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1.
J Fluoresc ; 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37987984

RESUMEN

Fe3O4@Y2O3:Eu3+ nanocomposites and Y2O3:Eu3+ nanophosphors were synthesized using the hydrothermal method. Nanocomposites were analyzed using X-ray diffraction (XRD), Rietveld refinements, Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, photoluminescence (PL), vibrating sample magnetometer (VSM), and high-resolution transmission electron microscopy (HRTEM). Nanocomposites exhibit superparamagnetic behavior that improves with Eu3+, resulting in increased magnetic saturation. In contrast to Y2O3:Eu3+ nanophosphors, the Fe3O4@Y2O3:Eu3+ nanocomposites display a distinctive characteristic whereby the photoluminescence intensity increases with a reduced concentration of Eu3+. The requirement of increasing the thickness of the Y2O3:Eu3+ outer layer to achieve improved light emission can be circumvented by solely manipulating the concentration of activators, without compromising the magnetic saturation of the nanocomposites. The luminescent and magnetic characteristics of Fe3O4@Y2O3:Eu3+ nanocomposites can be readily optimized using straightforward synthesis parameters, making them promising candidates for potential applications in theranostic medicine.

2.
Rev Med Chil ; 149(12): 1723-1736, 2021 Dec.
Artículo en Español | MEDLINE | ID: mdl-35735340

RESUMEN

BACKGROUND: Quarantines may exacerbate the presence of emotional symptoms or anxiety. AIM: To explore the relation between time spent in lockdown and development of depressive and anxiety symptoms. MATERIAL AND METHODS: A survey including the GAD anxiety and PHQ-9 depression scores was answered online by 1,488 subjects aged 36 ± 14 years (74% women), invited to participate through social networks. Both scores are validated for the Chilean population. RESULTS: Most responders had a private health insurance system. Sixty seven percent had clinically significant depressive symptoms and 39% had anxiety symptoms. Spending four or more weeks of lockdown (quarantine) was associated with 1.6 times higher risk of developing depressive symptoms and 2.9 times higher risk of developing anxiety symptoms. Difficulties in access to health care increased 3.3 times the risk of developing depression. Suffering a respiratory disease increased 2.39 times the risk of developing anxiety. CONCLUSIONS: There was a direct association between depressive and anxious symptoms, and the time spent of quarantine.


Asunto(s)
Depresión , Cuarentena , Ansiedad/epidemiología , Trastornos de Ansiedad , Depresión/epidemiología , Depresión/etiología , Depresión/psicología , Femenino , Humanos , Masculino , Cuestionario de Salud del Paciente , Cuarentena/psicología
3.
Med Teach ; 42(9): 1051-1057, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32697116

RESUMEN

BACKGROUND: Medical curricula have historically been designed in a top-down approach, usually excluding students. While Delphi panels have been used as a tool for medical education curricula design, none have been conducted in Ecuador. In addition, no such approach has ever included students both as panelists and researchers. MATERIAL AND METHODS: Four Delphi panels were developed and conducted using a participatory approach that allowed medical students to take part both as expert panelists and researchers: specifically, students developed the questionnaire and conducted a qualitative synthesis. Questionnaire responses were anonymized and dispatched online to panelists. The information was organized and collected to develop the qualitative syntheses and prepare the final statements. RESULTS: Thirty-two medical students participated between February and May 2018. A total of 32 questions were developed, corresponding to five different categories. For some questions, consensus was reached; for other questions, general statements were obtained.Discussion and conclusion: Developing the questionnaire, responding to it and analyzing the answers allowed students to raise significant concerns regarding medical education topics proposing relevant policy and curricula change. Participatory Delphi panels can be an efficient tool to obtain organized feedback, improve student class involvement, and promote research skills.


Asunto(s)
Educación de Pregrado en Medicina , Educación Médica , Estudiantes de Medicina , Curriculum , Técnica Delphi , Ecuador , Humanos
4.
Phys Rev Lett ; 120(24): 243002, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29957009

RESUMEN

We show that a system of three species of one-dimensional fermions, with an attractive three-body contact interaction, features a scale anomaly directly related to the anomaly of two-dimensional fermions with two-body contact forces. We show, furthermore, that those two cases (and their multispecies generalizations) are the only nonrelativistic systems with contact interactions that display a scale anomaly. While the two-dimensional case is well known and has been under study both experimentally and theoretically for years, the one-dimensional case presented here has remained unexplored. For the latter, we calculate the impact of the anomaly on the equation of state, which appears through the generalization of Tan's contact for three-body forces, and determine the pressure at finite temperature. In addition, we show that the third-order virial coefficient is proportional to the second-order coefficient of the two-dimensional two-body case.

6.
Int Nurs Rev ; 62(3): 303-11, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25645450

RESUMEN

BACKGROUND: As future health educators, nursing and physiotherapy students will play an essential role in the prevention of smoking. AIM: To determine the prevalence of smoking among students and to analyse their knowledge of and attitudes towards smoking. METHOD: This was a descriptive cross-sectional study using an anonymous questionnaire and conducted in a Spanish Faculty of Health Sciences in 2013. FINDINGS: 247 nursing and physiotherapy students (82.33%) participated in the study. The global prevalence of smoking (18.2%) was lower compare with the general population group of the same age. We have observed statistical significance in relation to previous studies. Nursing and physiotherapy students showed a low nicotine dependence. We found a lack of knowledge about the harmful effects of cigarette consumption on health. Statistically significant results were also found in relation to degree courses (p < 0.01) as regards students' opinions about their knowledge of strategies and methods to help patients stop smoking. CONCLUSION: Most students started smoking before commencing their university studies; consequently, interventions should focus on cessation programmes. An analysis of university curricula leading to the award of a degree in the health sciences could serve to identify educational deficiencies in order to implement the necessary modifications. IMPLICATIONS FOR NURSING AND HEALTH POLICY: This paper presents an update in tobacco use characteristics amongst nursing and physiotherapy students. Those results have showed a need to improve the curricula in order to develop specific programmes to improve knowledge, attitudes and beliefs. Measures to prevent smoking must be taken at school.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Especialidad de Fisioterapia/educación , Fumar/epidemiología , Estudiantes del Área de la Salud/psicología , Estudiantes de Enfermería/psicología , Adulto , Estudios Transversales , Bachillerato en Enfermería , Femenino , Humanos , Masculino , Prevalencia , España/epidemiología , Encuestas y Cuestionarios
7.
Public Health Action ; 14(2): 76-81, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38957503

RESUMEN

OBJECTIVE: To identify individual-level early warning indicators of virologic failure in HIV patients receiving antiretroviral therapy (ART) in South Africa. DESIGN: A matched case-control study of individuals with and without virologic failure (VF) (>5 months on ART and HIV-1 plasma viral load >1,000 copies/mL) was conducted between June 2014 and June 2018. Of the 1,000 participants enrolled in the parent cohort, 96 experienced VF, and 199 additional controls were identified from the parent cohort and matched 1:2 (some matched 1:3) for sex, age, ART duration, and site. Participants were interviewed while clinical, pharmacy refill, laboratory, and objective pharmacological data were obtained. Multivariate conditional logistic regression models were constructed using model selection to identify factors associated with VF. Significant determinants of VF were identified using an alpha level of 0.05. RESULTS: In a full conditional model, higher cumulative ART adherence, quantified using tenofovir-diphosphate concentrations in dried blood spots (OR 0.26) and medication possession ratio (OR 0.98) were protective against VF, whereas an increase in total depression score (OR 1.20) was predictive of VF. CONCLUSION: This analysis demonstrates the importance of depression as a key individual-level early warning indicator of VF. Efforts to address mental health concerns among patients with people living with HIV could improve virologic suppression.


OBJECTIF: Identifier les indicateurs d'alerte précoce au niveau individuel de l'échec virologique chez les patients séropositifs recevant un traitement antirétroviral (TAR) en Afrique du Sud. MÉTHODE: Une étude cas-témoins appariée de personnes avec et sans échec virologique (FV, pour l'anglais « virologic failure ¼) (>5 mois sous ART et charge virale plasmatique du VIH-1 >1 000 copies/ml) a été menée entre juin 2014 et juin 2018. Sur les 1 000 participants inscrits dans la cohorte parente, 96 ont présenté une FV et 199 témoins supplémentaires ont été identifiés dans la cohorte parentale et appariés 1:2 (certains appariés 1:3) pour le sexe, l'âge, la durée du TAR et le site. Les participants ont été interrogés pendant que des données cliniques, de renouvellement de pharmacie, de laboratoire et pharmacologiques objectives ont été obtenues. Des modèles de régression logistique conditionnelle multivariée ont été construits à l'aide d'une sélection de modèles pour identifier les facteurs associés à la FV. Les déterminants significatifs de la FV ont été identifiés à l'aide d'un niveau alpha de 0,05. RÉSULTATS: Dans un modèle conditionnel complet, une observance cumulative plus élevée du TAR, quantifiée à l'aide des concentrations de ténofovir-diphosphate dans les gouttes de sang séché (OR 0,26) et du ratio de possession de médicaments (OR 0,98) protégeait contre la FV, tandis qu'une augmentation du score de dépression totale (OR 1,20) était prédictive de la FV. CONCLUSION: Cette analyse démontre l'importance de la dépression en tant qu'indicateur précoce clé au niveau individuel de la FV. Les efforts visant à résoudre les problèmes de santé mentale chez les personnes vivant avec le VIH pourraient améliorer la suppression virologique.

8.
Rev Clin Esp (Barc) ; 224(7): 457-465, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38879004

RESUMEN

BACKGROUND: Anemia is a common comorbidity in patients with diabetes mellitus (DM), particularly in older adults. However, there is a lack of data on the prevalence and the characteristics of anemia in this population in Spain. OBJECTIVE: To describe the prevalence and the characteristics of anemia in patients with DM aged 50 or older (PDM50) in a healthcare district in the province of Cádiz. METHODS: A retrospective cross-sectional study was conducted that included outpatient's laboratory tests (OLT) performed over 30 months at PDM50. RESULTS: The prevalence of anemia was 29.9% (95% CI: 28.7%-31.1%), predominating in women (33.3% vs 26.7%; P < 0.01), in older people stratified by decades (61.7% in 9th decade vs 12% in 5th decade; P < 0.01), and in those with kidney disease (44.7% vs 28%; P < 0.01). Most cases were mild (68.3%), normocytic (78.7%), and hypochromic (52%). Similarly, moderate-to-severe anemia was more frequent in women (39% vs 23%), their prevalence increased with age (45% in the 9th decade vs 24% in the 5th decade), and with the progression of kidney damage, either measured by a decreased glomerular filtration rate (GFR) (49% in G4 vs 25% in G1), or the presence of albuminuria (P < 0.01). No association was found between DM control, based on glycated hemoglobin (HbA1c), and anemia in either sex (P = 0.887). CONCLUSION: This study describes a high prevalence of anemia in PDM50, particularly in women, in the most advantageous people and in the presence of kidney disease, even in early stages, highlighting the clinical importance of this coexistence.


Asunto(s)
Anemia , Humanos , Femenino , Masculino , Anemia/epidemiología , Prevalencia , España/epidemiología , Estudios Transversales , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Diabetes Mellitus/epidemiología , Complicaciones de la Diabetes/epidemiología
9.
Semergen ; 46(3): 186-193, 2020 Apr.
Artículo en Español | MEDLINE | ID: mdl-31901403

RESUMEN

INTRODUCTION: Death is part of life. The awareness that death is inevitable could be the cause of mental disorders. OBJECTIVE: To determine the level of death anxiety in old people as regards age, gender, social aspects, physical and leisure activities, self-esteem, religion or advanced disease, as well as their preferences on the place where they want to die. MATERIAL AND METHOD: Cross-sectional observational study. Face-to-face interviews and Death Anxiety Scale (DAS) of Templer on 300 patients over 75years-old without a diagnosis of dementia, selected randomly in four health centres. RESULTS: A total of 288 surveys were completed. The mean age was 84.8 (15.2) years, and 147 (51.0%) were older than 85years. The score of medium-high anxiety observed in the DAS was higher in women (50%-39.6%; P=.030), in those who did not perform physical activity (68%-26.4%; P<.001), in those who did not take part in leisure activities (63.5%-41.7%; P=.007), in patients with depressed mood (60.4%-41.6%; P<.008), and in patients without advanced disease (48.3%-3 5.8%; P=.036). The fear of having a painful death was present in 255 (88.5%). Physical activity reduced the risk of medium-high anxiety by 5.3 times (OR=.188, P<.001), and screening positive for depression increased it by 2.9 times (OR=2.943, P=.014). As regards the place where they would prefer to die, 177 (61.5%) answered «at home¼, and 28 (9.7%) «in the hospital.¼ CONCLUSIONS: Older people do fear a painful death, but they are not really afraid of dying. Male gender and performing physical or leisure activities is related to low levels of death anxiety. Advanced disease leads to greater acceptance of the end of life. The desire to die at home, and to «dehospitalise¼ the death prevails.


Asunto(s)
Ansiedad , Miedo , Anciano de 80 o más Años , Actitud Frente a la Muerte , Estudios Transversales , Femenino , Hospitales , Humanos , Masculino , Encuestas y Cuestionarios
10.
Eur J Neurol ; 16(1): 127-33, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19049507

RESUMEN

BACKGROUND AND PURPOSE: Statins have shown some protective effect after ischaemic stroke in observational studies. However, this effect has never been assessed by etiological subtypes. METHODS: Observational study using data from the Stroke Unit Data Bank from consecutive patients with cerebral infarction. Variables analyzed: demographic data, cardiovascular risk factors, treatment with statins at stroke onset, stroke severity, stroke subtype, in-hospital complications, length of stay, and functional status at discharge (modified Rankin Scale). RESULTS: A total of 2742 patients were included, 1539 were men. Mean age was 69.17 years (SD 12.19). Of these, 281 patients (10.2%) were receiving statins when admitted. The logistic regression analyses showed that previous treatment with statins was an independent predictor for better outcome at discharge among all strokes (OR, 2.08; 95% CI, 1.39 to 3.1) as well as for the atherothrombotic (OR, 2.79; 95% CI, 1.33 to 5.84) and lacunar strokes (OR, 2.28; 95% CI, 1.15 to 4.52) after adjustment for demographic data, risk factors, previous treatments, stroke subtypes, stroke severity, in-hospital complications and length of stay. This benefit was not observed either in cardioembolic or in other etiology strokes. CONCLUSIONS: Previous treatment with statins is an independent factor associated with good outcomes in patients with ischaemic stroke. Atherothrombotic and small vessel strokes show the greatest benefit.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Trombosis Intracraneal/tratamiento farmacológico , Accidente Vascular Cerebral Lacunar/tratamiento farmacológico , Accidente Cerebrovascular/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/epidemiología , Estudios de Cohortes , Femenino , Humanos , Arteriosclerosis Intracraneal/tratamiento farmacológico , Arteriosclerosis Intracraneal/epidemiología , Trombosis Intracraneal/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Accidente Cerebrovascular/clasificación , Accidente Cerebrovascular/epidemiología , Accidente Vascular Cerebral Lacunar/epidemiología , Resultado del Tratamiento
11.
Poult Sci ; 88(5): 943-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19359681

RESUMEN

Sodium butyrate is a sodium salt of a volatile short-chain fatty acid (butyric acid) used to prevent Salmonella Enteritidis infection in birds. Three groups of fifty 1-d-old broilers each were fed the following diets: T0 = standard broiler diet (control); T1 = standard broiler diet supplemented with 0.92 g/kg of an additive with free sodium butyrate (Gustor XXI B92); and T2 = standard broiler diet supplemented with 0.92 g/kg of an additive with sodium butyrate partially protected with vegetable fats (Gustor XXI BP70). Twenty percent of the birds were orally infected with Salmonella Enteritidis at d 5 posthatching and fecal Salmonella shedding was assessed at d 6, 9, 13, 20, 27, 34, and 41 of the trial. At d 42, all birds were slaughtered and 20 of them dissected: crop, cecum, liver, and spleen were sampled for bacteriological analyses. Both butyrate-based additives showed a significant reduction (P < 0.05) of Salmonella Enteritidis infection in birds from d 27 onward. However, the partially protected butyrate additive was more effective at the late phase of infection. Partially protected butyrate treatment successfully decreased infection not only in the crop and cecum but also in the liver. There were no differences in the spleen. These results suggest that sodium butyrate partially protected with vegetable fats offers a unique balance of free and protected active substances effective all along the gastrointestinal tract because it is slowly released during digestion.


Asunto(s)
Butiratos/farmacología , Pollos , Suplementos Dietéticos , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/prevención & control , Salmonella enteritidis , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Heces/microbiología , Femenino , Masculino , Salmonelosis Animal/microbiología
12.
Bioresour Technol ; 99(11): 4749-54, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17980581

RESUMEN

A study was undertaken to investigate the influence of protein concentration and the addition of different doses of endopeptidase (Alcalase) and exopeptidase (Flavourzyme) on the sequential enzymatic hydrolysis of a protein concentrate obtained from defatted sunflower wholemeal. The results show that the greatest degree of hydrolysis (37.8%) is achieved by hydrolyzing an aqueous substrate with a 5% protein concentrate, and using a 0.02 g Alcalase/g of protein concentrate of the substrate. The aminograms performed reveal that the free amino acid found in the highest proportion in the hydrolysate was aspartic acid, which accounted for over 50% of the free amino acids present, regardless of the substrate concentration and the enzyme dosage used. Finally, the hydrolysate obtained from a substrate containing a 5% protein concentrate and a 0.02 g Alcalase/g of protein concentrate displayed characteristics that indicate its suitability for use as a vegetable-origin plant growth regulator.


Asunto(s)
Aminoácidos/biosíntesis , Helianthus/metabolismo , Proteínas de Plantas/metabolismo , Cromatografía en Gel , Hidrólisis , Subtilisinas/metabolismo
13.
Eur J Trauma Emerg Surg ; 44(4): 519-526, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28929283

RESUMEN

PURPOSE: Prophylactic placement of endovascular balloon occlusion catheters has grown to be part of the surgical plans to control intraoperative hemorrhage in cases of abnormal placentation. We performed a systematic literature review to investigate the safety and effectiveness of the use of REBOA during cesarean delivery in pregnant woman with morbidly adherent placenta. METHODS: A systematic review was performed. Relevant case reports and nonrandomized studies were identified by the literature search in MEDLINE. We included studies involving pregnant woman with diagnosis of abnormal placentation who underwent cesarean delivery with REBOA placed for hemorrhage control. MINORS' criteria were used to evaluate the risk of bias of included studies. A formal meta-analysis was not performed. RESULTS: Eight studies were included in cumulative results. These studies included a total of 392 patients. Overall, REBOA was deployed in 336 patients. Six studies reported the use of REBOA as an adjunct for prophylactic hemorrhage control in pregnant woman with diagnosis of morbidly adherent placenta undergoing elective cesarean delivery. In two studies, REBOA was deployed in patients already in established hemorrhagic shock at the moment of cesarean delivery. REBOA was deployed primarily by interventional radiologists; however, one study reported a surgeon as the REBOA provider. The results from our qualitative synthesis indicate that the use of REBOA during cesarean delivery resulted in less blood loss with a low rate complications occurrence. CONCLUSION: REBOA is a feasible, safe, and effective means of prophylactic and remedial hemorrhage control in pregnant women with abnormal placentation undergoing cesarean delivery.


Asunto(s)
Aorta , Oclusión con Balón/métodos , Pérdida de Sangre Quirúrgica/prevención & control , Cesárea , Placenta Accreta , Hemorragia Posparto/prevención & control , Adulto , Femenino , Humanos , Embarazo , Resucitación/métodos
14.
J Clin Invest ; 104(10): 1375-82, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10562299

RESUMEN

A hallmark of asthma is mucin overproduction, a condition that contributes to airway obstruction. The events responsible for mucin overproduction are not known but are thought to be associated with mediators of chronic inflammation. Others have shown that T-helper 2 (Th2) lymphocytes are required for mucous cell metaplasia, which then leads to mucin overproduction in animal models of allergy. We hypothesized that Th2 cell mediators are present in asthmatic airway fluid and directly stimulate mucin synthesis in airway epithelial cells. Results in cultured airway epithelial cells showed that samples of asthmatic fluid stimulated mucin (MUC5AC) synthesis severalfold more potently than non-asthmatic fluid. Consistent with this, lavage fluid from the airways of allergen-challenged dogs stimulated mucin synthesis severalfold more potently than that from non-allergen-challenged dogs. Fractionation of dog samples revealed 2 active fractions at <10 kDa and 30-100 kDa. Th2 cytokines in these molecular weight ranges are IL-9 (36 kDa), IL-5 (56 kDa), and IL-13 (10 kDa). Antibody blockade of ligand-receptor interaction for IL-9 (but not IL-5 or IL-13) inhibited mucin stimulation by dog airway fluid. Furthermore, recombinant IL-9, but not IL-5 or IL-13, stimulated mucin synthesis. These results indicate that IL-9 may account for as much as 50-60% of the mucin-stimulating activity of lung fluids in allergic airway disease.


Asunto(s)
Alérgenos , Asma/fisiopatología , Interleucina-9/fisiología , Mucinas/genética , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Células Th2/inmunología , Transcripción Genética , Adulto , Animales , Asma/inmunología , Asma/metabolismo , Asma/patología , Bronquios/citología , Bronquios/patología , Células Cultivadas , Citocinas/análisis , Perros , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interleucina-9/genética , Interleucinas/análisis , Interleucinas/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Mucina 5AC , Mucinas/biosíntesis , Receptores de Interleucina/análisis , Receptores de Interleucina/genética , Receptores de Interleucina-9 , Proteínas Recombinantes/farmacología , Mucosa Respiratoria/patología , Tráquea/citología , Tráquea/patología , Transcripción Genética/efectos de los fármacos , Células Tumorales Cultivadas
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(1 Pt 2): 017402, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17677605

RESUMEN

Experimental conditions have recently been reported [G. Andresen, Phys. Rev. Lett. 98, 023402 (2007)] that are relevant to the prospect of trapping antihydrogen atoms. An analysis of the experimental conditions indicates that positron space charge can have an important effect. The fraction of antiprotons that have an energy suitable for antihydrogen trapping can be reduced by drifts caused by the presence of positron space charge.

16.
J Hazard Mater ; 147(1-2): 60-6, 2007 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-17254706

RESUMEN

This article describes a methodology to model the degree of remedial action required to make short stretches of a roadway suitable for dangerous goods transport (DGT), particularly pollutant substances, using different variables associated with the characteristics of each segment. Thirty-one factors determining the impact of an accident on a particular stretch of road were identified and subdivided into two major groups: accident probability factors and accident severity factors. Given the number of factors determining the state of a particular road segment, the only viable statistical methods for implementing the model were machine learning techniques, such as multilayer perceptron networks (MLPs), classification trees (CARTs) and support vector machines (SVMs). The results produced by these techniques on a test sample were more favourable than those produced by traditional discriminant analysis, irrespective of whether dimensionality reduction techniques were applied. The best results were obtained using SVMs specifically adapted to ordinal data. This technique takes advantage of the ordinal information contained in the data without penalising the computational load. Furthermore, the technique permits the estimation of the utility function that is latent in expert knowledge.


Asunto(s)
Inteligencia Artificial , Contaminación Ambiental/prevención & control , Sustancias Peligrosas , Administración de la Seguridad , Transportes/normas , Accidentes de Tránsito/prevención & control , Metodologías Computacionales , Sistemas Especialistas
17.
Bioresour Technol ; 97(3): 522-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16216734

RESUMEN

The process that permits the ability to obtain a protein extract from defatted sunflower flour also produces a solution very rich in phosphorus (P) and potassium (K), which also contains small concentrations of humic substances. The aim of this study has been to determine the possible agricultural use of this extract. Therefore the phosphorus-potassium solution (experimental solution) was analyzed to determinate its pH and its content of nitrogen, proteins, organic carbon, humic substances potassium and phosphorous. The experimental solution was applied on rye-grass (Lolium multiflorum Lam.) and afterwards the results were analyzed we calculated the germination percentage and the fresh and dry weights that were obtained after each cut throughout the duration of the experiment. In addition the different pigment types (chlorophyll a, chlorophyll b and carotenoids) were quantified. The conclusions of the study examine how this time-stable experimental solution improves the long-term effects and also the level of pigments, especially carotenoids, of the plants that have been treated.


Asunto(s)
Harina , Helianthus/química , Lolium/crecimiento & desarrollo , Lolium/metabolismo , Proteínas de Plantas/aislamiento & purificación , Fósforo/metabolismo , Fósforo/farmacología , Proteínas de Plantas/química , Potasio/metabolismo , Potasio/farmacología , Soluciones
18.
Cancer Res ; 60(13): 3419-24, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10910050

RESUMEN

Human carcinoembryonic antigen (CEA), a widely used tumor marker, and CEACAM6 [formerly nonspecific cross-reacting antigen (NCA)] are up-regulated in many types of human cancers, whereas family member CEACAM1 [formerly biliary glycoprotein (BGP)] is usually down-regulated. Deregulated overexpression of CEA/CEACAM6 but not CEACAM1 can inhibit the differentiation and disrupt the polarization and tissue architecture of many different types of cells. In this report, we show that CEA and CEACAM6, but not CEACAM1, markedly inhibit the apoptosis of cells when deprived of their anchorage to the extracellular matrix, a process known as anoikis. By blocking this tissue architecture surveillance mechanism, the architectural perturbation initiated by CEA/CEACAM6 can thus be maintained.


Asunto(s)
Apoptosis/fisiología , Antígeno Carcinoembrionario/fisiología , Moléculas de Adhesión Celular , Glicoproteínas de Membrana/fisiología , Animales , Antígenos CD , Antígenos de Neoplasias/fisiología , Adhesión Celular , Línea Celular , Neoplasias Colorrectales , Perros , Proteínas Ligadas a GPI , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/patología , Mucosa Intestinal/fisiología , Modelos Biológicos , Ratas , Proteínas Recombinantes/metabolismo , Transfección
19.
Rev. méd. Chile ; 149(12): 1723-1736, dic. 2021. ilus, tab
Artículo en Español | LILACS | ID: biblio-1389410

RESUMEN

BACKGROUND: Quarantines may exacerbate the presence of emotional symptoms or anxiety. AIM: To explore the relation between time spent in lockdown and development of depressive and anxiety symptoms. MATERIAL AND METHODS: A survey including the GAD anxiety and PHQ-9 depression scores was answered online by 1,488 subjects aged 36 ± 14 years (74% women), invited to participate through social networks. Both scores are validated for the Chilean population. RESULTS: Most responders had a private health insurance system. Sixty seven percent had clinically significant depressive symptoms and 39% had anxiety symptoms. Spending four or more weeks of lockdown (quarantine) was associated with 1.6 times higher risk of developing depressive symptoms and 2.9 times higher risk of developing anxiety symptoms. Difficulties in access to health care increased 3.3 times the risk of developing depression. Suffering a respiratory disease increased 2.39 times the risk of developing anxiety. CONCLUSIONS: There was a direct association between depressive and anxious symptoms, and the time spent of quarantine.


Asunto(s)
Humanos , Masculino , Femenino , Cuarentena/psicología , Depresión/etiología , Depresión/psicología , Depresión/epidemiología , Ansiedad/epidemiología , Trastornos de Ansiedad , Cuestionario de Salud del Paciente
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(4 Pt 2): 046406, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16383544

RESUMEN

The classical trajectory of an initially unbound positron within the electric field of an antiproton and a uniform magnetic field is simulated in three dimensions. Several simulations are run incorporating experimental parameters used for antihydrogen production, which has been achieved by two different groups [M. Amoretti, Nature (London) 419, 456 (2002); G. Gabrielse, Phys. Rev. Lett. 89, 213401 (2002)]. The simulations indicate that temporary bound states of antihydrogen can form at positive energies, where the energy of the system is defined to be zero when the positron and antiproton are at rest with infinite separation. Such quasibound states, which form only when the magnetic field is present, are typically smaller than in a dimension perpendicular to the magnetic field. An analytical model is developed for a formation cross section, and it is found that quasibound states may form more frequently than stable Rydberg states.

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