656 research outputs found
Marketing the service : basic social process in health visiting.
The present study was undertaken to provide an understanding of the
processes underlying health visiting practice. The research strategy selected
was grounded theory (Glaser and Strauss 1967, Strauss 1987, Strauss and
Corbin 1990). A total of 21 female health visitors from a District Health
Authority in the North West of England participated in the study. Data was
collected by means of 20 formal interviews and 41 days of participant
observation in four different health centres.
To recognize the basic social process in any interaction is one of the major
aspects of grounded theory. This requires the identification of the
"Phenomenon" which motivates the development of a process and the
conditions under which it operates. The basic problem or phenomenon in
health visiting uncovered in the data was "Securing Life Trajectories". This
forms the core of the health visitor's work. The general set of conditions
that influence health visiting work was identified as "Working Between Two
Worlds". This is used to describe the health visitor's position between the
policy agenda and the client's agenda. The process revealed in the data that
health visitors use to respond to this overall problem was "Marketing Health
Visiting". This refers to the different tactics that they use to introduce the
policy agenda into the client's domain. During this process the policy
agenda is adjusted to fit the client's circumstances. Three major strategies are identified in this process: 1) Promoting the service, 2) Adjusting delivery
and 3) Tailoring the content.
This study found that "Marketing Health Visiting" is a gradual process in
which the health visitor wins grounds as time passes. As marketing
strategies are implemented the conditions influencing the interaction change.
Hence it moves from taking place in what is labelled in this study as
"Dissociated Context", to a "Convergent Context" and finally to a "Shared
Context". The final consequence of implementing marketing strategies is
that of constructing "A Common Agenda" with clients. This agenda is
basically the personalisation and contextualization of health visiting services.
To build this common agenda it is of crucial importance that the client
should see and feel the need for the health visiting service as well as the
development of trust between the professional and the client. Hence the
relationship that is developed between them acts as an enabling factor for
reaching mutual collaboration.
The discussion of the study focuses on its significance within the actual
debate on health visiting about introducing new ways of practice. The health
visitor's overall role is examined and the importance of developing
relationships with clients is also highlighted
Casa del Ron Varadero: Evaluación como producto turístico
El trabajo se propone estudiar la evolución que ha tenido un producto extra -hotelero hasta posicionarse como un atractivo turístico integrado en las ofertas opcionales en el destino de Varadero. La evaluación incluye una valoración de los factores internos y del entorno que influyen en el desarrollo estratégico del producto. Un propósito fundamental del trabajo es demostrar la importancia de productos extra -hoteleros de esa naturaleza en el fortalecimiento del atractivo y la sostenibilidad del destino, más allá del conglomerado de instalaciones de alojamiento de alto estándar con un diseño inclusivo. En el trabajo se utilizan mapas cognitivos difusos para abordar el problema de por sí no estructurado y difícilmente cuantificable. Se recurre a las opiniones de expertos, incluidos los autores del trabajo
In situ hydration imaging study of a ye'elimite paste by ptychographic x-ray computed tomography
Eco-cements are a desirable alternative to ordinary Portland cements because of their lower CO2 footprints. For instance, the manufacture of Calcium SulfoAluminate (CSA) cements is more environmentally friendly than that of Portland cements as their production may decrease CO2 footprint by up to 40%. CSA cements contain ye'elimite, Ca4Al6O12SO4, as main phase. The hydration of ye'elimite leads to hydrated compounds such as crystalline ettringite (AFt), crystalline monosulfoaluminate (AFm) and amorphous aluminum hydroxide gel, Al(OH)3·nH2O.
Here, we report the results of a ptychographic X-ray computed tomography (PXCT) study on the in situ hydration of ye'elimite with gypsum at different early ages. PXCT is a nondestructive X-ray imaging technique which provides 3D electron density and attenuation coefficient distributions of cement pastes with an isotropic resolution close to 100 nm allowing distinguishing between component phases with very similar contrast in more conventional absorption-based X-ray tomography. The sample was prepared by hydrating ye'elimite with gypsum. Four datasets were recorded at 48, 53, 58 and 63 hours of hydration. The main aim of this imaging study was to quantify the microstructure evolution, within this time interval, with submicrometer spatial resolution. The different component phases were identified and their mass densities determined. Furthermore, the tomograms were segmented and the volume percentage of each component were determined and compared at the four hydrating ages.
The overall porosity content (air and pore solution) decreased from 11.5 to 8.8 vol% and the anhydrous material content (ye'elimite and gypsum) decreased from 14.7 to 7.5 vol% in the studied time interval. Correspondingly, the hydrated content (crystalline ettringite and aluminum hydroxide gel) increased from 73.7 to 83.7 vol%.
The time evolution of several anhydrous particles was analyzed to determine the dissolution rate of the ye'elimite particles. Similarly, the pore filling process has also been investigated by quantifying their time evolution. These rates are reported and some insights about the mechanisms of these processes are discussed.This work has been supported by MINECO through
BIA2014−57658-C2-1-R and BIA2014-57658-C2-2-R, which
is cofunded by FEDER, research grants. We thank SLS for
providing beamtime at the cSAXS beamline. We also thank the
Swiss National Science Foundation SNF for the support to the
work of J.C.d.S. (Grant 137772). Instrumentation development
was supported by SNF (R’EQUIP, No. 145056,“OMNY”) and
the Competence Centre for Materials Science and Technology
(CCMX) of the ETH-Board, Switzerland. In addition, the
authors would like to thank Dr. Manuel Guizar-Sicairos for his
valuable assistance with the ptychography and PXCT data
analysis
Nanoparticles engineered to bind cellular motors for efficient delivery
Background: Dynein is a cytoskeletal molecular motor protein that transports cellular cargoes along microtubules. Biomimetic synthetic peptides designed to bind dynein have been shown to acquire dynamic properties such as cell accumulation and active intra- and inter-cellular motion through cell-to-cell contacts and projections to distant cells. On the basis of these properties dynein-binding peptides could be used to functionalize nanoparticles for drug delivery applications. Results: Here, we show that gold nanoparticles modified with dynein-binding delivery sequences become mobile, powered by molecular motor proteins. Modified nanoparticles showed dynamic properties, such as travelling the cytosol, crossing intracellular barriers and shuttling the nuclear membrane. Furthermore, nanoparticles were transported from one cell to another through cell-to-cell contacts and quickly spread to distant cells through cell projections. Conclusions: The capacity of these motor-bound nanoparticles to spread to many cells and increasing cellular retention, thus avoiding losses and allowing lower dosage, could make them candidate carriers for drug delivery
Scavenging Behaviour of Red Deer Cervus elaphus Linnaeus, 1758 (Artiodactyla: Cervidae) in Eastern Spain
A male red deer was repeatedly observed scavenging in eastern Spain. This is the first time this behaviour of the red deer being recorded by means of camera traps. Scavenging behaviour of herbivores may have implications for wildlife biologists and managers
Development of biosensors for detection of SARS-CoV-2 virus by Triplex Enhanced Nucleic Acid Detection Assay (TENADA).
SARS-CoV-2, a positive-strand RNA virus has caused devastating effects. The standard method for COVID diagnosis is based on polymerase chain reaction (PCR). The method needs expensive reagents and equipment and well-trained personnel and takes a few hours to be completed. The search for faster solutions has led to the development of immunological assays based on antibodies that recognize the viral proteins that are faster and do not require any special equipment. Here we explore an innovative analytical approach based on the sandwich oligonucleotide hybridization which can be adapted to several biosensing devices. PolyPurine Reverse Hoogsteen hairpins (PPRHs) oligonucleotides that form high affinity triplexes with the polypyrimidine target sequences are used for the efficient capture of the viral genome. Then, a second labelled oligonucleotide is used to detect the formation of a trimolecular complex in a similar way than antigen tests do. The limit of detection is around 0.01 nM (a few femtomoles) without the use of any amplification steps. The Triplex Enhanced Nucleic Acid Detection Assay (TENADA) can be readily adapted for the detection of any pathogen requiring only the knowledge of the pathogen genome sequence
Hydration studies of ye’elimite by using Ptychographic X-ray nano-tomography
CSA (Calcium SulfoAluminate) cements may have variable compositions but all of them contain ye’elimite(Ca4Al6O12SO4). The manufacture of CSA cements is more environmentally friendly than that of ordinary Portland cements as their production releases up to 40% less CO2. The hydration of ye’elimite leads to crystalline ettringite (AFt) and amorphous aluminum hydroxide (AH3•nH2O).
Ptychographic X-ray computed nanotomography (PXCT) has been used here to study the hydration of ye’elimite-containing samples. PXCT is an X-ray imaging technique having demonstrated an isotropic 3D resolution better than 20 nm[1]. PXCT, which nondestructively provides 3D images of the sample complex-valued X-ray refractive index, has been recently applied for hydration studies of Portland cement samples[2].
Samples for this study were measured in cSAXS beamline (Swiss Light Source). The main goal of this study has been the quantification of the electron and mass densities of the phases present in these samples. These mass densities were compared with the theoretical values in order to identify the phases and matched well the expected values.
For instance, the hydration of pure ye’elimite with gypsum sample was studied. This sample should show a large amount of AFt due to the presence of gypsum in the hydration medium. This is precisely what it was observed from the analysis of the histogram. Figure 1 shows the tomogram of one slice obtained for this sample.
The most relevant results for CSA cement hydration will be discussed. A volume of interest (VOI) histogram has been studied in order to identify all the phases. Figure 2 shows a comparison between the histogram obtained in this study and a previous one performed by Gastaldi et al. (2012) at TOMCAT Beamline (Swiss Light Source). As it can be observed, TOMCAT data cannot properly distinguish between AFt and ye'elimite phase. Conversely, PXCT technique can resolve the peaks for all the phases present in CSA cements.
All reconstructions have been successful and now we are analyzing the data (segmentation, etc.) to characterize the porosities and the shape and size of the different phase, chiefly ettringite.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Quantitative analysis of cementitious materials by X-ray ptychographic nanotomography
Cement manufacturing is responsible for ~7% of the anthropogenic CO2 emissions and hence, decreasing the CO2 footprint, in a sustainable, safe, and cost-effective way, is a top priority. It is also key to develop more durable binders as the estimated world concrete stock is 315 Gt which currently results in ~0.3 Gt/yr of concrete demolition waste (CDW). Moreover, models under development predict a skyrocketing increase of CDW to 20–40 Gt/yr by 2100. This amount could not be easily reprocessed as aggregates for new concretes as such volumes would be more than two times the predicted need. Furthermore, concretes have very complex hierarchical microstructures. The largest components are coarse aggregates with dimensions bigger than a few centimetres and the smallest ones are amorphous components and the calcium silicate hydrate gel with nanoparticle sizes smaller than a few nanometres. To fully understand the properties of current and new cement binders and to optimize their performances, a sound description of their spatially-resolved contents is compulsory. However, there is not a tomographic technique that can cover the spatial range of heterogeneity and features of concretes and mortars. This can only be attained within a multitechnique approach overlapping the spatial scales in order to build an accurate picture of the different microstructural features. Here, we have employed far-field and near-field synchrotron X-ray ptychographic nanotomographies to gain a deeper insight into the submicrometer microstructures of Portland cement binders. With these techniques, the available fields of view range from 40 to 300 um with a true spatial resolution evolving between ~50to~300 nm. It is explicitly acknowledged here that other techniques like X-ray synchrotron microtomography are necessary to develop the whole picture accessing to larger fields of view albeit with poorer spatial resolution and without the quantitativeness in the reconstructed electron densities
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