Luminosity-independent measurement of the proton-proton total cross section at √s=8 TeV.

The TOTEM collaboration has measured the proton-proton total cross section at √s=8 TeV using a luminosity-independent method. In LHC fills with dedicated beam optics, the Roman pots have been inserted very close to the beam allowing the detection of ~90% of the nuclear elastic scattering events. Simultaneously the inelastic scattering rate has been measured by the T1 and T2 telescopes. By applying the optical theorem, the total proton-proton cross section of (101.7±2.9) mb has been determined, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections: σ(el)=(27.1±1.4) mb; σ(inel)=(74.7±1.7) mb.

Double diffractive cross-section measurement in the forward region at the LHC.

The first double diffractive cross-section measurement in the very forward region has been carried out by the TOTEM experiment at the LHC with a center-of-mass energy of sqrt[s]=7 TeV. By utilizing the very forward TOTEM tracking detectors T1 and T2, which extend up to |η|=6.5, a clean sample of double diffractive pp events was extracted. From these events, we determined the cross section σDD=(116±25) µb for events where both diffractive systems have 4.7<|η|min<6.5.

[S3-Check--evaluation and generation of normal values of a test for balance ability and postural stability]. / S3-Check--Evaluierung und Normwerteerhebung eines Tests zur Erfassung der Gleichgewichtsfähigkeit und Körperstabilität.

INTRODUCTION: Balance is very important in daily living, but there are practically no balance evaluation methods which fulfill scientific criteria and are available to the fitness community and other groups. The aims of this paper are to determine if the MFT-S3-Check, a system to measure balance, is scientifically objective, valid and reliable; and to establish norms for the MFT S 3-Check system. METHODS: Reliability was evaluated with 30 subjects in two testing sessions on two different days. Objectivity was determined by having two different test administrators test 10 subjects. Norms were generated from the data of over 5000 subjects (8 - 70 years of age). Validity was checked by comparing norms to data collected from 758 tests performed on ski racers (10 - 18 years of age). RESULTS: The objectivity and reliability tests for the sensor motor and stability indexes produced correlations which were moderate to very high. Norms were created for all age groups (female, male). The ski racers had significantly better values than the norms. DISCUSSION: The MFT S 3-Check fulfills the scientific criteria and is in use in fitness settings and in physiotherapy.

Leukocyte adhesion--an integrated molecular process at the leukocyte plasma membrane.

Leukocyte adhesion is of pivotal functional importance, because most leukocyte functions depend on cell-cell contact. It must be strictly controlled, both at the level of specificity and strength of interaction, and therefore several molecular systems are involved. The most important leukocyte adhesion molecules are the selectins, the leukocyte-specific beta2-integrins and the intercellular adhesion molecules. The selectins induce an initial weak contact between cells, whereas firm adhesion is achieved through integrin intercellular adhesion molecular binding. Although studies during the past twenty years have revealed several important features of leukocyte adhesion much is still poorly understood, and further work dealing with several aspects of adhesion is urgently needed. In this short essay, we review some recent developments in the field.

Leukocyte adhesion--a fundamental process in leukocyte physiology.

Leukocyte adhesion is of pivotal functional importance. The adhesion involves several different adhesion molecules, the most important of which are the leukocyte beta 2-integrins (CD11/CD18), the intercellular adhesion molecules, and the selectins. We and others have extensively studied the specificity and binding sites in the integrins and the intercellular adhesion molecules for their receptors and ligands. The integrins have to become activated to exert their functions but the possible mechanisms of activation remain poorly understood. Importantly, a few novel intercellular adhesion molecules have been recently described, which seem to function only in specific tissues. Furthermore, it is becoming increasingly apparent that changes in integrins and intercellular adhesion molecules are associated with a number of acute and chronic diseases.

Characterization of beta2 (CD18) integrin phosphorylation in phorbol ester-activated T lymphocytes.

Integrins are transmembrane proteins involved in cell-cell and cell-extracellular-matrix interactions. The affinity and avidity of integrins for their ligands change in response to cytoplasmic signals. This 'inside-out' activation has been reported to occur also with beta2 integrins (CD18). The beta2 integrin subunit has previously been shown to become phosphorylated in T lymphocytes on cytoplasmic serine and the functionally important threonine residues after treatment with phorbol esters or on triggering of T-cell receptors. We have now characterized the phosphorylation of beta2 integrins in T-cells in more detail. When T-cells were activated by phorbol esters the phosphorylation was mainly on Ser756. After inhibition of serine/threonine phosphatases, phosphorylation was also found in two of the threonine residues in the threonine triplet 758-760 of the beta2 cytoplasmic domain. Activation of T-cells by phorbol esters resulted in phosphorylation in only approx. 10% of the integrin molecules. Okadaic acid increased this phosphorylation to approx. 30% of the beta2 molecules, assuming three phosphorylation sites. This indicates that a strong dynamic phosphorylation exists in serine and threonine residues of the beta2 integrins.

Activity-based pacing: comparison of a device using an accelerometer versus a piezoelectric crystal.

The EXCEL VR, an accelerometer-based pacemaker (AC), and the Legend, a pacemaker utilizing a piezoelectric crystal (PZ), were compared under ergometric conditions and during stair climbing to assess the appropriateness of their rate responses. The pacemakers, programmed to the manufacturers' nominal settings in order to compare different technologically based sensors under identical conditions, were strapped over subjects' left mid-pectoral region. Placement of the devices was randomized to control for positional effects. Ten healthy subjects (55-72 years) completed a graded exercise treadmill test to 80% of maximum predicted heart rate (HR). An additional group of ten subjects (50-66 years) completed exercise protocols involving bicycle ergometry and stair climbing. Throughout all tests, pacemaker pulse rates and subjects' intrinsic HR were monitored continuously. For the treadmill exercise, the average correlations between the AC and PZ pacemakers' pulse rate and HR for the group as a whole were r = 0.92 and r = 0.82, respectively. Individual subject comparisons were also made between each pacemaker rate and intrinsic HR. The mean difference from intrinsic rate was 11 ppm for the AC pacemaker and 24 ppm for the PZ pacemaker. In addition, the PZ pacemaker's maximal pulse rate was significantly lower (105 +/- 9.6 ppm) than the other two rates (AC 137 +/- 6 ppm; intrinsic HR 129 +/- 2 beats/min). Throughout the bicycle ergometry testing, the intrinsic HR was higher than the AC and PZ pacing rates. However, the AC's rate was significantly higher than the PZ's rate. When subjects ascended stairs, the intrinsic HR and AC rate were closely correlated, but the PZ rate was significantly lower.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of arterial compliance on diastolic blood pressure and its relation to cardiovascular events.

Reduction of arterial compliance leads to a higher systolic (SBP) and a lower diastolic blood pressure (DBP). The increasing occurrence of reduced arterial compliance is responsible for the steep increase in SBP after the age of 50 years and also for the constancy and later decline in DBP. Reduced arterial compliance will blur the relationship between mean arterial pressure and DBP. This may change the relationships between cardiovascular events and DBP. The possibility of non-causal co-existence of reduced compliance and atherosclerosis is discussed. Such a co-existence would markedly influence the relationship between cardiovascular events and DBP. Finally, the influence that reduced compliance might have on the shape of the relation between cardiovascular episodes and diastolic and systolic blood pressure is discussed.

Increased total mortality and decreased functional capacity are associated with low systolic blood pressure among elderly women.

As part of an epidemiological survey of 75-, 80- and 85-year-old citizens of Copenhagen, the blood pressure of 566 participants was measured at home visits. Based on WHO criteria, systolic hypertension was present in 66% of the men and 71% of the women, and diastolic hypertension was demonstrated in 18% of the men and 22% of the women. The systolic blood pressure was significantly higher among women than among men. Surprisingly, the mortality rate was highest among women with low systolic blood pressure. There was no correlation between blood pressure and morbidity, except among men with low systolic blood pressure, the majority of whom suffered from neoplasms. The women with the lowest systolic blood pressure displayed poor functional capacity in four--and the men in one--out of ten partial functions. No correlation could be demonstrated between blood pressure and intake of medicine. In fact, participants receiving antihypertensives had higher systolic and diastolic blood pressures compared with the other participants.