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A systematic review of the literature was conducted to identify effective approaches to preventing and addressing abuse and neglect of older adults within health care settings in Canada. The review was conducted using databases searched from January 2000–April-May 2013. Additionally, expert panel members submitted article citations from personal archives. Two research associates (NRA) screened each title and abstract for inclusion. After inter-rater reliability was determined between the NRAs (Kappa score of 0.76), the records were divided, appraised, and data extracted independently. The review resulted in 62 studies that focused on identifying, assessing, and responding to abuse and neglect of older adults; education, prevention, and health promotion strategies; and organizational and system-level supports to prevent and respond to abuse and neglect. Abuse and neglect of older adults remains under-explored in terms of evidence-based studies; consequently, further research in all of the areas described in the results is needed.
Trauma during pregnancy poses a challenge in assessment and management due to its unique anatomical and physiological changes. Trauma is the leading non-obstetrical cause of death. There is paucity of epidemiological data in this subgroup in India. An emergency department (ED)-based epidemiological study was conducted.
Female trauma victims of reproductive age with both positive and negative urinary pregnancy tests (UPTs) were selected retrospectively. Documentation was done by the nursing staff from the ED case records. Mode, mechanism, severity, site of injury, and ED disposal time were noted, compiled, and analyzed.
Of 64 patients, 32 patients were UPT-positive and 32 were UPT-negative. The mean age was 26 (range 18–36) years. A total of 75% of UPT-positive and 59.3% of UPT-negative cases had assault due to domestic violence. As per START triage protocol, 84.3% of UPT-positive and 59.3% patients in UPT negative were triaged as yellow. Blunt trauma to the abdomen was the most common mechanism and site of injury in all patients. FAST and ultrasonic evaluation of the fetus was performed for all UPT-positive patients. The average ED disposal time was 2 hours 62 minutes in UPT-positive and 1.9 hours in UPT-negative.
Limited data suggest domestic violence as leading cause of trauma in pregnancy. A large, epidemiological study is required to validate this.
The pyramid of pain management involves sequential drug escalation but its role is limited in an emergency department (ED). The efficacy of parental opioid analgesics versus non-opioid analgesic in acute pain management of trauma victims in the ED was evaluated to formulate protocol.
All alert patients with a baseline visual analogue scale score (≥ 7) was randomly assigned either parental non-opioid (Group A) or opioid analgesics (Group B). The emergency care providers noted the VAS in either group at 15 minutes, 30 minutes, and 60 minutes, and at the time of discharge from the ED. If the patient's VAS score did not reduce by 50% at 30 minutes, repeat parental analgesics was given. The oral analgesics prescribed at the time of discharge were documented. Ethical clearance was taken. Data was compiled and analyzed.
Of 106 patients, 99 were analyzed. The mean age in Group A was 33.2 ± 13.2 years and 32.5 ± 18 years in Group B. The male:female ratio in Group A was 1.5:1 and 7:1 in Group B. The average baseline VAS score in Group A was 7.5, and that of Group B was 8.96. The average VAS at 15, 30, and 60 minutes and at discharge in Group A was 5.4, 5.34, 4.3, and 3.5 and it was 6.1, 6, 5.1, and 4.4. Repeat parental dose of analgesics were required in 95/99 (95%) patients in Group A and 5% that of Group B. The most common prescription at discharge from ED was non-opioid analgesics.
Acute pain relief was comparable in both groups. Non-opioid analgesics may be preferred over opioid in VAS score ± 7 in a busy emergency department for early disposition.
X-ray specular and off-specular reflectivity studies have been carried out to study the density modulations in liquids confined between two smooth silicon mirrors. The special technique as well as the advantages of using high energy and high brilliance synchrotron x-ray beams for carrying out such experiments will be discussed. Results will be presented on the ordering of octamethyl-cyclotetrasiloxane (OMCTS) as a function of the confining pressure, where we find evidence of layering as the gap is decreased from macroscopic down to a few nanometers.
Dielectric spectroscopy was applied to investigate the dynamic properties of liquid crystal octylcyanobiphenyl (8CB) confined in 2000 Å cylindrical pores of Anopore membranes with homeotropic and axial (planar) boundary conditions on the pore walls. Homeotropic boundary conditions allow the investigation of the librational mode in 8CB by dielectric spectroscopy. We found that the dynamics of the librational mode is totally different from the behavior observed in investigations of relaxation due to reorientation of molecules around their short axis. The interpretation of the temperature dependence of relaxation times and of the dielectric strength of the librational mode needs the involvement of the temperature dependence of orientational order parameter. For samples with axial boundary conditions, layers of LCs with different thickness were obtained on the pore walls as a result of controlled impregnation of porous matrices with 8CB from solutions of different liquid crystal concentration. The process due to rotation of molecules around their short axis with single relaxation time observed for bulk 8CB is replaced by a process with a distribution of relaxation times in thin layers. This relaxation process broadens with decreasing layer thickness.
We report on a study of the complex dielectric permittivity in polyaniline (PAN), poly-o-toluidine (POT) and poly-o-ethylaniline (OPEA) in the undoped and weakly doped state in the frequency range 1 mHz upto 1 MHz. The doping concentration defined as y=[C1-]/[N] was chosen so that 0 ≤ y ≤ 0.07. OPEA with y=0.50 was also investigated. The objective of this work was to investigate the contribution of the mobile charge defects (polarons and bipolarons) on the conductivity and dielectric relaxation at such low doping levels. The three samples were chosen so as to compare the effects of introducing larger interchain disorder while maintaining a similar conduction mechanism. In all samples studied we observe the presence of a dielectric relaxation mechanism and the relaxation times depend on the doping level and disorder. The presence of a larger number of polarons as the doping level is increased leads to multiple paths for the system to relax leading to progressively non Debye like relaxation process. The results are interpreted in terms of creation and annihilation of polarons and bipolarons and their subsequent diffusion.
The properties of thin films prepared by coevaporation of Y, Cu and Ba.F2, followed by post anneals in O2/H2O, are described. In particular, we emphasize what is known about. the relationship between the processing variables and the physical and chemical structure of the resulting films.
Using N2 adsorption (B.E.T.), small angle X-ray scattering and molecular adsorption (tiling) we attempt to describe the internal pore morphology and surface structure of three porous silica gels. The results are analyzed from both a classical euclidian and a fractal scaling viewpoint. The applicability of both viewpoints are shown to be limited but important in describing the structure of porous silicas.
Samples with the stoichiometry (CaxY1−x)Ba2Cu4O8, x = 0, 0.1 were synthesized at P(O2) = 25 and 200 bar. High Resolution TEM images for the samples synthesized at 25 bar show a high density of planar defects as compared to almost defect free microstructure of Ca0.1Y0.9Ba2Cu4O8 synthesized at 200 bar. The intragrain critical current density of the high defect density samples is however about 100 times lower that that of Ca0.1Y0.9Ba2Cu4O8 synthesized at P(O2) = 200 bar.
Small angle neutron scattering data of Vycor is analyzed using a chord distribution model describing the microporous structure. In addition, the same model is applied in interpreting the data taken when capillary condensation takes place in the porous medium. In both cases, the results are in good agreement with other measurements, and shows a promising potential in describing such a bicontinuous system.
The dynamics of surface fluctuations in thin supported polystyrene films have been investigated using x-ray photon correlation spectroscopy (XPCS) in reflection geometry. The results from the films thicker than four times of the radius of gyration (Rg) of polystyrene show the behavior of the capillary waves expected in viscous liquid. However, thinner films show a deviation indicating the need to account for viscoelasticity. Theoretical considerations with viscoelastic liquid model has been performed by introducing frequency dependent viscosity and compared with Fredrickson’s brush model (Macromolecules, 25, 2882 (1992)). The theory has been extended to the surface and interfacial modes in a bilayer film system. The results will be discussed in terms of surface tension, viscosity, and shear modulus.
The results of specular and diffuse x-ray scattering studies of multilayers are discussed. We show here that such studies can yield detailed statistical information about the interfacial roughness and morphology. Results on a GaAs/AlAs multilayer are presented and the data is analyzed within the Born approximation.
A knowledge of the structural behavior of molecules confined in thin liquid films and the way in which they differ from bulk behavior is of great importance to a variety of technological applications. We discuss X-ray scattering studies of the conformation of liquid polymer wetting layers on laterally structured substrates in order to test theories of the conformality of the wetting layer to the substrate. Recent work on guided X-ray beams confined to the thin film opens up the possibility of detailed studies of ordering phenomena in molecular layers adjacent to solid surfaces. Recent experiments are discussed.
We have investigated the dynamic behavior of liquid crystals (LC), which are not glass formers when in bulk form, confined in porous matrices with randomly oriented, interconnected pores as well as in parallel cylindrical pores with different pore sizes by photon correlation (time range: 20 ns-103s) and dielectric spectroscopies (frequencies: 0.1 Hz-1.5GHz). We observed that in random pores (pore size is 10 nm and 100 nm) LC does not crystallize at temperatures about 25° C below bulk crystallization temperature and the non-Debye relaxational processes studied by both photon correlation and dielectric experiments were found not to be frozen. Slow relaxational process which does not exist in bulk LC and a broad spectrum of relaxation times (10−8 − 10)s appear not only for LC in random pores but in cylindrical pores as well. However in matrices with random pores of 100 Å, glass-like behavior of slow mode (τ > 1ms) was observed. The relaxation time (determined in photon correlation experiment) of this slow process strongly increases when temperature decreases from 300 K up to 270 K varying from 0.2ms to 14 s and it's temperature dependence is described by the Vogel-Fulcher law.
Porous matrices with determined pore size, volume fraction and structure can be used as model systems to understand physical properties of dispersed liquid crystals (LC) - material important for different applications. Using photon correlation spectroscopy and dielectric spectroscopy we investigated dynamic properties of nematic liquid crystal dispersed in porous matrices with randomly oriented, interconnected pores (porous glasses with average pore sizes of 100 Å and 1000 Å) and parallel cylindrical pores (Anopore membranes with pore diameters of 200 Å and 2000 Å). Since the structural characteristics of these matrices are nearly independent of the temperature, all observable effects due to temperature changes can be attributed to the change in the physical properties of the second component (bC). The spatial confinement and a highly developed interface in porous matrices have a strong influence on the optical and dielectric properties of confined LC which is resulted in: appearance of at least two new dielectrically active modes, absent in the bulk and existence of slow glass-like relaxational process detected in both dielectric and photon correlation experiments.
An effective way of preparing a variety of liquid crystal based nanocomposite materials is to disperse LC in porous media with different porous matrix structure, pore size and shape. We present the results of investigations of quasiequilibrium and dynamical properties of nematic and smectic liquid crystals (LC) dispersed in porous matrices with randomly oriented, interconnected pores (porous glasses) and parallel cylindrical pores (Anopore membranes) by light scattering, photon correlation and dielectric spectroscopies. Confining LC to nanoscale level leads to quantitative changes in physical properties and appearance of new behavior which does not exist in either of the components. Relaxation of director fluctuations which is characterized by single relaxation time in the bulk LC are transformed to a process with a spectrum of relaxation times in pores, which includes extremely slow dynamics typical for glass formers. Existence of developed interface in these materials leads to new dielectric properties such as an appearance of a low frequency relaxation of the polarization and modification of dipole rotation.
Heterogeneous microcomposite materials based on porous matrices with randomly oriented, interconnected pores (porous glasses with average pore sizes of 100 Å and 1000 Å) and parallel cylindrical pores (Anopore membranes with pore diameters of 200 Å and 2000 Å) impregnated with liquid crystals (LC) were investigated by dynamic light scattering and dielectric spectroscopy. The physical properties of confined LC are very different from that of the bulk. One of the new properties among others observed for LC confined in porous matrices is the slow relaxational process which does not exist in the bulk LC and a wide spectrum of relaxation times (10−8 – 10)s which were established in both dynamic light scattering and dielectric experiments. We found that for LC dispersed in porous matrices with randomly distributed interconnected pores, the contribution to physical properties and observed behavior from interfacial layers dominates and almost completely determines low frequency relaxational process.