Environmental costs of residuals: a characterization of efficient tax policies.

Durable goods leave residuals after being retired from use. If the environmental costs of the residuals are external to consumers and producers of the good, then overproduction and excess residuals will result. Ad valorem taxes are show to be ineffective in eliminating this externality. The efficient regulatory policy is shown to be based on a pigouvian tax.Externalities; Pollution control; Optimal taxation; Durable goods; Residuals;

Environmental costs of residuals: a characterization of efficient tax policies

Durable goods leave residuals after being retired from use. If the environmental costs of the residuals are external to consumers and producers of the good, then overproduction and excess residuals will result. Ad valorem taxes are show to be ineffective in eliminating this externality. The efficient regulatory policy is shown to be based on a pigouvian tax

Improve teaching-learning processes for computer systems engineering of the courses in distance education in TecNM

In the Technological National of Mexico in San Luis Potosí (TecNM of SLP), Studies in computer systems in Engineering are taught, with a distance education model. However, it is detected that sometimes some classes are lost, which implies little effectiveness of the model. In the present study, a collection of data on connection effectiveness was carried out, to propose a reinforcement in the courses taught. Teachers were surveyed between January 2018 and December 2018, for each session and the results showed that 96.42% of the sessions were connected and were of good quality. Even so, it was proposed the realization and use of virtual courses to which the students could have asynchronous and timeless access, as an extra support, in case the students do not attend the campuses, they want to return to the class to clarify any doubt or review the class for preparation of practical work or evaluation

Geopolíticas de la pandemia: la salud pública en perspectiva histórica

En aquesta ocasió, la secció de diàleg s’ha organitzat entre dos especialistes: Esteban Ro- dríguez Ocaña, catedràtic d’Història de la Medicina i Col·laborador extraordinari del Depar- tament d’Anatomia Patològica i Història de la Ciència de la Universitat de Granada i Joan Benach, Catedràtic del Departament de Ciències Polítiques i Socials de la Universitat Pompeu Fabra. La proposta es mantenir una conversa que consisteix a abordar de manera analítica la salut pública des d’una perspectiva històrica i alhora com una qüestió central en clau de present i futur de la societat actual. Als dos reconeguts especialistes se’ls demana que aportin les seves reflexions sobre aquest as- sumpte des de camps disciplinaris diferents, amb l’objectiu principal d’oferir a les historiadors i historiadores instruments teòrics i metodològics amb què abordar els problemes i els models que ha plantejat i planteja la noció de “salut pública”. En els moments actuals ens sembla que aquest exercici contribueix a enfortir algunes de les línies de recerca ja existents i estimular noves línies amb què pensar el present en clau històrica. Finalment, ens sembla que val la pena esmentar que l’enregistrament d’aquest diàleg, poste- riorment transcrit per Andrea Tappi i revisat tant pels autors com per nosaltres com a editors, ha estat utilitzat com una activitat per als alumnes de l’assignatura “Pensar la Història Escoles, Teories i Interpretacions” de Primer Curs de Grau impartit a la Secció d’Història Contem- porània i Món Actual del Departament d’Història i Arqueologia de la Universitat de Barcelona. Els resultats obtinguts en aquesta pràctica, amb els informes lliurats del seu seguiment, i la resposta molt positiva que ofereix l’alumnat seria molt probablement matèria d’un altre diàleg futur sobre l’ensenyament universitari de la Història.On this occasion, the dialogue section has been organized between two specialists: Esteban Rodríguez Ocaña, Professor of History of Medicine and Special Collaborator of the Depart- ment of Pathological Anatomy and History of Science of the University of Granada, and Joan Benach, Professor of the Department of Political and Social Sciences of the Pompeu Fabra University. It is a proposal for a dialogue that consists of analytically approaching public health from a historical perspective and, at the same time, as a central issue in terms of the present and future of today’s society. The two renowned specialists were asked to contribute their reflections on this matter from different disciplinary fields, with the main objective of offering historians theoretical and methodological instruments with which to address the problems and models posed by the notion of “public health”. At present, it seems to us that this exercise contributed to the strengthening of some of the already existing research lines, and to stimulating new lines with which to think about present time in a historical key. Finally, we think it is worth mentioning that the recording of this dialogue, later transcribed by Andrea Tappi and reviewed both by the authors and by us as editors, has been used as an activity for the students of the subject “Thinking History. Schools, Theories and Interpreta- tions” of the First Degree Course, taught in the Contemporary History and Current World Section of the Department of History and Archaeology of the University of Barcelona.The results obtained in this activity, with the reports delivered on its follow-up, as well as the very positive response of the students, would most likely be the subject of another future dialogue, focused on university teaching of History.En esta ocasión la sección de diálogo se ha organizado entre dos especialistas: Esteban Ro- dríguez Ocaña, catedrático de Historia de la Medicina y Colaborador extraordinario del De- partamento de Anatomía Patológica e Historia de la Ciencia de la Universidad de Granada y Joan Benach, catedrático del Departamento de Ciencias Políticas y Sociales de la Universidad Pompeu Fabra. La propuesta es una conversación que consiste en abordar de manera analítica la salud pú- blica desde una perspectiva histórica y, al mismo tiempo, como una cuestión central en clave de presente y futuro de la sociedad actual. A los dos reconocidos especialistas se les pide que aporten sus reflexiones sobre este asunto desde campos disciplinarios diferentes, con el objetivo principal de ofrecer a los historiadores y las historiadoras instrumentos teóricos y metodológicos con los que abordar los problemas y los modelos que ha planteado y plantea la noción de “salud pública”. En los momentos actuales nos parece que este ejercicio contribuye a fortalecer algunas de las líneas de investigación ya existentes y estimular nuevas líneas con las que pensar el presente en clave histórica. Por último, nos parece que vale la pena mencionar que la grabación de este diálogo, pos- teriormente transcrito por Andrea Tappi y revisado tanto por los autores como por nosotros como editores, ha sido utilizado como una actividad para los alumnos de la asignatura “Pensar la Historia Escuelas,Teorías e Interpretaciones” del Grupo B1 del Primer Curso de Grado, impartido en la Sección de Historia Contemporánea y Mundo Actual del Departamento de Historia y Arqueología de la Universidad de Barcelona. Los resultados obtenidos en esta práctica, con los informes entregados de su seguimiento, y la respuesta muy positiva ofrecida por el alumnado sería muy probablemente materia de otro diálogo futuro sobre la enseñanza universitaria de la Historia

High TGFβ-Smad Activity Confers Poor Prognosis in Glioma Patients and Promotes Cell Proliferation Depending on the Methylation of the PDGF-B Gene

SummaryTGFβ acts as a tumor suppressor in normal epithelial cells and early-stage tumors and becomes an oncogenic factor in advanced tumors. The molecular mechanisms involved in the malignant function of TGFβ are not fully elucidated. We demonstrate that high TGFβ-Smad activity is present in aggressive, highly proliferative gliomas and confers poor prognosis in patients with glioma. We discern the mechanisms and molecular determinants of the TGFβ oncogenic response with a transcriptomic approach and by analyzing primary cultured patient-derived gliomas and human glioma biopsies. The TGFβ-Smad pathway promotes proliferation through the induction of PDGF-B in gliomas with an unmethylated PDGF-B gene. The epigenetic regulation of the PDGF-B gene dictates whether TGFβ acts as an oncogenic factor inducing PDGF-B and proliferation in human glioma

De Novo Lipogenesis in Adipose Tissue Is Associated with Course of Morbid Obesity after Bariatric Surgery

OBJECTIVE: De novo lipogenesis is involved in fatty acid biosynthesis and could be involved in the regulation of the triglyceride storage capacity of adipose tissue. However, the association between lipogenic and lipolytic genes and the evolution of morbidly obese subjects after bariatric surgery remains unknown. In this prospective study we analyze the association between the improvement in the morbidly obese patients as a result of bariatric surgery and the basal expression of lipogenic and lipolytic genes. METHODS: We study 23 non diabetic morbidly obese patients who were studied before and 7 months after bariatric surgery. Also, we analyze the relative basal mRNA expression levels of lipogenic and lipolytic genes in epiploic visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (SAT). RESULTS: When the basal acetyl-CoA carboxylase 1 (ACC1), acetyl-CoA synthetase 2 (ACSS2) and ATP citrate lyase (ACL) expression in SAT was below percentile-50, there was a greater decrease in weight (P = 0.006, P = 0.034, P = 0.026), body mass index (P = 0.008, P = 0.033, P = 0.034) and hip circumference (P = 0.033, P = 0.021, P = 0.083) after bariatric surgery. In VAT, when the basal ACSS2 expression was below percentile-50, there was a greater decrease in hip circumference (P = 0.006). After adjusting for confounding variables in logistic regression models, only the morbidly obese patients with SAT or VAT ACSS2 expression ≥ P50 before bariatric surgery had a lower percentage hip circumference loss (<P50) after bariatric surgery (SAT: P = 0.039; VAT: P = 0.033). CONCLUSIONS: A lower basal ACSS2, ACC1 and ACL expression, genes involved in de novo lipogenesis, is associated with a better evolution of anthropometric variables after bariatric surgery. Thus, the previous state of the pathways involved in fatty acid metabolism may have repercussions on the improvement of these patients

Clinical, Molecular and Genetic Characteristics of Early Onset Gastric Cancer: Analysis of a Large Multicenter Study

Gastric adenocarcinoma (GC) is a common tumor with high morbidity and mortality. Only 7% of patients with GC are diagnosed before age 50 (early onset gastric cancer (EOGC)), and their characteristics have been poorly described. We aimed to describe clinical, molecular, and genetic characteristics of EOGC. A total of 309 patients with EOGC were retrospectively studied in four Spanish centers. Personal information, family history, and tumor information were registered. Germinal genetic analysis was performed in patients who met current criteria of a hereditary syndrome at the time of diagnosis. The median age at diagnosis was 44 years. The majority (73.3%) of tumors were diffuse, and 78.3% were diagnosed in an advanced stage. Familial aggregation of GC was present in 18/117 (15.4%) cases, and 5/117 (4.3%) met criteria for familial GC. MMR-IHC was performed in 126/309 (40.7%) tumors: 4/126 (3.1%) had loss of expression in MLH1/PMS2, without an associated germline mutation. Sixteen germline genetic analyses were performed, detecting a pathogenic variant in four (25%) cases: one in BRCA2, one in TP53, and two in CDH1. Most EOGC are diffuse and diagnosed in an advanced stage. In these patients, DNA MMR system deficiency is uncommon. Although familial aggregation was observed in only 15% of cases, a germline mutation was found in 25% of patients tested with clinical criteria. This demonstrates that EOGC has a marked genetic heterogeneity, reinforcing the importance of an accurate genetic counseling and enhancing the emerging use of multigene panels

The 2011 October Draconids outburst. I. Orbital elements, meteoroid fluxes and 21P/Giacobini-Zinner delivered mass to Earth

On October 8th, 2011 the Earth crossed the dust trails left by comet 21P/Giacobini-Zinner during its XIX and XX century perihelion approaches with the comet being close to perihelion. The geometric circumstances of that encounter were thus favorable to produce a meteor storm, but the trails were much older than in the 1933 and 1946 historical encounters. As a consequence the 2011 October Draconid display exhibited several activity peaks with Zenithal Hourly Rates of about 400 meteors per hour. In fact, if the display had been not forecasted, it could have passed almost unnoticed as was strongly attenuated for visual observers due to the Moon. This suggests that most meteor storms of a similar nature could have passed historically unnoticed under unfavorable weather and Moon observing conditions. The possibility of obtaining information on the physical properties of cometary meteoroids penetrating the atmosphere under low-geocentric velocity encounter circumstances motivated us to set up a special observing campaign. Added to the Spanish Fireball Network wide-field all-sky and CCD video monitoring, other high-sensitivity 1/2" black and white CCD video cameras were attached to modified medium-field lenses for obtaining high resolution orbital information. The trajectory, radiant, and orbital data of 16 October Draconid meteors observed at multiple stations are presented. The results show that the meteors appeared from a geocentric radiant located at R.A.=263.0+-0.4 deg. and Dec.=+55.3+-0.3 deg. that is in close agreement with the radiant predicted for the 1873-1894 and the 1900 dust trails. The estimated mass of material from 21P/Giacobini-Zinner delivered to Earth during the six-hours outburst was around 950+-150 kg.Comment: Manuscript in press in Monthly Notices of the Royal Astronomical Society, submitted to MNRAS on November 16th, 2012 Accepted for publication in MNRAS on April 28th, 2013 Manuscript Pages: 21 Tables: 8 Figures: 4 Manuscript associated: "The 2011 October Draconids outburst. II. Meteoroid chemical abundances from fireball spectroscopy" by J.M. Madiedo is also in press in the same journa

The 2011 October Draconids outburst-I. Orbital elements, meteoroid fluxes and 21P/Giacobini-Zinner delivered mass to Earth

On 2011 October 8, the Earth crossed the dust trails left by comet 21P/Giacobini-Zinner during its 19th and 20th century perihelion approaches with the comet being close to perihelion. The geometric circumstances of that encounter were thus favourable to produce a meteor storm, but the trails were much older than in the 1933 and 1946 historical encounters. As a consequence the 2011 October Draconid display exhibited several activity peaks with Zenithal Hourly Rates of about 400 meteors h-1. In fact, if the display had not been forecasted, it could have passed almost unnoticed as was strongly attenuated for visual observers due to the Moon. This suggests that most meteor storms of a similar nature could have passed historically unnoticed under unfavourable weather and Moon observing conditions. The possibility of obtaining information on the physical properties of cometary meteoroids penetrating the atmosphere under low geocentric velocity encounter circumstances motivated us to set up a special observing campaign. Added to the Spanish Fireball Network wide-field all-sky and CCD video monitoring, other high-sensitivity 1/2 arcsec black and white CCD videocameras were attached to the modified medium-field lenses for obtaining high-resolution orbital information. The trajectory, radiant and orbital data of October 16 Draconid meteors observed at multiple stations are presented. The results show that the meteors appeared from a geocentric radiant located at α = 263.0 ± 0°.4 and δ =+55.3 ± 0°.3 that is in close agreement with the radiant predicted for the 1873-1894 and the 1900 dust trails. The estimated mass of material from 21P/Giacobini-Zinner delivered to Earth during the 6 h outburst was around950 ±150 kg