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We report the first formal verification of a reintegration protocol for a safety-critical distributed embedded system. A reintegration protocol increases system survivability by allowing a transiently-faulty node to regain state. The protocol is verified in the Symbolic Analysis Laboratory (SAL), where bounded model-checking and decision procedures are used to verify infinite-state systems by k-induction. The protocol and its environment are modeled using a recently-developed explicit real-time model. Because k-induction has exponential complexity, we optimize this model to reduce the size of k necessary for the verification and to make $k$ invariant to the number of nodes. A corollary of the verification is that a clique avoidance property is satisfied.

To discuss the effect of the association of Shiquandabutang with Hetaokun on the protection to liver and immunity of tumor mouse S180.Through the comparison between tumor transplanted and tumor cultured completely out of cell body, the effect was investigated, with Hetaokun singly used and Shiquandabutang associated with Hetaokun, on the level of SGPT, licking up function of monocyte macrophage, thymus index, spleen index and transform percentage of lymphocyte of the mouse S180. The scanning electron micrographs indicated the protective function of the association of Shiquandabutang with Hetaokun for liver.12.5 mg x kg(-1) Hetaokun could obviously restrain the tumor when it was singly used at 73.1%, but it increased SGPT at the same time. The association of Shiquandabutang with Hetaokun could protect liver of the mouse S180. SGPT (P0.05) was compared with the common ones and the result showed that the association of shiquandabutang with Hetaokun could make K value increase (P0.01). Through the scanning electron micrographs, association of two medicines was found to change liver cells little and expansion of rough Neizhiwang was not found. Compared with the control group, the immunity of the two tumor mouse groups taking the medicine mentioned above was promoted obviously.The association of Shiquandabutang with Hetaokun can enhance the efficiency and decrease poison of them to body. With the promotion of immunity of the body, the efficiency is enhanced on the whole.

We studied the cell wall alterations that occur in mutants of Kluyveromyces lactis impaired in glycosylation. The mutants belong to four complementation groups named vga1 to vga4 (vanadate glycosylation affected), characterized by sodium orthovanadate resistance and alteration of the glycosylation profile of native invertase. A drastic reduction of the alkali-soluble fraction of the beta-D-glucan was observed in vga1, vga2 and vga3 cells, accompanied by an increase in the chitin content of the cell wall. In vga4 cells, both beta-D-glucan fractions (alkali-soluble and alkali-insoluble) were reduced to about half of the corresponding wild-type value but the chitin content was normal. A protein related to Fks1p, the catalytic subunit of the major 1,3-beta-D-glucan synthase of S. cerevisiae, was detected in K. lactis. The amount of this Fks1p-like protein increased 7-10 times in vga1, vga2 and vga3 mutants as compared to wild-type cells; the same strains released significant amounts of beta-D-glucan in the culture supernatant. These mutations also resulted in abnormally thick cell walls with conspicuous irregularities in the structure, as revealed by electron microscopy and by an altered resistance to Zymolyase. The observed high responsiveness of cell wall phenotypes to alterations of glycosylation make K. lactis an attractive system for studying the interconnections between these processes.

The binding of complement C3 to the cell surface of Klebsiella pneumoniae exposed to human serum complement after treatment with or without sub-MIC of antibiotics was examined by double diffusion immunoprecipitation against anti-human complement C3, and the production of oxygen-derived radicals by human polymorphonuclear leukocytes stimulated by complement-opsonized K. pneumoniae after treatment with or without sub-MIC of antibiotics was measured using the chemiluminescence (CL) assay. Complement C3 bound to the cell surface of K. pneumoniae treated with cefodizime was detected after exposure to human serum complement. The CL response induced by complement-opsonized bacteria after treatment with cefodizime was much higher than the response induced by nontreated bacteria or complement-opsonized bacteria after treatment with other antibiotics. These findings indicate that treatment with sub-MIC cefodizime make K. pneumoniae more susceptible to opsonization by complement and promotes the specific phagocytosis mediated by complement receptors.

ROMM is a class of Randomized, Oblivious, Multi-phase, Minimal routing algorithms. Our conjecture is that ROMM routing offers a potential for improved performance compared to fully randomized algorithms under both light and heavy loads. Our conjecture is also that ROMM routing offers close to best case performance for many common permutations. These conjectures are supported by extensive simulations of binary cube networks for a number of routing patterns. We show that k×n buffers per node suffice to make k-phase ROMM routing free from deadlock and livelock on n-dimensional binary cubes.

A parallel interface between a periodic multilayer structure and a uniform external medium can support surface electromagnetic waves. The energy in such a wave is localised about the boundary, and is excluded from the bulk of the multilayer structure by a Bragg condition. The possibility of quasi-single-mode behaviour, together with the freedom to make k as low as the plane-wave value in the external medium, and the great sensitivity of k to the detailed properties of the edge layer, gives these surface waves many potential applications in optical sensors, modulators, and other devices.

Premixed laminar flat flames of H 2 , O 2 and N 2 have been burnt, with trace amounts of various metals (Li, Na, K, Rb, Cs, Ga, In and Tl) and the halogens Cl, Br or I added. Mass spectrometric measurements were made of ion concentrations and also their variation with time in each flame. These observations establish that a halogen X can cause a metal A to produce ions homogeneously in a flame through the forward steps of A + X ^ A + + X - (II) AX + M A + + X - + M, (III) where M is any molecule. The reverse processes are found to facilitate ion recombination. We have measured the rate constants k 2 and k 3 of the ion-producing steps in (II) and (III) over the temperature range 1820—2590 K; they vary with temperature according to k 2 = A 2 exp ( - A EJRT) and k 3 = A 3 T -3-5 exp ( - AE 3 /RT). The activation energies of each reaction were found to equal the appropriate endothermicity, in contrast with previous shock tube determinations of k 3 . For Ga and In with all three halogens, ion recombination rates were measured directly with a little (lt; 1 vol. %) C 2 H 2 also added to the burner supplies. These observations unambiguously gave k -2 , the coefficient for recombination in (II), because k -3 is very small for these two metals. Also, it was found that these k -2 for Ga and In did not equal the ratio of the measured forward rate constant, k 2 , and the equilibrium constant for (II). The origin of this departure from detailed balancing is apparently that the ionizing step in (II) proceeds from A and X in their ground states, but the reverse recombination of ions is to ground state Ga, In or Tl and electronically excited ( 2 P1/2) atoms of X. This conclusion was confirmed by computations of k -2 using Landau-Zener curve-crossing theory for the products being either ground state atoms or with X excited. The alkali metals K, Rb and Cs, on the other hand, participate in each direction in (II) with A and X only in their ground states (so that detailed balancing does hold), except that there are one or two cases where excited states of A are important and result in anomalously large k 2 and k -2 . Li and Na are in an intermediate position, in that ionization in (II) proceeds only from ground state A and X, but both excited and ground state halogen atoms can be the products of ion recombination. Detailed balancing does not strictly hold with Li and Na in (II), but use of it is not likely to generate errors greater than a factor of 2. We were not able to detect any systematic or significant temperature dependence of k -2 for any A and X, and conclude that curve-crossing theory gives a good general account of how k -2 varies amongst the various A and X. Detailed balancing always appears to hold for reaction (III) and our values of the three-body ion recombination coefficient, k -3 , derived indirectly from k 3 and the equilibrium constant, indicate that it varies as T -3 . Also, its magnitude is almost three times larger than predicted by Bates and Flannery’s theory, except for a few A and X, where curve-crossing considerations make k -3 undetectably small.

This paper concerns, in the first instance, a sequence {t(1), t(2), t(3), …} of positive numbers denned successively bywhere k ∈ ℕ = {1,2,3,…} andThus, when k is odd, A(k) consists of those divisors of k that do not exceed k/3; when k is even, A (k) consists of those even divisors n of k that make k/n odd and do not exceed k/3. The sets A(k) are listed in Table 1 for k ≤ 105; the numbers t(1) to t(10) are 1, 1, 4/3, 1, 6/5, 4/3, 8/7, 1, 14/9, 6/5.

All known propagating rifts (PR's) are growing away from shallow ridge axis seafloor. We examine a model for rift propagation in which the ridge axis conduit, like a crack in the lithosphere, propagates in response to a stress concentration at its tip. The stress concentration near the tip which causes progressive failure of the lithosphere is primarily due to excess gravity-spreading stresses associated with anomalously shallow ridge axis along the growing ridge. This stress concentration near the tip is characterized by a stress intensity factor K, which must exceed a threshold value to cause failure of the plate. A remotely applied tensile stress would make a positive contribution to K but would act equally on both ridge segments and not favor the propagation of either. The pressure in the crack may, depending on its distribution, make either a positive or negative contribution to K. For a high enough propagation rate, viscous flow induced suction due to the growth of the ridge axis as well as the reduced vertical flow near the PR tip would make K < 0. This simple model thus includes a mechanism to control the speed of propagation and is consistent with the axial morphology of the spreading segment associated with the well-studied 95.5°W PR of the Galapagos spreading center. Analytical solutions for the contribution to the stress intensity factor of viscous forces resisting ridge axis growth and causing the PR axial topography are consistent with the observed propagation rate for asthenosphere viscosities of about 1019 Pa s (1020 P). We also examine a more general model of a ridge-transform-ridge system on the basis of energy conservation. In terms of energetics this more general model reduces to that of a single propagating ridge axis crack when both the work done by forces driving propagation and the viscous dissipation due to forces resisting propagation are generated along the growing ridge axis. However, the more general model also includes mechanisms that may stop ridge propagation. Propagation will stop either when the energy needed for transform migration is larger than that available for ridge axis growth or when the strain energy absorbed at the dying ridge axis is comparable to that released at the growing ridge axis, i.e., if the stress intensity factors for both ridge axes are similar. Both of these possibilities may occur when the propagating rift completely propagates through a ridge segment as at 85°W in the Galapagos. Finally, in this model the slight systematic differences in ridge axis orientation of the growing and dying ridges are a consequence rather than a cause of ridge propagation.

Suppose that we have enough computer time to make n observations of a stochastic process by means of simulation and would like to construct a confidence interval for the steady-state mean. We can make k independent runs of m observations each (n=k.m) or, alternatively, one run of n observations which we then divide into k batches of length m. These methods are known as replication and batch means, respectively. In this paper, using the probability of coverage and the half length of a confidence interval as criteria for comparison, we empirically show that batch means is superior to replication, but that neither method works well if n is too small. We also show that if m is chosen too small for replication, then the coverage may decrease dramatically as the total sample size n is increased.

Publisher Summary This chapter discusses photo cathodes on polycrystalline CsI/Na. It is difficult to make semitransparent photo cathodes on polycrystalline CsI/Na (hereafter denoted p-CsI/Na) having both high sensitivity and long life. When a photocathode is made on p-CsI/Na, the photocurrent, which is initially high, often decreases during operation. The two ways of producing the photocathode differ in the first process. The first step of one method is introduction of abundant alkali metal vapor to the p-CsI/Na. This process, called doping, is different from that used in forming conventional photo cathodes. To make K-Cs-Sb bi-alkali photo cathodes, potassium or other alkali metals are used for doping. The potassium is introduced in a heated dispenser at a constant substrate temperature and the system is evacuated. The composition of each oxide layer is variable according to which alkali metal is introduced and whether it is made of composite layers. It is then essential that, after deposition of alkali metal on the substrate is completed, oxygen can be introduced to oxidize the alkali metal.

Pancreatic adenocarcinoma is the fifth leading cause of cancer death in the United States. Mutations in the K-ras oncogene occur in 85% of pancreatic adenocarcinomas and have also been identified in 75% of pancreatic ducts with mucinous cell hyperplasia seen in association with chronic pancreatitis. We identified K-ras mutations in 65% of duct lesions associated not only with chronic pancreatitis but also with pancreatic adenocarcinoma and distal common bile duct carcinoma (cholangiocarcinoma). These observations make K-ras a potential candidate for a gene-based diagnostic test. Indeed, K-ras mutations have been demonstrated in the pancreatic secretions of patients with pancreatic carcinoma and pancreatic intraductal neoplasia. We analyzed stool specimens for mutated K-ras sequences using a plaque hybridization assay in patients with pancreatic adenocarcinoma, cholangiocarcinoma, and chronic pancreatitis. K-ras mutations were detected in stool specimens from 6 of 11 patients with pancreatic adenocarcinoma, from 2 of 3 patients with cholangiocarcinoma, and from 1 of 3 patients with chronic pancreatitis. The K-ras mutations found in stool specimens from patients with pancreatic carcinoma were identical to those in the primary cancer in five cases. Mutations found in the stool specimens from one patient with pancreatic cancer, one patient with chronic pancreatitis, and two patients with cholangiocarcinoma were the same as those identified in pancreatic ductal mucinous cell hyperplasia lesions present in the resected pancreas specimens. Our data suggest that the K-ras mutations originating from cells of pancreatic adenocarcinomas and from cells shed by abnormal pancreatic duct epithelium can be detected in the stool. These results support the further exploration of stool K-ras analysis as a potential screening assay for the early detection of pancreatic adenocarcinoma and precursor lesions such as pancreatic ductal mucinous cell hyperplasia.

(2) O(M)= t, +(8)(t)= 0 (s= 1 2,*** ,r1), then +(x) is said to define an iteration of order r to the root t. In fact, for r> 1, when xo is in a sufficiently small neighborhood of t the sequence (3) x+1 = 4(xi) converges to t with (4) = + O(xi O)r For analyticf, iterations of all orders exist and can be constructed in many ways. Domb [2]1 has shown further that for polynomial f it is always possible to make k a polynomial. The purpose of this note is to describe a simple algorithm: Let f(x) be a polynomial with no multiple factors; let p(x) and q(x) be any polynomials satisfying

The purposes of the present note are to point out some of the errors in a paper by F. J. W. Whipple1 and to discuss qualitatively the space-charge near the Earth's surface. This latter problem has been solved more exactly by W. F. G. Swann,2 E. R. von Schweidler,3 and others and the discussion to follow adds nothing essentially new to their results but is perhaps of interest because the main results are obtained by extremely simple considerations. As Whipple says, the current at the surface of the Earth is carried entirely by positive ions. This is because the negative ions are removed by the field and none comes from the Earth to replace them. Thus a positive space-charge exists at the surface of the Earth; and this conclusion holds irrespective of whether there is any diffusion or not. In fact if i is the air-earth current, F is the field strength (normally positive), and w is the mobility of the positive ions, the space-charge will be +(i/Fw); also dF/dx = +(4πi/Fw). These conclusions depend on the assumptions that all the current at the ground is carried by positive ions, that at x = 0 there is no space-charge except that of the positive ions, that Poisson's equation holds, and that a steady state has been reached. Now Whipple's equations [either (9) or (11)] indicate that the space-charge at the surface depends on his diffusion constant k, in fact, if k = 0 they lead to an infinite value for the space-charge. The cause of this trouble is that Whipple's equation (2) is incorrect as is seen if we make k approach zero when it leads toi = (λ1+λ2) F which, as Wrhipple states, is incorrect at the Earth's surface. Thus Whipple's statement, “The accumulation of positive electricity near the ground on account of the interplay of conduction and diffusion is known as the electrode-effect,” is entirely misleading. There is a positive space-charge at the ground because the field carries the negative ions away and the conclusion is independent of whether there is or is not diffusion.