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The major challenge for the development of spin based information processing is to obtain efficient ways of controlling spin. Here, Michiardi et al show that the Rashba spin-splitting at the surface of Bi2Se3 topological insulator can be controlled via optical pulses on picosecond timescales.

The microscopic picture of how superconductivity is linked to antiferromagnetic order in Fe-based compounds remains elusive. Here, Mannaet al. report superconducting correlations which spatially coexist with bi-collinear antiferromagnetic order in a one unit cell thin layer of FeTe grown on Bi2Te3.

Phase pure samples of the half-Heusler material TiCoSb were synthesised and investigated. Multi-temperature synchrotron powder X-ray diffraction (PXRD) data measured between 90 and 1000 K in atmospheric air confirm the phase purity, but they also reveal a decomposition reaction starting at around 750 K. This affects the high temperature properties since TiCoSb is semiconducting, whereas CoSb is metallic. Between 90 K and 300 K the linear thermal expansion coefficient is estimated to be 10.5 × 10−6K−1, while it is 8.49 10−6K−1between 550 K and 1000 K. A fit of a Debye model to the Atomic Displacement Parameters obtained from Rietveld refinement of the PXRD data gives a Debye temperature of 395(4) K. The heat capacity was measured between 2 K and 300 K and a Debye temperature of 375(5) K was obtained from modelling of the data. Coming from low temperatures the electrical resistivity shows a metallic to semiconducting transition at 113 K. A relatively high Seebeck coefficient of ∼−250 μV K−1was found at 400 K, but the substantial thermal conductivity (∼10 W mK−1at 400 K) leads to a moderate thermoelectric figure of merit of 0.025 at 400 K. [ABSTRACT FROM AUTHOR]

Three Ba8Al16Ge30clathrate type I samples have been prepared using three different synthesis methods; flux growth, Czochralski growth, and stoichiometric mixing. The samples were characterized by X-ray powder diffraction, multi-temperature single-crystal X-ray diffraction, high-resolution low-temperature (20 K) single-crystal neutron diffraction, and measurement of transport properties. The samples show a remarkable variation in the aluminum/germanium occupancies on the host-structure sites and minor variation in the total aluminum content. The observed occupancy variation forms the basis for the formulation of a set of simple rules for the maximum site occupancy factors of trivalent elements in the host structure. The rules provide an explanation for why the overwhelming majority of clathrate samples containing trivalent elements are n-type rather than p-type. The nuclear density of the barium guest atom in the large cage is calculated from the neutron diffraction data, and it is found to be strongly dependent on the host structure and the exact aluminum siting. Thus, the sample with low aluminum content has a prolate-shaped barium nuclear density, whereas a higher aluminum content leads to the well-known torus shape observed in other clathrates. This demonstrates that the host−guest interactions are not merely ionic and that they significantly influence the guest-atom structure and dynamics. Comparison of derived Einstein temperatures and bond distances for the three samples reveals that the compound with the highest aluminum content (flux growth) has the strongest host−guest interaction, even though it also has the largest unit cell. Again, the specific properties of the guest atoms are not only determined by the clathrate cage size but also by the subtle chemical interactions between the host structure and the guest. The thermal conductivity is about 3 times smaller for the stoichiometric sample than for the Czochralski-pulled sample. Thus, control of the host-structure chemistry is not only a key to manipulating the electrical properties of clathrates but also the thermal conductivity. [ABSTRACT FROM AUTHOR]

Surgical anaesthesia with haemodynamic stability and opioid-free analgesia in fragile patients can theoretically be provided with lumbosacral plexus blockade. We compared a novel ultrasound-guided suprasacral technique for blockade of the lumbar plexus and the lumbosacral trunk with ultrasound-guided blockade of the lumbar plexus. The objective was to investigate whether the suprasacral technique is equally effective for anaesthesia of the terminal lumbar plexus nerves compared with a lumbar plexus block, and more effective for anaesthesia of the lumbosacral trunk. Twenty volunteers were included in a randomised crossover trial comparing the new suprasacral with a lumbar plexus block. The primary outcome was sensory dermatome anaesthesia of L2-S1. Secondary outcomes were peri-neural analgesic spread estimated with magnetic resonance imaging, sensory blockade of dermatomes L2-S3, motor blockade, volunteer discomfort, arterial blood pressure change, block performance time, lidocaine pharmacokinetics and complications. Only one volunteer in the suprasacral group had sensory blockade of all dermatomes L2-S1. Epidural spread was verified by magnetic resonance imaging in seven of the 34 trials (two suprasacral and five lumbar plexus blocks). Success rates of the sensory and motor blockade were 88-100% for the major lumbar plexus nerves with the suprasacral technique, and 59-88% with the lumbar plexus block (p > 0.05). Success rate of motor blockade was 50% for the lumbosacral trunk with the suprasacral technique and zero with the lumbar plexus block (p < 0.05). Both techniques are effective for blockade of the terminal nerves of the lumbar plexus. The suprasacral parallel shift technique is 50% effective for blockade of the lumbosacral trunk., (© 2014 The Association of Anaesthetists of Great Britain and Ireland.)

The impact of influenza on work absenteeism is poorly documented. We used data from the national registry and Norway Post AS (>14,000 employees) to explore sickness absence patterns from 2005/06 through 2009/10 in Norway. Annually, an estimated 2.868% (mean 95% confidence interval (CI): 2.405-4.820%) of the working population obtained sick leave for influenza, of whom 0.915% (mean 95% CI: 0.453-1.590%) had diagnoses for other respiratory illnesses with influenza as underlying cause. In the 2009/10 pandemic season, the absence rate increased 1.5-fold, mainly due to a 73% increase in influenza-diagnosed sick leaves. At Norway Post AS, absence related to seasonal influenza accounted for 0.351% (mean 95% CI: 0.126-0.704%) of total person-days annually (excluding parental care absence), of which 32-43% were estimated to be self-certified. Medically certified sick leave increased 1.3-fold in the pandemic season to 0.458% (95% CI: 0.176-0.856), while self-certified sick leave remained at a level typical for seasonal influenza. We found a significant four-fold increase in work loss to care for sick children, 0.048% (95% CI: 0.031-0.070%) of person-days, compared with 0.012% (95% CI: 0.004-0.028%) in 2008/09. In conclusion, GP-certified and parental care work absence were higher in the pandemic season. More studies are needed to quantify the burden of self-certified sick leave.

Background: Antibiotic resistance is a global public health threat. Norway has managed to keep the incidence of resistant bacteria at a low level in both the healthcare system and the community. Reporting of both individual cases and meticillin-resistant Staphylococcus aureus (MRSA) outbreaks is mandatory. All isolates are genotyped., Aim: To describe the epidemiology of MRSA in Norway and to analyse how MRSA is spreading in a low-incidence country., Methods: All cases of laboratory-confirmed MRSA colonisation and infection reported in Norway from 2006 to 2010 were subject to epidemiological analysis., Findings: A total of 3620 cases of MRSA were found. Around one-third of the cases were imported, one-third acquired in the Norwegian healthcare system and one-third acquired in the community. Twelve percent of the cases were linked to known outbreaks. The total incidence of infected and colonized patients is slowly increasing. The numbers of severe infections remain stable at around 20 cases annually and the proportion of MRSA cases associated with healthcare has decreased., Conclusion: MRSA is still rare in the Norwegian population and the strategic objective of preventing MRSA from becoming a permanent part of the bacterial flora in hospitals and nursing homes has so far been met., (Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Influenza can be a serious, sometimes deadly, disease, especially for people in high-risk groups such as the elderly and patients with underlying, severe disease. In this paper we estimated the influenza-related excess mortality in Norway for 1975-2004, comparing it with dominant virus types and estimates of the reproduction number. Analysis was done using Poisson regression, explaining the weekly all-cause mortality by rates of reported influenza-like illness, together with markers for seasonal and year-to-year variation. The estimated excess mortality was the difference between the observed and predicted mortality, removing the influenza contribution from the prediction. We estimated the overall influenza-related excess mortality as 910 deaths per season, or 2.08% of the overall deaths. Age-grouped analyses indicated that the major part of the excess mortality occurred in the > or =65 years age group, but that there was also a significant contribution to mortality in the 0-4 years age group. Estimates of the reproduction number R, ranged from about 1 to 1.69.

In Norway there is an ongoing outbreak in pigs of infections with pandemic influenza A(H1N1)v virus. The first herd was confirmed positive on 10 October 2009. As of 26 October, a total of 23 herds have been diagnosed as positive. The majority of the herds seem to have been infected by humans. Sequence analysis of pig viruses from the index farm shows that they are identical or virtually identical to human viruses from the same geographical region.

A guidance document entitled "Recommended method for the establishment of Acceptable Operator Exposure Levels" has been prepared within the EU 5th Framework program. The paper describes the main outcomes of the project and the issues that apply particularly to agricultural workers and bystanders and the difficulties in developing an agreed uniform approach. The scientific basis of the process is discussed, to be used by the European Commission and Member States when making decision about the inclusion of an active substance in Annex 1 of Directive 91/414/EEC.

Effects of losartan and amlodipine on blood pressure and albuminuria were compared in a randomized, double-blind, parallel trial involving 48 patients with essential hypertension (sitting diastolic blood pressure between 95 to 115 mm Hg) and impaired renal function (creatinine clearance of 30 to 60 ml/min/1.73 m2). After four weeks of placebo administration, patients were stratified according to baseline albuminuria (< or > or = 300 micrograms/min) and randomized to once-daily treatment with losartan 50 mg (N = 24) or amlodipine 5 mg (N = 24) for 12 weeks. Titration to losartan 50 mg/hydrochlorothiazide (HCTZ) 12.5 mg or amlodipine 10 mg was possible at weeks 3 or 6 for patients having an inadequate blood pressure response. After 12 weeks of treatment, the mean decreases in sitting diastolic and systolic blood pressures were significantly larger in the losartan group (-18.1 +/- 7.2 and -27.7 +/- 15.2 mm Hg) than in the amlodipine group (-12.4 +/- 7.5 and -16.3 +/- 12.1 mm Hg; P = 0.009 and P = 0.008, respectively). The greater antihypertensive response to losartan was not influenced by the initial degree of albuminuria. The losartan and amlodipine regimens were well-tolerated. Baseline levels of albuminuria were reduced after 12 weeks of losartan treatment (median change of -29.5 micrograms/min), while amlodipine therapy was associated with a median increase (48.4 micrograms/min) in this renal marker at week 12. The treatment difference was statistically significant (P = 0.021). These results indicate that losartan 50 mg, administered alone or in combination with HCTZ 12.5 mg, is more effective than amlodipine 5/10 mg in lowering blood pressure and albuminuria in patients with essential hypertension complicated by impaired renal function.

The present study was designed to quantitatively assess radiographic changes in alveolar bone density in intrabony defects treated with expanded polytetrafluorethylene membranes (ePTFE) or by conventional flap surgery alone. 15 patients with 2 periodontal defects of comparable morphology which could be depicted on a single radiograph made up the test panel. Standardized radiographs of the periodontal defects were taken immediately prior to surgery and 12 months later. The 2 defects were treated simultaneously using the modified Widman flap procedure and prepared for membrane placement. Then one of the lesions was randomly assigned for treatment with the membrane. All radiographs and surgical procedures were managed by one person. The radiographs were assessed by another person according to a blind design. Periodontal defects treated with ePTFE membranes (test), and sites treated by conventional flap procedures (control) were then analyzed using a computerized image analysis program. In 8 patients, the test site outcome was better than the outcome in the control site. 6 of the control sites indicated increased bone density, while 7 sites showed decreased values, and 2 sites were unchanged. The corresponding values from the test sites were 5, 6 and 4, respectively. In the present controlled clinical study, the use of an ePTFE membrane to cover the opening of a vertical bone defects during periodontal surgery did not predictably increase the bone density of the defects.

In order to study differences in risk of the development of AIDS in different groups of HIV infected subjects, 151 homosexual men, 110 intravenous drug users (IVDUs) and 36 heterosexually infected persons without major signs of HIV infection at entry to the study were enrolled in a cohort study. The mean follow-up time was 35 months. At the end of follow-up 40 subjects (13%) were diagnosed as having AIDS. This represented 20% (31/151) of the homosexual men, 7% (8/110) of the IVDUs and 3% (1/36) of the heterosexual subjects. The probability of being AIDS-free 36 months after entering the study was 0.88 (0.84-0.92, 95% CI) for the total study population, 0.83 (0.77-0.90) for the homosexual men, 0.92 (0.86-0.99) for IVDUs and 0.93 (0.91-1.0) for heterosexual subjects (p < 0.05, log rank test). In a Cox regression analysis, adjusting for CD4+ cell count at study entry, the relative risk of AIDS progression was 2.4 (1.1-5.2) for homosexual men and 0.3 (0.04-2.4) for heterosexual subjects, compared with IVDUs. The results demonstrate a higher risk of AIDS for homosexual men during the follow-up period.

We use the unexpected results of five kidney biopsies to discuss how early biopsy in renal disease can change the therapy and correct the diagnosis of the disease. The first patient was a 73 year-old male diabetic who had osteomyelitis and developed rapidly progressive glomerulonephritis. The next patient was a 72 year-old man who was treated for cardiac failure and increasing serum creatinine. The kidney biopsy revealed rapidly progressive glomerulonephritis. The third patient developed acute renal failure after an episode with vomiting. Here the histological diagnosis was acute renal failure and parenchymatous renal disease could be ruled out. The next patient was a 13 year-old girl. She had proteinuria (5-6 g/d) and hypertension (200/140 mm Hg). After four months, serum creatinine was 200 mumol/l. She was then biopsied, and we found membranoproliferative glomerulonephritis type 1. After the diagnosis was established she was treated with immunosuppression and her condition improved. The last patient was a 55 year-old male diabetic. He developed nephrotic syndrome and the histological diagnosis of the kidney biopsy was membranous glomerulonephritis stage 1. Six months after the kidney biopsy we found carcinoma of the lung. This underlines the importance of the fact that 10% of membranous glomerulonephritides are tumour associated.