Perfluorooctane Sulfonate (PFOS) and Related Perfluorinated Compounds in Human Maternal and Cord Blood Samples: Assessment of PFOS Exposure in a Susceptible Population during Pregnancy

Fluorinated organic compounds (FOCs), such as perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorooctane sulfonylamide (PFOSA), are widely used in the manufacture of plastic, electronics, textile, and construction material in the apparel, leather, and upholstery industries. FOCs have been detected in human blood samples. Studies have indicated that FOCs may be detrimental to rodent development possibly by affecting thyroid hormone levels. In the present study, we determined the concentrations of FOCs in maternal and cord blood samples. Pregnant women 17–37 years of age were enrolled as subjects. FOCs in 15 pairs of maternal and cord blood samples were analyzed by liquid chromatography–electrospray mass spectrometry coupled with online extraction. The limits of quantification of PFOS, PFOA, and PFOSA in human plasma or serum were 0.5, 0.5, and 1.0 ng/mL, respectively. The method enables the precise determination of FOCs and can be applied to the detection of FOCs in human blood samples for monitoring human exposure. PFOS concentrations in maternal samples ranged from 4.9 to 17.6 ng/mL, whereas those in fetal samples ranged from 1.6 to 5.3 ng/mL. In contrast, PFOSA was not detected in fetal or maternal samples, whereas PFOA was detected only in maternal samples (range, < 0.5 to 2.3 ng/mL, 4 of 15). Our results revealed a high correlation between PFOS concentrations in maternal and cord blood (r(2) = 0.876). However, we did not find any significant correlations between PFOS concentration in maternal and cord blood samples and age bracket, birth weight, or levels of thyroid-stimulating hormone or free thyroxine. Our study revealed that human fetuses in Japan may be exposed to relatively high levels of FOCs. Further investigation is required to determine the postnatal effects of fetal exposure to FOCs

カラギーナンゲルを用いた組織等価MRIフｧントムの開発

A new tissue-equivalent MRI phantom based on carrageenan gel was developed. Carrageenan gel is an ideal solidifying agent for making large, strong phantoms in a wide variety of shapes. GdCl(3) was added as a T(1) modifier and agarose as a T(2) modifier. The relaxation times of a very large number of samples were estimated using 1.5-T clinical MRI equipment. The developed phantom was found to have a T(1) value of 202-1904 ms and a T(2) value of 38-423 ms when the GdCl(3) concentration was varied from 0-140 mumol/kg and the agarose concentration was varied from 0-1.6% in a carrageenan concentration that was fixed at 3%. The range of measured relaxation times covered those of all types of human tissue. Empirical formulas linking the relaxation time with the concentration of the modifier were established to enable the accurate and easy calculation of the modifier concentration needed to achieve the required relaxation times. This enables the creation of a phantom having an arbitrary combination of T(1) and T(2) values and which is capable of retaining its shape

Recurrence after Spontaneous Resolution of an Idiopathic Epiretinal Membrane

We report a case of recurrent epiretinal membrane (ERM) after spontaneous resolution of an idiopathic ERM. A 65-year-old female demonstrated a spontaneous improvement in visual acuity from 0.1 to 1.2 in her left eye attributable to spontaneous resolution of idiopathic ERM due to posterior vitreous detachment. Thereafter, however, her visual acuity again decreased to 0.2 because of the recurrence of ERM. Her visual acuity improved to 0.8 after surgical removal. A microscopic examination of the excised specimen showed a characteristic undulating internal limiting membrane (ILM) and a continuous sheet of cells overlying the inner surface of the ILM. This case report illustrates that although spontaneous ERM resolution is rare, there is a possibility of recurrence even after spontaneous ERM resolution

Molecular database for classifying Shorea species (Dipterocarpaceae) and techniques for checking the legitimacy of timber and wood products

The extent of tropical forest has been declining, due to over-exploitation and illegal logging activities. Large quantities of unlawfully extracted timber and other wood products have been exported, mainly to developed countries. As part of the export monitoring effort, we have developed methods for extracting and analyzing DNA from wood products, such as veneers and sawn timbers made from dipterocarps, in order to identify the species from which they originated. We have also developed a chloroplast DNA database for classifying Shorea species, which are both ecologically and commercially important canopy tree species in the forests of Southeast Asia. We are able to determine the candidate species of wood samples, based on DNA sequences and anatomical data. The methods for analyzing DNA from dipterocarp wood products may have strong deterrent effects on international trade of illegitimate dipterocarp products. However, the method for analyzing DNA from wood is not perfect for all wood products and need for more improvement, especially for plywood sample. Consequently, there may be benefits for the conservation of tropical forests in Southeast Asia. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10265-010-0348-z) contains supplementary material, which is available to authorized users

ROBUST PRODUCT DESIGN OPTIMIZATION METHOD USING HIERARCHICAL REPRESENTATIONS OF CHARACTERISTICS

ABSTRACT Product design optimizations usually require the optimization of not only all performance characteristics, but also the robustness of certain performance characteristics. Obtaining optimum design solutions is far from easy, since this requires evaluations of numerous related characteristics that usually have complicated and conflicting interrelationships. Some of these characteristics can include variations of one type or another, such as manufacturing process variations, variations pertaining to the environments where the product is used, variations in how long-term use affects certain product characteristics, and so on. The difficulty of obtaining optimum design solutions is thus compounded by the need to carry out specific optimizations that provide sufficient robustness to safely accommodate anticipated ranges of variations. This paper expands the hierarchical multiobjective optimization method based on simplification and decomposition of characteristics so that optimizations can be concurrently conducted for both performance characteristics and maximization of robustness against characteristic variances. A principal cause of variations in performance characteristics is variations in the contact conditions of joints, and the utility of the proposed robust product design optimization method is demonstrated by applying it to machine-tool models that include joints. INTRODUCTION In today&apos;s product manufacturing environment, a wide range of factors such as product performances (such as the speed, accuracy and efficiency in accomplishing certain tasks), product qualities (such as performance variance and robustness) and operational and manufacturing costs must be considered when designing and producing machine products. To create successful products, numerous product characteristics need to be concurrently evaluated so that the specific requirements need to satisfy the product performances and qualities can all be satisfied to the highest possible degree. To accomplish these tasks, appropriate system optimization methods must be constructed and then used effectively. There are two main obstacles to achieving sophisticated system optimization results for product designs. One pertains to the problem of obtaining suitable optimum design solutions, and the other to whether or not the obtained solutions have sufficient robustness and can successfully accommodate the variations in design variables and parameters that will occur during product manufacturing and later usage of the product. These two problems are of equal importance in product design optimizations, since insufficient robustness can ultimately spoil what might be considered a superior design in situations where the need for adequate robustness is not adequately recognized

The lost girl ニオケル Alvina ノ タンキュウ ノ イミ

別冊, 太田藤一郎先生追悼号論文application/pdfdepartmental bulletin pape