First Directional Measurement of Sub-MeV Solar Neutrinos with Borexino.

We report the measurement of sub-MeV solar neutrinos through the use of their associated Cherenkov radiation, performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The measurement is achieved using a novel technique that correlates individual photon hits of events to the known position of the Sun. In an energy window between 0.54 to 0.74 MeV, selected using the dominant scintillation light, we have measured 10 887_{-2103}^{+2386}(stat)±947(syst) (68% confidence interval) solar neutrinos out of 19 904 total events. This corresponds to a ^{7}Be neutrino interaction rate of 51.6_{-12.5}^{+13.9} counts/(day·100 ton), which is in agreement with the standard solar model predictions and the previous spectroscopic results of Borexino. The no-neutrino hypothesis can be excluded with >5σ confidence level. For the first time, we have demonstrated the possibility of utilizing the directional Cherenkov information for sub-MeV solar neutrinos, in a large-scale, high light yield liquid scintillator detector. This measurement provides an experimental proof of principle for future hybrid event reconstruction using both Cherenkov and scintillation signatures simultaneously.

Proprioception and isometric muscular strength in haemophilic subjects.

Haemophilia is characterized by intra-articular bleeding, often requiring immobilization, which may result in muscle atrophy and impaired proprioception. The aim of the study was to investigate differences in proprioceptive performance and isometric muscular strength of the lower limbs in haemophilic subjects compared with control subjects. Twelve subjects with severe haemophilia (11 haemophilia A; one haemophilia B) vs. 12 control subjects were matched for anthropometric data and tested for differences of proprioception (one-leg-stand, posturomed, angle-reproduction, and tuning fork tests) and isometric strength (leg press, knee extensor). The static proprioceptive performance of the haemophilic group, as measured by the one-leg-stand test (on hard or soft ground, with open or closed eyes; P < 0.05) was demonstrably impaired (by 41-363%). In contrast, the dynamic proprioceptive performance measured by the posturomed test did not show any difference between the groups. The local proprioceptive performance (angle-reproduction test) of the knee, (the most commonly affected joint in haemophiliacs) showed a trend to impaired function but was not distinctly different from that of controls. The quantitative sensory function (tuning fork) showed significant (P < 0.05) impairment of 9-10% in the haemophilic subjects. Additionally, the isometric muscular strength of the leg extensor was weaker (32-38%) in the haemophilic group when the limbs were tested individually as well as bilaterally (P < 0.05). In conclusion, the results suggest that global proprioceptive performance is impaired and that the isometric strength of the leg extensors is weaker in the haemophilic subjects. Therefore, specialized training for global proprioception would be helpful in order to compensate for proprioceptive deficits. This exercise regimen should also include safe strength-training for an optimal stabilization of the joints, but must be adapted to the individual needs and situations of the haemophilic subjects.p

Clinical sciences and orthopaedics: case report homozygous APC resistance in an elite athlete.

We report the case of a 31 year old female elite athlete. During a routine check-up including a search for hereditary hemostatic risk factors for thrombosis, resistance to activated protein C was detected. Molecular analysis of the factor V gene revealed homozygosity for the factor V Leiden mutation. This is the first documented case of an elite athlete who is a homozygous carrier of factor V Leiden. Elite athletes may be exposed to several circumstantial thrombogenic risk factors and, therefore, special preventive measures in carriers of a congenital risk factor such as APC resistance are indicated. Essential measures are early anticoagulation during periods of immobilisation e.g. after sports-related injuries, a single dose of low-molecular-weight heparin specially for individuals with several thrombotic risk factors and/or leg muscle exercises for long-distance (air) travels and avoiding haemoconcentration with a sufficient oral fluid intake.

APC resistance in an elite female athlete.

In a routine checkup the family history of an elite female mogul skier was found to contain an unusually high number of thrombotic incidents. This prompted us to do diagnostic thrombophilia studies, which revealed a resistance to activated protein C, a heterozygous factor V Leiden disorder. This is the first documented case of APC resistance in an elite female athlete. Since high performance sports are known to carry an increased risk of thrombogenesis, measures to avoid thrombosis or a thromboembolic event must be initiated in case of known APC resistance. Suitable measures are early anticoagulation during periods of immobilization, a single dose of low molecular weight heparin, leg muscle exercises for long distance flights, and avoidance of hemoconcentration with a sufficient oral fluid intake.

Effects on bone mineral density of low-dosed oral contraceptives compared to and combined with physical activity.

A cross-sectional study was designed to examine the influence of exercise compared to and in combination with low-dosed oral contraceptives (OCs) on bone mineral density (BMD). One hundred twenty-eight women (20 to 35 years of age) were assigned to four groups with respect to the years of exercise and OC intake. Influence factors were determined by a detailed questionnaire and interview. BMD for L2-4 and the femoral neck was assessed by DXA. The highest BMD values were found in the group of women characterized by long-term exercise (9.45 +/- 4.32 yr) and short use of OC (1.6 +/- 1.69 yr). No beneficial effect of exercise on BMD was found in the group with a long exercise period (10.4 +/- 4.14 yr) and long-term intake of OC (8.2 +/- 4.14 yr). Differences in mean BMD values between the two groups were significant in all regions assessed (p < 0.05). No differences in mean BMD were found in the groups with short-term exercise but long or brief histories of OC. The question arises as to whether active women taking low-dosed OC at an earlier age will develop an adequate BMD.

[Hemodynamics and ergometric performance modified by low dosage oral contraceptives]. / Hämodynamik und ergometrische Leistung unter Einfluss eines niedrigdosierten oralen Kontrazeptivums.

In this pilot study hemodynamic parameters under base-line and performance conditions during a cycle without (N) and with low-dosed oral contraceptives (OC) were of interest. A group of 6 women (age 23.2 +/- 2.1 years) underwent 8 bicycle ergometry sessions each in both a normal cycle and in a cycle on OC. Testing was done in 3 phases of each cycle. Data were obtained on the maximum watt performance, the pulse work capacity at a heart rate of 170 beats per minute (PWC170), as well as on blood pressure and heart rate at rest and at various levels of exercise. No significant differences were found between the N and OC cycles during the follicular phase or in mid-cycle. During the luteal phase, however, faster heart rates and higher blood pressure levels were found for N cycles than in the corresponding phase under OC (p < 0.05).

Cyclic ovarian function in recreational athletes.

In 17 female recreational athletes, ovarian function was monitored using daily hormone measurements and serial ultrasound determinations. Whereas 11 out of 13 women of a control group showed estradiol (E2) maxima beyond 470 pmol/l, progesterone (P4) maxima of 19 nmol/l or more, and a luteal phase length of 9 days or more, only 10 out of 17 athletes satisfied these criteria. Six athletes showed disturbed follicular development, and one athlete showed luteal phase disturbance. Both athletes with disturbed menstrual function (n = 7) and athletes fulfilling the above-mentioned minimal criteria (n = 10) had lower E2 concentrations in all phases of the menstrual cycle (P less than 0.05). P4 concentrations were significantly decreased in the group with disturbed menstrual function (P less than 0.05). Maximal aerobic capacity in the two athlete groups was similar. Neither athlete group showed the expected increase in caloric intake compared with the sedentary controls. It is concluded that recreational running is associated with altered ovarian function. Inadequate nutritional adaptation may be a contributing factor.

[The echocardiographic diagnosis of mitral-valve prolapse (syndrome of late systolic murmur with click) (author's transl)]. / Klicksyndrom mit sp-5aatsystolischem Geräusch (Mitralk

The clinical diagnosis of mitral-valve prolapse was made in ten patients on the basis of a late systolic murmur with or without a click. In each case the echocardiogram confirmed the diagnosis. In five it was further confirmed by angiocardiography. The late systolic murmur, with or without click, accentuated after nitroglycerin, is characteristic for mitral-valve prolapse.

[Clinical studies on the effect of drugs used in the treatment of angina]. / Klinische Vergleichsstudie über den Effekt der vier koronarwirksamen Hauptsubstanzgruppen

The report is based on a four-centre study on 25 patients with coronary insufficiency (ECG signs). In random sequence the following were given to each patient: a nitrate (isosorbide dinitrate), carbocromene, practolol, and oxyphedrine. The initial criterion for inclusion was S-T depression of 0.2 mV on stepwise exercise (bicycle ergometry). S-T depression, systolic blood pressure and heart rate changes were used as criteria. For each drug there was an acute test and a long-term test of 12 days. The Friedman test was used for the statistical evaluation of the results. Isosorbide dinitrate decreased the extent of S-T depression in the acute tests while practolol did so in the long-term test. Practolol reduced systolic pressure on long-term administration, with no difference in the acute experiment. Heart rate was reduced by practolol both acutely and long-term. These results give no indication for any possible differential treatment of coronary insufficiency, but this may be due to the selection of patients in this study.