This paper describes a theoretical estimation of the geometry of negative epoxy-resist microneedles prepared via inclined/rotated ultraviolet(UV)lithography based on spatially controlled UV exposure doses.In compariso...This paper describes a theoretical estimation of the geometry of negative epoxy-resist microneedles prepared via inclined/rotated ultraviolet(UV)lithography based on spatially controlled UV exposure doses.In comparison with other methods based on UV lithography,the present method can create microneedle structures with high scalability.When negative photoresist is exposed to inclined/rotated UV through circular mask patterns,a three-dimensional,needle-shaped distribution of the exposure dose forms in the irradiated region.Controlling the inclination angles and the exposure dose modifies the photo-polymerized portion of the photoresist,thus allowing the variation of the heights and contours of microneedles formed by using the same mask patterns.In an experimental study,the dimensions of the fabricated needles agreed well with the theoretical predictions for varying inclination angles and exposure doses.These results demonstrate that our theoretical approach can provide a simple route for fabricating microneedles with on-demand geometry.The fabricated microneedles can be used as solid microneedles or as a mold master for dissolving microneedles,thus simplifying the microneedle fabrication process.We envision that this method can improve fabrication accuracy and reduce fabrication cost and time,thereby facilitating the practical applications of microneedle-based drug delivery technology.展开更多
Ⅰ. INTRODUCTION Many investigations have been made on stress response caused by noise, but most of them were concerned with instantaneous or temporary effects of noise. Very few investigated the effects of occupation...Ⅰ. INTRODUCTION Many investigations have been made on stress response caused by noise, but most of them were concerned with instantaneous or temporary effects of noise. Very few investigated the effects of occupational noise exposure on human stress response over a long period of time. For verifying this we did an analysis of the cortisol/cGMP ratios and the total amounts of cAMP+cGMP of the groups exposed to noise of different intensities.展开更多
Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed ...Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed to radiation as a result of two radiation accidents in the South Urals.Methods A layer-by-layer morphological study of the lens of 1,377 exposed individuals was conducted according to a special program in the Clinical Department of the Urals Research Center for Radiation Medicine(URCRM)68 years after the onset of exposure.Lens changes were classified in accordance with the lens opacities classification(LOCS)III and included images of lens.To calculate the doses to lens,the data were taken into account,including the person's residence history in the radioactively contaminated territory,age and sex that affected their lifestyle and diet,radionuclide distribution in organs and tissues.Individualized lens doses were calculated using Techa River Dosimetry System(TRDS)-2016.Case-control method was used for statistical analysis.Results Individual values of absorbed dose to lens ranged from 0 to 600mGy.A dose-dependent increased risk of posterior subcapsular cataract(PSC)(OR1.54,95%CI:1.04–2.27)and nuclear cataract(OR1.84,95%CI:1.14–2.95)was found among chronically exposed individuals by a case-control method.No evidence of dose effect was found for cortical cataracts.Conclusions The results showed that population exposed to long-term chronic low-dose radiation was subjected to an increased risk of PSC and nuclear cataract development.展开更多
Objectives The purposes were to determine the relationship between silicosis among foundry workers and their cumulative exposure to silica dust, and to establish a regression model to predict the risk for developing s...Objectives The purposes were to determine the relationship between silicosis among foundry workers and their cumulative exposure to silica dust, and to establish a regression model to predict the risk for developing silicosis by a given length of employment and air concentrations of silica at worksites. Methods A 29-year cohort study was conducted, including all those employed for more than one year during January 1, 1980 to December 31, 1996 and all members of the cohort were followed-up to December 3 1, 2008. In total, 2 009 workers of an automobile foundry in Shiyan, Hubei province were recruited in the study, 1 300 at eight worksites including sand preparation, cast shakeout, and finishing, melting, moulding, core-making, overhead crane operation and pouring as exposed group, and the other 709 auxiliary workers at the same factory, such as electricians, inspectors, fitters, and so on, as control group. Person-years of observation were calculated by persons observed and years followed-up for each of them. Person-year incidence of silicosis and its relative risk （RR） or odds ratio （OR） and 95% confidence intervals （CI） among the workers were estimated, adjusted for relevant factors with logistic regression model using SPSS version 15.0 software. Results Totally, 2 009 workers were followed-up for 37 151 person-years and 48 cases of silicosis were found, with an overall incidence of 1.34 per thousand, 2.02 per thousand in exposed group, and 0.15 per thousand in control one. Risk of silicosis was significantly higher in the exposed group than that in the control one （RR=13.13, 95% CI 3.18-54.13）, higher in men than that in women （RR=13.92, 95% CI 1.92-100.93）. Risks of silicosis varied by job, highest in those exposed to cast shakeout and finishing （RR=28.14, 95% CI 6.43-123.11）, followed by those exposed to pouring （RR-22.23, 95% CI 5.01-98.55） in the foundry. Average length of employment at onset of silicosis was 25.94 years, and silicosis incidence increased with length of employmen展开更多
基金This work was partially supported by Japan Science Technology Agency,Izumi Science and Technology Foundation,the Tateisi Science and Technology Foundation,and the Mazda Foundation
文摘This paper describes a theoretical estimation of the geometry of negative epoxy-resist microneedles prepared via inclined/rotated ultraviolet(UV)lithography based on spatially controlled UV exposure doses.In comparison with other methods based on UV lithography,the present method can create microneedle structures with high scalability.When negative photoresist is exposed to inclined/rotated UV through circular mask patterns,a three-dimensional,needle-shaped distribution of the exposure dose forms in the irradiated region.Controlling the inclination angles and the exposure dose modifies the photo-polymerized portion of the photoresist,thus allowing the variation of the heights and contours of microneedles formed by using the same mask patterns.In an experimental study,the dimensions of the fabricated needles agreed well with the theoretical predictions for varying inclination angles and exposure doses.These results demonstrate that our theoretical approach can provide a simple route for fabricating microneedles with on-demand geometry.The fabricated microneedles can be used as solid microneedles or as a mold master for dissolving microneedles,thus simplifying the microneedle fabrication process.We envision that this method can improve fabrication accuracy and reduce fabrication cost and time,thereby facilitating the practical applications of microneedle-based drug delivery technology.
文摘Ⅰ. INTRODUCTION Many investigations have been made on stress response caused by noise, but most of them were concerned with instantaneous or temporary effects of noise. Very few investigated the effects of occupational noise exposure on human stress response over a long period of time. For verifying this we did an analysis of the cortisol/cGMP ratios and the total amounts of cAMP+cGMP of the groups exposed to noise of different intensities.
基金The performed studies have been supported by the Federal Medical Biological Agency.
文摘Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed to radiation as a result of two radiation accidents in the South Urals.Methods A layer-by-layer morphological study of the lens of 1,377 exposed individuals was conducted according to a special program in the Clinical Department of the Urals Research Center for Radiation Medicine(URCRM)68 years after the onset of exposure.Lens changes were classified in accordance with the lens opacities classification(LOCS)III and included images of lens.To calculate the doses to lens,the data were taken into account,including the person's residence history in the radioactively contaminated territory,age and sex that affected their lifestyle and diet,radionuclide distribution in organs and tissues.Individualized lens doses were calculated using Techa River Dosimetry System(TRDS)-2016.Case-control method was used for statistical analysis.Results Individual values of absorbed dose to lens ranged from 0 to 600mGy.A dose-dependent increased risk of posterior subcapsular cataract(PSC)(OR1.54,95%CI:1.04–2.27)and nuclear cataract(OR1.84,95%CI:1.14–2.95)was found among chronically exposed individuals by a case-control method.No evidence of dose effect was found for cortical cataracts.Conclusions The results showed that population exposed to long-term chronic low-dose radiation was subjected to an increased risk of PSC and nuclear cataract development.
文摘Objectives The purposes were to determine the relationship between silicosis among foundry workers and their cumulative exposure to silica dust, and to establish a regression model to predict the risk for developing silicosis by a given length of employment and air concentrations of silica at worksites. Methods A 29-year cohort study was conducted, including all those employed for more than one year during January 1, 1980 to December 31, 1996 and all members of the cohort were followed-up to December 3 1, 2008. In total, 2 009 workers of an automobile foundry in Shiyan, Hubei province were recruited in the study, 1 300 at eight worksites including sand preparation, cast shakeout, and finishing, melting, moulding, core-making, overhead crane operation and pouring as exposed group, and the other 709 auxiliary workers at the same factory, such as electricians, inspectors, fitters, and so on, as control group. Person-years of observation were calculated by persons observed and years followed-up for each of them. Person-year incidence of silicosis and its relative risk （RR） or odds ratio （OR） and 95% confidence intervals （CI） among the workers were estimated, adjusted for relevant factors with logistic regression model using SPSS version 15.0 software. Results Totally, 2 009 workers were followed-up for 37 151 person-years and 48 cases of silicosis were found, with an overall incidence of 1.34 per thousand, 2.02 per thousand in exposed group, and 0.15 per thousand in control one. Risk of silicosis was significantly higher in the exposed group than that in the control one （RR=13.13, 95% CI 3.18-54.13）, higher in men than that in women （RR=13.92, 95% CI 1.92-100.93）. Risks of silicosis varied by job, highest in those exposed to cast shakeout and finishing （RR=28.14, 95% CI 6.43-123.11）, followed by those exposed to pouring （RR-22.23, 95% CI 5.01-98.55） in the foundry. Average length of employment at onset of silicosis was 25.94 years, and silicosis incidence increased with length of employmen
