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To build and validate a prognostic model that predicts long-term overall survival (OS) in metastatic choroidal and ciliary body melanoma (CCBM) to facilitate patient counseling and planning, reporting, and interpreting clinical trials.Retrospective cohort study with validation.We analyzed predictors of intermediate (IMT; 25-42 months) and long-term (LT; ≥42 months) OS in a Finnish nationwide cohort of 330 patients with metastatic CCBM. Short-term (25 months), IMT and LT survival were compared with pairwise and ordinal logistic regression. A single-center cohort of 259 patients from Italy was used for validation. Models were compared with deviance test.Median OS was 12 and 17 months in the building and validation dataset, respectively; 40 (12%) and 31 (9%) as compared to 44 (17%) and 32 (12%) patients were IMT and LT survivors, respectively. Alkaline phosphatase (AP) or lactate dehydrogenase (LD) level never exceeded 2 x upper normal limit (UNL) in either LT cohort. Conditional to both being ≤2 x UNL, distant metastasis-free interval (DMFI)42 months (OR 4.09-4.64; p.001) paired with age60 years (OR 3.23, p=.002), having no symptoms (OR 4.19, p=.005), and the largest diameter of the largest metastasis30 mm (TNM M1a; OR 3.05, p=.001) independently predicted higher odds of surviving longer (IMT or LT) without model preference. These results were confirmed in the validation dataset.AP or LD2 x UNL essentially precluded LT survival. The most robust predictor otherwise was DMFI42 months, followed by age60 years, absence of symptoms, and TNM M1a.

Uveal melanoma (UM) is a rare intraocular cancer with the highest incidence in northern latitudes. Metastases develop in approximately 50% of patients, whereafter the median survival is 13 months. Generally, the mutation burden of these tumors is low. Germline variants predisposing to UM have been previously described in BRCA1-associated protein 1 (BAP1). Recently, germline and somatic loss-of-function (LOF) variants in the methyl-CpG-binding domain 4 (MBD4) gene have been found to cause a hypermutated UM, and MBD4 also has been put forward as a gene predisposing to UM. We sequenced for MBD4 germline variants in 440 Finnish patients with UM and identified seven rare exonic missense variants in 16 (3.6%) patients, of which one likely alters MBD4 function. The frequency of likely pathogenic variants in our cohort is 0.23% (1/432; 95% CI, 0.01-1.28). We identified no LOF variants though their frequency in the Finnish population is 0.052%. Thus, our data do not support the suggestion that MBD4 germline variants predispose to UM. Somatic loss of MBD4 might modify the mutational burden in UM and change its response to immune checkpoint inhibitors.

Uveal Melanoma (UM) is the most common primary intra-ocular tumor in adults. New diagnostic procedures and basic science discoveries continue to change our patient management paradigms. A recent meeting of the European Vision Institute (EVI) special interest focus group was held on “Outcome Measures of New Technologies in Uveal Melanoma”, addressing the latest advances in UM, starting with genetic developments, then moving on to imaging and treatment of the primary tumor, as well as to investigating the most recent developments in treating metastases, and eventually taking care of the patient’s wellbeing. This review highlights the meeting’s presentations in the context of the published literature.

Treatment of primary intraocular uveal melanoma has developed considerably, its driver genes are largely unraveled, and the ways to assess its risk for metastases are very precise, being based on an international staging system and genetic data. Unfortunately, the risk of distant metastases, which emerge in approximately one half of all patients, is unaltered. Metastases are the leading single cause of death after uveal melanoma is diagnosed, yet no consensus exists regarding surveillance, staging, and treatment of disseminated disease, and survival has not improved until recently. The final frontier in conquering uveal melanoma lies in solving these issues to cure metastatic disease. Most studies on metastatic uveal melanoma are small, uncontrolled, retrospective, and do not report staging. Meta-analyses confirm a median overall survival of 10-13 months, and a cure rate that approaches nil, although survival exceeding 5 years is possible, estimated 2% either with first-line treatment or with best supportive care. Hepatic ultrasonography and magnetic resonance imaging as surveillance methods have a sensitivity of 95-100% and 83-100%, respectively, to detect metastases without radiation hazard according to prevailing evidence, but computed tomography is necessary for staging. No blood-based tests additional to liver function tests are generally accepted. Three validated staging systems predict, each in defined situations, overall survival after metastasis. Their essential components include measures of tumor burden, liver function, and performance status or metastasis free interval. Age and gender may additionally influence survival. Exceptional mutational events in metastases may make them susceptible to checkpoint inhibitors. In a large meta-analysis, surgical treatment was associated with 6 months longer median overall survival as compared to conventional chemotherapy and, recently, tebentafusp as first-line treatment at the first interim analysis of a randomized phase III trial likewise provided a 6 months longer median overall survival compared to investigator's choice, mostly pembrolizumab; these treatments currently apply to selected patients. Promoting dormancy of micrometastases, harmonizing surveillance protocols, promoting staging, identifying predictive factors, initiating controlled clinical trials, and standardizing reporting will be critical steppingstones in reaching the final frontier of curing metastatic uveal melanoma.

As long as 25 years after treatment of primary uveal melanoma (UM), metastases are the leading cause of death and, eventually, over 50% of patients die of metastatic disease [1,2]. The liver is the...

Purpose To evaluate the consistency of hepatic ultrasonography (US) with staging computed tomography (CT) and magnetic resonance imaging (MRI), to analyze why US was inconsistent with CT/MRI, and to compare CT/MRI. Design Reliability analysis. Methods Two hundred fifteen patients whose primary uveal melanoma was managed in the Helsinki University Hospital and who were diagnosed with hepatic metastases by US within 60 days of staging CT/MRI from January 1999 to December 2016 were included. Patients attended a real-life follow-up schedule including hepatic US, liver function tests (LFT), and a confirmatory CT/MRI. We evaluated the consistency of US with staging CT/MRI regarding the presence and number of metastases. Results The enrolled patients underwent 215 US, 167 CT, and 69 MRI examinations, and 67% of them had biopsy-confirmed metastases. Screening was regular for 98% of the patients, and 66% were asymptomatic. US was fully consistent with CT/MRI in detecting metastases in 113 (53%) patients, in 63 (29%) CT/MRI showed more metastases, and in 16 (7%) CT/MRI showed fewer metastases than US. CT/MRI was inconsistent with US in 23 (11%) patients. The sensitivity of US in detecting metastases was 96% (95% confidence interval, 92-98). US failed to suggest metastases in 10 patients. LFT were abnormal in 6 of them, and a newly detected hepatic lesion was present by US in 4. Conclusions Hepatic US is a sensitive screening modality in detecting metastases in patients with primary uveal melanoma, if combined with LFT and, in case of any newly detected lesion, a confirmatory MRI.

We conducted a retrospective population-based study of 140 episodes of Streptococcus dysgalactiae subsp. equisimilis bacteremia occurring in Finland during 1995–2004. Rare emm types were associated with more severe disease and increased mortality rates. Skin and soft tissue infections were more frequent clinical signs among cases caused by common emm types.

The present work develops a methodology for the analysis of transient signals for fault detection and diagnosis in electrical motors. The objective of this work is the initial development of a Prognostic and Health Monitoring System (PHMS) for the demagnetization of the magnetic field source of a Permanent Magnet Synchronous Motor (PMSM) used in electrical vehicles. The developed methodology is based on the Hilbert-Huang Transform (HHT), a technique which is particularly suitable for processing oscillating transient signals, such as the stator currents typical of automotive electric traction machines. The HHT represents a time-dependent series in a two-dimensional time-frequency domain by extracting instantaneous frequency components within the signal through an Empirical Mode Decomposition (EMD) process. The developed framework has been applied to four transients simulating different levels of demagnetization of the permanent magnet of the PMSM; the obtained results show that HHT enables us to detect and assess the degradation level for a demagnetized core of a PMSM.

Oxygen adsorption, dissociation and desorption kinetics at the SnO2 surface is simulated. Both the temperature dependence of equilibrium coverages of various forms of oxygen and their transient behavior in varying temperature are considered. The model is based on our earlier work on rate equation simulations of ionosorbed oxygen, but now refined to include the “bridging” lattice oxygen atoms on the surface. Model for the electrical conductance of porous SnO2 material as a function of temperature and in terms of the effects from surface coverages of different oxygen components is presented. With the present model, we are able to simulate the essential features in the experimental conductance dependence.

Tin dioxide is a widely used material in gas sensing applications. This is partly due to its stable surface structure and high sensitivity to many gases. The interaction of different gas components with an oxide surface may lead to changes in the lattice oxygen content at the surface in addition to changes in the amount of adsorbed species. The electronic and atomic structures of the surface change with the changes in the lattice oxygen content. This leads to surface relaxation and changes in the surface dipole layer of the ionic surface in addition to changes in the Schottky barrier which is a result of the charge accumulation onto the surface from the bulk of the semiconducting oxide. Changes in both the dipole layer and the Schottky barrier change the work function of the semiconductor and may reflect in its electrical conductivity. Here we have used first-principles calculations based on LDA-SCF to study changes in the electronic and atomic structures of the SnO 2 (110) surface as a result of oxygen exchange between the lattice and the ambient gas. The transducer function relating the changes at the surface to the changes in the conductivity of a ceramic microstructure is also described by an example.

Surface relaxation of the stoichiometric and reduced SnO2 (110) surfaces is studied with first-principles calculations. Calculations are carried out with two different self-consistent ab initio LDA methods, which lead to similar results. The most prominent feature in the relaxation is that the surface layer oxygens of the reduced surface move outwards about 0.4 A with respect to the surface tin atoms. The stoichiometric (oxidized) surface is stabilized by the “bridging” oxygen atoms, and therefore, relaxes less. The valence band density-of-states is similar at both surfaces, except that removing bridging oxygens leaves behind electrons that occupy gap states formed at the reduced tin atoms.

Some computational approaches to the chemical sensitivity of semiconducting tin dioxide are presented. Chemical sensitivity is often observed using conductance measurement. Therefore, the potential energy barriers in grain contacts between adjacent grains of a polycrystalline semiconductor are the key parameters for transducing the chemical surface sensitivity into the conductance response. The rate equation model describes the electronic exchange between the adsorbed oxygen species and the bulk conduction band of a semiconductor. It predicts the type of the major negative oxygen ion (O2− or O−) at the surface as a function of temperature in agreement with experimental findings. The grain geometry has only a small effect on the potential energy barrier at the surface of finite grains. Even a small neck contact between grains, in the case of mobile donors, decreases strongly the potential energy barrier between grains compared to that in the case of an open grain contact. Results from Monte Carlo simulations with random barrier networks reveal that the current–voltage characteristic of a polycrystalline semiconductor is non-linear at higher voltages and the non-linearity of the network increases with increasing width of the barrier distributions. Electronic-structure calculations with clusters give qualitative information on the role of oxygen vacancies in different atomic planes in SnO2 and its unrelaxed and unreconstructed (110) surface.

Fully Electric Vehicles (FEVs) for mass production present new challenges for automotive manufacturers. In particular, the relative immaturity of new building blocks such as motors and control components may have an impact on the safety and reliability of FEVs. In this context, one of the main objectives of the European FP7 Electrical Powertrain Health Monitoring for Increased Safety of FEVs (HEMIS) project is to design a Prognostic and Health Management System (PHMS), aiming to increasing the safety and availability of FEVs. This paper describes the practical procedures used to identify the most critical degradation mechanisms which can occur in FEV components, and for the development and verification of the PHMS algorithms. The analysis is focused on two of the most critical components: the Permanent Magnet Synchronous Machine (PMSM), and the FEV control capacitor.

A short survey is given of our computational approach for the study of the chemical surface sensitivity of some oxide and sulphide semiconductors. Many oxides and sulphides behave as n-type semiconductors with donors originating from nonstoichiometric defects. Therefore, n-type semiconductors with negligible hole concentrations are considered here. Chemical activity of n-type semiconductor surfaces is based on adsorbate interactions both with conduction-band bulk electrons and with localized electrons trapped at surface states. Some effects may also origin from a possible ionic response of the semiconductor to changing internal electric fields. A dynamical approach with expressions similar to those for the generation-recombination processes (Schockley-Hall-Read theory) is used to describe adsorbate interactions with conduction-band bulk electrons. As practical examples we consider SnO2(110) − 1 × 1 and wurtzite CdS(1010) − 1 × 1 surfaces, both being the most stable faces of their structures, respectively, and nonpolar in the bulk derived geometry. With the SnO2(110) surface we use clusters in calculations of localized electronic surface states originating from different defects, while a slab method is used to calculate the atomic relaxation at the CdS(1010) surface.

Sintered ceramic semiconductors can be used to monitor the surrounding gas atmosphere. It is based on the conductivity response of the semiconductor to the surface reactions on the grains of porous material. Some nonstoichiometry defect donors, like oxygen vacancies in n‐type semiconductors, may be mobile at relatively low temperatures, where semiconductor gas sensors operate. In such case, the donor concentration may considerably decrease in the space charge layer at the semiconductor surface, which may be reflected in the transport properties of electrons through the neck contacts between grains. We model here various neck contacts between spherical grains and compute the electrical potential at the conductive region from the Poisson–Boltzmann equation in cases of mobile single and double donors. The solutions are evaluated numerically with a finite difference method. According to the Schottky‐defect model for oxygen vacancies, the surface concentration of donors is kept a fixed parameter in the calcula...

A treatment of the surface energy barrier is given for n-type semiconductors in the case of mobile donors. We consider finite grains and solve the Poisson-Boltzmann equation, related to the problem, for one-dimensional (slab shape), two-dimensional (cylindrical-rod shape) and three-dimensional (spherical shape) grain geometries. Analytical solutions are given for the band bending and surface energy barrier in one- and two-dimensional grain geometries in the case of total grain depletion, and a numerical approach was used to calculate the results in spherical grains and also in partially depleted grains. Tin dioxide is used as an example to illustrate grain depletion in ambient oxygen atmosphere in the case of mobile oxygen-vacancy donors.

Atomic geometry and electronic density of states of the wurtzite CdS (10 1 0) cleavage surface have been calculated. Calculations were carried out with two different self-consistent ab initio LDA methods leading to similar results. Surface relaxation is found to be strong: cations relax towards bulk and anions outwards from the surface. This is in accordance with experimental observations and other published calculations.

A cluster approach has been used for the simulation of the adsorption of oxygen and carbon monoxide on SnO 2 and CdS surfaces. Computations are based on an ab initio method, the local-density approximation and atomic orbitals as a basis set. Solutions are calculated self consistently. The atomic orbital nature (origin) of the cluster levels is traced by the projection onto the atomic basis set. The results refer to clusters modelling SnO 2 (110) and CdS (101−0) faces without any surface reconstructions. Energy levels related to metallic surface species with different coordination are described for the basic SnO 2 and CdS clusters, together with levels originating from O 2 and CO adsorbates. The shifts of the levels formed by chemisorbed complexes are described in connection with the band scheme of the semiconductor.

The role of metformin in the treatment of infertility in women with polycystic ovary syndrome (PCOS) is still controversial. OBJECTIVE AND OUTCOMES: We investigated whether metformin decreases the early miscarriage rate and improves the pregnancy rates (PR) and live-birth rates (LBR) in PCOS.This was a multicenter, randomized (1:1), double-blind, placebo-controlled study. Three hundred twenty women with PCOS and anovulatory infertility were randomized to metformin (n = 160, Diformin; obese women, 1000 mg two times daily; nonobese subjects, 500 mg + 1000 mg daily) or identical doses of placebo (n = 160). After 3 months' treatment, another appropriate infertility treatment was combined if necessary. If pregnancy occurred, metformin/placebo was continued up to the 12th week.Miscarriage rates were low and similar in the two groups (metformin 15.2% vs. placebo 17.9%, P = 0.8). Intent-to-treat analysis showed that metformin significantly improved PR and LBR (vs. placebo) in the whole study population (PR: 53.6 vs. 40.4%, P = 0.006; LBR: 41.9 vs. 28.8%, P = 0.014) and PR in obese women (49.0 vs. 31.4%, P = 0.04), and there was a similar trend in nonobese (PR: 58.6 vs. 47.6%, P = 0.09; LBR: 46.7 vs. 34.5%, P = 0.09) and in obese women with regard to LBR (35.7 vs. 21.9%, P = 0.07). Cox regression analysis showed that metformin plus standard infertility treatment increased the chance of pregnancy 1.6 times (hazard rate 1.6, 95% confidence interval 1.13-2.27).Obese women especially seem to benefit from 3 months' pretreatment with metformin and its combination thereafter with routine ovulation induction in anovulatory infertility.

The present study starts with mobile oxygen-vacancy donors in an n-type oxidic semiconductor and considers the height of the energy barrier at the semiconductor surface at different temperatures in oxygen-containing atmosphere. Surface concentrations of the oxygen vacancies are used as input data for the computer simulation and both the diffusion and drift components of the current of these positive donors in the electric field of the space-charge layer are considered. Charge distributions of either single or double donors with the charge distribution of electrons have been the starting point for the solution of Poisson's equation for the electric surface potential. Some rate equations tested in an earlier study are used in the computations to describe the electron transfer between the conduction band of the semiconductor and the oxygen surface species (O2, O2- O-). The concept of mobile oxygen-vacancy donors seems to be a reality, at least in high-temperature applications like TiO2 lambda sensors. An aim of this work was to study the effect of freezing the oxygen-vacancy distribution at a specific temperature on the temperature dependence of the height of the surface energy barrier.

Some results are given from a cluster approach for the electronic structure of the SnO 2 (110) face together with some oxygen vacancies and ‘adsorbates’. Computations are based on ab initio methods, the local-density approximation and atomic orbitals as a basis set. Solutions were calculated self-consistently, but also using a composition of atomic potentials (for some smaller clusters). The atomic-orbital nature (origin) of the cluster levels was traced by projection onto the atomic bases set. The results here refer to a basic cluster [SnO 2 13 with 17 surface atoms moedelling the SnO 2 (110) face and the other 22 atoms in the next five suface layers. The effect of oxyggen ’adsrobates‘ and oxygen vacancies in the few uppermost subsurface layers on the electronic structure was considered. In particular, the focus was on the levels related to oxygen vacancies and originating from Sn 5s orbitals, which are well-known donor levels in the deep bulk, making SnO 2 an n-type semiconductor. The results support some other theoretical and experimental predictions that oxygen vacancies behave as neutral defects at or near SnO 2 surfaces.

An ab initio cluster approach (LDA-SCF) is used to study the electronic structure of the SnO2 (110)-1 × 1 surface without any relaxation and reconstruction. Modelling is made for the ideal nonpolar surface and also for surfaces containing different kinds of oxygen vacancies, foreign impurities and adsorbates. Computations are based on the linear combination of atomic orbitals (LCAO), which allows the population analysis through projection of the molecular orbitals onto the atomic basis set. This is used to trace the atomic character of the cluster levels. A cluster with 103 atoms Sn32O71 is used to model the ideal SnO2 (110) surface, the most stable and thus the dominant crystallite face of the polycrystalline SnO2, and the next few bulk layers. The results here refer to both the ideal nonpolar (110) surface and some oxygen-deficient polar (110) surfaces. Chromium and NO are taken as examples of impurity atoms and adsorbate molecules, respectively. Based on the results we are able to suggest an explanation for the observed strong decrease of conductivity of SnO2 polycrystalline films and the enhanced adsorption and dissociation of NO on the SnO2 surface due to adding of chromium impurities.

The aim of this study was to investigate the emm types and superantigen profiles of bacteraemic group A streptococcal (GAS; Streptococcus pyogenes) isolates and to detect possible associations between the molecular characteristics of isolates and the clinical presentations of disease. In this population-based study, 87 bacteraemic GAS isolates from adult patients in Pirkanmaa Health District (HD), Finland, during the period 1995-2004 were emm typed and genotyped for superantigen (SAg) profiles. The epidemiological and clinical data of the patients were analysed with the microbiological characterisation data. Among the 87 isolates, 18 different emm types were found. emm1, emm28 and emm81 were the three most common types, covering 52% of isolates. The prevalence of specific emm types showed high variability during the 10-year study period. We could not find any association between the emm type and clinical features of bacteraemic infection, such as underlying diseases, disease manifestations or case fatality. Of nine superantigen genes examined, speA and speC were identified in 20 and 30% of the strains, respectively. No association was found between disease manifestation and the presence of single superantigen genes. The 26-valent GAS vaccine would have covered only 62% of isolates causing invasive disease in Pirkanmaa HD during the study period.

The non-ohmic conductance behaviour of some SnO 2 -based thick-film sensors has been studied both by a computer simulation and by practical experiments. Current-voltage characteristics have been measured in the voltage range 0–20 V at different temperatures. In the computer simulation, a three-dimensional random barrier network is used to describe polycrystalline SnO 2 thick films. The basic unit in the network is a component describing the surface Schottky barrier at intergrain contacts and obeying non-ohmic behaviour. IU characteristics have been calculated at different temperatures for networks with different coordination and with different distributions of barrier heights. Results both of the simulation calculations and of experiments show a strong non-linearity at low temperatures, but this behaviour decrease with increasing temperature. Some comparisons between calculated results and those from analytical expressions are also given in the ohmic range at low voltages.

Rate equation simulatin is used in the present computational approach in order to study the role of different adsorbed oxygen ions (O 2 − and O − ) in controlling the height of the Schottky barrier at the surface of SnO 2 , a key material in the field of semiconductor gas sensors. Computations are based on the adsorption/desorption model and consider the electron transfer between different oxygen species on the surface and the bulk conduction band. Different values have been tested for both the frequency factors and the activation energies of the rate constants in order to consider the relative population between the O − and O 2 − ions on the surface at different temperatures, the dependence of the height of the surface Schottky barrier on temperature and oxygen partial pressure, and also the response and recovery times of the barrier heights as a consequence of rapid temperature changes. Comparisons of calculated barrier heights with some empirical values are also given at different temperatures and oxygen partial pressures.

Purpose: To evaluate the outcome of 180° micropulse diode laser trabeculoplasty (MDLT) in patients with open-angle glaucoma. Methods: A retrospective review of 40 eyes of 29 MDLT-treated patients with a minimum follow-up time of 6 months. Successful outcome was defined as follows: (i) a ≥20% or (ii) a ≥3-mmHg decrease of intraocular pressure (IOP), no further need for laser- or incisional surgery and the number of glaucoma medication was the same or less than preoperative. These definitions will from now on be referred to as definition one and definition two. Results: Life-table analysis showed an overall success rate of 2.5% (1/40) and 7.5% (3/40) (according to definitions one and two, respectively) after up to 19 months of follow-up. The average time for failure was by definition one 2.9 months (standard deviation, SD ± 3.5, range 1–12 months) and by definition two 3.3 months (SD ± 3.9, range 1–16 months). There were no intra- or postoperative complications caused by MDLT. Postoperative inflammatory reaction, cells and flare, was scanty. Conclusion: Our results suggest that 180° MDLT is a safe but ineffective treatment in patients with open-angle glaucoma.

The H2S response of some SnO2-based thick-film gas sensors containing Ag and Al2O3 has been studied in the concentration range 0 to 10 ppm. Several different operational parameters related to the response and recovery times, sensitivity and the interfering effects of NO, CO and H2O have been tested. The response measurements are carried out both in the constant-temperature and temperature-pulsed modes in order to find the advantages of each mode in relation to sensitivity, selectivity and response time. In the case of temperature pulsing, both the response and recovery times are very short compared to those in the constant-temperature mode. The constant-temperature mode, however, has to be used at concentrations below 0.5 ppm, which is about the observation limit in the case of temperature pulsing. The interfering effects of both CO and NO are small in the case of the constant-temperature mode, but very pronounced in the case of temperature pulsing. Some experiments concerning monitoring of H2S as a pollutant in city air have also been conducted with the present sensors.

In this population-based study, all 314 episodes of beta-haemolytic streptococcal bacteraemia in adult patients in the Pirkanmaa area, Finland, during the 10-year period 1995-2004 were retrospectively reviewed. Altogether, 92 cases of bacteraemia caused by Lancefield group A beta-haemolytic streptococci (GAS), 76 caused by group B beta-haemolytic streptococci (GBS), 18 caused by group C beta-haemolytic streptococci (GCS) and 128 caused by group G beta-haemolytic streptococci (GGS) were identified. The most important finding was that the incidence of GGS increased during the study period. Disruption of the cutaneous barrier was a very common predisposing factor in GAS and GGS bacteraemias. Skin infections were the presenting clinical manifestations in two-thirds of GAS and GGS bacteraemias.

Conductance responses of some sintered samples of SnO 2 prepared in the form of thick films have been studied in the CO concentration range from one ppm upwards in dry synthetic air and also in ambients containing different amounts of humidity. The experiments have been carried out both at equilibrium conditions, by allowing the samples to stabilize at different constant temperatures, and at non-equilibrium conditions, by continuously cycling the sensors between two temperatures. The effects of different electrode materials and of some additives like antimony in SnO 2 on the conductance response to CO under equilibrium and non-equilibrium conditions have been studied. In this paper the emphasis is to describe some measurements concerning a peculiar effect of electrode materials (between Au and Pt) and Sb doping on the conductance response to CO in the temperature-pulsed mode of sensor operation. A drastic difference in the non-equilibrium conductance response to CO in ambients containing humidity is found between Sb-doped SnO 2 sensors with Au and Pt as electrode materials.

It is well known that the selectivity of tin oxide gas sensors is not very good. In particular, if the sensors are submitted to real life conditions, their response becomes ambiguous because of ambient water vapour. There are several techniques to cope with this problem. A first method to decrease the influence of the relative humidity is to incorporate additives into the tin oxide. However, with this method it is impossible to eliminate the influence of water to an acceptable level. Another method is to use an array of sensors and to convert the response of this array by means of mathematical algorithms, in order to obtain a response that is insensitive to water vapour. The method presented in this paper consists of switching a single tin oxide gas sensor between two well-defined temperatures. With this method, it is possible to decrease the sensitivity to water vapour to an acceptable level, while the high sensitivity to CO is unaffected.

Summary Objectives Several factors associated with mortality in Lancefield group A beta-hemolytic streptococcal bacteremia have been described in population-based surveillance studies, whereas such reports on group B, C, and G streptococcal are scant. Methods In this population-based study all 314 episodes of beta-hemolytic streptococcal bacteremia in adult patients in the Pirkanmaa area, Finland, during the 10-year period 1995–2004 were retrospectively reviewed. Results The 30-day case-fatality rate was 13%, being highest in group C (22%); in group A it was 15%, in group B 7%, and in group G 15%. Confusion, unconsciousness and dyspnea as the first sign or symptom were associated with increased case-fatality, while fever seemed to be a protecting factor for death. Alcoholism and ultimately or rapidly fatal underlying disease were significantly associated with increased case-fatality. Among infections of the skin and soft-tissues, necrotizing fasciitis had the highest risk of death (38%), while patients with cellulitis had a case-fatality of 8%. A history of previous cellulitis seemed to protect against death (case-fatality of 3% as compared to 16% among those without such a history ( p =0.014)). Conclusion A history of previous cellulitis seemed to be a protecting factor against death. Fever was also associated with a good prognosis.

This paper presents measurement-based calculations for actual aggregate and link throughputs of Bluetooth system. The co-interference between fully loaded piconets formed in a 10*10 sq. meter room is inspected. The results show that the maximum aggregate throughput is gained with 45 active piconets. When comparing the ideal performance with the one based on measured results best overall performance over a distance of 10 meters can be achieved using DM5, DM3 and DH1 packets for data transfer. When the distance is less than 3 meters the use of only DH packets gives the best results.

Tin dioxide (SnO2) is a wide-gap semiconductor with applications as gas sensor material and catalyst. The structure and electronic properties of its surface have been experimentally studied in detail [1, 2]. Also theoretical investigations of oxide surfaces based on an accurate first-principles calculations have been carried out [3, 4, 5, 6]. Such approaches allow one to create an atomistic picture of sensing mechanisms and methods for prognosis of gas response properties of the semiconducting materials.

Introduces a new probability density function (pdf) estimation method based on the concept of order statistic filter banks. The proposed method offers a new kind of possibility for statistical analysis of signals with real time processing capabilities. Besides the new real time processing method offers a procedure to control such properties of the pdf estimate as the variance and the resolution. >

An important positive regulator of the cell cycle, cyclin D1, is often amplified and overexpressed in malignancies. Cyclin D1 aberrations were analysed in grade II-IV astrocytomas by fluorescence in situ hybridization (FISH), mRNA in situ hybridization and immunohistochemistry. Proliferation activity was determined by Ki-67(MIB-1) immunolabelling and mitotic counting. High cyclin D1 expression was observed in grade IV astrocytomas (grades II-III versus grade IV; mRNA expression: p0.001; immunoexpression: p=0.013), and correlated with poor patient survival (p0.001, n=46). Upregulated cyclin D1 expression was also closely associated with poor patient prognosis in grade II-III astrocytomas (p0.001, n=30). Cyclin D1 gene was not found to be amplified (n=7). Cell proliferation activity was significantly increased in tumours exhibiting high cyclin D1 mRNA levels (Ki-67(MIB-1): p0.001; mitotic count: p0.001) and high cyclin D1 protein expression (Ki-67(MIB-1): p=0.002; mitotic count: p=0.012). These results indicate that increased production of cyclin D1 is closely associated with high cell proliferation activity and aggressive behaviour in diffusely infiltrating astrocytomas.

There is evidence that tumor angiogenesis, as detected by immunohistochemical staining of endothelium, is of prognostic significance in breast cancer. However, little attention has been paid to possible differences between antibodies or to quantitation of the stained microvessels. We compared three endothelial cell antibodies [anti-human von Willebrand factor (anti-VWF, also termed factor VIII), anti-CD31, and anti-CD34] in archival paraffin-embedded specimens. Anti-CD34 and anti-VWF showed better staining performances than anti-CD31, although the staining results with different antibodies were comparable. Two different methods of microvessel quantitation (the highest microvessel count and percentage microvessel area) were evaluated and also showed significant correlation. From a retrospective database (n = 1000), 77 axillary node-negative invasive ductal breast carcinomas were selected on the basis of clinical outcome to maximize the prognostic power of the sample set (37 died due to a metastatic breast carcinoma, 40 showed no recurrence during 8-yr follow-up). Microvessel quantitations were related to flow cytometric DNA ploidy, c-erb-B-2 overexpression, and estrogen receptor status of the tumor. Surprisingly, neither highest microvessel counts nor microvessel area measurements quantitated with anti-CD34 or anti-VWF immunohistochemistry were able to discriminate between favorable and unfavorable outcome patients. Thus, our results suggest that further evidence is still needed on tumor angiogenesis immunohistochemistry before it can be adopted as a prognostic marker in routine, clinical practice.

Oxide semiconductors form a group of compounds whose specific properties of surfaces and interfaces are used for gas sensing. Our fundamental understanding of the operation principles of these devices is still insufficient. The abundance of phenomena on open oxide–semiconductor surfaces at elevated operation temperatures of the sensors is a central reason for the situation, in addition of the effects originating in the electrode–semiconductor contacts. The exchange of lattice oxygen with the surrounding atmosphere and a possible diffusion of oxygen through oxygen–vacancy donors in n -type oxides, especially at elevated temperatures, have also strong effects on the behaviour of semiconductor gas sensors. Atomistic understanding of surfaces is the basis for the understanding of both the receptor and transducer functions of semiconductor gas sensors. The rutile structure tin dioxide, SnO 2 , together with its most stable (110) face is the example material here. Especially, we consider the oxygen chemistry at the SnO 2 (110) surface together with its connection to dipole layers and band-gap surface states. For example, the role of tin (II) ions at the reduced SnO 2 (110) surface is discussed. A “transistor model” is also given to describe the transducing properties of semiconductor gas sensors.

The electronic structure of the stoichiometric and reduced SnO2 (110) surfaces is studied with first-principles calculations. Calculations are carried out with two complementary self-consistent ab initio–DFT–GGA methods. Surface relaxation is considered, where the most prominent feature turns out to be the surface layer in-plane oxygen displacement of the reduced surface outwards, about 0.4 A with respect to the surface layer tin atoms. The electronic structure of the relaxed surfaces is considered in terms of atomic orbitals and rehybridization, and the surface band structure. The bands are flat at the stoichiometric surface, but strong dispersion occurs at the reduced surface. The dispersion results in electronic levels into the band gap, which have also been experimentally observed.