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51.
In this paper we investigate the performance of a combined estimation/equalization technique for the mobile radio channel, assuming a GSM-recommended transmission format (narrowband TDMA with midamble, recommendation 5.04) and MSK modulation scheme. Channel estimation is performed via correlation of the received signal with a suitably modulated replica of the transmitted midamble. Equalization is then obtained by means of a maximum likelihood sequence estimation (MLSE) scheme in the form of a so-called Viterbi equalizer. Our analysis provides theoretical results concerning the bit error rate (BER) attained by the receiver for a given stationary multipath channel model. Simulation results are also presented in order to integrate and validate the theory.  相似文献   
52.
Cabergoline (CAB), a long-lasting dopamine-agonist, specific for the D2 receptor, is effective in normalizing serum PRL levels in most patients with microprolactinoma or idiopathic hyperprolactinemia. Because few data are presently available on the effects of CAB treatment in macroprolactinomas, the aim of this open-label study was to investigate whether this drug was effective in producing tumor shrinkage, as well as in normalizing PRL levels. Twenty-three patients with macroprolactinoma entered this study 15 patients had had no treatment, whereas the remaining 8 patients had been previously treated with bromocriptine, which was with-drawn because of intolerance. Three of 23 patients had undergone unsuccessful surgery. Pretreatment serum PRL levels ranged from 100-3860 micrograms/L. CAB was administered at a dose of 0.5-3 mg once or twice a week for 12-24 months. Magnetic resonance imaging (MRI) scans were performed before and 3, 6, 12, and 24 months after the beginning of treatment, to evaluate tumor shrinkage, defined as a decrease of at least 80% of baseline tumor volume. After 3-6 months of treatment with a low dose (0.5-1 mg/week), serum PRL levels normalized in 18 patients. In the remaining 5 patients, whose serum PRL levels were not normalized, the dose was increased to 2-3 mg/week. This schedule caused the normalization of PRL levels in 1 patient, whereas in the remaining 4 patients, PRL levels were reduced to 30-82 micrograms/L. A tumor volume reduction greater than 80% at MRI occurred in 14 of 23 patients (61%) after CAB treatment (from 2609.4 +/- 534.7 to 530.1 +/- 141.3 mm3 at the 12-24th month follow-up, P < 0.001). A volume reduction of 41.8 +/- 3.4% was already evident after 3 months (1436 +/- 285.9 mm3; P < 0.001). The complete disappearance of the tumor mass at MRI occurred after 6 months of treatment with CAB in 1 patient, and in 5 patients after 1 yr of treatment. An improvement of visual field defects was obtained in 9 of the 10 patients presenting visual impairment before CAB treatment. The drug was tolerated well by all patients. Only 1 patient experienced mild nausea, which disappeared spontaneously after the 2nd day of treatment. Long-term, a low dose of the D2 receptor agonist CAB significantly reduced tumor volume and normalized serum PRL levels in a great majority of patients bearing macroprolactinoma. This treatment met with excellent patient compliance. This study suggests that CAB can be used as a first choice drug treatment in macroprolactinomas, as already shown for microprolactinomas and idiopathic hyperprolactinemia.  相似文献   
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G. Ghelardoni  G. Lombardi 《Calcolo》1974,11(4):483-507
Sommario In questa nota vengono studiate proprietà delle soluzioni non banaliw(x) (0≤x≤1) del problema non linearew″+λw=g(w) w′ 2,w(0)=w(1)=0, dove λ è reale eg(w) è intera; sono studiati in dettaglio alcuni casi corrispondenti a scelte particolari dig.
Properties are obtained of the non trrivial solutionsw (x) (0≤x≤1) of the non linear boundary problemw″+λw=g(w)w′ 2,w(0)=w(1)=0, where λ is real andg(w) is entire. Some special cases (corresponding to special choices ofg) are studied in detail.
  相似文献   
55.
We report here the synthesis and preliminary pharmacological characterization of a novel Neurokinin A receptor antagonist. This molecule contains a dehydroalanine residue. It displays a high conformational rigidity and possesses very high activity. Its pharmacological properties as a neurokinin A receptor antagonist were assessed in in vitro experiments on rat vas deferens and were compared to those of Neuronorm and MEN10627.  相似文献   
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In this paper the application of software implemented voting (ring structures) to pipeline networks is presented. The TMR characterization of the ring is extended to various topologies such as trees, cascade and locally voted pipelines. Both the aspects of reliability and data flow are analyzed in detail.  相似文献   
59.
In the present work, 67 strains of Lactobacillus helveticus isolated from whey starter cultures and cheeses were identified and grouped by genotypic and phenotypic methods. Strains were identified by sugar fermentation pattern, by cell-wall protein profile, and by probe hybridisation. Phenotypic diversity was evaluated by a chemometric model taking into account biochemical characteristics (i.e. acidifying and peptidase activities) of technological interest. Genotypic diversity was evidenced by RAPD-PCR, which provided stran-specific patterns and revealed the occurrence of different strains. The RAPD-PCR profiles were clustered according to their similarities: the groups obtained, together with the cell-wall protein profiling and the chemometric information, could be sometimes correlated with the type of cheese and/or dairy niches used as sources of strains. A computerised analysis of genotypic and phenotypic information could be successfully applied for rapid and reliable differentiation and characterisation of Lb. helveticus isolates occurring in different dairy products.  相似文献   
60.
Quantifying economic and environmental benefits of co-located firms   总被引:1,自引:0,他引:1  
Resource sharing among co-located firms--referenced in the industrial ecology literature as "industrial symbiosis"--engages traditionally separate industries in a collective approach to business and environmental management involving the physical exchanges of materials, energy, water, and byproducts. While industrial symbiosis is seen hypothetically as a win-win situation, there are few analyses of the economic and environmental consequences for the individual participants in multi-faceted exchanges. In this article, the nascent industrial symbiosis network in Guayama, Puerto Rico, is explored from environmental, economic, and regulatory perspectives of the individual participants and the community. A coal-fired power plant, owned and operated by the AES Corporation, draws five million gallons per day of process water from nearby sources thus avoiding freshwater withdrawals and, through steam sales, significantly reduces emissions from a nearby refinery. This article quantifies economic and environmental costs and benefits for the symbiosis participants, concluding that there are substantial benefits to engaging in symbiosis, although these benefits fall unevenly on participating organizations. Policy intervention can be a viable means of motivating more regular occurrences of resource exchanges among groups of firms.  相似文献   
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