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Carstensen and Rhodes1 have suggested that when, in stability programs, assays cannot be performed immediately after the protocol-designated storage time, then freezing them until such a time when assays can be performed would be a reasonable manner to retain the protocol schedule. They caution, however, that such a procedure may not be valid for dissolution data. The article to follow deals with real-time data showing that such a process is feasible for Nalidixic Acid tablets (and presumably for other tablets as well), and that, furthermore, the dissolution pattern would seem to be “frozen” as well.  相似文献   
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This paper describes a fully integrated digital-spread spectrum transceiver chip fabricated through MOSIS in 1.2 μm CMOS. It includes a baseband spread spectrum transmitter and a coherent intermediate frequency (IF) receiver consisting of a Costas loop, an acquisition loop for the pseudo-noise (PN) sequence, and a clock recovery loop with a 406.4 MHz onchip numerically controlled oscillator (NCO). The transceiver is capable of operating at a maximum IF sampling rate of 50.8 MS/s and a maximum chip rate of 12.7 R Mchips/s (Mcps) with selectable data rates of 100, 200, 400, and 800 kbps. At the maximum operating speed of 50.8 R MS/s, it dissipates 1.1 W. In an additive white Gaussian noise channel the IF receiver achieves a receiver output SNR within 1 dB of theory and can acquire code with a wide range of input SNR from -17 dB to over 30 dB. The transceiver chip has been interfaced to an RF up/down converter to demonstrate a wireless voice/data/video link operating in the 902-928 MHz band  相似文献   
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The purpose of this study is to present three patients with multifocal primary neuroblastoma, to review the literature, and describe the radiographic findings. SUBJECTS AND METHODS: Three children with multifocal neuroblastoma have been identified. The case histories and imaging findings in these patients are reviewed. RESULTS: Two children had synchronous and one child had metachronous multifocal primary neuroblastoma. The primary tumors were both in the abdomen in one patient, both in the chest in another patient, and in the chest and abdomen in the third patient. Evidence for multifocal origin of these tumors, rather than metastatic spread, is presented. CONCLUSION: Multifocal primary neuroblastomas can occur. The tumors maybe synchronous or metachronous. Awareness of this disorder may prevent errors in diagnosis and staging. Although not identified in our patients there is a strong familial incidence of neuroblastomas in those patients with multifocal tumors.  相似文献   
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A predictive analogy of turbulent mass transfer across wavy, sheared air-water interface, in deep water bodies is proposed. The theory is based on the formulation of a theoretical eddy diffusivity profile in the surface region, and it applies to the non-breaking wave regime. The predictions for a water-side friction velocity range of 0.5–6 cm/s are in excellent agreement with laboratory data from wind-wave facilities with an average error of 15.4%.  相似文献   
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We survey the paradigms, approaches and techniques used to conceptualize, define and provide solutions to natural cryptographic problems. We start by presenting some of the central tools (e.g., computational difficulty, pseudorandomness, and zero-knowledge proofs), and next turn to the treatment of encryption and signature schemes. We conclude with an extensive treatment of secure cryptographic protocols both when executed in a stand-alone manner and when many sessions of various protocols are concurrently executed and controlled by an adversary. The survey is intended for researchers in distributed computing, and assumes no prior familiarity with cryptography.Received: June 2001, Accepted: July 2002,  相似文献   
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This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients, whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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