RESUMEN
Optical materials play a key role in enabling modern optoelectronic technologies in a wide variety of domains such as the medical or the energy sector. Among them, nonlinear optical crystals are of primary importance to achieve a broader range of electromagnetic waves in the devices. However, numerous and contradicting requirements significantly limit the discovery of new potential candidates, which, in turn, hinders the technological development. In the present work, the static nonlinear susceptibility and dielectric tensor are computed via density-functional perturbation theory for a set of 579 inorganic semiconductors. The computational methodology is discussed and the provided database is described with respect to both its data distribution and its format. Several comparisons with both experimental and ab initio results from literature allow to confirm the reliability of our data. The aim of this work is to provide a relevant dataset to foster the identification of promising nonlinear optical crystals in order to motivate their subsequent experimental investigation.
RESUMEN
INTRODUCTION: Aim of this study was to analyze the overall complication and failure rates of Peripherally Inserted Central Catheters (PICCs), in a 1-year consecutive unselected cohort of 482 adult patients, affected by non-hematological malignancies undergoing chemotherapy. METHODS: Adult outpatients (aged 18-75 years), with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, bearing solid tumors and candidates for intravenous chemotherapy were eligible for the study. Exclusion criteria were active infections, coagulopathy (defined as platelet count <50,000/µL and/or prothrombin time more than 18 s), life expectancy <6 months, or inability to give written informed consent. Devices were all implanted in an outpatients' hospital facility, following predefined evidence-based institutional guidelines and protocols by a PICC-dedicated team at the European Institute of Oncology in Milan, Italy, during the 12-month period from January 1 to December 31, 2019. RESULTS: Five-hundred PICCs were implanted in a cohort of 482 patients during the time interval of this study. Thirty devices were overall removed (6.2%), 23 as a consequence of a complication occurred, and seven inadvertently. The inserted PICCs accounted for a total of 49,718 catheter days in situ, median duration was 85.5 days [interquartile range (IQR): 56-146]. Overall there were 42 (8.7%) complications, corresponding to 0.84 catheter-adverse events (CAE)/1000 PICC-days (95% CI: 0.61-1.14). There were N = 13 (2.7%) thromboses, N = 11 (2.3%) irreversible occlusions, N = 7 (1.5%) accidental removals, N = 5 (1.0%) infections [two Catheter Related Blood Stream Infection (CRBSI) and three exit site/local infection], N = 3 (0.6%) ruptures and N = 3 (0.6%) primary or secondary malpositions. CONCLUSION: This large prospective study supports the increasing use of PICCs in adult oncology outpatients treated in specialized centers with chemotherapy for non-hematological malignancies. In this clinical setting, PICC failure occurred in 6% only of the inserted devices.
Asunto(s)
Infecciones Relacionadas con Catéteres , Cateterismo Venoso Central , Cateterismo Periférico , Catéteres Venosos Centrales , Neoplasias , Adulto , Infecciones Relacionadas con Catéteres/diagnóstico , Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Catéteres Venosos Centrales/efectos adversos , Humanos , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
abinit is probably the first electronic-structure package to have been released under an open-source license about 20 years ago. It implements density functional theory, density-functional perturbation theory (DFPT), many-body perturbation theory (GW approximation and Bethe-Salpeter equation), and more specific or advanced formalisms, such as dynamical mean-field theory (DMFT) and the "temperature-dependent effective potential" approach for anharmonic effects. Relying on planewaves for the representation of wavefunctions, density, and other space-dependent quantities, with pseudopotentials or projector-augmented waves (PAWs), it is well suited for the study of periodic materials, although nanostructures and molecules can be treated with the supercell technique. The present article starts with a brief description of the project, a summary of the theories upon which abinit relies, and a list of the associated capabilities. It then focuses on selected capabilities that might not be present in the majority of electronic structure packages either among planewave codes or, in general, treatment of strongly correlated materials using DMFT; materials under finite electric fields; properties at nuclei (electric field gradient, Mössbauer shifts, and orbital magnetization); positron annihilation; Raman intensities and electro-optic effect; and DFPT calculations of response to strain perturbation (elastic constants and piezoelectricity), spatial dispersion (flexoelectricity), electronic mobility, temperature dependence of the gap, and spin-magnetic-field perturbation. The abinit DFPT implementation is very general, including systems with van der Waals interaction or with noncollinear magnetism. Community projects are also described: generation of pseudopotential and PAW datasets, high-throughput calculations (databases of phonon band structure, second-harmonic generation, and GW computations of bandgaps), and the library libpaw. abinit has strong links with many other software projects that are briefly mentioned.