2,144 research outputs found
Uso del Tiempo en el Aula. Instituciones Educativas de nivel Secundaria 2013
El estudio arroja como resultados que en las aulas de quinto año de secundaria, a nivel nacional, las IIEE dedican aproximadamente el 70.6% del tiempo a actividades académicas. Mientras que el tiempo dedicado a actividades no académicas resultó ser de 29%. De este porcentaje, el 19.4% de las actividades estuvo destinada a la administración de la clase y de disciplina; y el 9.6% fue tiempo en el que el docente no se encontraba involucrado con la clase (por ejemplo, casos en los que el docente se encontraba fuera del aula)
ACUTE EFFECTS OF VOLUME-ORIENTED INCENTIVE SPIROMETRY ON CHEST WALL VOLUMES IN PATIENTS AFTER STROKE.
The aim of the present study was to assess how volume-oriented incentive spirometry (IS) applied to patients after stroke modify total and compartmental chest wall volume variations, including right and left hemithorax compared to controls.20 post-stroke patients (stroke group, SG) and 20 age-matched healthy subjects (control group, CG) were studied by optoelectronic plethysmography during spontaneous quiet breathing (QB), IS and in the recovery period after IS.IS determined an increase of chest wall volume and its rib cage and abdominal compartments in both groups (p = 0.0008) and between the three instances (p < 0.0001). Compared to healthy control subjects, tidal volume of patients with stroke was 24.7\%, 18\% and 14.7\% lower during QB, , IS and post-IS, respectively. In all the three conditions the contribution of the abdominal compartment to tidal volume was greater in the stroke patients (54.1, 43.2 and 48.9\%) than controls (43.7, 40.8 and 46.1\%, p = .039). In the vast majority of patients 13/20 and 18/20 during QB and IS, respectively), abdominal expansion led rib cage expansion during inspiration. A greater asymmetry between the right and left hemithoracic expansion occurred in stroke patients compared to controls but it decreased during IS (62.5\% (p = 0.0023) QB; 19.7\% IS; and 67.6\% (p = 0.135) post-IS.IS promotes an increased expansion in all compartments of the chest wall and reduces the asymmetric expansion between right and left pulmonary rib cage and therefore it should be considered as a tool for rehabilitation
Biologia, exigências térmicas e tabela de vida de fertilidade do ácaro-branco Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) em videira (Vitis vinifera L.) cv. Itália
Application of PEG400 in the one-pot synthesis of 7-[4-alkyl- or (hetero) aryl-1H-1,2,3-triazol-1-yl]thieno[3,2-b]pyridines via SNAr and Cu(I)- Catalyzed Azide-Alkyne Cycloaddition and preliminary evaluation of their anti-tumour activity
Several novel 7-[4-alkyl- or (hetero)aryl-1H-1,2,3-triazol-1-yl]thieno[3,2-b]pyridines were prepared in
good to high yields, using the environmentally friendly solvent PEG400 in a one-pot procedure from 7-
chlorothieno[3,2-b]pyridine to form the corresponding azide via SNAr with NaN3, followed by Cu(I)-catalyzed
Azide-Alkyne Cycloaddition (CuAAC) using different types of alkynes. This one-pot reaction in
PEG400 starting from a halogenated heteroaromatic system is reported for the first time and demonstrated
a wide scope of application for alkynes. Preliminary anti-tumour activity on human tumour cell
lines using the prepared 1,4-di(hetero)aryl-1,2,3-triazoles was evaluated, together with their toxicity in
non-tumour cells. Among the tested compounds the most promising one was a 2-ethynylpyridine
derivative.Fundação para a Ciência e Tecnologia (FCT)–Portugal financially
supports CQUM (UID/QUI/686/2019), CIMO-IPBragança (UID/
AGR/690/2019), the research project PTDC/QUI-QFI/28020/2017
(POCI-01-0145-FEDER-028020) also financed by European Regional Development Fund (ERDF), COMPETE2020 and Portugal2020,
the PTNMR network also supported by Portugal2020
and the PhD grant of J.M.R. (SFRH/BD/115844/2016) also financed
by ESF (European Social Fund) and HCOP (Human Capital Operational
Programme).info:eu-repo/semantics/publishedVersio
Three electrode electrochemical microfluidic cell: construction and characterization
This work describes the construction and characterization of an electrochemical flow-through microcell with the three electrodes (working, pseudo-reference, and auxiliary) inserted in microchannels with thickness smaller than 20 µm. These microchannels were constructed between two stacked polycarbonate slides using one or more overlapped toner masks as spacer. This strategy allows the construction of microcells with a variable internal volume on the working electrode (0.6 to 2.4 µL). Three different materials were optimized as electrodes: gold film or graphite-epoxy composite as working electrode, silver-epoxy composite as pseudo-reference electrode and, graphite-epoxy composite as auxiliary electrode. The performance of the microfluidic cell was characterized by cyclic voltammetry, potentiometric stripping analysis at constant current, and square wave anodic stripping voltammetry using ferrocyanide and heavy metals (Cu2+, Hg2+, Pb2+, and Cd2+) as model analytes
Preparation of a Nanoemulsion with Carapa guianensis
Andiroba (Carapa guianensis) seeds are the source of an oil with a wide range of biological activities and ethnopharmacological uses. However, few studies have devoted attention to innovative formulations, including nanoemulsions. The present study aimed to obtain a colloidal system with the andiroba oil using a low-energy and organic-solvent-free method. Moreover, the preliminary residual larvicidal activity of the nanoemulsion against Aedes aegypti was evaluated. Oleic and palmitic acids were the major fatty acids, in addition to the phytosterol β-sitosterol and limonoids (tetranortriterpenoids). The required hydrophile-lipophile was around 11.0 and the optimal nanoemulsion was obtained using polysorbate 85. The particle size distribution suggested the presence of small droplets (mean diameter around 150 nm) and low polydispersity index (around 0.150). The effect of temperature on particle size distribution revealed that no major droplet size increase occurred. The preliminary residual larvicidal assay suggested that the mortality increased as a function of time. The present study allowed achievement of a potential bioactive oil in water nanoemulsion that may be a promising controlled release system. Moreover, the ecofriendly approach involved in the preparation associated with the great bioactive potential of C. guianensis makes this nanoemulsion very promising for valorization of this Amazon raw material
A“Dirty” Footprint: Macroinvertebrate diversity in Amazonian Anthropic Soils
International audienceAmazonian rainforests, once thought to be pristine wilderness, are increasingly known to have been widely inhabited, modified, and managed prior to European arrival, by human populations with diverse cultural backgrounds. Amazonian Dark Earths (ADEs) are fertile soils found throughout the Amazon Basin, created by pre-Columbian societies with sedentary habits. Much is known about the chemistry of these soils, yet their zoology has been neglected. Hence, we characterized soil fertility, macroinvertebrate communities, and their activity at nine archeological sites in three Amazonian regions in ADEs and adjacent reference soils under native forest (young and old) and agricultural systems. We found 673 morphospecies and, despite similar richness in ADEs (385 spp.) and reference soils (399 spp.), we identified a tenacious pre-Columbian footprint, with 49% of morphospecies found exclusively in ADEs. Termite and total macroinvertebrate abundance were higher in reference soils, while soil fertility and macroinvertebrate activity were higher in the ADEs, and associated with larger earthworm quantities and biomass. We show that ADE habitats have a unique pool of species, but that modern land use of ADEs decreases their populations, diversity, and contributions to soil functioning. These findings support the idea that humans created and sustained high-fertility ecosystems that persist today, altering biodiversity patterns in Amazonia
Aging-related predictive factors for oxygenation improvement and mortality in COVID-19 and acute respiratory distress syndrome (ARDS) patients exposed to prone position: A multicenter cohort study
Background: Elderly patients are more susceptible to Coronavirus Disease-2019 (COVID-19) and are more likely to develop it in severe forms, (e.g., Acute Respiratory Distress Syndrome [ARDS]). Prone positioning is a treatment strategy for severe ARDS; however, its response in the elderly population remains poorly understood. The main objective was to evaluate the predictive response and mortality of elderly patients exposed to prone positioning due to ARDS-COVID-19.
Methods: This retrospective multicenter cohort study involved 223 patients aged ≥ 65 years, who received prone position sessions for severe ARDS due to COVID-19, using invasive mechanical ventilation. The PaO2/FiO2 ratio was used to assess the oxygenation response. The 20-point improvement in PaO2/FiO2 after the first prone session was considered for good response. Data were collected from electronic medical records, including demographic data, laboratory/image exams, complications, comorbidities, SAPS III and SOFA scores, use of anticoagulants and vasopressors, ventilator settings, and respiratory system mechanics. Mortality was defined as deaths that occurred until hospital discharge.
Results: Most patients were male, with arterial hypertension and diabetes mellitus as the most prevalent comorbidities. The non-responders group had higher SAPS III and SOFA scores, and a higher incidence of complications. There was no difference in mortality rate. A lower SAPS III score was a predictor of oxygenation response, and the male sex was a risk predictor of mortality.
Conclusion: The present study suggests the oxygenation response to prone positioning in elderly patients with severe COVID-19-ARDS correlates with the SAPS III score. Furthermore, the male sex is a risk predictor of mortality
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV
A search for new physics is presented based on an event signature of at least
three jets accompanied by large missing transverse momentum, using a data
sample corresponding to an integrated luminosity of 36 inverse picobarns
collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector
at the LHC. No excess of events is observed above the expected standard model
backgrounds, which are all estimated from the data. Exclusion limits are
presented for the constrained minimal supersymmetric extension of the standard
model. Cross section limits are also presented using simplified models with new
particles decaying to an undetected particle and one or two jets
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