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Prospective Study of Human Papillomavirus (HPV) Types, HPV Persistence, and Risk of Squamous Cell Carcinoma of the Cervix

Background: The link between squamous cell cervical carcinoma and human papillomavirus (HPV) 16/18 is well established, but the magnitude of the risk association is uncertain and the importance of other high-risk HPV (HRHPV) types is unclear. Methods: In two prospective nested case-control series among women participating in cytologic screening in Sweden, we collected 2,772 cervical smears from 51

PLIF diagnostics of NO oxidization and OH consumption in pulsed corona discharge

Pulsed corona discharge is an efficient method on NO oxidization, and the investigation of the oxidization process is significant both for model validation and industrial application. In-situ visualization of NO and OH in pulsed corona discharge was performed by planar laser-induced fluorescence (PLIF) in this work. Two dimensional NO oxidization and OH consumption were studied under different con

Sensitivity of catalysis to surface structure: The example of CO oxidation on Rh under realistic conditions

Using a combination of surface x-ray diffraction and mass spectrometry at realistic pressures, the CO oxidation reactivity of Rh(111) and Rh(100) model catalysts has been studied in conjunction with the surface structure. The measurements show that the presence of a specific thin surface oxide is crucial for the high activity of the Rh based CO oxidation. As this oxide is readily formed on all Rh

Oxidation and reduction of Pd(100) and aerosol-deposited Pd nanoparticles

Using in situ high-pressure x-ray photoelectron spectroscopy, we have followed the oxidation and the reduction of Pd model catalysts in oxygen and CO pressures in the millibar range. The study includes a Pd(100) single crystal as well as SiOx-supported Pd nanoparticles of 15 or 35 nm diameter, respectively. We demonstrate that nanoparticles also form ultrathin surface oxides prior to the onset of

Drosophila melanogaster deoxyribonucleoside kinase activates gemcitabine

Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 angstrom resolution structure of DmdNK in complex with gemcitabine shows that the residues Tyr70 and Arg105 play a crucial r

Hydroxyapatite as a novel reversible in situ adsorption matrix for enzyme thermistor-based FIA

The application of the easily available and inexpensive chromatographic matrix hydroxyapatite for reusable and reversible immobilization of enzymes for enzyme thermistor-based flow injection analysis of glucose and Urea was tested. The immobilization was achieved by simple affinity adsorption of glucose oxidase and urease by a suitable pH-induced alteration of the protein charge. A linear detectio

Adsorption of Trimethyl Phosphate on Maghemite, Hematite, and Goethite Nanoparticles

Adsorption of trimethyl phosphate (TMP) on well-characterized hematite, maghemite and goethite nanopartides was studied by in situ DRIFT spectroscopy as a model system for adsorption of organophosphorous (OP) compounds on iron minerals. The iron minerals were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS)

Optimal Migration Strategies in Bats

This paper introduces some theoretical concepts based on optimality theory that may be applied to bat migration. Most predictions are based on flight mechanics and potential flight range. Optimal behavior will depend on the relevant immediate currency, such as safety, time, or energy. Predictions concern optimal flight speeds, stopover duration, fuel load at departure, and the adaptive use of wind

On the H2 Decentralized Controller Synthesis for Delayed Bilateral Teleoperation Systems

Procedure for the synthesis of decentralized controllers for delayed bilateral teleoperation systems is proposed, based on the analytical solution of a global H2 optimization. Explicit state-space formulae for the optimal controller are presented. The controller possesses a neat structure, which preserves closed-loop stability regardless of the delay length. The behavior of the resulting teleopera

A 0.7 to 3 GHz wireless receiver front end in 65-nm CMOS with an LNA linearized by positive feedback

This paper presents a wireless receiver frontend intended for cellular applications implemented in a 65 nm CMOS technology. The circuit features a low noise amplifier (LNA), quadrature passive mixers, and a frequency divider generating 25 % duty cycle quadrature local oscillator (LO) signals. A complementary common-gate LNA is used, and to meet the stringent linearity requirements it employs posit

Epidemiology and the initial presentation of autoimmune hepatitis in Sweden: A nationwide study

Objective. Autoimmune hepatitis (AIH) is a chronic liver disease, which if untreated can lead to cirrhosis and hepatic failure. The aim of the study was to investigate the incidence, prevalence, diagnostic tradition and clinical initial presentation of AIH. Material and methods. Analyses were performed in 473 patients identified as having probable or definite AIH. Results. The incidence of AIH was

Time characteristics of the effect of alcohol cessation on the risk of stomach cancer a meta-analysis

Background: In the Bagnardi et al. (2001) meta-analysis, it was found that alcohol consumption increases the risk of stomach cancer (OR = 1.32 for heavy drinkers). However, it is unknown if drinking cessation reverses this alcohol-elevated risk. Methods: A systematic literature review was performed to provide the information for a meta-analysis where the dose-risk trend was estimated for years sin

Kohn-Sham density functional theory for quantum wires in arbitrary correlation regimes

We use the exact strong-interaction limit of the Hohenberg-Kohn energy density functional to construct an approximation for the exchange-correlation term of the Kohn-Sham approach. The resulting exchange-correlation potential is able to capture the features of the strongly correlated regime without breaking the spin or any other symmetry. In particular, it shows "bumps" (or barriers) that give ris

Calcium mediated interaction of calf-thymus DNA with monolayers of distearoylphosphtidylcholine: a neutron and Xray reflectivity study

X-ray and neutron reflection studies, the latter in conjunction with contrast variation, have been combined to study the interaction of calf thymus DNA (ctDNA) with monolayers of distearoylphosphatidylcholine (DSPC) in the presence of 20 mM Ca2+ ions, at the air–liquid interface as a function of surface pressure (10, 20, 30 and 40 mN m−1). Analysis of the X-ray and neutron reflection data showed t

Use of a trabecular metal implant in ankle arthrodesis after failed total ankle replacement

Patients and methods 13 patients with a migrated or loose total ankle implant underwent arthrodesis with the use of a retrograde intramedullary nail through a trabecular metal Tibial Cone. The mean follow-up time was 1.4 (0.6-3.4) years. Results At the last examination, 7 patients were pain-free, while 5 had some residual pain but were satisfied with the procedure. 1 patient was dissatisfied and e