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Carbon dioxide (CO2) conversion processes can be a promising alternative to replace conventional processes toward a more sustainable industry. The addition of ionic liquids (IL) was reported to increase the performance of related reactions; however, their thermodynamic influence in the reactive chemical equilibrium has been poorly investigated. This study evaluated the effect of the ionic liquids (ILs) [BMIm]BF4], [BMIm][PF6], or [BMIm][NTf2] on the CO2 hydrogenation to carbon monoxide (CO) chemical equilibrium. Predictive and nonpredictive approaches based on the Predictive Soave-Redlich-Kwong equation of state were applied to represent pure ILs densities and vapor pressure. The nonpredictive approach presented the most suitable representation and was applied to represent binary vapor-liquid and liquid-liquid phase equilibria of ILs + CO2, hydrogen (H2), CO, or water (H2O). The influence of temperature pressure, and IL content on CO2 hydrogenation to CO reaction were evaluated. Higher ILs’ molar ratio increased the equilibrium conversion. IL-containing systems are significantly influenced by pressure, and high pressures enhance CO2 conversion. High temperatures increased the reaction’s conversion of systems containing the hydrophobic ILs [BMIm][PF6] or [BMIm][NTf2], while low temperatures increased the CO production of systems containing the hydrophilic IL [BMIm][BF4]. This effect was attributed to the high influence of temperature on the water sorption in the IL. The hydrophilic IL, [BMIm][BF4], promoted the highest increase in CO2 conversion. At 348 K and 2.0 MPa, the CO2 conversion was increased from 1.1–54.1%; roughly an increase of ~ 50 times the original conversion without IL addition.

SUMMARY The aim of this clinical report is to present a possible alternative treatment, with 24-month follow-up, for restoring tooth loss due to extensive erosive tooth wear. A 21-year-old male patient, complaining of intense sensitivity in the maxillary posterior teeth, and presenting severe wear on maxillary premolar and molar teeth due to gastroesophageal reflux, sought care in the university clinics. The planned treatment was to refer for medical treatment and perform restorations with the high-viscosity glass ionomer cement Equia Forte (GC Corporation, Tokyo, Japan), aiming to restore the dental anatomy and to consequently decrease the pain symptomatology. A silicone guide, obtained from a diagnostic waxing, was used during the restorative approach considering the patient’s occlusion. After all the clinical steps of the restorative technique, an occlusal adjustment of restorations was performed. During monthly recalls up to 24 months, the treatment was stable and in service. In addition, the patient reported no pain and improved chewing, leading to a better quality of life.

The use of fossil resources has lead to great increase in concentration of carbon dioxide (CO2) in the atmosphere beyond sustainable limits, which causes environmental issues such as greenhouse gas effect, climate change and extreme weather events and threats the human life. Thus, several researches have been focused on mitigate this problem. Possible strategies involve implementing technologies of carbon capture storage and utilization. Among them, integrated processes for carbon dioxide capture and its conversion into value-added products have gained attention. Carbon dioxide hydrogenation is among the most developed technologies for its conversion, but requires an external hydrogen (H2) source. Since the conversion of carbon dioxide is highly energy-demanding, assessing its overall process sustainability requires a comprehensive study on the whole system, including its raw material sources (carbon dioxide and hydrogen). Thus, this work proposes a multi-criteria framework to select suitable sources of carbon dioxide and hydrogen to be used in the conversion of carbon dioxide. Potential sources of carbon dioxide (from power plants to ethanol fermentation) and hydrogen (from dedicated production to by-product hydrogen) were evaluated considering environmental, economic, and technical aspects associated with the usage of each source. The Technique of Order Preference Similarity to the Ideal Solution (TOPSIS) is the multi-criteria decision analysis method used to aggregate the criteria and to rank each source individually and further in a pair-wise assessment to identify potential synergic combinations between carbon dioxide and hydrogen sources. Results suggested that using carbon dioxide from natural gas steam reforming, iron and steel industries, ethylene oxide and other high concentration point sources may be the ideal choice for sustainability. The analysis also indicated that hydrogen may be more sustainable if it is a process by-product or is produced by low-cost wind-powered electrolysis. It is important to consider that the analysis is based on several specific data inputs and assumptions, and that a lower score does not mean that the source is not worth investing in.

Direct hydrogenation of carbon dioxide (CO2) to formic acid is unfavorable thermodynamically, which makes its production limited. In this study, a thermodynamic analysis of CO2 hydrogenation to binary product systems of methanol and formic acid promoted by ionic liquid (IL) (1-ethyl-2,3-dimethylimidazolium nitrite, ([Edmim][NO2]) is presented. The analysis is conducted in Aspen Plus using the Gibbs energy minimization approach combined with a vapor–liquid equilibrium (VLE) for the solvation of CO2 in IL. It is demonstrated that solvating CO2 in ILs is an attractive alternative to overcome the thermodynamic difficulty associated with the product yield, especially formic acid. The [Edmim][NO2] promoted system is very effective for the simultaneous production of formic acid and methanol at 25 °C and 17 bar with a yield of 35% formic acid and 30% methanol at a CO2/H2/IL ratio of 1/2/2. The results show a marked improvement in the yield of formic acid to other previously conducted studies on formic acid production.

Summary Drought periods are common events in the semi-arid zone of Chile and their length and frequency has increased with climate change. Within periods of water resource stresses, subsurface water exploitation increases with the use of deeper wells for irrigation and drinking water supplies. Moreover, in case of severe droughts, aquifers could contain a reserve to mitigate the drought. Within this study, we aim to test the feasibility of electromagnetic geophysical methods to map groundwater reserve in a mountainous watershed of the semi-arid Andes, characterized by narrow valleys alluvial fillings within plutonic and volcanic sequences. The area of study is part of the Limari catchment, in the Coquimbo Region, where information about the amount of underground water available and its depth is scarce. Here we present the first results, interpretation and limitations of the application of transient electromagnetic (TEM) and magnetic resonance soundings (MRS) for the characterization of the Limari catchment alluvial aquifers.

Glycerol from biodiesel is a potential raw material for synthesis of several products with high added value. The world demand and the market value of these products are important information for defining the best investment for the implantation of a biorefinery. The information is available on websites of social associations, production companies and market consulting companies and can be mined, free of charge. The International Trade Center (ITC), with information on world trade and websites linked to the foreign trade agencies of every country, such as Comex Stat, in Brazil, are relevant search sources. In this context, this work presents procedures and search techniques for prospecting such information. Such a procedure is illustrated through a case study for which a search of market parameters for glycerol and its derivatives was carried out for use in the process design and economic evaluation of an industrial plant. It was found that crude glycerol had a market price close to US$ 170/ton, in 2019. Among its derivatives, acrylic acid, acrylonitrile and 1,3-propanediol have great potential for the development of new processes, within the scope of a biorefinery. Industrially, acrylic acid (US$ 1100/ton) and acrylonitrile (US$ 1500/ton) are produced from propene (US$ 880/ ton) and 1,3-propanediol (US $ 2000/ton) comes from glucose (US$ 460/t) or ethylene oxide (US$ 1200/t), which encourages the development of new sustainable processes.

New synthetic routes to acetic acid production using CO2 have been studied, such as methanol hydrocarboxylation, reaction of methane with CO2, lignin with CO2 and CO2 hydrogenation. They represent a significant progress in synthetic chemistry, with the novel approach to acetic acid production and CO2 transformation. These innovative routes can replace fossil raw materials by CO2, additionally promote CO2.abatement. This study presents an assessment of acetic acid production from CO2 and identification of the most promising route by a multicriteria decision analysis, including process demand and characteristics, and a shortcut exergy criterion. Methanol hydrocarboxylation has demonstrated to be the best one. The process was designed based on hierarchical approach process synthesis in Aspen Plus simulator to verify its technical feasibility. An exergetic analysis was carried out in the proposed process design to evaluate thermodynamic inefficiencies. The gas recompression and the gas separation system presented the highest exergy destruction, in which possible process intensification or enhancements potentially improve the process.

Carbon dioxide can be used as feedstock to produce chemicals. It represents a stimulating defiance to manufacture novel cost competitive materials with less environmental impact, besides to investigate new opportunities for catalysts and industrial chemistry. The contribution of carbon dioxide conversion goes beyond lowering global warming, by reducing fossil resource depletion or even yielding more benign production pathways. Albeit promising, the literature data regarding the quantity of energy needed to convert carbon dioxide into chemicals is limited and narrowed to the most studied processes and products. In order to understand and model the formation of species using carbon dioxide as raw material, some basic thermodynamic data are needed. The development of detailed reaction schemes in the field is also scarce. To enhance and further complete the database of the products obtained from carbon dioxide, this study investigates different procedures to estimate the basic thermodynamic properties of the reactants and products of these reactions. To date various methods have been developed and introduced to determine the gas-phase standard enthalpies of formation and Gibbs energy. Among them, group additivity and semi-empirical methods are widely employed due to their accuracy and effort time for implementation compared to more rigorous methods. Semi empirical quantum-chemistry methods were compared with group additivity methods. Available literature data were used to select the best method for property estimation of the whole set of species, whereby produced from carbon dioxide. The products from carbon dioxide were categorized in sixteen chemical classes, the reaction enthalpy for the direct route to manufacture the products were assessed and indicate a large difference among the classes. The results of this investigation show that semi empirical quantum-chemistry methods revealed to be more accurate for the studied species; additionally, the method demonstrates robustness in estimating the properties. Together, these results provide important insights into the thermodynamics of carbon dioxide related products.

This paper explores the production of two intermediate chemicals with wide uses in industrial scale. The CO2 hydrogenation using ammonia as an alkyl base produces ammonium formate and carbamate suitable for formic acid and urea synthesis. For this, an investigative simulation study was carried out to explore the possible operating conditions for each product. The given results pointed out that 50 °C and 1 bar favour the production of carbamate, obtaining 99% of yield and decrease formate one to less than 1%. However, low temperature (10 °C) and high pressure (50 bar) promote the formate yield to 81% and smaller quantities of carbamate, around 8%. CO2 conversion is around 99% at 50 °C and 1 bar, when H2O/NH3 ratio is 2.

Several international agreements, focused on regulating greenhouse gases emissions in the atmosphere, were created due to the growing concern about the climate change due to human action. The carbon dioxide (CO2) emissions account for more than 70% of the total greenhouse gases emissions; among the CO2 emitting sectors, electricity generation accounts for 25% of the global emissions. CO2 emissions from Brazilian power plants motivated their mapping, a method was proposed to performance a local market analysis for potential products from CO2 chemical conversion. The forecast behavior of this market for 2030 was also calculated. Among the studied products, methanol, polycarbonates, formic acid and acetaldehyde are the most promising for local manufacture. The States of Sao Paulo, Parana, Amazonas, Bahia, Rio Grande do Sul and Santa Catarina are the most promising regions in terms of potential of CO2 utilization.

Background:Wireless vital parameter continuous monitoring (WVPCM) is compared to regular nurse monitoring in order to provide data on the clinical and economic impact of critically ill patients (CIPs) in Internal Medicine Units (IMU). Study Design:Pilot prospective randomized controlled open-label multi-center study with WIN@Hospital wearable wireless system creating alerts on portable devices (ipad). Experimental Arm:CIPs with MEWS (Modified Early Warning Score) ≥ 3 and/or NEWS (National Early Warning Score) ≥ 5 at admission underwent WCPCM over the first 72 h. Active Comparator:CIPs with MEWS ≥ 3 and/or NEWS ≥ 5 at admission undergoing regular nurse monitoring. Primary outcomes:Reduction of major complications (MC) from 15% to 5%. Secondary outcomes:One day reduction in length of stay (LOS); reduced nurse monitoring time; accurate patient stratification and definition of end stage disease. Statistical methods:According to the preliminary study (Manerbio, 2016), 27% of hospitalized patients, of which 15% have MC, are critical (MEWS ≥3), and require monitoring. Clinical significance is set at 5% relative reduction in MCs in the experimental arm. 148 patients shall be recruited per arm (total 296; calculated by setting the alpha error at 5%, beta error at 20%, 80% test power, 5% loss). Preliminary results:Enrolled 95 and evaluable 89 patients (35 M/54 F), mean age 80.5 years, Comorbidity: Cumulative Illness Rating Scale CIRS-CI: 4, CIRS SI: 1.8. About 38% scored a BRASS (Blaylock Risk Assessment Screening Score) ≥20 indicating need for discharge planning requiring step-down care. More than 50% of patients present IIA index >3 indicating high dependency from nursing assistance. Nurses saved a minimum of 49,6 minutes to a maximum of 58,1 minutes on time spent monitoring each patient per day. Conclusions:WVPCM, detecting early deterioration in CIPs, may facilitate timely response in at-risk patients, increasing safety and reducing costs.

The production of chemicals and fuels from carbon dioxide can lead to a sustainable low carbon pathway for the chemical industry. The use of carbon dioxide as feedstock poses a commercially challenge, which is to develop alternative raw materials at lower cost and also to lower manufacturing impacts. Many products can be developed from carbon dioxide as raw material through carboxylation or hydrogenation reactions. In carbon capture and utilization (CCU), a particular carbon dioxide utilization technology shows specific aspects for emission reduction potential, intrinsic thermodynamic restrictions and commercial maturity level. Each product brings some advantages and penalties, making it therefore important to define some criteria to evaluate and to choose the most attractive products. This study proposes an exploratory screening procedure to identify promising chemical targets to be produced from carbon dioxide conversion among a large number of candidates. In the methodological framework, a systematic literature search is conducted to point out important criteria to take into account, followed by the selection of a multicriteria decision analysis tool that best fits to the data under study. The final step applies a three-level screening, in which important factors, such as thermodynamic data, market size and growth, price of product and carbon dioxide utilization ratio are considered. The results of the evaluation demonstrate that dimethyl carbonate, acetic acid and dimethyl ether are promising products for further study. Such a procedure would accelerate the development into the chemical design process of novel CCU technologies.

A study on process alternatives for reducing steam consumption was carried out in a multistage evaporation system of a chlorine–alkali industrial complex. A phenomenological model was developed, based on the mass and energy balances and on gas–liquid equilibrium correlations for the ternary mixture of caustic soda, sodium chloride and water. The design specifications of the plant were adopted as a reference to validate the mathematical model, which comprises 153 nonlinear equations. Different process conditions were simulated by taking into account the most important process variables and their effect on steam consumption. Differently from previously published studies, in which the conservation laws are mainly focused on the heat exchangers and their optimization, the present study considers the whole multistage evaporation unit. The model also enabled to evaluate the effect of changes in the plant configuration, either by considering a side product stream at a specified concentration, designated to another production unit in the industrial complex, or by including mechanical vapor recompression, which has proven to be a better solution to reduce steam consumption from the energy and exergy points of view. Results indicate an expressive decrease in steam consumption to around 1% of the original configuration. Moreover, from the exergy perspective, if the power generation is considered, the MVR is a better choice from the energy and exergy point of view.

In petroleum refineries, water is used in desalting units to remove the salt contained in crude oil. Typically, 7 % of the volume of hot crude oil is water, forming a water-and-oil emulsion. The emulsion flows between two electrodes and is subjected to an electric field. The electrical forces promote the coalescence of small droplets of water dispersed in crude oil, and these form bigger droplets. This paper calculates the forces acting on the droplets, highlighting particularly the mechanisms proposed for droplet―droplet coalescence under the influence of an applied electric field. Moreover, a model is developed in order to calculate the displacement speed of the droplets and the time between droplet collisions. Thus, it is possible to simulate and optimize the process by changing the operational variables (temperature, electrical field, and water quantity). The main advantage of this study is to show that it is feasible to increase the volume of water recycled in desalting processes, thus reducing the use of freshwater and the generation of liquid effluents in refineries.

Chronic obstructive pulmonary disease (COPD) is the fourth cause of dead in the world. Because of high incidence of comorbidities in COPD patients, it has been proposed a new hypothesis that inscribe this disease in a complex contest named chronic systemic inflammatory syndrome (CSIS). Either COPD and the most common comorbidities responsible for its clinical and natural history, like hypertension, diabetes, coronary artery disease, heart failure, recognize a pro-inflammatory state, marked, for example, by elevated C reactive protein (CRP).113 consecutive patients presenting to emergency department (ED) with acute exacerbated COPD were enrolled. They underwent to full medical history and physical examination. CRP was measured at ED arrival, discharge and at 1-6-12 month follow up. CSIS was diagnosed according to specified criteria.CSIS was diagnosed in 84% patients. CRP was maximally increased at admission during the exacerbation, but didn't correlate with the severity of it. At discharge, CRP values were lowest; during follow up, CRP demonstrated a chaotic behavior growing up till 6 month without any correlation with new exacerbation events. At 1 year it decreased, never reaching normal values in the majority of our patients thus confirming the presence of a persistent inflammation in COPD.CSIS was diagnosed in 84% of our population demonstrating that COPD patients need to be approached in a multidisciplinary way.

Water is used in petroleum desalting units to dilute and remove the salted water droplets that the crude oil contains. The basic processes promote the coalescence of small droplets of conducting water dispersed in a crude oil emulsion. In order to make separation easier, the emulsion is distributed horizontally between two electrodes and subjected to an electrical field, which generates an attractive force among the droplets, promoting coalescence phenomena and further sedimentation. The main purpose of this study is to reduce the demand of fresh water and the liquid effluent generation in refineries. This paper presents a new model developed in order to calculate the droplets velocity by using the balance of the acting forces. The model is able to determine the droplets trajectory in order to define if they can be separated from the continuous phase. Besides the deterministic approaches based on traditional equations, the model uses also the concept of cellular automata. Thus it is possible to solve the problem in a stochastic way and to show visually the sequence of droplets collisions and coalescence phenomena. This methodology enables to calculate the amount of water that can be separated of the emulsion for a number of different operating conditions and then to optimize the process. Comparisons between the obtained results by the developed model and the operational performance of a real desalting unit are carried out. A good accuracy is observed, which shows that the real process is very well represented by the developed model.

The aim of this work is to present a mathematical model developed in order to simulate several operating scenarios involving water supply to a vapor generation unit in a petrochemical plant. The operational strategy suggested involves steady state and dynamic considerations. The case study is a petrochemical plant that uses water from two distinct sources with different qualities and prices. Thus, two case studies were carried out: 1. definition of the optimal proportion between both sources of water in case of supply stability: a model based on the minimum total cost per cubic meter of useful water was developed; 2. definition of the best operational strategy in case of failure in the main water source: a dynamic model was developed representing the flow rates as a time-dependent mathematical function in order to evaluate possible disturbances and all the operating conditions of interests, including the risk of total lack of water for vapor generation, which would cause the whole plant to shut down. The results show that it is possible to preserve operational continuity and stability, with lower water consumption and wastewater generation.

This paper presents a procedure to optimize a real problem of freshwater and wastewater reuse allocation. The case study is an industrial polypropylene unit and the solution, achieved is an almost zero discharge case. The problem was decomposed into subsystems according the type of approach used to water minimization: process changes, regeneration reuse and regeneration recycling. For the regeneration approach, an innovative photochemical process capable to remove all the organic compounds contained in the wastewater in order to make it suitable to be reused in the process was used. For process changes approach, since the major water used in factory is for the cooling process system, a hybrid system composed by air cooler and wet cooling tower is been proposed to replace the wet cooling tower. The air cooler system is used first and the final temperature approach is achieved by the wet cooling tower. Thus, the main scope of the present work is to show that is possible to reach the “almost zero discharge” for an industrial case by using innovative wastewater treatment technologies together with optimization of water/air cooling systems. The results obtained prove that the water minimization techniques used can effectively reduce overall fresh water demand and the overall effluent generated, resulting in lower costs of fresh water and effluent treatment costs.

Major questions are whether mothers infected with the Human Immunodeficiency Virus type 1 (HIV-1) transmit the virus through breast milk and the magnitude of the additional transmission risk. The demonstration of a dose-response effect is an epidemiological method to demonstrate causality. Thus, a study was carried out by the Italian Register for HIV Infection in Children on 961 children of known infection status. Duration of breast-feeding was considered as the level of exposure in 168 ever breast-fed children. Results showed that duration of practice significantly increased the risk of transmission. The adjusted infection odds ratio for one day of breast- versus exclusive formula-feeding was 1.19 with narrow confidence limits (1.10-1.28). In a second study by the Register on 556 children of known infection status and derived prospectively, an infection odds ratio of 2.55 (confidence interval: 1.03-6.37) was calculated in breast- versus exclusively formula-fed children. Several lines of evidence, including the above-mentioned data from the Italian Register for HIV Infection in Children, showed a contribution of breast-feeding to mother-to-child HIV-1 transmission. Thus, this practice is now discouraged in HIV-1 infected mothers living in industrialized societies where formula feeding is practical and attainable. Mode of feeding was known in 2183 children enrolled in the Register and born to HIV-1 infected mothers since 1981. It could be observed that feeding habits of at-risk infants changed in Italy in the middle 1980s, when a large majority of subjects was identified at birth.(ABSTRACT TRUNCATED AT 250 WORDS)

A project for a Demotic Inscriptions on Ostraka Database is being carried out in collaboration between ILC/CNR (Pisa), the Dpt. of Electronic Engineering (Calabria University) and the Dpt. of the Ancient World History (Egyptological section, Pisa University). The aim of the project is to analyse the digital colour images of demotic texts on Ostraka (Medinat Madi, in Fayyum region) with the aid of compiutational tools. The module descrobed in the paper is a neural component able to learn the graphical features of each demotic symbol, which has been previously segmented in the images thanks to a semiautomatic procedure. A specific neural network tries to recognise the text written in the images linking the symbols segmented within the ostraka images database to the correspondent symbols available on a virtual keyboard. The graphical interface is particularly useful for teaching and research activities on this type of archaeological documentation.

Ghrelin is an acylated peptide recently isolated from rat and human stomach that potently stimulates GH release in vivo and in vitro in rats and humans. Ghrelin specifically activates the receptor for the growth hormone secretagogues (GHS) and it has been proposed that it may be the endogenous ligand mimicked by these synthetic compounds. Ghrelin is primarily produced in endocrine cells of the stomach, and to a lesser extent, in other peripheral tissues, including the pituitary. Although ghrelin is the most potent GH-secretagogue so far identified, its circulating levels do not correlate with those of GH either in physiological and pathological conditions. Because of these and many other observations, it may be postulated that ghrelin is not physiologically involved in the regulation of growth hormone secretion. Nonetheless, ghrelin may serve as a very useful model for the development of more potent synthetic GHS, which may be therapeutically useful for the treatment of human GH deficiency.

The signs that may arise after perinatal infection with human immunodeficiency virus type 1 (HIV-1) have been classified by the Centers for Disease Control, but the clinical usefulness of the classification system and the prognostic importance of each disease pattern have not been established. We sought to address these issues by analysing data from the Italian Register for HIV infection in children. We studied 1887 children born to HIV-1-seropositive mothers. 1045 were identified at birth and the others were registered later (median age 4.8 [range 0.4-72] months). HIV-1-associated signs developed in 433 (81.8%) of 529 seropositive infected children at a median age of 5 (0.03-84) months. These signs appeared significantly earlier in the 102 children who died of HIV-1-related illness than in those who are still alive (median 3 [0.03-55] vs 6 [0.03-84] months; p less than 0.001). The cumulative proportion surviving at age 9 years was 49.5% (95% confidence interval 27-65%) and the median survival time was 96.2 months. Separate analysis of the 112 seropositive infected children followed from birth and older than 15 months gave similar results. Hepatomegaly, splenomegaly, lymphadenopathy, parotitis, skin diseases, and recurrent respiratory tract infections formed the mildest disease pattern. Lymphoid interstitial pneumonitis and thrombocytopenia were signs of intermediate disease. By contrast, in multivariate analysis specific secondary infectious diseases, severe bacterial infections, progressive neurological disease, anaemia, and fever were significant and independent negative predictors of survival. Growth failure, persistent oral candidosis, hepatitis, and cardiopathy were associated in univariate analysis with significantly shorter survival. Our findings suggest that the outlook for children with perinatal HIV-1 infection is better than previously thought and that a new clinical staging system of single disease patterns is needed.

Anodic stripping voltammetry is applied to commercial tinplate samples at several sweep rates. The results are analyzed based on Brainina's theory of pure metal layer dissolution. It is concluded that there is no preferential dissolution of the alloy elements during anodic stripping voltammetry. The FeSn 2 alloy layer dissolves as a pure metal. The anodic voltammetry can be used as a characterization technique for commercial tinplate.