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101.
D Rund S Ben-Neriah O Yehuda R Leizerowitz E Okon A Polliack 《Canadian Metallurgical Quarterly》1997,25(5-6):585-591
Hyperploidy is a rare finding in leukemias, with isolated cases of tetraploidy reported in acute myeloblastic and acute lymphblastic leukemias. We report the first case of acute myeloid leukemia with near-pentaploidy (5 n+/-) which was present in 100% of metaphases at diagnosis. By light microscopy, the leukemic blasts were exceptionally large and coarsely granulated. Following one cycle of induction chemotherapy, complete morphologic and cytogenetic remission was documented. Four weeks later relapse occured, at which time the karyotype was diploid and the morphological and immunophenotypic characteristics were those of a lymphoid leukemia. However, the presence of three aberrant chromosomes (5q+, 6q+ and 20q+) confirmed that this was clonal evolution of the original myeloid leukemia. To the best of our knowledge, this case represents the first report of near-pentaloidy in de novo, pretreatment human leukemia. 相似文献
102.
Yehuda Partom 《International Journal of Impact Engineering》1997,20(6-10):617-625
According to the quasi-steady-state approximation of long rod penetration, the total penetration efficiency should approach the so called hydrodynamic limit at high impact velocities. However, both experiments and computer simulations show that this is not the case. The total penetration efficiency usually overshoots the hydrodynamic limit at velocities above approximately 3 km/s. We ran computer simulations to investigate the significance of the hydrodynamic limit. We found that the overshoot occurs during the end (or terminal) phase. The end phase starts upon completion of the rod erosion. The kinetic energy trapped in the residual rod and in the target at this stage can cause significant additional deepening of the crater. As the overshoot of the hydrodynamic limit is an edge effect, it is expected to decrease as the aspect ratio of the rod increases. 相似文献
103.
This article reviews memory-related impairments in trauma survivors with posttraumatic stress disorder and their possible association to neuroendocrine alterations seen in this disorder. The neuroendocrine profile in PTSD first described in chronically ill combat veterans is characterized by lower basal cortisol levels, higher glucocorticoid receptor number, enhanced sensitivity to exogenous steroids, and increased variation in basal cortisol levels over the diurnal cycle. The generalizability and time course of these neuroendocrine alterations are explored in longitudinal studies and studies in other traumatized populations. These studies suggest that at least some aspects of this neuroendocrine profile can also be seen in other populations, including women, children, and victims of childhood trauma. Additionally, the alterations may be present early in the course of illness, perhaps even in the immediate aftermath of trauma, and may continue to be manifest in elderly trauma survivors. The mechanisms by which these neuroendocrine alterations may influence the formation and processing of traumatic memories are discussed. 相似文献
104.
Approximations for multiproduct contracts with stochastic demands and business volume discounts: single supplier case 总被引:1,自引:0,他引:1
In this paper we analyze contracts for multiple products when the supplier offers business volume discounts. The contract takes the form of price discounts for total minimum dollar volume commitments over the horizon with flexibility to adjust the total purchases upwards by a fixed percentage about this minimum commitment. The optimal policy could be complex since it involves the solution of a constrained multi-period multi-product dynamic program. We suggest approximations that give us an upper bound. To develop this upper bound, we present the optimal policy for a similar contract for a single product problem. We then develop a lower bound for the multiproduct problem and show, numerically, that the gap is small. Given the approximations standard single period resource allocation algorithms can be used to solve the problem. The resulting solution methodology is fast and permits evaluation of various what-if scenarios. 相似文献
105.
Yehuda Lindell 《Journal of Cryptology》2013,26(4):638-654
In this note, we show the existence of constant-round computational zero-knowledge proofs of knowledge for all $\mathcal {NP}$ . The existence of constant-round zero-knowledge proofs was proven by Goldreich and Kahan (Journal of Cryptology, 1996), and the existence of constant-round zero-knowledge arguments of knowledge was proven by Feige and Shamir (CRYPTO, 1989). However, the existence of constant-round zero-knowledge proofs of knowledge for all $\mathcal {NP}$ is folklore, to the best of our knowledge, since no proof of this fact has been published. 相似文献
106.
In the setting of secure computation, a set of parties wish to securely compute some function of their inputs, in the presence
of an adversary. The adversary in question may be static (meaning that it controls a predetermined subset of the parties) or adaptive (meaning that it can choose to corrupt parties during the protocol execution and based on what it sees). In this paper, we
study two fundamental questions relating to the basic zero-knowledge and oblivious transfer protocol problems:
• |
Adaptive zero-knowledge proofs: We ask whether it is possible to construct adaptive zero-knowledge proofs (with unconditional soundness) for all of NP\mathcal{NP}. Beaver (STOC [1996]) showed that known zero-knowledge proofs are not adaptively secure, and in addition showed how to construct zero-knowledge
arguments (with computational soundness). 相似文献
107.
Universal composability and concurrent general composition consider a setting where secure protocols are run concurrently with each other and with arbitrary other possibly insecure protocols. Protocols that meet the definition of universal composability are guaranteed to remain secure even when run in this strongly adversarial setting. In the case of an honest majority, or where there is a trusted setup phase of some kind (like a common reference string or the key-registration public-key infrastructure of Barak et al.?in FOCS 2004), it has been shown that any functionality can be securely computed in a universally composable way. On the negative side, it has also been shown that in the plain model where there is no trusted setup at all, there are large classes of functionalities which cannot be securely computed in a universally composable way without an honest majority. In this paper, we extend these impossibility results for universal composability. We study a number of public-key models and show for which models the impossibility results of universal composability hold and for which they do not. We also consider a setting where the inputs to the protocols running in the network are fixed before any execution begins. The majority of our results are negative and we show that the known impossibility results for universal composability in the case of no honest majority extend to many other settings. 相似文献
108.
Neta Zilony‐Hanin Michal Rosenberg Michal Richman Ronen Yehuda Hadas Schori Menachem Motiei Shai Rahimipour Alexander Groisman Ester Segal Orit Shefi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(45)
Nerve growth factor (NGF) plays a vital role in reducing the loss of cholinergic neurons in Alzheimer's disease (AD). However, its delivery to the brain remains a challenge. Herein, NGF is loaded into degradable oxidized porous silicon (PSiO2) carriers, which are designed to carry and continuously release the protein over a 1 month period. The released NGF exhibits a substantial neuroprotective effect in differentiated rat pheochromocytoma PC12 cells against amyloid‐beta (Aβ)‐induced cytotoxicity, which is associated with Alzheimer's disease. Next, two potential localized administration routes of the porous carriers into murine brain are investigated: implantation of PSiO2 chips above the dura mater, and biolistic bombardment of PSiO2 microparticles through an opening in the skull using a pneumatic gene gun. The PSiO2‐implanted mice are monitored for a period of 8 weeks and no inflammation or adverse effects are observed. Subsequently, a successful biolistic delivery of these highly porous microparticles into a live‐mouse brain is demonstrated for the first time. The bombarded microparticles are observed to penetrate the brain and reach a depth of 150 µm. These results pave the way for using degradable PSiO2 carriers as potential localized delivery systems for NGF to the brain. 相似文献
109.
A computational model of flashover is presented that closely follows the experimental setup at CNRS-ENSMA-Poitiers. A propane burner with thermal power of 55 kW is used as a primary source of fire and square beech wood samples (30 mm×30 mm×5 mm) as fire spread targets. The computational model describes the wood pyrolysis with a progress variable. Using the conservation of heat fluxes at the solid–gas interface, the thermal diffusion in the wood samples is coupled with the convective and the radiative heat transfer in the ambient gas phase. The incoming heat flux at the upper surface of the wood samples reaches values between 20 and 30 kW/m2. With the ignition and subsequent combustion of the pyrolysis volatiles, the heat flux increases by approx. 12 kW/m2. The results show that the ignition of the wood samples is triggered at an approx. surface temperature of 650 K. Due to large local variations in incident heat flux, significant differences in the ignition times of the wood samples are observed. The comparison of the calculated and the experimentally measured temperature shows a good agreement for the first wood sample and the model predicts the ignition time very well. But for the second and the third wood samples the model overpredicts the temperature, which leads to a premature ignition of these wood samples. 相似文献
110.
The effect of axial diffusion, usually neglected in mass transfer calculations, in investigated for the absorption process into a liquid film. The absorption takes place within a finite length of the film and the surface resistance is assumed to be constant. For such a system, several upstream and down-stream boundary conditions are analysed and the results are presented in terms of the overall Sherwood number.It is found that the effect of axial diffusion is appreciable for very short absorbing lengths or relatively low flow velocities. For long absorbing lengths, all cases considered are insensitive to the upstream and downstream boundary conditions. 相似文献
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