Termodinámica - Notas de clase

Estos apuntes son una recopilación de notas de clase de la asignatura de Termodinámica; incluyen además en cada tema algunos problemas resueltos, bastantes de exámenes anteriores. La función de estas notas es servir de apoyo al estudio de la asignatura, pero en ningún caso pretenden sustituir el uso de libros de texto. Son fruto de varios años de docencia de esta asignatura en la Escuela de Ingenieros de San Sebastián, de la Universidad de Navarra

A Small Non-Coding RNA Modulates Expression of Pilus-1 Type in Streptococcus pneumoniae

Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, and about 30% of the pneumococcal clinical isolates show type I pili-like structures. These long proteinaceous polymers extending from the bacterial surface are encoded by pilus islet 1 and play major roles in adhesion and host colonization. Pili expression is bistable and is controlled by the transcriptional activator RlrA. In this work, we demonstrate that the previously identified small noncoding RNA srn135 also participates in pilus regulation. Our findings show that srn135 is generated upon processing of the 5'-UTR region of rrgA messenger and its deletion prevents the synthesis of RrgA, the main pili adhesin. Moreover, overexpression of srn135 increases the expression of all pili genes and rises the percentage of piliated bacteria within a clonal population. This regulation is mediated by the stabilization of rlrA mRNA since higher levels of srn135 increase its half-life to 165%. Our findings suggest that srn135 has a dual role in pilus expression acting both in cis- (on the RrgA levels) and in trans- (modulating the levels of RlrA) and contributes to the delicate balance between pili expressing and non-expressing bacteria.This research was funded by Fondo de Investigación Sanitaria (FIS), grant number PI11/00656, and Ministerio de Economía, Industria y Competitividad, grant number BIO2017-82951-R.” P.A. was the recipient of a contract funded by the FIS project PI11/00656 and A.G.-S. was the recipient of a contract funded by Instituto de Salud Carlos III (CA10/1103).S

Steam oxidation of ferritic steels : kinetics and microstructure

The ferritic 2.25Cr–1Mo steel has been subjected to isothermal and non-isothermal oxidation treatments in water steam at several temperatures ranging from 550 to 700 °C for up to 56 days. Under isothermal conditions this steel follows a parabolic oxidation kinetics, with an activation energy of 324 kJ mol –1 . This value corresponds to an apparent activation energy for the global process, which includes both outward diffusion of Fe cations and inward diffusion of oxygen. The oxidation products present in the oxide scales, which were characterised by X-ray diffraction and SEM, are in total agre - ement with the Fe-O phase diagram. Thus, magnetite is the most stable oxide at low temperatures and wustite starts to form above 570 °C. Further studies of the effect of cooling rate have shown that wustite formed at 700 °C transforms into magne - tite during a slow cooling, whereas a rapid cooling inhibits this transformation to a certain extent. For non-isothermal oxidation treatments consisting of a holding period at 550 °C followed by a single or double 4 hours exposure at 700 °C, the oxidation process seems to occur in sequence, thus presenting an additive effect of the oxidation treatments carried out at each temperature. This effect was observed both, for the type of oxide grown, and for the kinetics of the process. Microscopic observations of the oxide scales formed after the various oxidation treatments revealed that the oxide scales are constituted by sublayers of distinct microstructure and chemical composition changing from their surface to the substrate interface

Comparative analysis of heat dissipation panels for a hybrid cooling system integrated in buildings

The use of cooling panels as heat dissipation elements integrated in buildings has been previously investigated by the authors. Those elements would be connected to the condenser and would dissipate the heat in a passive form. Following the research, this study analyses and compares the thermal performance of two heat dissipation panels as part of a hybrid cooling system. Both panels were experimentally tested under different variables, thus having nine scenarios for each panel. Additionally, an already validated model was applied. The empirical results show a considerable difference between the cooling capacity among them, doubling the daily average ratio in one scenario. The heat dissipation ratios vary between 106 and 227 W/m2 in the first case and 140 and 413 W/m2 in the second. Regarding the model applicability, the average error for each panel was 4.0% and 8.5%. The bond between the metal sheet and the pipes of the panels has proven to be the main parameter to assure the highest heat dissipation potential of each panel

Risk of breast cancer and residential proximity to industrial installations: New findings from a multicase-control study (MCC-Spain)

Breast cancer is the most frequent tumor in women worldwide, although well-established risk factors account for 53%-55% of cases. Therefore, other risk factors, including environmental exposures, may explain the remaining variation. Our objective was to assess the relationship between risk of breast cancer and residential proximity to industries, according to categories of industrial groups and specific pollutants released, in the context of a population-based multicase-control study of incident cancer carried out in Spain (MCC-Spain). Using the current residence of cases and controls, this study was restricted to small administrative divisions, including both breast cancer cases (452) and controls (1511) in the 10 geographical areas recruiting breast cancer cases. Distances were calculated from the respective woman's residences to the 116 industries located in the study area. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance (between 1 km and 3 km) to industrial plants, adjusting for matching variables and other confounders. Excess risk (OR; 95%CI) of breast cancer was found near industries overall (1.30; 1.00-1.69 at 3 km), particularly organic chemical industry (2.12; 1.20-3.76 at 2.5 km), food/beverage sector (1.87; 1.26-2.78 at 3 km), ceramic (4.71; 1.62-13.66 at 1.5 km), surface treatment with organic solvents (2.00; 1.23-3.24 at 3 km), and surface treatment of plastic and metals (1.51; 1.06-2.14 at 3 km). By pollutants, the excess risk (OR; 95%CI) was detected near industries releasing pesticides (2.09; 1.14-3.82 at 2 km), and dichloromethane (2.09; 1.28-3.40 at 3 km). Our results suggest a possible increased risk of breast cancer in women living near specific industrial plants and support the need for more detailed exposure assessment of certain agents released by these plants.The authors thank all those who took part in this study providing questionnaire data. The study was partially funded by the “Acción Transversal del Cáncer", approved on the Spanish Ministry Council on the 11th October 2007, by the Scientific Foundation of the Spanish Association Against Cancer (Fundación Científica de la Asociación Española Contra el Cáncer (AECC) – EVP-1178/14), by the Spain's Health Research Fund (Fondo de Investigación Sanitaria - FIS 12/01416), by the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/0533, PI08/1359 PS09/01286-León, PS09/00773-Cantabria, PS09/02078-Huelva, PS09/01903-Valencia, PS09/01662-Granada, PI11/01403, PI11/01889-FEDER, PI11/00226, PI11/01810, PI11/02213, PI12/00488, PI12/00265, PI12/01270, PI12/00715, PI12/00150, PI14/01219, PI14/00613, PI15/00069, PI15/00914, PI15/01032), by the ICGC International Cancer Genome Consortium CLL (The ICGC CLL-Genome Project is funded by Spanish Ministerio de Economía y Competitividad (MINECO) through the Instituto de Salud Carlos III (ISCIII) and Red Temática de Investigación del Cáncer (RTICC) del ISCIII (RD12/0036/0036)), by the Fundación Marqués de Valdecilla (API 10/09), by the Consejería de Salud of the Junta de Andalucía (PI-0571-2009, PI-0306-2011, salud201200057018tra), by the Junta de Castilla y León (LE22A10-2), by the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10), by the Regional Government of the Basque Country, by the Recercaixa (2010ACUP 00310), by the European Commission grants FOOD-CT-2006-036224-HIWATE, by the Spanish Association Against Cancer (AECC) Scientific Foundation, by the Catalan Government DURSI grant 2017SGR723, by the University of Oviedo, and by the Fundación Caja de Ahorros de Asturias. ISGlobal is a member of the CERCA Program, Generalitat de Catalunya.S

Risk of gastric cancer in the environs of industrial facilities in the MCC-Spain study

Background: Gastric cancer is the fifth most frequent tumor worldwide. In Spain, it presents a large geographic variability in incidence, suggesting a possible role of environmental factors in its etiology. Therefore, epidemiologic research focused on environmental exposures is necessary. Objectives: To assess the association between risk of gastric cancer (by histological type and tumor site) and residential proximity to industrial installations, according to categories of industrial groups and specific pollutants released, in the context of a population-based multicase-control study of incident cancer conducted in Spain (MCC-Spain). Methods: In this study, 2664 controls and 137 gastric cancer cases from 9 provinces, frequency matched by province of residence, age, and sex were included. Distances from the individuals' residences to the 106 industries located in the study areas were computed. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance (from 1 km to 3 km) to industries, adjusting for matching variables and potential confounders. Results: Overall, no excess risk of gastric cancer was observed in people living close to the industrial installations, with ORs ranging from 0.73 (at ≤2.5 km) to 0.93 (at ≤1.5 km). However, by industrial sector, excess risks (OR; 95%CI) were found near organic chemical industry (3.51; 1.42-8.69 at ≤2 km), inorganic chemical industry (3.33; 1.12-9.85 at ≤2 km), food/beverage sector (2.48; 1.12-5.50 at ≤2 km), and surface treatment using organic solvents (3.59; 1.40-9.22 at ≤3 km). By specific pollutant, a statistically significant excess risk (OR; 95%CI) was found near (≤3 km) industries releasing nonylphenol (6.43; 2.30-17.97) and antimony (4.82; 1.94-12.01). Conclusions: The results suggest no association between risk of gastric cancer and living in the proximity to the industrial facilities as a whole. However, a few associations were detected near some industrial sectors and installations releasing specific pollutants.The authors thank all those who took part in this study by providing questionnaire data. This study was funded by: Scientific Foundation of the Spanish Association Against Cancer (Fundación Científica de la Asociación Española Contra el Cáncer (AECC) e grants EVP-1178/14 and GCTRA18022MORE); “Acción Transversal del Cáncer”, approved on the Spanish Ministry Council on October 11, 2007; Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP); Spain’s Health Research Fund (Fondo de Investigación Sanitaria - FIS 12/01416); Carlos III Institute of Health (ISCIII) grants, co-funded by ERDF fundsea way to build Europee (grants PI08/0533, PI08/1359, PI08/1770, PS09/00773, PS09/01286, PS09/01662, PS09/01903, PS09/02078, PI11/00226, PI11/01403, PI11/01810, PI11/01889, PI11/02213, PI12/00150, PI12/00265, PI12/00488, PI12/00715, PI12/01270, PI14/00613, PI14/01219, PI15/00069, PI15/00914, PI15/01032, PI17-00092, PI17CIII/00034); the Fundación Marqués de Valdecilla (API 10/09); the Junta de Castilla y León (LE22A10-2); the Consejería de Salud of the Junta de Andalucía (PI-0571-2009, PI-0306-2011, salud201200057018tra); the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10); the Recercaixa (2010ACUP 00310); the European Commission grants FOOD-CT-2006-036224-HIWATE; the Catalan Government-Agency for Management of University and Research Grants (AGAUR) grants 2017SGR723 and 2014SGR850; the Catalan Government DURSI grant 2014SGR647; the Fundación Caja de Ahorros de Asturias; and the University of Oviedo. ISGlobal acknowledges support from the Spanish Ministry of Science and Innovation through the “Centro de Excelencia Severo Ochoa 2019-2023” Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program.N

Adherence to the Western, Prudent and Mediterranean dietary patterns and breast cancer risk: MCC-Spain study

Objective To externally validate the previously identified effect on breast cancer risk of the Western, Prudent and Mediterranean dietary patterns. Study design MCC-Spain is a multicase-control study that collected epidemiological information on 1181 incident cases of female breast cancer and 1682 control cases from 10 Spanish provinces. Three dietary patterns derived in another Spanish case-control study were analysed in the MCC-Spain study. These patterns were termed Western (high intakes of fatty and sugary products and red and processed meat), Prudent (high intakes of low-fat dairy products, vegetables, fruits, whole grains and juices) and Mediterranean (high intake of fish, vegetables, legumes, boiled potatoes, fruits, olives, and vegetable oil, and a low intake of juices). Their association with breast cancer was assessed using logistic regression models with random province-specific intercepts considering an interaction with menopausal status. Risk according to tumour subtypes ? based on oestrogen (ER), progesterone (PR) and human epidermal growth factor 2 (HER2) receptors (ER+/PR+&HER2-; HER2+; ER-/PR-&HER2-) ? was evaluated with multinomial regression models. Main outcome measures Breast cancer and histological subtype. Results Our results confirm most of the associations found in the previous case-control study. A high adherence to the Western dietary pattern seems to increase breast cancer risk in both premenopausal women (OR4thvs.1stquartile(95%CI):1.68(1.02;2.79); OR1SD-increase(95%CI): 1.19(1.01;1.40)) and postmenopausal women (OR4thvs.1stquartile(95%CI):1.48(1.07;2.05); OR1SD-increase(95%CI): 1.14(1.01;1.28)). While high adherence to the Prudent pattern did not show any effect on breast cancer, the Mediterranean dietary pattern seemed to be protective, but only among postmenopausal women (OR4thvs.1stquartile (95%CI):0.72(95% CI 0.53;0.98); p-int = 0.075). There were no significant differences by tumour subtype. Conclusion Dietary recommendations based on a departure from the Western dietary pattern in favour of the Mediterranean diet could reduce breast cancer risk in the general population.The study was funded by Carlos III Institute of Health grants (PI12/00488, PI12/00265, PI12/00715, PI12/01270, PI09/00773 and PI08/1770), by the Spanish Ministry of Economy and Competitiveness (IJCI-2014-20900) and by Consejería de Salud de la Junta de Andalucía (PI-0571- 2009 and PI-0306-2011) competitive calls including peer review for scientific quality. Additional funding was provided by the Spanish Federation of Breast Cancer Patients (FECMA: EPY 1169- 10), the Association of Women with Breast Cancer from Elche (AMACMEC:EPY 1394/15), the Marqués de Valdecilla foundation (grant API 10/09), ) and by Acción Transversal del Cancer, approved by the Spanish Ministry Council on October 11, 2007. None of the funders played any role in conducting research or writing the paper

Effect of mistimed eating patterns on breast and prostate cancer risk (MCC-Spain Study)

Modern life involves mistimed sleeping and eating patterns that in experimental studies are associated with adverse health effects. We assessed whether timing of meals is associated with breast and prostate cancer risk taking into account lifestyle and chronotype, a characteristic correlating with preference for morning or evening activity. We conducted a population-based case-control study in Spain, 2008-2013. In this analysis we included 621 cases of prostate and 1,205 of breast cancer and 872 male and 1,321 female population controls who had never worked night shift. Subjects were interviewed on timing of meals, sleep and chronotype and completed a Food Frequency Questionaire. Adherence to the World Cancer Research Fund/American Institute of Cancer Research recommendations for cancer prevention was examined. Compared with subjects sleeping immediately after supper, those sleeping two or more hours after supper had a 20% reduction in cancer risk for breast and prostate cancer combined (adjusted Odds Ratio [OR] = 0.80, 95%CI 0.67-0.96) and in each cancer individually (prostate cancer OR = 0.74, 0.55-0.99; breast cancer OR = 0.84, 0.67-1.06). A similar protection was observed in subjects having supper before 9 pm compared with supper after 10 pm. The effect of longer supper-sleep interval was more pronounced among subjects adhering to cancer prevention recommendations (OR both cancers= 0.65, 0.44-0.97) and in morning types (OR both cancers = 0.66, 0.49-0.90). Adherence to diurnal eating patterns and specifically a long interval between last meal and sleep are associated with a lower cancer risk, stressing the importance of evaluating timing in studies on diet and cancer

Sleep duration and napping in relation to colorectal and gastric cancer in the MCC-Spain study

[EN] Sleep duration is a novel and potentially modifiable risk factor for cancer. We evaluated the association of self‑reported sleep duration and daytime napping with odds of colorectal and gastric cancer. We included 2008 incident colorectal cancer cases, 542 gastric cancer cases and 3622 frequency‑matched population controls, recruited in the MCC‑Spain case–control study (2008–2013). Sleep information, socio‑demographic and lifestyle characteristics were obtained through personal interviews. Multivariable adjusted logistic regression models were used to estimate odds ratios (OR) with 95% confidence intervals (CI) for cancer, across categories of sleep duration (≤ 5, 6, 7, 8, ≥ 9 hours/day), daytime napping frequency (naps/week) and duration (minutes/nap). Compared to 7 hours of sleep, long sleep was associated with increased odds of colorectal (OR ≥9 hours : 1.59; 95%CI 1.30–1.94) and gastric cancer (OR ≥9 hours : 1.95; 1.37–2.76); short sleep was associated with increased odds of gastric cancer (OR ≤5 hours : 1.32; 0.93–1.88). Frequent and long daytime naps increased the odds of colorectal (OR6–7 naps/week, ≥30 min : 1.32; 1.14–1.54) and gastric cancer (OR 6–7 naps/week, ≥30 min : 1.56; 1.21–2.02). Effects of short sleep and frequent long naps were stronger among participants with night shift‑work history. Sleep and circadian disruption may jointly play a role in the etiology of colorectal and gastric cancerS

The RS4939827 polymorphism in the SMAD7 GENE and its association with Mediterranean diet in colorectal carcinogenesis

[EN] The objective of our investigation is to study the relationship between the rs4939827 SNP in the SMAD7 gene, Mediterranean diet pattern and the risk of colorectal cancer.We examined 1087 cases of colorectal cancer and 2409 population controls with available DNA samples from the MCC-Spain study, 2008–2012. Descriptive statistical analyses, and multivariate logistic mixed models were performed. The potential synergistic effect of rs4939827 and the Mediterranean diet pattern was evaluated with logistic regression in different strata of of adherence to the Mediterranean diet and the genotype. High adherence to Mediterrenean diet was statistically significantly associated with colorectal cancer risk. A decreased risk for CRC cancer was observed for the CC compared to the TT genotype (OR = 0.65 and 95% CI = 0.51–0. 81) of the rs4939827 SNP Also, we could show an association between the Mediterranean diet pattern (protective factor) and rs4939827. Although the decreased risk for the CC genotype was slightly more pronounced in subjects with high adherence to Mediterrenean diet, there was no statistically significant synergistic effect between genotype CC and adherence to the Mediterranean dietary pattern factors. The SMAD7 gene and specifically the allele C could be protective for colorectal cancer. An independent protective association was also observed between high adherence Mediterranean diet pattern and CRC risk. Findings form this study indicate that high adherence to Mediterranean diet pattern has a protective role for CRC cancer probably involving the Tumor Growth Factor- β pathway in this cancer.S