1,384 research outputs found
Glycerol Valorization towards a Benzoxazine Derivative through a Milling and Microwave Sequential Strategy
Glycerol and aminophenol intermolecular condensation has been investigated through a
milling and microwave-assisted sequential strategy, towards the synthesis of a benzoxaxine derivative.
Mechanochemical activation prior to the microwave-assisted process could improve the probability
of contact between the reagents, and greatly favors the higher conversion of aminophenol. At the
same time, following a mechanochemical–microwave sequential approach could tune the selectivity
towards the formation of a benzoxazine derivative, which could find application in a wide range of
biomedical area
Safety monitoring of cytostatic handling
Context: The Institute of Oncology and Radiobiology (INOR) is the leading institution for the diagnosis, treatment and follow up of cancer in Cuba. Cancer treatment is mainly by three methods: surgery, radiotherapy and chemotherapy. Pharmacological treatments involve the use of dangerous substances such as cytostatics, the handling of which threat the health of the occupationally exposed staff.
Aims: To evaluate a biomarker of genotoxicity indicative of DNA damage in the biomonitoring of occupational risks associated with the administration of antineoplastic drugs to hospitalized patients.
Methods: The determination of the frequency of micronuclei, in cells of the exfoliated oral mucosa was determined (Micronucleus test) in subjects who administer cytostatic drugs at the institute and a control group formed by administrative personal.
Results: Present results evidenced that all exposed subjects possess the same DNA damage that non-exposed-ones. Such results are in concordance with the proper use of primary protection barriers and the adhesion to normalized operational procedures.
Conclusions: The frequency of micronuclei is a useful biomarker for assessing DNA damage associated with the administration of antineoplastic drugs. The risk perception analysis (RISKPERCEP) in occupationally exposed subjects complements the occupational safety monitoring
Influencia del grado de deformación en frío en el tamaño de grano y en la resistencia a la corrosión del acero F-1110
En este trabajo se ha estudiado la evolución que sufre el tamaño de grano del acero al carbono F-1110 para distintos grados de deformación en frío, a partir de su estado de recocido, libre de tensiones y de cualquier acritud. La deformación en frío se ha conseguido utilizando una máquina universal de ensayos y los distintos grados de deformación se han ajustado al intervalo comprendido entre la estricción y la rotura. La posterior observación al microscopio óptico de las zonas deformadas, previa preparación metalográfica, nos ha permitido medir la variación en el tamaño de grano. Finalmente, se ha evaluado la influencia del grado de deformación en la resistencia a la corrosión del acero
Machine learning methods applied to combined Raman and LIBS spectra: Implications for mineral discrimination in planetary missions
Producción CientíficaThe combined analysis of geological targets by complementary spectroscopic techniques could enhance the characterization of the mineral phases found on Mars. This is indeed the case with the SuperCam instrument onboard the Perseverance rover. In this framework, the present study seeks to evaluate and compare multiple machine learning techniques for the characterization of carbonate minerals based on Raman-LIBS (Laser-Induced Breakdown Spectroscopy) spectroscopic data. To do so, a Ca-Mg prediction curve was created by mixing hydromagnesite and calcite at different concentration ratios. After their characterization by Raman and LIBS spectroscopy, different multivariable machine learning (Gaussian process regression, support vector machines, ensembles of trees, and artificial neural networks) were used to predict the concentration ratio of each sample from their respective datasets. The results obtained by separately analyzing Raman and LIBS data were then compared to those obtained by combining them. By comparing their performance, this work demonstrates that mineral discrimination based on Gaussian and ensemble methods optimized the combine of Raman-LIBS dataset outperformed those ensured by Raman and LIBS data alone. This demonstrated that the fusion of data combination and machine learning is a promising approach to optimize the analysis of spectroscopic data returned from Mars.Agencia Estatal de Investigación, grant (PID2022-142490OB-C32)Ministerio de Economía y Competitividad (MINECO),Grant/Award Number (RDE2018-102600-T
Clinical and ultrasound thyroid nodule characteristics and their association with cytological and histopathological outcomes: A retrospective multicenter study in high-resolution thyroid nodule clinics
Introduction: Thyroid nodules are a common finding. A high-resolution thyroid nodule
clinic (HR-TNC) condenses all tests required for the evaluation of thyroid nodules into a single
appointment. We aimed to evaluate the clinical outcomes at HR-TNCs. Design and Methods:
A retrospective cross-sectional multicenter study including data from four HR-TNCs in Spain.
We evaluated fine-needle aspiration (FNA) indications and the association between clinical and
ultrasound characteristics with cytological and histopathological outcomes. Results: A total of 2809
thyroid nodules were included; FNA was performed in 82.1%. Thyroid nodules that underwent
FNA were more likely larger, isoechoic, with microcalcifications, and in younger subjects. The rate
of nondiagnostic FNA was 4.3%. A solid component, irregular margins or microcalcifications,
significantly increased the odds of Bethesda IV-V-VI (vs. Bethesda II). Irregular margins and a solid
component were independently associated with increased odds of malignancy. Thyroid nodules
<20 mm and ≥20–<40 mm had a 6.5-fold and 3.3-fold increased risk for malignancy respectively
in comparison with those ≥40 mm. Conclusion: In this large multicenter study, we found that the
presence of a solid component and irregular margins are factors independently related to malignancy
in thyroid nodules. Since nodule size ≥40 mm was associated with the lowest odds of malignancy,
this cut-off should not be a factor leading to indicate thyroid surgery. HR-TNCs were associated with
a low rate of nondiagnostic FNA
Usefulness of two independent DNA and rna tissue-based multiplex assays for the routine care of advanced NSCLC patients
Personalized medicine is nowadays a paradigm in lung cancer management, offering important benefits to patients. This study aimed to test the feasibility and utility of embedding two multiplexed genomic platforms as the routine workup of advanced non-squamous non-small cell lung cancer (NSCLC) patients. Two parallel multiplexed approaches were performed based on DNA sequencing and direct digital detection of RNA with nCounter® technology to evaluate gene mutations and fusions. The results were used to guide genotype-directed therapies and patient outcomes were collected. A total of 224 advanced non-squamous NSCLC patients were prospectively included in the study. Overall, 85% of samples were successfully characterized at DNA and RNA levels and oncogenic drivers were found in 68% of patients, with KRAS, EGFR, MET∆ex14, BRAF, and ALK being the most frequent (31%, 19%, 5%, 4%, and 4%, respectively). Among all patients with complete genotyping results and follow-up data (n = 156), the median overall survival (OS) was 1.90 years (confidence interval (CI) 95% 1.69-2.10) for individuals harbouring an actionable driver treated with a matched therapy, compared with 0.59 years (CI 95% 0.39-0.79) in those not eligible for any targeted therapy and 0.61 years (CI 95% 0.12-1.10) in patients with no drivers identified (p < 0.001). Integrating DNA and RNA multiplexing technologies into the routine molecular testing of advanced NSCLC patients is feasible and useful and highlights the necessity of widespread integrating comprehensive molecular diagnosis into lung cancer care
Investigation of the splitting of quark and gluon jets
The splitting processes in identified quark and gluon jets are investigated using longitudinal and transverse observables. The jets are selected from symmetric three-jet events measured in Z decays with the Delphi detector in 1991-1994. Gluon jets are identified using heavy quark anti-tagging. Scaling violations in identified gluon jets are observed for the first time. The scale energy dependence of the gluon fragmentation function is found to be about two times larger than for the corresponding quark jets, consistent with the QCD expectation TeX . The primary splitting of gluons and quarks into subjets agrees with fragmentation models and, for specific regions of the jet resolution TeX , with NLLA calculations. The maximum of the ratio of the primary subjet splittings in quark and gluon jets is TeX . Due to non-perturbative effects, the data are below the expectation at small TeX . The transition from the perturbative to the non-perturbative domain appears at smaller TeX for quark jets than for gluon jets. Combined with the observed behaviour of the higher rank splittings, this explains the relatively small multiplicity ratio between gluon and quark jets
COVID-19 anxiety, psychological well-being and preventive behaviors during the COVID-19 pandemic in Latin America and the Caribbean: relationships and explanatory model
This study assesses the relationship between COVID-19 anxiety and subjective well-being in terms of the mediating role of COVID-19 preventive behaviors. Additionally, the contribution of sociodemographic factors (sex and age) and risk perception on COVID-19 anxiety and its potential measurement invariance was tested in 5655 participants from 12 countries in Latin America and the Caribbean. A mixture of both latent and observable variables were analyzed using a system of structural equations. The Coronavirus Anxiety Scale (CAS), Preventive COVID-19 Infection Behaviors Scale (PCIBS) and single-item measures were used to assess the perceived probability of death, perceived severity and concern about transmitting COVID-19. The results indicated that there is a significant and relevant direct effect of COVID-19 anxiety on participants' well-being. Furthermore, COVID-19 anxiety significantly predicted both preventive behavior (β = .29, p < .01) and well-being (β = –.32, p < .01). The effects of COVID anxiety and preventive behavior explained 9.8% of the variance in well-being (R-square = .098); whereas, 8.4% of the variance in preventive behavior was associated with COVID anxiety (R-square = .084). Likewise, perceived likelihood of death from COVID, perceived severity of COVID, and concerns about COVID transmission were positively related to anxiety. Age was negatively related to anxiety, with men being less anxious than women. The results are invariant by country, i.e., the broad relationships found in the combined sample are also present in each individual country. The findings indicate that, although the exact relationships between variables may vary between countries, there are enough similarities to provide useful information about the impact of the COVID-19 pandemic in each of the countries included in the study
- …