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1.
As feature sizes shrink, transient failures of on-chip network links become a critical problem. At the same time, many applications require guarantees on both message arrival probability and response time. We address the problem of transient link failures by means of temporally and spatially redundant transmission of messages, such that designer-imposed message arrival probabilities are guaranteed. Response time minimisation is achieved by a heuristic that statically assigns multiple copies of each message to network links, intelligently combining temporal and spatial redundancy. Concerns regarding energy consumption are addressed in two ways. First, we reduce the total amount of transmitted messages, and, second, we minimise the application response time such that the resulted time slack can be exploited for energy savings through voltage reduction. The advantages of the proposed approach are guaranteed message arrival probability and guaranteed worst case application response time.  相似文献   
2.
A novel type of polarization-independent optical isolator is described which utilizes the polarization walkoff provided by birefringent crystals. Isolation of 44 dB is measured at a wavelength of 1.3 mu m with single-mode fiber insertion loss of 1.5 dB. A temperature-independent scheme is also described that provides at least 39 dB of isolation over the temperature range of 25-75 degrees C.<>  相似文献   
3.
PMR1, a P-type ATPase cloned from the yeast Saccharomyces cerevisiae, was previously localized to the Golgi, and shown to be required for normal secretory processes (Antebi, A., and Fink, G.R. (1992) Mol. Biol. Cell 3, 633-654). We provide biochemical evidence that PMR1 is a Ca2+-transporting ATPase in the Golgi, a hitherto unusual location for a Ca2+ pump. As a starting point for structure-function analysis using a mutagenic approach, we used the strong and inducible heat shock promoter to direct high level expression of PMR1 from a multicopy plasmid. Yeast lysates were separated on sucrose density gradients, and fractions assayed for organellar markers. PMR1 is found in fractions containing the Golgi marker guanosine diphosphatase, and is associated with an ATP-dependent, protonophore-insensitive 45Ca2+ uptake activity. This activity is virtually abolished in the absence of the expression plasmid. Furthermore, replacement of the active site aspartate within the phosphorylation domain had the expected effect of abolishing Ca2+ transport activity entirely. Interestingly, the mutant enzymes (Asp-371 --> Glu and Asp-371 --> Asn) demonstrated proper targeting to the Golgi, unlike analogous mutations in the related yeast H+-ATPase. Detailed characterization of calcium transport by PMR1 showed that sensitivity to inhibitors (vanadate, thapsigargin, and cyclopiazonic acid) and affinity for substrates (MgATP and Ca2+) were different from the previously characterized sarco/endoplasmic reticulum and plasma membrane Ca2+-ATPases. PMR1 therefore represents a new and distinct P-type Ca2+-ATPase. Because close homologs of PMR1 have been cloned from rat and other organisms, we suggest that Ca2+-ATPases in the Golgi will form a discrete subgroup that are important for functioning of the secretory pathway.  相似文献   
4.
Conclusions We demonstrate that it is, in principle, possible to obtain refractory high-alumina cement on industrial equipment at the Semiluksk refractories factory. Technological parameters were developed for preparing raw mixtures, pressing the green articles and firing in a tunnel kiln. It was established that the mass percentage of SiO2 in the raw mixture should not exceed 1.5%. For industrial production of high-alumina cement in department No. 1 it is necessary to implement measures on the mechanization of the production process.Translated from Ogneupory, No. 5, pp. 26–28, May, 1986.  相似文献   
5.
Multithreaded servers with cache-coherent shared memory are the dominant type of machines used to run critical network services and database management systems. To achieve the high availability required for these tasks, it is necessary to incorporate mechanisms for error detection and recovery. Correct operation of the memory system is defined by the memory consistency model. Errors can therefore be detected by checking if the observed memory system behavior deviates from the specified consistency model. Based on recent work, we design a framework for dynamic verification of memory consistency (DVMC). The framework consists of mechanisms to verify three invariants that are proven to guarantee that a specified memory consistency model is obeyed. We describe an implementation of the framework for the SPARCv9 architecture, and we experimentally evaluate its performance using full-system simulation of commercial workloads.  相似文献   
6.
No Heading We present vibrating wire viscometer experiments in concentrated and dilute 3He-4He mixtures showing that the slip length may become orders of magnitude larger than the mean free path due to increased specular scattering of the 3He quasiparticles with the superfluid 4He film on the wire. The experimental results are in good agreement with a recent theory for slip which accounts for the cylindrical geometry of the wire and for velocity slip in directions normal as well as tangential to the surface of the wire.PACS numbers: 67.60.Fp, 51.20.+d  相似文献   
7.
The systemic inflammatory syndrome concept is one of the foundations that stand at the basis of revolutionary modern and future therapies, based on the in-depth understanding of the delicate mechanisms that govern the collaboration between the systems and organs of the human body and, at the same time, the fine balance that ensures a reproach-free operation. An interesting concept that we propose is that of the environment-inadequacy status, a concept that non-specifically incorporates all the situations of the organism’s response disorders in the face of imprecisely defined situations of the environment. The correlation between these two concepts will define the future of modern medicine, along with the gene-adjustment mechanisms. Psoriasis is a clear example of an inadequate body response as a result of exposure to as of yet undefined triggers with an excessive systemic inflammatory reaction and hitherto insufficiently controllable. Modern biological therapies, such as TNF-α, IL-12 family, and IL-17 inhibitors, are intended to profoundly reshape the cytokine configuration of patients with inflammatory diseases such as psoriasis, with tremendous success in disease control. Yet, because of the important roles of cytokines in cancer promotion and control, concern was raised about the fact that the use of biologicals may alter immune surveillance and promote cancer progression. Both theoretical and practical data nevertheless showed that the treatment-induced control of cytokines may be beneficial for reducing the inflammatory milieu that promotes cancer and such have a beneficial role in maintaining health. We briefly present the intricate roles of those cytokine families on cancer control, with some debates on if their inhibition might or might not promote additional tumoral development.  相似文献   
8.
Ultrasmall superparamagnetic iron oxide (Fe3O4) nanoparticles coated by biocompatible pullulan (Pu‐USPIO) with sizes below 10 nm and having a magnetite core and a hydrophilic outer shell of pullulan were prepared. The formed Pu‐USPIOs were thoroughly characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, atomic force microscopy, and small‐angle X‐ray scattering experiments. The content of magnetic nanoparticles embedded into the pullulan matrix was determined by thermogravimetric analysis. Vibrating sample magnetometry analysis was used to evaluate the magnetic properties of the Pu‐USPIO samples. Because of the presence of pullulan, these nanoparticles could be conditioned in many versatile forms, from a clear solution to magnetic films, for potential applications, including magnetic hyperthermia mediators. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42926.  相似文献   
9.
During the last decades, authorities’ awareness on environmental and human health impact at national and international level has increased in the field of small arms ammunition containing lead and antimony. Thus, the evolution of environmental policies regarding production and use of heavy metals and their compounds, especially in EU countries, implied extensive studies on the environmental implications of 9×19 mm caliber ammunition use, especially in indoor shooting ranges. In this context, the paper describes the experimental studies performed on Pb‐containing conventional FMJ (full metal jacketed) ammunition and comparative measurements on new ammunition designed for training. The combustion products and residues from conventional Pb‐containing ammunition and Cu‐based “greener” ammunition were compared in terms of gaseous products, metal concentration in aerosols and metal concentrations in solid residues. Gas emissions and solid residues were measured for four different types of ammunitions. The results showed that the copper content of the residue is significantly higher in case of Cu‐containing composite bullets. For the ammunition equipped with Pb bullet, an important percentage of the Pb residue is generated by erosion of the exposed part of the bullet core. On the other hand, the ammunition containing Cu‐composite bullet generates large quantities of Cu residues, which have similar environmental impact and less impact on human health. Gas analysis indicated the presence of CO and NOx and, surprisingly, high concentrations of HCN, CH4, and NH3. Lower gas concentrations are obtained for the composite bullets due to an incomplete combustion of gun propellant.  相似文献   
10.

Today, cities face many significant challenges, and the smart city concept is a promising means to address typical traditional city problems. The wireless e-health technologies is an evolving topic in the area of telemedicine nowadays. Mobile telecommunication and the use of multimedia technologies are the core of providing better access to healthcare personnel on the move. These technologies provide equal access to medical information and expert care leading to a better and a more efficient use of resources. Mobile and Fog computing technologies can also cope with many challenges in smart healthcare resources of mobility, scalability, efficiency, and reliability. Optimal healthcare systems are particularly critical in cities, due to the highly concentrated populations. This high population increases the potential for harm and damage in the case of negligence or improper treatment. This can lead to infections and disease outbreaks, which could become epidemic situations and require containment, which is very costly. Motivated by the need for better usage and management of healthcare resources, which is crucial for reliable healthcare delivery, this paper introduces a model that can provide improved delivery and utilization of resources. The quality reward-based model was developed to study and react to the satisfaction factors of healthcare systems, and proposes an optimization-based algorithm called the Maximum Reward Algorithm (MRA), that enhances the use and delivery of healthcare resources. The algorithm has been tested with multiple experiments and simulations, and has proved that it can provide reliability, efficiency and achieves 50.1% to 77.2% performance improvement.

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