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1.
Sensors (Basel) ; 24(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38793995

RESUMEN

A broadband differential-MMIC low-noise amplifier (DLNA) using metamorphic high-electron-mobility transistors of 70 nm in Gallium Arsenide (70 nm GaAs mHEMT technology) is presented. The design and results of the performance measurements of the DLNA in the frequency band from 1 to 16 GHz are shown, with a high dynamic range, and a noise figure (NF) below 1.3 dB is obtained. In this work, two low-noise amplifiers (LNAs) were designed and manufactured in the OMMIC foundry: a dual LNA, which we call balanced, and a differential LNA, which we call DLNA. However, the paper focuses primarily on DLNA because of its differential architecture. Both use a 70 nm GaAs mHEMT space-qualified technology with a cutoff frequency of 300 GHz. With a low power bias Vbias/Ibias (5 V/40.5 mA), NF < 1.07 dB "on wafer" was achieved, from 2 to 16 GHz; while with the measurements made "on jig", NF = 1.1 dB, from 1 to 10 GHz. Furthermore, it was obtained that NF < 1.5 dB, from 1 to 16 GHz, with a figure of merit equal to 145.5 GHz/mW. Finally, with the proposed topology, several LNAs were designed and manufactured, both in the OMMIC process and in other foundries with other processes, such as UMS. The experimental results showed that the NF of the DLNA MMIC with multioctave bandwidth that was built in the frequency range of the L-, S-, C-, and X-bands was satisfactory.

2.
ACS Sustain Chem Eng ; 12(7): 2771-2782, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38389903

RESUMEN

Potassium exchanged Sn-ß and Sn-USY zeolites have been tested for the transformation of various aldoses (hexoses and pentoses), exhibiting outstanding catalytic activity and selectivity toward methyl lactate. Insights into the transformation pathways using reaction intermediates-dihydroxyacetone and glycolaldehyde-as substrates revealed a very high catalytic proficiency of both zeolites in aldol and retro-aldol reactions, showcasing their ability to convert small sugars into large sugars, and vice versa. This feature makes the studied Sn-zeolites outstanding catalysts for the transformation of a wide variety of sugars into a limited range of commercially valuable alkyl lactates and derivatives. [K]Sn-ß proved to be superior to [K]Sn-USY in terms of shape selectivity, exerting tight control on the distribution of produced α-hydroxy methyl esters. This shape selectivity was evident in the transformation of several complex sugar mixtures emulating different hemicelluloses-sugar cane bagasse, Scots pine, and white birch-that, despite showing very different sugar compositions, were almost exclusively converted into methyl lactate and methyl vinyl glycolate in very similar proportions. Moreover, the conversion of a real hemicellulose hydrolysate obtained from Scots pine through a simple GVL-based organosolv process confirmed the high activity and selectivity of [K]Sn-ß in the studied transformation, opening new pathways for the chemical valorization of this plentiful, but underutilized, sugar feedstock.

3.
Sensors (Basel) ; 23(23)2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38067975

RESUMEN

In this paper, the precise design of a high-power amplifier (HPA) is shown, along with the problems associated with the stability of "on-wafer" measurements. Here, techniques to predict possible oscillations are discussed to ensure the stability of a monolithic microwave-integrated circuit (MMIC). In addition, a deep reflection is made on the instabilities that occur when measuring both on wafer and using a mounted chip. Stability techniques are used as tools to characterize measurement results. Both a precise design and instabilities are shown through the design of a three-stage X-band HPA in gallium nitride (GaN) from the WIN Semiconductors Corp. foundry. As a result, satisfactory performance was obtained, achieving a maximum output power equal to 42 dBm and power-added efficiency of 32% at a 20 V drain bias. In addition to identifying critical points in the design or measurement of the HPA, this research shows that the stability of the amplifier can be verified through a simple analysis and that instabilities are often linked to errors in the measurement process or in the characterization of the measurement process.

4.
Sensors (Basel) ; 22(22)2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-36433581

RESUMEN

In this paper, a comparative analysis between the PM2.5 concentration in downtown Quito, Ecuador, during the COVID-19 pandemic in 2020 and the previous five years (from 2015 to 2019) was carried out. Here, in order to fill in the missing data and achieve homogeneity, eight datasets were constructed, and 35 different estimates were used together with six interpolation methods to put in the estimated value of the missing data. Additionally, the quality of the estimations was verified by using the sum of squared residuals and the following correlation coefficients: Pearson's r, Kendall's τ, and Spearman's ρ. Next, feature vectors were constructed from the data under study using the wavelet transform, and the differences between feature vectors were studied by using principal component analysis and multidimensional scaling. Finally, a robust method to impute missing data in time series and characterize objects is presented. This method was used to support the hypothesis that there were significant differences between the PM2.5 concentration in downtown Quito in 2020 and 2015-2019.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Control de Enfermedades Transmisibles , Proyectos de Investigación , Material Particulado
5.
ACS Sustain Chem Eng ; 10(27): 8885-8896, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35846797

RESUMEN

Sn-USY materials have been prepared through an optimized post-synthetic catalytic metalation procedure. These zeolites displayed, upon ion exchange with alkaline metals, an outstanding activity in the direct transformation of glucose into methyl lactate, yielding more than 70% of the starting glucose as the target product, and an overall combined retro-aldol condensation product yield above 95% in a short reaction time (<4 h). This outstanding catalytic performance is ascribed to the neutralization of Brønsted acid sites, the consequent depression of side reactions, and a higher population of tin open sites in the ion-exchanged Sn-USY zeolites. Reusability tests evidenced some loss of catalytic activity, partially caused by the closing of tin sites, although the use of small amounts of water in the reaction media demonstrated that this deactivation mechanism can be, at least, partially alleviated.

6.
Contemp Nurse ; 57(3-4): 280-289, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34709980

RESUMEN

BACKGROUND: Chronic pain has a disproportionate impact on members of vulnerable population groups, and women are at substantially greater risk than men of suffering multiple chronic pain disorders. Moreover, one of the aspects most affected by the presence of chronic pain is that of health-related quality of life (HRQoL), worsening over time, as the disease persists. OBJECTIVES: To describe the profile of patients who suffer non-malignant chronic pain, from a gender perspective, and to identify factors related to their HRQoL and mental health. DESIGN: A cross-sectional study was carried out in patients with chronic non-cancer pain. METHODS: Sociodemographic variables, pain intensity at rest and in motion, SF-36 health questionnaire, anxiety, and depression were evaluated. RESULTS: The study population consisted of 531 subjects, of whom 64.2% were women. The mean age was 52.9 (SD: 10.4) years. The pain intensity recorded on the visual analogue scale was 6 (SD: 2.7) at rest and 8 (SD: 2) in motion. Physical component score and mental component score of quality of life were worse in women vs men: 33.73 (6.77) vs 32.33 (6.20), for the physical component; 36.89 (12.77) vs 32.91 (11.51), for mental component. Anxiety, depression and pain intensity, showed poorer results in women. CONCLUSION: Gender is a factor that should be considered in assessing and managing chronic pain, due to its influence on the perception of pain, and HRQoL. IMPACT STATEMENT: Gender is an important modifier of the perception of pain, and HRQoL. To achieve a patient-centred approach, nurses should incorporate gender as a differential factor to adapt and individualize pain management and patient education.


Asunto(s)
Dolor Crónico , Calidad de Vida , Analgésicos Opioides , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción del Dolor , Factores Sexuales , Encuestas y Cuestionarios
7.
Sensors (Basel) ; 21(1)2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33401639

RESUMEN

This paper analyzes 12 years of tropospheric ozone (O3) concentration measurements using robust techniques. The measurements were taken at an air quality monitoring station called Belisario, which is in Quito, Ecuador; the data collection time period was 1 January 2008 to 31 December 2019, and the measurements were carried out using photometric O3 analyzers. Here, the measurement results were used to build variables that represented hours, days, months, and years, and were then classified and categorized. The index of air quality (IAQ) of the city was used to make the classifications, and robust and nonrobust confidence intervals were used to make the categorizations. Furthermore, robust analysis methods were compared with classical methods, nonparametric methods, and bootstrap-based methods. The results showed that the analysis using robust methods is better than the analysis using nonrobust methods, which are not immune to the influence of extreme observations. Using all of the aforementioned methods, confidence intervals were used to both establish and quantify differences between categories of the groups of variables under study. In addition, the central tendency and variability of the O3 concentration at Belisario station were exhaustively analyzed, concluding that said concentration was stable for years, highly variable for months and hours, and slightly changing between the days of the week. Additionally, according to the criteria established by the IAQ, it was shown that in Quito, the O3 concentration levels during the study period were not harmful to human health.

8.
J Adv Nurs ; 77(1): 255-265, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33136314

RESUMEN

AIMS: To determine the effect of a comprehensive nurse-led programme for patients with chronic non-malignant pain, on quality of life, level of pain, anxiety, and depression, as primary outcomes and patients' satisfaction as a secondary end point. DESIGN: An open-label randomized controlled trial was carried out. METHODS: The experimental group received both a nurse-led intervention on healthy lifestyles, education on self-esteem, pain awareness, communication, and relaxation techniques. The control group received usual care. Quality of life, level of pain, anxiety, and depression were the main outcomes. Data were obtained at baseline, immediately after the intervention, and 6 and 9 months. The study was carried out from 2015-2017. RESULTS: The sample was composed of 279 patients. At 9 months, the effect size (non-parametric effect size statistic A) favoured the intervention group for SF-36 mental health score (A = 0.79; 95% CI: 0.73-0.85), anxiety (A = 0.58; 95% CI: 0.51-0.65), pain intensity (A = 0.57; 95% CI: 0.51-0.64), and depression (A = 0.58; 95% CI: 0.51-0.65). Smaller differences were found on physical scores between the intervention and the usual care group. Patients showed a high level of satisfaction with the introduced intervention. CONCLUSION: A comprehensive nurse-led programme for patients with chronic non-malignant pain has a positive impact on their quality of life, level of pain, and mental health. IMPACT: Studies have reported that the problem of chronic pain is not optimally controlled. A structured nurse-led programme has been tested to facilitate healthy behaviours to help patients manage their chronic pain and to provide them with the necessary tools for their self-care. This nurse-led intervention improved their mental health and decreased their level of pain.


Asunto(s)
Dolor Crónico , Calidad de Vida , Ansiedad/prevención & control , Humanos , Rol de la Enfermera , Autocuidado
11.
J Manag Care Pharm ; 18(4): 311-23, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22548691

RESUMEN

BACKGROUND: Although some studies have demonstrated that pharmacist intervention can improve drug therapy among patients with cardiovascular disease (CVD), more evidence derived from randomized controlled trials (RCTs) is needed, including assessment of the effect of community pharmacist interventions in patients with CVD. OBJECTIVE: To assess the effectiveness of the Dader Method for pharmaceutical care on achieving therapeutic goals for blood pressure (BP), total cholesterol (TC), and both BP and TC (BP/TC) in patients with CVD and/or high or intermediate cardiovascular (CV) risk attending community pharmacies in Spain. METHODS: Patients aged 25 to 74 years attending community pharmacies with a prescription for at least 1 drug indicated for CVD or CV risk factors were randomized to 2 groups: an intervention group that received pharmaceutical care, which was provided by specially trained pharmacists working in collaboration with physicians, and a control group that received usual care (routine dispensing counseling) and verbal and written counseling regarding CVD prevention. Patients were recruited from December 2005 to September 2006, and both groups were followed for 8 months. Study outcomes were assessed at baseline and at 16 and 32 weeks after randomization. The primary outcome measures were the proportions of patients achieving BP, TC, and BP/TC therapeutic goals (BP lower than 140/90 mm Hg for patients with uncomplicated hypertension and lower than 130/80 mm Hg for patients with diabetes, chronic kidney disease, or history of myocardial infarction or stroke; TC lower than 200 mg per dL for patients without CVD and lower than 175 mg per dL for patients with CVD). Secondary outcomes were mean BP and TC values. BP was assessed manually by the pharmacist after a 10-minute rest in the supine position. This measurement was performed twice for every participant, and the average of the 2 measurements was calculated. TC was measured by the pharmacist during the study visit using the enzymatic dry method. Statistical analyses were performed using 2-tailed McNemar tests, Pearson chi-square tests, and Student's t-tests; P < 0.05 was considered statistically significant. RESULTS: 714 patients were included in the study (356 intervention, 358 control), and the mean [SD] age was 62.8 [8.1] years. The 2 groups were similar at baseline in clinical and demographic characteristics, including the proportion of patients at therapeutic goals for BP, TC, and BP/TC. After 8 months of follow-up, there were statistically significant differences in favor of pharmaceutical care in the proportions of patients who achieved therapeutic goals for BP (52.5% vs. 43.0%, P=0.017), TC (56.5% vs. 44.1%, P=0.001), and BP/TC (37.1% vs. 21.8%, P < 0.001). CONCLUSION: Compared with usual care plus written education, pharmaceutical care focused on patient evaluation and follow-up in collaboration with physicians improved the achievement of BP, TC, and BP/TC treatment goals in patients with CVD and/or high or intermediate CV risk attending community pharmacies in Spain.


Asunto(s)
Presión Sanguínea , Enfermedades Cardiovasculares/tratamiento farmacológico , Colesterol/sangre , Servicios Comunitarios de Farmacia/organización & administración , Pacientes Ambulatorios , Adulto , Anciano , Determinación de la Presión Sanguínea , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Factores de Riesgo , España
12.
Med Clin (Barc) ; 124(7): 250-5, 2005 Feb 26.
Artículo en Español | MEDLINE | ID: mdl-15743589

RESUMEN

BACKGROUND AND OBJECTIVE: Medication-related problems (MRPs) are health problems resulting from patient pharmacotherapy failure that interfere with the expected outcome in the patient's health status. The aim of this study was to discover the health problems associated with the appearance of MRPs. PATIENTS AND METHOD: Patient interviews, together with the assessment of medical records were the sources of information used in the assessment and identification of MRPs. A validated questionnaire was used for the interviews; in order to classify the health problems found, the ICD-9 was used. RESULTS: 2,556 patients were interviewed over a period of one year at a hospital emergency department. 2,261 of these cases were valid. Osteoarticular diseases, poorly defined signs and symptoms of illness, injuries and intoxications were the disorders most commonly associated with the appearance of MRPs. MRPs of necessity and effectiveness had a similar profile. MRPs of safety were more commonly associated with poorly defined signs and symptoms of illness, injuries and intoxications, as well as nervous, digestive and blood problems. CONCLUSIONS: Most frequent medication related health problems causing visits to hospital emergency departments were osteoarticular disorders, followed by poorly defined signs and symptoms of illness. Differences were observed in the diagnoses between the different dimensions and types of MRP.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Insuficiencia del Tratamiento
13.
Med. clín (Ed. impr.) ; 124(7): 250-255, feb. 2005. tab, graf
Artículo en Es | IBECS | ID: ibc-036483

RESUMEN

FUNDAMENTO Y OBJETIVO: Los problemas relacionados con los medicamentos (PRM) son problemas de salud que se producen como consecuencia de fallos de la farmacoterapia del paciente y que interfieren con los resultados esperados de salud. El objetivo de este trabajo es conocer los problemas de salud más frecuentes que constituyen PRM. PACIENTES Y MÉTODO: La entrevista con el paciente junto con la evaluación de la historia clínica son las principales fuentes de información para evaluar e identificar PRM. Se utilizó un cuestionario validado como instrumento para la entrevista y la CIE-9 para la clasificación de los problemas de salud encontrados. RESULTADOS: Se entrevistó a un total de 2.556 pacientes durante 1 año en el servicio de urgencias hospitalario, de los que se estudiaron 2.261 tras las exclusiones. Las enfermedades osteoarticulares, los signos y síntomas mal definidos y las lesiones y envenenamientos son los problemas más relacionados con la aparición de PRM. Los PRM de necesidad y efectividad mantienen un perfil similar. Los PRM de seguridad se asociaron más a signos y síntomas mal definidos y lesiones y envenenamientos así como a alteraciones nerviosas, digestivas y sanguíneas. CONCLUSIONES: Los PRM más frecuentes que son causa de consulta en un servicio de urgencias hospitalario son los osteoarticulares, seguidos de los signos y síntomas mal definidos. Se observan diferencias en los diagnósticos entre las distintas dimensiones de PRM y sus tipos


BACKGROUND AND OBJECTIVE: Medication-related problems (MRPs) are health problems resulting-from patient pharmacotherapy failure that interfere with the expected outcome in the patient’s health status. The aim of this study was to discover the health problems associated with the appearance of MRPs. PATIENTS AND METHOD: Patient interviews, together with the assessment of medical records were the sources of information used in the assessment and identification of MRPs. A validated questionnaire was used for the interviews; in order to classify the health problems found, the ICD-9 was used. RESULTS: 2,556 patients were interviewed over a period of one year at a hospital emergency department.2,261 of these cases were valid. Osteoarticular diseases, poorly defined signs and symptoms of illness, injuries and intoxications were the disorders most commonly associated with the appearance of MRPs. MRPs of necessity and effectiveness had a similar profile. MRP sof safety were more commonly associated with poorly defined signs and symptoms of illness, injuries and intoxications, as well as nervous, digestive and blood problems. CONCLUSIONS: Most frequent medication related health problems causing visits to hospital emergency departments were osteoarticular disorders, followed by poorly defined signs and symptoms of illness. Differences were observed in the diagnoses between the different dimensions and types of MRP


Asunto(s)
Masculino , Femenino , Humanos , Servicios Médicos de Urgencia/estadística & datos numéricos , Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , /epidemiología , Sistemas de Medicación en Hospital/estadística & datos numéricos , Encuestas y Cuestionarios , Encuestas Epidemiológicas
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