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Ohmic heating, also known as electrical resistance heating, is a novel process of pasteurization that has several advantages including homogeneous heating, low heating time, high inactivation of microorganisms, and organoleptic and nutritional properties. Furthermore, mathematical tools allow for quick and low-cost analysis of behaviors with various operating parameters. This study aimed to improve the ohmic pasteurization process of the mango pulp using computational fluid dynamics (CFD) and response surface methodology (RSM), using the experimental properties of mango pulp. The generated mathematical model is an accurate tool for predicting ohmic pasteurization behavior in an industrial environment; it presents a 4.4% standard deviation error in the experimental data. Furthermore, the arrangement and intensity of the added voltage analysis suggested operating variables with better pasteurization performance. Another observation was that the production speed was related to the voltage intensities of the inlet speed in a non-proportional manner. Additionally, operation at a low inlet velocity may be more susceptible to thermal damage, whereas operation at a high inlet velocity requires a particular proportion of voltage insertion to ensure adequate heat distribution.

Although vitamin D deficiency is a common feature among patients presenting with active tuberculosis, the full scope of vitamin D action during Mycobacterium tuberculosis (Mtb) infection is poorly understood. As macrophages are the primary site of Mtb infection and are sites of vitamin D signaling, we have used these cells to understand the molecular mechanisms underlying modulation of the immune response by the hormonal form of vitamin D, 1,25-dihydroxyvitamin D (1,25D). We found that the virulent Mtb strain H37Rv elicits a broad host transcriptional response. Transcriptome profiling also revealed that the profile of target genes regulated by 1,25D is substantially altered by infection, and that 1,25D generally boosts infection-stimulated cytokine/chemokine responses. We further focused on the role of 1,25D- and infection-induced interleukin 1β (IL-1β) expression in response to infection. 1,25D enhanced IL-1β expression via a direct transcriptional mechanism. Secretion of IL-1β from infected cells required the NLRP3/caspase-1 inflammasome. The impact of IL-1β production was investigated in a novel model wherein infected macrophages were co-cultured with primary human small airway epithelial cells. Co-culture significantly prolonged survival of infected macrophages, and 1,25D/infection-induced IL-1β secretion from macrophages reduced mycobacterial burden by stimulating the anti-mycobacterial capacity of co-cultured lung epithelial cells. These effects were independent of 1,25D-stimulated autophagy in macrophages but dependent upon epithelial IL1R1 signaling and IL-1β-driven epithelial production of the antimicrobial peptide DEFB4/HBD2. These data provide evidence that the anti-microbial actions of vitamin D extend beyond the macrophage by modulating paracrine signaling, reinforcing its role in innate immune regulation in humans.

Purpose: The implementation and certification of Management Systems International Standards, such as ISO 9001 and ISO 14001, achieved a high international recognition, with more than 1 million organizations with their Quality Management Systems certified worldwide. Researchers have been paying considerable attention to this theme and the number of published articles has robustly growth. Although, on an overall basis, the research results support the existence of positive impacts on the use and certification of these International Standards, there are various inconsistency and contradictory results, leading to some controversy over its impacts for organizations. This study aims to bring a longitudinal time perspective to this area of research, analyzing the articles published since 1996, on the benefits of Management Systems Certification. A longitudinal perspective of countries of authors origin, keywords and journals is presented, complemented with an evaluation of the research results. Design/methodology/approach: The research was supported with a Bibliometric Study, with data collected from Web of Science, SCOPUS, and Research Gate data bases. Following the detailed analysis of the journal titles, articles abstracts and their full content, an evaluation scale was applied to access if the results support the existence of a positive relationship between MSC and economic, financial or stakeholder results. Findings: The results evidence a steep increase in the number of publications addressing Management Systems Certification benefits, that mainly originate from Europe (48%) and East Asia and Pacific (23%), with Spain as the clear leading country accounting (43% of the total number of articles published between 1996 and April 2017). Journal of Cleaner Production (EMSC) and Total Quality Management and Business Excellence journal (QMSC) are the leading journals for disseminating the research and the most used keywords are “Quality/Environment”, “ISO 9001/14001”, “Performance”, “Management Systems” and “Certification”. There are also insights that the research is now open to other Management Systems either than Quality and Environment. The systematic review of the selected papers shows that the Management Systems adoption and certification brings fairly positives benefits (average 2,34 in a 1 to 5 Likert type scale) for the certified organizations, although some variations are observed. Some avenues for future research should consider the reliability and validation of measures; sampling and biases errors; the use of control, moderating and mediating variables; the consideration of time and situational contingencies; and the search for explanations for cause and effect relationships. The results of this research support the view that the investigation of Management Systems Certification benefits is indeed an issue of high academic and practitioners interest. This research, although subject to some subjective evaluation of the authors, and acknowledging that the research articles are not always comparable, aims to give some insights for this continuous research field. Research limitations/implications: Although the authors took measures to reduce subjectivity, it should be noted that the evaluation could be subject to the authors own interpretation and the research articles are not always comparable. Originality/value: This research makes a longitudinal and comprehensive evaluation of the articles published since 1996 on the benefits of Management System Certification. It highlights trends and gives contribution for future research, on a field of intense academic and practitioners interest.

Esta revisión presenta una perspectiva sobre la evolución de la esterilización térmica de alimentos líquidos enlatados y la importancia que la modelación matemática y el análisis numérico computacional han tenido en la estimación del tiempo de esterilización equivalente.

Los espacios periurbanos del área metropolitana de Santiago son el escenario de importantes transformaciones sociales, demográficas y territoriales, que se manifiestan en nuevas modalidades de ocupación del territorio rural. En este proceso de expansión de la metrópoli la función residencial es el principal motor de cambio. Tanto las viviendas en parcelas de agrado, individuales o agrupadas en condominio, como las soluciones habitacionales de carácter social, impulsadas por el Estado, contribuyen a dibujar la forma en que los asentamientos humanos se establecen en el territorio. A partir del estudio de las comunas de Pirque, Calera de Tango, Padre Hurtado y Lampa, se efectúa una lectura del nuevo diseño socio espacial que generan dichas agrupaciones residenciales.

A perspective on the evolution of liquid-food thermal sterilization and the importance of mathematical modeling and the role of computational numerical analysis in the estimation of equivalent sterilization time is presented in this work.

The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39) represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.