129 research outputs found
Control de la madurez en frutos por medio de ensayos de impacto.
En anteriores trabajos se ha observado que la respuesta de los frutos a un impacto mecánico está muy influida por su estado de madurez. Se realizaron ensayos de impacto sobre peras cv. Limonera, a lo largo de 12 semanas de conservación frigorífica y de maduración controlada. El impacto desde 4 cm de altura (equivalente a 0,02 J) resulta no destructivo y puede utilizarse para la determinación del estado de madurez de estos frutos. Por métodos de regresión lineal múltiple sobre los 15 para metros del impacto más representativos se obtienen buenas p r e dicciones de la madurez, representada por la fuerza de corte de probetas de pulpa, FC (N)
Spanish Dentists’ Awareness, Knowledge, and Practice Regarding COVID-19: A Multiple Regression Analysis
The authors thank the Spanish Society of Epidemiology and
Oral Public Health (SESPO) for expert supervision of the questionnaire;
the Spanish General Council of Dentists (GCD) and
the Spanish societies of dental hygienists for their rapid dissemination
of the survey to their members.Introduction: During the first months of the coronavirus disease 2019 (COVID-19) pandemic,
Spain had the highest mortality rate and the second-highest infection rate in the world.
Objective: To analyze the occupational situation of dentists, hygienists, and dental auxiliary
staff during the peak of the pandemic, after the state of alarm was declared in Spain, and
when the state of alarm was declared. In addition, a possible relationship between the geographical
distribution of infected people and the availability of individual protection systems
was investigated.
Material and Methods: A cross-sectional questionnaire was answered by 6470 dentists and
dental staff via WhatsApp and social media.
Results: A total of 1 in 4 dental professionals ceased working completely. Of those that kept
working, 25.28% of dentists and 19.61% of hygienist-auxiliary were equipped with filtering
face piece (FFP) 2 masks (P < .05), and 61.8% complied with the official protection recommendations
set by the General Council of Dentists of Spain. Nearly 59.4% of respondents had
symptoms, but only 1.5% of dentists were tested, with 14% of dentists in isolation at the time
of response. Overall, it is suggested that 10% of dental professionals may have been in direct
contact with the coronavirus.
Conclusions: Direct contact of Spanish dental health professionals with severe acute respiratory
syndrome coronavirus disease 2 (SARS CoV-2) has been high during the most active phase
of the pandemic. Dental professionals did not have personal protective equipment (PPE) necessary
to care for patients, a situation that justified the reduction in scheduled dental care and
only emergencies being treated. The Spanish geographical regions with the highest number of
contagions had the least amount of individual protective resources (FFP2 and FFP3masks)
High-pressure/high-temperature phase diagram of zinc
The phase diagram of zinc (Zn) has been explored up to 140 GPa and 6000K, by combining optical observations, x-ray diffraction, and ab initio calculations. In the pressure range covered by this study, Zn is found to retain a hexagonal close-packed (hcp) crystal symmetry up to the melting temperature. The known decrease of the axial ratio (c/a) of the hcp phase of Zn under compression is observed in x-ray diffraction experiments from 300K up to the melting temperature. The pressure at which c/a reaches root 3 (approximate to 10GPa) is slightly affected by temperature. When this axial ratio is reached, we observed that single crystals of Zn, formed at high temperature, break into multiple poly-crystals. In addition, a noticeable change in the pressure dependence of c/a takes place at the same pressure. Both phenomena could be caused by an isomorphic second-order phase transition induced by pressure in Zn. The reported melt curve extends previous results from 24 to 135 GPa. The pressure dependence obtained for the melting temperature is accurately described up to 135 GPa by using a Simon-Glatzel equation: T-m = 690 K(1 + P/10.5 GPa)(0.76), where P is the pressure in GPa. The determined melt curve agrees with previous low-pressure studies and with shock-wave experiments, with a melting temperature of 5060(30) K at 135 GPa. Finally, a thermal equation of state is reported, which at room-temperature agrees with the literature.The authors are thankful for the financial support to this research from the Spanish Ministerio de Economía y Competitividad, the Spanish Research Agency, and the European Fund for Regional Development under Grant Nos. MAT2016-
75586-C4-1-P, and MAT2015-71070-REDC (MALTA Consolider). British Crown Owned Copyright 2018/AWE.Peer reviewe
A baixa procura pela licenciatura em física, com base em depoimentos de estudantes do ensino médio público do oeste catarinense
Derivative UV/Vis spectroelectrochemistry in a thin-layer regime: deconvolution and simultaneous quantification of ascorbic acid, dopamine and uric acid
In this work, UV/Vis spectroelectrochemistry (SEC), in a thin-layer regime and parallel configuration, is selected to solve a
complex mixture that contains dopamine (DA), ascorbic acid (AA) and uric acid (UA). These molecules, like many other
biological compounds, are assuming a highly important place in analytical and biomedical fields due to the fundamental role
that they play in human metabolism. In addition, low or high levels of these compounds are associated with diseases such as
Parkinson’s disease. For this reason, the quantification of these biomolecules is becoming increasingly critical. However, some
drawbacks must be overcome, because the three molecules coexist in the human body, and the species are subject to mutual
interference. In fact, they are all oxidized at similar potentials, and their UV/Vis absorption bands overlap, greatly complicating
their quantification. For this reason, derivative SEC together with suitable chemometric tools such as PARAFAC are proposed to
solve this complex matrix. This technique allows us to separate the contribution of each of these molecules present in a sample
and to quantify all of them, achieving high resolution and reproducibility. Besides, detection limits at the micromolar level are
achieved for DA, AA and UA in mixture solutions. This work thus demonstrates the great potential for derivative potentiodynamic
SEC combined with the appropriate chemometric tools in solving complex mixtures, a field where SEC is still taking the
first steps.Ministerio de Economía y Competitividad (Grants CTQ2017-83935-RAEI/
FEDER, UE), Junta de Castilla y León (Grant BU297P18) and
Ministerio de Ciencia, Innovación y Universidades (RED2018-102412-
T). F.O. is grateful for the contract funded by Junta de Castilla y León, the
European Social Fund and the Youth Employment Initiative. J.G.R.
thanks theMinisterio de Economía y Competitividad for his postdoctoral
contract (CTQ2017-83935-R AEI/FEDER, UE)
Breast cancer in systemic lupus
OBJECTIVE: There is a decreased breast cancer risk in SLE versus the general population. We assessed a large sample of SLE patients, evaluating demographic and clinical characteristics and breast cancer risk. METHODS: We performed case-cohort analyses within a multi-centre international SLE sample. We calculated the breast cancer hazard ratio (HR) in female SLE patients, relative to demographics, reproductive history, family history of breast cancer, and time-dependent measures of anti-dsDNA positivity, cumulative disease activity, and drugs, adjusted for SLE duration. RESULTS: There were 86 SLE breast cancers and 4,498 female SLE cancer-free controls. Patients were followed on average for 7.6 years. Versus controls, SLE breast cancer cases tended to be white and older. Breast cancer cases were similar to controls regarding anti-dsDNA positivity, disease activity and most drug exposures over time. In univariate and multivariate models, the principal factor associated with breast cancers was older age at cohort entry. CONCLUSIONS: There was little evidence that breast cancer risk in this SLE sample was strongly driven by any of the clinical factors that we studied. Further search for factors that determine the lower risk of breast cancer in SLE may be warranted
Clinical factors associated with a Candida albicans Germ Tube Antibody positive test in Intensive Care Unit patients
Background: Poor outcomes of invasive candidiasis (IC) are associated with the difficulty in establishing the microbiological diagnosis at an early stage. New scores and laboratory tests have been developed in order to make an early therapeutic intervention in an attempt to reduce the high mortality associated with invasive fungal infections. Candida albicans IFA IgG has been recently commercialized for germ tube antibody detection (CAGTA). This test provides a rapid and simple diagnosis of IC (84.4% sensitivity and 94.7% specificity). The aim of this study is to identify the patients who could be benefited by the use of CAGTA test in critical care setting.
Methods: A prospective, cohort, observational multicentre study was carried out in six medical/surgical Intensive care units (ICU) of tertiary-care Spanish hospitals. Candida albicans Germ Tube Antibody test was performed twice a week if predetermined risk factors were present, and serologically demonstrated candidiasis was considered if the testing serum dilution was >= 1: 160 in at least one sample and no other microbiological evidence of invasive candidiasis was found.
Results: Fifty-three critically ill non-neutropenic patients (37.7% post surgery) were included. Twenty-two patients (41.5%) had CAGTA-positive results, none of them with positive blood culture for Candida. Neither corrected colonization index nor antifungal treatment had influence on CAGTA results. This finding could corroborate that the CAGTA may be an important biomarker to distinguish between colonization and infection in these patients. The presence of acute renal failure at the beginning of the study was more frequent in CAGTA-negative patients. Previous surgery was statistically more frequent in CAGTA-positive patients.
Conclusions: This study identified previous surgery as the principal clinical factor associated with CAGTA-positive results and emphasises the utility of this promising technique, which was not influenced by high Candida colonization or antifungal treatment. Our results suggest that detection of CAGTA may be important for the diagnosis of invasive candidiasis in surgical patients admitted in ICU.This study has been supported by a Pfizer research gran
Relationship between olive oil consumption and ankle-brachial pressure index in a population at high cardiovascular risk
The aim of this study was to ascertain the association between the consumption of different categories of edible olive oils (virgin olive oils and olive oil) and olive pomace oil and ankle-brachial pressure index (ABI) in participants in the PREDIMED-Plus study, a trial of lifestyle modification for weight and cardiovascular event reduction in individuals with overweight/obesity harboring the metabolic syndrome.
Methods: We performed a cross-sectional analysis of the PREDIMED-Plus trial. Consumption of any category of olive oil and olive pomace oil was assessed through a validated food-frequency questionnaire. Multivariable linear regression models were fitted to assess associations between olive oil consumption and ABI. Additionally, ABI ≤1 was considered as the outcome in logistic models with different categories of olive oil and olive pomace oil as exposure.
Results: Among 4330 participants, the highest quintile of total olive oil consumption (sum of all categories of olive oil and olive pomace oil) was associated with higher mean values of ABI (beta coefficient: 0.014, 95% confidence interval [CI]: 0.002, 0.027) (p for trend = 0.010). Logistic models comparing the consumption of different categories of olive oils, olive pomace oil and ABI ≤1 values revealed an inverse association between virgin olive oils consumption and the likelihood of a low ABI (odds ratio [OR] 0.73, 95% CI [0.56, 0.97]), while consumption of olive pomace oil was positively associated with a low ABI (OR 1.22 95% CI [1.00, 1.48]).
Conclusions: In a Mediterranean population at high cardiovascular risk, total olive oil consumption was associated with a higher mean ABI. These results suggest that olive oil consumption may be beneficial for peripheral artery disease prevention, but longitudinal studies are needed
Bauru School of Dentistry Tele-Health League: an educational strategy applied to research, teaching and extension among applications in tele-health
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