5 research outputs found
Molecular Design and Spodumene Flotation—A Review
Spodumene flotation stands as the most commonly used method to concentrate lithium minerals. However, it faces significant challenges related to low collector recoveries and similarity in the surface characteristics of the minerals, which make the effective separation of this valuable mineral difficult. For this reason, numerous researchers have conducted studies to address and confront this problem. In this work, an exhaustive bibliographic search was carried out using keywords and search queries, and the results were structured in three sections according to temporal, methodological, and thematic criteria. The first section covers the period from 1950 to 2004, focusing on experimental tests. The second section covers from 2004 to the present and focuses on flotation tests and measurement analysis. Simultaneously, the third section spans from 2011 to the present and is based on molecular dynamics simulations. Topics covered include spodumene surface properties, the influence of metal ions, pre-treatment techniques, and the use of collectors. Ultimately, molecular dynamics simulations are positioned as a tool that accurately represents experimental phenomena. In this context, specialized software such as Materials Studio or Gromacs prove to be reliable instruments that allow a detailed study of mineral surfaces and other elements to be carried out, which justifies their consideration for future research in this scientific field
Surface Morphology of Vapor-Deposited Chitosan: Evidence of Solid-State Dewetting during the Formation of Biopolymer Films
Chitosan
is a useful and versatile biopolymer with several industrial
and biological applications. Whereas its physical and physicochemical
bulk properties have been explored quite intensively in the past,
there is a lack of studies regarding the morphology and growth mechanisms
of thin films of this biopolymer. Of particular interest for applications
in bionanotechnology are ultrathin films with thicknesses under 500
Ă…. Here, we present a study of thin chitosan films prepared in
a dry process using physical vapor deposition and <i>in situ</i> ellipsometric monitoring. The prepared films were analyzed with
atomic force microscopy in order to correlate surface morphology with
evaporation parameters. We find that the surface morphology of our
final thin films depends on both the optical thickness, i.e., measured
with ellipsometry, and the deposition rate. Our work shows that ultrathin
biopolymer films can undergo dewetting during film formation, even
in the absence of solvents and thermal annealing
Chilean Gastric Cancer Task Force: a study protocol to obtain a clinical and molecular classification of a cohort of gastric cancer patients
Gastric cancer (GC) is the world’s second-leading cause of neoplastic mortality. Genetic alterations, response to treatments, and mortality rates are highly heterogeneous across different regions. Within Latin America, GC is the leading cause of cancer death in Chile, affecting 17.6 per 100,000 people and causing >3000 deaths/y. Clinical outcomes and response to “one size fits all” therapies are highly heterogeneous and thus a better stratification of patients may aid cancer treatment and response. The Gastric Cancer Task Force is a Chilean collaborative, noninterventional study that seeks to stratify gastric adenocarcinomas using clinical outcomes and genomic, epigenomic, and protein alterations in a cohort of 200 patients. Tumor samples from the Pathology Department and the Cancer Center at UC-Christus healthcare network, Pontificia Universidad Católica de Chile will be analyzed using a panel of 143 known cancer genes (Oncomine Comprehensive Assay) at the Center of Excellence in Precision Medicine in Santiago, Chile. In addition, promoter methylation for selected genes will be performed along with tissue microarray for clinically relevant proteins (e.g., PD-L1, Erb-2, VEGFR2, among others) and Helicobacter pylori and Epstein–Barr virus status. Obtained data will be correlated to 120 clinical parameters retrieve from medical records, including general patient information, cancer history, laboratory studies, comorbidity index, chemotherapy, targeted therapies, efficacy, and follow-up. The development of a clinically meaningful classification that encompasses comprehensive clinical and molecular parameters may improve patient treatment, predict clinical outcomes, aid patient selection/stratification for clinical trials and may offer insights into future preventive and/or therapeutic strategies in patients from Latin America region. Trial registration: ClinicalTrials.gov Identifier: NCT03158571, Registered on May 18, 2017