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Hydrogen sulfide is one of the main waste products of the petrochemical industry; it is produced by the catalytic hydrodesulfurization processes (HDS) of the hydrocarbon feedstocks, and it is a byproduct from the sweetening of sour natural gas and from the upgrading of heavy oils, bitumen, and coals [...]

Ceria-supported vanadium catalysts were studied for H2S removal via partial and selective oxidation reactions at low temperature. The catalysts were characterized by N2 adsorption at 77 K, Raman spectroscopy, X-ray diffraction techniques, and X-ray fluorescence analysis. X-ray diffraction and Raman analysis showed a good dispersion of the V-species on the support. A preliminary screening of these samples was performed at fixed temperature (T = 327 °C) and H2S inlet concentration (10 vol%) in order to study the catalytic performance in terms of H2S conversion and SO2 selectivity. For the catalyst that exhibited the higher removal efficiency of H2S (92%) together with a lower SO2 selectivity (4%), the influence of temperature (307–370 °C), contact time (0.6–1 s), and H2S inlet concentration (6–15 vol%) was investigated.

P-nitrophenol (PNP) is a toxic organic pollutant and it is difficult to remove from wastewater by means of conventional treatment processes. Therefore, effective and low cost alternative water treatment technologies are required. In the last years there has been a growing interest in advanced oxidation processes involving semiconductor mediated photocatalysis because the process mineralizes many toxic organic pollutants to carbon dioxide and water at ambient temperature under UV light. The aim of this work is to synthetize ZnS photocatalyst starting from formerly ZnO prepared with different precursors such as zinc sulphate and zinc nitrate by means of precipitation method. ZnS was then obtained by sulfuration of ZnO particles. The sulfuration step was carried out at 450°C in presence of N2 gaseous stream containing H2S at 5 vol%. The prepared photocatalysts were characterized from chemical-physical point of view using different techniques (XRD, BET, UV-vis DRS, Raman). The photocatalytic tests were carried out in a recirculating batch cylindrical photoreactor irradiated by a UV-LEDs strip (nominal power of 12W/m and wavelength emission peak at about 365 nm) surrounding the external surface of the reactor. The experimental results evidenced that the optimal sample is ZnS obtained from the sulphuration of ZnO synthetized by zinc sulphate. In particular, this sample was able to achieve about 51% PNP degradation after 240 min of UV light irradiation.

The hydrolysis of carbonyl sulfide (COS) was studied in a gas-liquid reactor at room temperature and ambient pressure in presence of alkanolamines, such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA) and diisopropylamine (DIPA). The activity and stability of the different amines was investigated at fixed COS inlet concentration and reaction volume. The highest removal efficiency of COS was obtained in presence of DEA aqueous solution (25 %), while the lowest COS conversion was observed with the tertiary amine MDEA (< 10 %). A greater COS removal was obtained in presence of the higher reaction volume (400 cm3) that was equal to 25 % for DEA and 26 % for DIPA, respectively. Finally, the evaluation of the kinetic constant for the COS hydrolysis reaction with DEA was performed.

Since the late 1980s, the scientific community has been attracted to microwave energy as an alternative method of heating, due to the advantages that this technology offers over conventional heating technologies. In fact, differently from these, the microwave heating mechanism is a volumetric process in which heat is generated within the material itself, and, consequently, it can be very rapid and selective. In this way, the microwave-susceptible material can absorb the energy embodied in the microwaves. Application of the microwave heating technique to a chemical process can lead to both a reduction in processing time as well as an increase in the production rate, which is obtained by enhancing the chemical reactions and results in energy saving. The synthesis and sintering of materials by means of microwave radiation has been used for more than 20 years, while, future challenges will be, among others, the development of processes that achieve lower greenhouse gas (e.g., CO2) emissions and discover novel energy-saving catalyzed reactions. A natural choice in such efforts would be the combination of catalysis and microwave radiation. The main aim of this review is to give an overview of microwave applications in the heterogeneous catalysis, including the preparation of catalysts, as well as explore some selected microwave assisted catalytic reactions. The review is divided into three principal topics: (i) introduction to microwave chemistry and microwave materials processing; (ii) description of the loss mechanisms and microwave-specific effects in heterogeneous catalysis; and (iii) applications of microwaves in some selected chemical processes, including the preparation of heterogeneous catalysts.

A supported metal sulphide - based catalyst was prepared and studied for the reaction of H2S oxidative decomposition to produce simultaneously H2 and sulphur. The study was carried out by investigating different operating conditions such as H2S inlet concentration (10 - 40 vol%), O2/H2S feeding molar ratio (0.2 - 0.35) and reaction temperature (700 – 1,100 °C) with the aim to minimize SO2 selectivity and maximize the H2 yield together with a good H2S conversion. From the preliminary experimental tests, it was possible to identify the optimal operating conditions (T = 1,100 °C, H2S = 10 vol%, O2/H2S = 0.2), suitable to obtain a high H2S conversion (59 %), a good H2 yield (20 %) and depressing the SO2 selectivity (< 0.05 %). The catalyst showed a good activity and stability during 10 h of time on stream without any deactivation phenomena. The presence of the catalyst resulted in an improvement of both H2S decomposition reaction to produce H2 and partial oxidation reaction to sulphur, realizing simultaneously the abatement of SO2 by the Claus reaction.

Cordierite honeycomb structured catalysts were studied for the reaction of H2S decomposition in the presence of oxygen to obtain H2 and sulphur. An Al2O3-based washcoat was deposited on the honeycomb monolith by a dip-coating procedure. In particular, three different washcoat percentages (15, 20 and 30 wt%) were deposited on the structured carrier and the obtained samples were characterized by N2 adsorption and SEM analysis. The evaluation of the catalytic performance of the three samples was carried out at two different temperatures (1000 °C and 1100 °C). The sample with 30 wt% washcoat content showed the lowest SO2 selectivity at 1000 °C (2S conversion and H2 yield values were very similar to those achieved for the samples at 15 and 20 wt% washcoat loading. Based on these results, additional tests were carried out on the catalyst with 30 wt% Al2O3-based washcoat loading, varying the contact time and the H2S inlet concentration to identify the operating conditions that minimize the SO2 formation, obtaining good H2S conversion and H2 yield. The comparison of the structured catalyst with the powder alumina sample has shown the same catalytic performance, exhibiting lower SO2 selectivity.

En Ecuador, el sector turístico y todo lo que este engloba, fue uno de los más afectados por la Covid-19. Por ello, el objetivo del trabajo fue analizar la percepción de la población sobre los cambios provocados por esta pandemia, en el turismo comunitario y conocimientos ancestrales, en el cantón Arajuno. Utilizando el método cualitativo bajo un enfoque de género, se recopiló información, a través de entrevistas y observación participativa, el análisis e interpretación de datos se los llevó a cabo mediante un análisis de discurso con la ayuda del software ATLAS ti. Los resultados muestran que las mujeres tomaron iniciativa para desarrollar y consolidar el turismo comunitario y sus conocimientos ancestrales. Este es un claro ejemplo de actividades que muestran interés por generar equidad y bienestar social, económico y ambiental de su comunidad colectiva.

Coagulase-negative staphylococci (CoNS) are commensal on human body surfaces and, for years, they were not considered a cause of bloodstream infection and were often regarded as contamination. However, the involvement of CoNS in nosocomial infection is increasingly being recognized. The insertion of cannulas and intravascular catheters represents the primary source of CoNS entry into the bloodstream, causing bacteremia and sepsis. They owe their pathogenic role to their ability to produce biofilms on surfaces, such as medical devices. In this study, we evaluate the adhesive capacity of CoNS isolated from blood cultures by comparing a spectrophotometric phenotypic assay with genotypic analysis based on the evidence of the ica operon. We retrospectively reviewed the database of CoNS isolated from blood cultures from January to December 2021 that were considered responsible for 361 bloodstream infections. Eighty-nine CoNS were selected among these. Our data show that Staphylococcus epidermidis was the predominant species isolated, expressing greater adhesive capacities, especially those with the complete operon. Knowledge of the adhesive capabilities of a microorganism responsible for sepsis can be useful in implementing appropriate corrective and preventive measures, since conventional antibiotic therapy cannot effectively eradicate biofilms.

Abstract This study assessed the relationship between the recharge of the unconfined sedimentary Adamantina Aquifer and its discharge into the Batalha River in a small basin of 125 km2 that drains the municipalities of Bauru, Agudos and Piratininga (SP, Brazil). According to the Eckhardt Flow Separation Filters and Soil Moisture Accounting Procedure methods, the recharge was 312.6 mm/yr and 232.0 mm/yr, respectively; and 286.2 mm/yr to the modified-Thornthwaite method for the 2000–2018 period. Recharge values prone to converge as more extended periods are analyzed (ideally 18 years) because the sensitivities to a specific parameter tend to be mitigated over time. With the integration of the methods, we established how changes in land-use impact the aquifer recharge and, thus, the discharges and the behavior of the river’s recession curve. Areas used to cultivate sugar cane (193 mm/yr), eucalyptus (150 mm/yr), or to urbanization (72 mm/yr) exert control over aquifer recharge even more than topography or type of soil. The combined and integrated use of three simple techniques allows them to be used for land-use planning and assessment of water availability in small hydrographic basins when hydrological data are scarce.

Mycobacterium chimaera (MC) is an environmental, slowly growing, non-tuberculous mycobacterium (NTM) belonging to Mycobacterium avium complex (MAC), which recently has been linked to severe cardiovascular infections following open heart and vascular surgery. The majority of the diagnostic laboratory tests used in routine are not able to distinguish MC from M. intracellulare (MI), because of the great genetic similarity existing between these two species. The Genotype Mycobacterium NTM-DR™ represents a valid method to differentiate between these species, but it is expensive, requiring also specialized personnel. Recently, MALDI-TOF MS has been proposed to identify relevant NTM. However, a software implementation is required to distinguish between MC and MI, presenting the two microorganisms’ overlapping spectra. The present study evaluates the feasibility of applying a MALDI-TOF logarithmic-based analysis in the routine of a clinical microbiology laboratory, and proposes an easy-to-use template spreadsheet to make the results quickly interpretable. The protocol was previously validated through the identification of 87 strains of MC/MI collected from clinical and environmental samples, and it was identified using the GenoType Mycobacterium NTM-DR™ and/or WGS. The proposed protocol provides accurate identification for the isolates tested; moreover, it is less expensive and more rapid than sequencing methods and can be implemented with minimum effort.

O presente artigo busca a partir da análise de dados do Censo Agropecuário do IBGE, 2006, contribuir para o melhor entendimento do papel das águas subterrâneas na oferta de água nos estabelecimentos agropecuários do Brasil. É feita uma apresentação das fontes de águas disponíveis nestes estabelecimentos, chamando-se a atenção para o papel das águas subterrâneas. Mostra-se que 37% dos estabelecimentos agropecuários não possuem nenhuma fonte de água e destaca-se a importância que iniciativas da sociedade civil e governamentais têm para o enfrentamento desta situação de Insegurança Hídrica e por fim destaca-se que o Censo Agropecuário pode se tornar em uma importante fonte de informações para melhor gerir a água no meio rural.

Há tempos a população do semiárido nordestino sofre com problemas de abastecimento de água, decorrentes dos períodos de seca. Alternativas para este cenário foram criadas na forma de políticas públicas, como a construção de açudes, captação de recursos hídricos subterrâneos, transposição de rios e captação de água através de cisternas. No Estado do Ceará a situação é grave. Com pluviosidade média anual de 800 mm (FUNCEME) e extensos períodos sem chuva, suas águas subterrâneas têm alta salinidade, provocada pela lixiviação superficial e transporte para o reservatório, ou dissolução interna no próprio aquífero (Santiago et al., 2000). Cerca de 85% do território do estado cearense pertence ao semiárido (Roberto e Silva, 2010), sendo ausente em algumas porções da região litorânea. Nesse contexto, o conhecimento sobre a hidrogeologia é fundamental para o melhor aproveitamento das águas subterrâneas. Em regiões onde as fraturas são mais permeáveis, estudos interdisciplinares empregando geologia estrutural, geomorfologia e interpretação de imagens de sensores remotos têm auxiliado no conhecimento desses aquíferos, muitas vezes mostrando que existem correlações entre padrões geomorfológico-estruturais e a produtividade de poços.

O semiárido cearense registrou um dos seus períodos mais agudos de seca, que durou 6 anos, findo em 2017. Assim, a água subterrânea tem sido umas das alternativas para suprir a demanda hídrica da população e, nesse contexto, a hidrogeologia é ferramenta fundamental, principalmente porque a maior parte dessa área é localizada em aquíferos fraturados. A presente pesquisa busca estabelecer e diferenciar áreas ou feições mais propícias a poços, através da análise e correlação da tectônica cenozóica, dos diferentes grupos de rochas e dos padrões geomorfológicos-estruturais, com a produtividade de poços nos municípios de Pedra Branca e Tauá (CE). A avaliação dos dados hidrogeológicos, cedidos pela Companhia de Gestão dos Recursos Hídricos (COGERH), mostra valores de capacidade específica baixos, com mediana 0,03 m³/h/m e 31% de poços secos, e que os dois municípios possuem características distintas de produção e de distribuição de dados. Uma avaliação inicial não tem mostrado uma relação entre lineamentos em imagem de satélite e melhores produções em poços, indicando que o clima ou a própria geologia local controlam a circulação de água no aquífero de forma ainda não compreendida; que poderá ser superada com técnicas envolvendo a neotectônica.

ABSTRACT The study area is located in the state of Minas Gerais, Brazil, among the municipalities of Pedro Leopoldo, Matozinhos, and Sete Lagoas, with Velhas River as the eastern boundary. It is located in the São Francisco Craton, where carbonated argillo-arenaceous sediments are emplaced giving origin to the Bambuí Group, in the São Francisco Basin. Despite the geological knowledge previously developed, the region needs work on integration and detailing of such information. For this reason, the main objective was to contribute to the quality of the geologic cartography, the spatial distribution, and the structural framework geometry. Thus, geologic mapping, aerial photography interpretation, and evaluation of 270 lithologic well profiles were carried out. It was possible to establish a new geologic perspective of the region by obtaining the detailed geologic map of the municipality of Sete Lagoas, 14 geologic cross sections, and a geologic conceptual model. The study showed that the area is within a basin border, presenting a geometry conditioned by horst and graben system controlled by faulting. This structural feature displaced stratigraphic sequences positioning them side by side with lithologic sequences with different ages.

We assessed the clinical relevance and performed molecular characterization of 36 multidrug-resistant strains of Corynebacterium striatum. Pulsed-field gel electrophoresis confirmed a single clone, possessing erm(X), tetA/B, cmxA/B, and aphA1 genes, but few related subclones. This strain is emerging as a pathogen in Italy.

The aim of this paper is to present the trans-cultural adaptation and reliability of the Sense of Coherencescale (SOC-13 from Antonovsky) into Portuguese language using a sample of mothers of preschool children. The originally validated scale demonstrated a low return percentage and high number of extreme answers when applied to mothers of preschool children selected by convenience sampling in Brazil. Adaptations were made through cognitive interviews and involved rewording items, the usage of five rather than seven alternatives and the insertion of middle anchoring phrases. Three independent samples took part in the study for the psychometric tests. These samples consisted of one group of 36 and another of 38 mothers selected by convenience, as well as an additional group of 546 mothers randomly selected from the city of Belo Horizonte, Brazil. Instrument reliability was accessed by internal consistency, testretest and item-to-total-score correlations with each of the three samples, respectively. Findings indicate that the adapted scale is comprehensible and obtained a greater response rate than the originally validated scale. Internal consistency increased from 0.67 for the original scale to 0.71 for the adapted scale. This value was extended to 0.80 in the test with the randomly selected sample. Medium weighted Kappa coefficients were 49.5%. The Spearman test demonstrated that the questions were correlated with total SOC scores. Results indicate that the adapted scale is valid and consistent for mothers of preschool children from different social classes.

Words are built from smaller meaning bearing parts, called morphemes. As one word can contain multiple morphemes, one morpheme can be present in different words. The number of distinct words a morpheme can be found in is its family size. Here we used Birth-Death-Innovation Models (BDIMs) to analyze the distribution of morpheme family sizes in English and German vocabulary over the last 200 years. Rather than just fitting to a probability distribution, these mechanistic models allow for the direct interpretation of identified parameters. Despite the complexity of language change, we indeed found that a specific variant of this pure stochastic model, the second order linear balanced BDIM, significantly fitted the observed distributions. In this model, birth and death rates are increased for smaller morpheme families. This finding indicates an influence of morpheme family sizes on vocabulary changes. This could be an effect of word formation, perception or both. On a more general level, we give an example on how mechanistic models can enable the identification of statistical trends in language change usually hidden by cultural influences.

Morphemes are the smallest meaningful parts of words and therefore represent a natural unit to study the evolution of words. To analyze the influence of language change on morphemes, we performed a large scale analysis of German and English vocabulary covering the last 200 years. Using a network approach from bioinformatics, we examined the historical dynamics of morphemes, the fixation of new morphemes and the emergence of words containing existing morphemes. We found that these processes are driven mainly by the number of different direct neighbors of a morpheme in words (connectivity, an equivalent to family size or type frequency) and not its frequency of usage (equivalent to token frequency). This contrasts words, whose survival is determined by their frequency of usage. We therefore identified features of morphemes which are not dictated by the statistical properties of words. As morphemes are also relevant for the mental representation of words, this result might enable establishing a link between an individual's perception of language and historical language change.

O município de Sete Lagoas (MG) tem enfrentado um forte e acelerado crescimento populacional e econômico, agravando problemas decorrentes à demanda por água, extraída de um sistema aquífero cárstico, como associados à restrição no abastecimento público, à contaminação do solo e do aquífero, e às reduções de vazão aos cursos de água superficial. Tal estudo tem como objetivo avaliar os recursos hídricos subterrâneos, de forma quantitativa e qualitativa, de modo a identificar e delimitar áreas de recarga dos aquíferos, fontes potenciais de contaminações e áreas de risco geológico no município. Para isso, estão sendo executados estudos de cadastramento e ensaios de poços tubulares; de sensoriamento remoto, mapeamento geológico, isótopos ambientais e, por fim, criação de sistemas para a gestão de recursos hídricos do município.

A 50-year-old man, pentathlete and fond of salmon fishing, after returning from Alaska was referred to our Division for an erythematous and indolent lesion on the right thigh gradually enlarging from the right knee to the right rear and the buttock.The patient was clinically diagnosed with figurate erythema. Laboratory analysis demonstrated a moderate leukocytosis and hypergammaglobulinemia, accompanied by serological markers of past contact with noted EBV and CMV.A “punch” biopsy of the edge of the lesion showed a superficial and deep perivascular and interstitial infiltrate of lymphocytes, eosinophiles and a few plasma cells, consistent with a borrelial infection. Lyme serology (IFI) suggested a questionable borderline positivity; subsequent investigations by ELISA and Western Blot were both positive, leading to the diagnosis of erythema chronicum migrans in course of borreliosis.The diagnosis was further confirmed by positive PCR for Borrelia burgdorferi sensu lato. The erythema resolved after a 2-week doxycycline treatment (2x100 mg die). The amplification product (16S rDNA gene) obtained from skin biopsy was sequenced using standard ABI technology, and confirmed the identification of a member of B. burgdorferi sensu lato (sl) complex. Since this sequence was not useful to identify the genospecies, further studies were conducted employing a nested PCR targeted on the internal transcribed spacer (ITS) of B. burgdorferi, following a protocol previously described (1). The ITS sequence showed 100% identity with B. afzelii, a species not reported from North America, thus prompting us to conclude that the patient was not infected by B. afzelii during the fishing trip in Alaska.