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The conducting state of a quasi-two-dimensional electron gas (q2DEG), formed at the heterointerface between the two wide-bandgap insulators LaAlO₃ (LAO) and SrTiO₃, can be made completely insulating by low-energy, 150-eV, Ar⁺ irradiation. The metallic behavior of the interface can be recovered by high-temperature oxygen annealing. The electrical transport properties of the recovered q2DEG are exactly the same as before the irradiation. Microstructural investigations confirm that the transition is not due to physical etching or crystal lattice distortion of the LAO film below its critical thickness. They also reveal a correlation between electrical state, LAO film surface amorphization, and argon ion implantation. The experimental results are in agreement with density functional theory calculations of Ar implantation and migration in the LAO film. This suggests that the metal-insulator transition may be caused by charge trapping in the defect amorphous layer created during the ion irradiation.

Background:\ud The main role of pretreatment is to reduce the natural biomass recalcitrance and thus enhance sac-\ud charification yield. A further prerequisite for efficient utilization of all biomass components is their efficient fractiona-\ud tion into well-defined process streams. Currently available pretreatment methods only partially fulfill these criteria. \ud Steam explosion, for example, excels as a pretreatment method but has limited potential for fractionation, whereas \ud organosolv is excellent for delignification but offers poor biomass deconstruction.\ud Results:\ud In this article, a hybrid method combining the cooking and fractionation of conventional organosolv pre\ud -\ud treatment with the implementation of an explosive discharge of the cooking mixture at the end of pretreatment was \ud developed. The effects of various pretreatment parameters (ethanol content, duration, and addition of sulfuric acid) \ud were evaluated. Pretreatment of birch at 200\ud °C with 60%\ud v/v ethanol and 1%\ud w/w\ud biomass\ud H\ud 2\ud SO\ud 4\ud was proven to be the \ud most efficient pretreatment condition yielding pretreated solids with 77.9%\ud w/w cellulose, 8.9%\ud w/w hemicellulose, \ud and 7.0\ud w/w lignin content. Under these conditions, high delignification of 86.2% was demonstrated. The recovered \ud lignin was of high purity, with cellulose and hemicellulose contents not exceeding 0.31 and 3.25%\ud w/w, respectively, \ud and ash to be

Background: Emotional distress (depression and anxiety) has been known to affect mortality after a myocardial infarction (MI). One possible mechanism is through medication non-adherence. Few studies have investigated the link between statin adherence and emotional distress, and results are not consistent. We aimed to explore whether emotional distress affects adherence among first-time MI patients younger than 75 years old receiving a prescription for the first time. Methods: We identified first-MI individuals younger than 75 years from the SWEDEHEART national quality registers discharged with a statin prescription. The main exposure was the anxiety/depression portion of the EQ-5D from Interview 1 (6-10 weeks post -MI) and Interview 2 (12-14 months post -MI). We calculated adherence from the Swedish Prescribed Drugs Register during three observation periods (OP): [1] Interview 1 to Interview 2, [2] one year post Interview 2, and [3] two years post Interview 1. Results: Emotional distress at Interview 1 was not associated with statin adherence for OP1 (RR: 0.99, 95% CI: 0.98, 1.01). Emotional distress at Interview 2 was associated with lower adherence one year later (RR: 0.95, 95% CI: 0.93, 0.98). Emotional distress at Interview 1 was associated with a small decrease in adherence in the complete OP for adherence (RR: 0.98, 95% CI: 0.96, 0.99). Conclusion: Emotional distress was marginally, but independently, associated with lower adherence to statin two years after the MI. Our study suggests that emotional distress may be an important factor for long-term statin adherence, and, thus, may play a clinically important role in long-term outcome.

We show that less than 10% of the barrier area dominates the electron tunneling in state-of-art Al/AlOx/Al Josephson junctions. They have been studied by transmission electron microscopy, specifically using atomic resolution annular dark field (ADF) scanning transmission electron microscopy (STEM) imaging. The direct observation of the local barrier thickness shows a Gaussian distribution of the barrier thickness variation along the junction, from ~1 nm to ~2 nm in the three junctions we studied. We have investigated how the thickness distribution varies with oxygen pressure (po) and oxidation time (to) and we find, in agreement with resistance measurements on similar junctions, that an increased to gives a thicker barrier than an increased po., Comment: 5 pages, 4 figures, 1 table

Background: Both patients suffering from schizophrenia and patients suffering from recurring mood disorder show cognitive impairments as established by a variety of neuropsychological tests. The aim of the present study was to investigate the neuropsychological performance of euthymic patients who had recurring mood disorder and the possible relationship between episodes of hospitalization and cognitive impairments. Method: Twenty-six euthymic patients with a DSM-III-R recurring mood disorder diagnosis were investigated by using the Synonym Reasoning and Block-Test Battery and a part of the Halstead-Reitan Test Battery. Results: An overall lowered performance in the test results was found. There was a significant positive relationship between four different tests and the number of hospitalization episodes; the patients with impaired cognitive functioning had significantly more hospitalization episodes than patients with normal cognitive functioning. Conclusion: The results suggest that a subgroup of patients with recurring mood disorder are defined by more relapses and episodes of hospitalization and show cognitive dysfunctions even when euthymic.

Contains fulltext : 112105.pdf (Publisher’s version ) (Closed access) In times of crisis, international organizations (IOs) are often called upon for help. Such crises may have both domestic and transnational features. In 2012 the domestic revolt in Syria, which had started the previous year, escalated and the United Nations (UN) was asked to help work towards a permanent solution. When in 2011 the situation in Somalia caused the population to flee across the border, the UN High Commissioner for Refugees (UNHCR) was instrumental in providing shelter and food for those in need. Another example is the involvement since 2008 of the European Union (EU), the International Monetary Fund (IMF) and the European Central Bank (ECB) in trying to solve the ongoing European sovereign debt crisis. The involvement of IOs in times of crisis comes as no surprise, since IOs are usually founded to meet trans-border problems. Many governments, but also public opinion and civil society actors, therefore naturally turn to IOs for solutions, all the more so when a situation occurs for which no obvious intergovernmental, i.e. exclusively between states, solution seems within reach.

The observation of a two dimensional electron gas (2DEG) (1, 2), superconductivity (3, 4), magnetic effects (5) and electronic phase separation (6-8) at the interfaces of insulating oxides, especially LaAlO3/SrTiO3, has further enhanced the potential of complex oxides for novel electronics. The occurrence of the 2DEG is strongly believed to be driven by the polarization discontinuity (9) at the interface between the two oxides. In this scenario, the crystal orientation plays an important role and no conductivity would be expected for e.g., the interface between LaAlO3 and (110)-oriented SrTiO3, which should not have a polarization discontinuity (10, 11). Here, we report the observation of unexpected conductivity at the LaAlO3/SrTiO3 interface prepared on (110)-oriented SrTiO3. The conductivity was further found to be strongly anisotropic, with the ratio of the conductance along the different directions parallel to the substrate surface showing a remarkable dependence on the oxygen pressure during deposition. The conductance and its anisotropy are discussed based on the atomic structure at the interface, as revealed by Scanning Transmission Electron Microscopy (STEM) and further supported by density functional theory (DFT) calculations., Comment: 17 pages, 5 figures

Twenty-five patients with fractures of the lower leg treated by closed reduction and plaster fixation were examined an average of 7 years and 8 months after trauma. The end result was assessed according to the following: (1) The patient's own opinion; (2) clinical examination including comparing range of motion in knee and ankle in the fractured and non-fractured leg, leg length discrepancy, malrotation of the injured extremity and muscle force analysis; (3) radiological examination. All fractures had healed after a mean of 13.4 weeks. Twelve of the 25 patients had no complaints. Subjective and objective assessment of the end results were in good correlation. Only eight patients had remaining radiological displacement, in only one of which it was severe. The slight remaining malpositionings did not influence the final functional result. The muscle force analysis showed that fractures caused by high-energy trauma also brought permanent reduction of muscular strength to the fractured extremity.

Superconducting behavior has been observed in the Sr2RuO4-Sr3Ru2O7 eutectic system as grown by the flux-feeding floating zone technique. A supercurrent flows across a single interface between Sr2RuO4 and Sr3Ru2O7 areas at distances that are far beyond those expected in a conventional proximity scenario. The current-voltage characteristics within the Sr3Ru2O7 macrodomain, as extracted from the eutectic, exhibit signatures of superconductivity in the bilayered ruthenate. Detailed microstructural, morphological and compositional analyses address issues on the concentration and the size of Sr2RuO4 inclusions within the Sr3Ru2O7 matrix. We speculate on the possibility of inhomogeneous superconductivity in the eutectic Sr3Ru2O7 and exotic pairing induced by the Sr2RuO4 inclusions., Comment: Pages 4, figures 3, submitted to Phys. Rev. Lett

The study of tensor correlations and pions in dense matter in astronomical contexts has recently acquired renewed importance for a number of reasons. One is the discovery by Akmal, and Pandharipande (Phys. Rev. C56 2261 (1997)) of a striking increase in tensor correlations in cold matter at densities not far above that of isospin-symmetric nuclear matter at saturation. A second is that, according to a calculation by Mayle and Wilson, softening of the equation of state by the appearance of thermal pions can play an important role. A third is that the strength of tensor correlations is a crucial ingredient in calculating rates of neutrino emission and scattering, which are needed in calculations of stellar collapse and of the cooling of neutron stars. We describe some recent results for the response of nuclear matter when tensor interactions are taken into account, and indicate some unresolved issues., Comment: 8 pages, 1 figure. Talk presented by C.J.P. at "Compact Stars in the QCD Phase Diagram" held in Copenhagen (NORDITA and Niels Bohr Institute), 15 - 18 Aug. 2001

Magnetization and magnetoresistivity studies of Fe/V (001) superlattices are reported. The first giant magnetoresistance peak with respect to the vanadium and iron layer thicknesses is investigated. The interlayer antiferromagnetic coupling strength is found to show a peak at a vanadium layer thickness of 13 atomic monolayers ($\approx$ 20 \AA) with a full width at half maximum of about 2 monolayers. The antiferromagnetic coupling shows a maximum at an iron layer thickness of about 6 monolayers ($\approx$ 9 \AA) for series of superlattices with vanadium thicknesses around 13 monolayers. The magnitude of the giant magnetoresistance shows a similar variation as the antiferromagnetic coupling strength., Comment: REVTeX 4 style; 8 pages, 7 figures. The TEM picture (Fig. 3) is also included in GIF format (TEM.gif)

Although more than 30 years have passed since the introduction of scintigraphic testing of gastric emptying there has been no well-defined standard. Eight Swedish hospitals have established a nationally standardized method for scintigraphic testing of gastric emptying of solids. 160 healthy subjects participated. The meal consisted of a 99mTc-labeled omelet (1300 kJ) and 150 ml unlabeled soft drink (290 kJ). There were no differences in calculated variables between the centers. Premenopausal women showed slower emptying than postmenopausals and men of any age, making separate reference values for younger women necessary.

Abundance analysis of carbon has been performed in a sample of 80 late F and early G type dwarf stars in the metallicity range -1.06 < [Fe/H] < 0.26 using the forbidden [C I] line at 8727 A. This line is presumably less sensitive to temperature, atmospheric structure and departures from LTE than alternative carbon criteria. We find that [C/Fe] decreases slowly with increasing [Fe/H] with an overall slope of -0.17 +- 0.03. Our results are consistent with carbon enrichment by superwinds of metal-rich massive stars but inconsistent with a main origin of carbon in low-mass stars. This follows in particular from a comparison between the relation of [C/O] with metallicity for the Galactic stars and the corresponding relation observed for dwarf irregular galaxies. The significance of intermediate-mass stars for the production of carbon in the Galaxy is still somewhat unclear., 14 pages including 10 Postscript figures, Uses l-aa.sty, Accepted for publication in Astronomy & Astrophysics, Complete Postscript file available at ftp://ftp.astro.uu.se/pub/articles/atmos/P133

Tl-2212 thin films were grown ex situ in a two step process on a variety of substrates, including ones with artificially introduced high angle steps. Grain boundary weak links were formed on LaAlO3 substrates with steps and on bicrystal substrates and were employed in dc SQUIDs. The white noise level of the SQUIDs was 50 mu Phi(0)/root Hz at 77 K. A 12.5 GHz HEMT oscillator stabilized with a Tl-2212 resonator gave 8-10 dB lower phase noise than using a gold resonator.

A medical application is a highly complex system that embraces many data types and a very large number of data processing functions and methods. The development of integrated software engineering environments has deeply changed the conception of applications and the profile of the application developers. In this paper, we address the problem of the development process of a specific multimedia application, called ARTEMIS, within the distributed HELIOS environment. The application is intended to manage information about hypertensive patients, in particular, retrieval and display of administrative, clinical and biological data and display and analysis of digital angiography images and medical reports. The objective is to show how the developer can use, customize and organize the services HELIOS provides. A particular focus is set on reuse strategies and integration during the development process. A scenario has been realized and illustrates the current state of the application. The discussion focuses on the advantages of such distributed environments in medical application development.

Between 1982 and 1985, 23 Kessel total shoulder arthroplasties were performed on 22 patients. A clinical and roentgenographic review was performed by an independent observer. Three patients had their prostheses removed and three had revision surgery, leaving 17 shoulders in 16 patients available for study, all with rheumatoid arthritis (RA). All patients were relieved of pain and noticed a general improvement in activities of daily living. Passive flexion and rotation were increased, but active movements remained unchanged. Roentgenographically, radiolucent zones developed around the scapular component on all patients within one year but only around one of the humeral components. Total shoulder arthroplasties with the Kessel prosthesis in RA relieved pain and improved shoulder and arm function. The long-term results were complicated by a high incidence of loosening of the glenoid component, probably a feature of the constrained design of the Kessel prosthesis.

It has been shown in a number of studies that the Kalina cycle can have considerably higher efficiencies than the Rankine cycle. An especially advantageous application is as a bottoming cycle to a gas turbine. In this paper a gas turbine topping cycle has been assumed. Three different configurations of the Kalina bottoming cycle have been examined and compared. One is an original cycle (El-Sayed and Tribus, 1985) with a flash separator. In another configuration, a second feedwater heater is added and in a third a distillation column instead of a flash separator is used. The stages of the column are heated by exchanging heat with two different streams in the Kalina distillation condensation subsystem. For each configuration, the different compositions in the cycle have been varied. The First Law efficiency and the exergetic efficiency have been calculated as well as the rate of exergy loss in each unit. The results show that the cases with the best performance of each of the three configurations differ very little in efficiency. The original cycle has the highest efficiency for the conditions studied.

Titanium oxide films were prepd. by reactive DC magnetron sputtering onto SnO2:F coated glass substrates. The O2/Ar gas flow ratio was kept at a const. value Γ during the deposition, and a series of films were deposited with 0.050

Crosslinked hydrogels of poly(acrylic acid) neutralized with calcium hydroxide were synthesized using free radical co-polymerization. The effects of the amount added calcium on the elastic modulus and swelling properties of the gels and the correlation to phase behaviour and structural changes within the gels were studied using texture analysis, gravimetric analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and atomic force microscopy (AFM). It was found that the elastic modulus decreased nonlinearly with increasing amount of added calcium and that the swelling’s dependence on the amount of added calcium was complicated. The maximum swelling increased with increasing amount of added calcium until a critical calcium content was reached, upon which the gels phase separated, with a strong decrease in swelling as a result. The changes in properties are explained by the fact that calcium affects the structure of the polymer network during synthesis and by the phase behaviour of the gels. Changes in the gel structure with the addition of calcium were detected with AFM. Furthermore, AFM revealed different phases on the nanometre scale for the sample with a calcium content around which phase separation is macroscopically observed. Finally, it was shown that the sulphur from the initiator potassium persulfate formed crystal like regions with high sulphur and calcium content upon drying of the hydrogels.