Granular aluminium nanojunction fluxonium qubit.

Mesoscopic Josephson junctions, consisting of overlapping superconducting electrodes separated by a nanometre-thin oxide layer, provide a precious source of nonlinearity for superconducting quantum circuits. Here we show that in a fluxonium qubit, the role of the Josephson junction can also be played by a lithographically defined, self-structured granular aluminium nanojunction: a superconductor-insulator-superconductor Josephson junction obtained in a single-layer, zero-angle evaporation. The measured spectrum of the resulting qubit, which we nickname gralmonium, is indistinguishable from that of a standard fluxonium. Remarkably, the lack of a mesoscopic parallel plate capacitor gives rise to an intrinsically large granular aluminium nanojunction charging energy in the range of tens of gigahertz, comparable to its Josephson energy. We measure coherence times in the microsecond range and we observe spontaneous jumps of the value of the Josephson energy on timescales from milliseconds to days, which offers a powerful diagnostics tool for microscopic defects in superconducting materials.

Field-effect silicon-plasmonic photodetector for coherent T-wave reception.

Plasmonic internal photoemission detectors (PIPED) have recently been shown to combine compact footprint and high bandwidth with monolithic co-integration into silicon photonic circuits, thereby opening an attractive route towards optoelectronic generation and detection of waveforms in the sub-THz and THz frequency range, so-called T-waves. In this paper, we further expand the PIPED concept by introducing a metal-oxide-semiconductor (MOS) interface with an additional gate electrode that allows to control the carrier dynamics in the device and the degree of internal photoemission at the metal-semiconductor interfaces. We experimentally study the behavior of dedicated field-effect (FE-)PIPED test structures and develop a physical understanding of the underlying principles. We find that the THz down-conversion efficiency of FE-PIPED can be significantly increased when applying a gate potential. Building upon the improved understanding of the device physics, we further perform simulations and show that the gate field increases the carrier density in the conductive channel below the gate oxide to the extent that the device dynamics are determined by ultra-fast dielectric relaxation rather than by the carrier transit time. In this regime, the bandwidth can be increased to more than 1 THz. We believe that our experiments open a new path towards understanding the principles of internal photoemission in plasmonic structures, leading to PIPED-based optoelectronic signal processing systems with unprecedented bandwidth and efficiency.

Experimental Evidence of a Variant Neutron Spectrum from the T(t,2n)α Reaction at Center-of-Mass Energies in the Range of 16-50 keV.

Full calculations of six-nucleon reactions with a three-body final state have been elusive and a long-standing issue. We present neutron spectra from the T(t,2n)α (TT) reaction measured in inertial confinement fusion experiments at the OMEGA laser facility at ion temperatures from 4 to 18 keV, corresponding to center-of-mass energies (E_{c.m.}) from 16 to 50 keV. A clear difference in the shape of the TT-neutron spectrum is observed between the two E_{c.m.}, with the ^{5}He ground state resonant peak at 8.6 MeV being significantly stronger at the higher than at the lower energy. The data provide the first conclusive evidence of a variant TT-neutron spectrum in this E_{c.m.} range. In contrast to earlier available data, this indicates a reaction mechanism that must involve resonances and/or higher angular momenta than L=0. This finding provides an important experimental constraint on theoretical efforts that explore this and complementary six-nucleon systems, such as the solar ^{3}He(^{3}He,2p)α reaction.

Proton Spectra from

Few-body nuclear physics often relies upon phenomenological models, with new efforts at the ab initio theory reported recently; both need high-quality benchmark data, particularly at low center-of-mass energies. We use high-energy-density plasmas to measure the proton spectra from ^{3}He+T and ^{3}He+^{3}He fusion. The data disagree with R-matrix predictions constrained by neutron spectra from T+T fusion. We present a new analysis of the ^{3}He+^{3}He proton spectrum; these benchmarked spectral shapes should be used for interpreting low-resolution data, such as solar fusion cross-section measurements.

Using Inertial Fusion Implosions to Measure the T+

Light nuclei were created during big-bang nucleosynthesis (BBN). Standard BBN theory, using rates inferred from accelerator-beam data, cannot explain high levels of ^{6}Li in low-metallicity stars. Using high-energy-density plasmas we measure the T(^{3}He,γ)^{6}Li reaction rate, a candidate for anomalously high ^{6}Li production; we find that the rate is too low to explain the observations, and different than values used in common BBN models. This is the first data directly relevant to BBN, and also the first use of laboratory plasmas, at comparable conditions to astrophysical systems, to address a problem in nuclear astrophysics.

Measurement of the T + T neutron spectrum using the national ignition facility.

Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100

Measurements of the T(t,2n)4He neutron spectrum at low reactant energies from inertial confinement implosions.

Measurements of the neutron spectrum from the T(t,2n)4He (tt) reaction have been conducted using inertial confinement fusion implosions at the OMEGA laser facility. In these experiments, deuterium-tritium (DT) gas-filled capsules were imploded to study the tt reaction in thermonuclear plasmas at low reactant center-of-mass (c.m.) energies. In contrast to accelerator experiments at higher c.m. energies (above 100 keV), these results indicate a negligible n + 5He reaction channel at a c.m. energy of 23 keV.

Atypical severe Puumala hantavirus infection and virus sequence analysis of the patient and regional reservoir host.

Nephropathia epidemica (NE) caused by Puumala hantavirus (PUUV) is a mild variant of haemorrhagic fever with renal syndrome, which is endemic in Germany. We describe the case of a 67-year-old man initially presenting with acute bilateral angle-closure glaucoma, an atypical clinical presentation of PUUV infection. Subsequently, the patient developed a severe course of disease additionally complicated by profound hepatitis and interstitial nephritis, both phenomena which are rarely described in association with hantavirus infection. Serologic diagnosis was complicated by delayed antibody production until the 10th day of illness; however, PUUV RNA was detectable early in disease. To further analyse this unusual case, sequencing of the PUUV S segment was performed from the patient and regional reservoir host which showed a close relation.

[Ocular signs of a mitochondrial trifunctional protein defect. A long-term follow-up]. / Okuläre Zeichen eines mitochondrialen trifunktionalen Proteindefekts. Eine Langzeitbeobachtung.

A 13-year-old boy presented with a defect of the mitochondrial trifunctional protein (MTP). The MTP complex catalyses ß-oxidation of long chain fatty acids. Disorders of this multienzyme complex result in accumulation of hydroxylated long chain fatty acids which leads to chorioretinopathy. Ophthalmoscopic findings in these patients include fine hyperpigmentation while autofluorescence reveals hyperfluorescent granules at the posterior pole. Visual acuity, visual fields and electroretinography are within the normal range. A special long chain fatty acid-reduced diet seems to delay the progression of chorioretinopathy.

Evidence for stratification of deuterium-tritium fuel in inertial confinement fusion implosions.

Measurements of the D(d,p)T (dd) and T(t,2n)(4)He (tt) reaction yields have been compared with those of the D(t,n)(4)He (dt) reaction yield, using deuterium-tritium gas-filled inertial confinement fusion capsule implosions. In these experiments, carried out on the OMEGA laser, absolute spectral measurements of dd protons and tt neutrons were obtained. From these measurements, it was concluded that the dd yield is anomalously low and the tt yield is anomalously high relative to the dt yield, an observation that we conjecture to be caused by a stratification of the fuel in the implosion core. This effect may be present in ignition experiments planned on the National Ignition Facility.

[Accuracy of two autorefractors--Pediatric Autorefractor plusoptiX and Retinomax--in cycloplegic children in comparison to retinoscopy]. / Zur Messung der objektiven Refraktion in Zykloplegie im Kindesalter mit Skiaskopie und automatischer Refraktometrie mit dem Pediatric Autorefractor und dem Retinomax.

HISTORY: In children, measuring refraction is of interest particularly with regard to the risk of amblyopia. Cycloplegic retinoscopy is the gold standard method for this age group. In a prospective study we compared readings from two hand-held photorefractors, the Pediatric Autorefractor and the Retinomax, to those from retinoscopy. PATIENTS AND METHODS: 74 patients were recruited consecutively at the outpatient department of Heidelberg University Eye Hospital's Section for Strabismology and Neuroophthalmology. All patients underwent standardised cycloplegia measurements first by the Pediatric Autorefractor plusoptiX A 08 in 1 metre working distance, then adding an infrared filter to reduce interferences, followed by the Retinomax K-plus 3 in 5 cm working distance and retinoscopy as reference on the right eye. RESULTS: Spherical equivalents measured by the Pediatric Autorefractor plusoptiX A 08 coincided in 51.2% with retinoscopy (± 0.5 D). Adding an infrared filter increased this to 60.0%. However, the success rate of measurement decreased to 47% on adding an infrared filter as compared to 55.4% in cycloplegia alone. Children showed no cooperation in 11% and 16% with the infrared filter, respectively. The remaining children were not measurable by means of the device. With regard to spherical equivalents, the measurements done with Retinomax K-plus 3 coincide in 57% with those done in retinoscopy. The success rate of measurements with the Retinomax was 91%. The remaining children showed no cooperation. CONCLUSION: Retinoscopy in cycloplegia is still the method of choice when determining refraction in children. Autorefractors quickly provide results for comparison which coincide with retinoscopy in 50-60% in spherical equivalent and in 80-90% in cylindrical values. The Pediatric Autorefractor is not suited for everyday clinical routine due to a low success rate of 50% and tight measuring range of + 5.0 to -7.0 D in spherical equivalents.

Ionization of doped helium nanodroplets: complexes of C60 with water clusters.

Water clusters are known to undergo an autoprotonation reaction upon ionization by photons or electron impact, resulting in the formation of (H(2)O)(n)H(3)O(+). Ejection of OH cannot be quenched by near-threshold ionization; it is only partly quenched when clusters are complexed with inert gas atoms. Mass spectra recorded by electron ionization of water-doped helium droplets show that the helium matrix also fails to quench OH loss. The situation changes drastically when helium droplets are codoped with C(60). Charged C(60)-water complexes are predominantly unprotonated; C(60)(H(2)O)(4)(+) and (C(60))(2)(H(2)O)(4)(+) appear with enhanced abundance. Another intense ion series is due to C(60)(H(2)O)(n)OH(+); dehydrogenation is proposed to be initiated by charge transfer between the primary He(+) ion and C(60). The resulting electronically excited C(60)(+*) leads to the formation of a doubly charged C(60)-water complex either via emission of an Auger electron from C(60)(+*), or internal Penning ionization of the attached water complex, followed by charge separation within {C(60)(H(2)O)(n)}(2+). This mechanism would also explain previous observations of dehydrogenation reactions in doped helium droplets. Mass-analyzed ion kinetic energy scans reveal spontaneous (unimolecular) dissociation of C(60)(H(2)O)(n)(+). In addition to the loss of single water molecules, a prominent reaction channel yields bare C(60)(+) for sizes n=3, 4, or 6. Ab initio Hartree-Fock calculations for C(60)-water complexes reveal negligible charge transfer within neutral complexes. Cationic complexes are well described as water clusters weakly bound to C(60)(+). For n=3, 4, or 6, fissionlike desorption of the entire water complex from C(60)(H(2)O)(n)(+) energetically competes with the evaporation of a single water molecule.

Temperature effects on the dissociative electron attachment to dichlorobenzene isomers.

Dissociative electron attachment to all three isomers of dichlorobenzene has been investigated in the electron energy range from 0 to 2 eV and in the gas temperature range from 391 to 696 K using a crossed electron-molecular beam apparatus with a new temperature-regulated effusive molecular beam source. In the case of the dissociative electron attachment channel Cl(-)/1,2-dichlorobenzene and Cl(-)/1,4-dichlorobenzene, strong enhancement of the negative ion production with the gas temperature at low electron energies has been observed. The low-energy peak increases dramatically when the gas temperature is raised from 391 to 696 K. Activation energies for dissociative electron attachment of (482 +/- 20) meV for 1,2-dichlorobenzene and (59 +/- 20) meV for 1,4-dichlorobenzene have been determined. For the resonance at (0.49 +/- 0.03) eV in 1,2-dichlorobenzene and (0.32 +/- 0.03) eV in 1,4-dichlorobenzene, no dependence of the cross sections on the gas temperature has been observed. In the case of the dissociative electron attachment to Cl(-)/1,3-dichlorobenzene, the cross section does not depend on the temperature in the electron energy range from 0 to 2 eV. Quantum chemical calculations of the reaction energies and of the potential energy curves involved in the dissociation of Cl(-) have been performed, together with an analysis of the thermo dynamical accessibility of the relevant vibrational modes. Possible reasons for the different temperature dependences of the isomers are discussed.

[Pilot study of the Heidelberg diplopia questionnaire]. / Pilotstudie zu einem Heidelberger Doppelbildfragebogen.

PURPOSE: To test the visual-function-related quality of life in patients with diplopia, we designed a new questionnaire: the Heidelberg diplopia questionnaire. PATIENTS AND METHODS: In a prospective study, 51 patients with different ocular motility diseases (congenital and acquired) were asked about their everyday life impairment. The questionnaire encompasses the following subscales: duration of diplopia, spatial perception, motion in space, driving difficulties, difficulties at work, near vision, social function, and subjective complaints. RESULTS: The median composite questionnaire score correlated well with the patients' subjective complaints (Spearman's rho 0.70, p=0.000001) and their driving difficulties. There was a weak correlation with the clinical assessment of diplopia in the field of binocular vision based on the suggestions of Haase and Steinhorst and of Kolling. CONCLUSION: The Heidelberg diplopia questionnaire records patients' subjective complaints concerning diplopia. This study serves as the starting point for further studies in this field.

Decreased exercise blood pressure in older adults after exercise training: contributions of increased fitness and decreased fatness.

OBJECTIVE: To describe the contribution of changes in fitness and fatness resulting from exercise training on changes in submaximal exercise blood pressure (BP) during treadmill testing. DESIGN AND SETTING: Prospective, randomised, controlled trial. PARTICIPANTS: Sedentary older adults (n = 115) with untreated prehypertension or mild hypertension. INTERVENTION: Six-month supervised aerobic and strength training. MAIN OUTCOME MEASUREMENT: Systolic BP (SBP) was assessed at rest and during each stage of a maximal graded exercise test (GXT) that determined Vo(2)peak. General and regional fatness was assessed by anthropometry, dual-energy x-ray absorptiometry and MRI. BP changes were calculated for each GXT stage, and multivariate regression models were used to describe the association of changes in exercise BP with changes in fitness and fatness. RESULTS: After training, exercisers versus controls had significantly increased Vo(2)peak and significantly lower measures of general and regional fatness. Also, stage-specific SBP was significantly lower at stage 3 (-9.4 vs -1.6 mm Hg, p = 0.03) and stage 4 (-7.9 vs -1.2 mm Hg, p = 0.03). Pooled regression analysis across all stages showed that exercisers had a 7.1 mm Hg reduction in SBP, but this reduction fell short of statistical significance (p = 0.12) compared with controls. A 1.0 ml/kg/min increase in Vo(2)peak and a 1.0 cm decrease in waist circumference independently predicted a 1.0 mm Hg decrease in exercise SBP (p = 0.04 and p = 0.001, respectively). CONCLUSIONS: Decreased exercise SBP was independently associated with decreased waist circumference, a marker of abdominal obesity and increased fitness. These findings suggest that exercise training improves multiple factors that have an independent influence on SBP.

Pro-inflammatory interleukin-18 and Caspase-1 serum levels in liver failure are unaffected by MARS treatment.

BACKGROUND: The pro-inflammatory cytokine IL-18 and its activator Caspase-1 are involved in acute liver failure and acute-on-chronic-liver-failure. In acute liver failure and acute-on-chronic-liver-failure, the MARS system has been used to support liver function. Enhancement of IL-18, as seen in other extracorporeal-support systems like hemodialysis might thus have mitigated beneficial effects of the MARS system in acute hepatic failure. PATIENTS AND METHODS: We measured serum concentrations of IL-18 and Caspase-1 in 10 patients with acute liver failure and 10 patients suffering from acute-on-chronic-liver-failure, who were all treated with MARS. Thirteen patients suffering from chronic hepatic failure and 15 healthy individuals served as controls. Data are given as mean with 95% CI. RESULTS: Baseline IL-18 serum concentrations were significantly increased in acute liver failure and acute-on-chronic-liver-failure patients as compared to chronic hepatic failure (P=0.0039 and P=0.0011, respectively) and controls (P=0.0028 and P=0.0014, respectively). Caspase-1 serum concentrations were as well significantly elevated in the acute liver failure and acute-on-chronic-liver-failure groups as compared to chronic hepatic failure patients (P=0.0039 and P=0.0232, respectively) and controls P<0.0001 and P<0.0007, respectively). IL-18 and Caspase-1 did not change significantly during MARS treatment in acute liver failure and acute-on-chronic-liver-failure patients. CONCLUSIONS: MARS had no effect on IL-18 and Caspase-1 serum concentrations in acute liver failure and acute-on-chronic-liver-failure, providing no evidence of harmful effects by the increase of these potentially hepatocidal cytokines.

Formation of even-numbered hydrogen cluster cations in ultracold helium droplets.

Neutral hydrogen clusters are grown in ultracold helium nanodroplets by successive pickup of hydrogen molecules. Even-numbered hydrogen cluster cations are observed upon electron-impact ionization with and without attached helium atoms and in addition to the familiar odd-numbered H(n)(+). The helium matrix affects the fragmentation dynamics that usually lead to the formation of overwhelmingly odd-numbered H(n)(+). The use of high-resolution mass spectrometry allows the unambiguous identification of even-numbered H(n)(+) up to n approximately = 120 by their mass excess that distinguishes them from He(n)(+), mixed He(m)H(n)(+), and background ions. The large range in size of these hydrogen cluster ions is unprecedented, as is the accuracy of their definition. Apart from the previously observed magic number n=6, pronounced drops in the abundance of even-numbered cluster ions are seen at n=30 and 114, which suggest icosahedral shell closures at H(6)(+)(H(2))(12) and H(6)(+)(H(2))(54). Possible isomers of H(6)(+) are identified at the quadratic configuration interaction with inclusion of single and double excitations (QCISD)/aug-cc-pVTZ level of theory.

Hot topics in liver intensive care.

Liver dysfunction is an independent predictor of mortality among intensive care patients. Avoidance or early restoration of normal liver function should therefore be targeted in all critically ill patients. The present work seeks to provide an overview of the "hottest topics" among liver-related problems in intensive care. The management of increased intracranial pressure in severe hepatic encephalopathy is still not sufficiently documented. The promising results with regard to intracranial pressure control by the molecular adsorbent recycling system (MARS) in animal studies are only partially reproducible in patients. Intracranial pressure monitoring is inconsistently applied in various centers, mainly because of the lack of information about the risk benefit ratio. Further, we still do not know which coagulation management protocol reduces the risk of intracranial bleeding. Type I hepatorenal syndrome is a complication of liver failure that is strongly associated with bad outcomes. Only about the half of the patients will recover from dialysis-dependent hepatorenal syndrome after liver transplantation. The usefulness of combined liver and kidney transplantation has not been sufficiently clarified. Terlipressin together with fluid and albumin substitution appear to be the most promising therapeutic interventions. Extracorporeal liver support systems, such as single-pass albumin dialysis, MARS, and the dialysis- and plasmapheresis-based Prometheus, are still under investigation with regard to effectiveness of toxin elimination, appropriate indications, and number duration of treatments.

Fragmentation of metastable SF(6)(-*) ions with microsecond lifetimes in competition with autodetachment.

Fragmentation of metastable SF(6)(-*) ions formed in low energy electron attachment to SF(6) has been investigated. The dissociation reaction SF(6)(-*)-->SF(5) (-)+F has been observed approximately 1.5-3.4 micros and approximately 17-32 micros after electron attachment in a time-of-flight and a double focusing two sector field mass spectrometer, respectively. Metastable dissociation is observed with maximum intensity at approximately 0.3 eV between the SF(6)(-*) peak at zero and the SF(5)(-) peak at approximately 0.4 eV. The kinetic energy released in dissociation is low, with a most probable value of 18 meV. The lifetime of SF(6)(-*) decreases as the electron energy increases, but it is not possible to fit this decrease with statistical Rice-Ramsperger-Kassel/quasiequilibrium theory. Metastable dissociation of SF(6)(-*) appears to compete with autodetachment of the electron at all electron energies.

Reliability of three different visual acuity testing procedures in school children.

AIM: To evaluate the usability and reliability of three different visual acuity (VA) testing procedures using Landolt C's in 8 positions with a semi-automated computer program in school children. METHODS: 100 school children (median 7 years, 59 boys and 41 girls) were included; only the better eye was tested. We used the semi-automated computer program CORVIS.VT in a forced choice method. Three different test strategies were employed, each two times: A) DIN, B) Standard-Staircase and C) Best-PEST procedure with sequences A, B, C or A, C, B. RESULTS: Average testing time was 100 s +/- 45 (DIN), 59 s +/- 36 (Staircase) and 77 s +/- 25 (Best-PEST). The mean VA estimated with DIN was equivalent to that with the Best-PEST procedure. However, the mean VA with Standard-Staircase was one line less. In DIN, 76% of the retest scores were within 0.1 logMAR unit of the initial test score (Staircase: 72%, Best-PEST 73%). The 95% confidence interval of test-retest reliability was calculated to be -0.05 +/- 0.24 logMAR in DIN, +0.02 +/- 0.32 logMAR in Staircase, and 0.00 +/- 0.29 logMAR in Best-PEST. CONCLUSION: A high percentage of children aged 6 to 9 years (98%) can be tested with Landolt C's (8 positions). We found a decreasing test-retest reliability starting from DIN via Best-PEST to Staircase in this configuration.