First direct observation of two protons in the decay of 45Fe with a time-projection chamber

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

Effect of a triaxial nuclear shape on proton tunneling: the decay and structure of 145Tm

Gamma rays deexciting states in the proton emitter 145Tm were observed using the recoil-decay tagging method. The 145Tm ground-state rotational band was found to exhibit the properties expected for an h{11/2} proton decoupled band. In addition, coincidences between protons feeding the 2{+} state in 144Er and the 2{+}-->0{+} gamma-ray transition were detected, the first measurement of this kind, leading to a more precise value for the 2{+} excitation energy of 329(1) keV. Calculations with the particle-rotor model and the core quasiparticle coupling model indicate that the properties of the pi{11/2} band and the proton-decay rates in 145Tm are consistent with the presence of triaxiality with an asymmetry parameter gamma approximately 20 degrees .

Endovaskuläre Therapie eines infrarenalen Aortenaneurysmas bei heterotopem Nierentransplantat

INTRODUCTION

The indications for endovascular aortic aneurysm repair (EVAR) are mainly established in hostile abdomen, in patients with significant comorbidities which affect the general operability of the patient and, given the necessary infrastructure, also in ruptured aneurysm. Along to those, we present another possible indication in the presence of a kidney allograft in patients with aortic aneurysm.

METHODS

Based on a case report of aorto-biiliac stent-graft repair of an infrarenal aortic aneurysm in a patient with renal allograft, a systematic review of the literature was performed of all similar cases concerning surgical therapy in this constellation.

RESULTS

EVAR was performed using an aorto-biiliac system (Zenith) Trifab, COOK) in a 61-year-old male patient 11 years after heterotopic renal allotransplantation in the right iliac fossa. Preoperative renal function was normal. Because the donor renal artery was anastomosed to the recipient's external iliac artery the stent-graft was implanted from the left common femoral artery to minimize temporary allograft ischemia. The intra- and postoperative course was uneventful with a follow-up of presently 12 months. A primary type-II endoleak (retroleak from a lumbar artery) is being treated conservatively so far with embolization being a future option. At present there are 15 cases of EVAR in renal allograft patients that have been reported, all of them being successful.

DISCUSSION

All data existing in the literature reported to date as well as our own experience justify the first choice of EVAR in morphologically suitable cases. One major advantage of EVAR in this constellation is the avoidance of aortic cross clamping which poses the graft at risk of ischemia. Long-term results will be most important for definite assessment of EVAR. However, contrast media application during the operation and for CT surveillance should be considered as a major disadvantage.

Ramsey method of separated oscillatory fields for high-precision penning trap mass spectrometry

Ramsey's method of separated oscillatory fields is applied to the excitation of the cyclotron motion of short-lived ions in a Penning trap to improve the precision of their measured mass values. The theoretical description of the extracted ion-cyclotron-resonance line shape is derived and its correctness demonstrated experimentally by measuring the mass of the short-lived 38Ca nuclide with an uncertainty of 1.1 x 10(-8) using the Penning trap mass spectrometer ISOLTRAP at CERN. The mass of the superallowed beta emitter 38Ca contributes for testing the theoretical corrections of the conserved-vector-current hypothesis of the electroweak interaction. It is shown that the Ramsey method applied to Penning trap mass measurements yields a statistical uncertainty similar to that obtained by the conventional technique but 10 times faster. Thus the technique is a new powerful tool for high-precision mass measurements.

First observation of 54Zn and its decay by two-proton emission

The nucleus 54Zn has been observed for the first time in an experiment at the SISSI/LISE3 facility of GANIL in the quasifragmentation of a 58Ni beam at 74.5 MeV/nucleon in a (nat)Ni target. The fragments were analyzed by means of the ALPHA-LISE3 separator and implanted in a silicon-strip detector where correlations in space and time between implantation and subsequent decay events allowed us to generate almost background free decay spectra for about 25 different nuclei at the same time. Eight 54Zn implantation events were observed. From the correlated decay events, the half-life of 54Zn is determined to be 3.2(+1.8)(-0.8) ms. Seven of the eight implantations are followed by two-proton emission with a decay energy of 1.48(2) MeV. The decay energy and the partial half-life are compared to model predictions and allow for a test of these two-proton decay models.

Precise mass measurement of 68Se, a waiting-point nuclide along the rp process

Mass measurements of 68Ge, 68As, and 68Se have been obtained with the Canadian Penning Trap mass spectrometer. The results determine the mass excess of 68Se as -54 232(19) keV, the first measurement with a precision and reliability sufficient to address the light-curve and energy output of x-ray bursts as well as the abundances of the elements synthesized. Under typical conditions used for modeling x-ray bursts, 68Se is found to cause a significant delay in the rp process nucleosynthesis.

New shape isomer in the self-conjugate nucleus 72Kr

A new isomeric 0(+) state was identified as the first excited state in the self-conjugate (N=Z) nucleus 72Kr. By combining for the first time conversion-electron and gamma-ray spectroscopy with the production of metastable states in high-energy fragmentation, the electric-monopole decay of the new isomer to the ground state was established. The new 0(+) state is understood as the band head of the known prolate rotational structure, which strongly supports the interpretation that 72Kr is one of the rare nuclei having an oblate-deformed ground state. This observation gives in fact the first evidence for a shape isomer in a N=Z nucleus.

Two-proton radioactivity of 45Fe

In an experiment at the SISSI-LISE3 facility of GANIL, the decay of the proton drip line nucleus 45Fe has been studied. Fragment-implantation events have been correlated with radioactive decay events in a 16x16 pixel silicon-strip detector. The decay-energy spectrum of 45Fe implants shows a distinct peak at (1.14+/-0.04) MeV with a half-life of T(1/2)=(4.7(+3.4)(-1.4)) ms. None of the events in this peak is in coincidence with beta particles. For a longer correlation interval, daughter decays of the two-proton daughter 43Cr can be observed after 45Fe implantation. The decay energy for 45Fe agrees nicely with several theoretical predictions for two-proton radioactivity.

Excess triiodothyronine as a risk factor of coronary events

BACKGROUND

Abnormalities in cardiac function, eg, arrhythmias and congestive heart failure, often accompany thyrotoxicosis. A relationship between thyroid hormone excess and the cardiac complications of angina pectoris and myocardial infarction (MI) remains largely speculative.

METHODS

The results of thyroid function studies on blood samples drawn from a total of 1049 patients (aged 40 years or older) immediately on emergency medical admission were related to frequencies of angina pectoris and myocardial infarction as determined according to current diagnostic algorithms. After 3 years, those patients who had initially presented with angina pectoris or acute MI were observed for subsequent coronary events; of these (n=185), 98% of the subjects (n=181) could be reevaluated.

RESULTS

On hospital admission, the relative rate of angina pectoris and MI was markedly high (odds ratio, 2.6; 95% confidence interval, 1.3-5.2; P=.007) in patients with elevated serum free and total triiodothyronine (T(3)) levels. An initially elevated free T(3) level was a risk factor for subsequent coronary events during the 3-year follow-up (adjusted odds ratio, 4.8; 95% confidence interval, 1.3-17.4; P=.02).

CONCLUSIONS

An elevation of serum free T(3) levels at hospital admission is associated with a 2.6-fold greater likelihood of the presence of a coronary event. Moreover, an initially elevated T(3) level is associated with a 3-fold higher risk of developing a subsequent coronary event during the next 3 years. Excess T(3) seemed to be a factor associated with the development and progression of acute myocardial ischemia.

Discovery of doubly magic 48Ni

In an experiment at the SISSI/LISE3 facility of GANIL, we used the projectile fragmentation of a primary 58Ni26+ beam at 74.5 MeV/nucleon with an average current of 3 &mgr;A on a natural nickel target to produce very neutron-deficient isotopes. In a 10-day experiment, 287 42Cr isotopes, 53 45Fe isotopes, 106 49Ni isotopes, and 4 48Ni isotopes were unambiguously identified. The doubly magic nucleus 48Ni, observed for the first time, is the most proton-rich isotope ever identified with an isospin projection T(z) = -4. It is probably the last doubly magic nucleus with "classical" shell closures accessible for present-day facilities. Its observation allows us to deduce a lower limit for the half-life of 48Ni of 0.5 &mgr;s.

One-neutron knockout from individual single-particle states of 11Be

The structure of the halo nucleus 11Be has been studied using the reaction 9Be(11Be,10Be+gamma)X at 60 MeV/nucleon. The ground state structure of 11Be is determined by comparing the experimental cross sections to a calculation combining spectroscopic factors from the shell model with l-dependent single-particle cross sections obtained in an eikonal model. This experiment shows the dominant 1s single-particle character of the 11Be ground state and indicates a small contribution of 0d admixture in the wave function. After correction for the approximately 22% intensity to excited levels, a clean and precise distribution of parallel momentum for knockout from the 1s halo wave function is obtained for the first time.

Once daily controlled versus immediate release oxybutynin chloride for urge urinary incontinence. OROS Oxybutynin Study Group

PURPOSE

We compared the efficacy and safety of once daily controlled and immediate release oxybutynin for incontinence.

MATERIALS AND METHODS

This multicenter, randomized, double-blind, active control, parallel study was designed to evaluate urge urinary incontinence episodes using a 7-day diary.

RESULTS

A total of 97 women and 8 men 34 to 76 years old with urge incontinence or mixed incontinence with a clinically significant urge component were enrolled in the study. The number of weekly urge incontinence episodes decreased from 27.4 to 4.8 after controlled and from 23.4 to 3.1 after immediate release oxybutynin (p = 0.56), and total incontinence episodes decreased from 29.3 to 6 and from 26.3 to 3.8, respectively (p = 0.6). Weekly urge incontinence episodes from baseline to end of study also decreased to 84% after controlled and 88% after immediate release oxybutynin (p = 0.7). Continence was achieved in 41% of the controlled and 40% of the immediate release group (p = 0.9). Dry mouth of any severity was reported by 68 and 87% of the controlled and immediate release groups, respectively (p = 0.04), and moderate or severe dry mouth occurred in 25 and 46%, respectively (p = 0.03).

CONCLUSIONS

Participants taking a single daily does of controlled release oxybutynin had similar reductions in urge incontinence and total incontinence episodes compared to those taking oxybutynin 1 to 4 times daily. A lower incidence of dry mouth was reported for controlled release oxybutynin.

Does the measurement of digital arterial pressure using the Doppler ultrasonic technique without testing for vasospasm to detect digital arterial occlusions make good sense?

BACKGROUND

An attempt was made to determine whether measurement of the systolic pressure with the Doppler ultrasonic technique can be used to detect occlusions of the digital arteries.

PATIENTS AND METHODS

A total of 92 patients (44 women, 48 men) with an average age of 47.5 years (range: 19-82 years) were investigated. Of these, 17 were diagnosed with a primary Raynaud's syndrome, 45 with a secondary, and 5 patients with a suspected secondary Raynaud's syndrome; 25 patients had digital occlusions of varying genesis. In all patients, the Doppler ultrasonic technique was applied to measure the systolic pressure of the digital arteries of both hands at a room temperature of 21-24 degrees Celsius without any additional thermal (warm or cold) provocation or use of vasodilatory agents; the results obtained were compared with arteriographs of the hands.

RESULTS

While the sensitivity of the Doppler ultrasonic technique was a very low 55%, the specificity was a very high 95%. With a prevalence of 68%, the positive predictive value was 96%, the negative predictive value 50%. In the case of angiographically patent digital arteries with no spastic narrowing, the Doppler ultrasonic-measured systolic pressure was up to 30 mmHg above, and up to 25 mmHg below, the systolic pressure measured in the ipsilateral brachial artery. A pressure gradient between upper arm and digital arteries of this order of magnitude therefore does not exclude pathological changes. Only angiography was able reliably to detect vascular stenoses and occlusions.

CONCLUSION

Reliable exclusion of digital arterial occlusions using the Doppler ultrasonic technique without testing for vasospasm is not possible. Only occlusions of digital arteries together with simultaneous occlusions of hand arteries can be reliably detected. Owing to the considerable scatter of the systolic blood pressure gradient between brachial and digital arteries, the Doppler ultrasonic technique cannot be used to distinguish between patent and occluded digital arteries without the use of additional vasodilation.

A new macromolecular oscillation camera at CHESS

Increasing X-ray flux and decreasing crystal size are two factors placing new demands on macromolecular diffraction cameras at synchrotrons. A new oscillation camera with high mechanical precision and fast rotation speed is described.

Colour coded duplex sonography in ischemic finger artery disease--a comparison with hand arteriography

BACKGROUND

A reliable non-invasive diagnostic procedure is desirable to exclude arterial pathology in patients with pain in their fingers.

PATIENTS AND METHODS

The results of colour coded duplex sonography (CCDS) in 450 finger arteries (45 hands/41 patients) were compared with findings obtained by intra-arterial digital subtraction arteriography (i.a.-DSA). The population consisted of symptomatic patients with a high risk for finger artery pathologies.

RESULTS

Arteriography of the hand documented finger artery occlusion in 35.6% of these patients. CCDS is capable of detecting pathological alterations in finger arteries with high accuracy and can differentiate them from regular arteries. In patients with several diseases of the finger arteries, the ultrasound diagnosis concurred with arteriography in 93.1% of patent arteries. In patients with occluded arteries the accuracy of CCDS was 86.3%.

CONCLUSION

When assessing diseases of finger arteries non-invasive CCDS should be used routinely before referring the patient to arteriography. The latter is only indicated when there is a need to image the whole arterial trunk of the upper extremity or the hand, or in case of equivocal results of CCDS.

Stiff-person syndrome with anti-glutamic acid decarboxylase autoantibodies: complete remission of symptoms after intrathecal baclofen administration

A female patient, aged 61 years, who developed a severe immobilizing stiff-person syndrome in conjunction with insulin-dependent diabetes mellitus, is described. In addition to the typical clinical symptoms, diagnosis was proven by the presence of autoantibodies against glutamic acid decarboxylase in serum and cerebrospinal fluid. Symptomatic treatment with continuous intrathecal application of baclofen administered by a subcutaneous pump resulted in rapid clinical improvement so that the patient became ambulatory. Intermittent withdrawal from intrathecal baclofen therapy led to complete remanifestation of stiff-person syndrome within 18 h; after re-introduction of intrathecal therapy stiffness disappeared completely within 48 h. The clinical course has been stable now for over 24 months and stiffness has completely disappeared. The effect of baclofen in this patient is discussed in the light of the suggested pathophysiological mechanisms in stiff-person syndromes.

[Color-coded duplex ultrasound of lower leg arteries--image reliability with reference to Fontaine stages]

We examined the accuracy of colour flow detection of lower limb arteries in relation to Fontaine's criteria of obstructed peripheral circulation. Assessments were conducted in relation to stages I and II as well as to stages III and IV and compared to the corresponding i. a.-DSA: On comparing the total of all ultrasound results in stages (I-IV) with those of arteriography (92 calf arteries) we found a sensitivity between 80 and 90% and a specificity between 90 and 97%. Results did not differ from these values in the subgroups Fontaine II-IV. Especially in the stages III/IV in comparison to stage II we could not find any disadvantages of colour coded vessel imaging. With sufficient reliability we succeeded in demonstrating calf arteries in endangiitis (Bürger's disease) and in diabetics with mediasclerosis.