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Elemental composition of fog interstitial particle size fractions and hydrophobic fractions related to fog droplet nucleation scavenging

The cloud nucleation scavenging process was studied during a joint campaign of the EUROTRAC sub‐project Ground‐based Cloud Experiment. It was found that the particle size has a strong influence on the partitioning of particles between the cloud droplet and the interstitial aerosol reservoirs. A new aerosol sampling unit, the relative humidity processing system, was employed for the extraction of p

Is Super-Fast Broadband Negative? An IV-Estimation of the Broadband Effect on Firms' Sales and Employment Level

This study investigates the relationship between super-fast broadband and firms’ sales and employment level in Sweden. It is important to learn more about this recent technological change and few studies has explored the impact of super-fast broadband on firm outcomes. We use the previous roll-out of second-generation internet access to identify the effect of third-generation internet access. The

Human cancer, the naked mole rat and faunal turnovers

We argue that the human evolutionary heritage with frequent adaptations through geological time to environmental change has affected a trade-off between offspring variability and cancer resistance, and thus favored cancer-prone individuals. We turn the attention to a factor setting the highly cancer-resistant naked mole rat apart from most other mammals: it has remained phenotypically largely unch

Droplet nucleation and growth in orographic clouds in relation to the aerosol population

The formation and development of orographic clouds was studied in a field experiment comprising several measurement sites at a mountain ridge. The influence of the aerosol population present on the cloud microstructure was studied in relation to the dynamics in the cloud formation. Droplet nucleation scavenging was investigated by the introduction of a non-dimensional particle diameter related to

A semiclassical model for quark jet fragmentation

A semiclassical model is presented for the way the energy of a fast quark is transformed into observable hadrons. It reproduces the features of 1+1 dimensional QED (the Schwinger model) concerning a flat rapidity distribution in the central region. It also reproduces results from phenomenological considerations, which, based upon scaling, predict that meson formation in the fragmentation region ca

Vaporisation characteristics and detection limits of ion beam thermography

Analytical properties of the chemical speciation method, Ion beam thermography (IBT), have been investigated. IBT combines the multi-elemental ion beam techniques PIXE, PESA, pNRA and cPESA with thermography. During thermography the sample temperature is gradually increased, causing vaporisation of chemical compounds at specific temperatures and the sample at the same time undergoes analysis by th

Chemical speciation of aerosol samples by ion beam thermography

Ion beam thermography (IBT) is a technique for the determination of chemical compounds. The IBT setup combines the multielemental ion beam techniques PIXE, PESA, pNRA and cPESA with thermography. During thermography the temperature is gradually increased up to the order of 600 °C, causing vaporisation of chemical compounds at specific temperatures. The combination of methods display low detection

The use of PIXE and complementary ion beam analytical techniques for studies of atmospheric aerosols

PIXE is nowadays a routine analytical technique in the study of atmospheric aerosols. If it aspires to continue to be so in the future, it will have to compete with a range of other powerful analytical techniques, and outperform them in some respect. It will be shown how PIXE can indeed play an important role in future studies of atmospheric aerosols. For clarification, two concrete examples will

Skin autofluorescence as a measure of advanced glycation end product levels is associated with carotid atherosclerotic plaque burden in an elderly population

BACKGROUND: Advanced glycation end product is an established risk marker in diabetic vascular disease, but its possible associations with atherosclerosis in a general population are yet to be investigated. We studied the degree of carotid atherosclerosis and its association with skin autofluorescence in an elderly population.METHODS: Carotid ultrasound and skin autofluorescence measurements were p

Experimental cross sections for Bremsstrahlung production by the impact of MeV protons on low-Z targets

The production of continuously distributed X-rays by the impact of protons of 1.9-3.0 MeV for X-ray energies between 4 and 6.5 keV, and 1.9-2.65 MeV for X-ray energies between 1.7 and 4 keV has been investigated. Five different target types have been irradiated: polyethylene, polystyrene, carbon. KaptonTM and MylarTM. The results are presented as absolute cross sections for continuous X-ray produc

On the charge limit for crystallizing particles

The electrical charge limit of crystallizing sodium chloride droplets has been studied. Moderately charged sodium chloride solution droplets were dried to highly charged residual particles. The charge limit was found to be near the Rayleigh charge limit for saturated sodium chloride droplets of the same size as the residual particle. The charge loss was not found to affect the particle size to a d

Characterization of the response function of a Si(Li) detector using an absorber technique

The non-Gaussian response function of a Si(Li) detector has been measured for characteristic Kα X-rays in the energy interval 1.5-8.6 keV using an absorber technique. The method is based on the different response to an attenuating absorber placed in front of the detector for the detector tail as compared to fully absorbed photons in the same position in the spectrum. The shape of the tail of a Kα

Long range aerosol transport in Southern Sweden : An example of multtvariate statistical evaluation methodology

The utilization of multivariate statistical techniques is discussed with emphasis on the rather new method SIMCA, when applied to multielemental data. The procedures of scaling and normalizing are described. The data base used is from a project studying long range aerosol transport to southern Sweden. SIMCA reveals low variability in fine mode elemental composition in southerly air masses being cl

Southern scandinavian aerosol composition and elemental size distribution characteristics dependence on air-mass history

The influence of aerosol long range transport in southern Sweden was investigated from a data base consisting of simultaneous cascade impactor measurements at three sampling stations, two coastal and one inland rural location. The study focused on S and heavy metals determined by particle induced X-ray emission (PIXE) analysis. The influence of local emissions was minimized by eliminating samples

Rescattering effects in the decay of the A1

Rescattering effects in the 3π system in the A1 region are studied with a method, which fulfils unitarity and has the proper analytic structure. Fairly small effects are obtained which confirm the result found in amplitude analyses, neglecting rescattering corrections, that the phases of the JP = 1+ amplitudes vary only very little over the A1 region. Similar results hold for the Q enhancement.

Molecular subtypes applied to a population-based modern cystectomy series do not predict cancer-specific survival

Objectives: To investigate the preoperative prognostic value of molecular subtypes in relation to clinical information, histopathological findings, and molecular markers for patients with bladder cancer treated with radical cystectomy. Patients and methods: After standard preoperative staging, a population-based cohort of 519 patients underwent radical cystectomy between 2006 and 2011. Following

Antibiotic Prophylaxis With Trimethoprim/Sulfamethoxazole Instead of Cloxacillin/Cefotaxime Increases Inguinal Surgical Site Infection Rate After Lower Extremity Revascularization

Due to the consistently high proportion of surgical site infections (SSI) after vascular surgery, a change of prophylactic antibiotic therapy from cloxacillin/cefotaxime to trimethoprim/sulfamethoxazole (TMP-SMX) was conducted in 2016. The study included consecutive patients undergoing lower extremity revascularization due to acute or chronic lower extremity arterial disease. The antibiotic regime