2,169 research outputs found
Deployment verification of large CFRP helical high-gain antenna for AIS signals
Deployment verification of large CFRP helical high-gain antenna for AIS signal
Experimental characterization of an uniaxial angle cut whispering gallery mode resonator
The usual configuration of uniaxial whispering gallery mode resonators is a
disk shaped geometry where the optic axis points along the symmetry axis, a so
called z-cut resonator. Recently x-cut resonators, where the optic axis lies in
the equatorial plane, became of interest as they enable extremely broadband
second harmonic generation. In this paper we report on the properties of a more
generalized system, the so called angle-cut resonator, where the optic axis
exhibits an arbitrary angle against the symmetry axis. We show experimentally
that the modal structure and quality factors are similar to common resonators
but that the polarization properties differ quite significantly: due to the
asymmetry the polarization depends on the equatorial position and is, in
general, elliptical
Author Correction: The third dimension in river restoration: how anthropogenic disturbance changes boundary conditions for ecological mitigation
Stable Large-scale CO2 Storage in Defiance of an Energy System Based on Renewable Energy â Modelling the Impact of Varying CO2 Injection Rates on Reservoir Behavior
AbstractThe IPCC Report 2014 strengthens the need for CO2 storage as part of climate change mitigation options. The further expansion of electricity generation by solar and wind and its preferential usage in Germany is leading to strong fluctuations in the CO2 output from former base load coal fired power plants. This study takes a look at the feasibility of large scale industrial CO2 injection into a saline aquifer structure with the main focus on varying injection rates. By means of simulation the influence of the most important parameters is analyzed
Vibronic origin of long-lived coherence in an artificial molecular light harvester
Natural and artificial light harvesting processes have recently gained new
interest. Signatures of long lasting coherence in spectroscopic signals of
biological systems have been repeatedly observed, albeit their origin is a
matter of ongoing debate, as it is unclear how the loss of coherence due to
interaction with the noisy environments in such systems is averted. Here we
report experimental and theoretical verification of coherent
exciton-vibrational (vibronic) coupling as the origin of long-lasting coherence
in an artificial light harvester, a molecular J-aggregate. In this
macroscopically aligned tubular system, polarization controlled 2D spectroscopy
delivers an uncongested and specific optical response as an ideal foundation
for an in-depth theoretical description. We derive analytical expressions that
show under which general conditions vibronic coupling leads to prolonged
excited-state coherence
Quality of life in peritoneal carcinomatosis: A prospective study in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC)
BACKGROUND/AIMS Cytoreductive surgery and hyperthermic intraperitoneal chemoperfusion (HIPEC) can improve survival in selected patients with peritoneal carcinomatosis, but bear a significant risk of perioperative morbidity. The aim of this study was to prospectively evaluate the quality of life (QoL) following cytoreduction and HIPEC.
METHODS In this study including 40 patients (65% females) with different primary tumors, the EORTC QLQ-C30 questionnaire was applied prior to CS and HIPEC as well as 3, 9, and 18 months postoperatively.
RESULTS Global health status was not impaired significantly following HIPEC. Scales and symptom scores that deteriorated 3 months postoperatively (p < 0.05), that is, physical, role, and social functions as well as fatigue, pain, dyspnea, insomnia, and diarrhea, all returned to preoperative values within 9 months.
CONCLUSIONS Following cytoreductive surgery and HIPEC, QoL returns to preoperative levels within 9 months. Selected patients that are likely to benefit oncologically from HIPEC should not be denied this option for fear of reduced postoperative QoL
Myocardial perfusion and regression of coronary artery disease in patients on a regimen of intensive physical exercise and low fat diet
AbstractThis intervention program tested the applicability and effects of intensive physical exercise and a low fat diet on progression of coronary atherosclerotic lesions and stress-induced myocardial ischemia in patients with stable angina pectoris. Eighteen patients participated in this program for 1 year; they consumed a low fat, low cholesterol diet (< 20 energy % fat, cholesterol < 200 mg/day) and exercised for >3 h/week. Change in coronary morphology was assessed by angiography and digital image processing; stress-induced myocardial ischemia was measured by thallium-201 scintigraphy. Results were compared with those in patients receiving âusual care.âIn the intervention group, significant regression of coronary atherosclerotic lesions was noted in 7 of the 18 patients: no change or progression was present in 11 patients. In patients receiving usual care, regression was detected in only 1, with no change or progression in 11 patients (different from intervention, p < 0.05). There was a significant reduction in stress-induced myocardial ischemia, which was not limited to patients with regression of coronary atherosclerotic lesions. Thus, regular physical exercise and a low fat diet may retard progression of coronary artery disease; however, improvement of myocardial perfusion may be achieved independently from regression of stenotic lesions
Increased CSF aquaporin-4, and interleukin-6 levels in dogs with idiopathic communicating internal hydrocephalus and a decrease after ventriculo-peritoneal shunting
Background: Studies in animal models, in which internal hydrocephalus has been induced by obstructing the cerebrospinal fluid pathways, have documented an up-regulation of the concentrations of aquaporin-4 (AQP4) in the brain. In this study, the concentrations of aquaporin-1 (AQP1), AQP1, AQP4 and interleukin-6 (IL-6) were determined in the CSF of dogs with idiopathic communicating hydrocephalus before and after the reduction of intraventricular volume following ventriculo-peritoneal shunt (VP-shunt) treatment. Results: The concentrations of AQP4 and IL-6 were increased in the cerebrospinal fluid of dogs with hydrocephalus compared to controls. Both parameters significantly decreased after surgical treatment, accompanied by decrease of ventricular size and the clinical recovery of the dogs. AQP1 was not detectable in CSF. Conclusions: Brain AQP4 up-regulation might be a compensatory response in dogs with hydrocephalus. Future determination of AQP4 at the mRNA and protein level in brain tissue is warranted to substantiate this hypothesis
Combining conductive atomic force microscopy with electrically detected magnetic resonance
We present the design and implementation of a scanning probe microscope, which
combines electrically detected magnetic resonance (EDMR) and
(photo-)conductive atomic force microscopy ((p)cAFM). The integration of a
3-loop 2-gap X-band microwave resonator into an AFM allows the use of
conductive AFM tips as a movable contact for EDMR experiments. The optical
readout of the AFM cantilever is based on an infrared laser to avoid
disturbances of current measurements by absorption of straylight of the
detection laser. Using amorphous silicon thin film samples with varying defect
densities, the capability to detect a spatial EDMR contrast is demonstrated.
Resonant current changes as low as 20 fA can be detected, allowing the method
to realize a spin sensitivity of 8Ă106spins/âHz at room temperature
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