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Abstract Background: There is a lack of knowledge about how persons with cerebral palsy (CP) perceive their ‘process of doing’ while performing everyday occupations. As described in the Model of the Process of Doing (MPoD), performing an occupation is a complex process consisting of six phases (generate idea, plan, initiate, enact, adjust, end) and time management. Aim: To collect the experiences of young adults with CP, classified at Manual Ability Classification System (MACS) level I or II, regarding how they perceive challenges in their occupational performance in relation to the different phases of the ‘process of doing’. Method: Semi-structured interviews were performed with ten participants with CP aged 19–30 years, MACS level I or II. The interview material was related to the MPoD phases using directed content analysis. Results: The participants’ descriptions of how they perceived their personal ‘process of doing’ showed problems in all MPoD phases. All participants experienced difficulties in one or more phases, but none had difficulties in all phases. Difficulties were more frequent in some phases than in others. Conclusion/Significance: To understand the complexity of doing everyday occupations in young adults with CP, there is a need to address all phases of the ‘process of doing’. [ABSTRACT FROM AUTHOR]

Landau phenomenological theory in combination with first-principles calculations was used to reveal the origin of the metamagnetic nature and the unusually strong dependence of the ordering temperature with doping of the Fe2P compound. We show that the magnetism of the two sublattices occupied by Fe atoms has an entwined codependency, which is strongly influenced by alloying. We furthermore demonstrate that a constrained disordered local moment approach combined with Monte Carlo simulations can only reproduce the experimental ordering temperatures in these technologically important prototype alloys for magnetocaloric refrigeration. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations and kinetic Monte Carlo simulations, we design a realistic and practical codoping technique for increasing the concentration of Mn atoms in GaAs and realizing high Curie temperatures in (Ga,Mn)As. We found that using codoping of Li interstitial atoms during the crystal growth has two great advantages. First, due to lower formation energy of Li interstitials compared to Mn interstitials, Li prevents formation of unwanted Mn interstitials. Second, Li interstitials can be removed by using post-growth annealing at low temperatures. This codoping method offers a general strategy to go far beyond the solubility limit and it should be applicable also to other diluted magnetic semiconductor systems. [ABSTRACT FROM AUTHOR]

Objective:To study whether the mode of delivery alters pain expression.Study Design:Full-term infants born by vaginal delivery or elective caesarean section were observed following high- and low-intensity pain stimuli, with recording of electrocardiogram, facial expression and vocalization.Result:Graded physiological and behavioral responses occurred, with greater responses to higher than lower intensity pain stimuli. Elevation in heart rate following both stimuli increased with time after vaginal delivery. Infants delivered by elective caesarean section showed stronger facial expressions and briefer time in vocalizations response to both interventions.Conclusion:Diminished responses following vaginal delivery suggest that physiological events associated with a normal delivery reduce the physiologic and sympathoadrenal activation by nociceptive mechanisms. Pain and stress reactivity appear to be inhibited during fetal life and sensory inputs during vaginal delivery may reverse this inhibition. To minimize neonatal pain, we recommend that postnatal invasive procedures to be performed shortly after vaginal birth.Journal of Perinatology (2009) 29, 44–50; doi:10.1038/jp.2008.129; published online 4 September 2008 [ABSTRACT FROM AUTHOR]

Aim: To investigate whether professional training and/or clinical experience affect the ability of caregiver to assess clinical signs of pre-emptive morphine analgesia. Methods: In the Neurological Outcomes & Pre-emptive Analgesia In Neonates trial preterm infants undergoing mechanical ventilation were randomized to receive continuous infusion, either of morphine or placebo blinded. Staff from centres in Sweden (Stockholm and Örebro) completed an assessment form. Results: A total of 360 assessment forms were collected from 52 neonates. In 59% of the cases, caregivers correctly identified patients group. Comparable proportion of answers were correct between physicians, nurses and assistant nurses (63, 60 and 54%, respectively, p = 0.60). Staff with Neonatal intensive care unit experience <1 year identified 63%, as compared to 65% for working 1–5 year, and 55% that has been working >5 years (p = 0.28). Staff's ability to correctly identify group assignment was reduced by amount of additional morphine (p < 0.01) and severity of illness (p = 0.01). Conclusions: Clinical medical staffs, including neonatologists, have great difficulties in assessing the presence and severity of pain. Further studies should focus on the methods for assessment of prolonged pain in preterm neonates, define the effects of adequate analgesia, and investigate the clinical factors that may alter neonatal responses to acute and prolonged pain. [ABSTRACT FROM AUTHOR]

Abstract: The structural and magnetic properties of a new ternary Ir–Mn–Ge phase, Mn3IrGe, as well as the solid solution Mn3Ir(Si1-xGex), , have been investigated by means of X-ray and neutron powder diffraction, magnetization measurements and first principles calculations. The crystal structure is cubic, of the AlAu4-type (an ordered form of the β-Mn structure), , space group P213, and the unit-cell dimension varies linearly with the silicon content. For all compositions, antiferromagnetic ordering is found below a critical temperature of about 225K. The magnetic structure is noncollinear, as a result of frustrated magnetic interactions on a triangular network of Mn atoms, on which the moments rotate 120° around the triangle axes. The magnitude of the magnetic moment at 10K is 3.39(4)μB for Mn3IrGe. The theoretical calculations reproduce with very good accuracy the magnitudes as well as the directions of the experimentally observed magnetic moments. [Copyright &y& Elsevier]

The strong coupling between the crystal structure and magnetic state (ferromagnetic or helical antiferromagnetic) of FeMnP0.75Si0.25 is investigated using density functional theory in combination with atomistic spin dynamics. We find many competing energy minima for drastically different ferromagnetic and noncollinear magnetic configurations. We also find that the appearance of a helical spin-spiral magnetic structure at finite temperature is strongly related to one of the crystal structures reported for this material. Shorter Fe-Fe distances are found to lead to a destabilized ferromagnetic coupling, while out-of-plane Mn-Mn exchange interactions become negative with the shortening of the interatomic distances along the c axis, implying an antiferromagnetic coupling for the nearest-neighbor Mn-Mn interactions. The impact of the local dynamical correlations is also discussed. [ABSTRACT FROM AUTHOR]

The electronic, thermodynamical, and transport properties of ordered Fe3X (X=Al,Si) alloys are studied from first principles. We present here a unified approach to the phase stability, the estimate of the Curie temperature, the temperature dependence of sublattice magnetizations, magnon spectra, the spin-stiffnesses, and residual resistivities. An important feature of the present study is that all calculated physical properties are determined in the framework of the same first-principles electronic structure model combined with the effective Ising and Heisenberg Hamiltonians used for study of the thermodynamical properties of alloys. Curie temperatures, spin-stiffnesses, and magnon spectra are determined using the same calculated exchange integrals. Finally, the transport properties are calculated using the linear-response theory. Our theoretical estimates compare well with available experimental data. In particular, calculations predict (in agreement with experiment) the ordered D03 phase as the ground-state alloy structure, demonstrate that a correct relation of Curie temperatures of Fe3Al/Fe3Si alloys can be obtained only by going beyond a simple mean-field approximation, provide reasonable estimates of spin-stiffnesses, and give resistivities compatible with structural disorder observed in the experiment. Although the calculated temperature dependences of the Fe magnetization on different sublattices are similar, they nevertheless deviate more than in the experiment, and we discuss a possible origin. [ABSTRACT FROM AUTHOR]

Di-iron phosphide (Fe2P) is a parent system for a set of magnetocaloric materials. Although the magnetic ordering temperature (Tc = 215 K) of the stoichiometric composition is too low for room-temperature magnetic refrigeration, the partial replacement of P with B, Si, or As elements results in a steep increase in the magnetic ordering temperature. Doping leads to different equilibrium volumes and hexagonal axial ratios (c/a) within the same crystallographic phase over a wide concentration range. Here, using first principles theory, we decompose the change in the total magnetic exchange interaction upon doping into chemical and structural contributions, the latter including the c/a-ratio and volume effects. We demonstrate that for the investigated alloys the structural effect can be ascribed mainly to the decrease in the c/a ratio that strengthens the magnetic exchange interactions between the two Fe sublattices. [ABSTRACT FROM AUTHOR]

Objective To study the effects of early versus delayed oxytocin augmentation on the obstetrical and neonatal outcome in nulliparous women with spontaneous but prolonged labour. Design Randomised controlled study. Setting Two delivery units in Sweden. Population Healthy nulliparous women with normal pregnancies, spontaneous onset of active labour, a cervical dilatation of 4–9 cm and no progress in cervical dilatation for 2 hours and for an additional hour if amniotomy was performed due to slow progress. Methods Women ( n = 630) were randomly allocated either to labour augmentation by oxytocin infusion (early oxytocin group) or to postponement of oxytocin augmentation for another 3 hours (expectant group). Main outcome measure Mode of delivery (spontaneous vaginal or instrumental vaginal delivery or caesarean section) and time from randomisation to delivery. Results The caesarean section rate was 29 of 314 (9%) in the early oxytocin group and 34 of 316 (11%) in the expectant group (OR 0.8, 95% CI 0.5–1.4), and instrumental vaginal delivery 54 of 314 (17%) in the early oxytocin versus 38 of 316 (12%) in the expectant group (OR 1.5, 95% CI 0.97–2.4). Early initiation of oxytocin resulted in a mean decrease of 85 minutes in the randomisation to delivery interval. Conclusion Early administration of oxytocin did not change the rate of caesarean section or instrumental vaginal delivery but shortened labour duration significantly in women with a 2-hour arrest in cervical dilatation. No other clear benefits or harms were seen between early and delayed administration of oxytocin. [ABSTRACT FROM AUTHOR]

Objective: To investigate the influence of morphine therapy and other factors on the attainment of full enteral feeds and on acquired gastrointestinal pathology in preterm infants. Design: Secondary data analysis from a randomised, placebo controlled trial. Setting: 16 neonatal intensive care units in USA, Sweden, France and UK. Patients: 898 infants (treatment group 449, control 449(. Gestation (median (range)): 27 (23—32( weeks; birth weight (median (range((: 985 (420—2440) g. Interventions: Morphine (M( or placebo (Pl) given preemptively by intravenous loading dose (100 μg/kg of morphine) and infusion (10—30 μg/kg/h depending on gestation) while infants were ventilated, for up to 14 days. "Open-label" morphine (A) could be given if clinically indicated. Main outcome measures: Age at full enteral feeds and major acquired gastrointestinal pathology. Results: The group randomised to morphine was later in attaining full feeds (median days (quartiles): M 20 (13—29(, Pl 17 (12—26(; p = 0.003(, and in starting feeds (median days (quartiles): M 5 (3—8), Pl 4 (2—7)(. In a linear regression model, age at full feeds was independently associated with birth weight, a score of neonatal morbidities, neonatal dexamethasone use and cumulative morphine dose. There was no relationship between morphine use and acquired gastrointestinal pathology (M 9/449, Pl 8/449; χ2 p = 0.81). Conclusions: Morphine delays the attainment of full enteral feeds, partly by delaying the start of feeding, but does not discernibly increase gastrointestinal complications. The attainment of full feeds is influenced by morphine dose, but other factors seem to be important, including birth weight and neonatal morbidity. [ABSTRACT FROM AUTHOR]

We show that the three most relevant magnetic properties (magnetic moment critical temperature, and interlayer exchange coupling) of metallic multilayers can be reproduced with good accuracy by first principles theory, provided that the picture of atomically sharp interfaces is abandoned and one allows instead for both interface alloying and interface roughness. The interface of a metallic multilayer (exemplified by the F/V System) is demonstrated to, at best, have interdiffusion essentially Over two to three atomic layers on each side Of the interface. Our conclusions are the result of combining experimental work with theoretical modeling, and we argue that this approach is the best avenue to obtain accurate information about the interface quality of metallic multilayers. [ABSTRACT FROM AUTHOR]

The half-metallic half-Heusler alloy NiMnSb is a promising candidate for applications in spintronic devices due to its low magnetic damping and its rich anisotropies. Here we use ferromagnetic resonance (FMR) measurements and calculations from first principles to investigate how the composition of the epitaxially grown NiMnSb influences the magnetodynamic properties of saturation magnetization Ms, Gilbert damping a, and exchange stiffness A. Ms and A are shown to have a maximum for stoichiometric composition, while the Gilbert damping is minimum. We find excellent quantitative agreement between theory and experiment for Ms and α. The calculated A shows the same trend as the experimental data but has a larger magnitude. In addition to the unique in-plane anisotropy of the material, these tunabilities of the magnetodynamic properties can be taken advantage of when employing NiMnSb films in magnonic devices. [ABSTRACT FROM AUTHOR]

The high Curie temperature multiferroic compound CuO has a quasidegenerate magnetic ground state that makes it prone to manipulation by the so-called "order-by-disorder" mechanism. First principle computations supplemented with Monte Carlo simulations and experiments show that isovalent doping allows us to stabilize the multiferroic phase in nonferroelectric regions of the pristine material phase diagram with experiments reaching a 250% widening of the ferroelectric temperature window with 5% of Zn doping. Our results allow us to validate the importance of a quasidegenerate ground state on promoting multiferroicity on CuO at high temperatures and open a path to the material engineering of multiferroic materials. In addition we present a complete explanation of the CuO phase diagram and a computation on the incommensurability in excellent agreement with experiment without free parameters. [ABSTRACT FROM AUTHOR]

During the Late Pleistocene, several possibly endemic cingulate species, known mostly from isolated osteoderms, cara-pace fragments, and caudal tubes, coexisted in the Brazilian Intertropical Region. Here, we describe the osteoderm micro- structure of Pachyarmatherium brasiliense, as well as the glyptodonts Panochthus greslebini, Panochthus jaguaribensis and Glyptotherium sp., in order to provide additional species-diagnostic characters and shed light on their evolutionary relationships. Pachyarmatherium brasiliense lacks several derived features shared by glyptodonts and pampatheres, such as extensive bone remodeling, fibers arranged in large bundles, and relatively poorly developed layers of compact bone, thus supporting its exclusion from glyptodonts as suggested by a recent cladistic study. The osteoderm histology of P. greslebini resembles that of other species of Panochthus (e.g., Panochthus frenzelianus). By contrast, the presence of relatively thick layers of compact bone, the configuration and size of resorption areas, the absence of randomly oriented lateral fiber bundles, and the absence of an intermediary region between the compact and trabecular bone potentially support the exclusion of Panochthus jaguaribensis from the genus. Finally, osteoderms of the Brazilian specimens of Glyptodontinae share histological features with Glyptotherium floridanus, rather than Glyptodon, thus reinforcing their assignment to Glyptotherium. These results highlight the relevance of histological osteoderm characters in cingulate systematics, ands call for further and more comprehensive studies. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the electronic structure and magnetic properties of III–V compound semiconductor based dilute magnetic semiconductors (DMS) from first-principles. The electronic structure of DMS is calculated by using the Korringa–Kohn–Rostoker coherent potential approximation (KKR-CPA) method in connection with the local density approximation (LDA). Describing the magnetic properties by a classical Heisenberg model, effective exchange interactions are calculated by applying magnetic force theorem for two impurities embedded in the CPA medium. With the calculated exchange interactions, T C is estimated by using the mean field approximation, the random phase approximation and the Monte Carlo simulation. In the above compounds, the magnetic interactions are well described from double exchange picture. Due to the short-range interactions, high-T C is difficult to achieve in the presently investigated materials. Based on the present results, two strategies towards high-T C are proposed to realize useful DMS materials. One uses spinodal decomposition to realize high blocking temperature in super-paramagnetic blocking phenomena and the other uses co-doping method to realize high concentration doping of magnetic impurities for high-T C. [Copyright &y& Elsevier]

In this work we examine critically the electronic structure of the rare-earth elements by use of the so-called Hubbard I approximation. From the theoretical side all measured features of both occupied and unoccupied states are reproduced, without significant deviations between observations and theory. We also examine cohesive properties like the equilibrium volume and bulk modulus, where we find, in general, a good agreement between theory and measurements. In addition, we have reproduced the spin and orbital moments of these elements as they are reflected from measurements of the saturation moment. We have also employed the Hubbard I approximation to extract the interatomic exchange parameters of an effective spin Hamiltonian for the heavy rare earths. We show that the Hubbard I approximation gives results which are consistent with calculations where 4f electrons are treated as core states for Gd. The latter approach was also used to address the series of the heavy/late rare earths. Via Monte Carlo simulations we obtained ordering temperatures which reproduce measurements within about 20%. We have further illustrated the accuracy of these exchange parameters by comparing measured and calculated magnetic configurations for the heavy rare earths and the magnon dispersion for Gd. The Hubbard I approximation is compared to other theories of the electronic structure, and we argue that it is superior. We discuss the relevance of our results in general and how this makes it possible to treat the electronic structure of materials containing rare-earth elements, such as permanent magnets, magnetostrictive compounds, photovoltaics, optical fibers, topological insulators, and molecular magnets. [ABSTRACT FROM AUTHOR]