Radiative properties of spectral selective coatings pigmented with TiO2 nanoparticles

This study is concerned with nanoparticle‐pigmented coatings used to control the radiative properties of surfaces exposed to sunlight. The desired coatings increase the near infrared reflectance while decreasing the reflectance of visible light. Both experimental and numerical approaches were followed in achieving the desired spectral behavior. In this study the pigmented coatings were made using TiO₂ as dispersed particles, clear acryl synthetic as the matrix, and standard black paper as the substrate. The spectral reflectance was measured by spectroscopy in the visible and near‐infrared regions. The effects of the size distribution and volume fraction of pigment particles and the coating thickness on the spectral reflectance of pigmented coatings are examined in this study. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20392     

Estimation of temperature distribution in biological tissue by using solutions of bioheat transfer equation

A living body has a system for maintaining its temperature. We have investigated the heat transfer characteristics common to each organ and therapy using heat transfer. The one‐dimensional bioheat transfer equation with bioheat generation was converted into a dimensionless form and solved by Laplace transformation on the assumption that biological tissue is homogeneous. A dimensionless steady‐state solution and transient solution were derived analytically. These solutions can represent the characteristics of the temperature distribution common to each organ. Comparison with numerical solutions has confirmed that these solutions can be applied to estimate the temperature distribution of inhomogeneous biological tissue. It is proved that the size of the region where temperature change occurs, the steady‐state thermal penetration depth, is decided by biological properties. Furthermore, the time needed to reach a steady state, or the time it takes for biological tissue to reach a steady state, is calculated by using these solutions. Additionally, a temperature chart was proposed for each organ or tissue. This chart can serve as a guideline for medical doctors in formulating thermal therapy. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(6): 374– 386, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20210     

Delayed hepatic signal recovery on ferucarbotran-enhanced magnetic resonance images: an experimental study in rat livers with gadolinium chloride-induced Kupffer cell damage

Objective

Hepatic signal recovery, rather than reduction, in ferucarbotran-enhanced magnetic resonance imaging (MRI) is a potential diagnostic marker of liver damage. We investigated hepatic signal recovery in rats with gadolinium chloride (GdCl₃)-induced Kupffer cell (KC) damage.

Materials and methods

Twelve rats received 8 μmol iron/kg of ferucarbotran 1 day after 0–7.5 mg/kg GdCl₃ injection (experiment A). Another 12 rats received ferucarbotran followed by GdCl₃ injection 6 h later (experiment B). In each experiment, three rats without GdCl₃ (“no injury group”) served as control. Another six rats received GdCl₃ alone without ferucarbotran. Hepatic signals were assessed on T ₂ ^* -weighted images for up to 29 days. Iron deposits were histologically examined on day 29.

Results

Hepatic signal recovery was delayed in a GdCl₃ dose-dependent manner in experiment A. Gadolinium chloride alone reduced hepatic signal 15 % during this experiment. Hepatic signal recovery was delayed only in rats that received 7.5 mg/kg GdCl₃ in experiment B. Hepatic signals negatively correlated with iron deposits in KCs and hepatocytes.

Conclusion

Hepatic signal recovery on ferucarbotran-enhanced MRI was delayed in the context of GdCl₃-induced KC damage due to increased hepatic iron deposits. Hepatic signal recovery may be used as a clinical marker of KC damage in liver disorders, including radiation-induced hepatitis.     

Effects of oil-droplet diameter on the stability of squalene oil in spray-dried powder

ABSTRACT

Effects of the oil-droplet diameter and emulsification with polymerized sodium caseinate (PNC) on the stability of squalene oil (SQ) retention in spray-dried powder were investigated. The SQ droplet diameter significantly affected the stability of the oil in spray-dried powders. The degradation behavior of SQ powders at 105°C was correlated using the Avrami equation. This oxidation mechanism may occur because of the propagative transfer of radical oxidation between oil-droplet particles. SQ emulsified with 5?wt% PNC and small oil droplets had better oxidative stability when compared with 3?wt% sodium caseinate.     

Low temperature growth of sol-gel SrBi2Ta2O9 thin films by low-pressure annealing

A new low-temperature processing method to prepare SrBi₂Ta₂O₉ thin films is proposed. These thin films were prepared on Pt/Ta/SiO₂/Si substrates by a sol-gel method, and their structural and electrical properties were investigated. Films were annealed before and after the top Pt electrode deposition. The first annealing was performed in a 760-Torr oxygen atmosphere at 600 °C for 30 min, and the second annealing was performed in a 5-Torr oxygen atmosphere at 600 °C for 30 min. The films were well crystallized and fine-grained after the second annealing. The electrical characteristics of the 200-nm-thick film obtained by this new process were as follows: remanent polarization, P_r = 8.5 μC/cm²; coercive field, E_c = 36 kV/cm; and leakage current density, I_L = 1 × 10⁻⁷ A/cm² (at 150 kV/cm). This process is very attractive for highly integrated ferroelectric nonvolatile memory applications. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(2): 27–33, 1997     

Lifestyle change and energy use in Japan: Household equipment and energy consumption

Energy use in the Japanese residential sector has more than doubled (on a per-household basis) during the post-war period. Important factors contributing to the increase include changes in the types of housing built, heating, cooling, water-heating equipment, and other appliances. In this paper, the developments of household equipment and living conditions in Japan are described, from their 1950s state to the present. Trends in energy consumption by fuel types and end uses are reviewed over the same period. The past trends are combined with expectations for future developments in household equipment and quality, as well as with international comparisons of household-energy use, to predict further increases in household-energy consumption. The results indicate the importance of a renewed emphasis on energy efficiency in the residential sector.     

Controlled Markov Set-chains with Set-valued Rewards—The Average Case

In this paper, the average case of finite state controlled Markov set-chains with R ^p -set-valued rewards are considered. The optimization is done by a pseudo-order relation on the set of all convex and compact subsets of R ^p induced by a closed convex cone. We introduce a v -step contractive property (minorization condition) for the average case and by use of this method the average expected reward set from a periodic policy is characterized. And, applying the scalarization technique, a Pareto optimal policy is obtained. Also, a numerical example is given to comprehend our results.     

Modelling of transition mechanisms from steady to oscillatory Marangoni flows in a liquid bridge configuration

In this paper, the transition mechanism from steady to oscillatory flow of Marangoni convection is investigated. Two-dimensional simulations for high Pr number fluids with several liquid bridge sizes were conducted in order to clarify the effect of temperature distribution on free surface upon the transition phenomena. The dependency of liquid bridge size on the onset of oscillatory flow was also evaluated. The results show that the formation of velocity distribution on the free surface is related to liquid bridge size and that it has a great influence on the onset of oscillation. From these results, a basic model for understanding the transition mechanism of Marangoni convection is proposed. In this transition model, the temperature distribution on the free surface was evaluated over a wide range of Pr numbers. A useful dimensionless parameter which indicates the onset of oscillation, the effective Marangoni number, is also proposed and evaluated.     

Electrocutaneous spatial integration at suprathreshold levels: An additive neural model.

The effects of cathode size on estimates of the magnitude of electrocutaneous stimulation were studied. The 24 Ss made magnitude estimates for combinations of 6 cathode sizes (2.5–3.0 mm diameter) and 5 currents (1.5–3.3 times the threshold). Estimates for small cathodes were consistently smaller but grew more rapidly than those for intermediate and large cathodes. From the results, contours were constructed showing how area and current trade off to maintain apparent intensity. These area–current contours suggest that supersummation prevails at low estimation levels and complete summation takes place at high levels. An additive neural model is proposed to account for the results and is also applied to other somatosensory systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Oligonucleotide-based gene therapy for cardiovascular disease

Gene therapy is emerging as a potential strategy for the treatment of cardiovascular disease such as restenosis after angioplasty, vascular bypass graft occlusion, transplant coronary vasculopathy, homozygous familial hypercholesterolemia and cystic fibrosis, for which no known effective therapy exists. Gene therapy requires efficient in vivo gene transfer technology. During the past decade, many gene transfer methods including viral transfer techniques have been developed, and some are being applied clinically in human gene therapy studies. Molecular biology and pathophysiology of the cardiovascular system have started to emerge, and the time is ripe for the introduction of gene therapy to the management of cardiovascular disorders. In this review, we have focused on the future potential of oligonucleotide-based gene therapy for the treatment of cardiovascular disease.