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1.
Environ Res ; 248: 118247, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38253198

ABSTRACT

A series of adsorbents (activated carbons, ACs) were synthesized by physical and chemical activation of olive stones (OS) and their textural and chemical characteristics determined by complementary techniques such as N2 and CO2 physisorption, pH of the point zero of charge (pHPZC), HRSEM or XPS. Samples with a wide range of physicochemical properties were obtained by fitting the activation procedure. The performance of these adsorbents in filters working under dynamic conditions was studied by determining the corresponding breakthrough curves for the ethylene removal. The physicochemical transformations of OS during activation were related with the adsorptive performance of derivative ACs. Results were compared to those obtained using commercial carbons, in particular ACs, carbon black or carbon fibers, in order to identify the properties of these materials on influencing the adsorptive performance. In general, ACs from OS perform better than the commercial samples, being also easily regenerated and properly used during consecutive adsorption cycles. CO2-activation showed to be the best synthesis option, leading to granular ACs with a suitable microporosity and surface chemistry. These results could favour the integration of this type of inexpensive materials on devices for the preservation of climacteric fruits, in a clear example of circular economy by reusing the agricultural residues.


Subject(s)
Carbon Dioxide , Charcoal , Charcoal/chemistry , Biomass , Adsorption , Food Industry , Ethylenes
2.
BioTech (Basel) ; 12(4)2023 Dec 02.
Article in English | MEDLINE | ID: mdl-38131677

ABSTRACT

Soil microbial fuel cells (SMFCs) are bioelectrical devices powered by the oxidation of organic and inorganic compounds due to microbial activity. Seven soils were randomly selected from Bergen Community College or areas nearby, located in the state of New Jersey, USA, were used to screen for the presence of electrogenic bacteria. SMFCs were incubated at 35-37 °C. Electricity generation and electrogenic bacteria were determined using an application developed for cellular phones. Of the seven samples, five generated electricity and enriched electrogenic bacteria. Average electrical output for the seven SMFCs was 155 microwatts with the start-up time ranging from 1 to 11 days. The highest output and electrogenic bacterial numbers were found with SMFC-B1 with 143 microwatts and 2.99 × 109 electrogenic bacteria after 15 days. Optimal electrical output and electrogenic bacterial numbers ranged from 1 to 21 days. Microbial DNA was extracted from the top and bottom of the anode of SMFC-B1 using the ZR Soil Microbe DNA MiniPrep Protocol followed by PCR amplification of 16S rRNA V3-V4 region. Next-generation sequencing of 16S rRNA genes generated an average of 58 k sequences. BLAST analysis of the anode bacterial community in SMFC-B1 demonstrated that the predominant bacterial phylum was Bacillota of the class Clostridia (50%). However, bacteria belonging to the phylum Pseudomonadota (15%) such as Magnetospirillum sp. and Methylocaldum gracile were also part of the predominant electrogenic bacterial community in the anode. Unidentified uncultured bacteria accounted for 35% of the predominant bacterial community. Bioelectrical devices such as MFCs provide sustainable and clean alternatives to future applications for electricity generation, waste treatment, and biosensors.

3.
Arch Osteoporos ; 18(1): 124, 2023 10 03.
Article in English | MEDLINE | ID: mdl-37789128

ABSTRACT

PURPOSE: Fracture Liaison Services programs reduce mortality and the risk of refracture and increase treatment and adherence rates. Greater coverage is an important priority for the future. The aim was to determine the characteristics of patients over 50 years old who suffered fractures and the effectiveness of a Fracture Liaison Services program in a health care institution in Colombia. METHODS: This was a retrospective follow-up study of a cohort of patients with vertebral and nonvertebral fractures managed in a Fracture Liaison Services program. Sociodemographic, clinical and pharmacological variables were identified. Key performance indicators were used to evaluate the effectiveness of the program. Descriptive and bivariate analysis was performed. RESULTS: A total of 438 patients were analyzed. The average age was 77.5 years, and 78.5% were women. Hip and vertebral fractures were the most common (25.3% and 24.9%, respectively). Vertebral fractures prevailed in men (33.0% vs 22.7%; p = 0.041) and those of the radius/ulna in women (20.3% vs 10.6%; p = 0.031). A total of 29.7% had experienced a previous fracture, and 16.7% had received antiosteoporosis drugs. A total of 63.5% of the cases were managed surgically. At discharge, 58.8% received prescriptions for calcium/vitamin D, and 50.7% with prescriptions of antiosteoporotic therapy, especially teriparatide (21.2%) and denosumab (16.4%), without significant differences by sex. However, in women with hip fractures, anti-osteoporotic management prevailed (83.7% vs 64.0; p = 0.032). The effectiveness of the overall program per year was 74.6%. On follow-up, only 9.1% of patients had experienced a new fall, and of those 3.7% presented a new fracture. A total of 4.3% died during follow-up. CONCLUSIONS: Good adherence to the recommendations of the country's clinical practice guidelines was found, and overall, the effectiveness of the program was very satisfactory, with a low incidence of new fractures during follow-up. Fracture Liaison Services programs reduce mortality and the risk of refracture. A retrospective follow-up study of a cohort of patients with vertebral and nonvertebral fractures managed in a Fracture Liaison Services, showed that the effectiveness was 73.6%. On follow-up, 9.1% of patients had experienced a new fall, and of those 3.7% presented a new fracture.


Subject(s)
Bone Density Conservation Agents , Osteoporotic Fractures , Spinal Fractures , Male , Humans , Female , Aged , Middle Aged , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/prevention & control , Bone Density Conservation Agents/therapeutic use , Colombia/epidemiology , Follow-Up Studies , Retrospective Studies , Spinal Fractures/epidemiology , Spinal Fractures/therapy
4.
Biomedica ; 43(1): 27-36, 2023 03 30.
Article in English, Spanish | MEDLINE | ID: mdl-37167471

ABSTRACT

Fungal sinusitis is a pathology that can occur in patients with diabetes mellitus and be associated with a hyperglycemic crisis. It is an aggressive entity with local complications that include involvement of the orbit or the central nervous system, and vascular involvement. Despite surgical and antifungal treatment, mortality raises up to 75%. We report the case of a female patient with a diagnosis of diabetic ketoacidosis and signs of unilateral ophthalmoplegia, which led to the study with magnetic resonance imaging of the central nervous system, finding signs of sinusitis, meningitis, and cerebritis. Initial microbiological studies were negative, and biomarkers such as serum galactomannan and Cryptococcus antigen were also negative. After surgical management and the identification of Aspergillus flavus and Rhizopus spp. in sinus tissue, the patient received treatment with posaconazole and after two months of follow-up she presented clinical improvement. Dual fungal infection and infection by A. flavus are uncommon and clinically relevant entities, with no cases previously reported in our country, therefore this corresponds to a case of clinical interest.


La sinusitis micótica es una condición patológica que puede presentarse en pacientes con diabetes mellitus y estar asociada a una crisis hiperglucémica. Es una entidad agresiva con complicaciones locales que incluyen afectación de la órbita y el sistema nervioso central, y compromiso vascular. A pesar del tratamiento quirúrgico y antimicótico, la mortalidad es de hasta el 75 %. Se describe el caso de una paciente con diagnóstico de cetoacidosis diabética y signos de oftalmoplejía unilateral que llevaron al estudio con resonancia magnética del sistema nervioso central; se encontraron signos de sinusitis, meningitis y cerebritis. Los estudios microbiológicos iniciales fueron negativos, y los biomarcadores galactomanano sérico y el antígeno de Cryptococcus también fueron negativos. Tras el manejo quirúrgico, se llegó a la identificación de Aspergillus flavus y Rhizopus spp. en el tejido de los senos paranasales. La paciente recibió tratamiento con posaconazol y, tras dos meses de seguimiento, había presentado mejoría clínica. La infección fúngica dual y la infección por A. flavus son entidades poco frecuentes y de relevancia clínica, sin casos presentados previamente en nuestro país por lo que este corresponde a un caso de interés clínico.


Subject(s)
Diabetes Mellitus , Rhizopus oryzae , Humans , Aspergillus flavus , Retrospective Studies
5.
Biomédica (Bogotá) ; 43(1): 27-36, mar. 2023. tab, graf
Article in Spanish | LILACS | ID: biblio-1533914

ABSTRACT

La sinusitis micótica es una condición patológica que puede presentarse en pacientes con diabetes mellitus y estar asociada a una crisis hiperglucémica. Es una entidad agresiva con complicaciones locales que incluyen afectación de la órbita y el sistema nervioso central, y compromiso vascular. A pesar del tratamiento quirúrgico y antimicótico, la mortalidad es de hasta el 75 %. Se describe el caso de una paciente con diagnóstico de cetoacidosis diabética y signos de oftalmoplejía unilateral que llevaron al estudio con resonancia magnética del sistema nervioso central; se encontraron signos de sinusitis, meningitis y cerebritis. Los estudios microbiológicos iniciales fueron negativos, y los biomarcadores galactomanano sérico y el antígeno de Cryptococcus también fueron negativos. Tras el manejo quirúrgico, se llegó a la identificación de Aspergillus flavus y Rhizopus spp. en el tejido de los senos paranasales. La paciente recibió tratamiento con posaconazol y, tras dos meses de seguimiento, había presentado mejoría clínica. La infección fúngica dual y la infección por A. flavus son entidades poco frecuentes y de relevancia clínica, sin casos presentados previamente en nuestro país por lo que este corresponde a un caso de interés clínico.


Fungal sinusitis is a pathology that can occur in patients with diabetes mellitus and be associated with a hyperglycemic crisis. It is an aggressive entity with local complications that include involvement of the orbit or the central nervous system, and vascular involvement. Despite surgical and antifungal treatment, mortality raises up to 75%. We report the case of a female patient with a diagnosis of diabetic ketoacidosis and signs of unilateral ophthalmoplegia, which led to the study with magnetic resonance imaging of the central nervous system, finding signs of sinusitis, meningitis, and cerebritis. Initial microbiological studies were negative, and biomarkers such as serum galactomannan and Cryptococcus antigen were also negative. After surgical management and the identification of Aspergillus flavus and Rhizopus spp. in sinus tissue, the patient received treatment with posaconazole and after two months of follow-up she presented clinical improvement. Dual fungal infection and infection by A. flavus are uncommon and clinically relevant entities, with no cases previously reported in our country, therefore this corresponds to a case of clinical interest.


Subject(s)
Aspergillus flavus , Diabetes Mellitus , Rhizopus oryzae , Aspergillosis , Sinusitis , Invasive Fungal Infections , Mucormycosis
6.
Antibiotics (Basel) ; 12(2)2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36830163

ABSTRACT

Antibiotics are frequently prescribed to patients with COVID-19. The aim was to determine the pattern of use of systemic antibiotics in a group of patients diagnosed with COVID-19 in Colombia between 2020-2022. This was a descriptive cross-sectional study designed to identify antibiotics prescription patterns for patients diagnosed with COVID-19 treated in eight clinics in Colombia. The AWaRe tool of the World Health Organization (WHO) was used to classify the antibiotics. A total of 10,916 patients were included. The median age was 57 years, and 56.4% were male. A total of 57.5% received antibiotics, especially ampicillin/sulbactam (58.8%) and clarithromycin (47.9%). Most of the antibiotics were classified as Watch (65.1%), followed by Access (32.6%) and Reserve (2.4%). Men (OR: 1.29; 95%CI: 1.17-1.43), older adults (OR: 1.67; 95%CI: 1.48-1.88), patients with dyspnea (OR: 1.26; 95%CI: 1.13-1.41), rheumatoid arthritis (OR: 1.94; 95%CI: 1.17-3.20), and high blood pressure at admission (OR: 1.45; 95%CI: 1.29-1.63), patients treated in-hospital (OR: 5.15; 95%CI: 4.59-5.77), patients admitted to the ICU (OR: 10.48; 95%CI: 8.82-12.45), patients treated with systemic glucocorticoids (OR: 3.60; 95%CI: 3.21-4.03) and vasopressors (OR: 2.10; 95%CI: 1.60-2.75), and patients who received invasive mechanical ventilation (OR: 2.37; 95%CI: 1.82-3.09) were more likely to receive a systemic antibiotic. Most of the patients diagnosed with COVID-19 received antibiotics, despite evidence showing that bacterial coinfection is rare. Antibiotics from the Watch group predominated, a practice that goes against WHO recommendations.

7.
Nanomaterials (Basel) ; 12(24)2022 Dec 13.
Article in English | MEDLINE | ID: mdl-36558291

ABSTRACT

Heterogeneous catalysts based on magnetite nanoparticles, Fe3O4, were prepared by the chemical coprecipitation method using iron (III) chloride as a salt precursor. The physicochemical properties of the nanoparticles were determined by different techniques and the efficiency was evaluated for the degradation of the cytostatic drug, 5-fluorouracil (5-FU), in aqueous solution by photo-Fenton process under simulated solar radiation. The most influential parameters, namely pH of the solution, catalyst load, H2O2 dosage, and use of radiation, were studied and optimized in the degradation process. The optimal conditions to achieve a 100% degradation of 5-FU (10 mg L-1) and a high mineralization degree (76%) were established at the acidic pH of 3.0, 100 mg L-1 of catalyst loading, and 58 mM of H2O2 under simulated solar radiation. The contribution of iron leaching to the catalyst deactivation, the role of the dissolved iron ions on homogenous reactions, and the stability of the catalyst were assessed during consecutive reaction cycles.

8.
J Psychopharmacol ; 36(10): 1161-1175, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36121009

ABSTRACT

BACKGROUND: Substance use disorder emerges in a small proportion of drug users and has the characteristics of a chronic relapsing pathology. AIMS: Our study aimed to demonstrate and characterize the variability in the expression of the rewarding effects of cocaine in the conditioned place preference (CPP) paradigm. METHODS: A cocaine-CPP paradigm in male Sprague-Dawley rats with an extinction period of 12 days and reinstatement was conducted. A statistical model was developed to distinguish rats expressing or not a cocaine-induced place preference. RESULTS: Two groups of rats were identified: rats that did express rewarding effects (CPP expression (CPPE), score >102 s) and rats that did not (no CPP expression (nCPPE), score between -85 and 59 s). These two groups did not show significant differences in a battery of behavioral tests. To identify differentially expressed genes in the CPPE and nCPPE groups, a whole-transcriptome ribonucleic acid-sequencing analysis was performed in the nucleus accumbens (NAc) 24 h after the CPP test. Four immediate early genes (Fos, Egr2, Nr4a1, and Zbtb37) were differentially expressed in the NAc of CPPE rats after expression of CPP. Variability in cocaine-induced place preference persisted in the CPPE and nCPPE groups after the extinction and reinstatement phases. Transcriptomic differences observed after reinstatement were distinct from those observed immediately after expression of CPP. CONCLUSION: These new findings provide insights into the identification of mechanisms underlying interindividual variability in the response to cocaine's rewarding effects.


Subject(s)
Cocaine , Animals , Cocaine/pharmacology , Extinction, Psychological , Individuality , Male , Nucleus Accumbens , RNA/metabolism , RNA/pharmacology , Rats , Rats, Sprague-Dawley , Transcriptome
9.
Life (Basel) ; 12(7)2022 Jul 13.
Article in English | MEDLINE | ID: mdl-35888130

ABSTRACT

Preterm neonates are at high risk of infectious and inflammatory diseases which require antibiotic treatment. Antibiotics influence neonatal gut microbiome development, and intestinal dysbiosis has been associated with delayed gastrointestinal transit. Neonates who take less time to pass meconium have a better tolerance to enteral feeding. We analyzed the effect of neonatal antibiotic treatment on the stool pattern and oral tolerance in 106 preterm infants < 33 weeks gestational age. Neonates were classified in 3 groups according to neonatal antibiotic (ABT) treatment days: no antibiotics, 3−7 d ABT, and ≥8 d ABT. Preterm infants from the ≥8 d ABT group took longer to pass meconium and to start green and yellow stools, took longer to reach 100 and 150 mL/kg/day, and reached reduced volumes in enteral feeds at day of life 14 and 28 than infants from no ABT and 3−7 d ABT groups. Multiple linear regression models showed that neonatal antibiotic treatment, birth weight, invasive mechanical ventilation, surfactant, enteral feeding start day, neonatal parenteral nutrition, and neonatal fasting days are associated with the stool pattern and oral tolerance in preterm infants.

10.
Drugs Real World Outcomes ; 9(3): 487-501, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35819624

ABSTRACT

BACKGROUND: Analgesics provide multiple clinical benefits but they are not without risks. OBJECTIVE: The aim of this study was to compare the outpatient prescribing pattern of analgesics between cities and municipalities in Colombia and to identify the variables associated with prescribing opioid analgesics. METHODS: This was a cross-sectional study that identified the prescription of analgesics for outpatient use from a population database of 8.5 million Colombians. A descriptive, bivariate, and multivariate analysis was performed. RESULTS: A total of 573,248 patients were identified who had received prescriptions for an analgesic. Mean age was 46.5 ± 23.6 years and 65.7% were females. The most commonly prescribed analgesics were non-opioid analgesics, antispasmodics, and opioid analgesics. The average milligram equivalent of morphine was higher in capital cities than in municipalities. Age ≥ 65 years (odds ratio [OR] 2.60, 95% confidence interval [CI] 2.54-2.67), male sex (OR 1.09, 95% CI 1.07-1.11), dispensing in cities (OR 2.25, 95% CI 2.20-2.30) and experiencing chronic pain (OR 13.25, 95% CI 10.89-16.14) were associated with an increased risk of receiving an opioid analgesic. CONCLUSIONS: Differences were found in the prescription of analgesics between capital cities and municipalities. The use of opioids does not appear to be in line with the recommendations for clinical practice, and they were mainly prescribed for elderly males with chronic non-oncological pain and for residents of capital cities.

11.
Acta méd. colomb ; 47(2): 43-46, Apr.-June 2022. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1419924

ABSTRACT

Abstract A patient with chronic brainstem CVA sequelae received one cycle of magnetic stimulation to treat her dysphagia and serendipitously obtained a minimal improvement in her axial movement. Two additional cycles gave her improved postural control and then distal movement, preceded by a display of ipsilateral and contralateral motor evoked potentials, respectively. Magnetic stimulation at 10 Hertz produces cortical disinhibition and reopens the critical neurodevelop ment periods. The ontogenic pattern of hemiplegia recovery in this patient may be explained by an increased and rejuvenated brain plasticity due to critical period reopening through cortical disinhibition. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2253).


Resumen Una paciente con secuelas crónicas de un ACV del tallo cerebral recibió un ciclo de estimulación magnética para el manejo de la disfagia y, por serendipia obtuvo mejoría leve del movimiento axial. Dos ciclos adicionales le permitieron mejoría del control postural y luego la aparición de movimiento distal, precedidos por la visualización de los potenciales evocados motores ipsilateral y contralateral, respectivamente. La estimulación magnética a 10 Hertz produce desinhibición cortical y reabre los periodos críticos del neurodesarrollo. Es posible, que el patrón ontogénico de recuperación de la hemiplejía en esta paciente se explique por el incremento y rejuvenecimiento de la plasticidad cerebral debido a la reapertura de los periodos críticos, por medio de la desinhibición cortical. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2253).

12.
Nanomaterials (Basel) ; 12(3)2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35159683

ABSTRACT

Graphitic carbon nitride (g-C3N4) was used to enhance the photocatalytic activity of ZnO nanoparticles for the degradation of 5-fluorouracil (5-FU) cytostatic drug under UV-LED irradiation. CN/ZnO composites were synthetized by an easy one-pot thermal method, varying the g-C3N4 loading, i.e., from 10 to 67 wt% and a post-thermal exfoliation in air. The physicochemical and optical properties of the materials were analyzed by several techniques. CN/ZnO composites showed a coral-like structure of spherical ZnO wurtzite particles on the g-C3N4 structure. In general, the synergism and heterojunction interface between both phases allowed the enhancement of the mesoporosity, light absorption ability, and the aromaticity of the corresponding composites. Moreover, the photocatalytic activity of the CN/ZnO composites was increased with the addition of g-C3N4 in comparison with pristine ZnO. The highest activity was found for the composite containing 25 wt% of g-C3N4 (i.e., CN25/ZnO), reaching the total degradation of 5-FU and a mineralization of 48% at 180 min, as well as a good photostability during four reuse cycles. Experiments with different pH solutions and scavengers allowed for the assessment of the reactive oxygen species (ROS) involved in the 5-FU degradation pathway, with radicals and non-radical species as the main responsible active species. Furthermore, a tentative photocatalytic mechanism was proposed for CN/ZnO composites.

13.
Salud bienestar colect ; 5(3): 129-146, dic. 2021.
Article in Spanish | LILACS | ID: biblio-1399895

ABSTRACT

Abordar en este ensayo relatos de migración, exigió una mirada fenoménica existencial-genero-sensitiva; en torno a lo vivido y experienciado por 05 mujeres venezolanas que migraron a Ecuador. Propósito. Visibilizar las razones que las obligaron a emigrar, estrategias de sobrevivencia en los nuevos hogares transnacionales. Evidenciar que hay detrás de la feminizacion de la migración y la situación de salud de las migrantes. En qué dimensión el acceso a los servicios de salud afecta la salud de las mujeres migrantes. Lo metódico: Paradigma cualitativo enfoque fenomenológico-existencial. Análisis de discurso. La técnica dialógica para la recolección de información fue la entrevista focalizada. Se realizaron 10 grabaciones en total. Se utilizó consentimiento informado. Las entrevistas fueron sometidas a su respectivo itinerario metodológico. Aproximaciones: Las razones de migrar: huir de la situación económica, política y social que vive Venezuela. Se repiten los roles y estereotipos de género. Ubicación de las mujeres en las cadenas globales del cuidado, oficios del hogar. El acceso a los servicios de salud es un proceso lento, burocrático y sin resolución. El modelo Bio-Medico en la relación médico-paciente estuvo marcado por la Indiferencia, exclusión, ejercicio del poder. Clara violación al Derecho a la Salud y los Derechos Humanos.


Addressing in this essay stories of migration, demanded an existential-gender-sensitive phenomenal look at what was experienced and experienced by 05 Venezuelan women who migrated to Ecuador. Purpose. To make visible the reasons that forced them to emigrate, survival strategies in the new transnational homes. To show that there is behind Addressing in this essay stories of migration, demanded an existential-gender-sensitive phenomenal look at what was experienced and experienced by 05 Venezuelan women who migrated to Ecuador. Purpose. To make visible the reasons that forced them to emigrate, survival strategies in the new transnational homes. To show that there is behind the feminization of migration and the health situation of migrants. The extent to which access to health services affects the health of migrant women. The methodical: Qualitative paradigm phenomenological-existential approach. Discourse analysis. The dialogic technique for collecting information was the focused interview. A total of 10 recordings were made. Informed consent was used. The interviews were submitted to their respective methodological itinerary. Approaches: The reasons for migrating: fleeing the economic, political and social situation in Venezuela. The roles are repeated and the feminization of migration and the health situation of migrants. The extent to which access to health services affects the health of migrant women. The Bio-Medical model in the doctor-patient relationship, was marked by indifference, exclusion, exercise of power. Clear violation of the right to health and human rights.


Subject(s)
Humans , Female , Adult , Middle Aged , Aged , Health , Human Migration/statistics & numerical data , Venezuela , Interview , Ecuador , Evaluation Studies as Topic , Gender Identity , Informed Consent , Life Change Events
14.
Heliyon ; 7(10): e08150, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34746459

ABSTRACT

The aim of this study was to investigate how social responsibility marketing campaigns can be effective in branding for young millennials. An empirical model was applied in three specific cases of cause marketing targeting Generation Y. A total sample of 547 young people was obtained, and the data were analysed through the structural equation methodology using PLS data technical analysis. The results showed that, for millennials, marketing actions with a cause are effective in positioning the brands that carry them out favourably as long as requirements such as the alignment of their objectives with the social ideals and their closeness to millennials are met. Likewise, all the communication elements of the message will influence its effectiveness. This study provides new evidence on the attitudes of young millennials towards brands' social marketing actions.

15.
Sensors (Basel) ; 21(15)2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34372338

ABSTRACT

Motor imagery (MI) promotes motor learning and encourages brain-computer interface systems that entail electroencephalogram (EEG) decoding. However, a long period of training is required to master brain rhythms' self-regulation, resulting in users with MI inefficiency. We introduce a parameter-based approach of cross-subject transfer-learning to improve the performances of poor-performing individuals in MI-based BCI systems, pooling data from labeled EEG measurements and psychological questionnaires via kernel-embedding. To this end, a Deep and Wide neural network for MI classification is implemented to pre-train the network from the source domain. Then, the parameter layers are transferred to initialize the target network within a fine-tuning procedure to recompute the Multilayer Perceptron-based accuracy. To perform data-fusion combining categorical features with the real-valued features, we implement stepwise kernel-matching via Gaussian-embedding. Finally, the paired source-target sets are selected for evaluation purposes according to the inefficiency-based clustering by subjects to consider their influence on BCI motor skills, exploring two choosing strategies of the best-performing subjects (source space): single-subject and multiple-subjects. Validation results achieved for discriminant MI tasks demonstrate that the introduced Deep and Wide neural network presents competitive performance of accuracy even after the inclusion of questionnaire data.


Subject(s)
Brain-Computer Interfaces , Imagination , Electroencephalography , Humans , Machine Learning , Surveys and Questionnaires
16.
Sensors (Basel) ; 21(13)2021 Jun 29.
Article in English | MEDLINE | ID: mdl-34209582

ABSTRACT

Motion capture (Mocap) data are widely used as time series to study human movement. Indeed, animation movies, video games, and biomechanical systems for rehabilitation are significant applications related to Mocap data. However, classifying multi-channel time series from Mocap requires coding the intrinsic dependencies (even nonlinear relationships) between human body joints. Furthermore, the same human action may have variations because the individual alters their movement and therefore the inter/intraclass variability. Here, we introduce an enhanced Hilbert embedding-based approach from a cross-covariance operator, termed EHECCO, to map the input Mocap time series to a tensor space built from both 3D skeletal joints and a principal component analysis-based projection. Obtained results demonstrate how EHECCO represents and discriminates joint probability distributions as kernel-based evaluation of input time series within a tensor reproducing kernel Hilbert space (RKHS). Our approach achieves competitive classification results for style/subject and action recognition tasks on well-known publicly available databases. Moreover, EHECCO favors the interpretation of relevant anthropometric variables correlated with players' expertise and acted movement on a Tennis-Mocap database (also publicly available with this work). Thereby, our EHECCO-based framework provides a unified representation (through the tensor RKHS) of the Mocap time series to compute linear correlations between a coded metric from joint distributions and player properties, i.e., age, body measurements, and sport movement (action class).


Subject(s)
Algorithms , Movement , Humans , Motion , Principal Component Analysis
17.
Environ Monit Assess ; 193(8): 467, 2021 Jul 05.
Article in English | MEDLINE | ID: mdl-34224011

ABSTRACT

The equilibrium and kinetic studies of removal of Pb2+, Cd2+, Ni2+, and Cu2+ metal ions were carried out using activated carbon prepared from palm kernel shell and doped with CeO2 (Ce/AC). The obtained material carbon was characterized by XRD which showed some crystalline traces of CeO2, SEM displaying the porous texture with spherical pores and the determination of pH of point of zero charge (pHPZC) which was found to be equal to 6. The contact time and adsorbate were thoroughly investigated. The maximum adsorption depends inversely on the hydrated metal radius. This observation was confirmed by calculating the formation energies (ΔH(M(OH)2)) of M(OH)2. The metal ionic radii were acting on calculated sorption capacity and that sorption efficiency related to ionic radii of metal was as follows: R(Ni2+) ≤ R(Cd2+) < R(Cu2+) < R(Pb2+). The texture and morphology of the material after sorption were affected by the metallic ion nature as observed by SEM. The kinetic studies showed that the rate constant (k2) of pseudo-second-order model decreased with the increase of the hydrated cations radii, while the rate constant of intraparticle diffusion increased with the increase of the ionic radii. The Freundlich isotherm model best fit the experimental sorption data for all the metallic ions.


Subject(s)
Trace Elements , Water Pollutants, Chemical , Adsorption , Cadmium/analysis , Cerium , Charcoal , Environmental Monitoring , Hydrogen-Ion Concentration , Kinetics , Lead , Water Pollutants, Chemical/analysis
18.
Nanomaterials (Basel) ; 11(6)2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34203965

ABSTRACT

Graphene oxide (GO) is used to enhance the photocatalytic activity of ZnO nanoparticles for the degradation of vanillic acid (VA) under simulated solar light and visible-LED (λ > 430 nm). ZnO-GO composites are prepared by a mixing and sonication process with different GO loadings (i.e., from 1.8 to 6.5 wt.%). The materials are extensively characterized by thermogravimetric analysis (TGA), physisorption of N2, X-ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM), point of zero charge (pHPZC), and UV-Vis diffuse reflectance spectroscopy (DRUV). The presence of GO increases the photocatalytic activity of all the prepared composites in comparison with the pristine ZnO. The highest photocatalytic activity is found for the composite containing 5.5 wt.% of GO (i.e., ZnO-GO5.5), reaching a VA degradation of 99% and 35% under solar light and visible-LED, respectively. Higher TOC removal/VA degradation ratios are obtained from the experiments carried out under visible-LED, indicating a more effective process for the mineralization of VA than those observed under simulated solar light. The influence of hole, radical, and non-radical scavengers is studied in order to assess the occurrence of the reactive oxygen species (ROS) involved in the photocatalytic mechanism. The study of the photo-stability during three reuse experiments indicates that the presence of GO in the composites reduces the photocorrosion in comparison with pristine ZnO.

19.
Molecules ; 26(10)2021 May 18.
Article in English | MEDLINE | ID: mdl-34069848

ABSTRACT

Escherichia coli colonies were grown on different supports for the removal of nitrates from water. A carbon material and different commercial metal oxides, such as SiO2, TiO2 and Al2O3, and their corresponding carbon-metal oxide composites were studied. The physicochemical properties were analyzed by different techniques and the results were correlated with their performance in the denitrification process. Developed biofilms effectively adhere to the supports and always reach the complete reduction of nitrates to gaseous products. Nevertheless, faster processes occur when the biofilm is supported on mesoporous and non-acid materials (carbon and silica).


Subject(s)
Agriculture , Biofilms , Carbon/pharmacology , Nitrates/isolation & purification , Oxides/pharmacology , Wastewater/chemistry , Water Purification , Biofilms/drug effects , Carbon/toxicity , Denitrification , Escherichia coli/growth & development , Escherichia coli/physiology , Escherichia coli/ultrastructure , Hydrogen-Ion Concentration , Oxides/toxicity , Particle Size , Thermogravimetry , X-Ray Diffraction
20.
J Gynecol Obstet Hum Reprod ; 50(1): 101827, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32512213

ABSTRACT

INTRODUCTION: Several algorithms for first-trimester screening for preeclampsia are available; however, the Gaussian model algorithm is more likely to match the characteristics of different populations. It is recommended to validate a screening strategy before being implemented in clinical practice; unfortunately, the validation process might not be feasible in all settings. Thus, the aim of this study was to provide cut-off values for the Gaussian model for its use in clinical practice. MATERIAL AND METHODS: This prospective cohort study was conducted at Vall d'Hebron University Hospital (Barcelona) from October 2015 to September 2017. A total of 2641 women with singleton pregnancies were recruited. Recorded at the first-trimester scan were demographic characteristics, maternal obstetric history, maternal history, uterine artery Doppler and arterial blood pressure. Serum concentrations of pregnancy-associated plasma protein-A and placental growth factor were assessed from the first-trimester blood test. Detection rates and cut-off values for fixed 5%, 10 %, 15 %, 20 %, 25 % and 30 % false-positive rates were calculated for all combinations of markers. RESULTS: Ninety (3.41 %) of the 2641 women developed preeclampsia, which was early-onset in 11 (0.42 %). The cut-off values and their respective detection rates, for the screening of early-onset PE by all possible combinations of markers involved in this model, are provided. DISCUSSION: When external validation of first-trimester screening for preeclampsia before its clinical implementation is not feasible, the cut-off values from the Gaussian model algorithm provided in this study could be used and median values corrected prospectively if necessary.


Subject(s)
Early Diagnosis , Pre-Eclampsia/diagnosis , Adult , Algorithms , Biomarkers/blood , Cohort Studies , Female , Humans , Placenta Growth Factor/blood , Pregnancy , Pregnancy Trimester, First , Pregnancy-Associated Plasma Protein-A/analysis , Pulsatile Flow , Ultrasonography, Doppler , Uterine Artery/diagnostic imaging
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