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The production of negative ions in cesium sputter ion sources is generally considered to be a pure surface process. It has been recently proposed that ion pair production could explain the higher-than-expected beam currents extracted from these ion sources, therefore opening the door for laser-assisted enhancement of the negative ion yield. We have tested this hypothesis by measuring the effect of various pulsed diode lasers on the O − beam current produced from Al 2 O 3 cathode of a cesium sputter ion source. It is expected that the ion pair production of O − requires populating the 5d electronic states of neutral cesium, thus implying that the process should be provoked only with specific wavelengths. Our experimental results provide evidence for the existence of a wavelength-dependent photo-assisted effect but cast doubt on its alleged resonant nature as the prompt enhancement of beam current can be observed with laser wavelengths exceeding a threshold photon energy. The beam current transients observed during the laser pulses suggest that the magnitude and longevity of the beam current enhancement depends on the cesium balance on the cathode surface. We conclude that the photo-assisted negative ion production could be of practical importance as it can more than double the extracted beam current under certain operational settings of the ion source. [ABSTRACT FROM AUTHOR]

It has been proposed that the negative ion yield of a caesium sputter ion source could be enhanced by promoting neutral caesium atoms to electronically excited 7p states supporting resonant ion pair production. We have tested this hypothesis by illuminating the cathode of a caesium sputter ion source with an adjustable wavelength laser and measuring its effect on the extracted beam currents of Oâˆ', Hâˆ' and Brâˆ' anions. The laser exposure causes the beam currents to increase but the effect is independent of the wavelength in the range of 440â€"460 nm, which leads us to conclude that there is no evidence for resonant ion pair production. The photon-induced beam current enhancement scales with the applied laser power and, depending on the ion source conditions, can more than double the extracted beam current. We present a qualitative explanation for the observed effect. The model, based on photoelectron emission and subsequent increase of the caesium sputtering rate, thus liberating negative ions from the cathode, is supported by the data demonstrating that the caesium sputter ion source can produce Brâˆ' beams without thermal surface ionization as a source of Cs+ ions, i.e. in external laser-driven mode without heating the surface ionizer. [ABSTRACT FROM AUTHOR]

We investigate the structural properties of GaAsBi layers grown by molecular beam epitaxy on GaAs at substrate temperatures between 220-315 °C. Irrespective of the growth temperature, the structures exhibited similar Bi compositions, and good overall crystal quality as deduced from X-Ray diffraction measurements. After thermal annealing at temperatures as low as 500 °C, the GaAsBi layers grown at the lowest temperatures exhibited a significant reduction of the lattice constant. The lattice variation was significantly larger for Bi-containing samples than for Bi-free low-temperature GaAs samples grown as a reference. Rutherford backscattering spectrometry gave no evidence of Bi diffusing out of the layer during annealing. However, dark-field and Z-contrast transmission electron microscopy analyses revealed the formation of GaAsBi clusters with a Bi content higher than in the surrounding matrix, as well as the presence of metallic As clusters. The apparent reduction of the lattice constant can be explained by a two-fold process: the diffusion of the excess As incorporated within AsGa antisites to As clusters, and the reduction of the Bi content in the GaAs matrix due to diffusion of Bi to GaAsBi clusters. Diffusion of both As and Bi are believed to be assisted by the native point defects, which are present in the low-temperature as-grown material. [ABSTRACT FROM AUTHOR]

In this paper we report a study of the effect of vacuum annealing at 400°C on the properties of normal metal-insulator-superconductor (NIS) tunnel junctions, with manganese doped aluminium (Al:Mn) as the normal metal, aluminum as the superconductor and amorphous aluminum oxide as the tunneling barrier (Al:Mn-AlOx-Al). The annealing treatment improves the stability of the junctions, increases their tunneling resistance and does not have a negative impact on the low-temperature current-voltage characteristics. The measured 1 / f resistance noise of the junctions also changes after annealing, in the best case decreasing by over an order of magnitude. All these observations show that annealing is a viable route to improve NIS junction devices after the sample has been fabricated. [ABSTRACT FROM AUTHOR]

Correction for 'Effect of the orientation and fluid flow on the accumulation of organotin compounds to Chemcatcher passive samplers' by H. Ahkola et al., Environ. Sci.: Processes Impacts, 2015, 17, 813–824, https://doi.org/10.1039/C4EM00585F. [ABSTRACT FROM AUTHOR]

Improvements in survival for patients with renal cell carcinoma have resulted in an increase in the burden of disease due to skeletal metastases, which are often solitary and resistant to radiotherapy. Surgical intervention remains a valid treatment to improve function and relieve pain, and replacement is able to achieve this and improve disease free implant survival. The aim of this study was identify prognostic factors for reconstruction survival of skeletal metastases in renal cell carcinoma and to characterise the nature of the reconstruction related complications. A retrospective analysis of all patients treated for metastatic renal cell carcinoma in three international bone tumour units between 2000 and 2014 identified 268 surgical interventions suitable for inclusion. Reconstruction survivorship was calculated using the Kaplan–Meier method whilst factors affecting reconstruction survival were assessed using Cox-regression multivariate analysis. Differences in proportions were assessed using Fisher's exact test. The overall rate of complications was 17%, which were classified as structural failure (7.1%), infection (4.9%) and tumour progression (3.7%). Endoprosthetic replacement when performed as the primary procedure demonstrate the best survivorship whilst factors associated with compromised reconstruction survival included previous surgical intervention and pre operative radiotherapy, and intralesional resection margins. We conclude that endoprosthetic replacement be considered as the index surgical intervention for skeletal metastases from renal cell carcinoma in certain locations as this carries the lowest incidence of complications. Revision of previous skeletal stabilisation, especially when combined with radiotherapy carries a high risk of complication, including infection, which often necessitates amputation. [ABSTRACT FROM AUTHOR]

Monitoring of harmful substances in an aquatic environment is based on spot sampling which is the only sampling technique accepted by environmental authorities in the European Union. Still the implementation of the European Union Water Framework Directive (WFD) requires novel sampling tools for monitoring priority pollutants since their concentrations in natural waters can often remain below the limit of detection when using the conventional spot sampling method. However, this does not necessarily mean that the pollutant is not present in the aquatic environment. Many chemicals that are considered to be harmful are bioaccumulative and can affect, e.g., reproduction of aquatic organisms even at very low concentration levels. Also the timing is crucial since with spot sampling the pulse of harmful substances can easily be missed. Passive samplers collect the compounds for a certain amount of time which allows the concentrations in the sampler to rise to the measurable level where they are easy to detect. Organotin compounds (OTCs) have been widely used as plastic stabilizers and antifouling agents in ship paints and in many industrial processes. Among the OTCs, tributyltin is listed as a WFD priority substance. In this study a small-scale flow simulation around the Chemcatcher passive sampler was performed to visualize the flow streamlines in the vicinity of the sampler and to study the pressure experienced by the receiving phase in different sampler positions. With laboratory experiments the sampling rates for each OTC were determined and the effect of the flow velocity and sampler orientation on the accumulation of OTCs is discussed. The pressure changes were observed on the surface of the receiving phase in simulations with varying sampler orientations. Despite that, the laboratory experiments discovered no difference in the accumulation of compounds when varying the sampler orientation. The concentrations of OTCs in the surrounding water calculated from the passive sampling results were equivalent to the spot sampling ones. Hence, the Chemcatcher passive sampler provides a practical tool for the implementation of WFD. [ABSTRACT FROM AUTHOR]

Underground nuclear weapon detonations release gaseous species into the atmosphere. The most interesting isotopes/isomers from the detection point of view are 131mXe, 133mXe, 133Xe and 135Xe. We have developed a method that employs high-precision Penning trap mass spectrometry at the JYFLTRAP facility, the University of Jyväskylä, to produce pure calibration samples of these isotopes/isomers. Among developments this work required a new mass resolution record of a few parts-per-million. Here the status and future plans of the project are reviewed. [ABSTRACT FROM AUTHOR]

Abstract: Atomic layer deposition (ALD) is currently a widespread method to grow conformal thin films with a sub-nm thickness control. By using ALD for nanolaminate oxides, it is possible to fine tune the electrical, optical and mechanical properties of thin films. In this study the elemental depth profiles and surface roughnesses were determined for Al2O3 +TiO2 nanolaminates with nominal single-layer thicknesses of 1, 2, 5, 10 and 20nm and total thickness between 40nm and 60nm. The depth profiles were measured by means of a time-of-flight elastic recoil detection analysis (ToF-ERDA) spectrometer recently installed at the University of Jyväskylä. In TOF-E measurements 63Cu, 35Cl, 12C and 4He ions with energies ranging from 0.5 to 10MeV, were used and depth profiles of the whole nanolaminate film could be analyzed down to 5nm individual layer thickness. [Copyright &y& Elsevier]

Background Few authors have investigated function and pain after surgical treatment of patients with bone metastases. In 1999 the Scandinavian Sarcoma Group (SSG) initiated the Skeletal Metastasis Registry as a multi-centric, prospective study to provide a scientific basis for recommendations of treatment. Patients and methods We have analyzed function and pain in 530 patients ( mean age 65 yr) operated on ( 599 operations) for non-spinal skeletal metastases at 9 SSG centres. 7% were operated for more than 1 metastasis. Carcinoma of the breast, prostate, kidney, and lung were the dominating sites for primary tumors. Results 25% of the patients died within 6 weeks after operation. 11% of the patients had complications. 6% had reoperation. In patients surviving more than 1 year the reoperation rate was 12%. 92% of the patients had no, light or moderate pain from metastasis at 6 weeks ( first control) and 6 months follow-up. Patients using opioids were reduced from 40% preoperative to 30% at 6 months after surgery. In patients with metastases in pelvis or lower extremity 79% were walking with or without crutches, 6 weeks and 88%, 6 months after surgery. More patients with metastases in proximal femur were mobile at 6 weeks and 6 months when treated with prosthetic replacement compared to internal fixation. Interpretation Palliative surgery for bone metastases improves function and reduce pain. Mobility is improved by surgery in patients with metastases in the pelvis or lower extremity. Prosthetic replacement seems to do better than internal fixation for metastases in the proximal femur. We need to analyze function and pain earlier than 6 weeks postoperative to investigate the benefit of surgery in patients with short time survival. [ABSTRACT FROM AUTHOR]

Background: Lifestyle and vascular factors have been linked to dementia and Alzheimer’s disease (AD), but the role of dietary fats in the development of dementia is less clear. Methods: Participants were derived from random, population-based samples initially studied in midlife (1972, 1977, 1982, or 1987). Fat intake from spreads and milk products was assessed using a structured questionnaire and an interview. After an average follow-up of 21 years, a total of 1,449 (73%) individuals aged 65–80 years participated in the re-examination in 1998. Altogether 117 persons had dementia. Results: Moderate intake of polyunsaturated fats at midlife decreased the risk of dementia even after adjustment for demographic variables, other subtypes of fats, vascular risk factors and disorders, and apolipoprotein E (ApoE) genotype (OR 0.40, CI 0.17–0.94 for the 2nd quartile vs. 1st quartile), whereas saturated fat intake was associated with an increased risk (OR 2.45, CI 1.10–5.47 for the 2nd quartile). The associations were seen only among the ApoE ε4 carriers. Conclusions: Moderate intake of unsaturated fats at midlife is protective, whereas a moderate intake of saturated fats may increase the risk of dementia and AD, especially among ApoE ε4 carriers. Thus, dietary interventions may potentially modify the risk of dementia, particularly among genetically susceptible individuals. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Highlights the Skeletal Metastasis Register of the Scandinavian Sarcoma Group (SSG) that provides a scientific basis for treatment recommendations of the disease. Analysis of the survival of patients with skeletal metastases surgically treated at nine SSG centers; Relation of the survival to bone localization, skeletal metastatic load and presence of visceral metastases; Application of multivariate regression analysis.

BACKGROUND: Evidence suggests that dietary supplementation of L-arginine, the precursor of nitric oxide, may protect arteries against atherosclerosis. OBJECTIVE: We tested the hypothesis that dietary arginine intake is associated with a decreased risk of acute coronary events in Finnish men aged 42-60 y. DESIGN: We investigated this association in a prospective cohort study of men who were free of prior coronary artery disease and who were examined in 1984-1989 in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD). The dietary arginine intake of 1981 men was assessed by a 4-d food intake record during the baseline phase of the KIHD. RESULTS: Men in the highest quintile of dietary arginine intake (>or= 5691 mg/d) did not have a significantly lower risk of acute coronary events than did men in the 4 lower quintiles (relative risk after adjustment for potential coronary risk factors: 1.28; 95% CI: 0.85, 1.94). The covariates were age; examination years; body mass index; systolic blood pressure; serum total, HDL, and LDL cholesterol; serum triacylglycerols; urinary excretion of nicotine metabolites; maximal oxygen uptake in an exercise test; and alcohol intake. Splitting arginine intake into deciles or analyzing plant- and animal-derived arginine separately did not show any association between dietary arginine intake and the risk of acute coronary events. Arginine intake was also not consistently associated with blood pressure. CONCLUSION: Dietary arginine intake is not associated with the risk of acute coronary events in middle-aged men in eastern Finland. Copyright © 2002 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Gene therapy for the treatment of atherosclerosis and related diseases has shown its potential in animal models and in the first human trials. Gene transfer to the vascular system can be performed both via intravascular and extravascular periadventitial routes. Intravascular gene transfer can be done with several types of catheters under fluoroscopic control. Extra-vascular gene transfer, on the other hand, provides a well-targeted gene delivery route available during vascular surgery. It can be done with direct injection or by using perivascular cuffs or surgical collagen sheets. Ex vivo gene delivery via transfected smooth muscle cells or endothelial cells might be useful for the production of secreted therapeutic compounds. Gene transfer to the liver has been used for the treatment of hyperlipidemia. The first clinical trials for the induction of therapeutic angiogenesis in ischemic myocardium or peripheral muscles with VEGF or FGF gene transfer are under way and preliminary results are promising. VEGF has also been used for the prevention of postangioplasty restenosis because of its capability to induce endothelial repair and production of NO and prostacyclin. However, further basic research is needed to fully understand the pathophysiological mechanisms involved in conditions related to atherosclerosis. Also, further development of gene transfer vectors and gene delivery techniques will improve the efficacy and safety of human gene therapy. [ABSTRACT FROM AUTHOR]

Mindlin-type plate and shell finite elements are the most widely used ones in the analysis of laminated composite structures. In the commercially available finite element programs, the transverse shear correction factors for these elements are usually the same as for structures made of isotropic materials. In the paper the shear correction factors are determined using energy principles for general laminates in cylindrical bending. Results for various materials and laminates are presented. [ABSTRACT FROM AUTHOR]