47 research outputs found

    Review of Clinical Features, Microbiological Spectrum, and Treatment Outcomes of Endogenous Endophthalmitis over an 8-Year Period

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    Purpose. To evaluate the clinical features, microbiological spectrum, and treatment outcomes of endogenous endophthalmitis. Methods. Retrospective review of consecutive cases with infective endogenous endophthalmitis presenting from 2000 to 2007. The main outcome measure was the visual outcome at the latest follow-up visit. Other outcome measures included microbiological investigations, anatomical and clinical outcomes. Results. 22 eyes of 21 patients were included, and the mean follow-up duration was 2.7 years. Eyes with fungal endogenous endophthalmitis were more likely to have visual acuity of finger counting or better at presentation compared with those with bacterial endogenous endophthalmitis (odds ratio=15.0, =0.013). Gram-negative microorganisms accounted for 50% of infections, while fungal and gram-positive organisms accounted for 27.3% and 22.7%, respectively. Despite treatment, the visual outcome was poor in general as 10 (45.5%) eyes had no light perception at the latest follow-up visit and 6 (27.3%) eyes required enucleation or evisceration. Contrary to previous studies, fungal endogenous endophthalmitis did not appear to have better visual outcome compared with bacterial endogenous endophthalmitis. Conclusion. Gram-negative microorganisms were the main causative pathogens of endogenous endophthalmitis in Hong Kong. The visual prognosis of endogenous endophthalmitis is generally poor as almost 50% of eyes were blind despite treatment

    Reaping the benefits of digitisation:Pilot study exploring revenue generation from digitised collections through technological Innovation

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    In the last decade significant resources have been invested for the digitisation of the collections of a large number of museums and galleries worldwide. In Europe alone, 10 million EUR is annually invested in Europeana (Europeana 2014). However, as we gradually move on from “the start-up phase” of digitisation (Hughes 2004), revenue generation and sustainability must be considered (Hughes 2004). Even beyond digitisation, generating revenue through innovation and in particular “finding new business models to sustain funding” (Simon 2011) ranks amongst museums’ top challenges (Simon 2011). More importantly, despite the significant wealth of digitised assets museums now own, little has been done to investigate ways these institutions could financially benefit from their digitised collections. For art institutions in particular, this has been largely limited to the sale of image licenses, with the fear of losing this revenue posing as one of the key reasons art museums are reluctant to join the Open Content movement (Kapsalis 2016). This paper examines how recent technological advancements, such as image recognition and Print-on-Demand automation, can be utilised to take advantage of the wealth of digitised artworks museums and galleries have in their possession. A pilot study of the proposed solution at the State Museum of Contemporary Art (SMCA) in Thessaloniki, Greece, is covered and the findings are examined. Early feedback indicates that there is a significant potential in the utilisation of the aforementioned technologies for the monetisation of digitised collections. However, challenges such as blending the real-world experience with the digital experience, as well as flattening the learning curve of the technological solution for museum visitors, need to be addressed. Based on the pilot study at SMCA, this paper investigates how emerging technologies can be utilised to facilitate revenue generation for all museums and galleries with digitised collections

    Operating Hydrogen-Based Energy Storage Systems in Wind Farms for Smooth Power Injection: A Penalty Fees Aware Model Predictive Control

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    Smooth power injection is one of the possible services that modern wind farms could provide in the not-so-far future, for which energy storage is required. Indeed, this is one among the three possible operations identified by the International Energy Agency (IEA)-Hydrogen Implementing Agreement (HIA) within the Task 24 final report, that may promote their integration into the main grid, in particular when paired to hydrogen-based energy storages. In general, energy storage can mitigate the inherent unpredictability of wind generation, providing that they are deployed with appropriate control algorithms. On the contrary, in the case of no storage, wind farm operations would be strongly affected, as well as their economic performances since the penalty fees wind farm owners/operators incur in case of mismatches between the contracted power and that actually delivered. This paper proposes a Model Predictive Control (MPC) algorithm that operates a Hydrogen-based Energy Storage System (HESS), consisting of one electrolyzer, one fuel cell and one tank, paired to a wind farm committed to smooth power injection into the grid. The MPC relies on Mixed-Logic Dynamic (MLD) models of the electrolyzer and the fuel cell in order to leverage their advanced features and handles appropriate cost functions in order to account for the operating costs, the potential value of hydrogen as a fuel and the penalty fee mechanism that may negatively affect the expected profits generated by the injection of smooth power. Numerical simulations are conducted by considering wind generation profiles from a real wind farm in the center-south of Italy and spot prices according to the corresponding market zone. The results show the impact of each cost term on the performances of the controller and how they can be effectively combined in order to achieve some reasonable trade-off. In particular, it is highlighted that a static choice of the corresponding weights can lead to not very effective handling of the effects given by the combination of the system conditions with the various exogenous’, while a dynamic choice may suit the purpose instead. Moreover, the simulations show that the developed models and the set-up mathematical program can be fruitfully leveraged for inferring indications on the devices’ sizing

    Proton exchange membrane fuel cell modules for ship applications

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    In this article, we proposed a more reliable architecture composed of five fuel cell modules (FC), a storage system composed of battery and supercapacitor was also proposed to support the operation of the fuel cell. The main objective of this work is to study the feasibility of using the global system for small marine applications. In this paper, the global system was modeled and then simulated using Matlab/Simulink. The fuel cell is used as the main power source; each fuel cell is connected with a DC bus via a DC–DC boost converter. The Energy Storage System (HESS) is controlled as a fast-bidirectional auxiliary power source, it contains a battery and supercapacitors and each source is connected to the DC bus via a bidirectional buck-boost DC–DC converter (BBDCC). In order to optimize the HESS, the supercapacitors and the batteries are designed to allow high-efficiency operation and minimal weight. The entire system’s energy management algorithm (PMA) is developed to satisfy the energy demand of the boat. Finally, simulation tests are presented in Matlab/Simulink and discussed, where the effectiveness of the proposed system with its control is confirmed.N/

    The Isorhamnetin-Containing Fraction of Philippine Honey Produced by the Stingless Bee Tetragonula biroi Is an Antibiotic against Multidrug-Resistant Staphylococcus aureus

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    Honey exhibits antibacterial and antioxidant activities that are ascribed to its diverse secondary metabolites. In the Philippines, the antibacterial and antioxidant activities, as well as the bioactive metabolite contents of the honey, have not been thoroughly described. In this report, we investigated the in vitro antibacterial and antioxidant activities of honey from Apis mellifera and Tetragonula biroi, identified the compound responsible for the antibacterial activity, and compared the observed bioactivities and metabolite profiles to that of Manuka honey, which is recognized for its antibacterial and antioxidant properties. The secondary metabolite contents of honey were extracted using a nonionic polymeric resin followed by antibacterial and antioxidant assays, and then spectroscopic analyses of the phenolic and flavonoid contents. Results showed that honey extracts produced by T. biroi exhibits antibiotic activity against Staphylococcal pathogens as well as high antioxidant activity, which are correlated to its high flavonoid and phenolic content as compared to honey produced by A. mellifera. The bioassay-guided fractionation paired with Liquid Chromatography Mass Spectrometry (LCMS) and tandem MS analyses found the presence of the flavonoid isorhamnetin (3-methylquercetin) in T. biroi honey extract, which was demonstrated as one of the compounds with inhibitory activity against multidrug-resistant Staphylococcus aureus ATCC BAA-44. Our findings suggest that Philippine honey produced by T. biroi is a potential nutraceutical that possesses antibiotic and antioxidant activities.</jats:p
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