UV-B Transmittance Research Articles

Acclimation of Arabidopsis thaliana to low temperature protects against damage of photosystem II caused by exposure to UV-B radiation at 9 °C

Various environmental variables interact with UV-B radiation (280–315 nm), among them temperature. In many plants epidermal UV screening is induced by low temperature even in the absence of UV irradiation. On the other hand, low temperature can aggravate damage caused by UV-B radiation. We investigated the interaction of UV-B radiation and low temperature in Arabidopsis thaliana (L.) Heynh. Exposure of plants grown at moderate temperature (21 °C) to UV-B radiation at 9 °C resulted in significantly higher damage of photosystem II (PS II) as compared to exposure at 21 °C. The higher damage at low temperature was related to slower recovery of maximal PS II quantum efficiency at this temperature. Epidermal UV-B transmittance was measured using a method based on chlorophyll fluorescence measurements. Acclimation to low temperature enhanced epidermal UV-B screening and improved the UV-B resistance considerably. Differences in the apparent UV-B sensitivity of PS II between plants grown in moderate or acclimated to cool temperatures were strongly diminished when damage was related to the UV-B radiation reaching the mesophyll (UV-Bint) as calculated from incident UV-B irradiance and epidermal UV-B transmittance. Evidence is presented that the remaining differences in sensitivity are caused by an increased rate of repair in plants acclimated to 9 °C. The data suggest that enhanced epidermal UV-B screening at low temperature functions to compensate for slower repair of UV-B damage at these temperatures. It is proposed that the UV-B irradiance reaching the mesophyll should be considered as an important parameter in experiments on UV-B resistance of plants.

High impact of seasonal temperature changes on acclimation of photoprotection and radiation-induced damage in field grown Arabidopsis thaliana

At temperate latitudes environmental factors such as irradiance, including ultraviolet-B radiation (UV-B, 280–315 nm), temperature and day length vary widely over the course of a year in a concerted way. In the present study physiological acclimation of photoprotection, growth and development of the model organism Arabidopsis thaliana were correlated to these strongly but gradually changing conditions in a one year field study. Plants were sown in the field avoiding any manipulation (and abrupt change) during their life. Developmental rate was strongly dependent on prevailing temperature. Moderate signs of light stress in form of photoinhibition at photosystem II were significantly related to solar irradiances while amount of DNA damage was low and not correlated to UV-B irradiance. Although all the markers were hypothesized to primarily react to radiation, multiple regression analysis showed at least a similarly strong influence of temperature as that of light. Especially for the classical UV screening compounds a positive correlation to UV-B radiation during the course of the year was absent, whereas there was a significant negative correlation between temperature and quercetin content. The sum of violaxanthin cycle pigments was correlated to both, irradiance and temperature, but with opposite sign. Epidermal UV-B transmittance was also much better related to air temperature than to UV-B irradiance. The data show that under natural conditions temperature has at least a similar importance for photoprotective acclimation and partially also for photosensitivity as solar irradiance.

Contents of phenolics and carotenoids in tomato grown underpolytunnels with different UV-transmission rates

Tomato (Solanum lycopersicum L.) is among the economically most important vegetables in Europe, valued for its bioactive properties due to significant contents of vitamins, carotenoids, and phenolic compounds. In this study, the tomato cultivar Big Beef F1 was grown in the open field (OF) and under polytunnels in central Serbia during 3 years. Polytunnels were covered with two foils (both with 57% reduced photosynthetic active radiation, PAR) differing in UV-A and UV-B transmittance. The aim of our work was to determine the influence of light conditions on accumulation of phytonutrients (carotenoids and phenolics) in the peel and flesh of ripe tomato fruits. The amount of effective antioxidants, caffeic acid, and quercetin (phenolics with ortho-dihydroxy substitution) in the peel was the highest in tomato fruits grown in the OF (maximal PAR and UV-A and UV-B radiation). Moreover, the content of leaf epidermal flavonoids was the highest in the OF. The content of lycopene and β-carotene in the flesh of tomato fruit was higher under the polytunnel with higher UV-transmittance. Our results showed that selection of the right light conditions (quality and intensity) for tomato production has a significant effect on the accumulation of beneficial phenolics and carotenoids.

Environmental determinants of previtamin D synthesis in the United Arab Emirates.

ABSTRACTDespite abundant sunshine throughout the year, vitamin D deficiency is endemic in the UAE. Solar radiation within the UVB range of the spectrum is required for the photosynthesis of previtamin D3 in the skin. Atmospheric transmission of UVB is strongly influenced by atmospheric conditions and solar zenith angle. We investigated the effects of diurnal and seasonal variation on the availability of sufficient UVB radiation for adequate previtamin D3 synthesis using an established in vitro model. Borosilicate ampoules of 7-dehydrocholesterol, the precursor of previtamin D3, in ethanol (50 µg/mL) were exposed to direct sunlight in an urban area of Abu Dhabi, at one hourly intervals between 0800 and 1700, on one day of each month over a period of one year. Conversion to previtamin D3, vitamin D3 and metabolically inactive photoisomers was analyzed using high performance liquid chromatography. The efficiency of 7-dehydrocholesterol conversion to previtamin D3 varied estimated UVB intensity. At the latitude of Abu Dhabi (24.2 N) previtamin D3 synthesis can occur throughout the year. However very little if any previtamin D3 was produced before 0900 hrs.and after 1600 hrs. Local conditions in Abu Dhabi are likely sufficient to maintain vitamin D levels throughout the year given adequate sun exposure.

Incorporation of Rutin in Electrospun Pullulan/PVA Nanofibers for Novel UV-Resistant Properties.

This study aimed to investigate the incorporation of rutin into electrospun pullulan and poly(vinyl alcohol) (PVA) nanofibers to obtain ultraviolet (UV)-resistant properties. The effect of weight ratios between pullulan and PVA, and the addition of rutin on the nanofibers’ morphology and diameters were studied and characterized by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) analysis was utilized to investigate the interaction between pullulan and PVA, as well as with rutin. The results showed that the inclusion of PVA results in the increase in the fiber’s diameter. The addition of rutin had no obvious effect on the fibers’ average diameters when the content of rutin was less than 7.41%. FTIR results indicated that a hydrogen bond formed between pullulan and PVA, also between these polymers and rutin. Moreover, the addition of rutin could enhance the mechanical properties due to its stiff structure and could decrease the transmittance of UVA and UVB to be fewer than 5%; meanwhile, the value of ultraviolet protection factor (UPF) reached more than 40 and 50 when the content of rutin was 4.46% and 5.67%, respectively. Therefore, the electrospun pullulan/PVA/rutin nanofibrous mats showed excellent UV resistance and have potential applications in anti-ultraviolet packaging and dressing materials.

Transparent cellulose/polyhedral oligomeric silsesquioxane nanocomposites with enhanced UV-shielding properties

The solubility of eight types of polyhedral oligomeric silsesquioxane (POSS) derivatives in an ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl) and the dispersion of POSS in cellulose matrix were examined. Only a special POSS containing both aminophenyl and nitrophenyl groups (POSS-AN, NH2:NO2=2:6) was selected to prepare nanocomposites, because of its good solubility in AmimCl and high stability during the preparation process. POSS-AN nanoparticles were uniformly dispersed in a cellulose matrix with a size of 30–40nm, and so the resultant cellulose/POSS-AN nanocomposite films were transparent. The mechanical properties of the films achieved a maximum tensile strength of 190MPa after addition of 2wt% POSS-AN. Interestingly, all of the cellulose/POSS-AN films exhibited high UV-absorbing capability. For the 15wt% cellulose/POSS-AN film, the transmittance of UVA (315–400nm) and UVB (280–315nm) was only 9.1% and nearly 0, respectively. The UV aging and shielding experiments showed that the transparent cellulose/POSS-AN nanocomposite films possessed anti-UV aging and UV shielding properties.

할로겐과 카르복시산으로 치환된 피리딘 첨가제를 사용한 소프트 콘택트렌즈의 물성 평가

Purpose: This study evaluated the optical and physical and characteristics of soft contact lens polymerized with addition of 3-chloropyridine-4-carboxylic acid and 3-fluoropyridine-4-carboxylic acid in the basic hydrogel contact lens material. In particular, the utility of 3-chloropyridine-4-carboxylic acid and 3-fluoropyridine- 4-carboxylic acid as a hydrogel contact lens material was investigated. Methods: In this study, 3-chloropyridine-4-carboxylic acid and 3-fluoropyridine-4-carboxylic acid were used as additives. Also, 2-hydroxyethyl methacrylate, acrylic acid, methyl methacrylate and a cross-linker EGDMA were co-polymerized in the presence of AIBN as an initiator. Results: The physical properties of the produced polymers were measured as followings. The water content of 34.54~37.15%, refractive index of 1.4320~1.4342, tensile strength of 0.2872~0.3608 kgf and contact angle of , UV-B transmittance of 76.8~82.4% and UV-A transmittance of 84.6~86.6% were obtained respectively. Conclusions: Based on the results of this study, contact lens material containing 3-chloropyridine-4-carboxylic acid and 3-fluoropyridine-4-carboxylic acid is expected to be able to used as a material for high wettability and UV-block hydrogel contact lens.

Preparation and Characterization of Ophthalmic Lens Materials Containing Titanium Silicon Oxide and Silver Nanoparticles.

Hydrogel ophthalmic lenses containing fluorine-substituted aniline group, titanium silicon oxide nartoparticles, and silver nanoparticles were copolymerized, and the physical and optical properties of the hydrogel lenses were measured. To produce the hydrophilic ophthalmic lenses, the additives were added to the mixture containing HEMA, NVP, MA, EGDMA, and AIBN. The cast mold method was used for the manufacture of the hydrogel ophthalmic lenses, and the produced lenses were completely soaked in a 0.9% NaCl normal saline solution for 24 hours for hydration. The physical properties of the produced macromolecule showed that the water content was 32.5-37.6%, the refractive index was 1.450-1.464, the UV-B transmittance was 0.5-35.2%, and the contact angle was between 56 and 69°. Also, the addition of aniline, titanium silicon oxide, and silver nanoparticles allowed the ophthalmic lenses to block UV. These results show that the produced macromolecule can be used as hydrophilic lenses for ophthalmologic purposes that can block UV.

The risk of melanoma in pilots and cabin crew: UV measurements in flying airplanes.

Recently, a meta-analysis reported an increased incidence of melanoma in pilots and cabin crew, which was possibly due to occupational exposures.1 Cabin crews’ exposure to cosmic radiation was assessed in different studies and always found below the allowed dose limit.2 However, the cumulative exposure of pilots and cabin crew to UV radiation, a known risk factor for melanoma, has not been assessed to our knowledge. Airplane windshields are commonly made of polycarbonate plastic or multilayer composite glass. UV-B (280–320 nm) transmission through both plastic and glass windshields was reported to be less than 1%. However, UV-A (320–380 nm) transmission ranged from 0.41% to 53.5%, with plastic attenuating more UV radiation than glass.3 Intrigued by our findings and the clinical observation of pilots developing melanomas on sun-exposed skin, we measured the amount of UV radiation in airplane cockpits during flight and compared them with measurements performed in tanning beds.

Do UV-blocking Soft Contact Lenses Meet ANSI Z80.20 Criteria for UV Transmittance?

Purpose:To compare ultraviolet (UV) ray transmission in four UV-blocking soft contact lenses with Z80.20 standards set by the American National Standards Institute (ANSI).Methods:Four soft contact lenses including Acuvue Oasys (Johnson & Johnson, Ireland), Acuvue 2 (Johnson & Johnson, Ireland), Zeiss CONTACT Day 30 (Zeiss, Germany), and Sauflon 55 UV (Sauflon, UK) were evaluated for UV transmission. One-way ANOVA testing was performed to compare mean values of UVA and UVB transmission for the contact lenses.Results:Acuvue Oasys, Acuvue 2, Zeiss CONTACT Day 30 and Sauflon 55 UV showed UV-B transmittance values of 0.24%, 1.46%, 10.37%, and 2.52%, respectively. Corresponding values for UV-A transmittance were 20.81%, 33.49%, 44.03% and 42.53%, respectively. One-way ANOVA showed a statistically significant difference among the tested contact lenses in terms of UV-B (P < 0.001) and UV-A (P < 0.001) transmission.Conclusion:Acuvue Oasys met the ANSI criteria for UV transmission and may thus be a good choice for eye and vision care specialists and contact lens wearers seeking UV protection.

Light Conversion and Scattering in UV Protective Textiles

Abstract The primary cause of skin cancer is believed to be a long exposure to solar ultraviolet radiation (UV-R) crossed with the amount of skin pigmentation in the population. It is believed that in childhood and adolescence 80% of UV-R gets absorbed, whilst in the remaining 20% gets absorbed later in the lifetime. This suggests that proper and early photoprotection may reduce the risk of subsequent occurrence of skin cancer. Textile and clothing are the most suitable interface between environment and human body. It can show UV protection, but in most cases it does not provide full sun screening properties. UV protection ability highly depends on large number of factors such as type of fibre, fabric surface and construction, type and concentration of dyestuff, fluorescent whitening agent (FWA), UV-B protective agents, as well as nanoparticles, if applied. Based on electronically excited state by energy of UV-R (usually 340-370 nm), the molecules of FWAs show the phenomenon of fluorescence giving to white textiles high whiteness of outstanding brightness by reemitting the energy at the blue region (typically 420-470 nm) of the spectrum. By absorbing UV-A radiation, optical brightened fabrics transform this radiation into blue fluorescence, which leads to better UV protection. Natural zeolites are rock-forming, microporous silicate minerals. Applied as nanoparticles to textile surface, it scatters the UV-R resulting in lower UV-A and UV-B transmission. If applied with other UV absorbing agents, e.g. FWAs, synergistic effect occurs. Silicones are inert, synthetic compounds with a variety of forms and uses. It provides a unique soft touch, is very resistant to washing and improves the property of fabric to protect against UV radiation. Therefore, the UV protective properties of cotton fabric achieved by light conversion and scattering was researched in this paper. For that purpose, the stilbene-derived FWAs were applied on cotton fabric in wide concentration range without/with the addition of natural zeolite or silicone- polydimethylsiloxane. UV protection was determined in vitro through ultraviolet protection factor. Additionally, the influence to fabric whiteness and hand was researched

티타늄 실리콘 옥사이드 나노입자를 첨가제로 사용한 4-iodoaniline을 포함한 하이드로젤 착색 콘택트렌즈의 특성

목적: 4-iodoaniline을 포함한 하이드로젤 콘택트렌즈 기본 재료에 티타늄 실리콘 산화물 나노입자를 첨가하여 친수성 착색 콘택트렌즈의 물리적 및 광학적 특성을 측정하고 제조된 고분자의 자외선 투과율을 측정하여 티타늄 실리콘 옥사이드 나노입자의 자외선 차단 안의료용 렌즈 소재로의 활용도 및 4-iodoaniline만을 기본 콘택트렌즈 재료에 공중합하여 두 실험군의 물성을 비교 분석하였다. 방법: 하이드로젤 렌즈 제조를 위해, HEMA, MA, MMA, 4-iodoaniline, 교차결합제인 EGDMA 및 개시제인 AIBN을 사용하여 공중합 하였다. 또한, 티타늄 실리콘 옥사이드 나노입자는 첨가제로 사용되었다. 중합 후 제조된 콘택트렌즈 재료의 함수율, 굴절률, 접촉각 및 분광투과율 등의 물리적 특성을 측정하였다. 결과: 하이드로젤 렌즈 고분자의 물성을 측정한 결과, 함수율 35.01~ 38.68%, 굴절률 1.4350~1.4418, 접촉각 <TEX>$34.15{\sim}57.25^{\circ}$</TEX> 그리고 UV-B 투과율의 경우 1.0~10.0%의 범위로 나타났다. 또한 첨가제를 사용하지 않은 실험군에서는 함수율 34.0~36.8%, 굴절률 1.4378~1.4420, 접촉각 <TEX>$40.15{\sim}60.16^{\circ}$</TEX> 그리고 UV-B 투과율의 경우 1.8~25.0% 범위의 분포를 나타내었다. 결론: 티타늄 실리콘 옥사이드 나노입자를 첨가한 조합에서 자외선 투과율이 크게 감소하는 것으로 나타났다. Purpose: The physical and optical characteristics of hydrophilic tinted contact lens containing titanium silicon oxide nanoparticles and the basic hydrogel contact lens material containing 4-iodoaniline were examined. In this study, the utility of titanium silicon oxide nanoparticles as a UV-blocking material for ophthalmologic devices were investigated by measuring the UV transmittance of the produced polymer. Also, titanium silicon oxide nanoparticles only without the addition of 4-iodoaniline in primary contact lens materials by copolymerizing two groups were compared. Methods: For manufacturing hydrogel lens, HEMA, MA, MMA, 4-iodoaniline and a cross-linker EGDMA were copolymerized in the presence of AIBN as an initiator. Also, the titanium silicon oxide nanoparticles was used as additive. After polymerization the physical properties such as water content, refractive index, contact angle and spectral transmittance of produced contact lenses were measured. Results: Measurement of the physical properties of the copolymerized material showed that the water content, refractive index, UV-B transmittance and contact angle were in the range of 35.01~38.60%, 1.4350~1.4418, <TEX>$34.15{\sim}57.25^{\circ}$</TEX> and 1.0~10.0%, respectively. Titanium silicon oxide nanoparticles is not used as an additive in the experimental group, the results of the measurement showed that the water content, refractive index, contan angle and UV-B transmittance of the hydrogel lens polymer was 34.00~36.80%, 1.4378~1.4420, <TEX>$40.15{\sim}60.16^{\circ}$</TEX> and 1.8~25.0%, respectively. Conclusions: Also, the transmittance for UV light was reduced significantly in combinations containing titanium oxide nanoparticles.

Sensitivity of post-settlement Dreissena rostriformis bugensis to UVB radiation at Earth surface intensity levels

As quagga mussels (Dreissena rostriformis bugensis) spread through North America, it is critical to understand environmental conditions that may affect their ability to thrive, and thus potentially lead to control measures. The sensitivity of D. r. bugensis to electromagnetic radiation in the Ultraviolet-B range (UVB) is considered through experiment. Post-settlement specimens were collected from Lake Mead (southern Nevada), acclimated to laboratory conditions, and then segregated into two size classes on the basis of length; small (6–9mm) and large (13–19mm). Test groups from both size classes were exposed to continuous UVB at one of three power levels (100, 300, or 500μW/cm2) chosen to be consistent with maximal Earth surface conditions. Survivorship for both size classes was found to follow a logistic model and to scale with the square root of the applied UVB intensity. This result strongly suggests that a four-fold increase in applied power is required to double the mortality rate. Results also strongly suggest that resistance to UVB increases with size/maturity. Post-mortem measurements of shell thickness and UVB transmission demonstrate that the shells impede transmission of UVB with an effectiveness that is proportional to thickness.

The relationship between total solar radiation and biologically erythematic radiation over urban region of Egypt

Abstract This work studies the relationship between the effective of erythematic radiation (EER) and the total solar radiation ( G ) from urban region of Egypt. The measurements of total solar radiation ( G ) and biologically effective erythematic radiation (EER) incident on a horizontal surface at Cairo, Egypt (lat. 30°05′N and Long. 31°15′E), during the period time (1990–2010) are used. The relationship between hourly mean and daily mean of EER and the hourly mean daily mean totals of broadband total solar radiation is presented. The average hourly monthly mean variation of slant ozone Z and UVB transmission K tUVB at the present work are found. The relation between the two variables slant ozone Z and UVB transmission K tUVB show an opposite seasonal behavior, the low values of the slant ozone column during summer time produce high UVB transmission values in this season. The apposite pattern is observed during the winter. The Seasonal Statistical values of regression equations; the slopes ( β ), intercepts ( α ) and the standard errors (SE) for the fitted lines. The minimum slope occurs in winter, indicating that the percentage reduction in EER at higher SZA is larger than G . The variations of the slopes ( β ) during the course of the year ranges from a minimum of 0.2214 in winter to a maximum of 0.2914 in summer, the intercepts also show their minimum and maximum values in cold humid and hot dry months. The temporal variability of the percentage ratio of the total hourly mean daily erythema to total hourly mean daily broadband solar global irradiation (EER/ G ) is presented. The estimated values of UVB solar radiation a good agreement with the measured values of the UVB solar radiation, the difference between the estimated and measured values of UVB solar radiation varies from 2.3% to 3.6%.

Change of Physical Properties of Hydrogel Lens Polymer Containing Isocyanate Group with Ag Nanoparticle

A study that copolymerized Ag nanoparticle and furfuryl isocyanate with the crosslinking agent EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate), MMA (methyl methacrylate), MA (methacrylic acid) and the initiating agent AIBN (azobisisobutyronitrile) is presented. Measurement of the physical characteristics of the produced macromolecule showed that the water content is 32.08~32.67%, refractive index 1.446~1.448, visible light transparency 83.2~67.6%, contact angle <TEX>$68.2{\sim}83.5^{\circ}$</TEX> and tensile strength 0.541~0.755 kgf. It is also demonstrated that the addition of Ag nanoparticles is associated with the reduction of UV-B transmittance and increase in tensile strength. The results show that the produced copolymer can be used as a material for ophthalmic lenses with durability and UV-blocking properties.

Variation in flavonoid pattern in leaves and flowers of Primula veris of different origin and impact of UV-B

Flavonoids can serve as chemotaxonomic markers and play an important role in protection against ultraviolet (UV) radiation. Primula veris originating from two natural field sites in Albania and one cultivar from Austria were used to investigate whether flavonoid pattern may differ between populations and to determine their response to UV. Plants were grown in a common environment and shortly before flowering transferred in two greenhouses with 80% and 4% UV-B transmission, respectively. After two weeks, young leaves and open flowers were harvested and flavonoids analyzed by high performance liquid chromatography. The flavonoid profiles of leaves and flowers were highly distinct for each population, with certain flavonoids occurring only in plants of particular field sites. These flavonoids may be useful biomarkers to identify the origin of plant material. The differences in UV-treatment at that stage had no effect on the total flavonoid contents of both leaves and flowers. However, individual flavonoids of both leaves and flowers responded sensitively to UV, suggesting that they may be involved in protection against UV.

Medical physics training for radiation oncology residents in Greece

s / Physica Medica 30 (2014) e45ee74 e49 Results: Although all of the 120 sunglasses tested in this study were effective in reducing the intensity of visible light, nearly none of the sunglasses could offer efficient protection against UV radiation. The UVA and UVB transmittance of the sunglasses were in the range of 0.31% (price category of more than 150$) and 72.2% (price category of 30-90$). Conclusion: The majority of sunglasses tested in this study strongly decreased the visible light intensity but couldn’t block all UV radiation. According to the ANSI Z80.3-2001 (U.S. standard) the lens should have a UVB (280 to 315 nm) transmittance of no more than 1%. These findings lead us to this conclusion that these sunglasses can endanger the vision due to dilation of the pupil and overexposure of the lens to UV radiation. MEDICAL PHYSICS TRAINING FOR RADIATION ONCOLOGY RESIDENTS IN GREECE G. Pissakas , S. Nikoletopoulos , P. Georgolopoulou , D. Kardamakis . Hellenic Society of Radiation Oncology, Greece; Hellenic Association of Medical Physicists, Greece; Medical Physics Department, G.Anticancer Athens Hospital “Saint Savvas”, Greece Purpose: Medical physics is an essential part of recommended curricula for residents in radiation oncology (RO). With no official training programs in place, medical physics training is often incidental and incomplete for RO residents in Greece. The aim of this work is to measure the effectiveness of an educational session on medical physics offered to RO trainees of the country. Method: The Hellenic Society of Radiation Oncology (EEAO) hosts quarterly educational meetings for RO residents of all levels. On April 2013 a physics-dedicated meeting was planned for a body of 52 residents. Topics ranged from basic radiation physics, physics of radiotherapy, brachytherapy, 3DCRT, IMRT to physics of specialized treatment modalities. Attendance compared favourably to 30 previous EEAO meetings focusing on clinical issues. Assimilation of material was measured by completion of a test at the end of the meeting focused on main Learning Objectives (LO). Results: Test questions covered all sessions of the meeting with equal weights. Main Bloom’s taxonomy categories were represented. Top 3% of grades achieved corresponded to residents whose home institutes put a substantial effort in training. Students responded better to sessions of an interactive naturewith higher grades on respective LO’s but indicated their enthusiasm over sessions on cutting edge technology. Given the lack of adequately equipped training institutes in the country, this suggests the need for rotation of residents, as recommended by international guidelines on RO training programs (IAEA, ESTRO, ASTRO). Conclusions: Educational meetings for RO residents focused in medical physics are quite effective in bringing together the physics background needed in their clinical practice. The need remains for implementing official training programs throughout the country and for rotation of residents in different institutes during their training. PORTUGUESE PATHWAY TO THE IMPLEMENTATION OF THE NEW EUROPEAN GUIDELINES ON MEDICAL PHYSICS EXPERT Ana Rita Figueira , Esmeralda Poli , Jorge Isidoro , Maria do Carmo Lopes . a Professional Matters and Education and Training Technical Commissions of the Medical Physics Division of the Portuguese Physics Society (DFM-SPF); Centro Hospitalar S~ ao Jo~ ao, EPE e Porto Portugal; Centro Hospitalar Lisboa Norte, EPE e Lisboa Portugal; Centro Hospitalar Universit ario de Coimbra, EPE e Coimbra e Portugal; e Instituto Portugues de Oncologia de Coimbra de Francisco Gentil, EPE e Coimbra e

Changes in Ultraviolet Transmittance of Hydrogel and Silicone-Hydrogel Contact Lenses Induced by Wear

To evaluate the ultraviolet (UV) transmittance spectra of different contact lenses and assess the effect of wear on UV transmittance values and ocular protection factor (PF). Transmittance in the UV range (200-400 nm) of 216 contact lenses was measured before and after wear, using a spectrophotometer. The contact lenses used were ACUVUE TruEye, ACUVUE MOIST, ACUVUE OASYS, ACUVUE 2, ACUVUE DEFINE, DAILIES AquaComfort Plus, AIR OPTIX for astigmatism, FreshLook ONE-DAY lens, and Neo Cosmo. This study indicates that the following contact lenses transmitted less than the American National Standards Institute (ANSI) of 5% or less of UVB: ACUVUE DEFINE, ACUVUE MOIST, ACUVUE 2, ACUVUE TruEye, and ACUVUE OASYS. All lenses also met the ANSI standard of less than 30% transmittance of UVA except for AquaComfort Plus, AIR OPTIX for astigmatism, and Neo Cosmo. FreshLook meets the UVA transmission standard but fell short of the UVB transmission standard by 3%. FreshLook and ACUVUE MOIST had the highest calculated PF (3.9) of the hydrogel group and were unaffected after wear. Of the silicone-hydrogels (SiHs), the PF for AIR OPTIX for astigmatism was the highest (10.6) before wear and increased after wear to a PF of 13.3. The results also show that, for the UVC region, significant differences exist in transmittance values before and after wear of all SiH lenses and all hydrogel lenses, except for Neo Cosmo. FreshLook and Neo Cosmo were the only lenses that showed no statistically significant differences in the UVA transmittance after wear. Ultraviolet-blocking contact lenses were effective in blocking ultraviolet radiation to safe levels recommended by ANSI, whereas non-UV blockers such as AquaComfort Plus and AIR OPTIX for astigmatism also showed UV-attenuation capabilities greater than the values previously reported. The Neo Cosmo contact lens transmitted greater than 86% UVB and 89% UVA, making it unsuitable for UV protection seekers. Transmission is modified after contact lens wear in almost all lenses but more so in the SiH lenses, probably because of the formation of biofilms on the lens surface.

Assessment of the UVB Transmittance Measurement Uncertainty in Conformity with ISO/IEC 17025

The main purpose of this research is to construct a laboratory for testing standard. It refers to the spirit of ISO/IEC 17025 Standard, and follows Guide to the Expression of Uncertainty in Measurement (ISO GUM) made by ISO organization. The content includes UV test system construction, UVB transmittance measurement uncertainty, and the plan of measurement quality assurance that assures the stable operation of the laboratory system. Construct the equations of measurement uncertainty by the system methods that apply to the UVB transmittance measurement of car insulation film, and evaluate the variance with transmittance measurement measured by UV spectroradiometer. As for the results of transmittance measurement, the transmittance is between 0.87214 and 1.02146(%) with single wavelength of 294.5nm. There is little difference between the manufacturer label value and the measured one. The verification proofs the effectiveness of the system, and allows the tests of commercial UV-cut products fit the international and world standards.

UV–vis light transmittance through tinted contact lenses and the effect of color on values

To assess the transmittance, in the 200-700nm electromagnetic radiation spectrum, by popularly used tinted soft contact lenses (CLs). The spectra transmittances of ultraviolet (UV)-blocking (I Day Acuvue Define, Freshlook ONE DAY) and non-UV-blocking (Durasoft 3, Tutti, and NeoCosmo) tinted soft CLs were tested. The transmittance of each lens, including nine different colors of Freshlook CL was recorded on spectrophotometer, and the data used to also calculate a UV protection factor (PF) for each lens brand tested, with a higher value indicating a higher level of protection. The UV-blocking CLs significantly reduced UVC, UVB & UVA transmission and thereby meet the American National Standards Institution standard for class 2 UV blockers: a maximum of 30% transmittance of UVA and 5% transmittance of UVB wavelengths. In contrast, the Durasoft 3, Tutti, and NeoCosmo CLs demonstrated negligible UV-blockage. The Acuvue Define CL offered the greatest protection from UVC (PF=69) and UVB (PF=55), but with only 35% luminous transmittance, while the Freshlook CL (especially gemstone green) offered the best protection from UVA (PF=24) and showed about 55% translucency. Overall, the UV-blocking CLs performed equally well across the UV spectrum. Different colors of Freshlook CL transmitted statistically and clinically significantly different amounts of visible light but similar amounts of UVR. Freshlook and Acuvue Define CLs which are designated as UV-blockers significantly reduced UVR transmission to safe levels whereas Tutti, NeoCosmo and Durasoft 3 did not. Transmission within the Freshlook CL family was more dependent on color in the visible light spectrum, but not in the UV-spectrum, where the gemstone green performing best among the tested colors.