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991.
Chao Yang Jadhav S.R. Worden R.M. Mason A.J. 《Solid-State Circuits, IEEE Journal of》2009,44(10):2844-2855
With the rapid progress in CMOS compatible microfabrication of biosensors, there is an emerging need to miniaturize biosensor arrays onto the surface of silicon chips that acquire and process sensor data, permitting improved sensitivity, cost and throughput. In this paper, a low power circuit that extracts and digitizes sensor impedance information is presented. Composed of a novel multiplying integrator and a unique bidirectional counter/shifter, the circuit shares resources for impedance extraction and digitization to maximize hardware efficiency. The extremely compact size of the circuit enables the implementation of sensor array microsystems with simultaneous multi-channel readout. Fabricated in 0.5 mum CMOS, the circuit consumes 6 muW at 3 V and occupies only 0.06 mm2, permitting over 100 readout channels within a 3 times 3 mm die. Circuit performance has been verified with a biosensor for gramicidin ion channel embedded in a tethered bilayer lipid membrane. 相似文献
992.
Stephen Mason 《Computer Fraud & Security》2004,2004(8):9-15
993.
In quantitative ultrastructural studies using colloidal gold immunocytochemical techniques, labeling intensities vary according to the size of the probe used. Using postembedded indirect two-sided double labeling and single labeling protocols, the labeling characteristics of four antigens were studied using two probe sizes commonly used in double labeling studies. It was determined that the labeling intensity variation resulting from the use of different probe sizes was unpredictable after correcting for the increased probe size alone. It was possible, however, to obtain comparable labeling densities by first determining the labeling intensities for each probe size with its antigen in single label studies on serial sections and using the same procedure as the double labeling studies. A probe size correction factor for each antigen was calculated from these data. This factor was used to obtain comparable measurements of the relative abundance of each label. 相似文献
994.
Bruce A. Tichenor Zhishi Guo James E. Dunn Leslie E. Sparks Mark A. Mason 《Indoor air》1991,1(1):23-35
The interaction of indoor air pollutants with interior surfaces (i.e., sinks) is a well known, but poorly understood, phenomenon. Studies have shown that re-emissions of adsorbed organic vapours can contribute to elevated concentrations of organics in indoor environments. Research is being conducted in small environmental test chambers to develop data for predicting sink behaviour. This paper reports on the development of sink models based on fundamental mass transfer theory. The results of experiments conducted to determine the magnitude and rate of adsorption and desorption of vapour phase organic compounds for several materials are presented. Five materials were evaluated: carpet, painted wallboard, ceiling tile, window glass, and upholstery. Two organic compounds were tested with each material: tetrachloroethylene (a common cleaning solvent) and ethylbenzene (a common constituent of petroleum-based solvents widely used in consumer products). The results of the experimental work are presented showing the relevant sink effect parameters for each material tested and comparing the sorptive behaviour of the two organic compounds evaluated. An indoor air quality (IAQ) model was modified to incorporate adsorption and desorption sink rates. The model was used to predict the temporal history of the concentration of total vapour phase organics in a test house after application of a wood finishing product. The predicted results are presented and compared to measured values. Suggestions for further research on indoor sinks are presented. 相似文献
995.
A unified framework for traffic control and bandwidth management in ATM networks is proposed. It bridges algorithms for real-time and data services. The central concept of this framework is adaptive connection admission. It employs an estimation of the aggregate equivalent bandwidth required by connections carried in each output port of the ATM switches. The estimation process takes into account both the traffic source declarations and the connection superposition process measurements in the switch output ports. This is done in an optimization framework based on a linear Kalman filter. To provide a required quality of service guarantee, bandwidth is reserved for possible estimation error. The algorithm is robust and copes very well with unpredicted changes in source parameters, thereby resulting in high bandwidth utilization while providing the required quality of service. The proposed approach can also take into account the influence of the source policing mechanism. The tradeoff between strict and relaxed source policing is discussed 相似文献
996.
Responds to a rejoinder by M. S. Blumberg and E. A. Wasserman (see record 83:25924) on Dreger's (see record 83:25925) comments decrying the anthropocentric stance of Blumberg and Wasserman's (see record 1995-20777-001) arguments against mind in creatures lower in the evolutionary scale than human beings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Crits-Christoph Paul; Connolly Mary Beth; Azarian Karen; Crits-Christoph Katherine; Shappell Sandi 《Canadian Metallurgical Quarterly》1996,33(3):418
Conducted a treatment development study applying brief supportive-expressive psychodynamic psychotherapy (P. Crits-Christoph et al; see record 95-195001-002) to the treatment of generalized anxiety disorder (GAD). Background and rationale for the development of this therapy are presented, along with the project's methods and results. Project goals were to develop a treatment manual, train therapists, and assess the treatment's integrity and efficacy. Outcome data on 26 patients (aged 22–64 yrs) with a Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) diagnosis of GAD indicate that the treatment is promising. Patients revealed significant change in anxiety, depression, worry, and interpersonal problems. Ratings of therapist adherence and competence indicate that the treatment manual can be implemented with fidelity and can be discriminated from other treatments. Methodological issues in the planning of treatment research on GAD, particularly the problem of comorbidity, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
The broad spectrum of activity of ciprofloxacin makes it an ideal drug for the prophylaxis of bacterial infections in patients undergoing high-dose chemotherapy (HDC) with autologous stem cell rescue. We present two cases of ciprofloxacin-associated acute renal failure (ARF) in patients undergoing HDC. Maintaining a high index of suspicion for this complication will allow a prompt diagnosis, with discontinuation of the drug usually resulting in a reversal of renal failure. Renal biopsy usually reveals changes compatible with interstitial nephritis, but is not always possible in these patients due to severe thrombocytopenia following HDC. A brief course of steroid therapy may be beneficial although the role of glucocorticoids is difficult to ascertain in the absence of data regarding its efficiency in this clinical setting. 相似文献
999.
Daniel C Liebler Beau T Hansen Sean W Davey Laura Tiscareno Daniel E Mason 《Analytical chemistry》2002,74(1):203-210
We have developed a pattern recognition algorithm called SALSA (scoring algorithm for spectral analysis) for the detection of specific features in tandem MS (MS-MS) spectra. Application of the SALSA algorithm to the detection of peptide MS-MS ion series enables identification of MS-MS spectra displaying characteristics of specific peptide sequences. SALSA analysis scores MS-MS spectra based on correspondence between theoretical ion series for peptide sequence motifs and actual MS-MS product ion series, regardless of their absolute positions on the m/z axis. Analyses of tryptic digests of bovine serum albumin (BSA) by LC-MS-MS followed by SALSA analysis detected MS-MS spectra for both unmodified and multiple modified forms of several BSA tryptic peptides. SALSA analysis of MS-MS data from mixtures of BSA and human serum albumin (HSA) tryptic digests indicated that ion series searches with BSA peptide sequence motifs identified MS-MS spectra for both BSA and closely related HSA peptides. Optimal discrimination between MS-MS spectra of variant peptide forms is achieved when the SALSA search criteria are optimized to the target peptide. Application of SALSA to LC-MS-MS proteome analysis will facilitate the characterization of modified and sequence variant proteins. 相似文献
1000.