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1.
J Sports Sci ; 40(12): 1412-1425, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35640049

ABSTRACT

This study describes an approach to evaluate the off-ball behaviour of attacking players in association football. The aim was to implement a defensive pressure model to examine an offensive player's ability to create separation from a defender using 1411 high-intensity off-ball actions including 988 Deep Runs (DRs) DRs and 423 Change of Directions (CODs). Twenty-two official matches (14 competitive matches and 8 friendlies) of the German National Team were included in the research. To validate the effectiveness of the pressure model, each pass (n = 25,418) was evaluated for defensive pressure on the receiver at the moment of the pass and for the pass completion rate (R = -.34, p < .001). Next, after assessing the inter-rater reliability (Fleiss Kappa of 80 for DRs and 78 for CODs), three expert raters annotated all DRs and CODs that met the pre-set criteria. A time-series analysis of each DR and COD was calculated to the nearest 0.1 second, finding a slight increase in pressure from the start to the end of the off-ball actions as defenders re-established proximity to the attacker after separation was created. A linear mixed model using run type (DR or COD) as a fixed effect with the local maximum as a fixed effect on a continuous scale resulted in p < 0.001, d = 4.81, CI = 0.63 to 0.67 for the greatest decrease in pressure, p < 0.001, d = 0.143, CI = 9.18 to 10.61 for length of the longest decrease in pressure, and p < 0.001, d = 1.13, CI = 0.90 to 1.11 for the fastest rate of decrease in pressure. As these values pertain to the local maximum, situations with greater starting pressure on the attacker often led to greater subsequent decreases. Furthermore, there was a significant (p < .0001) difference between offensive and defensive positions and the number of off-ball actions. Results suggest the model can be applied to quantify and visualise the pressure exerted on non-ball-possessing players. This approach can be combined with other methods of match analysis, providing practitioners with new opportunities to measure tactical performance in football.


Subject(s)
Athletic Performance , Soccer , Humans , Linear Models , Reproducibility of Results
2.
Med Klin Intensivmed Notfmed ; 116(8): 687-693, 2021 Nov.
Article in German | MEDLINE | ID: mdl-33006639

ABSTRACT

INTRODUCTION: The emergency department (ED) is the main port of entry for patients with infectious diseases, the place where a number of diagnostic procedures are performed and treatment is often initiated. The aim of this retrospective study was to estimate the influence of the establishment and introduction of a blood culture standard operating procedure (BC-SOP) and of the subsequent training of microbial diagnostics in an ED. METHODS: In a before and after study over a study period of 3 months each (November 2017-January 2018 and November 2018-January 2019), the number of blood cultures taken, the rate of blood cultures per 1000 patients, the number of positive blood cultures and the frequency of typical skin pathogens were evaluated. In the interim time between the two study periods, a BC-SOP was developed in collaboration with the hospital's antibiotic stewardship team and subsequently introduced with staff training in the ED. The study was approved by the local ethics committee of the medical faculty of the Heinrich Heine University (2019-392-RetroDEuA). RESULTS: In total 92% of the nursing personnel and 93% of the medical personnel received training. The total number of blood cultures increased from 1757 to 2872 (64% increase) and the rate of blood cultures per 1000 patients from 287 to 481 (68% increase). The number of positive blood cultures decreased from 18.6% to 13.7% (p < 0.05). Typical skin pathogens were found in 34.4% and 26.4% of the cases, respectively (p < 0.05). CONCLUSION: The development, introduction and training of a BC-SOP in the ED can make a relevant contribution to the microbial diagnostics and increase the quantity as well as the quality.


Subject(s)
Antimicrobial Stewardship , Blood Culture , Emergency Service, Hospital , Humans , Retrospective Studies
3.
Phys Rev Lett ; 112(7): 072501, 2014 Feb 21.
Article in English | MEDLINE | ID: mdl-24579591

ABSTRACT

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A=124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

4.
Opt Lett ; 32(15): 2257-9, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17671602

ABSTRACT

We have measured the phase structure of a glass wedge with single photons and biphotons in a Mach-Zehnder interferometer using parametric downconverted light from a Hong-Ou-Mandel particle interferometer as the source. By scanning the wedge through the focus of a microscope objective we find a doubling of the period of the interference pattern in the coincidence counts for biphotons compared to the single-photon experiment. We compare our measurement setup with classical ones and discuss some of the problems of superresolution in quantum lithography.

5.
Phys Rev Lett ; 90(11): 115501, 2003 Mar 21.
Article in English | MEDLINE | ID: mdl-12688938

ABSTRACT

Addition of a low concentration of a very long (430 kg/mol) side group liquid crystal polymer is shown to produce dramatic changes in the flow characteristics of a calamitic nematic liquid crystal. This polymer causes a typical flow-aligning nematic liquid crystal to align near the velocity gradient direction rather than near the velocity direction, corresponding to having a tumbling parameter lambda<-1, for concentrations greater than 7.5% polymer. Such flow-aligning behavior has not been reported previously in a calamitic nematic. The large molecular weight of the present polymer relative to those examined in the prior literature is responsible for these new phenomena.

6.
Biotechniques ; 32(1): 142-4, 146, 148-51, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11808688

ABSTRACT

A novel tissue culture system has been developed that supports the multilayer growth of Hep G2 cells. The system consists of growing cells on collagen-coated perfluorocarbon substrata in the wells of a multi-well plate designed so that, even at very high densities, the oxygen in the cultures is replenished as rapidly as it is consumed. Hep G2 cells, which are typically contact inhibited, grow to form more than 10 layers of cells that continue to secrete albumin. Both multilayer growth and high rates of albumin depend on using a very enriched nutrient medium, compared to media usually used for monolayer culture of Hep G2 cells. The role played by increased oxygenation, enriched media, and the unique properties of the perfluorocarbon substrata for the 3-D growth of anchorage-dependent cells is discussed.


Subject(s)
Cell Division , Fluorocarbons , Animals , Cell Adhesion , Cell Line , Collagen
7.
Anal Chem ; 68(11): 1948-53, 1996 Jun 01.
Article in English | MEDLINE | ID: mdl-8686916

ABSTRACT

Antibody-mimicking synthetic polymers, selective for various optically active amino acid derivatives and peptides, were prepared by noncovalent molecular imprinting. A novel approach, in which the branched, trifunctional cross-linkers pentaerythritol triacrylate and 2,2-bis(hydroxymethyl)butanol trimethacrylate were copolymerized with methacrylic acid, is described. The polymers were subsequently applied as chiral stationary phases in high-performance liquid chromatography. They were superior to previously reported noncovalent molecularly imprinted polymers used for chiral separations in that they showed considerably higher load capacity, increased selectivity, and better resolving capability.


Subject(s)
Antibodies/chemistry , Polymers/chemistry , Amino Acid Sequence , Chromatography, High Pressure Liquid , Molecular Sequence Data
8.
Opt Lett ; 21(7): 450-2, 1996 Apr 01.
Article in English | MEDLINE | ID: mdl-19865435

ABSTRACT

The temporal profiles of the emission from titania particle suspensions in Rhodamine 640 perchlorate dye solutions excited by 10-ps pulses of 527-nm radiation were measured over a wide range of particle and dye concentrations and laser powers. The dynamics of stimulated emission from random media is modeled by a random walk of photons within the colloid and rate equations for molecular excitations. The pulse width and the dependence of the threshold for laser action on dye and scatter concentration are computed by a Monte Carlo simulation of the model and are found to be in qualitative agreement with experiment.

9.
J Chromatogr A ; 691(1-2): 317-23, 1995 Feb 03.
Article in English | MEDLINE | ID: mdl-7894656

ABSTRACT

Stationary phases, to be used in high-performance liquid chromatography, were tailor-made for the separation of amino acids, peptides and proteins. The stationary phases were prepared by molecular imprinting, applying two different approaches. Low-molecular-mass compounds were imprinted in bulk polymers by copolymerization of functional monomers and cross-linkers in the presence of the compound of interest, the print molecule. These polymers were, after extraction of the print molecule, successfully applied as chiral stationary phases, showing high resolution and load capacity. The development of a surface-imprinting approach for the preparation of stationary phases selective for proteins is also discussed.


Subject(s)
Amino Acids/isolation & purification , Chromatography, High Pressure Liquid/methods , Peptides/isolation & purification , Proteins/isolation & purification , Amino Acid Sequence , Fluorenes , Formic Acid Esters , Hydrogen Bonding , Molecular Sequence Data , Polymers , Stereoisomerism
10.
J Mol Recognit ; 8(1-2): 35-9, 1995.
Article in English | MEDLINE | ID: mdl-7598950

ABSTRACT

An adsorbent showing enhanced selectivity for the enzyme RNase A was prepared by a surface imprinting procedure based on metal coordination. A metal chelating monomer, N-(4-vinyl)-benzyl iminodiacetic acid, was polymerized onto methacrylate-derivatized silica particles in the presence of RNase A and metal ions. Lysozyme and RNase A were separated on the adsorbent used as stationary phase in high-performance liquid chromatography.


Subject(s)
Muramidase/isolation & purification , Ribonuclease, Pancreatic/chemistry , Ribonuclease, Pancreatic/isolation & purification , Adsorption , Animals , Cattle , Chelating Agents/chemical synthesis , Chromatography, High Pressure Liquid , Imino Acids/chemical synthesis , Magnetic Resonance Spectroscopy , Protein Conformation , Styrenes/chemical synthesis , Surface Properties
11.
Int J Pept Protein Res ; 44(6): 603-6, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7705983

ABSTRACT

Highly crosslinked synthetic polymers, selective for various N alpha-protected amino acids and derivatives, were prepared by non-covalent molecular imprinting. Methacrylic acid and ethylene glycol dimethacrylate were copolymerized in the presence of the print molecules, which were subsequently extracted from the polymers. The recognition of the polymers for the print molecules and molecules of similar structures was investigated by using the polymers as stationary phases in HPLC. The functional groups of the print molecules interact via hydrogen bonds with the positioned carboxyls of the polymer. It was shown that the N alpha-protecting group, the C alpha-protecting group and the amino acid side chain are also recognized by the binding sites in the polymer.


Subject(s)
Amino Acids/chemistry , Polymers/chemistry , Binding Sites
12.
Opt Lett ; 19(23): 1919-21, 1994 Dec 01.
Article in English | MEDLINE | ID: mdl-19855695

ABSTRACT

Scanning microscopy in combination with an interferometric correlation technique that uses short light pulses or broadband cw light is shown to permit enhanced depth discrimination, which is particularly useful for imaging through thick layers introducing spherical aberration and through scattering media.

13.
Phys Rev A ; 48(6): 4721-4729, 1993 Dec.
Article in English | MEDLINE | ID: mdl-9910181
14.
J Mol Recognit ; 6(1): 25-9, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8251189

ABSTRACT

Novel molecularly imprinted polymer systems utilizing 4-vinylpyridine and 1-vinylimidazole as functional monomers have been developed for enantioselective recognition of carboxylic and N-protected amino acids. Non-covalent interactions between the functional monomers and the template molecules were the source of the subsequent recognition sites in the resultant polymers. The capacity of the polymers for molecular recognition was investigated by using them as stationary phases in the HPLC mode. Polymers prepared with 4-vinylpyridine were found to be more efficient in racemic resolution than those prepared with 1-vinylimidazole. When applying a racemic mixture of the template molecule, the polymers showed highest affinity for the enantiomer used as template. Imprints of a racemic template molecule, as expected, did not exhibit enantioselectivity. The optimal molar ratio of 4-vinylpyridine to the template Cbz-L-Asp-OH in the polymerization mixture was determined to be 12:1. In addition to enantioselectivity, the investigated polymers demonstrated 'ligand selectivity', e.g., a Cbz-L-Asp-OH-imprinted polymer was able to separate Cbz-D,L-Asp-OH, but was unable to separate Cbz-D,L-Glu-OH.


Subject(s)
Imidazoles/chemistry , Polymers/chemical synthesis , Pyridines/chemistry , Stereoisomerism , Chromatography, High Pressure Liquid , Templates, Genetic
15.
Opt Lett ; 18(2): 137-9, 1993 Jan 15.
Article in English | MEDLINE | ID: mdl-19802063

ABSTRACT

Focusing of ultrashort light pulses with single lenses is analyzed by taking into account the unavoidable interplay between chromatic and spherical aberration simultaneously for the first time to our knowledge. The spatial intensity distribution is mainly affected by spherical aberration, whereas the temporal distribution is determined by both aberrations. The impact on second-harmonic generation for femtosecond pulse measurements is discussed. For example, the presence of spherical aberration allows one to record the correct autocorrelation of a 10-fs pulse even if chromatic aberration alone would cause a half-width of the autocorrelation function of 40 fs.

17.
Int J Pept Protein Res ; 35(2): 147-52, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2403410

ABSTRACT

The enzymatic synthesis of dipeptide units of the D-D-configuration in aqueous media, catalysed by muramoyl-pentapeptide carboxypeptidase (E.C.3.4.17.8), is described. Ac-L-Lys(Ac)-D-Ala-D-Lac-OH and Ac-D-Ala-OMe were used as acyl-components. Neutral, basic, and hydrophobic amino acids acting as nucleophiles were incorporated. The enzyme is stereospecific in that only the D-enantiomers of amino acids or amino acid derivatives were incorporated. As nucleophiles, the unmodified amino acids resulted in higher product yields compared with using the corresponding amino acid derivatives. Product yields ranged from 40 to 87%.


Subject(s)
Dipeptides , Muramoylpentapeptide Carboxypeptidase , Amino Acid Sequence , Cephalosporins , Chemical Phenomena , Chemistry , Hydrolysis , Molecular Sequence Data , Penicillin G , Solvents , Stereoisomerism
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