Academic literature on the topic 'UV risk analysis'

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Journal articles on the topic "UV risk analysis"

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Beretich, BD, and TM Beretich. "Explaining multiple sclerosis prevalence by ultraviolet exposure: a geospatial analysis." Multiple Sclerosis Journal 15, no. 8 (August 2009): 891–98. http://dx.doi.org/10.1177/1352458509105579.

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Background Epidemiologic studies have shown a positive correlation of multiple sclerosis (MS) prevalence with latitude. However, there has not been a causal association found. Increased dietary intake and increased serum levels of vitamin D showed to be protective for the development of MS. Ultraviolet (UV) radiation plays an important role in vitamin D synthesis and could potentially explain both latitude differences in MS prevalence and the low levels of vitamin D in individuals with MS. Objective To evaluate the relationship between UV radiation and MS prevalence using geospatial analysis. Methods Geospatial analysis was performed on North American regions and separately for the continental United States. The correlation of UV radiation (measured as UV index [UVI]) versus MS prevalence and UV radiation versus case-control ratios was calculated. In addition, the relative risk (RR) of MS was determined for regions/states with low UV radiation exposure. Results Case-control ratios by US state and MS prevalence by North American region showed a strong negative (inverse) correlation with UVI ( R = −0.72 and −0.86, respectively). The RR for the five highest risk states/lowest UVI versus the five lowest risk states/highest UVI was increased (RR = 1.8–5.4). The RR for MS, when comparing North American regions with lowest and highest UVI, was 3.78 and within US regions was 1.52. Conclusion This analysis suggests a strong association between UV radiation and MS distribution, and an increase in risk for MS in those areas with a low UVI.
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Boere, Tjarda M., Douwe H. Visser, A. Marceline van Furth, Paul Lips, and Frank G. J. Cobelens. "Solar ultraviolet B exposure and global variation in tuberculosis incidence: an ecological analysis." European Respiratory Journal 49, no. 6 (June 2017): 1601979. http://dx.doi.org/10.1183/13993003.01979-2016.

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Epidemiological evidence supports vitamin D deficiency as a risk factor for tuberculosis. Differences in solar ultraviolet B (UV-B) exposure, the major source of vitamin D, might therefore partially explain global variation in tuberculosis incidence.In a global country-based ecological study, we explored the correlation between vitamin D-proxies, such as solar UV-B exposure, and other relevant variables with tuberculosis incidence, averaged over the period 2004–2013.Across 154 countries, annual solar UV-B exposure was associated with tuberculosis incidence. Tuberculosis incidence in countries in the highest quartile of UV-B exposure was 78% (95% CI 57–88%, p<0.001) lower than that in countries in the lowest quartile, taking into account other vitamin D-proxies and covariates. Of the explained global variation in tuberculosis incidence, 6.3% could be attributed to variations in annual UV-B exposure. Exposure to UV-B had a similar, but weaker association with tuberculosis notification rates in the multilevel analysis with sub-national level data for large countries (highestversuslowest quartile 29% lower incidence; p=0.057).The potential preventive applications of vitamin D supplementation in high-risk groups for tuberculosis merits further investigation.
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Molot, L. A., W. Keller, P. R. Leavitt, R. D. Robarts, M. J. Waiser, M. T. Arts, T. A. Clair, et al. "Risk analysis of dissolved organic matter-mediated ultraviolet B exposure in Canadian inland waters." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 12 (December 1, 2004): 2511–21. http://dx.doi.org/10.1139/f04-165.

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With depleted ozone levels and the possibility that climate change might lower dissolved organic matter (DOM) concentrations, the risk of exposure of fresh waters in Canada to ultraviolet B (UV-B) was evaluated. First, the distribution of a UV-B-sensitive zooplankton genus, Daphnia, was examined as a function of DOM concentration and maximum depth (Zmax) in 258 systems. Distribution was not restricted by UV-B, although very clear, shallow systems are underrepresented. Secondly, the depth at which 1% of surface radiance at 320 nm occurs (Z320,1%) was compared with Zmax in over 1000 aquatic systems in 15 ecozones to determine the proportions of optically clear systems (Zmax ≤ Z320,1%) and systems that may become clear (i.e., are "at risk") should DOM decrease by 50%. South of the treeline, <6% of systems were clear, with the exception of two ecozones with 10%–20%. The proportion of systems at risk was 0% in most regions, with 5%–9% in four regions. DOM levels appear adequate to prevent extirpation of sensitive taxa like Daphnia through direct exposure to UV-B in most regions south of the treeline. However, optically clear and at-risk ponds were much more common in the three Artic ecozones, especially the Northern Arctic and Arctic Cordillera.
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Monnereau, Alain, Sally L. Glaser, Clayton W. Schupp, Karin Ekström Smedby, Silvia de Sanjosé, Eleanor Kane, Mads Melbye, et al. "Exposure to UV radiation and risk of Hodgkin lymphoma: a pooled analysis." Blood 122, no. 20 (November 14, 2013): 3492–99. http://dx.doi.org/10.1182/blood-2013-04-497586.

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Key Points Our pooled analysis found an inverse association between several measures of UVR exposure and Hodgkin lymphoma. Significant UVR-related inverse associations of EBV-positive HL with a dose-response relationship support etiologic heterogeneity in HL.
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Clare, John F. "Calibration of UV–vis spectrophotometers for chemical analysis." Accreditation and Quality Assurance 10, no. 6 (May 5, 2005): 283–88. http://dx.doi.org/10.1007/s00769-005-0927-1.

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Strouse, John J., Thomas R. Fears, Margaret A. Tucker, and Alan S. Wayne. "Pediatric Melanoma: Risk Factor and Survival Analysis of the Surveillance, Epidemiology and End Results Database." Journal of Clinical Oncology 23, no. 21 (July 20, 2005): 4735–41. http://dx.doi.org/10.1200/jco.2005.02.899.

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Purpose To evaluate risk factors for the development of and factors influencing survival in pediatric melanoma. Patients and Methods We evaluated 1,255 children (age < 20 years) and 2,673 young adults (age 20 to 24 years) with melanoma in the 2001 National Cancer Institute (NCI) Surveillance, Epidemiology and End Results (SEER) database. We estimated exposure to UV radiation based on Environmental Protection Agency (EPA) measurements. Results The incidence of pediatric melanoma increased 46% (95% CI, 40 to 52) per year of age and 2.9% (95% CI, 2.1 to 3.6) per year from 1973 to 2001. Incidence rates were lower in black patients (−95%; 95% CI, −98 to −90) compared with white patients and in male patients (−39%; 95% CI −46 to −31) compared with females. Increased ambient UV radiation was associated with elevated risk (19% per kJ; 95% CI, 9 to 30). Children with melanoma had a 5-year melanoma-specific survival of 93.6% (95% CI, 91.9 to 94.9), which improved from 1973 to 2001. The hazard ratio of death from melanoma increased with male sex; older age; advanced disease; location of the primary other than extremities or torso; earlier year of diagnosis; and previous cancer. Conclusion The incidence of melanoma in the United States is increasing rapidly in children. Risk factors for pediatric melanoma include being white, being female, increasing age, and environmental UV radiation. Survival is decreased for children and adolescents with unfavorable prognostic factors (male sex, unfavorable site, and/or second primary or regional or distant metastasis). More effective therapeutic strategies are needed for these groups.
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DUFFY, SIOBAIN, JOHN CHUREY, RANDY W. WOROBO, and DONALD W. SCHAFFNER. "Analysis and Modeling of the Variability Associated with UV Inactivation of Escherichia coli in Apple Cider." Journal of Food Protection 63, no. 11 (November 1, 2000): 1587–90. http://dx.doi.org/10.4315/0362-028x-63.11.1587.

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Raw data from validation studies of UV tubes used for nonthermal pathogen reduction in apple cider underwent comprehensive statistical analysis. Data from each tube that demonstrated at least a 5-log reduction of Escherichia coli ATCC 25922, a surrogate for E. coli O157:H7, in each of three trials were used in the analysis. The within- and between-tube variability was calculated for 70 tubes. The mean log reductions of the tubes fit a Beta distribution (Kolmogorov-Smirnov test, 0.0246), and the between-replicate variability followed a logistic distribution (Kolmogorov-Smirnov test, 0.0305). These two distributions can be used together to model UV cider treatment as part of an overall E. coli O157:H7 in cider risk assessment. Examples of codes from @RISK and Analytica to describe these distributions, such as one would find in a quantitative risk assessment, are included.
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Messina, Gabriele, Davide Amodeo, Alessio Corazza, Nicola Nante, and Gabriele Cevenini. "Analysis of the physical and microbiocidal characteristics of an emerging and innovative UV disinfection technology." BMJ Innovations 8, no. 1 (December 3, 2021): 21–28. http://dx.doi.org/10.1136/bmjinnov-2021-000790.

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IntroductionSurface disinfection is one of the key points to reduce the risk of transmission both in healthcare and other public spaces. A novel UV-chip disinfection technology is presented. Technological, photonic and microbiocidal characteristics are evaluated taking as reference an ultraviolet-C (UV-C) LED source of equivalent radiant power.MethodsThe UV chip has a circular radiating surface with a diameter of 1.3 cm, emitting UV cold light at about 5 mW and driven current of about 80 µA. Four bacterial strains were used to conduct the microbiological tests at 4°C and 60°C to evaluate the bactericidal performance of the two technologies under the same operating conditions.ResultsSpectral differences were found between the UV-C LED and the chip, with an emission curve strictly around 280 nm and a broader band centred around 264 nm, respectively. Between-technology microbiological inactivation levels were comparable, achieving total abatement (99.999%) in 8 min at 7.5 cm.DiscussionThe UV chip exhibits unique properties that make it applicable in some specific contexts, where UV-C LEDs present the most critical issues. Besides, it is portable and exhibits a broad spectrum of UV wavelengths with a peak where the maximum microbiocidal efficacy occurs. Important issues to be addressed to improve this technology are the high voltage management and the too low energy efficiency.ConclusionThis cold emission technology is virtually unaffected by changes in ambient temperature and is particularly useful in short-distance applications. Recent developments in technology are moving towards a progressive increase in the chip’s radiant power.
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O'Keefe, Ryan M., Michael Joseph LaRiviere, Carolyn Vachani, Margaret K. Hampshire, Christina Bach, Karen Arnold-Korzeniowski, Marisa Healy, James M. Metz, and Christine E. Hill-Kayser. "Contribution of family history of melanoma to associated risk factors: Analysis of an Internet-based risk assessment tool." Journal of Clinical Oncology 39, no. 15_suppl (May 20, 2021): 10546. http://dx.doi.org/10.1200/jco.2021.39.15_suppl.10546.

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10546 Background: Risk factors for melanoma (ML) include UV exposure, sunburns, multiple nevi, and fair skin. Smoking and alcohol use may also play a role. Demographics associated with increased UV exposure include male gender, white race, age 18-29, and high-income. Those with family history (FH) of ML have increased risk of developing ML themselves yet are often unaware or do not engage in preventive behaviors. We sought to understand the association between FH of ML and other personal risk factors for cancer. Methods: Since 2009, voluntary participants could receive personalized information regarding their cancer risk via the OncoLink.org Reduce My Risk tool. Survey data was collected on demographics, FH, risk-factors, and risk-associated behaviors. Use of data was IRB approved. Differences between respondents with v. without FH of ML were analyzed using chi-square test and adjusted via logistic regression. Results: 25255 responses were analyzed; 1928 (7.6%) had FH of ML. Of these, median age was 26 (range 18-75), 73.1% were female, 88.6% from North America, 91.4% White, 78.2% had at least some college, and 62.0% household income > $45,000. Comparing those with FH of ML to those without, no significant differences were observed in education, income, or home setting. Those with a FH of ML were less likely to be “light” smokers ( < 1 pack per day) but were more likely to be both “light” drinkers and “heavy” drinkers (Table). There were no significant differences in BMI or exercise habits. Those with FH of ML were more likely to sunbathe, to have had “blistering” sunburns, have 50+ moles, show signs of sun damage on their skin, and have dysplastic nevi (Table). There were no differences in use of indoor tanning beds (Table). Conclusions: Those with a FH of ML were more likely to sunbathe and to report skin damage and history of blistering sunburns; they were more likely to use tanning beds, though not statistically significant. These behaviors are modifiable and may suggest parental influence on sun-protective behaviors. Those with FH also reported increased non-modifiable risks. Future work should continue to explore targeted intervention for those with a FH of ML to educate on risk and promote sun-protective behaviors.[Table: see text]
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Salamekh, Samer, Jingsheng Yan, Hong Zhu, and Kevin V. Albuquerque. "Preoperative chemotherapy for advanced endometrial cancer-registry analysis of outcomes." Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020): 6088. http://dx.doi.org/10.1200/jco.2020.38.15_suppl.6088.

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6088 Background: Hysterectomy followed by risk-adjusted adjuvant treatment is the standard of care for staging and treatment of locally advanced endometrial cancer. Up-front surgery is difficult in some locally advanced cases with extensive local invasion since negative margins may not be achievable. Pre-operative systemic treatment may be used to shrink the tumor and facilitate resection, echoing the experience from ovarian cancer. There is limited data for this paradigm in endometrial cancer. Methods: The National Cancer Database (NCDB) was queried for cases with FIGO stage III/IV endometrial cancer (serous, clear cell, or endometrial histology) who underwent surgery and had known chemotherapy/radiation sequencing. Those who received pre-operative chemotherapy +/- post-operative chemotherapy (PreCT) were compared to those who received post-operative chemotherapy alone (PostCT). PreCT cases were considered to be initially borderline resectable or unresectable. Downstaging was determined by comparing clinical and pathologic T-stage. Univariable (UV) and multivariable (MV) analyses were performed, with statistically significant values reported. Results: 12,310 cases in PostCT and 1,059 cases in PreCT were included in the analysis. Pre-CT cases were more likely to have higher AJCC T-stage, clinically positive nodes, serous histology, higher grade, and positive surgical margins (28% compared to 16%). Overall survival (OS) was lower for PreCT compared to PostCT (HR = 2.18 UV; HR = 1.87 MV). 20% of patients who received PreCT were down-staged compared to 2% in PostCT group. Patients who were downstaged with PreCT were more likely to achieve negative margins (OR 0.36 UV) and had improved OS compared to those whose stage did not change (HR = 0.61 UV; HR = 0.37 MV). Positive margins portended worse OS for both PreCT (HR = 1.93 UV) and PostCT (HR = 2.63 UV). Negative margins in PreCT had improved OS compared to positive margins in PostCT (HR = 1.2 UV; 2.67 MV). Post-operative radiation benefited both PreCT (HR = 0.45 UV; HR = 0.34 MV) and PostCT groups (HR = 0.48 UV; HR 0.64 MV). Conclusions: Preoperative chemotherapy increased the number of patients who were downstaged and those who were downstaged were more likely to achieve a negative margin. Patients who achieved negative margins in PreCT had improved OS compared to those with positive margins in PostCT. Adjuvant radiation further improved OS in both cohorts. Pre-operative chemotherapy can be considered for patients with unresectable/borderline resectable locally advanced endometrial cancer.
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Dissertations / Theses on the topic "UV risk analysis"

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Jenkins, Toni E. "Introgression of genes from rape to wild turnip." Lincoln University, 2005. http://hdl.handle.net/10182/1844.

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Introgression of genes from crops into ruderal populations is a multi-step process requiring sympatry, synchronous flowering, chromosomal compatibility, successful pollination and development of the zygote, germination, establishment and reproduction of hybrid progeny. The goal of this thesis was to generate data on as many steps in this process as possible and integrate them into a predictive statistical model to estimate the likelihood of successful introgression under a range of scenarios. Rape (Brassica napus) and wild turnip (B. rapa var. oleifera) were used as a model system. A homozygous dominant mutation in the rape genome conferring herbicide resistance provided a convenient marker for the study of introgression. Potential differences between wild turnip populations from a wide range of geographic locations in New Zealand were examined. Hand pollination established the genetic compatibility of rape and wild turnip and a high potential for gene introgression from rape to wild turnip. Interspecific hybrids were easily generated using wild turnip as the maternal plant, with some minor differences between wild turnip populations. The frequency of successful hybridisation between the two species was higher on the lower raceme. However, the upper raceme produced more dormant interspecific hybrid seed. Field trials, designed to imitate rare rape crop escapes into the ruderal environment, examined the ability of rare rape plants to pollinate wild turnip plants over four summers. At a ratio of 1 rape plant for every 400 wild turnip plants, the incidence of interspecific hybridisation was consistently low (<0.1 to 2.1 % of total seed on wild turnip plants). There was a significant year effect with the first season producing significantly more seed and a greater frequency of interspecific hybrid progeny than the other years. The frequency of interspecific hybrid progeny increases when the ratio of rape: wild turnip plant numbers increases. The relative importance of anemophily and entomophily in the production of interspecific hybrids was examined. Wild turnip plants produced twice as many seeds with bee pollination relative to wind pollination. However, the frequency of interspecific hybrids under wind pollination was nearly twice that for bee pollination. Light reflectance patterns under UV light revealed a marked difference between wild turnip and rape flowers compared to near identical appearance under visible light. The data indicates that bees are able to distinguish between rape and wild turnip flowers and exhibit floral constancy when foraging among populations with these two species. Hybrid survival in the seed bank, germination and seedling establishment in the field are important components of fitness. Seed banks established in the soil after the field trials described above germinated in subsequent spring seasons. The predominantly brassica weed populations were screened for herbicide resistance and the numbers of interspecific hybrids germinating compared to the original frequency in the field trial results. Frequency of interspecific hybrids was reduced in the populations compared to the original seed deposit. Seed with a known frequency of interspecific hybrid seed was sown in a separate trial, and the frequency of interspecific hybrids compared at 0, 4, 6, and 8 weeks after sowing. Poor germination resulted limited competition between seedlings, however the frequency of interspecific hybrids declined over time indicating low plant fitness. There were no significant population effects on any parameters tested. Interspecific hybrids grown in a glasshouse were backcrossed to the parental species and selfed within the plant and within populations. Pollen from the interspecific hybrids was found to have markedly reduced fertility. Interspecific hybrid plants had low female fertility, with the majority (88%) of the pollinated flowers aborting the siliques. Of the remaining siliques, most (98%) had only one to three seeds per silique. Inheritance of the herbicide resistance gene was regular in backcrosses but highly skewed following self pollination with an excess of herbicide-sensitive progeny. Production of a stochastic predictive model integrated the information acquired over the practical work phase of this thesis and utilised the capabilities of @risk, a new application of a risk analysis tool. The three outputs examined were the number of flowering plants resulting from backcrosses to rape and wild turnip and self pollination of the interspecific hybrid progeny. Five scenarios were modelled and all demonstrated the high likelihood of introgression failure in this system. In all scenarios, >75% of simulations resulted in no interspecific hybrid progeny surviving to flowering in the third generation. In all scenarios, and for all three outputs, the seed set on the interspecific hybrids of the second generation was the major factor that limited the number interspecific hybrid progeny surviving to flowering in the third generation.
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Abdul, Halim Nadiya. "Quantitative Fr 13 Failure Modelling of Uv Irradiation for Potable Water Production – Demonstrated with Escherichia Coli." Thesis, 2017. http://hdl.handle.net/2440/119334.

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Steady-state ultraviolet (UV) irradiation for potable water production is becoming an important global alternative to traditional disinfection by chlorination. Failure of UV to reduce the number of viable contaminant pathogens however can lead to enduring health legacies (with or without fatalities). To better understand vulnerability of UV operations to failure, the probabilistic Fr 13 risk framework of Davey and co-workers1 is applied for the first time in this thesis. Fr 13 is predicated on underlying chemical engineering unit-operations. It is based on the hypothesis that naturally occurring, chance (stochastic) fluctuations about the value of ‘set’ process parameters can unexpectedly combine and accumulate in one direction and leverage significant change across a binary ‘failure– not failure’ boundary. Process failures can result from the accumulation of these fluctuations within an apparent steady-state process itself. That is to say, even with good design and operation of plant, there can be unexpected (surprise and sudden) occasional failures without ‘human error’ or ‘faulty fittings’. Importantly, the impact of these naturally occurring random fluctuations is not accounted for explicitly in traditional chemical engineering. Here, the Fr 13 risk framework is applied for the first time to quantitatively assess operations of logically increasing complexity, namely, a laminar flow-through UV reactor, with turbulent flow in a concentric annular-reactor, both with and without suspended solids present (Davey, Abdul-Halim and Lewis, 2012; Davey and Abdul-Halim, 2013; Abdul-Halim and Davey, 2015; 2016), and; a two-step ‘global’ risk model of combined rapid-sand-filtration and UV irradiation (SF-UV) (Abdul-Halim and Davey, 2017). The work is illustrated with extensive independent data for the survival of viable Escherichia coli - a pathogenic species of faecal bacteria widely used as an indicator for health risk. A logical and step-wise approach was implemented as a research strategy. UV reactor unit-operations models are first synthesized and developed. A failure factor is defined in terms of the design reduction and actual reduction in viable E. coli contaminants. UV reactor operation is simulated using a refined Monte Carlo (with Latin Hypercube) sampling of UV lamp intensity (I), suspended solids concentrations [conc] and water flow (Q). A preliminary Fr 13 failure simulation of a single UV reactor unit-operation (one-step), developed for both simplified laminar flow and turbulent flow models, showed vulnerability to failure with unwanted survival of E. coli of, respectively, 0.4 % and 16 %, averaged over the long term, of all apparently successful steady-state continuous operations. A practical tolerance, as a design margin of safety, of 10 % was assumed. Results from applied ‘second-tier’ studies to assess re-design to improve UV operation reliability and safety and to reduce vulnerability to Fr 13 failure showed that any increased costs to improve control and reduce fluctuations in raw feed-water flow, together with reductions in UV lamp fluence, would be readily justified. The Fr 13 analysis was shown to be an advance on alternate risk assessments because it produced all possible practical UV outcomes, including failures. A more developed and practically realistic model for UV irradiation for potable water production was then synthesized to investigate the impact of the presence of suspended solids (SS) (median particle size 23 μm) as UV shielding and UV absorbing agents, on overall UV efficacy. This resulted in, respectively, some 32.1 % and 43.7 %, of apparent successful operations could unexpectedly fail over the long term due, respectively, to combined impact of random fluctuations in feed-water flow (Q), lamp intensity (I0) and shielding and absorption of UV by SS [conc]. This translated to four (4) failures each calendar month (the comparison rate without suspended solids was two (2) failures per month). Results highlighted that the efficacy of UV irradiation decreased with the presence of SS to 1-log10 reduction, compared with a 4.35-log10 reduction without solids present in the raw feed-water. An unexpected outcome was that UV failure is highly significantly dependent on naturally occurring fluctuations in the raw feed-water flow, and not on fluctuations in the concentration of solids in the feed-water. It was found that the initial presence of solids significantly reduced the practically achievable reductions in viable bacterial contaminants in the annular reactor, but that fluctuations in concentration of solids in the feed-water did not meaningfully impact overall vulnerability of UV efficacy. This finding pointed to a pre-treatment that would be necessary to remove suspended solids prior to the UV reactor, and; the necessity to improve control in feed-water flow to reduce fluctuations. The original synthesis was extended therefore for the first time to include a rapid sand-filter (SF) for pre-treatment of the raw feed-water flow to the UV reactor, and; a Fr 13 risk assessment on both the SF, and sequential, integrated rapid sand-filtration and UV reactor (SF-UV). For the global two-step SF-UV results showed vulnerability to failure of some 40.4 % in overall operations over the long term with a safety margin (tolerance) of 10 %. Pre-treatment with SF removed SS with a mean of 1-log10 reduction (90 %). Subsequently, an overall removal of viable E. coli from the integrated SF-UV reactor was a 3-log10 reduction (99.9 %). This is because the efficacy of UV light to penetrate and inactivate viable E. coli, and other pathogens, is not inhibited by SS in the UV reactor. This showed that the physical removal of E. coli was accomplished by a properly functioning SF and subsequently disinfection was done by UV irradiation to inactivate viable E. coli in the water. Because the Regulatory standard for potable water is a 4-log10 reduction, it was concluded that flocculation and sedimentation prior to SF was needed to exploit these findings. Flocculation is a mixing process to increase particle size from submicroscopic microfloc to visible suspended particles prior to sedimentation and SF. This research will aid understanding of factors that contribute to UV failure and increase confidence in UV operations. It is original, and not incremental, work. Findings will be of immediate interest to risk analysts, water processors and designers of UV reactors for potable water production.
Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering & Advanced Materials, 2017
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Book chapters on the topic "UV risk analysis"

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Hannuksela-Svahn, A., B. Sigurgeirsson, E. Pukkala, B. Lindelöf, B. Berne, M. Hannuksela, K. Poikolainen, and J. Karvonen. "Trioxsalen Bath PUVA Does Not Increase the Risk of Squamous Cell Skin Carcinoma: A Joint Analysis of 1124 Swedish and Finnish Patients Followed Up for 10 Years." In Skin Cancer and UV Radiation, 434–39. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_49.

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Conference papers on the topic "UV risk analysis"

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Arenberg, Jonathan W., and William W. Zhang. "Analysis of the cost, schedule, and risk for Lynx mirror assembly production." In UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI, edited by Oswald H. Siegmund. SPIE, 2019. http://dx.doi.org/10.1117/12.2529696.

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Saiki, Naoya, Yuichiro Komasu, Kazuto Aizawa, and Jun Maeda. "Investigation of Peeling Behavior of UV Curable Pressure Sensitive Adhesive for Bump-Wafer." In ASME 2017 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems collocated with the ASME 2017 Conference on Information Storage and Processing Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/ipack2017-74010.

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In this study, the peeling process of UV-curable pressure sensitive adhesive tape from bump wafer is investigated through the use of finite element analysis, observation of high speed video, and actual wafer back-grinding process testing. In our experiment, a large deformation of adhesive is observed at the edge of bottom of bump, appearing on the side of the bump opposite tape-peeling direction when observed with high speed microscope video. The largely deformed adhesive creates a string shaped elongation. The adhesive residue is caused by the fracture of the adhesive string. We investigated how to generate the adhesive string in the tape-peeling process through the use of finite element analysis. In this analysis, a cohesive element is introduced into the adhesive layer. The analytical result shows the adhesive string at the same position of experiment and the stress distribution is different between the string part and the other area of adhesive. The influence of peeling angle and bump size is also investigated by the same finite element model. As a result, higher peeling angle and smaller bump sizes shows a shorter adhesive string, which lowers the risk of adhesive residue.
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Gaidelys, Vaidas, and Emilija Naudžiūnaitė. "EMPIRICAL ANALYSIS OF THE EFFECTS OF DIFFERENT SPECTRUM UV AND HINS RAYS ON COVID-19 AND IMPACT OF ECONOMIC PROCESS AND FOR THE MANUFACTURE OF PRODUCTS." In 12th International Scientific Conference „Business and Management 2022“. Vilnius Gediminas Technical University, 2022. http://dx.doi.org/10.3846/bm.2022.726.

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In late 2019, a new coronavirus, known as a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified as a cause of numerous pneumonia cases in Wuhan, a city in Hubei Province, China. This virus quickly spread and caused a global pandemic. 2020, the World Health Organisation (WTO) named the new coronavirus dis-ease COVID-19. Most coronaviruses are non-hazardous, but the new virus that causes COVID-19 is an exception to the rule. The purpose of this article was to evaluate the effects of different spectra of UV and HINS rays on COVID-19 and their market introduction in the context of global demand. There are three main tasks of the study. First, verifica-tion of the latest COVID-19 virus studies in terms of accuracy and test duration, depending on whether a sample is taken from surfaces or from an aerosol. Second, comparison of COVID-19 identification by employing viral polymer-ase chain reaction (PCR), antigen detection and other methods. Third, economic description and justification of the testing algorithm. The results indicate that SARS-CoV-2 is a highly contagious coronavirus that causes COVID-19 and is transmitted through air droplets and aerosols as well as through close contacts. The high risk of SARS-CoV-2 spread in confined spaces and through aerosol-generating medical procedures has been confirmed. SARS-CoV-2 can remain viable in air in liquid droplets <1 µm in diameter for up to 3 hours. Aerosol (<5 μm) SARS-CoV-2 persists longer on plastic and stainless steel than on copper and cardboard. SARS-CoV-2 is sensitive to ultraviolet light. The use of UV and HINS rays in the production of COVID-19 products also has a significant impact on national economies.
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Heiremans, J., M. Claeys, and A. G. Herman. "DETERMINATION OF CHOLESTERYL HYDROXYOCTADBCADIENOATES IN VASCULAR TISSUE BY HPLC AND ITS RELEVANCE TO ATHEROSCLEROSIS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643084.

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Accumulation of lipids in the intimal arterial layer, and of cholesterol esters in particular, has been recognised as an early and prominent phenomenon in atherogenesis. Several attempts have been made to link putative peroxidation of these lipids in vivo to causal or deteriorating etiological determinants of plaque formation. The occurrence in advanced human atheromata of oxidized derivatives of cholesteryl linoleate -a major polyunsaturated cholesterol ester species in plasma and vessel wall - has been described by Brooks et al. (Atherosclerosis, 1970,13,223) and a positive correlation between the amount of cholesteryl hydroxyoctadecadienoates (CHODES) and the stage of the lesion has also been reported. In addition Funk and Powell (J. Biol. Chem., 1985,260,7481) have found hydroxyoctadecadienoic acids in normal aorta of different species, wich were strikingly increased after alkaline hydrolysis of total lipids, and this in contrast with the arachidonic acid analogs. The aim of this study was to develop a sensitive and practical method for specific assay of CHODES, without resorting to laborious saponification and derivatisation procedures required for gas chromatographic analysis, which could moreover augment the risk for artefacts.Dog thoracal aorta was homogenised and lipids were extracted using the Folch method with CHCl3/CH30H;2/l containing 0.05mM butylated hydroxytoluene. Fractionation of CHODES from neutral lipids was carried out by thin-layer chromatography. For detection and quantification a high-performance liquid chromatography (HPI/2) assay method was developed, with UV monitoring at 232nm , a wavelength characteristic for conjugated dienes with vicinal hydroxyl function. Reference compounds and the internal standard for HPLC analysis were synthesized from linoleic acid and 10,13,16-docosatrienoic acid, respectively, by preparation of hydroxy fatty acids with soybean lipoxygenase and subsequent esterification to cholesterol esters with pancreas cholesterol esterase. Confirmation of the structural identity was obtained by mass spectrometry. Artefactual formation of CHODES ex vivo was investigated by subjecting radiolabeled cholesteryl linoleate through the analysis procedure. This method allows the specific detection of CHODES in non-atherosclerotic arteries which was hitherto only reported for human advanced atherosclerotic lesions and is proposed as a sensitive and specific probe for prospective survey of lipid peroxidation in atherosclerotic blood vessels.
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5

Yoo, Sang-Yeoun, and Yogesh Jaluria. "Convective Transport in an Optical Fiber Coating Applicator for a Non-Newtonian Fluid." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79642.

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Convective transport in an optical fiber coating applicator and die system has been simulated for a non-Newtonian fluid. Low density Polyethylene (LDPE) is employed for the numerical analysis, though ultraviolet (UV) curable acrylates are commonly used, because of lack of property information for acrylates and similar behavior of these two materials. The equations governing fluid flow and heat transfer are transformed to obtain flow in a cylindrical domain. A SIMPLE-based algorithm is used with a non-uniform grid. In contrast to the isothermal case, streamlines for the non-Newtonian fluid are found to be quite different for various fiber speeds. The temperature level in the applicator is much higher for the Newtonian case, due to the larger fluid viscosity and associated viscous dissipation. The shear near the fiber is found to be lower for the Newtonian fluid. As expected, the effects become larger with increasing fiber speed. A very high temperature rise is observed in the die, regardless of fiber speed. This study focuses on the non-Newtonian effects during the coating process, and several interesting and important features, as compared to the Newtonian case, are observed.
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Vijayaraghavan, Prasant, and Vishnu-Baba Sundaresan. "Investigating Secondary Equilibration in Thermoplastic Ionomers Under a Thermo-Electric Field." In ASME 2016 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/smasis2016-9161.

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Ionomers are polymers containing a small fraction of charged groups in their polymer backbone. These ionic groups link together to form ionic aggregates which act as temporary cross-links. On heating over the ionic dissociation temperature, these ionic aggregates become mobile in the melt and reaggregate upon cooling. The structure and dynamic behavior of these ionic aggregates gives rise to interesting mechanical and functional properties of the ionomers. Thermal processing of ionomers leads to secondary equilibration of these ionic aggregates. We study this phenomenon of secondary equilibration on application of a thermo-electric field where an electrostatic field is maintained over the ionomer melt. The end goal is to achieve control over the size and distribution of the ionic aggregates by means of an external electric field. The characterization techniques utilized to study the onset of secondary equilibration are UV-Vis Spectroscopy, Differential Scanning Calorimetry, Fourier Transfer Infrared Spectroscopy and Attenuated Total Reflectance analysis. The results indicate that the phenomenon of secondary equilibration is present under the application of a thermoelectric field as indicated by change in spectral and thermal data. A fundamental understanding of the secondary equilibration phenomenon and eventual prevention of the onset of secondary equilibration will lead to long term control of the ionic aggregates by means of an external electric field which will improve the function and utility of these ionomeric materials.
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Tolioe, William Amelio, Linda Hanalim, Joely Bt A Ghafar, and Thanapala Singam Murugesu. "Integrated Advance Petrophysical Evaluation for Heterolithic Clastics Reservoir Characterization Optimization in Malay Basin." In Offshore Technology Conference Asia. OTC, 2022. http://dx.doi.org/10.4043/31452-ms.

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Abstract In an oil producing S-field within Malay basin, the existence of heterolithic and thinly laminated reservoirs are common. Standard resolution logging tools are incapable to separate inter-bedded sand-shale layers due to their low vertical resolutions and the conventional petrophysical workflow was not robust enough in capturing the actual properties of the laminated sand shale (LSS) reservoirs in S-field. As a result, the estimated permeability did not match the core permeability and required a significantly high multipliers in the dynamic model and the calculated saturation failed to match the Dean-Stark saturation. This paper explains the limitation of the conventional analysis in LSS reservoir and highlights the use of PETRONAS Thin Bed Analysis (TBA) module to estimate the actual reservoir properties in S-field. The case study in this paper shows the best practice to construct the robust fieldwide evaluation of reservoir properties, integrating core to production data and advance logs information, to determine reservoir properties. In LSS reservoirs, the conventional petrophysics outputs are often pessimistic compared to core data. Reservoir Enhancement Modeling and Reservoir Fraction Modeling (REM-RFM) is an in-house PETRONAS TBA methodology for evaluating LSS reservoirs. REM-RFM workflow is designed to obtain the net sand fraction and the actual reservoir properties to describe the reservoirs storage and flow capacity. Sand-shale lamination was quantified by digital core analysis, core UV light binning against the borehole image logs. The triaxial resistivity logs were used as inputs for the Thomas-Stieber method to determine the net sand fraction and the hydrocarbon saturation. Nuclear Magnetic Resonance (NMR) data was also incorporated to confirm the hydrocarbon pore volume on well level. The REM-RFM workflow resulted in the improved reservoir properties compared to the conventional evaluation and were better matched to the core. In the laminated sands, the enhanced shale volume was comparable to the sand streaks seen in UV fluorescence core photo and image logs data, as well the enhanced porosity and permeability were matching well with the core data. Moreover, the water saturation was matching to the saturation from dean-stark core analysis result, comparable to saturation height function model and NMR data, and REM-RFM output were comparable to Thomas-Stieber results. Once the REM-RFM was calibrated in the key wells, the parameters were then applied to the whole field. The in-house REM-RFM module discussed in this paper is an excellent addition to other industry methodologies. This module is basically a continuation of the innovative effort to characterize the conventional clastic reservoirs model performed earlier. It has been proven by applying robust evaluation, the conventional outputs are significantly improved that led to the optimizes the obvious volume of hydrocarbon estimated. In addition to that, the results can be used for reducing the risks in monetizing the opportunities from the heterolithics and laminated sands.
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Zanini, F. "ARCHAEOLOGICAL APPLICATIONS OF SYNCHROTRON RADIATION AT ELETTRA." In Знаки и образы в искусстве каменного века. Международная конференция. Тезисы докладов [Электронный ресурс]. Crossref, 2019. http://dx.doi.org/10.25681/iaras.2019.978-5-94375-308-4.33.

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The use of synchrotron radiation for the analysis of samples of historical and artistic importance (archaeology, palaeontology, conservation sciences, palaeo-environments) has been increasing over the past years, and experiments related to the study of our cultural heritage (CH) have been routinely performed at many beamlines of Elettra, the Italian synchrotron radiation facility. Fundamental parameters such as the high photon flux, the small source size and the low divergence typical of synchrotrons make it a very efficient source for a range of advanced spectroscopy and imaging techniques, adapted to the dishomogeneity and complexity of the materials under study. The continuous tunability of the source (from infrared to X-rays) is essential for techniques based on a fine tuning of the probing energy to reach high chemical sensitivity such as XANES, EXAFS, STXM, UV/VIS spectrometry. Moreover, the small source size attained in the vertical plane leads to spatial coherence of the photon source itself, giving rise to a series of imaging methods already crucial to the field. The increasing number of scientific publications shows that microfocused hard X-ray spectroscopy (absorption, fluorescence, diffraction), full-field X-ray tomography and infrared spectroscopy are the most popular synchrotron techniques in the field. The Elettra laboratory now offers a platform dedicated to CH researchers in order to support both the proposal application phase and the different steps of the experiment, from sample preparation to data analysis. We will present this activity and the main instrumental setups and experimental techniques in use at Elettra, and describe their impact for the science being applied to ancient materials using synchrotron rad
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Reports on the topic "UV risk analysis"

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Crouch, Rebecca, Jared Smith, Bobbi Stromer, Christian Hubley, Samuel Beal, Guilherme Lotufo, Afrachanna Butler, et al. Preparative, extraction, and analytical methods for simultaneous determination of legacy and insensitive munition (IM) constituents in aqueous, soil or sediment, and tissue matrices. Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41480.

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No standard method exists for determining levels of insensitive munition (IM) compounds in environmental matrices. This project resulted in new methods of extraction, analytical separation and quantitation of 17 legacy and 7 IM compounds, daughter products of IM, and other munition compounds absent from USEPA Method 8330B. Extraction methods were developed for aqueous (direct-injection and solid-phase extraction [SPE]), soil, sediment, and tissue samples using laboratory-spiked samples. Aqueous methods were tested on 5 water sources, with 23 of 24 compounds recovered within DoD QSM Ver5.2 limits. New solvent extraction (SE) methods enabled recovery of all 24 compounds from 6 soils within QSM limits, and a majority of the 24 compounds were recovered at acceptable levels from 4 tissues types. A modified chromatographic treatment method removed analytical interferences from tissue extracts. Two orthogonal high-performance liquid chromatography-ultraviolet (HPLC-UV) separation methods, along with an HPLC–mass spectrometric (HPLC-MS) method, were developed. Implementing these new methods should reduce labor and supply costs by approximately 50%, requiring a single extraction and sample preparation, and 2 analyses rather than 4. These new methods will support environmental monitoring of IM and facilitate execution of risk-related studies to determine long-term effects of IM compounds.
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Borch, Thomas, Yitzhak Hadar, and Tamara Polubesova. Environmental fate of antiepileptic drugs and their metabolites: Biodegradation, complexation, and photodegradation. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597927.bard.

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Many pharmaceutical compounds are active at very low doses, and a portion of them regularly enters municipal sewage systems and wastewater-treatment plants following use, where they often do not fully degrade. Two such compounds, CBZ and LTG, have been detected in wastewater effluents, surface waters, drinking water, and irrigation water, where they pose a risk to the environment and the food supply. These compounds are expected to interact with organic matter in the environment, but little is known about the effect of such interactions on their environmental fate and transport. The original objectives of our research, as defined in the approved proposal, were to: Determine the rates, mechanisms and products of photodegradation of LTG, CBZ and selected metabolites in waters exposed to near UV light, and the influence of DOM type and binding processes on photodegradation. Determine the potential and pathways for biodegradation of LTG, CBZ and selected metabolites using a white rot fungus (Pleurotusostreatus) and ADP, and reveal the effect of DOM complexation on these processes. Reveal the major mechanisms of binding of LTG, CBZ and selected metabolites to DOM and soil in the presence of DOM, and evaluate the effect of this binding on their photodegradation and/or biodegradation. We determined that LTG undergoes relatively slow photodegradation when exposed to UV light, and that pH affects each of LTG’s ability to absorb UV light, the efficiency of the resulting reaction, and the identities of LTG’sphotoproducts (t½ = 230 to 500 h during summer at latitude 40 °N). We observed that LTG’sphotodegradation is enhanced in the presence of DOM, and hypothesized that LTG undergoes direct reactions with DOM components through nucleophilic substitution reactions. In combination, these data suggest that LTG’s fate and transport in surface waters are controlled by environmental conditions that vary with time and location, potentially affecting the environment and irrigation waters. We determined that P. ostreatusgrows faster in a rich liquid medium (glucose peptone) than on a natural lignocellulosic substrate (cotton stalks) under SSF conditions, but that the overall CBZ removal rate was similar in both media. Different and more varied transformation products formed in the solid state culture, and we hypothesized that CBZ degradation would proceed further when P. ostreatusand the ᵉⁿᶻʸᵐᵃᵗⁱᶜ ᵖʳᵒᶠⁱˡᵉ ʷᵉʳᵉ ᵗᵘⁿᵉᵈ ᵗᵒ ˡⁱᵍⁿⁱⁿ ᵈᵉᵍʳᵃᵈᵃᵗⁱᵒⁿ. ᵂᵉ ᵒᵇˢᵉʳᵛᵉᵈ ¹⁴C⁻Cᴼ2 ʳᵉˡᵉᵃˢᵉ ʷʰᵉⁿ ¹⁴C⁻ᶜᵃʳᵇᵒⁿʸˡ⁻ labeled CBZ was used as the substrate in the solid state culture (17.4% of the initial radioactivity after 63 days of incubation), but could not conclude that mineralization had occurred. In comparison, we determined that LTG does not degrade in agricultural soils irrigated with treated wastewater, but that P. ostreatusremoves up to 70% of LTG in a glucose peptone medium. We detected various metabolites, including N-oxides and glycosides, but are still working to determine the degradation pathway. In combination, these data suggest that P. ostreatuscould be an innovative and effective tool for CBZ and LTG remediation in the environment and in wastewater used for irrigation. In batch experiments, we determined that the sorption of LTG, CBZ and selected metabolites to agricultural soils was governed mainly by SOM levels. In lysimeter experiments, we also observed LTG and CBZ accumulation in top soil layers enriched with organic matter. However, we detected CBZ and one of its metabolites in rain-fed wheat previously irrigated with treated wastewater, suggesting that their sorption was reversible, and indicating the potential for plant uptake and leaching. Finally, we used macroscale analyses (including adsorption/desorption trials and resin-based separations) with molecular- level characterization by FT-ICR MS to demonstrate the adsorptive fractionation of DOM from composted biosolids by mineral soil. This suggests that changes in soil and organic matter types will influence the extent of LTG and CBZ sorption to agricultural soils, as well as the potential for plant uptake and leaching.
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