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Epigenetics is the study of heritable changes in gene expression that do not involve changes to the DNA sequence, and DNA methylation is one of the epigenetic modifications. Technologies make it po...

The composition dependence of gravitational constant $G$ is measured at the millimeter scale to test the weak equivalence principle, which may be violated at short range through new Yukawa interactions such as the dilaton exchange force. A torsion balance on a turning table with two identical tungsten targets surrounded by two different attractor materials (copper and aluminum) is used to measure gravitational torque by means of digital measurements of a position sensor. Values of the ratios $\tilde{G}_{Al-W}/\tilde{G}_{Cu-W} -1$ and $\tilde{G}_{Cu-W}/G_{N} -1$ were $(0.9 \pm 1.1_{\mathrm{sta}} \pm 4.8_{\mathrm{sys}}) \times 10^{-2}$ and $ (0.2 \pm 0.9_{\mathrm{sta}} \pm 2.1_{\mathrm{sys}}) \times 10^{-2}$ , respectively; these were obtained at a center to center separation of 1.7 cm and surface to surface separation of 4.5 mm between target and attractor, which is consistent with the universality of $G$. A weak equivalence principle (WEP) violation parameter of $\eta_{Al-Cu}(r\sim 1\: \mathrm{cm})=(0.9 \pm 1.1_{\mathrm{sta}} \pm 4.9_{\mathrm{sys}}) \times 10^{-2} $ at the shortest range of around 1 cm was also obtained., Comment: submitted to Class. Quantum Grav

The MTV experiment (Mott Polarimetry for T-Violation Experiment) is running from 2009 at TRIUMF, which aims to search a large non-standard T-Violation in polarized nuclear beta decay. Existence of transverse polarization of electrons emitted from polarized 8Li nuclei, which are produced at TRIUMF-ISAC and stopped inside an aluminum stopper, is investigated. We utilize a Mott polarimeter consists of a planer drift chamber, measuring backward scattering left-right asymmetry from a thin lead analyzer foil. In this paper, preliminary results from the first physics run performed in 2010 are described.

The MTV (Mott Polarimetry for T-Violation Experiment) experiment at TRIUMF-ISAC (Isotope Separator and ACcelerator), which aims to achieve the highest precision test of time reversal symmetry in polarized nuclear beta decay by measuring a triple correlation (R-correlation), is motivated by the search for a new physics beyond the Standard Model. In this experiment, the existence of non-zero transverse electron polarization is examined utilizing the analyzing power of Mott scattering from a thin metal foil. Backward scattering electron tracks are measured using a multi-wire drift chamber for the first time. The MTV experiment was commissioned at ISAC in 2009 using an 80%polarized 8Li beam at 107 pps, resulting in 0.1%statistical precision on the R-parameter in the first physics run performed in 2010. Next generation cylindrical drift chamber (CDC) is now being installed for the future run.

Finding associated factors with childhood behavioural problems as early as preschool age is important. Studies have revealed several factors including socioeconomic factors, which may vary among different cultural background and population. However, investigation in general Japanese population of preschool age has not been well demonstrated. Thus, the objective of this study was to examine associated factors of childhood behavioural problems using Strengths and Difficulties Questionnaire (SDQ) in a prospective birth cohort study.Total 3813 SDQ were distributed between October 2014 and December 2015 to the subpopulation of prospective birth cohort study, the Hokkaido Study on Environment and Children's Health. The subpopulation consisted of participants who had reached age 5 and were born between April 2008 and December 2010. Baseline questionnaire filled at recruitment and birth record were used to obtain participant information. Children with total difficulties score ≧ 13 were defined as likelihood of behavioural problems. A total of 2553 children with valid answers were included into the analysis. The response rate was 67.1%.Number of children with likelihood of behavioural problems was 521 (20.4%). Boys showed more problematic scores than girls. Multivariate analysis found that maternal pre-pregnancy BMI ≧ 30 kg/mThis study found that prenatal socioeconomic factors were associated with likelihood of child behavioural problems at preschool age in Japan.

Summary The knowledge on the dose-response relationships between cumulative phthalate exposure and reproductive hormones in human are lacking. To assess the characteristics of the associations between hazard index (HI) of cumulative di-n-butylphthalate (DBP) and di-2-ethylhexylphthalate (DEHP) exposures and serum concentrations of free testosterone (fT), estradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), we used restricted cubic spline function to characterize the dose-response curves between the HI values and reproductive hormones for 74 male workers occupationally exposed to high levels of DBP and DEHP, and 63 male construction workers as comparison group matched for age and smoking status. The median of HI value was 5.30 for exposed workers, 53.0-fold that of unexposed workers (0.10). 89.2% of exposed workers and 1.6% of unexposed workers have HI over 1.00. We observed a borderline significantly negative association between HI and fT in exposed workers (r = −0.195, p = 0.096), but not in unexposed workers. The exposed workers showed inverted long-tailed J-shaped fT and FSH curves, and small changes in the LH curve, whereas unexposed workers had inverted and flattened-S-shaped fT and mirror-S-shaped LH and FSH curves. Both T production and hypothalamo-pituitary-testis (HPT) axis function were damaged in workers with high HI of phthalate exposures. HPT feedback function was activated in workers with both high and low HI, and plays an important role in preventing fT level from further decreasing with a rise in HI.

Author, This study investigated the possible relationships between exposures to mite allergen and airborne fungi with sick building syndrome (SBS) symptoms for residents living in newly built dwellings. We randomly sampled 5709 newly built dwellings in six prefectures from northern to southern Japan. A total of 1479 residents in 425 households participated in the study by completing questionnaire surveys and agreeing to environmental monitoring for mite allergen (Der 1), airborne fungi, aldehydes, and volatile organic compounds. Stepwise logistic regression analyses adjusted for confounders were used to obtain odds ratios (OR) of mite allergen and fungi for SBS symptoms. Der 1 had a significantly high OR for nose symptoms. Rhodotorula had a significantly high OR for any symptoms, and Aspergillus had significantly high OR for eye symptoms. However, the total colony-forming units had a significantly low OR for throat and respiratory symptoms. Eurotium had a significantly low OR for skin symptoms. In conclusion, dust-mite allergen levels and indoor airborne Rhodotorula and Aspergillus concentrations may result in SBS symptoms in newly built dwellings. PRACTICAL IMPLICATIONS: Various factors can cause sick building syndrome symptoms. This study focused on biologic factors such as dust-mite allergen and airborne fungi in newly built dwellings in Japan. Dust-mite allergen levels were significantly associated with higher rates of nose symptoms, airborne Rhodotorula concentrations were significantly associated with higher rates of any symptoms, and Aspergillus concentrations were significantly associated with higher rates of eye symptoms. Measures should be taken to reduce mite allergen levels and fungal concentrations in these dwellings.

The mechanism of strain rate dependence on the Bauschinger effect in dualphase type high strength steel sheets is investigated and the influence of mesostructure differences on spring-back is estimated in this study. Compression-tensile tests at a strain rate from 0.007/s to 100/s is conducted. To differentiate between the multiphase structure-induced effect and the matrix properties, the same tests are also conducted for ferrite single phase steel. As a result, the Bauschinger effect on dual phase steel is not associated with the matrix properties independently. Moreover, it is revealed that a multiphase structure-induced effect acts a dominant function for deformation characteristics through experiments and micro observations.

Motivated by a search for a new physics beyond the standard model, the MTV experiment (Mott Polarimetry for T-Violation Experiment) is intended to achieve the highest precision test of time-reversal symmetry in polarized nuclear beta decay by measuring a triple correlation (the R -correlation). The first physics run of the MTV experiment was performed in 2010 at TRIUMF-ISAC. This paper gives preliminary results and describes the next generation setup, which involves a cylindrical drift chamber.

Electron emission spectra obtained by thermal collisions of He*(2 3S) metastable atoms with CO on Ni(100) in the c(2×2) structure and on Ni(111) in the c(4×2) structure were measured to probe directly the spatial electron distribution. For a systematic comparison, the metastable spectra of free CO, condensed CO on Ni(111), and gaseous Cr(CO)6 were also measured under the same beam conditions. Our data showed that the relative ionization cross sections for the CO 4σ-, 1π-, and 5σ-derived states depend drastically on the molecular orientation of CO with respect to the metastable beam, reflecting the local electron density of CO in the impact region. Moreover, it was found that the 4σ- and 5σ- derived states of CO at hollow sites on Ni(111) are strongly modified in space by mixing with each other, where considerable charge transfer occurs from the C site to the O site in the 5σ-derived state and in the opposite way in the 4σ-derived state. In contrast, such a strong charge redistribution was not seen in the ...

The knowledge on the dose-response relationships between cumulative phthalate exposure and reproductive hormones in human are lacking. To assess the characteristics of the associations between hazard index (HI) of cumulative di-n-butylphthalate (DBP) and di-2-ethylhexylphthalate (DEHP) exposures and serum concentrations of free testosterone (fT), estradiol, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), we used restricted cubic spline function to characterize the dose-response curves between the HI values and reproductive hormones for 74 male workers occupationally exposed to high levels of DBP and DEHP, and 63 male construction workers as comparison group matched for age and smoking status. The median of HI value was 5.30 for exposed workers, 53.0-fold that of unexposed workers (0.10). 89.2% of exposed workers and 1.6% of unexposed workers have HI over 1.00. We observed a borderline significantly negative association between HI and fT in exposed workers (r=-0.195, p=0.096), but not in unexposed workers. The exposed workers showed inverted long-tailed J-shaped fT and FSH curves, and small changes in the LH curve, whereas unexposed workers had inverted and flattened-S-shaped fT and mirror-S-shaped LH and FSH curves. Both T production and hypothalamo-pituitary-testis (HPT) axis function were damaged in workers with high HI of phthalate exposures. HPT feedback function was activated in workers with both high and low HI, and plays an important role in preventing fT level from further decreasing with a rise in HI.

Montelukast, a cysteinyl leukotriene receptor 1 antagonist, is safe and efficacious in patients with asthma. The mechanisms underlying the significant interpatient variability in response to montelukast are not clear but are believed to be, in part, because of genetic variability.To examine the associations between polymorphisms in candidate genes in the leukotriene pathway and outcomes in patients with asthma on montelukast for 4-8 weeks, we evaluated the changes in peak expiratory flow (PEF), forced expiratory volume in 1 s (FEV(1·0) ) and patients' subjective symptom before and after montelukast treatment. DNA was collected from 252 Japanese participants.Two single-nucleotide polymorphisms (SNPs) in the ALOX5 (rs2115819) and LTA4H (rs2660845) genes were successfully typed. There was no difference between members of the general population (n = 200) and patients (n = 52) in each genotype frequency. Significant associations were found between SNP genotypes in the LTA4H gene and changes in PEF and FEV(1·0) . The PEF and FEV(1·0) responses to montelukast in the A/A genotypes (n = 4) for the LTA4H SNP were significantly higher than those in the G allele carriers (A/G+G/G) (n = 17).Despite the small sample size, our results suggest that genetic variation in leukotriene pathway candidate genes contributes to variability in clinical responses to montelukast in Japanese patients with asthma.

Aqueous solution of poly(vinyl methyl ether) (PVME) shows phase transition around 38°C. PVME hydrogel cross-linked by γ-ray irradiation is also a thermally responsive hydrogel and undergoes volume change at the same temperature; it swells below and shrinks above 38°C. PVME hydrogel prepared near phase transition temperature has heterogeneous and macroporous structure. The volume change of the macroporous hydrogel takes place rapidly with changing temperature. An attempt has been made to develop thermally activated chemomechamcal devices such as an artificial muscle model, an automatic separation system, an artificial finger model, and a photo-responsive device.

When a water-swollen polyelectrolyte gel is interposed between a pair of electrodes and DC current is applied, the gel undergoes electro-chemomechanical contraction and concomitant water exudation both in water and in the air. In order to clarify the mechanism of the phenomenon, contractile experiments were carried out under various conditions and led to the conclusion that the contraction is essentially associated with electrically driven movement of hydrated micro- and macroions in the gel (electrokinetic process).

A case-control study to determine the risk factors for human alveolar echinococcosis (AE) was conducted in Hokkaido, Japan. The 134 cases were either patients clinically diagnosed as having AE (N =61) or other individuals found to be seropositive for Echinococcus multilocularis although showing no abnormalities in ultrasound scans (N = 73). Two groups of case-matched controls were employed: one of 670 individuals selected from a list of residents of Hokkaido (group A) and the other of 650 subjects selected from a list of individuals who had been found seronegative in earlier investigations (group B). Because of the long latency of AE, potential risk factors were studied over two different periods: for the 0-10 and 11-20 years before the year of diagnosis/recorded seropositivity. The results of multivariate analyses, in which the cases were compared with each control group, indicated that the rearing of cattle and pigs and the use of well water were significant risk factors and that the use of tap water significantly decreased the risk of an individual having AE. Extension of the piped water supply and health education on improving the disposal of household rubbish (to keep foxes away from houses) should help reduce the risk of AE infection in the study area.

Introduction Cervical Cancer (CC) caused by oncogenic Human Papillomavirus (HPV) is the most common cancer in young Japanese women. Vaccination against HPV offers a primary prevention strategy. This study investigates knowledge of and attitudes towards CC and HPV vaccine in Japanese mothers. Methods Mothers (n=2192) with daughters aged 10–14 yrs were recruited from five elementary and 14 junior high schools in Sapporo city. After ethical approval, an anonymous questionnaire was distributed in schools and returned to the main investigator by post between July and September 2010. Results In total 876 questionnaires (40%) were returned and 862 used for analysis. Median age was 42 yrs. A total of 61.6% of mothers had undergone recent CC screening and 12.3% had experienced abnormalities. If vaccination were free 92.6% of mothers would vaccinate, but this decreased to 4.3% if the cost was >40 000 yen. While 52% of mothers knew of HPV, only 6.4% knew it caused CC. While, 73.1% thought their daughter was at risk of HPV infection, 72.5% also believed their daughter may die from it. While 85.7% wanted more information, 67.6% said they would use the Internet. Only 9.8% would ask a doctor. Factors significantly associated with vaccination intent were recent screening (OR=1.6, 95% CI 1.0 to 2.7), >13 yrs education (OR=1.4, 95% CI 1.0 to 2.3), believing vaccines prevented disease (OR=15.1, 95% CI 6.3 to 36.5) and no concerns about childhood vaccine safety (OR=3.8, 95% CI 1.9 to 7.9). Abnormal smears were not significant. Conclusion Knowledge of HPV is poor. However, high HPV vaccination coverage may be possible if appropriate funding and education are provided.

This paper reviews evidence concerning the relationship of social support and networks to psychological well-being in elderly people. Although few studies have used comparative concepts and featured measurements of social networks and social support, the overall findings are that depressive symptoms in elderly people are associated with (a) smaller size of social networks which are supportive, (b) lower emotional support which is anticipated or received, (c) lower instrumental support which is anticipated, and (d) not providing support to others, and that depressive symptoms are greater when the amount of received instrumental support is larger. There is evidence consistent with both direct effects of social networks and support on reducing depressive symptoms, and buffering effects to protect persons from adverse effects of stressful life events. In addition, physical health status, activities of daily living, income, and marital status are associated with depression among the elderly. A well-conducted longitudinal study is essential for research in this area in Japan.

According to a large extra dimension model, a deviation from Newton's inverse square law is expected at below sub-millimeter range. We have developed an experimental set up using a torsion balance pendulum and an online digital-image analysis system, aiming to test the Newtonian inverse square law at below millimeter scale. In addition, composition dependence of gravitational constant G is also tested at a millimeter scale, motivated to test the weak equivalence principle. In this paper, current status and results are described.

To analyze the different features of health status, social support and networks of elderly people by age groups, a survey was performed of the social environment and health related issues among residents aged 69-74 and 75-80, the so called old-old, in Takasu, a small farming town in Hokkaido. The results were as follows: 1. The percentage of elderly having some of the symptoms related to dementia, lower scores of ADL, and poorer conditions of eye sight or hearing were significantly higher among the elderly aged 75-80 compared to those aged 69-74. The prevalence of diseases, such as senile cataracts in both sexes, and heart diseases in men were also higher among those aged 75 and over. 2. Although there were no differences in the mean number of hospital admissions or in the percentage of those having been sick in bed for more than 1 week during the previous one year, both the mean number of out-patient visits and percentage having a family physician were significantly higher in the elderly over 75 than under. Deterioration of IADL were prominent in the item on being able to go far away by themselves. 3. Almost 70% of the elderly participated in community-based social activities in Takasu. There were only small differences in social support and network among the different categories of family structure of the elderly. However women over 75 had statistically significantly lower number of the social supports compared to the younger age groups. A significantly smaller percentage of people was able to obtain the emotional or care support from their spouse for in elderly over 75 than for elderly under 75. 4. The results of this study suggest the need to provide more social support and networks for the old-old over 75 years old who tend to have more diseases and to be in poorer health condition, both physically or mentally than younger old.

The purpose of this study was to investigate the relation between nerve conduction velocity (NCV) and some factors which affect the measurement, such as age, skin temperature, body build and alcohol consumption. Neurophysiological parameters of healthy volunteers (28 males and 27 females, aged 20-57 years) who were free from occupational exposure inducing neuropathy were determined by monitoring skin temperature. A questionnaire survey on height, alcohol and tobacco consumption was also performed. The following results were obtained: 1) Analysis of covariance to examine the relation between age groups and NCVs adjusting for skin temperature showed significant differences only in peroneal motor distal latency (MDL) and duration of sural sensory nerve action potential (SNAP) between age groups. However, there was no constant relation between these parameters and age. Multiple regression analysis showed the significant relationships between age and ulnar MDL and the duration of sural sensory nerve action potential, adjusting for sex, height, weight, BMI, alcohol intake (frequency/week, ethanol equivalent ml/week), tobacco consumption (/day), skin temperature and education years. 2) The skin temperature had significant effects on ulnar MDL, ulnar sensory NCV, duration of ulnar SNAP, sural sensory NCV and amplitude and duration of sural SNAP according to the results of multiple regression analysis and analysis of variance. 3) The body mass index had an independent effect on the ulnar nerve conduction, shortening MDL and the duration of the sensory nerve action potential. 4) Consumption of alcohol and tobacco had no significant relation to nerve conduction velocity in our study. These results show that skin temperature is a major covariate of peripheral nerve conduction and that it is very important to control skin temperature in studies on nerve conduction measurements.

To determine the risk factors for echinococcus infection, we conducted a case-control study in the Nemuro region of Hokkaido Prefecture. The cases included both clinically diagnosed patients with echinococcosis and registered persons who were seropositive. The control group was matched by residence, age (+/- 5 years) and sex. The data on the 99 cases and 430 controls were collected by mailed questionnaire. Because of the long latency of echinococcosis, we investigated the potential risk factors over two different periods-from 11-20 years before the time of registration, and from 10 years before the registration to the time of registration. For the 11-20 years before registration period, using well water as drinking water and cattle raising significantly increased the risk of echinococcosis. In the period 10 years before registration to the time of registration, hog raising also increased the risk. In contrast, drinking tap water decreased the risk. These results suggest the importance of a screening program, especially targeting people engaged in dairy farming and hog raising, as well as the need for extension of tap water services and health education on refuse disposal.

A population-based comparative study was performed on public awareness and knowledge about the risk of Echinococcosis and the life habits of the people living in 2 towns in eastern Hokkaido, Bekkai and akan. Bekkai has had an anti-echinococcosis policy and Akan has only limited experiences with such countermeasures. The results of the survey were as follows: 1) Compared with the inhabitants in the town of Akan, the residents in Bekkai had significantly higher correct response rates for many questions concerning parasitological knowledge and the risks of echinococcosis, and knew about subjects such as the pathogen, latency period, susceptible organs, the prognosis, the possibility of transmission of echinococcosis from human to human and methods for the sterilization of eggs from infected animals. 2) The rate of correct answers to such questions were approximately 70 to 90% in both towns. However the percentage of correct answers to questions about carrier animals and the question of human susceptibility were relatively low, ie., 45% and 20%, respectively, even in Bekkai. 3) The residents of Akan knew more about carrier animals of echinococcosis than the inhabitants of Bekkai. In Akan woman and persons in their 20's and 30's had lower rates of correct answers. Further health education should be aimed toward such people. 4) Foxes appeared near private homes more frequently in Akan than in Bekkai. More inhabitants of Akan used spring water as drinking water than in Bekkai, while more inhabitants used tap water as drinking water in Bekkai. Only a few inhabitants paid attention to how to prepare vegetables for cooking. This information suggests that echinococcosis may spread in Akan in the near future. 5) Our results suggest that better organized health education programs, the extension of tap water services in Akan, and the establishment of proper methods for disposal of garbage and the afterbirth of cattle are necessary to reduce the presence of foxes in inhabited areas.

We previously studied the fatigue and stress of anesthesiologists at work using a flicker photometer, visual reaction time test, questionnaires, and Holter EKG. In the present study, we investigated the fatigue and stress in seven junior anesthesiologists at work using a flicker photometer and a stabilo-meter. The stabilo-meter measures postural stabilization. We performed each test three times on each subject for a total of twenty-one times. The flicker test and the stabilo-test showed the increase in fatigue in 17 (18%) and in 16 tests (76%), respectively, in all seven subjects. Increase of fatigue in both the flicker and stabilo-tests was observed in 13 tests (61%) of 6 subjects. There was a good relationship between the flicker test and the stabilo-test. Therefore, the stabilo-test appears to be a useful method for investigating the fatigue of anesthesiologists.

In order to analyze the different features of the social network, social support system and health status of elderly people, a survey was performed of the social environment and health related issues among 70 year-old men and women in Sapporo, a large city, and Yubari, a small city which has experienced coal mine closures, both in Hokkaido prefecture. The results were as follows: 1. In Yubari, the health status of the elderly living alone was better than those with other familial categories such as living with their spouse, or with the families of their children. In contrast, the status of the elderly living alone in Sapporo was worse than the others. The mean numbers of out-patient visits and hospital admissions during the previous one year were higher among elderly people living alone in both areas. 2. There were large differences in social support and social network in the two areas and among the living status of the elderly. In particular, persons living alone in Sapporo had statistically significantly lower amount of support than others. Elderly people in Sapporo had fewer contacts with their neighbors and only a small number of them participated in community-based social associations compared with the same age groups in the city of Yubari. 3. An extremely small number of the elderly were provided formal support from official personnel such as public health nurses, district welfare commissioners and so on. The results of this study suggest the need for more formal and informal networks to provide for social support for those elderly men and women living alone in large cities.

A new experimental project called MTV(Mott Polarimetry for T-Violation Experiment)-S1183 has started at TRIUMF, aiming to achieve the highest precision test of time reversal symmetry in polarized nuclear beta decay. In this experiment, existence of T-violating transverse polarization of electrons emitted from polarized nuclei is examined, using a multi-wire drift chamber (MWDC) as an electron tracking detector in order to measure Mott scattering asymmetries. In this paper, technical aspects of the electron polarimetry are described. The Mott polarimeter, MWDC, consists of six sense layers. In order to improve the real backward scattering event purity, a new intelligent triggering system using FPGA module to perform on-line hit pattern recognition was developed. The new triggering system was installed for the first commissioning experiment in November 2009 at TRIUMF-ISAC. In addition to the triggering system, a new buffering DAQ system was also developed in order to achieve the needed high triggering rate at ISAC. Details of their performance are also described.

A new experimental project called MTV (Mott Polarimetry for T-Violation Experiment), is running at TRIUMF. It aims to achieve the highest precision test of time reversal symmetry in polarized nuclear beta decay by measuring a triple correlation (R-correlation), motivated to search a new physics beyond the standard model. It is because the CKM predicts negligible effects on the u-d quark system. In this experiment, the existence of non-zero transverse electron polarization is examined utilizing the analyzing power of Mott scattering from a thin metal foil. Backward scattering electron tracks are measured using a multi-wire drift chamber event-by-event for the first time. The tracking device eliminates the largest systematic effect, which has been limiting the sensitivity of previous studies. The MTV experiment was commissioned at TRIUMF-ISAC in 2009 using an 80% polarized 8Li beam at 10 Mpps resulting in 3.6% precision on the R-parameter, after performing a feasibility test at KEK-TRIAC in 2008 using an 8% polarized beam at 100 kpps yielding 41% statistical precision. In 2010, a physics production run is scheduled, aiming to reach below 0.1% precision. In this document, the preparation status for the 2010 run and results from the commissioning run are described.

In order to determine if there are any residual effects of long-term exposure to mercury vapor, neurobehavioral tests were given to ex-mercury miners about 18 years after the cessation of mercury exposure. Seventy-six male ex-mercury miners who had been exposed to relatively high concentrations of mercury vapor (over 1.0 mg/m3) and with a past history of mercury intoxication were compared to age (+/- 3 years)-, sex-, and years of education-matched controls. Although the extent of the workers' symptoms caused by mercury poisoning, termed erethismus merculialis, markedly decreased after the cessation of exposure, the prevalence of neurological symptoms (such as hand tremors, headaches, and slurred speech) and symptoms of senility (such as low-back pain, loss of sexual desire) in the ex-miners was significantly higher than those in the controls. Matched-pair analysis showed that performances of motor coordination, Simple reaction time, and Short-term memory in the ex-miners were significantly deteriorated compared to those of controls. There are slight but persistent effects on neurobehavioral function, especially on motor coordination function, among mercury miners more than 10 years after the cessation of exposure.

We studied the fatigue and stress of anesthesiologists at work using a flicker photometer, visual reaction time test and questionnaires to them. The two kinds of visual apparatus enabled us to measure two types of fatigue. On the other hand, the questionnaires relating to fatigue and stress indicated the stress tendencies and stressors by age, anesthetic experience, and sex. The results suggest that these methods are useful for measuring the fatigue and stress of anesthesiologists.

1553 Background: It is well known that estrogen contained in contraceptive pills has a relationship with the incidence of hormone-dependent cancers. Conversely, there appears to be very little discussion concerning dietary estrogen from meat in relation to cancer incidence despite the fact that beef and chicken of most daily diets comes from animals fed with estrogen supplements. Thus, we evaluated estrogen concentrations in meat. Methods: Intra-tissue concentrations of Estradiol 17 Beta (E2) and Estrone (E1) were measured in beef (produced in USA, Japan: n = 40, 40) and chicken (produced in USA, Japan, Brazil: n = 25, 25, 25) by LC-MS/MS. Fat and red meat were examined separately in each meat. As a control we also analyzed fat tissues of postmenopausal Japanese women (n = 25). Results: Estrogen levels were generally higher in fat than in red meat. Median concentrations (pg/g) in Japanese chicken fat (E2 = 21.1, E1 = 65.7) and in USA chicken fat (20.7, 54.6) were the highest, and USA beef fat (14.0, 7.7) ...

Micropumps using polymer gel actuators are proposed and two prototypes developed are described. One is actuated by a highly water absorbing polymer gel, while the other is actuated by a thermoresponsive polymer gel. The first type, the micro-capsule pump using the highly water absorbing polymer gel, consists structurally of an inlet with a semipermeable membrane, an outlet with a one-way valve, and a storage tank controlled by the water absorbing polymer gel. The gel rests within a thin film, and the semipermeable membrane is located on the inlet side. The important feature of this actuator is that an external driving power supply is not required in this micropump. The second type, the micropump using the thermoresponsive polymer gel, has two one-way valves which make use of the highly water absorbing polymer gel as a blocking ball. The polymer gel actuator used is constituted of polyvinyl methyl ether (PVME) atatic polymer gel. Repeating the heating and cooling processes causes, the PVME to repeat its shrinking and swelling motions. The micropump was tested on switching heating by a nichrome wire with electric current. >

Symptoms as an important sign of the effects of methyl bromide were studied in 56 male workers (37 currently exposed and 19 previously exposed) in a methyl bromide factory. The workers were 18 to 62 yr of age (mean age: 41) and were exposed from 1 to 25 yr (mean: 7 yr). They were compared to 56 age-matched referents with a standardized questionnaire. The results of pairwise comparison of the symptoms of the age-matched pairs of exposed and referent subjects showed that the occurrence of dizziness, numbness, paresthesia and weakness of extremities, nightmares, fatigue and dry and scaly skin was statistically significantly higher among the workers than among the referents. When the symptoms during the work shift (acute symptoms) were compared, irritation symptoms such as itching, bullae or reddish swollen hands and runny noses with nasal irritation were reported significantly more often in the exposed groups. The correlation of the symptoms among the exposed workers suggested that chronic symptoms are closely related to acute irritation symptoms and exposure duration. The results suggest that symptom inquiry is useful for detecting the possible effects of exposure to methyl bromide.

System which undergoes shape change and develop contractile force responsing to outside stimulus is called “Chemomechanical (or Mechanochemical) System” 1) and refers to thermodynamic systems capable of transforming chemical energy directly into mechanical work or conversely of transforming mechanical into chemical potential energy2). The isothermal conversion of chemical energy into mechanical work underlies the motility of all living organisms and can easily be seen, for instance, in muscle, flagella and ciliary movement. All these biological systems are characterized by an extremely high efficiency of energy conversion. The high efficiency of the biological systems is largely due to direct conversion of chemical energy without unnecessary intermediate passes producing heat.