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A structure that possesses a continuous pore space packed with a granular material exhibits acoustic characteristics based on the principle similar to that of a porous material. Such a structure is used in low-noise pavement and ballast track. Therefore, predicting the sound absorption characteristics of a clearance generated in a granular material from the particle diameter and the physical property of gas is useful for engineering. This article deals with two packing models, namely, the simple cubic lattice model and the hexagonal lattice model, to measure the sound absorption coefficient of the structure packed with a granular material whose particle diameter is a few mm. Furthermore, a simple and accurate theoretical analysis that uses a one-dimensional transfer matrix method, which does not require numerous parameters, was performed. Comparing experimental values, when the particle diameter of the granular material was 4 mm, the percentage of the boundary layer in the clearance was moderately larger than when the diameter was 8 mm; therefore, the effect of viscosity on it was larger, and its sound absorption coefficient peak was higher. Moreover, compared with the simple cubic lattice, the hexagonal lattice had a higher percentage of boundary layer in the clearance because of its smaller volume of pore space. Then, the influence of friction due to the viscosity on it was higher, and its sound absorption coefficient peak was higher. In addition, the theoretical values obtained by the proposed analysis method typically matched the experiment values.

Renal fibrosis compromises kidney function, and it is a risk factor for chronic kidney disease (CKD). CKD ultimately progresses to end-stage kidney disease that can be cured only by kidney transplantation. Owing to the increasing number of CKD patients, effective treatment strategies are urgently required for renal fibrosis. TGF-β is a well-established fibrogenic factor that signals through SMAD2/3 signaling pathway. It was shown that there is a cross-talk between TGF-β/SMAD and WNT/β-catenin signaling pathways in renal tubular epithelial cells, and that a WNT/β-catenin inhibitor, ICG-001, ameliorates TGF-β1induced renal fibrosis. IC-2, a derivative of ICG-001, has been shown to potently induce hepatocyte differentiation of human mesenchymal stem cells by inhibiting WNT/β-catenin signaling. In the present study, we examined the effect of ICG-001, IC-2, and IC-2 derivatives (IC-2-506-1, IC-2-506-2, IC-2-506-3, IC-2-Ar-Cl, IC-2-OH, IC-2-OTBS, and IC-2-F) on TGF-β1-induced SMAD activation and fibrogenic response in immortalized human renal tubular epithelial HK-2 cells. All these compounds inhibited LiCl-induced WNT/β-catenin reporter activation to a similar extent, whereas ICG-001, IC-2-OTBS, and IC-2-F almost completely suppressed TGF-β1-induced SMAD reporter activation without apparent cytotoxicity. Phosphorylation of SMAD2/3 by TGF-β1 was more potently inhibited by IC-2-OTBS and IC-2-F than by ICG-001 and IC-2. IC-2-F suppressed TGF-β1-induced COL1A1 protein expression, whereas IC-2-506-1 and IC-2-OTBS suppressed TGF-β1-induced epithelial-mesenchymal transition. These results demonstrated that IC-2 derivatives suppress the TGF-β1-induced fibrogenic response of tubular epithelial cells and thus could be promising therapeutic agents for the treatment of renal fibrosis.

There was a previous study to derive the sound absorption coefficient of the powder layers comprising powder particles with a diameter of a few tens of μm. According to this previous method, the impact of air viscosity at the boundary layer generated in the pores between the powder particles is neglected. Therefore, precision is not guaranteed when the particle diameter is relatively large or when the density is relatively high. In the present study, to obtain the sound absorption coefficient of the powder layer more accurately, in addition to the above-described longitudinal vibration mode, the energy damping property of the boundary layer viscosity was calculated using the transfer-matrix method. As a result, when the longitudinal vibration mode and boundary layer viscosity were considered, the theoretical value tended to be closer to the experimental value than when only the longitudinal vibration was considered.

Amorphous solid dispersion (ASD) is one of the most promising formulation technologies for improving the oral absorption of poorly soluble drugs, where the maintenance of supersaturation plays a key role in enhancing the absorption process. However, quantitative prediction of oral absorption from ASDs is still difficult. Supersaturated solutions can cause liquid-liquid phase separation through the spinodal decomposition mechanism, which must be adequately comprehended to understand the oral absorption of drugs quantitatively. In this study, albendazole (ALZ) was formulated into ASDs using three types of polymers, poly(methacrylic acid-co-methyl methacrylate) (Eudragit) L100, Vinylpyrrolidone-vinyl acetate copolymer (PVPVA), and hydroxypropyl methylcellulose acetate succinate (HPMCAS). The oral absorption of ALZ in rats administered as ASD suspensions was not explained by dissolution study but was predicted using liquid-liquid phase separation concentration, which suggested that the absorption of ALZ was solubility-limited. The oral administration study in dogs performed using solid capsules demonstrated the low efficacy of ASDs because the absorption was likely to be limited by dissolution rate, which indicated the importance of designing the final dosage form of the ASDs.

In this study, a method of modeling the frequency characteristic of a ball-screw-driven stage in a design phase is proposed, targeting a printed-circuit-board drilling machine. A ball-screw driven stage is widely used as a precise positioning mechanism mounted in inspection devices or manufacturing equipment. When a controller of the stage is being designed, the frequency response of the stage is needed first, and it is generally measured with actual stage equipment. Therefore, the positioning performance of the stage cannot be estimated in the design phase. A method for predicting the frequency characteristic of the stage on the basis of its design specification is required for developing the stage structure and controller and the method will be useful for shortening development period or lowering development costs. At the beginning of this study, it was revealed that the frequency response of the stage is affected by not only the stiffness of the ball screw but the natural modes of the structure, and it cannot be represented with just a lumped-parameter model of the ball- screw driving system. Subsequently, a modeling method for a ball-screw driven stage was proposed. The model consists of a lumped-parameter model of a ball-screw drive system and vibration models of its structural components (which are analyzed by FEM models), and these models are connected by mode synthesis. Finally the effectiveness of the proposed model was demonstrated in comparison with experimental results, and it is concluded that the proposed model can represent similar frequency-response characteristics as represented by measured values.

Although amorphous solid dispersion (ASD) is widely recognized as a formulation technology to improve oral absorption of poorly soluble drugs, prediction of its oral absorption behavior from in vitro dissolution tests is still difficult. This becomes especially challenging for drugs with high crystallization tendency, because crystallization during dissolution tests and in the gastrointestinal tract makes dissolution and precipitation behaviors complex. In this study, attempts were made to explain the oral absorption behavior of griseofulvin (GF), a drug with high crystallization tendency, from ASDs using in vitro supersaturation and dissolution tests with a focus on the effect of the degree of supersaturation. Liquid-liquid phase separation of a supersaturated GF solution in the presence of vinylpyrrolidone-vinyl acetate copolymer (PVPVA), Eudragit (Poly(methacrylic acid-co-methyl methacrylate)) L100-55 (Eudragit), or hydroxypropyl methylcellulose acetate succinate (HPMCAS) was investigated based on turbidity measurements to find that the apparent phase separation concentration was increased in the presence of all polymers. In both the dissolution test and oral absorption study, a significant effect of the degree of supersaturation was observed presumably because of high crystallization tendency of GF. Thus, dose setting in the dissolution test was important to achieve an in vitro-in vivo correlation of GF ASDs. Other conditions required for the in vivo predictive dissolution study included pH-shift and surfactant addition. The apparent liquid-liquid phase separation concentration also worked as a rough predictor of the oral absorption of GF from ASD.

Uterine hemorrhage is a major complication associated with abortion. There are various causes of postabortion uterine hemorrhage. The objective of this article is to estimate the efficacy of three-dimensional computed tomography (3D-CT) angiography in the diagnosis of this condition. We present 3 case reports of women with massive genital bleeding after abortion. 3D-CT angiography clearly demonstrated the 3-D features of the feeding artery, the draining vein, and the surrounding normal structures. The diagnosis in patient 1 was a uterine arteriovenous malformation, in patient 2 was a placental polyp mimicking a uterine arteriovenous malformation, and in patient 3 was a placental polyp. Patients were all successfully treated with uterine artery embolization or transcervical resection of the placental polyp. We conclude that 3D-CT angiography is useful for making a differential diagnosis and for preoperative planning in patients with postabortion uterine hemorrhage.

The purpose of this paper is to examine how much the regional distribution of human capital affects the interregional wage differentials in Japan. To measure the impact of them, the Gini coefficient was simulated in case where there was no difference in the distribution of human capital between prefectures and compared with the actual value. The result shows that more than half of the actual Gini coefficients can be explained by the regional distribution of human capital.

The formability, current-voltage characteristics and stability of the planar lipid bilayer membranes from the synthetic phytanyl-chained glycolipids, 1, 3-di-O-phytanyl-2-O-(beta-glycosyl)glycerols (Glc(Phyt)(2), Mal(N)(Phyt)(2)) were studied. The single bilayer membranes were successfully formed from the glycolipid bearing a maltotriosyl group (Mal(3)(Phyt)(2)) by the folding method among the synthetic glycolipids examined. The membrane conductance of Mal(3)(Phyt)(2) bilayers in 100 mM KCl solution was significantly lower than that of natural phospholipid, soybean phospholipids (SBPL) bilayers, and comparable to that of 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) bilayers. From the permeation measurements of lipophilic ions through Mal(3)(Phyt)(2) and DPhPC bilayers, it could be presumed that the carbonyl groups in glycerol backbone of the lipid molecule are not necessarily required for the total dipole potential barrier against cations in Mal(3)(Phyt)(2) bilayer. The stability of Mal(3)(Phyt)(2) bilayers against long-term standing and external electric field change was rather high, compared with SBPL bilayers. Furthermore, a preliminary experiment over the functional incorporation of membrane proteins was demonstrated employing the channel proteins derived from octopus retina microvilli vesicles. The channel proteins were functionally incorporated into Mal(3)(Phyt)(2) bilayers in the presence of a negatively charged glycolipid. From these observations, synthetic phytanyl-chained glycolipid bilayers are promising materials for reconstitution and transport studies of membrane proteins.

In this work, we attempt to correlate the distribution of activation energy of hydrogen desorption for supported nickel catalysts with activity in a structure-sensitive reaction of ethane hydrogenolysis. It is known that ethane hydrogenolysis activity is not simply correlated by the size of metal particles of catalysts (Sinfelt, 1970; Ponec and Bond, 1996). From a practical point of view, a good parameter for correlating and predicting the activities of industrial catalysts is needed. We have examined the possibility of the activation energy distribution for this purpose.

From measurements of IR, HPLC, DSC, X-ray diffraction and solubility, the mechanical complex formation of ibuprofen (IP) with β-cyclodextrin (βCD) is closely examined. The roll-mixing products were transformed readily to an amorphous form. The carbonyl stretching band of IP shifted from 1718 cm −1 to 1812 cm −1 due to the complex formation with βCD under roll mixing. The complex yield of IP increased to 90% conversion at the roll-mixing period of 10 min at a shear rate of 2.1×10 3 (s −1 ). The apparent stability constant of the IP complex with βCD was enhanced about 10 times by roll mixing. From these facts, the inclusion complex formation of IP was expected to occur in solid-phase roll-mixing systems with βCD and other CDs.

The roles of Mg and Ca promoters in Ni-catalyzed hydrogasification of carbon were investigated with emphasis on nickel dispersion and nickel-carbon interactions during gasification. The dispersion of nickel on carbon, which was estimated by means of XRD, H 2 -TPD, and CO methanation test, was (Ni + Mg)a(Ni + Ca)>Ni. The increased dispersions of nickel by the Mg and Ca added were found to result in the enhanced NiC interaction, which was monitored through the desorption of CO from oxygen remaining on carbon, and, therefore, in the promotions of Ni-catalyzed lower-temperature gasification at 400 ≈ 700°C. The Ca promoter was likely to give surface CaO(OOO) species upon heating up to 550°C and release CO 2 above ≈650°C. The CO 2 released is efficiently converted by the nickel adjacent to CaO into CO to create Ni(OC species above 700°C, resulting in acceleration of Ni-catalyzed gasification above 700°C. In situ oxygen transfer to Ni/C during reaction is the most important role played by the Ca promoter.

Insulin resistance is considered as part of the pathogenesis of polycystic ovary syndrome (PCOS), and PCOS patients often show hyperinsulinemia. The influence of insulin on folliculogenesis in women with PCOS has not been fully investigated.Our objective was to assess the induction of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression with insulin treatment and effects of PTEN on IGF-I-induced granulosa cell proliferation as well as the correlation of PTEN levels with the concentration of insulin in follicular fluid in PCOS and non-PCOS patients. DESIGN, SETTING, PATIENTS, AND MAIN OUTCOME MEASURES: A cell proliferation assay, real-time RT-PCR, and Western blotting for PTEN, Akt, and ERK1/2 were conducted in primary cultured granulosa cells under IGF-I stimulation with or without insulin pretreatment. Phosphorylation of Akt and ERK1/2 was also determined by Western blotting. We also measured the insulin concentration in follicular fluid and the levels of PTEN expression in granulosa cells collected at the time of oocyte retrieval of in vitro fertilization in PCOS (n = 13) and non-PCOS patients (n = 37).PTEN expression was induced by insulin. Pretreatment with insulin attenuated the IGF-I-induced Akt phosphorylation and cell proliferation but not ERK1/2 phosphorylation. A phosphatidylinositol 3-kinase inhibitor, LY294002, inhibited the IGF-I-induced cell proliferation. Suppression of insulin-induced PTEN expression using small interfering RNA recovered IGF-I-induced Akt phosphorylation. PTEN levels in granulosa cells, which tended to be higher in PCOS patients, were correlated with the insulin concentration in follicular fluid.PTEN may influence the proliferation of human granulosa cells as well as disturbance of follicular growth in PCOS patients.

Granulosa cells proliferate and then undergo differentiation; an inverse relationship between these processes is observed during terminal follicular growth. During terminal follicular growth and initial luteinization, there is a necessary transition of granulosa cells to a less proliferative and highly steroidogenic form in response to LH. Although the expression of several molecules has been reported to be up-regulated by LH, proliferation/differentiation transition is not fully understood. Here, we show that the expression of a tumor suppressor, phosphatase and tensin homologue deleted on chromosome 10 (PTEN) was induced with human chorionic gonadotropin (hCG) treatment in human luteinized granulosa cells. Pretreatment with hCG attenuated insulin-like growth factor (IGF)-1-induced phosphorylation of AKT and cell proliferation, not phosphorylation of ERK1/2. Moreover, suppression of hCG-induced PTEN expression with siRNA increased AKT phosphorylation and cell proliferation in response to IGF1. We also demonstrate that a PI3K inhibitor, LY294002, not a MEK inhibitor, PD98059, inhibited IGF1-induced cell proliferation. In conclusion, PTEN induced to express by hCG in luteinized granulosa cells that inactivates AKT, not ERK, and attenuates IGF1-induced cell proliferation. PTEN expression may be a trigger for proliferation/differentiation transition in human granulosa cells.