Asphalt Crack Treatment FAQs and Technical Resources

Crack treatment is one of the most used pavement preservation practices and although the technique is simple, there are several nuances that make it more of an art than science. The purpose of this document is to provide: \u2022 An overview of crack treatment, \u2022 Guidance on several FAQs, and \u2022 A high-level summary of several technical resources. Crack sealing is an important preventive treatment in a pavement preservation program to extend a pavement\u2019s serviceable life. Many factors go into determining \u201cif\u201d and \u201chow to\u201d best implement a crack treatment program. The following information is a compilation of synthesizing several technical documents and interviews with some local technical/industry representatives. Although much of this information is research based, some is anecdotal and/or advice from experienced practitioners. The intent is to provide an overview so agencies can draw their own conclusions on how to best implement a crack treatment program

Pratos e mais pratos: louças domésticas, divisões culturais e limites sociais no Rio de Janeiro, século XIX

Reply to ten comments on a paper published in the last issue of this journal. The discussion follows along six main lines: History museums, identity, ideology and the category of nation; the need of material collections and their modalities: patrimonial, operational, virtual; theater versus laboratory; visitors and their ambiguities; Public History: the museum and the academy.Resposta aos comentários de dez especialistas que contribuíram no debate de texto publicado no último número desta revista. A discussão orientou-se segundo seis tópicos principais: museus históricos, identidade, ideologia e a categoria de nação; a necessidade de acervos materiais e suas modalidades: acervo patrimonial, operacional, virtual; teatro versus laboratório; o público e suas ambigüidades; História Pública: o museu e a Academia

Strain sensing using colloidal quantum dots integrated with epoxy

A colloidal quantum dot loaded polymer coated onto the surface of a sample pre-coated with epoxy was found to linearly change photoluminescence intensity around a 611.5 nm peak while under tensile strain. This peak was the epoxy’s photoluminescence emission wavelength while the wavelengths around it were attributed to the colloidal quantum dot loaded polymer. From the spectra emitted from both the epoxy and the colloidal quantum dot loaded polymer, an empirical relation was made to calculate the changes in photoluminescence intensity between them. A calibration was then devised to create an optical stress-strain curve. The relationship found between both the optical and mechanical stress-strain curves indicated that this measurement technique followed the sample towards failure in the plastic region better than when only measuring from a colloidal quantum dot loaded polymer peak. For the first time, the results demonstrated here show that an epoxy’s photoluminescence emission peak utilized in tandem with colloidal quantum dot loaded polymer can be used for strain sensing. Potential applications that could benefit from this finding would be: quality control, strain gauge for systems, and materials science

Comprehensive optical strain sensing through the use of colloidal quantum dots

The adaptation of colloidal quantum dots loaded within a polymer for use in nondestructive testing can be used as an optical strain gauge due to the nanomaterial’s strain sensing properties. In this paper, we utilized InP/ZnS colloidal quantum dots loaded within a polymer matrix applied onto the surface of a dog-bone foil pre-coated with an epoxy. By employing an empirical formula and a calibration factor, there is a propinquity between both the calculated optical strain and mechanical stress-strain reference data. Fluctuations are observed which may be due to both additional strain responses not seen by the mechanical data and quantum dot blinking. These results and methods show applied use of this novel optical non-destructive testing technique for a variety of structures, especially for structures which operate in harsh environments

Comprehensive Optical Strain Sensing Through the Use of Colloidal Quantum Dots

The adaptation of colloidal quantum dots loaded within a polymer for use in nondestructive testing can be used as an optical strain gauge due to the nanomaterial’s strain sensing properties. In this paper, we utilized InP/ZnS colloidal quantum dots loaded within a polymer matrix applied onto the surface of a dog-bone foil pre-coated with an epoxy. By employing an empirical formula and a calibration factor, there is a propinquity between both the calculated optical strain and mechanical stress-strain reference data. Fluctuations are observed which may be due to both additional strain responses not seen by the mechanical data and quantum dot blinking. These results and methods show applied use of this novel optical non-destructive testing technique for a variety of structures, especially for structures which operate in harsh environments

Urinary fistula after robot-assisted partial nephrectomy: a multicentre analysis of 1 791 patients.

OBJECTIVE: To evaluate the incidence of and risk factors for a urine leak in a large multicentre, prospective database of robot-assisted partial nephrectomy (RPN). PATIENTS AND METHODS: A database of 1 791 RPN from five USA centres was reviewed for urine leak as a complication of RPN. Patient and tumour characteristics were compared between patients with and those without postoperative urine leaks. Fisher\u27s exact test was used for qualitative variables and Wilcoxon sum-rank tests were used for quantitative variables. A review of the literature on PN and urine leak was conducted. RESULTS: Urine leak was noted in 14/1 791 (0.78%) patients who underwent RPN. The mean (sd) nephrometry score of the entire cohort was 7.2 (1.9), and 8.0 (1.9) in patients who developed urine leak. The median (range) postoperative day of presentation was 13 (3-32) days. Patients with urine leak presented in delayed fashion with fever (two of the 14 patients, 14%), gastrointestinal complaints (four patients, 29%), and pain (five patients, 36%). Eight of the 14 patients (57%) required admission, while eight (57%) and nine (64%) had a drain or stent placed, respectively. Drains and stents were removed after a median (range) of 8 (4-13) days and 21 (8-83) days, respectively. Variables associated with urine leak included tumour size (P = 0.021), hilar location (P = 0.025), operative time (P = 0.006), warm ischaemia time (P = 0.005), and pelvicalyceal repair (P = 0.018). Upon literature review, the historical incidence of urine leak ranged from 1.0% to 17.4% for open PN and 1.6-16.5% for laparoscopic PN. CONCLUSION: The incidence of urine leak after RPN is very low and may be predicted by some preoperative factors, affording better patient counselling of risks. The low urinary leak rate may be attributed to the enhanced visualisation and suturing technique that accompanies the robotic approach