scholarly journals Analysis of the influence of UV light exposure time on hardness and density properties of SLA models

2020 ◽  
Author(s):  
Łukasz Dzadz ◽  
Bartosz Pszczółkowski

The article analysis the effect of exposure to ultraviolet light on the hardening process of the model made in the SLA technology. Research samples were created with the SLA additive technique using a 10s exposure time. In this experiment, the change in item hardness and density over a 96-hour period was analysed. Light exposure time for details of an item made in SLA technology results in an increase in hardness. At the same time are observed, changes in density and stabilization of both parameters with increasing exposure time to UV light. .

2016 ◽  
Vol 1133 ◽  
pp. 399-403
Author(s):  
Nurul Najua Zulkepely ◽  
Siti Nurasiah Mat Nawi ◽  
Norfadira Wahib ◽  
Yusoff Mohd Amin ◽  
Roslan Md Nor ◽  
...  

In this paper we report, the characteristics of PTTL after irradiation with 60Co gamma rays as a function UV light exposure wavelength, gamma irradiation dose, and UV light exposure time were determined for Ge-doped SiO2 optical fibers. The efficiency of dose reassessment for this fiber was compared to standard thermoluminescence detector, TLD100. Experiments show that the method works well with the UV lamp of 254 nm within region of doses between 3 to 50 Gy, but could be applied for higher and lower doses as well. The effect of exposure time of UV radiation on the PTTL signal was studied from 5 to 120 minutes to determine the highest sensitivity and the limit of the dose. The efficiency of dose reassessment with 10 Gy of gamma irradiation expose to UV light for 15 minutes relative to PTTL values of about 27.0% and 2.3% for Ge-doped SiO2 optical fiber and TLD100.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sean Swetledge ◽  
Renee Carter ◽  
Rhett Stout ◽  
Carlos E. Astete ◽  
Jangwook P. Jung ◽  
...  

AbstractPolymeric nanoparticles have been investigated as potential delivery systems for therapeutic compounds to address many ailments including eye disease. The stability and spatiotemporal distribution of polymeric nanoparticles in the eye are important regarding the practical applicability and efficacy of the delivery system in treating eye disease. We selected poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with lutein, a carotenoid antioxidant associated with eye health, as our model ophthalmic nanodelivery system and evaluated its stability when suspended in various conditions involving temperature and light exposure. We also assessed the ocular biodistribution of the fluorescently labeled nanoparticle vehicle when administered topically. Lutein-loaded nanoparticles were stable in suspension when stored at 4 °C with only 26% lutein release and no significant lutein decay or changes in nanoparticle morphology. When stored at 25 °C and 37 °C, these NPs showed signs of bulk degradation, had significant lutein decay compared to 4 °C, and released over 40% lutein after 5 weeks in suspension. Lutein-loaded nanoparticles were also more resistant to photodegradation compared to free lutein when exposed to ultraviolet (UV) light, decaying approximately 5 times slower. When applied topically in vivo, Cy5-labled nanoparticles showed high uptake in exterior eye tissues including the cornea, episcleral tissue, and sclera. The choroid was the only inner eye tissue that was significantly higher than the control group. Decreased fluorescence in all exterior eye tissues and the choroid at 1 h compared to 30 min indicated rapid elimination of nanoparticles from the eye.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A843-A843
Author(s):  
Michael Wagner ◽  
Megan Othus ◽  
Sandip Patel ◽  
Christopher Ryan ◽  
Ashish Sangal ◽  
...  

BackgroundAngiosarcoma is a rare cancer of endothelial cells that can be aggressive and carries a high mortality. A subset of angiosarcomas are characterized by high tumor mutational burden (TMB) and UV light exposure DNA mutational signature. Isolated case reports have suggested clinical efficacy of immune checkpoint blockade in angiosarcoma; no prospective studies of immune checkpoint inhibition in angiosarcoma have been reported. We report efficacy analysis results for patients with advanced or unresectable angiosarcoma treated with ipilimumab and nivolumab as a cohort of an ongoing phase II study for rare cancers (NCT02834013).MethodsThis is a prospective, open-label, multicenter phase II clinical trial of ipilimumab (1mg/kg IV q6weeks) plus nivolumab (240mg IV q2weeks) for patients with metastatic or unresectable angiosarcoma. Primary endpoint is objective response rate as assessed by RECIST v1.1, including measurable cutaneous disease that can be followed by photography. Secondary endpoints include PFS, OS, stable disease at six months, and toxicity. A two-stage design is used with six patients in the first stage and an additional ten patients in the second stage.ResultsAt data cutoff, 16 patients with angiosarcoma were enrolled. Median age was 68 years (25-81 years). Median number of prior lines of therapy was 2 (0-5). 9 patients had cutaneous primary tumors of any cutaneous site, 7 had non-cutaneous primary tumors. ORR for all patients was 25% (4/16, table 1, figure 1). Subgroup analysis revealed that 60% (3/5) of patients with primary cutaneous tumors of the scalp or face had a confirmed objective response. 6-month PFS was 38%. 75% of patients experienced an adverse event (AE), and 25% experienced a grade 3-4 AE. 68.8% experienced an immune related AE (irAE), and 2 (12.5%) developed grade 3 or 4 irAEs. Grade 3-4 irAEs were ALT and AST increase and diarrhea. There were no grade 5 toxicities.ConclusionsThe combination of ipilimumab and nivolumab was well tolerated and had an ORR of 25% in angiosarcoma regardless of primary site, with 3 of 5 patients with cutaneous tumors of the scalp or face responding. Ipilimumab and nivolumab warrant further investigation in angiosarcoma.AcknowledgementsFunding: National Institutes of Health/National Cancer Institute grant awards CA180888, CA180819, CA180868; and in part by Bristol-Myers Squibb CompanyTrial RegistrationNCT02834013Ethics ApprovalThis study was approved by the NCI CIRB.


2020 ◽  
Vol 44 (19) ◽  
pp. 7749-7757 ◽  
Author(s):  
Wen Jia ◽  
Dong Peng ◽  
Zijuan Feng ◽  
Xue Wu ◽  
Yi Liu ◽  
...  

Concomitant formation of metallic Bi nanoparticles and oxygen vacancies was successfully achieved within Bi/BiOBr/RGO composites by green UV-light exposure.


Planta ◽  
2003 ◽  
Vol 217 (3) ◽  
pp. 457-465 ◽  
Author(s):  
Tanja Marwedel ◽  
Toyotaka Ishibashi ◽  
Ren� Lorbiecke ◽  
Silke Jacob ◽  
Kengo Sakaguchi ◽  
...  

2018 ◽  
Vol 156 ◽  
pp. 08003 ◽  
Author(s):  
Tutuk Djoko Kusworo ◽  
Danny Soetrisnanto ◽  
Cynthia Santoso ◽  
Tyas Dwi Payanti ◽  
Dani Puji Utomo

Produced water is a wastewater generated from petroleum industry with high concentration of pollutants such as Total Dissolved Solid, Organic content, and Oil and grease. Membrane technology has been currently applied for produced water treatment due to its efficiency, compact, mild and clean process. The main problem of produced water using membrane is fouling on the membrane surface which causes on low permeate productivity. This paper is majority focused on the improvement of anti-fouling performance through several modifications to increase CA membrane hydrophilicity. The membrane was prepared by formulating the dope solution consists of 18 wt-% CA polymer, acetone, and PEG additive (3 wt-%, 5 wt-%, and 7 wt-%). The membranes are casted using NIPS method and being irradiated under UV light exposure. The SEM images show that parepared membrane has asymmetric structure consist of dense layer, intermediete layer, and finger-like support layer. The filtration test shows that PEG addition increase the membrane hydrophilicity and the permeate flux increases. UV light exposure on the membrane improves the membrane stability and hydrophilicity. The imrpovement of membrane anti-fouling performance is essential to achieve the higher productivity without lowering its pollutants rejection.


1995 ◽  
Vol 74 (5) ◽  
pp. 493-498 ◽  
Author(s):  
Mark W. Beatty ◽  
Gordon K. Mahanna ◽  
Kurt Dick ◽  
Wenyi Jia

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