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1.
Comput Biol Med ; 175: 108548, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718666

RESUMO

The aim of this work is to develop and evaluate a deep classifier that can effectively prioritize Emergency Medical Call Incidents (EMCI) according to their life-threatening level under the presence of dataset shifts. We utilized a dataset consisting of 1982746 independent EMCI instances obtained from the Health Services Department of the Region of Valencia (Spain), with a time span from 2009 to 2019 (excluding 2013). The dataset includes free text dispatcher observations recorded during the call, as well as a binary variable indicating whether the event was life-threatening. To evaluate the presence of dataset shifts, we examined prior probability shifts, covariate shifts, and concept shifts. Subsequently, we designed and implemented four deep Continual Learning (CL) strategies-cumulative learning, continual fine-tuning, experience replay, and synaptic intelligence-alongside three deep CL baselines-joint training, static approach, and single fine-tuning-based on DistilBERT models. Our results demonstrated evidence of prior probability shifts, covariate shifts, and concept shifts in the data. Applying CL techniques had a statistically significant (α=0.05) positive impact on both backward and forward knowledge transfer, as measured by the F1-score, compared to non-continual approaches. We can argue that the utilization of CL techniques in the context of EMCI is effective in adapting deep learning classifiers to changes in data distributions, thereby maintaining the stability of model performance over time. To our knowledge, this study represents the first exploration of a CL approach using real EMCI data.


Assuntos
Aprendizado Profundo , Humanos , Bases de Dados Factuais , Espanha , Serviços Médicos de Emergência
3.
Gac Sanit ; 2024 Apr 02.
Artigo em Espanhol | MEDLINE | ID: mdl-38653640

RESUMO

OBJECTIVE: To analyze the prevalence of burnout syndrome in physicians working in Spain through a systematic review with meta-analysis METHOD: We searched PubMed/MEDLINE, Embase, and PsycINFO (up to June 2023). Observational studies conducted in Spain reporting the prevalence of burnout in physicians were included. From each study, methodological characteristics and results were extracted, and their quality was evaluated. We performed a narrative synthesis with random effects meta-analysis to calculate proportions. RESULTS: Sixty-seven studies with 16,076 participants were included. For the primary outcome, the meta-analysis revealed a global prevalence of burnout in physicians of 24% (95%CI: 19%-29%; 46 studies; 8821 participants; I2=97%). From subgroup analysis, differences were observed depending on the diagnostic criteria used: 18% (95%CI: 13%-23%) for three dimensions of burnout, 29% (95%CI: 24%-34%) for two dimensions and 51% (95%CI: 42%-60%) for one dimension. The heterogeneity between studies could not be fully explained through additional analyses where non-statistically significant differences were found with other variables (e.g., study quality, setting, professional category or medical specialty). CONCLUSIONS: A high prevalence of burnout syndrome was found in physicians working in Spain. These results can contribute to estimating the burden associated with burnout in physicians at a national level and to the design of future studies. Strategies appear to be necessary to prevent and mitigate this situation. PROTOCOL REGISTRATION: Open Science Framework: https://osf.io/b2h4m/.

4.
Sci Data ; 10(1): 872, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057322

RESUMO

In the summer of 2012, two fires affected Mediterranean ecosystems in the eastern Iberian Peninsula. The size of these fires was at the extreme of the historical variability (megafires). Animals are traditionally assumed to recolonize from source populations outside of the burned area (exogenous regeneration) while plants recover from endogenous regeneration (resprouting and seeding). However, there is increasing evidence of in situ fire survival in animals. To evaluate the effect of large-scale fires on biodiversity and the mechanism of recovery, in 2013, we set up 12 plots per fire, covering burned vegetation at different distances from the fire perimeter and unburned vegetation. In each plot, we followed the postfire recovery of arthropods, reptiles (including some of their parasites), and plants for 2 to 5 years. Here we present the resulting database (POSTDIV) of taxon abundance. POSTDIV totals 19,906 records for 457 arthropod taxa (113,681 individuals), 12 reptile taxa (503 individuals), 4 reptile parasites (234 individuals), and 518 plant taxa (cover-abundance). We provide examples in the R language to query the database.


Assuntos
Artrópodes , Incêndios , Animais , Biodiversidade , Ecossistema , Plantas , Répteis , Bases de Dados Factuais
5.
Sensors (Basel) ; 23(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37299764

RESUMO

The characterization of suspended dust near the Martian surface is extremely relevant to understand the climate of Mars. In this frame, a Dust Sensor instrument, an infrared device designed to obtain the effective parameters of Martian dust using the scattering properties of the dust particles, was developed. The purpose of this article is to present a novel methodology to calculate, from experimental data, an instrumental function of the Dust Sensor that allows solving the direct problem and providing the signal that this instrument would provide given a distribution of particles. The experimental method is based on recording the signal measured when a Lambertian reflector is gradually introduced into the interaction volume at different distances from the detector and source and applying tomography techniques (inverse Radon transform) to obtain the image of a section of the interaction volume. This method provides a complete mapping of the interaction volume experimentally, which determines the Wf function. The method was applied to solve a specific case study. Among the advantages of this method, it should be noted that it avoids assumptions and idealizations of the dimensions of the volume of interaction and reduces the time required to carry out simulations.


Assuntos
Poeira , Marte , Poeira/análise , Meio Ambiente Extraterreno , Calibragem
6.
J Contam Hydrol ; 255: 104142, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739845

RESUMO

This work presents a novel technique consisting in the use of yield stress fluids as blocking agents in porous media presenting pore-scale heterogeneities. The key feature of this method is that yield stress fluids only flow through the pores having a minimum size that depends on the applied pressure gradient. These fluids remain immobile in more and more pores as the pressure gradient is decreased. Therefore, the dimension of the pores which are invaded by the yield stress fluid can be controlled by adjusting the applied pressure gradient. Moreover, yield stress fluids are highly suitable blocking agents given the extremely high viscosity values that they exhibit in the pores. This allows for the diversion of the flow from greater to smaller pores during subsequent waterflooding stages, thus enhancing pollutant removal from the flow paths of small hydraulic conductance. A series of multiphase flow experiments were conducted in this study using well-characterized cores of artificial A10 sintered silicate. In these experiments, semidilute aqueous solutions of xanthan gum biopolymer were used as yield stress fluids to block the greatest pores. By doing so, considerably more pollutant was recovered by waterflooding. Furthermore, it was shown that an increase in polymer concentration does not always lead to a decrease in the size of the pores invaded by the blocking agent. Indeed, concentrated polymer solutions generate higher pressure gradients throughout the porous medium, which facilitates the invasion of small pores. Nevertheless, depending on the value of the yield stress-pressure gradient ratio, they may also develop extremely high viscosities that slow down their flow through such small pores. This work also presents a method to measure the volume of blocked pores using the results of tracer tests. The reported results suggest that using a polymer solution developing a yield stress as a selective blocking agent is a promising technique for soil remediation.


Assuntos
Poluentes Ambientais , Poluição Ambiental , Porosidade , Polímeros , Solo
7.
Sensors (Basel) ; 22(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36501918

RESUMO

Suspended dust above the Martian surface is an important element in Martian climatology. In the frame of the Exomars'22 mission, we developed a dust sensor instrument, designed to provide size parameters of dust particles suspended in Mars surface from the light scattered by the particles. Thus, to interpret the data of the dust sensor, we need a method to calculate the theoretical optical power dispersed by the particles and, therefore, the theoretical signal obtained by the instrument. This signal depends on the suspended particles and on the instrument configuration. In this paper, we present a new method to calculate the angular weighting function (Wf) for scattering sensors. Wf encompasses the scattering angles measured by the sensor and depends only on the instrument and not on the suspended particles. To calculate this Wf, we use fundamental radiometry principles and an appropriate coordinate system, where one coordinate is the scattering angle. The method is applied to the dust sensor instrument and compared with other methods. The comparison highlights the advantages of the proposed method since it avoids using an ideal sampling volume, preserves the radiometric meaning, and avoids instrument calibration. The effectiveness of the method makes it a valuable tool for the design of scattering instruments and also for the interpretation of their data.

8.
Nutrients ; 14(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36432405

RESUMO

Subclinical mastitis (SCM) is an inflammatory state of the lactating mammary gland, which is asymptomatic and may have negative consequences for child growth. The objectives of this study were to: (1) test the association between the dietary inflammatory index (DII®) and SCM and (2) assess the differences in nutrient intakes between women without SCM and those with SCM. One hundred and seventy-seven women with available data on human milk (HM) sodium potassium ratio (Na:K) and dietary intake data were included for analysis. Multivariable logistic regression was used to examine the association between nutrient intake and the DII score in relation to SCM. Women without SCM had a lower median DII score (0.60) than women with moderate (1.12) or severe (1.74) SCM (p < 0.01). A one-unit increase in DII was associated with about 41% increased odds of having SCM, adjusting for country and mode of delivery, p = 0.001. Women with SCM had lower mean intakes of several anti-inflammatory nutrients. We show for the first time exploratory evidence that SCM may be associated with a pro-inflammatory diet and women with SCM have lower intakes of several antioxidant and anti-inflammatory nutrients.


Assuntos
Lactação , Mastite , Feminino , Humanos , Dieta , Mastite/complicações , Leite Humano/química , Sódio/análise
9.
Stud Health Technol Inform ; 294: 859-863, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35612226

RESUMO

The objective of this work was to discover key topics latent in free text dispatcher observations registered during emergency medical calls. We used a total of 1374931 independent retrospective cases from the Valencian emergency medical dispatch service in Spain, from 2014 to 2019. Text fields were preprocessed to reduce vocabulary size and filter noise, removing accent and punctuation marks, along with uninformative and infrequent words. Key topics were inferred from the multinomial probabilities over words conditioned on each topic from a Latent Dirichlet Allocation model, trained following an online mini-batch variational approach. The optimal number of topics was set analyzing the values of a topic coherence measure, based on the normalized pointwise mutual information, across multiple validation K-folds. Our results support the presence of 15 key topics latent in free text dispatcher observations, related with: ambulance request; chest pain and heart attack; respiratory distress; head falls and blows; fever, chills, vomiting and diarrhea; heart failure; syncope; limb injuries; public service body request; thoracic and abdominal pain; stroke and blood pressure abnormalities; pill intake; diabetes; bleeding; consciousness. The discovery of these topics implies the automatic characterization of a huge volume of complex unstructured data containing relevant information linked to emergency medical call incidents. Hence, results from this work could lead to the update of structured emergency triage algorithms to directly include this latent information in the triage process, resulting in a positive impact in patient wellbeing and health services sustainability.


Assuntos
Despacho de Emergência Médica , Serviços Médicos de Emergência , Ambulâncias , Sistemas de Comunicação entre Serviços de Emergência , Humanos , Estudos Retrospectivos , Triagem
10.
Sensors (Basel) ; 21(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34640826

RESUMO

The need to monitor specific areas for different applications requires high spatial and temporal resolution. This need has led to the proliferation of ad hoc systems on board nanosatellites, drones, etc. These systems require low cost, low power consumption, and low weight. The work we present follows this trend. Specifically, this article evaluates a method to determine the cloud map from the images provided by a simple bi-spectral infrared camera within the framework of JEM-EUSO (The Joint Experiment Missions-Extrem Universe Space Observatory). This program involves different experiments whose aim is determining properties of Ultra-High Energy Cosmic Ray (UHECR) via the detection of atmospheric fluorescence light. Since some of those projects use UV instruments on board space platforms, they require knowledge of the cloudiness state in the FoV of the instrument. For that reason, some systems will include an infrared (IR) camera. This study presents a test to generate a binary cloudiness mask (CM) over the ocean, employing bi-spectral IR data. The database is created from Moderate-Resolution Imaging Spectroradiometer (MODIS) data (bands 31 and 32). The CM is based on a split-window algorithm. It uses an estimation of the brightness temperature calculated from a statistical study of an IR images database along with an ancillary sea surface temperature. This statistical procedure to obtain the estimate of the brightness temperature is one of the novel contributions of this work. The difference between the measured and estimation of the brightness temperature determines whether a pixel is cover or clear. That classification requires defining several thresholds which depend on the scenarios. The procedure for determining those thresholds is also novel. Then, the results of the algorithm are compared with the MODIS CM. The agreement is above 90%. The performance of the proposed CM is similar to that of other studies. The validation also shows that cloud edges concentrate the vast majority of discrepancies with the MODIS CM. The relatively high accuracy of the algorithm is a relevant result for the JEM-EUSO program. Further work will combine the proposed algorithm with complementary studies in the framework of JEM-EUSO to reinforce the CM above the cloud edges.

11.
Artif Intell Med ; 117: 102088, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34127234

RESUMO

The objective of this work was to develop a predictive model to aid non-clinical dispatchers to classify emergency medical call incidents by their life-threatening level (yes/no), admissible response delay (undelayable, minutes, hours, days) and emergency system jurisdiction (emergency system/primary care) in real time. We used a total of 1 244 624 independent incidents from the Valencian emergency medical dispatch service in Spain, compiled in retrospective from 2009 to 2012, including clinical features, demographics, circumstantial factors and free text dispatcher observations. Based on them, we designed and developed DeepEMC2, a deep ensemble multitask model integrating four subnetworks: three specialized to context, clinical and text data, respectively, and another to ensemble the former. The four subnetworks are composed in turn by multi-layer perceptron modules, bidirectional long short-term memory units and a bidirectional encoding representations from transformers module. DeepEMC2 showed a macro F1-score of 0.759 in life-threatening classification, 0.576 in admissible response delay and 0.757 in emergency system jurisdiction. These results show a substantial performance increase of 12.5 %, 17.5 % and 5.1 %, respectively, with respect to the current in-house triage protocol of the Valencian emergency medical dispatch service. Besides, DeepEMC2 significantly outperformed a set of baseline machine learning models, including naive bayes, logistic regression, random forest and gradient boosting (α = 0.05). Hence, DeepEMC2 is able to: 1) capture information present in emergency medical calls not considered by the existing triage protocol, and 2) model complex data dependencies not feasible by the tested baseline models. Likewise, our results suggest that most of this unconsidered information is present in the free text dispatcher observations. To our knowledge, this study describes the first deep learning model undertaking emergency medical call incidents classification. Its adoption in medical dispatch centers would potentially improve emergency dispatch processes, resulting in a positive impact in patient wellbeing and health services sustainability.


Assuntos
Despacho de Emergência Médica , Teorema de Bayes , Sistemas de Comunicação entre Serviços de Emergência , Serviço Hospitalar de Emergência , Humanos , Estudos Retrospectivos
12.
J Colloid Interface Sci ; 590: 446-457, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33561594

RESUMO

During the flow of non-Newtonian fluids in porous media, the relationships between macroscopic quantities are governed by extremely complex microscopic fluid dynamics resulting from solid-fluid interactions. Consequently, the Darcy-scale viscosity exhibited by a shear-thinning fluid depends on the injection velocity, contrarily to the case of Newtonian fluids. In the present work, pore network modelling is used to investigate the relationships between local and macroscopic viscosities during the flow of shear-thinning fluids in 3D porous media. Special efforts are devoted to 1) identifying the influence of the viscosity exhibited by the fluid within the constrictions of the preferential flow paths on the value of Darcy-scale viscosity and 2) proposing an analytical expression to upscale viscosity from the local viscosity values. To go further, the reduction in average hydraulic tortuosity stemming from the directional nature of shear-thinning behavior in 3D porous media will also be quantified. The results of the present study show that Darcy-scale viscosity can be accurately calculated as the flow-rate weighted average of local viscosities in the investigated media. Moreover, the velocity maps provided by the proposed pore network flow simulations are suitable to assess hydraulic tortuosity reduction as compared to the flow of a Newtonian fluid.

13.
Am J Clin Nutr ; 113(2): 370-379, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33330899

RESUMO

BACKGROUND: Epidemiological studies have reported lower risk of cardiovascular disease with moderate coffee consumption. In addition, emerging evidence indicates that consumption of coffee beverages enriched in chlorogenic acids (CGAs) may influence blood pressure and endothelial function, suggesting that the beneficial cardiovascular effect of coffee may relate to its CGA content. OBJECTIVES: We conducted a double-blind randomized crossover trial to test the effect of acute consumption of a decaffeinated green coffee extract (DGCE), rich in CGAs, on endothelial function in healthy subjects. METHODS: We compared 3 different doses of DGCE (302, 604, and 906 mg, respectively) with a placebo. Endothelial function was defined as the percentage change in the internal diameter of the brachial artery in response to flow-mediated dilation (%FMD). In addition, we followed the plasma concentration-time profiles of 25 systemic CGA metabolites over 24 h after DGCE consumption and we explored the relation between systemic concentrations of CGAs and the effect on %FMD. RESULTS: The DGCE formulations containing different amounts of CGAs resulted in dose-proportional increases in overall total polyphenol concentrations. The systemic appearance of total CGAs was biphasic, in agreement with previous results suggesting 2 sites of absorption in the gastrointestinal tract. Compared with the placebo group, a significant FMD increase (>1%) was observed 8.5, 10, and 24 h after consumption of 302 mg DGCE (∼156.4 mg CGAs). The differences with placebo observed in the other 2 groups were not statistically significant. Evaluation of the relation between phenolic exposure and %FMD showed a positive tendency toward a larger effect at higher concentrations and different behavior of CGA metabolites depending on the conjugated chemical position. CONCLUSIONS: We demonstrated an acute improvement in %FMD over time after ingestion of a DGCE, explained at least partly by the presence in the blood circulation of CGAs and their metabolites. This trial was registered at clinicaltrials.gov as NCT03520452.


Assuntos
Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/administração & dosagem , Coffea/química , Vasodilatação/efeitos dos fármacos , Ácido Clorogênico/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Hidroxibenzoatos/química , Masculino , Pessoa de Meia-Idade
14.
Clin Nutr ; 40(1): 222-228, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534950

RESUMO

Differences in vitamin and carotenoids content of human milk (HM) produced for infants born at term and preterm is poorly understood. In this study, HM was collected weekly for four and two months post-partum for preterm and term groups, respectively. Nutrients of interest, from single full breast expressions were measured by liquid chromatography coupled with mass spectrometry. Microbiological assay was employed for vitamin B12. When compared at equivalent post-partum age, vitamins B1, B2, B6, and B9 were significantly higher in preterm than in term HM, but only during the first two weeks. No significant differences were observed for A, E, B3 and B12 between groups. Lycopene was the only carotenoid exhibiting a significant higher concentration in term than in preterm HM between weeks 1 and 4 post-partum. When compared at equivalent post-menstrual age, preterm milk was significantly higher for vitamins B1, B2, B3, B6 and B9 and lower levels of vitamins A, E, ß-carotene, ß-cryptoxanthin, lutein, zeaxanthin and lycopene compared to their term counterparts. These results suggest that preterm breastfed infants at term equivalent age may receive lower amounts of these micronutrients than breast-fed term neonates, possibly highlighting the need to supplement or fortify their nutritional intake with vitamins and carotenoids. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT #02052245.


Assuntos
Carotenoides/análise , Recém-Nascido Prematuro/crescimento & desenvolvimento , Leite Humano/química , Necessidades Nutricionais/fisiologia , Vitaminas/análise , Suplementos Nutricionais , Ingestão de Alimentos , Feminino , Alimentos Fortificados , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Masculino , Avaliação Nutricional , Estudos Prospectivos
15.
Bull Environ Contam Toxicol ; 105(2): 299-306, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32653945

RESUMO

Impacts on urban water resources are invariably caused by the development of urban centers and the occupation of the watershed. The release of untreated effluents and urban runoff are sources of metals in adjacent water bodies. It is therefore important to conduct studies on the occurrence of these trace elements in the environment and the risks posed to human health. The aim of the present study was to determine Cd, Pb, Cu, and Zn concentrations in water bodies located in the Bacanga and Cachorros watersheds and correlate the occurrence of these elements with physicochemical variables of the water (temperature, pH, dissolved oxygen, and electrical conductivity). The variables were determined at the collection site with the aid of a multiparameter kit. Heavy metal concentrations were determined using anodic stripping voltammetry. The results revealed that the streams were not contaminated with the metals analyzed. The only exception was copper in the Limoeiro and Murtura streams, both of which are located in the industrial complex.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Brasil , Cobre/análise , Humanos , Temperatura
16.
Diabetol Metab Syndr ; 12: 16, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082424

RESUMO

BACKGROUND: Metabolic syndrome (MS) is a complex disorder represented by a set of cardiovascular risk factors usually related to central fat deposition, insulin resistance, hypertension and dyslipidemia. It is associated with accelerated atherosclerosis in response to chronic inflammation and vascular endothelial dysfunction, increasing overall mortality. The objective to evaluate the short and long term effect of the comprehensive cardiac rehabilitation program and intensive lifestyle intervention in metabolic syndrome patients. METHODS: This is longitudinal interventional study. All patients underwent a 20-session cardiac rehabilitation program with aerobic and resisted exercises as well as an educational program for lifestyle changes and follow up 1 year. RESULTS: Forty seven patients participated in the present study, but only 28 concluded the follow up. 77.7% were females and the majority was older than 60 years (63.1%). After cardiac rehabilitation, the percentage of overweight (0.04) patients who controlled the SBP (0.04) increased, and obesity levels I and II were reduced, as well as a significant reduction in total cholesterol and triglycerides (0.01 and 0.05), all of these variables remained similar after 1 year of follow-up. After cardiac rehabilitation all participants were practicing the five factors of healthy lifestyle, and reduced to 73% after follow up. CONCLUSION: A comprehensive cardiac rehabilitation program and lifestyle change is an effective approach in the treatment of patients with MS mainly, it has positive short and long term effects on weight control, reducing total cholesterol and triglycerides.

17.
Food Res Int ; 127: 108733, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882090

RESUMO

The aroma profile and volatile composition of 8 samples of black ripe olives from Manzanilla and Hojiblanca cultivars were analyzed with the aim to characterize this type of table olive. The aroma of samples was described by a sensory panel using quantitative descriptive analysis (QDA), whereas the volatiles were analyzed by headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). Eleven odor descriptors (briny, sautéed mushroom, earthy/soil-like, oak barrel, nutty, artificial fruity/floral, natural fruity/floral, vinegary, alcohol, fishy/ocean-like, and cheesy) were evaluated, of which only one descriptor (briny) showed a significant difference between cultivars. A total of 74 volatile compounds were identified in the headspace of samples, of which 12 were identified as significant volatiles contributing to the discrimination between Manzanilla and Hojiblanca black ripe olives. Partial least squares (PLS) regression was able to predict one odor descriptor (nutty) with sufficient accuracy and allowed identifying the volatiles that highly contributed to three odor descriptors of black ripe olives (nutty, natural fruity/floral, and cheesy).


Assuntos
Odorantes/análise , Olea/química , Compostos Orgânicos Voláteis/química , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Microextração em Fase Sólida
18.
Food Res Int ; 125: 108568, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554036

RESUMO

The present study revealed the effects of each step of black ripe olive processing (preservation, darkening, packing + sterilization) and storage on the volatile composition of two olive cultivars (Manzanilla and Hojiblanca). The preservation step enriched the volatile profile of the olives, mainly in ethyl acetate, methyl acetate, and ethanol. The darkening step produced the total or partial elimination of 55-65% of the volatiles identified before this step. Around 70% of the volatiles in the final products corresponded to compounds that were formed or increased significantly as a result of the sterilization treatment at 121 °C. Although differences in the volatile compositions and contents between Manzanilla and Hojiblanca were found, the dominant volatiles in both cultivars were benzaldehyde, dimethyl sulfide and ethyl acetate. Storage for 8 months had little influence on their volatile profiles, although the stability of individual volatiles in Manzanilla was better than that in the Hojiblanca cultivar.


Assuntos
Acetatos/química , Benzaldeídos/química , Etanol/química , Manipulação de Alimentos/métodos , Olea , Sulfetos/química , Armazenamento de Alimentos/métodos , Tempo
19.
J Colloid Interface Sci ; 552: 464-475, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31151023

RESUMO

There has recently been renewed interest in understanding the physics of foam flow in permeable media. As for Newtonian flows in fractures, the heterogeneity of local apertures in natural fractures is expected to strongly impact the spatial distribution of foam flow. Although several experimental studies have been previously performed to study foam flow in fractured media, none of them has specifically addressed that impact for parallel flow in a realistic fracture geometry and its consequences for the foam's in situ shear viscosity and bubble morphologies. To do so, a comprehensive series of single-phase experiments have been performed by injecting pre-generated foams with six different qualities at a constant flow rate through a replica of a Vosges sandstone fracture of well-characterized aperture map. These measurements were compared to measurements obtained in a Hele-Shaw (i.e., smooth) fracture of identical hydraulic aperture. The results show that fracture wall roughness strongly increases the foam's apparent viscosity and shear rate. Moreover, foam bubbles traveling in regions of larger aperture exhibit larger velocity, size, a higher coarsening rate, and are subjected to a higher shear rate. This study also presents the first in situ measurement of foam bubbles velocities in fracture geometry, and provides hints towards measuring the in situ rheology of foam in a rough fracture from the velocity maps, for various imposed mean flow rates. These findings echo the necessity of considering fracture wall when predicting the pressure drop through the fracture and the effective viscosity, as well as in situ rheology, of the foam.

20.
Sci Total Environ ; 676: 834-839, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31056191

RESUMO

In Mediterranean countries the table olive industry produces a huge volume of wastewaters that are phytotoxic due to their high sodium content. Olives intended for Spanish-style green olives are currently debittered with NaOH that generates lyes and washing waters that cannot be used for agronomic purposes. In this study, the substitution of NaOH with KOH during the debittering of Manzanilla and Hojiblanca cultivars was assessed as well as the vacuum evaporation of the olive wastewaters to comply with fertilizer requirements. Typical lactic acid fermentation occurred in brines of olives treated with KOH and a final product with similar color and flavor characteristics to those treated with NaOH was achieved. However, lower texture was found in olives debittered with KOH than those with NaOH, using them at the same molar concentration. Furthermore, the lyes and washing waters from the KOH treatment were concentrated up to 10% of their initial volume and they complied with Spanish requirements to be considered as organo-mineral fertilizers (Corganic > 4%, K2O > 2%, Ntotal + K20 > 6%) although an external source of nitrogen would be needed. They also had a high content in phenolic compounds, particularly hydroxytyrosol. This research demonstrates that table olives can be processed with KOH and the generated waste streams could have potential applications in agriculture or being a source of bioactive substances.


Assuntos
Agricultura/métodos , Fertilizantes , Hidróxidos/química , Olea/química , Compostos de Potássio/química , Eliminação de Resíduos/métodos , Águas Residuárias/química , Fermentação
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