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1.
An algorithm for reconstructing the characteristics (charge, mass, and energy) of cosmic-radiation nuclei with 20- to 200-MeV/nucleon energies is described. The detector is a telescope of three two-coordinate planes with two 1-mm-thick iron filters inserted between them. Each plane is composed of two strip silicon detectors with 3.6-mm-wide orthogonally oriented strips, an effective area of 6 × 6 cm2, and a thickness of 380 m. The algorithm for reconstructing the nuclei characteristics is based on the analysis of how the specific ionization losses change as the nuclei pass through the filter material. The results of the Monte Carlo simulation are presented for the energy dependence of the telescope acceptance and the energy deposited in the detectors by different nuclei in view of the detector calibration on the nuclear beams of the accelerator. The mass resolution of the telescope is 30, 12, and 5% for He, N, and Al nuclei, respectively. The energy resolution, which is 20%, is much the same for all nuclei.  相似文献   
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The stability and functionality of GCC-bOBP, a monomeric triple mutant of bovine odorant binding protein, was investigated, in the presence of denaturant and in acidic pH conditions, by both protein and 1-aminoanthracene ligand fluorescence measurements, and compared to that of both bovine and porcine wild type homologues. Complete reversibility of unfolding was observed, though refolding was characterized by hysteresis. Molecular dynamics simulations, performed to detect possible structural changes of the monomeric scaffold related to the presence of the ligand, pointed out the stability of the β-barrel lipocalin scaffold.  相似文献   
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A novel linear silicon drift detector (SDD) is proposed in which the proper potential profile is established by the voltage drop along a unique p+ cathode implanted across the surfaces. This p+ implant, arranged in a zigzag shape, acts at the same time as voltage divider and field cathode and allows us to increase the sensitive area, improving also the uniformity of the thermal distribution and thus minimizing the fluctuation of the electron mobility on the sensitive zone of the SDD. The perturbations of the drift field due to the asymmetry of the strips constituting the zigzag cathode have been evaluated by solving analytically Poisson's equation for a simplified model of the structure. Three-dimensional numerical simulations have been carried out to prove the negligible amount of the perturbation and the effectiveness of the proposed structure. Based on this principle, a prototype has been manufactured at Canberra Semiconductor Company. Dynamic measurements of the time-of-flight of an injected charge prove that the linearity of the prototype and the drift uniformity in the anode direction are very high  相似文献   
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Being able to promptly and accurately choose a proper course of action in the field is a crucial aspect of emergency response. For this reason, emergency medical services (EMS) rely on well established procedures that apply to the most frequent cases first responders encounter in their practice, but do not include special cases concerning (sensory, motor or cognitive) disabled persons. In these cases, first responders may end up applying suboptimal or possibly wrong procedures or lose precious time trying to adapt on-the-fly to the special case. This paper proposes both (i) a detailed patient model for EMS that can account for peculiar aspects of the many existing disabilities and (ii) an adaptive information system called PRESYDIUM (Personalized Emergency System for Disabled Humans) that provides tailored instructions in the field for helping medical first responders in dealing with disabled persons. More precisely, we will illustrate and discuss: (i) the design and development process of PRESYDIUM, (ii) the patient model, which is partly based on the ICF (International Classification of Functioning, Disability and Health) standard proposed by the World Health Organization, (iii) the knowledge base used by the system to provide tailored instructions to medical first responders, (iv) the Web-based architecture of the system, (v) the different interfaces??including one for mobile devices??the system provides to enable all the identified stakeholders (disabled persons, their families, clinicians, EMS call center operators, medical first responders) to easily access and possibly provide data to the system, (vi) the evaluation of the validity of the patient model and of the system usability which has been conducted with end users.  相似文献   
6.
The utility of single-chain Fv proteins as therapeutic agentswould be realized if the circulating lives of these minimalantigen-binding polypeptides could be both prolonged and adjustable.We have developed a general strategy for creating tailored monoPEGylatedsingle-chain antibodies. Free cysteine residues were engineeredin an anti-TNF-  相似文献   
7.
The microstructure of ethylene (E)-norbornene (N) copolymers obtained by C s-symmetric i-Pr[(Cp)(9-Flu)]ZrCl2 (1) and C 1-symmetric i-Pr[(3-R-Cp)(9-Flu)]ZrCl2 (R = Me (2); R = i-Pr (3)) was determined by 13C NMR at tetrad (1) and pentad level (2, 3), respectively. This has allowed to study the influence of Cp substitutions on the statistical model of copolymerizations: Markov 1 statistics for 1 and 2; Markov 2 for 3, where the penultimate unit influences next insertion owing to steric interactions between i-Pr and copolymer chain. The presence of only racemic ENNE sequences in E–N copolymers by 1 shows that copolymerizations occur through chain migratory mechanism. Chain backskips account for the formation of both meso and rac NEN sequences with 1 and for the insertion of N and E at the same site of 2 and 3.  相似文献   
8.
Fruit leathers are made by drying a very thin layer of fruit puree to obtain a chewy product. The objective of this work was to minimise the drying time required to produce mango leathers with no preservatives and no sugar added, and to evaluate their acceptance and storage stability. Mango puree was spread on Petri dishes and oven‐dried according to a central composite design with two independent variables: drying temperature (60–80 °C) and puree load (0.4–0.6 g cm?2). The minimum drying time (120 min) resulted from drying a puree load of 0.5 g cm?2 at 80 °C. The product was well accepted, especially in terms of flavour. The mango leathers were packed in polypropylene buckets and stored at 25 °C. The combination between low water activity (0.62) and low pH (3.8) allowed the product to be microbiologically stable for at least 6 months, without the need for chemical preservatives.  相似文献   
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One of the most intriguing aspects of male reproductive physiology is the ability to generate spermatogenic cells - which are 'foreign' to the host - without triggering immune activation. After leaving the testis, spermatozoa enter the epididymis where they mature and are stored. In this study, we report a previously unrecognized dense network of dendritic cells (DCs) located at the base of the epididymal epithelium. This network was detected in transgenic mice expressing CD11c-EYFP and CX3CR1-GFP reporters. Epididymal DCs (eDCs) establish intimate interactions with the epithelium and project long dendrites between epithelial cells toward the lumen. We show that isolated eDCs express numerous leukocyte markers described previously in other organs that are in contact with the external environment, and present and cross-present ovalbumin to T cells in vitro. eDCs are, therefore, strategically positioned to regulate the complex interplay between immune tolerance and activation, a balance that is fundamental to male fertility.  相似文献   
10.
A silicon-tungsten calorimeter has been developed to be flown in the WiZard/CAPRICE balloon borne experiment to measure the flux of antiprotons, positrons and light nuclei in the cosmic radiation. The calorimeter is composed of 8 x, y silicon sampling planes [active area (48 × 48) cm2] interleaved with 7 tungsten absorbers (7 radiation lengths); it provides the topology of the interacting events together with an independent measurement of the deposited energy. Details of the front-end electronics and of the read-out system are given and the overall performances during pre-flight ground operations are described as well.  相似文献   
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