Exergo-economic comparison of waste heat recovery cycles for a cement industry case study

José J. Fierro ORCID ID: https://orcid.org/0000-0003-2306-611X; Carlos A. Marenco-Porto ORCID ID: https://orcid.org/0000-0002-2969-5040; César Nieto-Londoño ORCID ID: https://orcid.org/0000-0001-6516-9630; Ana Escudero-Atehortua ORCID ID: https://orcid.org/0000-0003-2962-4426; Hussam Jouhara ORCID ID: https://orcid.org/0000-0002-6910-6116; Luiz C. Wrobel ORCID ID: https://orcid.org/0000-0001-6702-0178.Copyright © 2022 The Authors. This work evaluates the performance regarding exergo-economic and emissions requirements of Waste Heat Recovery configurations (Organic Rankine cycle, Trilateral flash cycle, and Kalina cycle) under different operating conditions and working fluids. It was found that the best economic performance is presented by the Organic Rankine cycle that operates with Cyclo-Pentane and has two intermediate heat exchangers since it pushes the expansion temperature up while allowing a higher heat input to the cycle. As a result, it delivers 6.2 MW with a net present value, the net present value of 0.74 million dollars, saving up to 11480 tonnes of carbon dioxide per year. This performance far exceeds that obtained in the previous work, around 50% higher net-work with 80% higher net present value, and constitutes the best alternative in terms of performance to recover waste heat from the source evaluated. Regarding the Trilateral flash cycle, it can be stated that the net work and the exergetic performance are independent of the working fluid as long as there is not a very large volume change in the expander. The Kalina cycle presents slight exergy destruction, but the power delivered does not compensate for the high total capital cost due to the high pressures that must be handled, 55–120 bar, compared to the Organic Rankine cycle, 4–40 bar. An approach was made to more realistic cases where the methodology used facilitates selecting the best alternative when there is a budget restriction using the total capital cost and net work alternatively like a fixed requirement and net present value as the primary decision criterion.This research is funded by the The Royal Academy of Engineering through the Newton-Caldas Fund IAPP18-19\218 project that provides a framework where industry and academic institutions from Colombia and the UK collaborate in the heat recovery in large industrial systems

Minor psychiatric disorders among Brazilian ragpickers: a cross-sectional study

BACKGROUND: Ragpickers are informal workers who collect recyclable materials to earn a small wage. Their life and working conditions are extremely difficult. We examined minor psychiatric disorders (MPD) among a cohort of ragpickers in Pelotas, a city in southern Brazil. METHODS: Ragpickers were matched by sex, age, and years of schooling with a sample of non-ragpickers from the same poor neighborhoods. The cross-sectional study gathered data by interview on 990 individuals in 2004. MPD were assessed using a standard self-reporting questionnaire, the SRQ-20. RESULTS: The prevalence of MPD among ragpickers was 44.7%, higher than reported by neighborhood controls (33.6%; p < 0.001). MPD were more common among females, those of lower economic level, smokers and alcoholics. Among occupational characteristics, MPD prevalence was associated with frequent static postures, low job satisfaction and recent work accidents. CONCLUSION: Ragpickers more frequently report MPD than other poor workers living in the same neighborhoods, with many of the same life conditions. Improving the work lives of these precarious workers should address not only the physical hazards of their jobs but their mental and emotional health as well

Aging of the mammalian gastrointestinal tract: a complex organ system

Gastrointestinal disorders are a major cause of morbidity in the elderly population. The gastrointestinal tract is the most complex organ system; its diverse cells perform a range of functions essential to life, not only secretion, digestion, absorption and excretion, but also, very importantly, defence. The gastrointestinal tract acts not only as a barrier to harmful materials and pathogens but also contains the vast number of beneficial bacterial populations that make up the microbiota. Communication between the cells of the gastrointestinal tract and the central nervous and endocrine systems modifies behaviour; the organisms of the microbiota also contribute to this brain–gut–enteric microbiota axis. Age-related physiological changes in the gut are not only common, but also variable, and likely to be influenced by external factors as well as intrinsic aging of the cells involved. The cellular and molecular changes exhibited by the aging gut cells also vary. Aging intestinal smooth muscle cells exhibit a number of changes in the signalling pathways that regulate contraction. There is some evidence for age-associated degeneration of neurons and glia of the enteric nervous system, although enteric neuronal losses are likely not to be nearly as extensive as previously believed. Aging enteric neurons have been shown to exhibit a senescence-associated phenotype. Epithelial stem cells exhibit increased mitochondrial mutation in aging that affects their progeny in the mucosal epithelium. Changes to the microbiota and intestinal immune system during aging are likely to contribute to wider aging of the organism and are increasingly important areas of analysis. How changes of the different cell types of the gut during aging affect the numerous cellular interactions that are essential for normal gut functions will be important areas for future aging research

Conservation and divergence within the clathrin interactome of <i>Trypanosoma cruzi</i>

Trypanosomatids are parasitic protozoa with a significant burden on human health. African and American trypanosomes are causative agents of Nagana and Chagas disease respectively, and speciated about 300 million years ago. These parasites have highly distinct life cycles, pathologies, transmission strategies and surface proteomes, being dominated by the variant surface glycoprotein (African) or mucins (American) respectively. In African trypanosomes clathrin-mediated trafficking is responsible for endocytosis and post-Golgi transport, with several mechanistic aspects distinct from higher organisms. Using clathrin light chain (TcCLC) and EpsinR (TcEpsinR) as affinity handles, we identified candidate clathrin-associated proteins (CAPs) in Trypanosoma cruzi; the cohort includes orthologs of many proteins known to mediate vesicle trafficking, but significantly not the AP-2 adaptor complex. Several trypanosome-specific proteins common with African trypanosomes, were also identified. Fluorescence microscopy revealed localisations for TcEpsinR, TcCLC and TcCHC at the posterior region of trypomastigote cells, coincident with the flagellar pocket and Golgi apparatus. These data provide the first systematic analysis of clathrin-mediated trafficking in T. cruzi, allowing comparison between protein cohorts and other trypanosomes and also suggest that clathrin trafficking in at least some life stages of T. cruzi may be AP-2-independent

Factors associated to infection by Toxoplasma gondii in pregnant women attended in Basic Health Units in the city of Rolândia, Paraná, Brazil

The aim of the present work was to determine the prevalence of IgG and IgM anti-Toxoplasma gondii antibodies and the factors associated to the infection in pregnant women attended in Basic Health Units in Rolândia, Paraná, Brazil. The sample was divided in two groups: group I (320 pregnant women who were analyzed from July 2007 to February 2008) and group II (287 pregnant women who were analyzed from March to October 2008). In group I, it was found 53.1% of pregnant women with IgG reactive and IgM non-reactive, 1.9% with IgG and IgM reactive, 0.3% with IgG non-reactive and IgM reactive and 44.7% with IgG and IgM non-reactive. In group II, it was found 55.1% with IgG reactive and IgM non-reactive and 44.9% with IgG and IgM non-reactive. The variables associated to the presence of IgG antibodies were: residence in rural areas, pregnant women between 35-40 years old, low educational level, low family income, more than one pregnancy, drinking water which does not originate from the public water supply system and the habit of handling soil or sand. Guidance on primary prevention measures and the quarterly serological monitoring of the pregnant women in the risk group are important measures to prevent congenital toxoplasmosis