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Analysis of gas chromatography/mass spectrometry data for catalytic lignin depolymerization using positive matrix factorization
Various catalytic technologies are being developed to efficiently convert lignin into renewable chemicals. However, due to its complexity, catalytic lignin depolymerization often generates a wide and complex distribution of product compounds. Gas chromatography/mass spectrometry (GC-MS) is a common analytical technique to profile the compounds that comprise lignin depolymerization products. GC-MS is applied not only to determine the product composition, but also to develop an understanding of the catalytic reaction pathways and of the relationships among catalyst structure, reaction conditions, and the resulting compounds generated. Although a very useful tool, the analysis of lignin depolymerization products with GC-MS is limited by the quality and scope of the available mass spectral libraries and the ability to correlate changes in GC-MS chromatograms to changes in lignin structure, catalyst structure, and other reaction conditions. In this study, the GC-MS data of the depolymerization products generated from organosolv hybrid poplar lignin using a copper-doped porous metal oxide catalyst and a methanol/dimethyl carbonate co-solvent was analyzed by applying a factor analysis technique, positive matrix factorization (PMF). Several different solutions for the PMF model were explored. A 13-factor solution sufficiently explains the chemical changes occurring to lignin depolymerization products as a function of lignin, reaction time, catalyst, and solvent. Overall, seven factors were found to represent aromatic compounds, while one factor was defined by aliphatic compounds
Zoom-in-Net: Deep Mining Lesions for Diabetic Retinopathy Detection
We propose a convolution neural network based algorithm for simultaneously
diagnosing diabetic retinopathy and highlighting suspicious regions. Our
contributions are two folds: 1) a network termed Zoom-in-Net which mimics the
zoom-in process of a clinician to examine the retinal images. Trained with only
image-level supervisions, Zoomin-Net can generate attention maps which
highlight suspicious regions, and predicts the disease level accurately based
on both the whole image and its high resolution suspicious patches. 2) Only
four bounding boxes generated from the automatically learned attention maps are
enough to cover 80% of the lesions labeled by an experienced ophthalmologist,
which shows good localization ability of the attention maps. By clustering
features at high response locations on the attention maps, we discover
meaningful clusters which contain potential lesions in diabetic retinopathy.
Experiments show that our algorithm outperform the state-of-the-art methods on
two datasets, EyePACS and Messidor.Comment: accepted by MICCAI 201
Protective Effect of Time Spent Walking on Risk of Stroke in Older Men
BACKGROUND AND PURPOSE: Older adults have the highest risks of stroke and the lowest physical activity levels. It is important to quantify how walking (the predominant form of physical activity in older age) is associated with stroke.
METHODS: A total of 4252 men from a UK population-based cohort reported usual physical activity (regular walking, cycling, recreational activity, and sport) in 1998 to 2000. Nurses took fasting blood samples and made anthropometric measurements.
RESULTS: Among 3435 ambulatory men free from cardiovascular disease and heart failure in 1998 to 2000, 195 first strokes occurred during 11-year follow-up. Men walked a median of 7 (interquartile range, 3â12) hours/wk; walking more hours was associated with lower heart rate, D-dimer, and higher forced expiratory volume in 1 second. Compared with men walking 0 to 3 hours/wk, men walking 4 to 7, 8 to 14, 15 to 21, and >22 hours had age- and region-adjusted hazard ratios (95% confidence intervals) for stroke of 0.89 (0.60â1.31), 0.63 (0.40â1.00), 0.68 (0.35â1.32), and 0.36 (0.14â0.91), respectively, P (trend)=0.006. Hazard ratios were somewhat attenuated by adjustment for established and novel risk markers (inflammatory and hemostatic markers and cardiac function [N-terminal pro-brain natriuretic peptide]) and walking pace, but linear trends remained. There was little evidence for a doseâresponse relationship between walking pace and stroke; comparing average pace or faster to a baseline of slow pace, the hazard ratio for stroke was 0.65 (95% confidence interval, 0.44â0.97), which was fully mediated by time spent walking.
CONCLUSIONS: Time spent walking was associated with reduced risk of onset of stroke in doseâresponse fashion, independent of walking pace. Walking could form an important part of stroke-prevention strategies in older people
Malignant Glaucoma: Report of a Presumed Bilateral Spontaneous Case
Background: Malignant glaucoma is an ocular emergency and may lead to blindness if not promptly recognized and treated effectively. It is usually reported after trabeculectomy, and spontaneous or bilateral cases are not common in the literature.Case report: This article reports the case of a Nigerian woman who developed spontaneous bilateral malignant glaucoma with resultant visual impairment. A literature review on the subject is also undertaken. Possible etiology and management challenges of the case are also discussed.Conclusion: This study is aimed at drawing attention to this potentially blinding eye disease, and ultimately improves knowledge on its diagnosis and management, to reduce the visual morbidity.Key words: Malignant glaucoma, closed angle glaucoma, blindness, visual impairment, aqueous misdirection, vitrectom
Overview of the EU FP7-project HISTORIC
HISTORIC aims to develop and test complex photonic integrated circuits containing a relatively large number of digital photonic elements for use in e.g. all-optical packet switching. These photonic digital units are all-optical flip-flops based on ultra compact laser diodes, such as microdisk lasers and photonic crystal lasers. These lasers are fabricated making use of the heterogeneous integration of InP membranes on top of silicon on insulator (SOI) passive optical circuits. The very small dimensions of the lasers are, at least for some approaches, possible because of the high index contrast of the InP membranes and by making use of the extreme accuracy of CMOS processing.
All-optical flip-flops based on heterogeneously integrated microdisk lasers with diameter of 7.5 mu m have already been demonstrated. They operate with a CW power consumption of a few mW and can switch in 60ps with switching energies as low as 1.8 fJ. Their operation as all-optical gate has also been demonstrated. Work is also on-going to fabricate heterogeneously integrated photonic crystal lasers and all-optical flip-flops based on such lasers. A lot of attention is given to the electrical pumping of the membrane InP-based photonic crystal lasers and to the coupling to SOI wire waveguides. Optically pumped photonic crystal lasers coupled to SOI wires have been demonstrated already.
The all-optical flip-flops and gates will be combined into more complex photonic integrated circuits, implementing all-optical shift registers, D flip-flops, and other all-optical switching building blocks. The possibility to integrate a large number of photonic digital units together, but also to integrate them with compact passive optical routers such as AWGs, opens new perspectives for the design of integrated optical processors or optical buffers. The project therefore also focuses on designing new architectures for such optical processing or buffer chips
The Evolution of Economic Governance in EMU
This paper examines the benefits of co-ordination in EMU in a stylised manner and how these benefits have shaped the co-ordination framework in EMU. It then discusses in detail the co-ordination experience in four areas that are particularly important for the functioning of EMU: (i) fiscal policy co-ordination under the Stability and Growth Pact (SGP); (ii) the co-ordination of structural policies under the Lisbon Strategy for Growth and Jobs; (iii) the representation and co-ordination of euro-area positions in international financial fora; and (iv) the co-ordination of macroeconomic statistics. The thrust of the findings is that EMU's system of economic governance has, overall, proven fit for purpose. The current policy assignment to the institutions and instruments that govern the conduct of economic policy in EMU is sound, even though further progress is necessary in several areas, particularly as regards external representation.Governance, EMU, euro area, co-ordination, van den Noord, Dïżœhring, Langedijk, Nogueira-Martins,Pench, Temprano-Arroyo, Thiel
CURRENT STATUS AND OUTLOOK OF RENEWABLE ENERGY DEVELOPMENT IN NIGERIA
Over 80% of the current Nigerian primary energy consumption is met by petroleum. This overdependence on fossil fuels derived from petroleum for local consumption requirements should be a serious source of concern for the country in two ways â depletion of the resources and negative impact on the environment. This paper presents a critical review of the available renewable energy resources in Nigeria, namely; biomass, hydropower, solar and wind energy. It examines the current energy situation in the country and equally discusses the various energy policy documents developed by the government. Using the scenario-based International Atomic Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this study shows that Nigeria will overcome her present energy crisis if she explores the abundant renewable energy resources in the country. The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria.  http://dx.doi.org/10.4314/njt.v36i1.2
The Delphi and GRADE methodology used in the PSOGI 2018 consensus statement on Pseudomyxoma Peritonei and Peritoneal Mesothelioma
Pseudomyxoma Peritonei (PMP) and Peritoneal Mesothelioma (PM) are both rare peritoneal malignancies. Currently, affected patients may be treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy offering long-term survival or even cure in selected patients. However, many issues regarding the optimal treatment strategy are currently under debate. To aid physicians involved in the treatment of these patients in clinical decision making, the PSOGI executive committee proposed to create a consensus statement on PMP and PM. This manuscript describes the methodology of the consensus process. The Delphi technique is a reliable method for attaining consensus on a topic that lacks scientific evidence through multiple voting rounds which feeds back responses to the participants in between rounds. The GRADE system provides a structured framework for presenting and grading the available evidence. Separate questionnaires were created for PMP and PM and sent during two voting rounds to 80 and 38 experts, respectively. A consensus threshold of 51.0% was chosen. After the second round, consensus was reached on 92.9%â100.0% of the questions. The results were presented and discussed in the plenary session at the PSOGI 2018 international meeting in Paris. A third round for the remaining issues is currently in progress. In conclusion, using the Delphi technique and GRADE methodology, consensus was reached in many issues regarding the treatment of PM and PMP amongst an international panel of experts. The main results will be published in the near future
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