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The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere, which—given methane’s lifetime of several centuries—predicts an even, well mixed distribution of methane. Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.

The NOMAD (“Nadir and Occultation for MArs Discovery”) spectrometer suite on board the ExoMars Trace Gas Orbiter (TGO) has been designed to investigate the composition of Mars’ atmosphere, with a particular focus on trace gases, clouds and dust. The detection sensitivity for trace gases is considerably improved compared to previous Mars missions, compliant with the science objectives of the TGO mission. This will allow for a major leap in our knowledge and understanding of the Martian atmospheric composition and the related physical and chemical processes. The instrument is a combination of three spectrometers, covering a spectral range from the UV to the mid-IR, and can perform solar occultation, nadir and limb observations. In this paper, we present the science objectives of the instrument and explain the technical principles of the three spectrometers. We also discuss the expected performance of the instrument in terms of spatial and temporal coverage and detection sensitivity.

The surname of author Cathy Quantin-Nataf was misspelled ‘Quantin-Nata’, authors Ehouarn Millour and Roland Young were missing from the ACS and NOMAD Science Teams list, and minor changes have been made to the author and affiliation lists; see accompanying Amendment. These errors have been corrected online. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.

The surname of author Cathy Quantin-Nataf was misspelled ‘Quantin-Nata’, authors Ehouarn Millour and Roland Young were missing from the ACS and NOMAD Science Teams list, and minor changes have been made to the author and affiliation lists; see accompanying Amendment. These errors have been corrected online.

Ipilimumab (IPI) blocks CTLA-4 immune checkpoint resulting in T cell activation and enhanced antitumor immunity. IPI improves overall survival (OS) in 22% of patients with metastatic melanoma (MM). We investigated the association of CTLA-4 single nucleotide variants (SNVs) with best overall response (BOR) to IPI and OS in a cohort of 173 MM patients. Patients were genotyped for six CTLA-4 SNVs (-1661A>G, -1577G>A, -658C>T, -319C>T, +49A>G, and CT60G>A). We assessed the association between SNVs and BOR through multinomial logistic regression (MLR) and the prognostic effect of SNVs on OS through Kaplan-Meier method. Both -1577G>A and CT60G>A SNVs were found significantly associated with BOR. In particular, the proportion of responders was higher in G/G genotype while that of stable patients was higher in A/A genotype. The frequency of patients experiencing progression was similar in all genotypes. MLR evidenced a strong downward trend in the probability of responsiveness/progression, in comparison to disease stability, as a function of the allele A \"dose\" (0, 1, or 2) in both SNVs with reductions of about 70% (G/A vs G/G) and about 95% (A/A vs G/G). Moreover, -1577G/G and CT60G/G genotypes were associated with long-term OS, the surviving patients being at 3 years 29.8 and 30.8%, respectively, as compared to 12.9 and 14.4% of surviving patients carrying -1577G/A and CT60G/A, respectively. MM patients carrying -1577G/G or CT60G/G genotypes may benefit from IPI treatment in terms of BOR and long-term OS. These CTLA-4 SNVs may serve as potential biomarkers predictive of favorable outcome in this subset of patients.

Natalidad, longevidad, tecnología, inmigración, Fuerzas Armadas Abstract: In a quick look at the world, one can see a clear decreasing trend in the birth rate of the human population, while longevity is increasing. Not far from this reality is the human resource of the Armed Forces. According to trend behavior, there will be availability of human resources to cover the needs of the Armed Forces. Keywords: Natality, longevity, technology, immigration, Armed Forces 1.

In general, tourist destinations are presented as social and economic instances that try to promote individual and/or collective interest in enjoying the benefits and services that the tourism sector promotes. To do this, using a historical-comparative method, data will be collected from tourist sites in Mexico, Colombia and Chile. (Tabla i) Del mismo modo, se pueden identificar sitios por las cuales el turismo se manifiesta con mayor grado de interés. Por otra parte, unas investigaciones (González, 2016) quienes abordan la gestión de riesgos en el turismo mexicano y Latinoamericano reconocen la inseguridad como factor limitativo para la gestión estratégica de la sustentabilidad del sector turístico.

[This corrects the article on p. 386 in vol. 8, PMID: 28446908.].

Palabras-clave: 5G; sociedad digital; desarrollo; seguridad; soberanía. 5G as a vector of national sovereignty: opportunities and challenges Abstract: This research aims to measure the impact that the 5G technology to which Chile aspires in the short term will offer. The penetration of this technological platform will constitute a potential agent of change that will cover dissimilar dimensions such as education, economy, health and, without a doubt, that reaches National Security. [...]climate change; technological development; and, cybersecurity, are positioned as relevant factors in the 5G - development - security equation, the result of which will enhance national sovereignty Keywords: 5G; digital society; developing; security; sovereignty 1. En este nuevo paradigma, la sociedad digitalizada ha llevado a una dimensión antes insospechada, el manejo de la información, marcada por el surgimiento del internet, el big data e innumerables innovaciones como la inteligencia artificial, la robótica, el internet de las cosas, la nanotecnología, la web semántica, entre otras que se relacionan y se desarrollan en todas las esferas de la vida social, transformando la manera de entender la economía, la educación, la salud, la cultura, en otras palabras, el quehacer del ser humano (Palomo, 2020).

The COVID-19 pandemic has severely hampered the functioning of any health system, absorbing a considerable amount of resources and with the threat of widespread infection in the health services. The present survey has been carried out in Italy to evaluate if and how COVID-19 also affected skin melanoma management. We enrolled 13 Italian centres highly qualified in the diagnosis and care of skin melanoma. We compared a set of information evaluating the amount of activity for melanoma performed during February-April 2020 with the same quarter in 2019. The number of new melanoma diagnosis, biopsies, wide local excisions, overall pathology reports decreased. However, the most severe cases seem promptly managed with sentinel lymph node biopsies, new systemic treatments (north) and the total number of (advanced) treated patients (centre-south). The COVID-19 experience has underlined the need to exploit the help which may come from telemedicine.