178 research outputs found

    IR Barcode Reader

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    BrandWatch Technologies is a company based in Portland, Oregon that seek to detect counterfeit products in the supply chain. BrandWatch has created a taggant material, a physical marker, that can be printed over barcodes or added to the ink used to print the barcodes themselves. This material, while invisible to the naked eye, is detectable using technology that they have developed. BrandWatch enlisted the help of a four man team of Cal Poly Mechanical Engineering students to combine this technology with that of a barcode scanner. The device, capable of scanning barcodes, detecting the presence of the taggant material, and relaying this information to the user is the end result of this project. The device is easily modifiable to request a taggant read or barcode scan first. A user simply has to pull the trigger and is walked through the process of scanning and reading via LCD screen prompts on the back of the handheld device. The data collected (both barcode and the presence of the taggant) is stored in a csv file on a small USB drive on the back of the device. This can easily be removed to transfer the data to a computer at the end of a work day

    Biosecurity Practices Applied in Aquacultural Farms in Northern Senegal,West Africa

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    This study was conducted in northern Senegal, covering the regions of Saint-Louis, Louga and Matam, from June 2016 to December 2016. Surveys were carried out at all farms in this area where fish, shrimp, and molluscs farming or grow-out activities are conducted. The sampling method used is the survey determined by respondents which is a variation of snowball sampling. This method allowed us to administer a questionnaire to the fiftynine farms in activity in northern Senegal. The overall objective of this paper is to contribute to the improvement of knowledge on aquaculture biosecurity in the study areas through the application of biosecurity measures. This study highlighted the interconnections between the different farms, identified biosecurity measures for infrastructure, livestock and food, and assessed the different biosecurity measures applied to staff. The results revealed that biosecurity measures are poorly implemented. 74.6% of the people surveyed are also unaware of the mechanisms by which aquatic animal diseases appear and spread out, while 86.4% of them have no knowledge of biosecurity in aquaculture. Our recommendations focus on the need to encourage aquaculture professionals to apply biosecurity measures at all production stages. There is also the need for training or capacity building for aquaculture farmers on biosecurity measures. &nbsp

    Antimicrobial activity of spherical silver nanoparticles prepared using a biocompatible macromolecular capping agent: evidence for induction of a greatly prolonged bacterial lag phase

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    <p>Abstract</p> <p>Background</p> <p>We have evaluated the antimicrobial properties of Ag-based nanoparticles (<it>Np</it>s) using two solid phase bioassays and found that 10-20 μL of 0.3-3 μM keratin-stabilized <it>Np</it>s (depending on the starting bacterial concentration = <it>C</it><sub>I</sub>) completely inhibited the growth of an equivalent volume of <it>ca</it>. 10<sup>3 </sup>to 10<sup>4 </sup>colony forming units per mL (CFU mL<sup>-1</sup>) <it>Staphylococcus aureus</it>, <it>Salmonella </it>Typhimurium, or <it>Escherichia coli </it>O157:H7 on solid surfaces. Even after one week at 37°C on solid media, no growth was observed. At lower <it>Np </it>concentrations (= [<it>Np</it>]s), visible colonies were observed but they eventually ceased growing.</p> <p>Results</p> <p>To further study the physiology of this growth inhibition, we repeated these experiments in liquid phase by observing microbial growth via optical density at 590 nm (OD) at 37°C in the presence of a [<it>Np</it>] = 0 to 10<sup>-6 </sup>M. To extract various growth parameters we fit all OD[t] data to a common sigmoidal function which provides measures of the beginning and final OD values, a first-order rate constant (<it>k</it>), as well as the time to calculated 1/2-maximal OD (<it>t</it><sub>m</sub>) which is a function of <it>C</it><sub>I</sub>, <it>k</it>, as well as the microbiological lag time (<it>T</it>).</p> <p>Performing such experiments using a 96-well microtitre plate reader, we found that growth <it>always </it>occurred in solution but <it>t</it><sub>m </sub>varied between 7 (controls; <it>C</it><sub>I </sub>= 8 × 10<sup>3 </sup>CFU mL<sup>-1</sup>) and > 20 hrs using either the citrate-([<it>Np</it>] ~ 3 × 10<sup>-7 </sup>M) or keratin-based ([<it>Np</it>] ~ 10<sup>-6 </sup>M) <it>Np</it>s and observed that {∂<it>t</it><sub>m</sub>/∂ [<it>Np</it>]}<sub>citrate </sub>~ 5 × 10<sup>7 </sup>and {∂<it>t</it><sub>m</sub>/∂ [<it>Np</it>]}<sub>keratin </sub>~ 10<sup>7 </sup>hr·L mol<sup>-1</sup>. We also found that there was little effect of <it>Np</it>s on <it>S. aureus </it>growth rates which varied only between <it>k </it>= 1.0 and 1.2 hr<sup>-1 </sup>(1.1 ± 0.075 hr<sup>-1</sup>). To test the idea that the <it>Np</it>s were changing the initial concentration (<it>C</it><sub>I</sub>) of bacteria (<it>i.e</it>., cell death), we performed probabilistic calculations assuming that the perturbations in <it>t</it><sub>m </sub>were due to <it>C</it><sub>I </sub>alone. We found that such large perturbations in <it>t</it><sub>m </sub>could only come about at a <it>C</it><sub>I </sub>where the probability of any growth at all was small. This result indicates that much of the <it>Np</it>-induced change in <it>t</it><sub>m </sub>was due to a greatly increased <it>T </it>(<it>e.g</it>., from <it>ca</it>. 1 to 15-20 hrs). For the solid phase assays we hypothesize that the bacteria eventually became non-culturable since they were inhibited from undergoing further cell division (<it>T </it>> many days).</p> <p>Conclusion</p> <p>We propose that the difference between the solid and liquid system relates to the obvious difference in the exposure, or residence, time of the <it>Np</it>s with respect to the bacterial cell membrane inasmuch as when small, <it>Np</it>-inhibited colonies were selected and streaked on fresh (<it>i.e</it>., no <it>Np</it>s present) media, growth proceeded normally: <it>e.g</it>., a small, growth-inhibited colony resulted in a plateful of typical <it>S. aureus </it>colonies when streaked on fresh, solid media.</p

    The SynergEyes hybrid contact lens fitting guide and information

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    Historically, creating a lens with the optics of a rigid contact lens and the comfort of a soft contact lens has been fraught with difficulty. New technology, however has enabled us to create a hybrid lens that would greatly benefit people who suffer from corneal problems that prevent them from using conventional contact lenses. This paper describes a fitting guide for the new SynergEyes A hybrid contact lens based on a two part series of on-eye fitting trials

    Use of experimental sensors for discrimination of artificial breath mixtures in a lung cancer screening context

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    peer reviewedThe Pathacov project [3] aims at creating an electronic nose to detect lung cancer in the population at risk. Metal oxide sensors are being developed within the project to better detect cancer biomarkers, which are identified within a large-scale clinical study in university hospitals in the north-east of France. Before long and costly clinical trials, the performance of the prototype electronic nose has to be evaluated. In order to do this, a novel approach has been implemented. Real breath samples from healthy and available volunteers are collected in Teflon FEP sampling bags. The results of the electronic nose are processed through a principal component analysis (PCA) in order to evaluate the contribution of each sensor to the separation of the group’s clusters (healthy and cancer). This enables the selection of the best performing sensors to be included in the final prototype.Pathaco

    Advanced cotton fibers exhibit efficient photocatalytic self-cleaning and antimicrobial activity

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    Functional cotton fibers have a wide range of applications in domestic, commercial, and military settings, and so enhancing the properties of these materials can yield substantial benefits. Herein, we report the creation of functional fibers that are self-cleaning, anti-microbial, and protective against UV radiation. A uniform, and high surface area films of TiO2 were deposited on cotton fibers and gold/silver nanoparticles were directly incorporated on the nanostructured TiO2 surface. The synthetic method is simple and the produced TiO2 film is homogenous and the nanoparticles were shown to be effectively distributed on the surface using a simple photocatalytic reduction method. The Ag/Au-TiO2 coated fibers was morphologically characterized using atomic force microscopy (AFM) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), and the self-cleaning properties of noble metal nanoparticle/TiO2 coated fibers were demonstrated by repeated staining followed by exposure to simulated solar light. The 1 mM Ag-TiO2 coated fabric was observed to have the largest improvement in rate of stain extinction compared to the untreated fibers with a methylene blue stain, and the 1 mM Au-TiO2 coated fibers were observed to have the largest improvement versus untreated fibers when stained with Congo red. The fibers maintained consistent photocatalytic activity over multiple cycles, and the resistance of the Ag/Au-TiO2 coated cotton to degradation was verified using Fourier transform infrared spectroscopy (FTIR). An efficient anti-microbial activity of the fibers was confirmed by exposure of the fibers to bacterial culture (Escherichia Coli) and direct observation of antimicrobial activity

    Bayesian Learning of Gas Transport in Three-Dimensional Fracture Networks

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    Modeling gas flow through fractures of subsurface rock is a particularly challenging problem because of the heterogeneous nature of the material. High-fidelity simulations using discrete fracture network (DFN) models are one methodology for predicting gas particle breakthrough times at the surface, but are computationally demanding. We propose a Bayesian machine learning method that serves as an efficient surrogate model, or emulator, for these three-dimensional DFN simulations. Our model trains on a small quantity of simulation data and, using a graph/path-based decomposition of the fracture network, rapidly predicts quantiles of the breakthrough time distribution. The approach, based on Gaussian Process Regression (GPR), outputs predictions that are within 20-30% of high-fidelity DFN simulation results. Unlike previously proposed methods, it also provides uncertainty quantification, outputting confidence intervals that are essential given the uncertainty inherent in subsurface modeling. Our trained model runs within a fraction of a second, which is considerably faster than other methods with comparable accuracy and multiple orders of magnitude faster than high-fidelity simulations

    Development of an intervention to support reproductive health of garment factory workers in Cambodia: a qualitative study.

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    OBJECTIVES: The aim of this study was to describe the development of an intervention to support the reproductive health of garment factory workers in Cambodia. DESIGN: A qualitative study informed by intervention mapping which included semistructured interviews and participant observation, followed by intervention development activities including specifying possible behaviour change, designing the intervention, and producing and refining intervention content. SETTING: The research was conducted by a multidisciplinary team with backgrounds in public health, linguistics, digital cultures and service delivery in a suburb of Phnom Penh where many garment factories cluster. PARTICIPANTS: Garment factory workers in Cambodia; typically young women aged under 30 years who have migrated from rural areas to Phnom Penh city. OUTCOMES: Analysis of reproductive health issues facing garment factory workers and metrics of videos developed. RESULTS: Our research identified some challenges that Cambodian garment factory workers experience regarding contraception and abortion. Concerns or experience of side-effects were identified as an important determinant leading to non-use of effective contraception and subsequent unintended pregnancy. Financial constraints and a desire to space pregnancies were the main reported reasons to seek an abortion. Information about medical abortion given to women by private providers was often verbal, with packaging and the drug information leaflet withheld. In order to address limitations in the provision of accessible reproductive health information for factory workers, and given their observed widespread use of social media, we decided to make three 'edutainment' videos about family planning. Key social media metrics of the videos were evaluated after 1 month. CONCLUSIONS: We describe the development of an intervention to support reproductive health among garment factory workers in Cambodia. These videos could be further improved and additional videos could be developed. More work is required to develop appropriate and effective interventions to support reproductive health of garment factory workers in Cambodia
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