Circuit Electromechanics with a Non-Metallized Nanobeam

We have realized a nano-electromechanical hybrid system consisting of a silicon nitride beam dielectrically coupled to a superconducting microwave resonator. We characterize the sample by making use of the Duffing nonlinearity of the strongly driven beam. In particular, we calibrate the amplitude spectrum of the mechanical motion and determine the electromechanical vacuum coupling. A high quality factor of 480,000 at a resonance frequency of 14 MHz is achieved at 0.5 K. The experimentally determined electromechanical vacuum coupling of 11.5 mHz is quantitatively compared with finite element based model calculations.Comment: Typos and one reference have been correcte

Pregnancy-associated plasma protein-A is an independent short-time predictor of mortality in patients on maintenance haemodialysis

Aims Mortality of maintenance haemodialysis (HD) patients is very high due to polymorbidity, mostly from metabolic and cardiovascular disease. In order to identify patients with high risk for life-threatening complications, reliable prognostic markers would be helpful. Pregnancy-associated plasma protein-A (PAPP-A) has been shown to predict cardiovascular events and death in patients with stable coronary artery disease as well as in acute coronary syndrome in patients with normal renal function. It was the aim of this study to evaluate PAPP-A as a marker for death in patients on maintenance HD. Methods and results PAPP-A serum levels were measured in 170 patients participating in the monitor! trial, a prospective dynamic dialysis cohort multicenter study in Switzerland. Patients were followed up for a median time of 17 months after measuring PAPP-A, and evaluated for death of any cause. Survivors and non-survivors were compared with regard to baseline PAPP-A concentrations. A multivariate logistic regression analysis for death was performed including PAPP-A, age, sex, number of comorbidities, dialysis vintage, Kt/V, IL-6, C-reactive protein, parathyroid hormone (PTH), Ca × PO4 product, and total serum cholesterol. A cut-off value for PAPP-A was calculated for discrimination between patients with low and high mortality risk, respectively. A total of 23 deaths occurred during follow-up, equalling an incidence rate of 0.1. Baseline median PAPP-A levels were 40% higher in non-survivors vs. survivors (P = 0.023). In a multivariate analysis, only PAPP-A, age, and Ca × PO4 product were independent predictors of mortality. A cut-off value of 24 mIU/L discriminates significantly (P = 0.015) between patients at low or high risk for death with a negative predictive value of 91%. Conclusion PAPP-A is a novel and independent short-time predictor of mortality in a maintenance HD population. The pathogenetic relevance of PAPP-A, particularly in the development of cardiovascular disease, remains to be further elucidate

Successful treatment of hypercalcemia with cinacalcet in renal transplant recipients with persistent hyperparathyroidism

Background. Cinacalcet lowers plasma parathyroid hormone (PTH) levels in primary and secondary hyperparathyroidism. The efficacy and safety of cinacalcet have not been examined in renal transplant patients with persistent hyperparathyroidism. The aim of this study was to evaluate the effect of cinacalcet as a novel therapy for the management of such patients. Methods. Eleven renal allograft recipients with persistent hyperparathyroidism were treated with cinacalcet. The total study time was 10 weeks. Individual cinacalcet doses were adjusted to obtain a serum calcium in the predefined normal target range of 2.10-2.60 mmol/l. Results. Serum calcium decreased significantly from 2.73±0.05 mmol/l to 2.44±0.05 and 2.42± 0.04 mmol/l after 2 and 10 weeks of treatment, respectively. All patients reached the target range rapidly and remained normocalcaemic throughout the study. Serum PTH significantly decreased 16.1 and 21.8% at study weeks 2 and 10, respectively, compared with week 0. Serum phosphate increased. Renal function remained stable and no allograft rejection was observed. From weeks 2 to 10, daily cinacalcet doses administered were 30 mg (n = 8), 15 mg (n = 1) and 60 mg (n = 1), respectively. Conclusion. Cinacalcet was effective in correcting the hypercalcaemia associated with persistent hyperparathyroidism after renal transplantation. It appears to be safe. Thus, cinacalcet represents a promising alternative for parathyroidectomy in these patient

Magnon mode selective spin transport in compensated ferrimagnets

We investigate the generation of magnonic thermal spin currents and their mode selective spin transport across interfaces in insulating, compensated ferrimagnet/normal metal bilayer systems. The spin Seebeck effect signal exhibits a non-monotonic temperature dependence with two sign changes of the detected voltage signals. Using different ferrimagnetic garnets, we demonstrate the universality of the observed complex temperature dependence of the spin Seebeck effect. To understand its origin, we systematically vary the interface between the ferrimagnetic garnet and the metallic layer, and by using different metal layers we establish that interface effects play a dominating role. They do not only modify the magnitude of the spin Seebeck effect signal but in particular also alter its temperature dependence. By varying the temperature, we can select the dominating magnon mode and we analyze our results to reveal the mode selective interface transmission probabilities for different magnon modes and interfaces. The comparison of selected systems reveals semi-quantitative details of the interfacial coupling depending on the materials involved, supported by the obtained field dependence of the signal

Local charge and spin currents in magnetothermal landscapes

A scannable laser beam is used to generate local thermal gradients in metallic (Co2FeAl) or insulating (Y3Fe5O12) ferromagnetic thin films. We study the resulting local charge and spin currents that arise due to the anomalous Nernst effect (ANE) and the spin Seebeck effect (SSE), respectively. In the local ANE experiments, we detect the voltage in the Co2FeAl thin film plane as a function of the laser spot position and external magnetic field magnitude and orientation. The local SSE effect is detected in a similar fashion by exploiting the inverse spin Hall effect in a Pt layer deposited on top of the Y3Fe5O12. Our findings establish local thermal spin and charge current generation as well as spin caloritronic domain imaging

Temporal spying and concealing process in fibre-optic data transmission systems through polarization bypass

International audienceRecent research has been focused on the ability to manipulate a light beam in such a way to hide, namely to cloak, an event over a finite time or localization in space. The main idea is to create a hole or a gap in the spatial or time domain so as to allow for an object or data to be kept hidden for a while and then to be restored. By enlarging the field of applications of this concept to telecommunications, researchers have recently reported the possibility to hide transmitted data in an optical fibre. Here we report the first experimental demonstration of perpetual temporal spying and blinding process of optical data in fibre-optic transmission line based on polarization bypass. We successfully characterize the performance of our system by alternatively copying and then concealing 100% of a 10-Gbit s-1 transmitted signal.

Sirolimus ameliorates the enhanced expression of metalloproteinases in a rat model of autosomal dominant polycystic kidney disease

Background. Remodelling of matrix and tubular basement membranes (TBM) is a characteristic of polycystic kidney disease. We hypothesized that matrix and TBM degradation by metalloproteinases (MMPs) could promote cyst formation. We therefore investigated the renal expression of MMPs in the Han:SPRD rat model of autosomal dominant polycystic kidney disease (ADPKD) and examined the effect of sirolimus treatment on MMPs. Methods. 5-week-old male heterozygous (Cy/+) and wild-type normal (+/+) rats were treated with sirolimus (2 mg/kg/day) through drinking water for 3 months. Results. The mRNA and protein levels of MMP-2 and MMP-14 were markedly increased in the kidneys of heterozygous Cy/+ animals compared to wild-type +/+ as shown by RT-PCR and Western blot analyses for MMP-2 and MMP-14, and by zymography for MMP-2. Strong MMP-2 expression was detected by immunoperoxidase staining in cystic epithelial cells that also displayed an altered, thickened TBM. Tissue inhibitor of metalloproteinases-2 (TIMP-2) expression was not changed in Cy/+ kidneys. Sirolimus treatment leads to decreased protein expression of MMP-2 and MMP-14 in Cy/+, whereas MMP-2 and MMP-14 mRNA levels and TIMP-2 protein levels were not affected by sirolimus. Conclusion. In summary, in kidneys of the Han:SPRD rat model of ADPKD, there is a marked upregulation of MMP-2 and MMP-14. Sirolimus treatment was associated with a marked improvement of MMP-2 and MMP-14 overexpression, and this correlated also with less matrix and TBM alterations and milder cystic diseas

Environmental Exposure to Estrogenic and other Myco- and Phytotoxins

Zearalenone (ZON) is known as a very potent, naturally occurring estrogenic mycotoxin. It is one of the most prevalent mycotoxin produced as a secondary metabolite by Fusarium species growing on cereals such as wheat and corn. It has been studied extensively in food and feed products for decades but only rarely and somewhat by chance in the environment. We therefore elucidated its agro-environmental fate and behavior by conducting a series of field studies and monitoring campaigns. Specifically, ZON was investigated in plants, soils and drainage waters from wheat and corn fields artificially infected with Fusarium graminearum. In addition, manure, sewage sludge and surface waters were analyzed for ZON. Three main input pathways of ZON onto soil could be identified: i) wash-off from Fusarium-infected plants (in the order of 100 mg/ha), ii) plant debris remaining on the soil after harvest (up to few g/ha), and iii) manure application (in the order of 100 mg/ha). Our results show that these input sources altogether caused the presence of several g/ha of ZON in topsoil. Compared to this, ZON emission by drainage water from Fusarium-infected fields was generally low, with maximum concentrations of 35 ng/l and total amounts of a few mg/ha. Due to dilution, ZON concentrations dropped below environmental relevance in larger surface water bodies. However in small catchments dominated by runoff from agricultural land, ZON might substantially contribute to the estrogenicity of such waters. Apart from ZON, other natural toxins monitored in this study, such as the mycotoxin deoxynivalenol or the estrogenic phytoestrogen formononetin, emitted to and occurred in surface waters at considerably higher amounts. To date their ecotoxicological effects are largely unknown