Analysis of Devices for Thermal Energy Consumption Monitoring and Design of A Bench Test for their Characterization

Abstract The mandatory introduction in Italy of the accounting of consumption for heating and domestic hot water in centralized heating systems has determined the introduction on the market of many commercial solutions based on different measuring principles. In order to find a proper method for testing the solutions proposed by the vendors, in the present work the uncertainty of the results reachable with the different types of measuring devices has been evaluated. Based on the best theoretical results achievable with the different types of devices the scheme of a test bed for the characterization of commercial systems is proposed

Statins, fibrates, and venous thromboembolism: a meta-analysis.

Aims The aim is to make a systematic review of the literature to assess the effect of lipid-lowering drugs on venous thromboembolism (VTE) occurrence. Methods and results MEDLINE and EMBASE databases were searched to identify studies that evaluated the effect of lipid-lowering drugs, in particular statins and fibrates, on VTE risk until April 2009. A scoring system was used to divide studies into two quality categories. Odds ratios (ORs) and 95% confidence intervals (CIs) were then calculated and pooled using a fixed and a random-effects model. Statistical heterogeneity was evaluated through the use of I2 statistics. Three randomized controlled trials (RCTs), three cohort, and eight case\u2013control studies were included in our systematic review, for a total of 863 805 patients. Statins use significantly reduced VTE risk [OR, 0.81; 95% CI, 0.66\u20130.99, random-effect model)]. There was a very high heterogeneity among the studies (I2 > 80%). The use of fibrates was associated with a significant increase in the risk of VTE (OR, 1.58; 95% CI, 1.23\u20132.02), without heterogeneity (I2 = 0%). Data on other lipid-lowering drugs were lacking. Conclusion This meta-analysis of available literature suggests that statins may lower the risk of VTE, whereas fibrates may increase this risk. Due to several methodological limitations, this conclusion should be considered with caution, and additional, specifically designed RCTs are warranted

Editor's Choice \u2013 Outcomes of Self Expanding PTFE Covered Stent Versus Bare Metal Stent for Chronic Iliac Artery Occlusion in Matched Cohorts Using Propensity Score Modelling

OBJECTIVES: The aim was to compare outcomes of self expanding PTFE covered stents (CSs) with bare metal stents (BMSs) in the treatment of iliac artery occlusions (IAOs). METHODS: Between January 2009 and December 2015, 128 iliac arteries were stented for IAO. A CS was implanted in 78 iliac arteries (61%) and a BMS in 50 (49%). After propensity score matching, 94 limbs were selected and underwent stenting (47 for each group). Thirty day outcomes and midterm patency were compared; follow-up results were analysed with Kaplan-Meier curves. RESULTS: Overall, iliac lesions were classified by limb as TASC B (19%), C (21%), and D (60%). Technical success was 98%. Comparing CS versus BMS, the early cumulative surgical complication rate (12% vs. 12%, p = 1.0) and 30 day mortality rate (2% vs. 2%, p = 1.0) were equivalent. At 36 months (average 23 \ub1 17), overall primary patency was similar between CS and BMS (87% vs. 66%, p = .06), and this finding was maintained after stratification by TASC B (p = .29) and C (p = .27), but for TASC D, CSs demonstrated a higher patency rate (CS, 88% vs. BMS, 54%; p = .03). In particular, patency was in favour of CSs for IAOs > 3.5 cm in length (p = .04), total lesion length > 6 cm (p = .04), and IAO with calcification > 75% of the arterial wall circumference (p = .01). CONCLUSIONS: Overall, the use of self expanding CS for IAOs has similar early and midterm outcomes compared with BMS. Even if further confirmatory studies are needed, CSs seem to have higher midterm patency rates than BMSs for TASC D lesions, IAOs with a total lesion length > 6 cm, occlusion length > 3.5 cm, and calcification involving > 75% of the arterial wall circumference. These specific anatomical parameters may be useful to the operator when deciding between CS and BMS during endovascular planning

Chemical evolution of primary and formation of secondary biomass burning aerosols during daytime and nighttime

Organic matter (OM) can constitute more than half of fine particulate matter (PM) and affect climate and human health. Natural and man-made biomass burning is an important contributor to primary and secondary OM (POA and SOA) with an increasing trend. Aerosol mass spectrometry (AMS) and Fourier transform infrared spectroscopy (FTIR) are two complementary methods of identifying the complex chemical composition of OM in terms of mass fragments and functional groups, respectively. AMS offers a relatively higher temporal resolution compared to FTIR (performed on PTFE filters). However, the interpretation of AMS mass spectra remains complicated due to the extensive molecular fragmentation. In this study, we used collocated AMS and FTIR measurements to better understand the evolution of biomass burning POA and SOA due to different mechanisms of chemical aging (e.g., homogeneous gasphase oxidation and heterogeneous reactions). Primary emissions from wood and pellet stoves were injected into a 10 m3 environmental chamber located at the Center for Studies of Air Qualities and Climate Change (CSTACC) at ICE-HT/FORTH. Primary emissions were aged using hydroxyl and nitrate radicals with atmospherically relevant exposures. PM1 was analyzed by a highresolution time-of-flight (HR-ToF) and was also collected on PTFE filters over 20-minute periods before and after aging for off-line FTIR analysis. AMS and FTIR measurements agreed well with regards to the concentration of OM and some biomass burning tracers (levoglucosan and lignin; Yazdani A., 2020b) and the OM:OC ratio. Chamber wall loss rates were estimated using AMS OM concentration and were used to split the contribution of POA and SOA. The estimated FTIR and AMS spectra of SOA produced by reactions of biomass burning volatile organic compounds (VOCs) with OH were found to have prominent acid signatures. Organonitrates, on the other hand, appeared to be important for SOA produced by the nitrate radical. We found that with continued aging, SOA evolves and becomes similar to the oxygenated OA (OOA) in the atmosphere. We also found that POA composition also evolves with aging. Our estimates show that up to 10 % of POA mass undergoes aging. Biomass burning tracers such as lignin and levoglucosan in addition to hydrocarbons are among the POA compounds that are lost the most in biomass burning POA (up to 6 times more than OM decrease due to chamber wall losses; Fig. 1). This diminution is observed for both semi-volatile (levoglucosan and hydrocarbons) and non-volatile (lignin) POA species, implying the importance of gasparticle partitioning, heterogeneous reactions, and photolysis for POA evolution in the atmosphere. This result can be important since chemical transport models usually do not consider POA heterogeneous reactions. Figure 1. Trends of individual AMS mass fragments (with contribution to OM> 0.3 %) during aging with UV (starting from time zero). All mass fragments have been normalized by their concentration before the with start of aging and corrected for the chamber wall losses. Important mass fragments are shown in color. This work was supported by the project PyroTRACH (ERC- 2016-COG) funded from H2020-EU.1.1. - Excellent Science - European Research Council (ERC), project ID 726165 and funding from the Swiss National Science Foundation (200021_172923). References Yazdani, A., Dudani, N., Takahama, S., Bertrand, A., Prévôt, A. S. H., El Haddad, I., and Dillner, A. M.: Characterization of Primary and Aged Wood Burning and Coal Combustion Organic Aerosols in Environmental Chamber and Its Implications for Atmospheric Aerosols, Atmospheric Chemistry and Physics Discussions, pp. 1– 32

The oxidizing power of the dark side: Rapid nocturnal aging of biomass burning as an overlooked source of oxidized organic aerosol

Oxidized organic aerosol (OOA) is a major component of ambient particulate matter, substantially affecting both climate and human health. A considerable body of evidence has established that OOA is readily produced in the presence of daylight, thus leading to the association of high concentrations of OOA in the summer or mid-afternoon. However, this current mechanistic understanding fails to explain elevated OOA concentrations during night or wintertime periods of low photochemical activity, thus leading atmospheric models to under predict OOA concentrations by a factor of 3-5. Here we show that fresh emissions from biomass burning rapidly forms OOA in the laboratory over a few hours and without any sunlight. The resulting OOA chemical composition is consistent with the observed OOA in field studies in major urban areas. To estimate the contribution of nocturnally aged OOA in the ambient atmosphere, we incorporate this nighttime-aging mechanism into a chemical-transport model and find that over much of the United States greater than 75% of the OOA formed from fresh biomass burning emissions underwent nighttime aging processes. Thus, the conceptual framework that OOA is predominantly formed in the presence of daylight fails to account for a substantial and rapid oxidation process occurring in the dark

Graves' disease presenting as pseudotumor cerebri: a case report

<p>Abstract</p> <p>Introduction</p> <p>Pseudotumor cerebri is an entity characterized by elevated intracranial pressure with normal cerebrospinal fluid and no structural abnormalities detected on brain MRI scans. Common secondary causes include endocrine pathologies. Hyperthyroidism is very rarely associated and only three case reports have been published so far.</p> <p>Case presentation</p> <p>We report the case of a 31-year-old Luso-African woman with clinical symptoms and laboratory confirmation of Graves' disease that presented as pseudotumor cerebri.</p> <p>Conclusion</p> <p>This is a rare form of presentation of Graves' disease and a rare cause of pseudotumor cerebri. It should be remembered that hyperthyroidism is a potential cause of pseudotumor cerebri.</p

Differentiating between primary and secondary organic aerosols of biomass burning in an environmental chamber with FTIR and AMS

Fine particulate matter (PM) affects visibility, climate and public health. Organic matter (OM), which is hard to characterize due to its complex chemical composition, can constitute more than half of the PM. Biomass burning from residential wood burning, wildfires, and prescribed burning is a major source of OM with an ever-increasing importance. Aerosol mass spectrometry (AMS) and Fourier transform infrared spectroscopy (FTIR) are two complementary methods of identifying the chemical composition of OM. AMS measures the bulk composition of OM with relatively high temporal resolution but provides limited parent compound information. FTIR, carried out on samples collected on Teflon filters, provides detailed functional groupinformation at the expense of relatively low temporal resolution. In this study, we used these two methods to better understand the evolution of biomass burning OM in the atmosphere with aging. For this purpose, primary emissions from wood and pellet stoves were injected into the Center for Studies of Air Qualities and Climate Change (C-STACC) environmental chamber at ICE-HT/FORTH. Primary emissions were aged using hydroxyl and nitrate radicals (with atmospherically relevant exposures) simulating atmospheric day-time and night-time oxidation. A time-of-flight (ToF) AMS reported the composition of non-refractory PM1 every three minutes and PM1 was collected on PTFE filters over 20-minute periods before and after aging for off-line FTIR analysis. We found that AMS and FTIR measurements agreed well in terms of measured OM mass concentration, the OM:OC ratio, and concentration of biomass burning tracers – lignin and levoglucosan. AMS OM concentration was used to estimate chamber wall loss rates which were then used separate the contribution of primary and secondary organic aerosols (POA and SOA) to the aged OM. AMS mass spectra and FTIR spectra of biomass burning SOA and estimates of bulk composition were obtained by this procedure. FTIR and AMS spectra of SOA produced by OH oxidation of biomass burning volatile organic compounds (VOCs) were dominated by acid signatures. Organonitrates, on the other hand, appeared to be important in the SOA aged by the nitrate radical. The spectra from the two instruments also indicated that the signatures of certain compounds such as levoglucosan, lignin and hydrocarbons, which are abundant in biomass burning POA, diminish with aging significantly more than what can be attributed to chamber wall losses. The latter suggests biomass burning POA chemical composition might change noticeably due to heterogeneous reactions or partitioning in the atmosphere. Therefore, the common assumption of stable POA composition is only partially true. In addition, more stable biomass burning tracers should be used to be able to identify highly aged biomass burning aerosols in the atmosphere