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1.
The goal of scaled permuted string matching is to find all occurrences of a pattern in a text, in all possible scales and permutations. Given a text of length n and a pattern of length m we present an O(n) algorithm.  相似文献   
2.
A mass-spectrometric method was used to investigate the kinetics of the vaporization of potassium bromide single crystals. In electron-impact-ionization mass spectra of molecular fluxes vaporized from a free-surface of KBr, ions of K+, KBr+, Br+, and K2Br+ originating from KBr and K2Br2 molecular precursors were detected in the temperature range 724–918 K. The temperature dependencies of ion currents, ln IiT – 1/ T, of the most abundant ions (K+, KBr+, and K2Br+) revealed a departure from the linearity. From a comparison between the equilibrium and nonequilibrium vaporization rates, it was concluded that the value of the vaporization coefficient for monomers and dimers passes through a maximum at about 800 and 825 K, respectively. An electron-impact-fragmentation pattern of KBr molecules, I(K+)/I(KBr+), was observed to pass reproducibly through a minimum at the temperatures of about 800 to 830 K. In the fluxes from a free surface and from one inside a Knudsen cell, the dimer-to-monomer ratios were found to vary with temperature in different ways. The difference in the equilibrium and nonequilibrium rates of vaporization, the temperature dependence of the fragmentation pattern, and the mechanism of association reactions are discussed in light of the terrace-ledge-kink and surface-charge models.  相似文献   
3.
This paper presents data and criteria to assess and guide the design of modems for coded noncoherent communication systems subject to practical system constraints of powerS, bandwidthW, noise spectral density N0, coherence time Tc, and number of orthogonal signalsM. Three basic receiver types are analyzed for the noncoherent multifrequency-shift keying (MFSK) additive white Gaussian noise channel: hard decision, unquantized (optimum), and quantized (soft decision). Channel capacity and computational cutoff rate Rcompare computed for each type and presented as functions of the predetection signal-to-noise ratioST/N_{0}and the number of orthogonal signalsM = 2TW. This relates the channel constraints of power, bandwidth, coherence time, and noise power to the optimum choice of signal durationT leq T_{c}and signal numberM.  相似文献   
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5.
Patients with advanced heart failure often remain severely symptomatic and have a high mortality rate despite currently available therapy. We studied the safety and efficacy of a new approach to the patient with refractory heart failure: continuous intravenous treatment via a portable infusion pump with epoprostenol (prostacyclin), a potent pulmonary and systemic vasodilator. A group of 33 patients with severe heart failure (64% New York Heart Association class IV and 36% class III) and profound ventricular dysfunction (median left ventricular ejection fraction, 0.15)--despite prior treatment with diuretics (100%), digitalis (91%), angiotensin-converting enzyme inhibitors (85%), and dobutamine (30%)--underwent a baseline 6-minute walk test prior to dose titration with epoprostenol during invasive hemodynamic monitoring. Subjects responding during the dose titration were randomized, on an open basis, to receive either continuous epoprostenol infusion via an indwelling central venous catheter plus conventional therapy or conventional therapy alone for 12 weeks. The initial dose-ranging study with epoprostenol produced a significant decline in systemic and pulmonary vascular resistance and a substantial increase in cardiac index despite a fall in pulmonary capillary wedge pressure. Symptoms related to vasodilation were noted within the first week after randomization to epoprostenol in 9 of 16 patients but resolved with adjustment of the infusion and concomitant medications in all but one subject. Dose adjustments during the chronic epoprostenol infusion were infrequent after the first week and complications related to the drug delivery system were rare. The change in distance walked from baseline to the last available 6-minute walk test was significantly greater in patients who received epoprostenol compared with patients assigned to standard therapy (72 +/- 40 vs -39 +/- 32 m, mean +/- SEM; p = 0.033). Our study suggests that long-term intravenous infusion of epoprostenol is feasible in patients with severe heart failure and our hemodynamic and functional results suggest clinical benefit as well. However, until recent results indicating an adverse effect of epoprostenol on survival are fully evaluated, the role of this drug in the treatment of advanced heart failure will remain uncertain.  相似文献   
6.
User-friendly software for the analysis of brain lesions (ABLe)   总被引:1,自引:0,他引:1  
We previously developed a software package called ABLe (analysis of brain lesions) which characterizes brain lesions in terms of lesion volume and intersection with cytoarchitecture (e.g. Brodmann areas). Since our previous publication, there have been significant improvements to this software package which utilize methods standard to the neuroimaging community. These features include spatial normalization to the MNI template brain (standard of the international consortium for brain mapping), and use of the volume occupancy Talairach labels (VOTL) and automated anatomical labeling (AAL) atlases for full brain quantification of structures impacted by the lesion. Methods for multi-subject studies including lesion-symptom mapping proposed by Bates et al. have been extended in ABLe to produce an exploratory analysis summarizing correlations between subjects with overlapping lesions and behavioral deficit. A subset of data from an ongoing traumatic head injury study correlating deficit with brain anatomy is used to demonstrate the power of this software package.  相似文献   
7.
Hemodialysis patients with soft tissue calcifications present unique challenges to nephrologists who play an integral role in their long‐term management. Although disorders of soft tissue calcification are rare in the general population, calciphylaxis and tumoral calcinosis are encountered in up to 4% of the end‐stage renal disease population. Although they are both associated with the deposition of calcium in the soft tissue, they are distinct entities that differ markedly in respect to their clinical presentation, morbidity, and mortality. It is therefore exceedingly important that the nephrologist be aware of these disorders, be able to recognize them, and be able to differentiate them from each other to diagnose and treat patients appropriately. To achieve this it is necessary that the nephrologist be familiar with the diagnostic tools and the treatment modalities that are available. A case of a patient with soft tissue calcifications is presented followed by an overview of these disorders including a comparison of the clinical, laboratory, radiologic, and histologic findings, as well as treatment.  相似文献   
8.
Leader-group interaction was studied to determine the effect of leaders with varying degrees of directiveness. Group activity was observed with individuals high and low in "control," as established by a questionnaire. The results indicate that when a leader exerts effective (frequent but low magnitude of) control, the group moves towards more successful resolutions of problems; that when leaders are low in skillful control, group members begin to vie with one another for leadership. From Psyc Abstracts 36:02:2CF60S. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
In a low-noise environment, a simple inversion circuit can be used for quick-look decoding of a convolutional code. The bit error performance of the raw inversion circuit is improved by a simple pattern-recognition technique operating on the syndrome stream, which is also used to acquire node sync.  相似文献   
10.
A mass spectrometric method was used to study the kinetics of lithium fluoride single-crystal sublimation. In electron impact ionization mass spectra, Li+, LiF+, Li2F+, and Li3 F 2 + ions originating from monomer (LiF), dimer (Li2F2), and trimer (Li3F3) molecular precursors were detected in the temperature range 970–1070 K. The dimer-to-monomer and trimer-to-monomer flux ratios were found to increase progressively with increasing temperature and also in comparison with those measured under equilibrium of crystalline LiF with its saturated vapor. The temperature dependence of the ion current ratio I(Li2F+)/I(Li+) measured over the interval 916–1087 K was shown to pass reproducibly through a minimum at about 975 K. The enhancement of the rate of association reactions at LiF crystal surfaces is discussed in light of the terrace-ledge-kink model of vaporization and surface charge concept.  相似文献   
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