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The dissociation constant is a quantitative measure of the strength of an acid in solution. This study examines dissociation constant for the series substituted acids like Ortho-alkoxy-4-formylbenzoic acid. The use of (2-methoxy ethanol) as a solvent contributed to the study expected to form free ions or solvent separated ion pair which has been studied with the use conductometric method at different temperatures ranged from 293.15 to 318.15K. The study aims at figuring out dissociation constant, equivalent conductance at infinity dilution, and Walden product by minimization technique using Fuoss-Hsia for both (Modified and Complete) equations. It has been found in the results that the calculated values based on statistical sum square (different between practical and theoretical values) is equivalent conductance at infinity dilution and dissociation constant. It has also been observed that increase the temperature leads to the increase of the molar conductance at infinity dilution, and the increase in association. Moreover, the substituted alkoxy group also affected dissociation of compounds. In this study, the thermodynamic parameters (Ho, Go and So) have also been evaluated and discussed. Finally, the effect of substituent groups on rate of dissociation was studied and explained with agreement to the principles of mesomeric(M) and Inductive effect(I) of substituent groups on dissociation constant.

Alizarin Red (AR) is one of the most colored hazardous industrial dye. For effective removal of AR, a new sorbent of modified heterocyclic- magnetite chitosan nanocomposite (AOC@MC) was synthesized and characterized by FTIR, TGA, and SEM-EDX Effect of contact time, pH, adsorbent dosage, initial Alizarine Red concentration and temperature was investigated. The maximum AR removal was 98.9% and attained at optimum conditions which were pH = 3.0, contact time = 50 min., and adsorbent dosage = 0.03 g/L. The €findings revealed that at pH 3 and 30◦ C, the maximum adsorption capacity was approximately 162 mg/g. Within 50 min, equilibrium adsorption was attained. A pseudo-second-order equation might be used to fit the kinetic data that was acquired at the optimal pH level of 3. Langmuir adsorption isotherms could accurately represent the adsorption process. The antimicrobial properties of the functionalized sorbent and its heterocyclic base are characterized by determining the zone of inhibition (ZOI) against Staphylococcus aureus and Klebsiella pneumonia as a model for Gram-positive and Gram-negative bacteria respectively. The modified chitosan sorbent (AOC@MC) exhibits promising activity with clear zones of 20.1 ± 0.2 and 17.6 ± 0.4 mm for S. aureus and K. pneumonia respectively. Whereas, the synthesized heterocyclic compounds didn’t show antibacterial activity toward tested strains. Overall, the modified compound was efficient on AR dye removal and antibacterial activity compared to unmodified and heterocyclic compounds.

Over the last few years, various industries have released wastewater containing high concentrations of dyes straight into the ecological system, which has become a major environmental problem (i.e., soil, groundwater, surface water pollution, etc.). The rapid growth of textile industries has created an alarming situation in which further deterioration to the environment has been caused due to substances being left in treated wastewater, including dyes. The application of activated carbon has recently been demonstrated to be a highly efficient technology in terms of removing methylene blue (MB) from wastewater. Agricultural waste, as well as animal-based and wood products, are excellent sources of bio-waste for MB remediation since they are extremely efficient, have high sorption capacities, and are renewable sources. Despite the fact that commercial activated carbon is a favored adsorbent for dye elimination, its extensive application is restricted because of its comparatively high cost, which has prompted researchers to investigate alternative sources of adsorbents that are non-conventional and more economical. The goal of this review article was to critically evaluate the accessible information on the characteristics of bio-waste-derived adsorbents for MB’s removal, as well as related parameters influencing the performance of this process. The review also highlighted the processing methods developed in previous studies. Regeneration processes, economic challenges, and the valorization of post-sorption materials were also discussed. This review is beneficial in terms of understanding recent advances in the status of biowaste-derived adsorbents, highlighting the accelerating need for the development of low-cost adsorbents and functioning as a precursor for large-scale system optimization.

Background and objectiveHigh quality evidence-based clinical practice guidelines (CPGs) have a major impact on the appropriate diagnosis and management and positive outcomes. The evidence-based healthcare for patients with attention deficit hyperactive disorder (ADHD) is challenging. The objective of this study was to appraise the quality of published CPGs for ADHD.MethodsA systematic review was conducted for ADHD CPGs using CPG databases, DynaMed, PubMed, and Google Scholar. The quality of each included CPG was appraised by three independent appraisers using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) instrument.ResultsSix CPGs were critically reviewed. The AGREE II standardized domain scores revealed variation between the quality of these CPGs with the National Institute of Health and Care Excellence (NICE), University of Michigan Health System, and American Academy of Pediatrics CPGs as the top three. Overall, the recommendations for management of ADHD were similar in these CPGs.ConclusionsReporting of CPG development is often poorly documented. Guideline development groups should aim to follow the AGREE II criteria to improve the standards and quality of CPGs. The NICE CPG showed the best quality. Embedding the AGREE II appraisal of CPGs in the training and education of healthcare providers is recommended. The protocol for this study was published in PROSPERO (International prospective register of systematic reviews). Link: http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42017078712 and is additionally available from protocols.io. Link: https://dx.doi.org/10.17504/protocols.io.q27dyhn.

When designing a bridge it is of high importance that the geometry for the cross section is optimized for the structure. This is partly due to the influence of the amount of material needed and its impact on the budget and environment. The influence of choosing the right amount of each material lies in the unit-price of the different material, where they can differ significantly. The Swedish Transport Administration, Trafikverket, has ordered the construction of Stockholm Bypass which is one of Swedens largest infrastructure project and is valued to 27.6 billion SEK according to the price index of the year 2009. The infrastructure project is divided into multiple projects where one of them is assigned to Implenia and Veidekke through a joint venture (Joint venture Hjulsta, JVH) and is valued to nearly 800 MSEK. The reference bridge that is used in the analysis of the master’s thesis is a part of the project. The aim of this masters thesis was to analyze and compare the two construction methods, mov- able scaffolding system (MSS) and incremental launching for the reference bridge with respect to amount post-tensioning and slenderness. Furthermore, an economical comparison between the two construction methods was carried out based on the obtained results. The analysis of the MSS was carried out by modeling the reference bridge structure in the finite element software SOFiSTiK AG. The bridge was modeled with different cross section height, i.e. different slenderness where the optimal amount of post-tension tendons could be determined by iteration until stress conditions from the Eurocode were fulfilled. For the incremental launching method, a numerical analysis was performed. The optimal amount of required post-tensioning was evaluated in the construction stages and final stages with different construction heights i.e. different values of slenderness. A cost analysis was also performed where the aim was to analyze how the total cost of the construc- tion of the bridge would be influenced by the different slenderness of the bridge as a comparison for the two construction methods. This was done by dividing the costs into fixed costs and variable costs. The results showed that the structural rigidity had a large influence on the required amount of prestressing steel for both construction methods. In other words, the smaller the cross section the more prestressing steel was required. Incremental launching proved to require a much greater amount of (PT) tendons compared to the MSS although the identical cross sections and properties for both methods, except for the PT. The prestressing for incremental launching is generally by centrical prestressing during the construction stages. A intersection point was obtained in the cost analysis for the construction methods. The incremental launching was the cheaper solution for slenderness smaller than the intersection point at slenderness between 17 and 18. The MSS was cheaper than the incremental launching for slenderness larger than the intersection point. Vid dimensionering av tvärsektioner i broar är det av stor vikt att optimera geometrin avseende materialåtgång då mängden material har stor på verkan på ett projekts budget samt miljö. Eftersom konstruktioner ofta består av olika byggnadsmaterial gäller det vid optimering att välja byggnadsmaterialen genom optimerad proportionalitet. Förbifart Stockholm, beställt av Trafikverket, är ett av Sveriges största infrastrukturprojekt och värderas till 27,6 miljarder kronor enligt 2009 års prisnivå. Infrastrukturprojektet är uppdelat i flera mindre entreprenader eller så kallade etapper. Den entreprenad som omfattar trafikplats Hjulsta Södra har blivit tilldelat till Implenia och Veidekke genom ett konsortium (Jointventure Hjulsta, JVH) och värderas till cirka 800 miljoner kronor. Den förspända betongbro som byggs i trafikplats Hjulsta ligger till grund för analysen i detta examensarbete och har använts som referens under vår studie. Syftet med examensarbete var att analysera och jämföra två de två olika produktionsmetoderna, Movable scaffolding system (MSS) och etappvis lansering med hänsyn till erforderlig mängd förspänningskablar och slankhet. Vidare, baserat på erhållna resultat, utfördes en ekonomisk analys och jämförelse mellan produktionsmetoderna. Analysen av MSS utfördes genom att modellera brokonstruktionen i mjukvaruprogrammet SOFiSTiK AG som bygger på finita elementmetoder. Konstruktionen modellerades för olika slankheter, där slankheten definieras som kvoten mellan maximala spannlängden och brons tvärsnittshöjd. Spannlängden hölls konstant medan tvärsnittshöjden varierade för att erhålla olika slankheter. Den optimala slankheten bestämdes genom iterering av mängd förspänningskablar tills spänningsvillkoren var uppfyllda enligt Eurocode. För analysen av etappvis lansering utfördes en numerisk analys vars den optimala mängden förspänningskablar utvärderades i byggskedet (construction stages) samt i slutskedet (final stage). Analysen utfördes på samma sätt för de olika slankheterna. Slutligen genomfördes en konstandsanalys för de olika metoderna. Syftet var att jämföra hur den totala kostnaden för uppförandet av brokonstruktionen skiljde sig för de olika slankheterna. Jämförelsen genomfördes genom att dela upp de olika kostnaderna i fasta kostnader samt rörliga kostnader. Resultaten från analysen visade att den erforderliga mängd förspänningskablar som behövs i en förspänd betongbro är beroende av den strukturella styvheten i tvärsektionen. En högre slankhet, alltså lägre tvärsnittshöjd, ger lägre styvhet och därav mer erforderlig förspänningskablar. Etappvis lansering visade sig vara den metod som krävde mer mängd förspänningskablar. I resultaten för kostnadsanalysen uppmättes en skärningspunkt, för en slankhet mellan 17-18, mellan de två olika metoderna. För förspända betongbroar med slankhet lägre än skärningsupunkten vid 17-18 är etappvis lansering det billigare alternativet. För slankheter högre än 17-18 är MSS det mer ekonomiskt lönsamma alternativet.

The maritime domain of the East African Community (EAC) is affected by a number of maritime security threats, including piracy, armed robbery against ships and an ongoing maritime border dispute between Kenya and Somalia. Neither the EAC nor its member States have long-term and holistic maritime security policies. Maritime security is dealt with in an ad-hoc, case-by-case manner, mainly by individual States. This study investigates why the EAC is not taking a leading role in regional maritime security governance. The study has found that the lack of regional maritime security policies, more importantly maritime security strategy, and the absence of a maritime institutional framework at the Community level, appear to be major setbacks to regional maritime security efforts. Additionally, the EAC depends on its member States, inter-regional and international maritime security programmes which currently offer a significant boost to EAC maritime security governance. Nonetheless, an EAC maritime security strategy would formalise and customise all of these strategies to match with regional maritime security needs. Moreover, it would provide a forum for communication and cooperation among maritime stakeholders.

Pericardial cysts are rare benign congenital malformations, usually small, asymptomatic and detected incidentally on chest X-ray as a mass located in the right costophrenic angle. Giant pericardial cysts are very uncommon and produce symptoms by compressing adjacent structures. In this report, the authors present a case of a symptomatic giant pericardial cyst incorrectly diagnosed as dextrocardia on chest X-ray. Resumo: Os quistos pericárdicos são malformações congênitas benignas raras. Habitualmente. são de pequena dimensão, assintomáticos e detectados de forma acidental na telerradiografia de tórax, como uma massa localizada no ângulo costofrênico direito. Grandes quistos pericárdicos são ainda mais raros e produzem sintomas por compressão de estruturas adjacentes. Neste artigo, os autores apresentam um caso clínico de um quisto pericárdico gigante e sintomático previamente diagnosticado como uma dextrocardia em telerradiografia de tórax. Keywords: Pericardial cyst, Chest X-ray, Palavras-chave: Quisto pericárdico, Telerradiografia de tórax

Resumo: A eficácia ventilatória, avaliada por prova de esforço cardiorrespiratória (PECR), tem um importante valor prognóstico em doentes (dts) com insuficiência cardíaca crónica (ICC) por disfunção sistólica ventricular esquerda (DSVE). Os seus determinantes mantêm-se, contudo, controversos. Objectivo: Investigar a eventual correlação entre parâmetros de eficácia ventilatória, obtidos por PECR, e o valor do fluido torácico total (FTT), avaliado por bioimpedância eléctrica torácica (BET), em dts com ICC por DSVE. Métodos: Estudámos 120 dts com ICC por DSVE, referenciados ao nosso laboratório para PECR – 76% do sexo masculino, idade 52,1 ± 12,1 anos, 37% de etiologia isquémica, fracção de ejecção ventricular esquerda 27,6 ± 7,9%, 83% em ritmo sinusal, 96% sob iECA e/ou ARAII, 79% sob beta-bloqueante e 20% tratados com dispositivo de ressincronização cardíaca. Os dts efectuaram PECR, em tapete rolante, protocolo de Bruce modificado, sendo considerados para análise, como parâmetro de capacidade funcional, o consumo de oxigénio de pico (VO2p) e, como parâmetros de eficácia ventilatória, o declive (d) da relação entre ventilação minuto (VE) e produção de CO2 (VCO2) e o valor do VE/VCO2 no limiar anaeróbico (LANA). Os estudos por BET, média de 20 minutos de aquisição, foram efectuados após 15 minutos de repouso, em posição supina, imediatamente antes das PECR, sendo analisado o valor do FTT. Resultados: O valor do FTT variou entre 20,6 e 45,8 kOhm−1, média = 32,2, DP = 5,7, mediana = 32,7, o de VO2p entre 8,9 e 40,6 ml/kg/min, média = 21,0, DP = 6,2, mediana = 20,2, o do dVE/VCO2 entre 19,8 e 60,7, média = 30,7, DP = 7,9, mediana = 29,1 e o do VE/VCO2 no LANA entre 21 e 62, média = 33,1, DP = 7,5, mediana = 31,5. Por regressão linear, o FTT não se correlacionou com o VO2p – r = 0,05, p = 0,58 – mas apresentou correlação com os parâmetros de eficácia ventilatória analisados: r = 0,20, p = 0,032, r2 = 0,04 com dVE/VCO2 e r = 0,25, p = 0,009, r2 = 0.06 com VE/VCO2 no LANA. Conclusão: O FTT correlaciona-se com os parâmetros de eficácia ventilatória, avaliados por PECR, em dts com ICC por DSVE, o que indica que poderá ser um dos seus determinantes. Abstract: Ventilatory efficiency, evaluated by cardiopulmonary exercise testing (CPET), has considerable prognostic value in patients with chronic heart failure (CHF) due to left ventricular systolic dysfunction (LVSD). Its determinants nevertheless remain controversial. Aim: To investigate the possible correlation between parameters of ventilatory efficiency obtained by CPET and thoracic fluid content (TFC), assessed by thoracic electrical bioimpedance (TEB), in patients with CHF due to LVSD. Methods: We studied 120 patients with LVSD and CHF, referred to our laboratory for CPET: 76% male, age 52.1±12.1 years, 37% of ischemic etiology, left ventricular ejection fraction 27.6±7.9%, 83% in sinus rhythm, 96% receiving ACEIs and/or ARBs and 79% beta-blockers, and 20% treated with a cardiac resynchronization device. TEB studies were performed after 15 minutes of rest, prior to symptom-limited treadmill CPET, using the modified Bruce protocol. CPET-derived peak oxygen consumption (pVO2), the slope of the relationship between minute ventilation (VE) and carbon dioxide production (VCO2), VE/VCO2 at the anaerobic threshold (AT), and TFC assessed by TEB were considered for analysis. Results: TFC ranged between 20.6 and 45.8 kOhm−1, mean 32.2, SD = 5.7, median 32.7, pVO2 8.9–40.6 ml/kg/min, mean 21.0, SD 6.2, median 20.2, VE/VCO2 slope 19.8–60.7, mean 30.7, SD 7.9, median 29.1 and VE/VCO2 at AT 21–62, mean 33.1, SD 7.5, median 31.5. By linear regression, TFC did not correlate with pVO2 (r = 0.05, p = 0.58), but showed correlation with parameters of ventilatory efficiency: r = 0.20, p = 0.032, r2 = 0.04 for VE/VCO2 slope and r = 0.25, p = 0.009, r2 = 0.06 for VE/VCO2 at AT. Conclusion: TFC correlates with CPET parameters of ventilatory efficiency in patients with CHF due to LVSD, suggesting that it may be one of its determinants. Palavras-chave: Insuficiência cardíaca, Prova de esforço, Eficácia ventilatória, Cardiografia de impedância, Fluido torácico total, Keywords: Heart failure, Exercise testing, Ventilatory efficiency, Impedance cardiography, Thoracic fluid content