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The Soi crater region (0° to 60°N, 180°W to −110°W), which includes the well-preserved Soi crater in its center, spans a region from Titan's aeolian-dominated equatorial regions to fluvially-dominated high northern latitudes. This provides a rich diversity of landscapes, one that is also representative of the diversity encountered across Titan. Schoenfeld et al. (2023) mapped this region at 1:800,000 scale and produced a geomorphological map showing that the area consists of 22 types of geomorphological units. The Visual and Infrared Mapping Spectrometer (VIMS) coverage of the region enabled the detailed analysis of spectra of 261 different locations using a radiative transfer technique and a mixing model, yielding compositional constraints on Titan's optical surface layer. Additional constraints on composition on the near-surface substrate were obtained from microwave emissivity. We have derived combinations of top surface materials between dark materials, tholins, water-ice, and methane suggesting that dark mobile organic material at equatorial and high latitudes indicates “young” terrains and compositions, while tholin/water-ice mixtures that dominate areas around latitude 35°N show a material that is older plains deposits that we interpret to be the end stage of aeolian and fluvial transport and deposition. We found no spectral evidence of CO2, HC3N, and NH3 ice. We use the stratigraphic relations between the various mapping units and the relation between the geomorphology and the composition of the surface layers to build hypotheses on the origin and evolution of the regional geology. We suggest that sedimentary deposits, likely aeolian, are dominant in the region with fluvial activity and leaching changing the nature of the top surfaces of the midlatitude areas of the Soi crater region., QC 20240827

Low- and middle-income countries (LMICs) remain drastically underrepresented in health research, with African countries producing less than 1% of the global output. This work investigates authorship patterns of publications on burns in LMICs. Original research studies addressing burn injuries in LMICs and published between 1st January 2015 and 31st December 2020 were included in the review. Descriptive statistics were performed for country affiliations of authors, World Bank Country Income Groups, WHO group, study-focus and country studied. Of the 458 results, 426 studies met the inclusion criteria. Nearly a quarter of papers on burns in LMICs had both first and senior authors from high-income countries (HICs, n = 95, 24.4%), more than half of the papers had both first and senior authors from upper middle- income countries (upper MICs, n = 222, 57.2%), while less than 1% (n = 3) had first and senior authors exclusively from lower-income countries (LICs). Eleven percent (n = 41/388) of all papers were written without either first nor senior author being from the country studied, and 17 of them (41%) had both first and senior authors from the USA. Twenty-five (6%) of the papers had the first author and not the senior author from the country of focus, while six (2%) had the senior and not the first author from the country of interest. To overcome global health challenges such as burns, locally led research is imperative. The maximum benefit of HIC-LMIC collaborations is achieved when LMICs play an active role in leading the research. When LMICs direct the research being conducted in their country, the harm of inherently inequitable relationships is minimized.

Titan was a mostly unknown world prior to the Cassini spacecraft’s arrival in July 2004. We review the major scientific advances made by Cassini’s Titan Radar Mapper (RADAR) during 13 years of Cassini’s exploration of Saturn and its moons. RADAR measurements revealed Titan’s surface geology, observed lakes and seas of mostly liquid methane in the polar regions, measured the depth of several lakes and seas, detected temporal changes on its surface, and provided key evidence that Titan contains an interior ocean. As a result of the Cassini mission, Titan has gone from an uncharted world to one that exhibits a variety of Earth-like geologic processes and surface-atmosphere interactions. Titan has also joined the ranks of “ocean worlds” along with Enceladus and Europa, which are prime targets for astrobiological research.

Some of Titan's small northern hemisphere lakes show raised rampart features (which are distinct from raised rims), and appear as SAR-bright mound-like annuli extending away from the lake for up to tens of kilometers from the shoreline. We investigate the infrared and microwave characteristics of these features using Cassini Visual and Infrared Mapping Spectrometer (VIMS) and RADAR data. A spectral comparative analysis is performed among the lakes, their ramparts, and the surrounding regions. We overcome the profound difference in spatial resolution between VIMS and SAR data by using a method that provides overlays between the spectral images and SAR, thus enabling the correct selection of VIMS pixels. The surface properties of the selected areas are obtained using a radiative transfer analysis on the selected VIMS pixels, in addition to emissivity obtained from the RADAR in radiometry mode. Analysis of these combined and co-registered data provides constraints for the formation mechanism(s) of raised ramparts. The results show that the emissivity of the raised ramparts is close to that of Titan's labyrinthic terrains and to that of empty lake floors in the northern polar regions. This is confirmed by the VIMS analysis that also shows that the infrared spectral response of the raised ramparts is very similar to that of some empty lake floors. This suggests that both areas are made from or are covered by a similar material. In addition, two out of the eight lakes with raised ramparts show spectral differences at three specific wavelengths, 1.6, 2.0, and 5.0 mu m, between the ramparts and the surrounding terrain. We hypothesize that this could be due to some component, or mixture of components in the ramparts that is less absorbent at these specific wavelengths, or it could be an effect of different grain sizes. These observations provide first insights into the possible mechanisms leading to the formation of the raised ramparts that are discussed here., QC 20200713

The electron linear accelerators driving modern X-ray free-electron lasers can emit intense, tunable, quasi-monochromatic terahertz (THz) transients with peak electric fields of V Ångstrom(-1) and peak magnetic fields in excess of 10 T when a purpose-built, compact, superconducting THz undulator is implemented. New research avenues such as X-ray movies of THz-driven mode-selective chemistry come into reach by making dual use of the ultra-short GeV electron bunches, possible by a rather minor extension of the infrastructure.

Item does not contain fulltext, Sialic acid sugar-carrying glycans, sialoglycans, are aberrantly expressed on many tumor cells and have emerged as potent regulatory molecules involved in creating a tumor-supportive microenvironment. Sialoglycans can be recognized by sialic acid-binding immunoglobulin-like lectins (Siglecs), a family of immunomodulatory receptors. Most mammalian Siglecs transmit inhibitory signals comparable with the immune checkpoint inhibitor programmed death protein 1 (PD-1), but some are activating. Recent studies have shown that tumor cells can exploit sialoglycan-Siglec interactions to modulate immune cell function, contributing to an immunosuppressive tumor microenvironment (TME). Interference with sialoglycan synthesis or sialoglycan-Siglec interactions might improve antitumor immunity. Many questions regarding specificity, signaling, and regulatory function of sialoglycan-Siglec interactions remain. We posit that sialoglycans and Siglecs present as potential glyco-immune 'checkpoints' for cancer immunotherapy.

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Contains fulltext : 207003.pdf (publisher's version ) (Open Access), Cancer immunotherapy has greatly advanced in recent years. Most immunotherapeutic strategies are based on the use of immune checkpoint blockade to unleash antitumor immune responses or on the induction or adoptive transfer of immune effector cells. We aim to develop therapeutic vaccines based on recombinant Semliki Forest virus vectors to induce tumor-specific effector immune cells. In this review, we describe our ongoing work on SFV-based vaccines targeted against human papillomavirus- and hepatitis C virus-related infections and malignancies, focusing on design, delivery, combination strategies, preclinical efficacy and product development for a first-in-man clinical trial with an HPV-specific vaccine.