Search results for "trap"
showing 10 items of 2144 documents
Una inaspettata biodiversità valutata con la trappola malaise: il caso dei collemboli di Lampedusa
2013
All‟interno di uno studio sulla biodiversità dell‟entomofauna dell‟Isola di Lampedusa, che verteva principalmente sulla fauna aerea, si sono trovati diversi taxa normalmente appartenenti alla fauna edafica. Infatti per il monitoraggio sono state utilizzate trappole di tipo Malaise internazionalmente impiegate e consigliate nei protocolli per il monitoraggio di popolazioni di insetti volatori. Inaspettatamente, anche se qualche altro caso è citato in letteratura, si sono rinvenuti diversi taxa più tipicamente rappresentativi della fauna del suolo ed in particolare dell‟epifauna quali chilopodi, collemboli, coleotteri carabidi. La nostra attenzione si è focalizzata sui collemboli in quanto so…
Multicollision-induced dissociation of multiply charged gold clusters, Aun2+, n = 7–35, and Aun3+, n = 19–35
2000
Abstract Multicollision-induced dissociation (MCID) has been applied to gold clusters, Au n 2+ (n = 7–35) and Au n 3+ (n = 19–35) stored in a Penning trap. By application of ion cyclotron resonance excitation and pulses of argon collision gas, fragmentation yields have been measured as a function of the clusters’ kinetic energy. The corresponding dissociation energies have been determined by use of the impulsive collision theory and the quantum Rice–Ramsperger–Kassel (RRK) model for the energy transfer to internal cluster modes and for delayed dissociation, respectively. As compared to earlier measurements of singly charged gold clusters the variation of the stability as a function of clust…
Efficient gene delivery to the inflamed colon by local administration of recombinant adenoviruses with normal or modified fibre structure
1999
BACKGROUND/AIMSReplication deficient recombinant adenoviruses represent an efficient means of transferring genes in vivo into a wide variety of dividing and quiescent cells from many different organs. Although the gastrointestinal tract is a potentially attractive target for gene therapy approaches, only a few studies on the use of viral gene transfer vehicles in the gut have been reported. The prospects of using recombinant adenoviruses for gene delivery into epithelial and subepithelial cells of the normal and inflamed colon are here analysed.METHODSAn E1/E3 deleted recombinant adenovirus (denoted AdCMVβGal) and an adenovirus with modified fibre structure (denoted AdZ.F(pk7)) both express…
Scalable Creation of Long-Lived Multipartite Entanglement.
2017
We demonstrate the deterministic generation of multipartite entanglement based on scalable methods. Four qubits are encoded in Ca+40, stored in a microstructured segmented Paul trap. These qubits are sequentially entangled by laser-driven pairwise gate operations. Between these, the qubit register is dynamically reconfigured via ion shuttling operations, where ion crystals are separated and merged, and ions are moved in and out of a fixed laser interaction zone. A sequence consisting of three pairwise entangling gates yields a four-ion Greenberger-Horne-Zeilinger state |ψ=(1/2)(|0000+|1111), and full quantum state tomography reveals a state fidelity of 94.4(3)%. We analyze the decoherence o…
An Optimization Device for Series Parallel Connected PV Plants
2017
In this paper it is presented a testing prototype of a reconfiguration system for photovoltaic (PV) plants. The system enables to increase the total energy output by reducing the electrical mismatch between the PV array modules. The architecture of the implemented switching matrix, performing the dynamic electrical interconnections of the PV panels, enables to reconfigure nine solar modules in a series-parallel (SP) configuration. The contribution is organized as follows. A brief state of the art is first presented, followed by a comparison between the SP and Total-Cross-Tied (TCT) connections. The prototype then is thoroughly described as well as the main design choices. Finally some tests…
3D contour based local manual correction of tumor segmentations in CT scans
2009
Segmentation is an essential task in medical image analysis. For example measuring tumor growth in consecutive CT scans based on the volume of the tumor requires a good segmentation. Since manual segmentation takes too much time in clinical routine automatic segmentation algorithms are typically used. However there are always cases where an automatic segmentation fails to provide an acceptable segmentation for example due to low contrast, noise or structures of the same density lying close to the lesion. These erroneous segmentation masks need to be manually corrected. We present a novel method for fast three-dimensional local manual correction of segmentation masks. The user needs to draw …
Mass Spectrometry in Food Quality and Safety
2015
Abstract In recent years, mass spectrometry has gained a wide recognition as a selective and fast technique for the analysis and assessment of a wide range of food products. The state of the art in the determination of safety and quality of food is presented to illustrate the capability of this technique for classification and grading, defect and disease detection, distribution and visualization of chemical attributes, and evaluations of overall quality of meat, fish, fruits, vegetables, and other food products. The features of mass spectrometry for each category were summarized in the aspects of the investigated quality and safety attributes, the used systems (triple quadrupole, quadrupole…
Bleaching of optical activity induced by UV Laser exposure in natural silica
2004
We report experimental data on two types of natural silica, differing for their OH content, irradiated with UV photons (4.66 eV) from a pulsed Nd:YAG laser. Irradiation induces a reduction of the absorption band at 5.12eV and of the associated emissions at 3.14eV and 4.28eV, ascribed to twofold coordinated Ge (=Ge'') centers pre-existing in our samples. The bleaching is mainly due to the post-irradiation conversion of =Ge'' into the paramagnetic H(II) center via trapping of a H atom. Comparison with literature data points out the peculiarities of silica with a low Ge concentration as regards UV induced transformations.
Investigation of Space-Charge Phenomena in Gas-Filled Penning Traps
2009
The centering of ions in Penning traps by a quadrupolar radiofrequency excitation in the presence of a buffer gas has been studied in the regime of high charge‐densities. It is found to deviate significantly from the single‐particle situation. In particular, the efficiency of the cooling process is affected as well as the resolving power. The behavior has been studied experimentally at the preparation trap REXTRAP and the high‐precision Penning trap setup ISOLTRAP both located at the on‐line mass separator ISOLDE at CERN. In addition, the phenomenon has been investigated numerically by a custom‐designed simulation.
The trapping condition and a new instability of the ion motion in the ion cyclotron resonance trap
1995
Abstract In analogy to the critical mass, m crit , a critical voltage, U crit , (and a general trapping parameter, π trap ) is defined, above which the ion motion in an ion cyclotron resonance (ICR) trap is unstable and the ions are lost from the trap. The theoretical values for the critical voltage are confirmed by experimental results. Singly charged gold cluster ions, Au n − , of several sizes, n = 50, 60, 76, 100, 110, and 145 (the latter corresponding to an ion mass of 28 560 u), were injected into an ICR trap, stored, and detected by axial ejection and single ion counting using a microchannel plate detector. During the storage period the trapping voltage, U , was varied for extended d…