495 research outputs found
Towards a Common Vision for Innovation: Making Sense of Complexity in a Health Sciences Program
The growing use of digital educational technologies in higher education has seen considerable change resulting in significant institutional energies directed towards maintaining currency with today’s emerging trends. The move to digital transformation is an inevitable assumption and generally positively accepted by academia. Despite this, technology integration has emerged in an ad hoc and reactive fashion rather than purposeful and strategic. This Organizational Improvement Plan (OIP) addresses the need for a shared vision for technology adoption across a health sciences program in a mid-sized institution. Although faculty participate enthusiastically in developing curricular initiatives, their roles and engagement with technology visioning are often void of their collective voices. The theoretical concepts of sensemaking and learning culture offer insight into the complexity of connecting technology to learning pedagogy. Central to developing capacity requires facilitating meaningful connections between users about the technology and the implications to practice. This OIP builds upon the need for a collaborative lens that acknowledges cultural nuances and individual empowerment. Key in the success of leading the process will be the enactment of adaptive and transformational leadership, where the approach for change is modelled in a collaborative and supportive manner. The change implementation plan of the proposed change is fostered by the dual application of Cawsey et al.’s (2016) Change Model and Kotter’s eight-stage process (2012). Ultimately, this OIP will result in an integrated visionary approach to technology adoption across a health science program
High order structure preserving explicit methods for solving linear-quadratic optimal control problems
[EN] We consider the numerical integration of linear-quadratic optimal control problems. This problem requires the solution of a boundary value problem: a non-autonomous matrix Riccati differential equation (RDE) with final conditions coupled with the state vector equation with initial conditions. The RDE has positive definite matrix solution and to numerically preserve this qualitative property we propose first to integrate this equation backward in time with a sufficiently accurate scheme. Then, this problem turns into an initial value problem, and we analyse splitting and Magnus integrators for the forward time integration which preserve the positive definite matrix solutions for the RDE. Duplicating the time as two new coordinates and using appropriate splitting methods, high order methods preserving the desired property can be obtained. The schemes make sequential computations and do not require the storrage of intermediate results, so the storage requirements are minimal. The proposed methods are also adapted for solving linear-quadratic N-player differential games. The performance of the splitting methods can be considerably improved if the system is a perturbation of an exactly solvable problem and the system is properly split. Some numerical examples illustrate the performance of the proposed methods.The author wishes to thank the University of California San Diego for its hospitality where part of this work was done. He also acknowledges the support of the Ministerio de Ciencia e Innovacion (Spain) under the coordinated project MTM2010-18246-C03. The author also acknowledges the suggestions by the referees to improve the presentation of this work.Blanes Zamora, S. (2015). High order structure preserving explicit methods for solving linear-quadratic optimal control problems. 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Health-related quality of life of primary caregivers of persons with paraplegia
Study Design: A cross-sectional descriptive study was performed with structured questionnaires and interviews conducted with 60 primary caregivers of persons with paraplegia (T1 to S2) owing to traumatic spinal cord injury (SCI).Objectives: the purpose of this study was the assessment of the health-related quality of life (HRQoL) of primary caregivers of persons with paraplegia owing to traumatic SCI.Setting: Sa oSa Paulo, SP, Brazil.Methods: the HRQoL was assessed by the Short Form-36 (SF-36) health survey questionnaire and caregiver burden was evaluated by the Caregiver Burden Scale (CBS).Results: Among 60 caregivers evaluated, 49 (81.7%) were female, with mean age of 35.8 (SD = 12.91) years, 16 (26.6%) being wives and 14 (23.4%) sisters of pe rsons with paraplegia. It was found that the caregivers spend an average of 11.3 h/ day caring for individuals with paraplegia. Twenty-three caregivers (38.3%) had a chronic disease and 32 (53.3%) were sole caregivers taking upon themselves the full responsibility of caring for the persons with paraplegia. the subjects reported lower scores on bodily pain and vitality than the other dimensions of the SF-36. the mean global CBS score was 1.71 (SD = 0.50) and mean scores for each dimension ranged from 1.39 (SD = 0.64) for emotional involvement to 2.44 (SD = 0.79) for environment dimension.Conclusion: the primary caregivers of spinal cord-injured persons reported low scores on all of the SF-36 and CBS dimensions, bodily pain and vitality being the SF-36 dimensions that received the lowest scores.Universidade Federal de São Paulo, Discipline Plast Surg, Div Plast Surg, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nursing, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Discipline Plast Surg, Div Plast Surg, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nursing, BR-04023062 São Paulo, BrazilWeb of Scienc
A rapid method for the in-field analysis of amphetamines employing the agilent bioanalyzer
This paper reports the first analysis of small molecules on the Agilent bio-analyser. The Bioanalyzer is a commercial lab-on-a-chip instrument designed for the analysis of DNA and proteins. We demonstrate that the instrument is suitable for analyses beyond its design specifications. Amphetamine, methamphetamine and pseudoephedrine were separated with a 50 mM borate and 50 mM sodium dodecyl sulfate (SDS) buffer at pH 9.66. The analytes were derivatised with fluorescein isothiocyanate (FITC) in 3 minutes with a heating block set at 90°C, reducing the typical time of 12 hours required for amine-labelling. Analytes were detected by LED-induced fluorescence (λ = 525 nm and λ = 470 nm). Furthermore, five amphetamine analogues were baseline separated within 1 minute. An average limit of detection of 0.6 mg mL -1 and limit of quantification of 2.2μ mg mL-1 were obtained for all analytes. These rapid analyses in conjunction with a fast and reliable derivatisation method with FITC demonstrate its potential use for the in-field analysis of samples of forensic significance. © 2011 The Royal Society of Chemistry
A portable explosive detector based on fluorescence quenching of pyrene deposited on coloured wax-printed μpADs
A new technique for the detection of explosives has been developed based on fluorescence quenching of pyrene on paper-based analytical devices (μPADs). Wax barriers were generated (150 °C, 5 min) using ten different colours. Magenta was found as the most suitable wax colour for the generation of the hydrophobic barriers with a nominal width of 120 μm resulting in fully functioning hydrophobic barriers. One microliter of 0.5 mg mL-1 pyrene dissolved in an 80 : 20 methanol-water solution was deposited on the hydrophobic circle (5 mm diameter) to produce the active microchip device. Under ultra-violet (UV) illumination, ten different organic explosives were detected using the μPAD, with limits of detection ranging from 100-600 ppm. A prototype of a portable battery operated instrument using a 3 W power UV light-emitting-diode (LED) (365 nm) and a photodiode sensor was also built and evaluated for the successful automatic detection of explosives and potential application for field-based screening. © 2013 The Royal Society of Chemistry
Percepción de los escolares sobre los accidentes y las lesiones accidentales
Antecedentes/Objetivos: Las lesiones no intencionales constituyen la primera causa de muerte en la población infantil española (1-14 años) con una tasa de mortalidad de 6,5 por 100.000 niñas/os. Según datos de la Encuesta Nacional de Salud de 2006, la incidencia acumulada de lesiones accidentales en el último año previo a la encuesta fue de 10,6% de las/os niños entrevistadas/os, más frecuente en niños (51,4%) que en niñas (48,6%). Los accidentes se produjeron con mayor frecuencia en casa (29%), en la calle (23%) y en la escuela (22%). Pocos estudios han investigado la perspectiva de las/os niñas/os sobre las lesiones accidentales que sufren. El objetivo del estudio es explorar, describir y categorizar las percepciones de las/os niñas/os sobre las lesiones accidentales y las explicaciones de los accidentes que hayan podido experimentar. Métodos: Estudio exploratorio mediante análisis cualitativo sobre la percepción de salud de la población infantil. Los datos se obtuvieron de 6 grupos de discusión de entre 8 a 10 niños/as formados en 2006 mediante muestreo teórico intencional de niños/as de edades entre 8 y 12 años de 3º y 6º curso de primaria de colegios públicos y concertados de Alicante con los criterios de inclusión: Centro público/concertado; Zona centro o residencial/zona de clase trabajadora; Niños/niñas/grupo mixto; Tercero y Sexto de primaria. Los discursos fueron grabados, transcritos y posteriormente analizados usando el programa ATLASTI.v.4.1 y aplicando los principios de la grounded theory. Dos investigadores identificaron una estructura temática y un proceso de codificación abierta revisada por un tercero para validar el proceso y determinar las categorías y subcategorías resultantes. Resultados: Los accidentes fue un tema emergente del análisis del discurso. Se identificaron las categorías y subcategorías: Conceptualización de accidente (a. Oposición a salud, “Un niño sano no se rompe nada” b. Asociado a enfermedad “Cuando te rompes la mano o la muñeca” c. Suceso inevitable “Es algo que no se puede prevenir”) Causa y tipo de lesiones (“Por mucho que me caiga sólo me he hecho moraos”) Lugares donde se producen accidentes (a. Escuela “El patio es plano y cuando juegas al futbol algún niño se cae” b. Otros “Me hice una fisura en la calle”) Sugerencias para evitar accidentes (a. Espacios escolares “Arreglar el suelo del patio” b. Conductas personales “Tener más cuidado”). Conclusiones: La población infantil sabe identificar los accidentes como problema de salud. Los percibe como inevitables aunque propone formas de evitarlos. Ayudar a los escolares a identificar las causas de los accidentes puede eliminar su percepción de inevitabilidad y fortalecer su capacidad para afrontarlos.Escuela Valenciana de Estudios en Salud. Generalitat Valenciana 044/2006
Detection of gunshot residues using mass spectrometry
In recent years, forensic scientists have become increasingly interested in the detection and interpretation of organic gunshot residues (OGSR) due to the increasing use of lead- and heavy metal-free ammunition. This has also been prompted by the identification of gunshot residue- (GSR-) like particles in environmental and occupational samples. Various techniques have been investigated for their ability to detect OGSR. Mass spectrometry (MS) coupled to a chromatographic system is a powerful tool due to its high selectivity and sensitivity. Further, modern MS instruments can detect and identify a number of explosives and additives which may require different ionization techniques. Finally, MS has been applied to the analysis of both OGSR and inorganic gunshot residue (IGSR), although the "gold standard" for analysis is scanning electron microscopy with energy dispersive X-ray microscopy (SEM-EDX). This review presents an overview of the technical attributes of currently available MS and ionization techniques and their reported applications to GSR analysis. © 2014 Regina Verena Taudte et al
Purification, characterization and molecular cloning of the major chitinase from Tenebrio molitor larval midgut
Insect chitinases are involved in degradation of chitin from the exoskeleton cuticle or from midgut peritrophic membrane during molts. cDNAs coding for insect cuticular and gut chitinases were cloned, but only chitinases from moulting fluid were purified and characterized. In this study the major digestive chitinase from T. molitor midgut (TmChi) was purified to homogeneity, characterized and sequenced after cDNA cloning. TmChi is secreted by midgut epithelial cells, has a molecular weight of 44 kDa and is unstable in the presence of midgut proteinases. TmChi shows strong substrate inhibition when acting on umbelliferyl-derivatives of chitobio- and chitotriosaccharides, but has normal Michaelis kinetics with the N-acetylglucosamine derivative as substrate. TmChi has very low activity against colloidal chitin, but effectively converts oligosaccharides to shorter fragments. The best substrate for TmChi is chitopentaose, with highest kcat/KM value. Sequence analysis and chemical modification experiments showed that the TmChi active site contains carboxylic groups and a tryptophane, which are known to be important for catalysis in family 18 chitinases. Modification with p-hidroximercuribenzoate of a cysteine residue, which is exposed after substrate binding, leads to complete inactivation of the enzyme. TmChi mRNA encodes a signal peptide plus a protein with 37 kDa and high similarity with other insect chitinases from family 18. Surprisingly, this gene does not encode the C-terminal Ser-Thr-rich connector and chitin-binding domain normally present in chitinases. The special features of TmChi probably result from its adaptation to digest chitin-rich food without damaging the peritrophic membrane. © 2006 Elsevier Ltd. All rights reserved
The influence of sonication on the thermal behavior of muscovite and biotite
The differences on the thermal behavior (DTA-TG) of mica samples measured
before and after sonication have been studied. Sonication treatment produces
important modifications in the thermal behavior of muscovite and biotite
samples. For muscovite, it produces a broadening and decrease in temperature of
the dehydroxylation and crystallization effects, reaching a steady stage after
40 h treatment time. For biotite, the original single peak profile for the
dehydroxylation of the untreated sample is converted into a two peaks profile
after sonication, the intensity of the low temperature peak increases with
sonication time, while the intensity of the high temperature peak decreases.
The modification of the thermal behavior for sonicated samples has been
correlated to the particle size distribution effect produced by the sonication
treatment. It has been also observed that the cup tip of the sonication
equipment contaminates the samples releasing titanium of its compositio
CSR and branding in emerging economies: The effect of incomes and education
Sustainable development is a fundamental objective for guaranteeing the future of the planet. Taking into account the impact of emerging economies on the global economy and the scarcity of papers that have considered the effect of CSR initiatives on consumer behavior on those economies, it seems that further research on this issue is necessary. In particular, we analyze the extent to which CSR affects the connection and links of the consumer to the brand (i.e., self–brand connection, brand engagement). The main contribution of the paper to the field is the analysis of the interaction between CSR and branding in the context of an emerging economy. To that aim, and also in a novel way, we use the Stimuli–Organism–Response (SOR) model for a sample of more than 400 food and beverage consumers in Metropolitan Lima, Peru. Our results show that CSR effectively acts as a stimulus for consumers to identify and link to brands and that, in addition, these links generate buy-back (i.e., loyalty) and recommendation behaviors (i.e., WOM) which, in turn, create a great commercial value for companies. This research also analyses how incomes and educational levels moderate the intensity of such links. For practical implications, global trends in managing CSR and branding may be useful, although some cross-cultural and context-specific adaptations are necessary
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