Withdrawal of [corrected] estrogen increases hypothalamic neuropeptide Y (NPY) mRNA expression in ovariectomized obese rat

We determined the changes in neuropeptide Y (NPY) mRNA expression of the arcuate nucleus (ARC) in sham-operated (SHAM) and bilaterally ovariectomized (OVX) rats with estradiol (E2) supplement. Ovariectomy increases body weight gain for 3 weeks, accompanied by an increase of daily food intake. Ovariectomy significantly reduced serum corticosterone levels. E2 supplement reversed the effects of ovariectomy on body weight gain, food intake and serum corticosterone levels. Ovariectomy significantly increased NPY mRNA expression in the ARC. E2 supplement decreased NPY mRNA expression in the ARC of OVX rats. The present findings indicated that hypothalamic NPY mRNA expression, which involves the regulation of feeding behavior, are in parallel with circulating estrogen levels. Hypothalamic NPY mRNA expression may be important in the induction of hyperphagia after the withdrawal of estrogen by bilateral ovariectomy.     

On the capacity of two-dimensional run-length constrained channels

Two-dimensional binary patterns that satisfy one-dimensional (d, k) run-length constraints both horizontally and vertically are considered. For a given d and k, the capacity C_d,k is defined as C_d,k=lim_m,n→∞log₂N_m,n ^d,k/mn, where N_m,n^d,k denotes the number of m×n rectangular patterns that satisfy the two-dimensional (d,k) run-length constraint. Bounds on C_d,k are given and it is proven for every d⩾1 and every k>d that C_d,k=0 if and only if k=d+1. Encoding algorithms are also discussed     

The phase state at high temperatures in the MOX-SiO2 system

Influence of impurity Si on microstructure in a plutonium and uranium mixed oxide (MOX), which is used for fast breeder reactor fuel, was investigated, and phase state in 25% SiO₂ - (U_0.7Pu_0.3)O₂ was observed as a function of oxygen chemical potential. Compounds composed of Pu and Si with other elements were observed at grain boundaries of the MOX parent phase in the specimens after annealing. These compounds were not observed in the grain interior and the MOX phase was not affected significantly by impurity Si. It was found that the compounds tended to form more observably with decreasing O/M ratio and with increasing annealing temperatures.     

A BiCMOS PLL-based data separator circuit with high stability andaccuracy

A data separator that can work in Winchester disk drives at a read/write speed of up to 30 Mb/s is described. To realize high stability and accuracy in reproducing data in high-speed transfers, a digital synchronization field detector and an analog dual-mode phase-locked loop (PLL) that has a phase detector which has constant gain in the data field, independent of pattern, are used. The dual-mode analog PLL has a wide decode margin, locks up quickly, and operates stably without being affected by the frequency deviation of data. The digital sync field detector is adjustment-free and detects sync fields very accurately. The IC incorporates a RLL 2-7 code encoder/decoder and a write compensator. Use of the 2-μm BiCMOS process keeps the total power consumption as low as 400 mW even at the high transfer rate of 30 Mb/s     

Effects of transforming growth factor beta on corneal epithelial and stromal cell function in a rat wound healing model after excimer laser keratectomy

BACKGROUND: Transforming growth factor beta (TGF-beta) regulates extracellular matrix deposition, cell proliferation, and migration, and is expressed in cornea. TGF-beta is thought to be involved in the corneal wound healing process. METHODS: The central corneal area (3 mm in diameter) of Lewis rats was ablated using PTK mode excimer laser and the wound healing process was observed at 12 and 24 h and 2, 5, 10, and 30 days after treatment. The expression of TGF-beta 1, -beta 2 and -beta 3, TGF-beta type I and type II receptors, alpha 3, alpha 5, beta 4 integrin subunits, laminin and fibronectin was studied immunohistochemically. Antibody neutralizing TGF-beta 1, -beta 2 and -beta 3 was administered intraperitoneally, 50 micrograms daily, for 5 days after the laser treatment to investigate the effects of TGF-beta function blockade. RESULTS: At the leading edge of the regenerating epithelium, no TGF-beta type I and type II receptors and beta 4 integrin subunits were expressed after 24 h. Regenerating epithelium covered the ablated area after 2 days. An abnormal fibrotic layer was formed in the subepithelial area. This layer contained round-shaped cells in the stroma in the early stage (2-5 days after laser ablation) and spindle-shaped fibroblast-like keratocytes after 10 days. Laminin and fibronectin expression increased in the fibrotic layer. The increased stromal cells expressed TGF-beta isoforms and TGF-beta receptors. Neutralizing TGF-beta inhibited the stromal cell increase in the laser ablated area after 5 days. CONCLUSION: TGF-beta may be involved in epithelial cell migration and stromal cell reaction during the corneal wound healing process after excimer laser ablation in rat models.     

Structure and optical properties of ZnSeO alloys with O composition up to 6.4%

II–VI-O type alloy semiconductor ZnSeO (O composition up to 6.4%) is grown by molecular beam epitaxy. O composition increases with O₂ flow rate. Several XRD peaks are observed when O composition is 2–4%, indicating phase separation. Growth at low temperature results in higher O composition. Photoluminescence intensity of ZnSeO lattice matched to GaAs is much stronger than that of ZnSe and peak shifts to lower energies with increasing O composition. Photoreflectance spectroscopy is performed to investigate the band gap energy. The band gap energy investigated by photoreflectance decreases with increasing O composition due to large band gap bowing even when phase separation occurs. The bowing parameter is estimated as 8.4 eV.     

A Precomputed Approach for Real-Time Haptic Interaction with Fluids

The key to enhancing perception of the virtual world is improving mechanisms for interacting with that world. Through providing a sense of touch, haptic rendering is one such mechanism. Many methods efficiently display force between rigid objects, but to achieve a truly realistic virtual environment, haptic interaction with fluids is also essential. In the field of computational fluid dynamics, researchers have developed methods to numerically estimate the resistance due to fluids by solving complex partial differential equations, called the Navier-Stokes equations. However, their estimation techniques, although numerically accurate, are prohibitively time-consuming. This becomes a serious problem for haptic rendering, which requires a high frame rate. To address this issue, we developed a method for rapidly estimating and displaying forces acting on a rigid virtual object due to water. In this article, we provide an overview of our method together with its implementation and two applications: a lure-fishing simulator and a virtual canoe simulator     

Reduction in total surface area by the develpment of microdroplets during dewetting

To meet the demand of an increasing storage density, the lubricant film for the head disk interface (HDI) needs to be thinner and stronger. In recent years, a new head/disk system, such as the contact type, has been proposed. It is reported that PFPE Zdol coated on a magnetic disk is dewetted and microdroplets are formed due to polar interactions. This makes a flying magnetic head unstable, therefore, the physics and chemistry of the dewetting phenomenon are topics of current interest. We investigated the formation and development of microdroplets using an atomic force microscope (AFM) and an optical microscope. First, we observed the disk surface coated with PFPE Zdol by AFM. From the cross section images of the microdroplets, we found that the microdroplets had a shape similar to a sphere. With this finding, we estimated the contact angle of the microdroplets in each image. The results showed that the contact angle of the microdroplet gradually decreased with time, which indicated the existence of a PFPE thin film in the dewetted area. The thickness of the PFPE film in the dewetted area was then measured using an elliposometer. Next, we investigated the variation in the number and the average diameter of the microdroplets during dewetting using images observed by the optical microscope. The total surface area change was also calculated from the observed results, and it was found that the total surface area, namely the sum of the microdroplet surfaces and dewetted area, was reduced by the development of the microdroplets.