Effect of cloud on UVA and exposure to humans

The daily autumn and winter UVA exposures and 6-minute UVA irradiance data for a Southern Hemisphere, subtropical site (Toowoomba, Australia, 27.6 S, 151.9 E) are presented. This data is used to quantify the effect of cloud on UVA using an integrated sky-camera and radiation system. Additionally, an estimate of the effect of enhanced UVA exposure on humans is made. The measurement system consisted of broadband visible-infrared and UVA sensors together with a sun tracking, wide-angle video camera. The mean daily June exposure was found to be 409 kJm-2. Under the constraints of the uncertainty of both the UVA measurement system and clear-sky model, one case of enhanced UVA irradiance was found. Three cases of cloud enhancement of daily UVA exposure, approaching clear-sky levels, were also determined using a calculated clear-sky envelope. It was also determined that for a fulltime outdoor worker, the additional UVA exposure could approach approximately that of one third of a full winter's day. For indoor workers with an outside lunch break of noon to 1 pm, the additional UVA exposure was on average 6.9 kJm-2 over three cloud enhanced days. To the authors' knowledge this is the first paper to present some evidence of cloud enhanced UVA human exposure

The Effects of Ultraviolet Light on Anthocyanin Accumulation in the Adventitious Roots of Sedum wrightii (Crassulaceae)

Several studies have supported the idea that anthocyanin accumulation may be a possible protection mechanism in plants against DNA damage caused by ultraviolet radiation (UV). This study explored the accumulation of anthocyanins in the adventitious root tips of Sedum wrightii using the following treatments: UVA, UVA+low UVB, and UVA+high UVB. Following exposure to UV radiation, samples were analyzed for anthocyanin accumulation using an ethanol extraction procedure. Using ELISA, additional root samples were analyzed for indicators of DNA damage: cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone dimers (6-4 PPs). The anthocyanin concentrations were significantly higher in the UVA + high UVB treatment than the other groups. The ELISA resultsshowed that a difference occurred between the control and the treatments of UVA, UVA+low UVB and UVA+high UVB for CPDs and between the control and the UVB treatments for 6-4 PPs. Anthocyanins accumulated with increased UV exposure. However, additional research is needed to determine the significance of anthocyanins in the adventitious root tips of S. wrightii

Melanocytes are selectively vulnerable to UVA-mediated bystander oxidative signaling.

Long-wave UVA is the major component of terrestrial UV radiation and is also the predominant constituent of indoor sunlamps, both of which have been shown to increase cutaneous melanoma risk. Using a two-chamber model, we show that UVA-exposed target cells induce intercellular oxidative signaling to non-irradiated bystander cells. This UVA-mediated bystander stress is observed between all three cutaneous cell types (i.e., keratinocytes, melanocytes, and fibroblasts). Significantly, melanocytes appear to be more resistant to direct UVA effects compared with keratinocytes and fibroblasts, although melanocytes are also more susceptible to bystander oxidative signaling. The extensive intercellular flux of oxidative species has not been previously appreciated and could possibly contribute to the observed cancer risk associated with prolonged UVA exposure

Gender peer effects in university: Evidence from a randomized experiment

Recent studies for primary and secondary education find positive effects of the share of girls in the classroom on achievement of boys and girls. This study examines whether these results can be extrapolated to post-secondary education. We conduct an experiment in which the shares of girls in workgroups for first year students in economics and business are manipulated and students are randomly assigned to these groups. Boys tend to postpone their dropout decision when surrounded by more girls, and there is also a modest reduction in early absenteeism. On the other hand, boys perform worse on courses with high math content when assigned to a group with many girls. Overall, however, we fail to find substantial gender peer effects on achievement. This in spite of the fact that students in groups with many girls help each other more often and study together more often.Field experiment, Peer effects, University students

UVA Assisted 4-Thiothymidine for Cancer Treatment

This article reviews the developments of 4-thiothymidine analogues, assisted with UVA light, as a novel cancer therapy. First, the key points on synthetic chemistry, photochemistry and cellular toxicity of 4-thiothymidine are summarized. As the chemical structure of 4-thiothymidine is very similar to that of its parent thymidine, thus 4-thiothymidine can be readily incorporated into cellular DNA, and with the help of thymidine kinase, much more preferably into cancerous DNA. Unlike thymidine, 4-thiothymdine can absorb strongly in UVA (longer wavelengths of UV) light. Thus UVA-assisted 4-thiothymidine offers an effective cancer treatment. Some underlying mechanisms of action by 4-thiothymidine/UVA and compares this cancer approach with the commonly used photodynamic therapy are discussed. The various interactions between 4-thiothymidine with human serum albumin are introduced. Finally, a short conclusion on the past efforts and a brief prospect for future work in this exciting research field are given

Italian and Croatian Urban Planning: A Comparative Analysis

Croatian and Italian coasts get involved in seasonal tourism that affects the equilibrium of cities. This phenomenon causes many specific problems that can be solved by suitable urban planning strategies. The actual Croatian coast development seems to replay the situation of the Italian coast 20 years ago: in both cases, the absence of adequate planning causes inability to manage and control urban growth. With respect to these general issues, the author aims at identifyng the planning framework instituted in Italy and in Croatia, through the comparative analysis of local and regional planning instruments such as guidelines, directives and prescriptions for actual and future plans. This study concerns mainly the two coastal areas of Molise, in Italy, and of Split-Dalmacija and Dubrovnik-Neretva counties, in Croatia. The author illustrates how a lack of a suitable physical planning is a serious threat to the development of coastal areas. One of the main causes is that the actual local and regional devices are unable to answer positively to environmental and landscape emergencies, especially in Croatia. Some of the main themes analysed are the following: road and railway systems, architectural, environmental and natural resources, industrial and tourist growth. The planning process has a strategical and leading role in urban governance, both in preliminary and in putting in act phase, in order to reach a sustainable development of the territory. Some interesting results emerge from the comparison of the two government systems and from the resources still available in Italy and in Croatia. These results are useful for continuing the research of development strategies to enhance the territorial value in a compatible way with needs of environmental and nature protection.The planning design guidelines, based on the development capability assessment of the territory, should be answer the requirements of sustainability and valorisation of local resources. This study has been accomplished by the GES.S.TER. Interreg III A Adriatic Cross Border (the Head of this Project is prof. Donatella Cialdea, University of Molise, and the Cross Border Partner is University of Split). The author is a PhD student in “Landscape Analysis and Valorisation†by University of Molise, Italy.

N‐heterocyclic carbene catalyzed photoenolization/Diels–Alder reaction of acid fluorides

The combination of light activation and N‐heterocyclic carbene (NHC) organocatalysis has enabled the use of acid fluorides as substrates in a UVA‐light‐mediated photochemical transformation previously observed only with aromatic aldehydes and ketones. Stoichiometric studies and TD‐DFT calculations support a mechanism involving the photoactivation of an ortho‐toluoyl azolium intermediate, which exhibits “ketone‐like” photochemical reactivity under UVA irradiation. Using this photo‐NHC catalysis approach, a novel photoenolization/Diels–Alder (PEDA) process was developed that leads to diverse isochroman‐1‐one derivatives

Higher Education and Membership of Voluntary Groups

This research uses the British National Child Development Study to examine the effect of higher education on individual membership of voluntary groups and organizations. Gender differences in the education effects are given emphasis. We apply parametric and nonparametric econometric methods to isolate the influence of confounding variables. There is strong evidence of education endogeneity in the female sample and we observe a negative education effect on women's group membership. Education endogeneity does not cause serious estimation bias in the male sample. Higher education is a significantly positive determinant of men's group membership. Further investigations from a mid-life perspective reveal that the boost of female participation in the workforce and their attitudes towards employment are key factors in the negative association between higher education and women's group membership. Our research provides clues for the divergence in the enrolment in higher education and social participation behavior in Western countries.