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Challenges for the CMS Computing Model in the First Year
CMS is in the process of commissioning a complex detector and a globally distributed computing infrastructure simultaneously. This represents a unique challenge. Even at the beginning there is not sufficient analysis or organized processing resources at CERN alone. In this presentation we discuss the unique computing challenges CMS expects to face during the first year of running and how they influence the baseline computing model decisions. During the early accelerator commissioning periods, CMS will attempt to collect as many events as possible when the beam is on in order to provide adequate early commissioning data. Some of these plans involve overdriving the Tier-0 infrastructure during data collection with recovery when the beam is off. In addition to the larger number of triggered events, there will be pressure in the first year to collect and analyze more complete data formats as the summarized formats mature. The large event formats impact the required storage, bandwidth, and processing capacity across all the computing centers. While the understanding of the detector and the event selections is being improved, there will likely be a larger number of reconstruction passes and skims performed by both central operations and individual users. We discuss how these additional stresses impact the allocation of resources and the changes from the baseline computing model
The first Year of LHC Physics Analysis Using the Grid: Prospects from CMS
The CMS computing model has been distributed since early in the experiment preparation. In order for the experiment to succeed, CMS needs to develop efficient distributed analysis techniques using grid services. CMS has an active program of development and deployment to ensure the experiment can perform analysis using a worldwide infrastructure of computing clusters already at the beginning of LHC operation. In this presentation the status, plans, and prospects for CMS analysis using the grid are outlined
Cognitive enhancers derived from edible crops
The concept of an effective cognitive boosting nootropic supplement is gaining traction with consumers, neuroscientists and regulators alike and it is therefore unsurprising that scientifically validated Nootropics are highly prized. New research demonstrates edible crops could be useful sources to mine for new nootropics; plant extracts enriched with an array of cognitive enhancing metabolites. There is merit in investigating these plant species. Metadata has identifies consuming specific fruit and vegetables positively affects cognitive function; therefore these same edible crop plants present as opportunities for developing nootropic formulations. This hypothesis is supported by positive data obtained through clinical testing [e.g. extracts of tomato (Solanum lycopersicum), herbs from the Genus Salvia, cocoa (Theobroma), tea (Camellia sinensisor) and coffee (Coffea Arabica). This review will discuss clinically tested cognitive enhancers derived from edible crop species and discuss their use alongside other classes of nootropics
Innovative ingredients and emerging technologies for controlling ice recrystallisation, texture and structure stability in frozen dairy desserts: a review
Over the past decade, ice cream manufacturers have developed a strong understanding of the functionality of key ingredients and processing, developing effective explanations for the link between structure forming agents, stability mechanisms and perceived quality. Increasing demand for products perceived as healthier / more natural with minimal processing has identified a number of new tools to improve quality and storage stability of frozen dairy desserts. Ingredients such as dietary fibre, polysaccharides, prebiotics, alternate sweeteners, fat sources rich in unsaturated fatty acids and ice structuring proteins have been successfully applied as cryoprotective, texturizing and structuring agents. Emerging minimal processing technologies including hydrostatic pressure processing, ultrasonic or high pressure assisted freezing, low temperature extrusion and enzymatically induced biopolymers crosslinking have been evaluated for their ability to improve colloidal stability, texture and sensory quality. It is therefore timely for a comprehensive review
Soybean (Glycine max) oil bodies and their associated phytochemicals
Abstract: Soybean oil bodies were isolated from 3 cultivars (Ustie, K98, and Elena) and the occurrence of 2 classes of phytochemicals (tocopherol isoforms and isoflavones) and strength of their association with isolated oil bodies was evaluated. Tocopherol is shown to be closely associated with soybean oil bodies; δ-tocopherol demonstrated a significantly greater association with oil bodies over other tocopherol isoforms. Isoflavones do not show a significant physical association with oil bodies, although there is some indication of a passive association of the more hydrophobic aglycones during oil body isolation.
Practical Application: Oil bodies are small droplets of oil that are stored as energy reserves in the seeds of oil seeds, and have the potential to be used as future food ingredients. If oil body suspensions are commercialized on a large scale, knowledge of the association of phytochemicals with oil bodies will be valuable in deciding species of preference and predicting shelf life and nutritional value
Physicochemical characterisation of sunflower seed oil bodies ex-vivo
Oilseeds store energy as triacylglycerides during periods of dormancy in preparation for germination and the early stages of development. The triacylglyceride is stored in discrete organelles termed oil bodies. Oil bodies are formed during the synthesis of neutral lipids within the bilayer of cellular endoplasmic reticulum (ER); as lipid is synthesised it forms droplets of oil that swell distending the ER membrane and at a critical diameter separate from the ER by vesiculation forming independent organelles. These organelles are structurally stabilised by a phospholipid monolayer originating from the ER and the addition of highly amphiphilic oleosin proteins.
Oil bodies have been shown previously to be extremely stable organelles that can be easily extracted and purified from oilseeds; our aim was to develop an understanding of the physical and chemical properties of sunflower oil bodies ex-vivo prior to their subsequent use in commercial products. Several novel findings were elucidated through this work: oil body phytochemical composition, their physical and oxidative stability and their ability to store and deliver flavour compounds.
It was hypothesised that tocopherol is tightly associated with sunflower oil bodies. This was tested by recovering oil bodies from sunflower seed and washing them to remove extraneous proteins and associated phenolic compounds. Tocopherol remained with washed oil bodies (392 mg tocopherol.kg-1 oil body oil) and this population of tocopherol represented 38% of the total seed tocopherol. It was hypothesised that this high tocopherol concentration and its intrinsic association to oil body structures would contribute to an increased level of oxidative stability.
Sunflower seed lipids were significantly more resistant to thermally induced oxidation when stabilised in oil body suspensions compared to sunflower oil emulsions stabilised by a range of commercial emulsifiers (sodium dodecyl sulfate, polyoxyethylenesorbitan monolaurate (tween 20) and dodecyltrimethylammonium bromide). Oxidative stability was assessed through lipid hydroperoxide concentration and the concentration of headspace hexanal. Maximum lipid hydroperoxide concentration in surfactant stabilised emulsions after 8 days at 45oC ranged between 26 and 333 mmol lipid hydroperoxide.kg-1 oil whereas lipid hydroperoxide concentrations in oil body suspensions did not exceed 12 mmol lipid hydroperoxide.kg-1 oil. In addition there was no development in oxidative rancidity over the 8 day storage trial of oil bodies stored at 5oC.
The composition of phospholipids in a range of oil body preparations was assessed; purified oil bodies contained principally phosphatidylcholine (91%) and a smaller fraction of phosphatidylethanolamine (9%). Less purified preparations contained other phospholipid species; the presence of which was explained by contamination with either non-intrinsic cellular phospholipids or phospholipase D that catalysed the breakdown of phospholipids to phosphatidic acid.
Mechanisms and the extent of oil body physical stability were assessed using charge analysis and resistance of oil body preparations to changes in temperature and pH. Oil bodies are stabilised by a combination of steric hindrance and electrostatic repulsion provided by the surface proteins and phospholipids. Oil bodies had a zeta potential of -30mV at neutral pH and the surface charge was pH dependant with an apparent isoelectric point of between pH3 and pH6 was calculated from electrophoretic mobility, streaming potential and creaming stability measurements. Purified oil bodies were physically stable to thermal stresses up to 45oC for 2 days, although less purified preparations lost structural integrity at temperatures above 25oC. When assessed for their ability to delivery flavour molecules, oil bodies had comparable bulk phase properties to artificial emulsions stabilised by tween 20. Oil bodies did show a greater rate of flavour delivery during headspace dilution, when compared with the model artificial emulsions, suggesting commercial benefits may be gained through the incorporation of oil bodies into commercial emulsions.
The key findings of this work are that oil bodies are extremely stable organelles that are resistant to thermal stress and physical processing. When lipid is stored within oil bodies it has greater resistance to the onset of lipid oxidation which may be explained by the intrinsic association of phospholipids, proteins and phytochemicals (vitamin E)
Application of calibrations to hyperspectral images of food grains: example for wheat falling number
The presence of a few kernels with sprouting problems in a batch of wheat can result in enzymatic activity sufficient to compromise flour functionality and bread quality. This is commonly assessed using the Hagberg Falling Number (HFN) method, which is a batch analysis. Hyperspectral imaging (HSI) can provide analysis at the single grain level with potential for improved performance. The present paper deals with the development and application of calibrations obtained using an HSI system working in the near infrared (NIR) region (~900–2500 nm) and reference measurements of HFN. A partial least squares regression calibration has been built using 425 wheat samples with a HFN range of 62–318 s, including field and laboratory pre-germinated samples placed under wet conditions. Two different approaches were tested to apply calibrations: i) application of the calibration to each pixel, followed by calculation of the average of the resulting values for each object (kernel); ii) calculation of the average spectrum for each object, followed by application of the calibration to the mean spectrum. The calibration performance achieved for HFN (R2 = 0.6; RMSEC ~ 50 s; RMSEP ~ 63 s) compares favourably with other studies using NIR spectroscopy. Linear spectral pre-treatments lead to similar results when applying the two methods, while non-linear treatments such as standard normal variant showed obvious differences between these approaches. A classification model based on linear discriminant analysis (LDA) was also applied to segregate wheat kernels into low (250 s) HFN groups. LDA correctly classified 86.4% of the samples, with a classification accuracy of 97.9% when using HFN threshold of 150 s. These results are promising in terms of wheat quality assessment using a rapid and non-destructive technique which is able to analyse wheat properties on a single-kernel basis, and to classify samples as acceptable or unacceptable for flour production
Atmospheric pressure chemical ionisation mass spectrometry analysis linked with chemometrics for food classification – a case study: geographical provenance and cultivar classification of monovarietal clarified apple juices
In the present work, we have evaluated for first time the feasibility of APCI-MS volatile compound fingerprinting in conjunction with chemometrics (PLS-DA) as a new strategy for rapid and non-destructive food classification. For this purpose 202 clarified monovarietal juices extracted from apples differing in their botanical and geographical origin were used for evaluation of the performance of APCI-MS as a classification tool. For an independent test set PLS-DA analyses of pre-treated spectral data gave 100% and 94.2% correct classification rate for the classification by cultivar and geographical origin, respectively. Moreover, PLS-DA analysis of APCI-MS in conjunction with GC-MS data revealed that masses within the spectral ACPI-MS data set were related with parent ions or fragments of alkyesters, carbonyl compounds (hexanal, trans-2-hexenal) and alcohols (1-hexanol, 1-butanol, cis-3-hexenol) and had significant discriminating power both in terms of cultivar and geographical origin
Role of the IL-33/ST2 axis in cardiovascular disease: A systematic review and meta-analysis.
Funder: National Institute of Health Research Cambridge Biomedical Research CentreFunder: AstraZenecaFunder: Cambridge University Hospitals NHS Foundation TrustFunder: British Heart FoundationFunder: National Institute for Health Research (NIHR)UNLABELLED: Interleukin (IL)-33 and its unique receptor, ST2, play a pivotal role in the immune response to infection and stress. However, there have been conflicting reports of the role of IL-33 in cardiovascular disease (CVD) and the potential of this axis in differentiating CVD patients and controls and with CVD disease severity, remains unclear. AIMS: 1) To quantify differences in circulating IL-33 and/or sST2 levels between CVD patients versus controls. 2) Determine association of these biomarkers with mortality in CVD and community cohorts. METHODS AND RESULTS: Using Pubmed/MEDLINE, Web of Science, Prospero and Cochrane databases, systematic review of studies published on IL-33 and/or sST2 levels in patients with CVD (heart failure, acute coronary syndrome, atrial fibrillation, stroke, coronary artery disease and hypertension) vs controls, and in cohorts of each CVD subtype was performed. Pooled standardised mean difference (SMD) of biomarker levels between CVD-cases versus controls and hazard ratios (HRs) for risk of mortality during follow-up in CVD patients, were assessed by random effects meta-analyses. Heterogeneity was evaluated with random-effects meta-regressions. From 1071 studies screened, 77 were meta-analysed. IL-33 levels were lower in HF and CAD patients vs controls, however levels were higher in stroke patients compared controls [Meta-SMD 1.455, 95% CI 0.372-2.537; p = 0.008, I2 = 97.645]. Soluble ST2 had a stronger association with risk of all-cause mortality in ACS (Meta-multivariate HR 2.207, 95% CI 1.160-4.198; p = 0.016, I2 = 95.661) than risk of all-cause mortality in HF (Meta-multivariate HR 1.425, 95% CI 1.268-1.601; p<0.0001, I2 = 92.276). There were insufficient data to examine the association of IL-33 with clinical outcomes in CVD. CONCLUSIONS: IL-33 and sST2 levels differ between CVD patients and controls. Higher levels of sST2 are associated with increased mortality in individuals with CVD. Further study of IL-33/ST2 in cardiovascular studies is essential to progress diagnostic and therapeutic advances related to IL-33/ST2 signalling
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