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Antarctica is well known to be highly susceptible to atmospheric and oceanic warming. However, due to the lack of long-term and in situ meteorological observations, little is known about the magnitude of the warming and the meteorological conditions in the intersection region between the Antarctic Peninsula (AP), the West Antarctic Ice Sheet (WAIS) and the East Antarctic Ice Sheet (EAIS). Here we present new stable water isotope data (δ18O, δD, d excess) and accumulation rates from firn cores in the Union Glacier (UG) region, located in the Ellsworth Mountains at the northern edge of the WAIS. The firn core stable oxygen isotopes and the d excess exhibit no statistically significant trend for the period 1980–2014, suggesting that regional changes in near-surface air temperature and moisture source variability have been small during the last 35 years. Backward trajectory modelling revealed the Weddell Sea sector, Coats Land and Dronning Maud Land (DML) to be the main moisture source regions for the study site throughout the year. We found that mean annual δ18O (δD) values in the UG region are negatively correlated with sea ice concentrations (SICs) in the northern Weddell Sea but not influenced by large-scale modes of climate variability such as the Southern Annular Mode (SAM) and the El Niño–Southern Oscillation (ENSO). Only mean annual d-excess values show a weak positive correlation with the SAM. On average annual snow accumulation in the UG region amounts to 0.245 m w.e. a−1 in 1980–2014 and has slightly decreased during this period. It is only weakly related to sea ice conditions in the Weddell Sea sector and not correlated with SAM and ENSO. We conclude that neither the rapid warming nor the large increases in snow accumulation observed on the AP and in West Antarctica during the last decades have extended inland to the Ellsworth Mountains. Hence, the UG region, although located at the northern edge of the WAIS and relatively close to the AP, exhibits rather stable climate characteristics similar to those observed in East Antarctica.

The European Academy of Allergy and Clinical Immunology (EAACI) organized the first European Strategic Forum on Allergic Diseases and Asthma. The main aim was to bring together all relevant stakeholders and decision‐makers in the field of allergy, asthma and clinical Immunology around an open debate on contemporary challenges and potential solutions for the next decade. The Strategic Forum was an upscaling of the EAACI White Paper aiming to integrate the Academy’s output with the perspective offered by EAACI’s partners. This collaboration is fundamental for adapting and integrating allergy and asthma care into the context of real‐world problems. The Strategic Forum on Allergic Diseases brought together all partners who have the drive and the influence to make positive change: national and international societies, patients’ organizations, regulatory bodies and industry representatives. An open debate with a special focus on drug development and biomedical engineering, big data and information technology and allergic diseases and asthma in the context of environmental health concluded that connecting science with the transformation of care and a joint agreement between all partners on priorities and needs are essential to ensure a better management of allergic diseases and asthma in the advent of precision medicine together with global access to innovative and affordable diagnostics and therapeutics.

Background Liver resection is the only curative therapeutic option for intrahepatic cholangiocarcinoma (ICC), but the approach to recurrent ICC is controversial. This study analysed the outcome of liver resection in patients with recurrent ICC. Methods Demographic, radiological, clinical, operative, surgical pathological and follow‐up data for all patients with a final surgical pathological diagnosis of ICC treated in a tertiary referral centre between 2001 and 2015 were collected retrospectively and analysed. Results A total of 190 patients had liver resection for primary ICC. The 1‐, 3‐ and 5‐year overall survival (OS) rates were 74·8, 56·6 and 37·9 per cent respectively. Independent determinants of OS were age 65 years or above (hazard ratio (HR) 2·18, 95 per cent c.i. 1·18 to 4·0; P = 0·012), median tumour diameter 5 cm or greater (HR 2·87, 1·37 to 6·00; P = 0·005), preoperative biliary drainage (HR 2·65, 1·13 to 6·20; P = 0·025) and local R1–2 status (HR 1·90, 1·02 to 3·53; P = 0·043). Recurrence was documented in 87 patients (45·8 per cent). The mean(s.d.) survival time after recurrence was 16(17) months. Independent determinants of recurrence were median tumour diameter 5 cm or more (HR 1·71, 1·09 to 2·68; P = 0·020), high‐grade (G3–4) tumour (HR 1·63, 1·04 to 2·55; P = 0·034) and local R1 status (HR 1·70, 1·09 to 2·65; P = 0·020). Repeat resection with curative intent was performed in 25 patients for recurrent ICC, achieving a mean survival of 25 (95 per cent c.i. 16 to 34) months after the diagnosis of recurrence. Patients deemed to have unresectable disease after recurrence received chemotherapy or chemoradiotherapy alone, and had significantly poorer survival. Conclusion Patients with recurrent ICC may benefit from repeat surgical resection.

Abstract The European Academy of Allergy and Clinical Immunology (EAACI) supports three journals: Allergy, Paediatric Allergy and Immunology as well as Clinical and Translational Allergy. The major goals of EAACI include (i) supporting health promotion in which the prevention of allergy and asthma plays a critical role and (ii) disseminating the knowledge of allergy to all stakeholders including the EAACI junior members. Substantial progress was made in 2018 in the identification of basic mechanisms of atopic dermatitis and urticaria and the translation of these mechanisms into clinics. Many large epidemiologic studies and meta-analyses have been the highlights of the last year.

Abstract The European Academy of Allergy and Clinical Immunology (EAACI) owns three journals: Allergy, Pediatric Allergy and Immunology and Clinical and Translational Allergy. One of the major goals of EAACI is to support health promotion in which prevention of allergy and asthma plays a critical role and to disseminate the knowledge of allergy to all stakeholders including the EAACI junior members. There was substantial progress in 2017 in the identification of basic mechanisms of allergic and respiratory disease and the translation of these mechanisms into clinics. Better understanding of molecular and cellular mechanisms, efforts for the development of biomarkers for disease prediction, novel prevention and intervention studies, elucidation of mechanisms of multimorbidies, entrance of new drugs in the clinics as well as recently completed phase three clinical studies and publication of a large number of allergen immunotherapy studies and metaanalyses have been the highlights of the last year.

Due to recent atmospheric and oceanic warming, the Antarctic Peninsula is one of the most challenging regions of Antarctica to understand in terms of both local- and regional-scale climate signals. Steep topography and a lack of long-term and in situ meteorological observations complicate the extrapolation of existing climate models to the sub-regional scale. Therefore, new techniques must be developed to better understand processes operating in the region. Isotope signals are traditionally related mainly to atmospheric conditions, but a detailed analysis of individual components can give new insight into oceanic and atmospheric processes. This paper aims to use new isotopic records collected from snow and firn cores in conjunction with existing meteorological and oceanic datasets to determine changes at the climatic scale in the northern extent of the Antarctic Peninsula. In particular, a discernible effect of sea ice cover on local temperatures and the expression of climatic modes, especially the Southern Annular Mode (SAM), is demonstrated. In years with a large sea ice extension in winter (negative SAM anomaly), an inversion layer in the lower troposphere develops at the coastal zone. Therefore, an isotope–temperature relationship (δ–T) valid for all periods cannot be obtained, and instead the δ–T depends on the seasonal variability of oceanic conditions. Comparatively, transitional seasons (autumn and spring) have a consistent isotope–temperature gradient of +0.69 ‰ °C−1. As shown by firn core analysis, the near-surface temperature in the northern-most portion of the Antarctic Peninsula shows a decreasing trend (−0.33 °C year−1) between 2008 and 2014. In addition, the deuterium excess (dexcess) is demonstrated to be a reliable indicator of seasonal oceanic conditions, and therefore suitable to improve a firn age model based on seasonal dexcess variability. The annual accumulation rate in this region is highly variable, ranging between 1060 and 2470 kg m−2 year−1 from 2008 to 2014. The combination of isotopic and meteorological data in areas where data exist is key to reconstruct climatic conditions with a high temporal resolution in polar regions where no direct observations exist.

Abstract Background Inhalation exposure to fine and ultrafine particles (UFPs) has been associated with respiratory diseases. However, little is known on the quality, threshold levels and concentration of these particles causing adverse health effects. Methods The impact of occupational exposure to submicrometer and UFPs was assessed in 30 healthy police shooting instructors by clinical investigation, self-assessment questionnaire, sputum and spirometry and compared to a control group. General laboratory chemistry parameters, circulating cytokines (interleukin [IL]-2, IL-4, IL-5, IL-6, IL-8, interferon-gamma [IFN-γ]), and granulocyte macrophage colony-stimulating factor (GM-CSF) in serum were measured. UFP exposure was recorded by Scanning Mobility Particle Sizer. Results Concentrations of submicrometer sized airborne particles (

Marmosets represent an attractive and widely used animal species in biomedical research, and the routine monitoring of female reproductive cycles is often mandatory in the fields of reproductive biology and stem cell research. Today, the established method for the reliable detection of ovulation is the determination of progesterone concentrations from blood samples. This method is based on relatively frequent handling and blood collections; therefore, less invasive alternatives would help to reduce stress on the animals. Here, we investigated whether the core body temperature of marmosets would show a correlation with cycle-dependent hormonal fluctuations, as has been described for humans and other primate species. In particular, the objective was to investigate whether the telemetric recording of core body temperature could replace progesterone measurements as a reliable, less invasive method for the detection of ovulation in these animals. Here we show that the core body temperature parameters in female marmosets were characterized by frequent variations, but they were not related to particular days or phases during the reproductive cycle. Therefore, the recording of core body temperature in our controlled standard experimental setting is not an appropriate method to monitor the reproductive cycle in female marmosets, and cannot replace serum progesterone measurement as a state-of-the-art method.

A radiation and electro-magnetic (EM) field analysis of coaxial-to-microstrip transitions is presented. Radiation is quantified by simulation and measurement of a crosstalk between two Omni-Spectra's transitions using microstrip 'open' calibration standards at different positions. Simulation results are compared to the measured data and good agreement is reported on two different substrates. The evaluation method which is used to analyze quality of the transition and its radiation properties was already developed and verified on a grounded coplanar waveguide (CPWG) transmission line. Results can be used to estimate uncertainty budget of the calibrated measurement with respect to the measured radiation. Results on different substrates show interesting behaviour and can prove useful when choosing suitable substrate for specific test-fixture.

An improvement to the load-pull technique for a large-signal design of a transistor amplifier is proposed. On the contrary to the current load-pull technique – a small-signal pre-matching on the output of the transistor is applied which results in reduced demands on a maximum VSWR of the tuner. This minimizes the launcher radiation in the K band and reduce measurement uncertainty. The proposed method has been verified on a design of 22 GHz large-signal amplifier using a Excelics EPA018A-70 transistor.

The rapid progress in nanoelectronics showed an urgent need for microwave measurement of impedances extremely different from the 50Ω reference impedance of measurement instruments. In commonly used methods input impedance or admittance of a device under test (DUT) is derived from measured value of its reflection coefficient causing serious accuracy problems for very high and very low impedances due to insufficient sensitivity of the reflection coefficient to impedance of the DUT. This paper brings theoretical description and experimental verification of a method developed especially for measurement of extreme impedances. The method can significantly improve measurement sensitivity and reduce errors caused by the VNA. It is based on subtraction (or addition) of a reference reflection coefficient and the reflection coefficient of the DUT by a passive network, amplifying the resulting signal by an amplifier and measuring the amplified signal as a transmission coefficient by a common vector network analyzer (VNA). A suitable calibration technique is also presented.

New antenna matrices for both scalar and vector measurement of microwave interferograms for the frequency 2.45 GHz were developed and used for an analysis of sources of measurement errors. Influence of mutual coupling between individual antennas in an antenna matrix on a measurement of microwave interferograms, particularly on a measurement of interferogram minimum values, was studied. Simulations and measurements of interferograms, proposal of a new calibration procedure and correction method are presented. Influence of differences in radiation patterns of individual antennas of an antenna matrix on a measurement of microwave interferograms was studied as well.

A detailed analysis of the assembly influence on thesmall-signal parameters of a packaged transistor is presented. A newmethod, based on 3D field simulation and mixed-mode scatteringparameters approach is proposed. Differences in scattering parameterscaused by assembly change are computed using the new proposed methodand compared to the standard method based on admittance matrix. Thedifferences, accuracy, error sources and suitability of both methodsare discussed. Results are verified experimentally in microstrip linefor two fundamental assembly changes of a transistor in SOT 343 packagein frequency range 45 MHz - 18 GHz.

A new, seven-state switched perturbation two-port (PTP) for vectorreflection measurement based on scalar measurement only was designedand realized in microstrip structure using PIN diodes. The structurewas experimentally tested by means of vector measurements of differentimpedances in frequency band with relative bandwidth of 2.5 octaves.Good agreement with data obtained using a precise vector networkanalyzer was achieved. The new calibration method for the PTPwas designed and tested on real measured data.

A device mismatch seriously degrades the accuracy of its noisefigure characterization. A new second stage correction technique forhighly mismatched device under test is proposed and compared to thestandard technique. The presented method is based on additional vectormeasurement. It takes into account measuring receiver noise figuredependence on the DUT output mismatch besides an available gaincorrection. Significant accuracy improvement of measured data anddecreased error variation is demonstrated. The suggested method is inprinciple able to eliminate all systematic errors in noise figuremeasurement.

Wide-band vector measurements of transmission structures formed bysolenoids with 2, 4 and 6 turns above ground plane were performed inthe frequency band 45 MHz to 18 GHz. Novel equivalent circuits of thesestructures were designed. The equivalent circuits fit the measured datavery well in the frequency band DC to 11 GHz. Comparison with modelsknown up to now are given.

A viral genetic system was used to map the determinants of the ability of Tomato spotted wilt virus (TSWV) to overcome the R gene (Sw-5) in tomato and the resistance conferred by the nucleocapsid gene of TSWV (N gene) in tobacco. A complete set of reassortant genotypes was generated from TSWV isolates A and D. TSWV-A was able to overcome the Sw-5 gene in tomato and the TSWV N gene in tobacco, whereas TSWV-D was repressed by both forms of resistance. The ability to overcome both forms of resistance was associated with the M RNA segment of TSWV-A (MA). Overcoming the Sw-5 gene was linked solely to the presence of MA, to overcome the TSWV N gene was modified by the L RNA and the S RNA of TSWV-A, which is consistent with previous reports that suggest that the nucleocapsid gene is not the primary determinant for overcoming the nucleocapsid-mediated resistance. Sequence analysis of the M RNA segment of TSWV-A, -D, and the type isolate BR-01 revealed multiple differences in the coding and noncoding regions, which prevented identification of the resistance-breaking nucleotide sequences.

In the present study, the applicability of crystalline bacterial cell-surface layers (Slayers) as novel immobilization matrices and reaction zones for dipstick-style immunoassays was investigated. For this purpose, S-layer-carrying cell-wall fragments from Bacillus sphaericus CCM 2120 were deposited on a microporous support, and the Slayer protein was cross-linked with glutaraldehyde. For developing appropriate test systems, either human IgG was directly linked to the carboxylic acid groups from the S-layer protein or it was immobilized using Protein A or, after biotinylation, using streptavidin. A clear correlation was obtained between the amount of anti-human IgG applied and the absorbance values in the immunoassays. S-layers with covalently bound recombinant major birch pollen allergen were used for quantitative and semiquantitative determination of an antibody raised against it. Using S-layers as an immobilization matrix in comparison to amorphous polymers has advantages in that the closed monolayers of functional macromolecules on their outermost surface allows for strong signals in immunoassays, almost completely eliminates background and prevents diffusion.

New circuit component, active resonator, is proposed for use inmicrowave and millimetrewave circuits. It consists of a commonresonator and an amplifier, compensating for losses in the resonator.Properly designed, such an arrangement behaves as a (passive) resonatorwith dramatically increased quality factor. High quality factors can beachieved even at millimetrewave frequencies, where common resonatorssuffer from losses due to small skin depths. Viability of the componentis experimentally verified at microwave region using a TE01 dielectricresonator and an oscillator.

A novel method for vector scattering parameter measurement is presented. The method is based on scalar (SWR) measurement only. Vector data is obtained using a controlled perturbation two-port (CPTP). The method promises broadband operation and cost-effectiveness for both reflection and transmission measurements. Design considerations for CPTP synthesis are presented.

Radiofrequency and microwave CAD computer programs enabling for signal and yield analysis and circuit optimization have been developed. Program is used both in circuit design and student education.