and the inner one were Fe, Cr, and Ni-rich, respectively. Inconel 600 showed localized corrosion behavior and Inconel 601, 690 and Incoloy 800H showed uniform corrosion behavior. Ni improves the corrosion resistance and too much Cr and/or Fe content deteriorates the corrosion resistance.

The electrolytic reduction of a spent oxide fuel involves liberation of the oxygen in a molten LiCl electrolyte, which is a chemically aggressive environment that is too crosive for typical structural materials. Therefore, it is essential to choose the optimum material for the process equipment for handling a molten salt. In this study, the corrosion behavior of pyro-carbon made by CVD was investigated in a molten LiCl-Li2O salt under an oxidation atmosphere at 650˚C and 750˚C for 72 hours. Pyro-carbon showed no chemical reactions with the molten salt because of its low wettability between pyro-carbon and the molten salt. As a result of XRD analysis, pyro-carbon exposed to the molten salt showed pure graphite after corrosion tests. As a result of TGA, whereas the coated layer by CVD showed high anti-oxidation, the non-coated layer showed relatively low anti-oxidation. The stable phases in the reactions were C(S), Li2CO3(S), LiCl(l), Li2O at 650˚C and C(S), LiCl(l), Li2O(S) at 750˚C. Li2CO(S) was decomposed at 750˚C into Li2O(S) and CO2(g).

For fabricating silicon solar cells with high conversion efficiency, texturing is one of the most effective techniques to increase short circuit current by enhancing light trapping. In this study, four different types of textures, large V-groove, large U-groove, small V-groove, and small U-groove, were prepared by a wet etching process. Silicon substrates with V-grooves were fabricated by an anisotropic etching process using a KOH solution mixed with isopropyl alcohol (IPA), and the size of the V-grooves was controlled by varying the concentration of IPA. The isotropic etching process following anisotropic etching resulted in U-grooves and the isotropic etching time was determined to obtain U-grooves with an opening angle of approximately 60˚. The results indicated that U-grooves had a larger diffuse reflectance than V-grooves and the reflectances of small grooves was slightly higher than those of large grooves depending on the size of the grooves. Then amorphous Si:H thin film solar cells were fabricated on textured substrates to investigate the light trapping effect of textures with different shapes and sizes. Among the textures fabricated in this work, the solar cells on the substrate with small U-grooves had the largest short circuit current, 19.20 mA/cm2. External quantum efficiency data also demonstrated that the small, U-shape textures are more effective for light trapping than large, V-shape textures.

One of the most important characteristics of Mg alloys is the high ratio of strength to weight. This is why there is a high demand for applications with these alloys in the transportation industries to reduce the fuel consumption and to save energy. In addition, magnesium (and its alloys) is of considerable interest as a structural material, especially in the aerospace and automotive industries thanks to its low density. However, its major drawback is its high sensitivity to corrosion. Therefore, its use requires the application of a surface treatment. This study used a die-casted AZ91D Mg alloyand all the samples were annealed (in 120˚C). The surface microstructure and phase distribution in thin-walled AZ91D magnesium components cast on a hot-chamber die-casting machine were investigated by optical microscopy and scanning electron microscopy. The reflectance differences in the bulk state comparison with the annealing state are caused by hydrogenation presence of the Mg layer under an oxidation surface layer.

In this study, GaN powders were synthesized from gallium oxide-hydroxide (GaOOH) through an ammonification process in an NH3 flow with the variation of B2O3 additives within a temperature range of 300-1050˚C. The additive effect of B2O3 on the hexagonal phase GaN powder synthesis route was examined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transformation infrared transmission (FTIR) spectroscopy. With increasing the mol% of B2O3 additive in the GaOOH precursor powder, the transition temperature and the activation energy for GaN powder formation increased while the GaN synthesis limit-time (tc) shortened. The XPS results showed that Boron compounds of B2O3 and BN coexisted in the synthesized GaN powders. From the FTIR spectra, we were able to confirm that the GaN powder consisted of an amorphous or cubic phase B2O3 due to bond formation between B and O and the amorphous phase BN due to B-N bonds. The GaN powder synthesized from GaOOH and B2O3 mixed powder by an ammonification route through β-Ga2O3 intermediate state. During the ammonification process, boron compounds of B2O3 and BN coated β-Ga2O3 and GaN particles limited further nitridation processes.

Mg3-xZnxSb2 powders with x = 0-1.2 were fabricated by mechanical alloying in a planetary ball mill with a speed of 350 rpm for 24 hrs and then hot pressed under a pressure of 70 MPa at 773 K for 2 hrs. It was found that there were systematic shifts in the X-ray diffraction peaks of Mg3Sb2 (x = 0) toward a higher angle with increasing Zn for both the powder and the bulk sample and finally the phase of Mg1.86Zn1.14Sb2 was formed at the Zn content of x = 1.2. The Mg3-xZnxSb2 compounds had nano-sized grains of 21-30 nm for the powder and 28-66 nm for the hot pressed specimens. The electrical conductivity of hot pressed Mg3-xZnxSb2 increased with increasing Zn content and temperature from 33 Sm-1 for x = 0 to 13,026 Sm-1 for x = 1.2 at 323 K. The samples for all the compositions from x = 0 to x = 1.2 had positive Seebeck coefficients, which decreased with increasing Zn content and temperature, which resulted from the increased charge carrier concentration. Most of the samples had relatively low thermal conductivities comparable to the high performance thermoelectric materials. The dimensionless figure of merit of Mg3-xZnxSb2 was directly proportional to the Zn content except for the compound with Zn = 1.2 at high temperature. The Mg3-xZnxSb2 compound with Zn = 0.8 had the largest value of ZT, 0.33 at 723 K.

The study of grinding behavior characteristics on aluminum powders and carbon nano tubes (CNTs) has recently gained scientific interest due to their useful effect in enhancing advanced nano materials and components, which significantly improves the property of new mechatronics integrated materials and components. We performed a series of dry grinding experiments using a planetary ball mill to systematically investigate the grinding behavior during Al/CNTs nano composite fabrication. This study focused on a comparative study of the various experimental conditions at several variations of rotation speeds, grinding time and with and without CNTs. The results were monitored for the particle size distribution, median diameter, crystal structure from XRD pattern and particle morphology at a given grinding time. It was observed that pure aluminum powders agglomerated with low rotation speed and completely enhanced powder agglomeration. However, Al/CNTs composites were achieved at maximum experiment conditions (350 rpm, 60 min.) of this study by a mechanical alloy process for Al/CNTs mixed powders because the grinding behavior of Al/CNTs composite powder was affected by addition of CNTs. Indeed, the powder morphology and crystal size of the composite powders changed more by an increase of grinding time and rotation speed.

In this study, using a tin chloride solution as the raw material, a nano-sized tin oxide powder with an average particle size below 50 nm is generated by a spray pyrolysis process. The properties of the tin oxide powder according to the nozzle tip size are examined. Along with an increase in the nozzle tip size from 1 mm to 5 mm, the generated particles that appear in the shape of droplets maintain an average particle size of 30 nm. When the nozzle tip size increases from 1 mm to 2 mm, the average size of the generated particles is around 80-100 nm, and the ratio of the independent particles with a compact surface structure increases significantly. When the nozzle tip size is at 3 mm, the majority of the generated particles maintain the droplet shape, the average size of the droplet-shaped particles increases remarkably compared to the cases of other nozzle tip sizes, and the particle size distribution also becomes extremely irregular. When the nozzle tip size is at 5 mm, the ratio of droplet-shaped particles decreases significantly and most of the generated particles are independent ones with incompact surface structures. Along with an increase in the nozzle tip size from 1 mm to 3 mm, the XRD peak intensity increases, whereas the specific surface area decreases greatly. When the nozzle tip size increases up to 5 mm, the XRD peak intensity decreases significantly, while the specific surface area increases remarkably.

We evaluated whether group locomotor imagery training-combined knowledge of performance (KP) lead to improvements in gait function in community dwelling individuals with chronic stroke. Ten adults who had suffered a hemiparetic stroke at least 6 months earlier participated in group locomotor imagery training-combined KP for 5 weeks, twice per week, with 2 h intensive training. Dynamic gait index scores increased significantly after the group locomotor imagery training-combined KP. However, times for the timed up-and-go test did not improve significantly after the training. Group locomotor imagery training-combined KP may be a useful option for the relearning of gait performance for community dwelling individuals with chronic hemiparetic stroke.

The purposes of this study were to develop a new orthosis controlling ankle and knee joint motion during the gait cycle and to identify the effects of the newly designed orthosis on gait kinematics and tempospatial parameters, including coordination of the extremities in stroke patients. Fifteen individuals who had sustained a stroke, onset was 16 months, participated in this study. Before application of the measurement equipment the subjects were accustomed to walking on the ankle-foot orthosis (AFO) or stance control knee with knee flexion assisted-oil damper ankle-foot orthosis (SCKAFO) for 5 minutes. Fifteen patients were investigated for 45 days with a 3-day interval between sessions. Measurements were walking in fifteen stroke with hemiparesis on the 3D motion analysis system. Comparison of AFO and SCKAFO are gait pattern. The difference between the AFO and SCKAFO conditions was significant in the gait velocity, step length of the right affected side, stance time of both legs, step-length asymmetry ratio, single-support-time asymmetry ratio, -thigh angle and -shank angle in the mid swing (p<.001). Using a SCKAFO in stroke patients has shown similar to normal walking speeds can be attained for walking efficiency and is therefore desirable. In this study, the support time of the affected leg with the SCKAFO was longer than with the AFO and the asymmetry ratio of single support time decreased by more than with the AFO. This indicates that the SCKAFO was effective for improving gait symmetry, single-support-time symmetry. This may be due to the decrease of gait asymmetry. Thus, the newly designed SCKAFO may be useful for promoting gait performance by improving the coordination of the extremity and decreasing gait asymmetry in chronic stroke patients.