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La selección de la fórmula más adecuada en nutrición enteral domiciliaria a largo plazo es un tema controvertido. Nuestro objetivo fue estudiar una fórmula hipercalórica hiperproteica en pacientes con alimentación exclusivamente con sonda a largo plazo (180 días).

The selection of the most appropriate formula in long-term home enteral nutrition is a controversial issue. Our objective was to study a high protein hypercaloric enteral nutrition formula in patients with long-term feeding (180 days).

A solid-state 1H magic-angle spinning (MAS) NMR method is described to characterize the internal pore spaces and the external void spaces of powdered mesoporous solids containing surface OH groups. This method is based on fast proton exchange between homogeneously distributed surface OH groups of the porous hosts and added guests containing exchangeable NH protons. The position of the coalesced NH/OH signal in a given local space depends on its surface/volume ratio (S/V). In the case of slow guest exchange between spaces with different S/Vratios, coalesced signals are observed for each space where the relative signal intensities reflect the mole fractions of the guests in the different spaces. This method was tested by performing 1H MAS NMR experiments on the samples of liquid 4-methyl-1H-pyrazole (MPz) embedded in mesoporous silica of the MCM-41 type (2.9 nm pore diameter) and the SBA-15 type (8.9 nm pore diameter). To guarantee fast NH/OH proton exchange, the experiments were performed at 398 K well below the boiling point. Three distinct signals were observed for MPz assigned to (i) the internal cylindrical pores, (ii) the external interstitial void space between the packed particles, and (iii) the space outside the powdered solid containing neat liquid MPz. From the NMR data analysis, surface/volume ratios are derived for the internal pores, which agree well with those obtained with a simple geometrical model after applying a surface-roughness correction. In addition, S/Vratios for the external space, as well as internal surface/external surface (S/S) and internal volume/external volume (V/V) ratios, are derived. It is shown that at low filling fractions, MPz preferentially enters the internal pores, but at larger fractions, MPz enters the external spaces. Moreover, it is shown that the final internal pore NH/OH ratio is achieved before the pores are filled. A scenario that rationalizes these findings in connection with the hydrogen-bonded states of MPz is presented where the number and the hydrogen-bonded state of guest molecules in a given pore are discussed.

Age is one of the principal risk factors for development of frailty fractures. Age pyramids show a population that is becoming increasingly more elderly, with an increasing incidence of fractures, and the forecasts for the future are truly alarming. Adequate handling of these patients who are especially at risk, at both the preventive and care levels, with a well-defined orthogeriatric model is necessary to respond to this clinical challenge. The objective of this review is to analyze the efficacy of the different strategies for the handling of geriatric patients with fracture risk.

Describir los factores predictivos de mortalidad de los pacientes muy añosos que acuden a urgencias por infección y requieren ingreso.

El objetivo de este trabajo es describir las características de los pacientes con fractura de cadera en los hospitales públicos de Castilla y León recogidos durante un periodo de tiempo de 3 meses (noviembre del 2014 y octubre y noviembre del 2015).

To achieve a more exact understanding of the water transport in natural channels, a series of non-natural structures have been developed. They have been studied by far-infrared spectroscopy, solid-state nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis, and variable-temperature powder X-ray diffraction to examine the behavior of water at the molecular level. Water in these predominantly nonpolar pores can be metastable, with filling and emptying occurring upon changes in solvent conditions. The water contained in these pores exhibits a dynamics that might be controlled, since it depends on the structural features of the monomers that form the pore “skeleton”. We have observed changes in the pore diameter depending on the selected isomer. This provokes at a given temperature differences in the arrangement and dynamics of the contained water. The water dynamics increases with both temperature and pore diameter in a process that is reversible over a temperature range specific for each structure. Beyond this particular temperature threshold, the pore water can be irreversibly evacuated, and at this point a decrease of the dynamics is observed. The slower dynamics of the remaining water in partially evacuated pores is probably due to the increased interaction with the inner-pore surface owing to a concomitant narrowing of the pore. These findings not only highlight the need for the presence of freely moving water inside the pore to sustain its permeability by water, but also point to the decrease in the dynamics of the remaining water in partially evacuated pores.

We have studied the properties of a series of solid hydrated organic porous networks with pore diameters ranging from approximately 0.4 to 0.9 nm using the attenuated total reflection infrared (ATR-IR) technique. These subnanometer organic pores are composed of water and of organic racemic bicyclic monomers containing carboxylic, alcoholic, ether functions and different appendices. In particular, the doubly hydrated hydroxyl acids 12H2O and 22H2O form cylindrical pores in which half of the water molecules are part of the walls and the other half are located inside the pores. In a first step, by a comparison of the spectra of a family of related compounds, the COOH, COH as well as the wall and pore water stretches were assigned. The COOH bands are broad and red-shifted as compared to carboxylic acid dimers, and exhibit a substructure assigned to Fermi resonances. The OH stretches fulfill well Novak’s correlation with the corresponding crystallographic O...O distances. In a second step, we have followed the deuteration of the different functional groups of solid 22H2O by ATR-IR by heavy water vapor. Surprisingly, we observe that the rates of deuteration are the same for all functional groups although exhibiting biexponential time dependence, in contrast to the liquid state where COOH groups exchange protons with water much faster than with alcohols. This result is rationalized in terms of slowly diffusing lattice defects resembling a local liquid or glass in the subnano scale in which the different exchange reactions take place. The nonexponential deuteration is explained in terms of a faster deuteration of crystal surface layers.

A comparative scanning tunneling microscopy study of the behavior of chemically very similar amphiphilic compounds on Au surfaces is performed. It has been possible to relate different tendencies on a Au(111) single crystal surface to the distinct crystalline supramolecular structures to which the compounds give rise in the solid state. Moreover, the supramolecular hexameric ring that structures the crystal structure of one of the compounds could be identified on the Au surface. This technique has allowed us to obtain a qualitative picture of the aggregation states in solution previous to the nucleation. For the family of the studied compounds, it thus provides information about the likelihood of self-assembling in a particular way in the solid state.

The article discusses a study on the hiring and retaining of great independent school teachers in the U.S. Topics covered include how the study found that independent schools use four important characteristics to describe high-quality teachers which are strong relationship with students, strong pedagogical knowledge and content expertise, a growth mindset about their own capacity, and fits well within the school's culture.