513 research outputs found
The three-body recombination of a condensed Bose gas near a Feshbach resonance
In this paper, we study the three-body recombination rate of a homogeneous
dilute Bose gas with a Feshbach resonance at zero temperature. The ground state
and excitations of this system are obtained. The three-body recombination in
the ground state is due to the break-up of an atom pair in the quantum
depletion and the formation of a molecule by an atom from the broken pair and
an atom from the condensate. The rate of this process is in good agreement with
the experiment on Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.
A Cretaceous carbonate delta drift in the Montagna della Maiella, Italy
The Upper Cretaceous (Campanian\u2013Maastrichtian) bioclastic wedge of the Orfento Formation in the Montagna della Maiella, Italy, is compared to newly discovered contourite drifts in the Maldives. Like the drift deposits in the Maldives, the Orfento Formation fills a channel and builds a Miocene delta-shaped and mounded sedimentary body in the basin that is similar in size to the approximately 350 km 2 large coarse-grained bioclastic Miocene delta drifts in the Maldives. The composition of the bioclastic wedge of the Orfento Formation is also exclusively bioclastic debris sourced from the shallow-water areas and reworked clasts of the Orfento Formation itself. In the near mud-free succession, age-diagnostic fossils are sparse. The depositional textures vary from wackestone to float-rudstone and breccia/conglomerates, but rocks with grainstone and rudstone textures are the most common facies. In the channel, lensoid convex-upward breccias, cross-cutting channelized beds and thick grainstone lobes with abundant scours indicate alternating erosion and deposition from a high-energy current. In the basin, the mounded sedimentary body contains lobes with a divergent progradational geometry. The lobes are built by decametre thick composite megabeds consisting of sigmoidal clinoforms that typically have a channelized topset, a grainy foreset and a fine-grained bottomset with abundant irregular angular clasts. Up to 30 m thick channels filled with intraformational breccias and coarse grainstones pinch out downslope between the megabeds. In the distal portion of the wedge, stacked grainstone beds with foresets and reworked intraclasts document continuous sediment reworking and migration. The bioclastic wedge of the Orfento Formation has been variously interpreted as a succession of sea-level controlled slope deposits, a shoaling shoreface complex, or a carbonate tidal delta. Current-controlled delta drifts in the Maldives, however, offer a new interpretation because of their similarity in architecture and composition. These similarities include: (i) a feeder channel opening into the basin; (ii) an excavation moat at the exit of the channel; (iii) an overall mounded geometry with an apex that is in shallower water depth than the source channel; (iv) progradation of stacked lobes; (v) channels that pinch out in a basinward direction; and (vi) smaller channelized intervals that are arranged in a radial pattern. As a result, the Upper Cretaceous (Campanian\u2013Maastrichtian) bioclastic wedge of the Orfento Formation in the Montagna della Maiella, Italy, is here interpreted as a carbonate delta drift
Precision Measurement of the 29Si, 33S, and 36Cl Binding Energies
The binding energies of 29Si, 33S, and 36Cl have been measured with a
relative uncertainty using a flat-crystal spectrometer.
The unique features of these measurements are 1) nearly perfect crystals whose
lattice spacing is known in meters, 2) a highly precise angle scale that is
derived from first principles, and 3) a gamma-ray measurement facility that is
coupled to a high flux reactor with near-core source capability. The binding
energy is obtained by measuring all gamma-rays in a cascade scheme connecting
the capture and ground states. The measurements require the extension of
precision flat-crystal diffraction techniques to the 5 to 6 MeV energy region,
a significant precision measurement challenge. The binding energies determined
from these gamma-ray measurements are consistent with recent highly accurate
atomic mass measurements within a relative uncertainty of .
The gamma-ray measurement uncertainties are the dominant contributors to the
uncertainty of this consistency test. The measured gamma-ray energies are in
agreement with earlier precision gamma-ray measurements.Comment: 13 pages, 4 figure
Recyclable and Robust Optical Nanoprobes with Engineered Enzymes for Sustainable Serodiagnostics
Recyclable fluorescence assays that can be stored at room temperature would greatly benefit biomedical diagnostics by bringing sustainability and cost-efficiency, especially for point-of-care serodiagnostics in developing regions. Here, a general strategy is proposed to generate recyclable fluorescent probes by using engineered enzymes with enhanced thermo-/chemo-stability, which maintains an outstanding serodiagnostic performance (accuracy >95%) after 10 times of recycling as well as after storage at elevated temperatures (37 °C for 10 days). With these three outstanding properties, recyclable fluorescent probes can be designed to detect various biomarkers of clinical importance by using different enzymes
Multi‐Channel Lanthanide Nanocomposites for Customized Synergistic Treatment of Orthotopic Multi‐Tumor Cases
Simultaneous photothermal ablation of multiple tumors is limited by unpredictable photo-induced apoptosis, caused by individual intratumoral differences. Here, a multi-channel lanthanide nanocomposite was used to achieve tailored synergistic treatment of multiple subcutaneous orthotopic tumors under non-uniform whole-body infrared irradiation prescription. The nanocomposite reduces intratumoral glutathione by simultaneously activating the fluorescence and photothermal channels. The fluorescence provides individual information on different tumors, allowing customized prescriptions to be made. This enables optimal induction of hyperthermia and dosage of chemo drugs, to ensure treatment efficacy, while avoiding overtherapy. With an accessional therapeutic laser system, customized synergistic treatment of subcutaneous orthotopic cancer cases with multiple tumors is possible with both high efficacy and minimized side effects
Emissivity measurements at room temperature on polymeric and inorganic samples
Abstract An evaluation of the emissivity of polymeric and inorganic materials has been carried out in the spectral range 8-121J.m using a direct technique. For polymeric samples the study focused on the dependence on the doping level. In the case of the inorganic samples measurements were aimed at the evaluation of the emissivity variations with the temperature Furthermore the effects on the emissivity of temperature differences between the sample and the background on the emissivity evaluation have been studied
Customized Enhancement of Thermal Sensitivity of Tumors at Different Subcutaneous Depths by Multichannel Lanthanide Nanocomposites
The photothermal therapeutic effect on tumors located at different subcutaneous depths varies due to the attenuation of light by tissue. Here, based on the wavelength-dependent optical attenuation properties of tissues, the tumor depth is assessed using a multichannel lanthanide nanocomposite. A zeolitic imidazolate framework (ZIF-8)-coated nanocomposite is able to deliver high amounts of the hydrophilic heat shock protein 90 inhibitor epigallocatechin gallate through a hydrogen-bonding network formed by the encapsulated highly polarized polyoxometalate guest. It is superior to both bare and PEGylated ZIF-8 for drug delivery. With the assessment of tumor depth and accumulated amount of nanocomposite by fluorescence, an irradiation prescription can be customized to release sufficient HSP90 inhibitor and generate heat for sensitized photothermal treatment of tumors, which not only ensured therapeutic efficacy but also minimized damage to the surrounding tissues
Monitoraggio biologico ed esposizione a silice: applicazione di nuovi indicatori di dose e di effetto
In 16 addetti alla produzione di marmi
ricomposti è stato misurato Si-CAE, è stata eseguita
una spirometria e sono stati dosati 8oxoGua, 8oxoGuo,
8oxodGuo, SP-A, SP-D, CC16 e HO-1. Si sono osservati
valori spirometrici (FVC e FEV1) più bassi nei lavoratori
rispetto ai controlli. Nei lavoratori abbiamo osservato livelli
più elevati dei seguenti marcatori: Si-CAE, 8oxoGuo
ed espressione di HO-1. Lo studio evidenzia che l’esposizione
a silice può aumentare i livelli di Si-CAE, che può essere usato
per stimare la dose al bersaglio. Infine si evidenziavano
aspecifiche alterazioni spirometriche ed un aumento
di biomarcatori d’effetto
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