Optimizing biogas methanation over nickel supported on ceria-alumina catalyst: Towards CO2-rich biomass utilization for a negative emissions society.

Biogas methanation emerges as a prominent technology for converting biogas into biomethane in a single step. Furthermore, this technology can be implemented at biogas plant locations, supporting local economies and reducing dependence on large energy producers. However, there is a lack of comprehensive studies on biogas methanation, particularly regarding the technical optimization of operational parameters and the profitability analysis of the overall process. To address this gap, our study represents a seminal work on the technical optimization of biogas methanation obtaining an empirical model to predict the performance of biogas methanation. We investigate the influence of operational parameters, such as reaction temperature, H2/CO2 ratio, space velocity, and CO2 share in the biogas stream through an experimental design. Based on previous research we selected a nickel supported on ceria-alumina catalyst; being nickel a benchmark system for methanation process such selection permits a reliable data extrapolation to commercial units. We showcase the remarkable impact of studied key operation parameters, being the temperature, the most critical factor affecting the reaction performance (ca. 2 to 5 times higher than the second most influencing parameter). The impact of the H2/CO2 ratio is also noticeable. The response surfaces and contour maps suggest that a temperature between 350 and 450 °C and an H2/CO2 ratio between 2.5 and 3.2 optimize the reaction performance. Further experimental tests were performed for model validation and optimization leading to a reliable predictive model. Overall, this study provides validated equations for technology scaling-up and techno-economic analysis, thus representing a step ahead towards real-world applications for bio-methane production.

MGIS: managing banana (Musa spp.) genetic resources information and high-throughput genotyping data.

Database URL: https://www.crop-diversity.org/mgis/.

MRI evaluation of inflammatory activity in Crohn's disease.

OBJECTIVE: We wanted to assess the capability of MRI to quantitatively evaluate the therapeutic response to Crohn's disease (CD) relapse. SUBJECTS AND METHODS: Twenty patients with histologically proven CD were prospectively evaluated with MRI and ileocolonoscopy over a 2-year period. The MRI protocol included axial and coronal T2-weighted and contrast-enhanced T1-weighted sequences. MRI examinations were performed twice, once during an acute relapse of CD and the other at clinical remission. The terminal ileum and colon were divided into six segments/patient, and the endoscopy and histology findings were considered the standard of reference. These were compared on a segmental basis with the quantitative MRI findings regarding wall thickness and contrast enhancement. The results obtained in active and remission CD phases were likewise compared with the findings in 10 control subjects who underwent complete ileocolonoscopy for other reasons and had no pathological findings on ileocolonoscopy. RESULTS: Fifty three of 120 (44.2%) bowel segments showed pathologic changes on endoscopy and histology consistent with CD in active phase. On changing from the active disease phase to clinical remission, a significant decrease was observed in the wall thickness and contrast enhancement of the affected bowel wall. In the active phase of CD, the pathologic bowel segments presented with significantly greater contrast enhancement and wall thickness values compared with the healthy segments of CD and controls. On converting clinically into remission, contrast enhancement tended to normalize, whereas bowel wall thickness remained increased compared with the controls. CONCLUSION: MRI is able to detect pathologic bowel segments in CD, as it allows the measurement of significant variations in wall thickness and contrast enhancement on changing from the active phase of the disease to remission.

Guía terapéutica en atención primaria basada en la evidencia, 2. ª edición: una obra honesta y práctica / Therapeutic guide to Primary Care based on the evidence, 2nd edition: an honest and practical work

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[Infectious endocarditis in parenteral drug addicts: study of 57 cases]. / Endocarditis infecciosa en adictos a drogas por vía parenteral: estudio de 57 casos.

We present 57 cases of infectious endocarditis (IE) in 51 parenterally drug addicts (PDA) admitted at the Internal Medicine Service of the Hospital Clínico of Valencia between January ist, 1988 and January 15th, 1992. The disease affected young patients, 84% of them being HIV-1+ and 86% presenting CD4+ lymphocytes lower than 200 cells/mm3. Fever was the most constant symptom, with radiological disorders and presence of vegetations by echocardiogram in 65% and 53% of episodes, respectively, and affectation of the tricuspid valve in 59% of patients. The diagnosis of endocarditis was definitive in 51% of cases, possible in 15% and probable in 22%, being cardiac failure the most severe complication, present in 23% of episodes. The detection of significant valve regurgitation in patients with IE and without developing cardiac failure is not predictive of future complications, nor its absence identifies patients with a favourable prognosis. Staphylococcus aureus was the most frequently isolated germ (48%), being methicillin-resistant in 15% of cases and with a slower response to the treatment with vancomycin than the methicillin-sensitive. Five patients died, all of them with CD4+ lower than 50 cells/mm3, which may have a predictive value in the follow-up of these patients.

[Pneumocystis carinii pneumonia]. / La neumonía por Pneumocystis carinii.

We present twelve cases of Pneumocystis Carinii Pneumonia (PCP) hospitalized at the Internal Medicine Service of the Hospital Clínico de Valencia between 1989 and 1990. All patients were infected by HIV-1, with ages between 25 and 32 years, with circulating CD4 lymphocytes lower than 25% or 200 cells per cubic millimeter and with positive p24 antigen. Ten of them were parenterally drug addicts and two of them, homosexuals. Diagnosis was made by fibrobronchoscopy (FB) with bronchoaspiration (BAS) and bronchoalveolar lavage (BAL), or sputum induced by physiological serum aerosol at three per cent, using in both cases blue tinction with toluidine 0 of the samples obtained. Given the foreseeable increase of this disease in our country, we stress the risk of a potential change in its clinical spectrum, affecting new population groups, mainly the elderly, as well as the development of new early diagnosis techniques and the emergence of new treatments, including corticotherapy.

[Generalized persistent lymphadenopathy syndrome in parenteral drug addicts. Lymph node biopsy study of 41 patients]. / Síndrome de la linfoadenopatía persistente generalizada en adictos a drogas por vía parenteral. Estudio biópsico ganglionar de 41 pacientes.

Of a total of 41 VIH positive patients, parenteral drug addicts, with persistent generalized lymphadenopathy syndrome, we performed 43 lymph-node biopsies. In two sequential biopsies, 2 and 12 months respectively after the first biopsy, were carried-out. After a clinical follow-up (ranging between 4-28 months) 12 patients (24.3%) were qualified as SIDA cases according to CDC-1987 criteria. Lymph-node biopsy was of diagnostic or prognostic value in 16.27% and in 6.97% respectively. Upon comparing histological types and peripheral lymphocyte subsets it was demonstrated how the forms of major morphological deterioration tend to associate with a lower number of OKT4+ lymphocytes and a lower relation OKT4+/OKT8+.