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The objective of this study was to evaluate the efficacy of buffered vinegar in a marinade solution on inhibiting Listeria monocytogenes growth on cooked broiler breast meat. Broiler breasts were vacuum-tumbled for 30 min in a marinade consisting of dry (0%, 0.4% DV, 0.6%DV, and 0.8%) or liquid vinegar (1.5%), sodium chloride, sodium tripolyphospate, and water. The chicken breasts were then cooked to an internal temperature of 75°C. The breast meat was inoculated with L. monocytogenes, placed into modified atmosphere packaging, and stored at 2°C plus/minus 2 for 0-60 days. L. monocytogenes growth was stable on treatments for up to 30 days. However, from 35 to 60 days, the buffered vinegar treatments had fewer L. monocytogenes counts (P<0.05) than the control treatment. In addition, the 0.8 % DV and 1.5 % LV treatments had fewer than 2.0 log counts of L. monocytogenes after 60 days of storage.

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This research evaluates the effectiveness of a concentrated, buffered vinegar product (CBV) and a simple buffered vinegar product (BV) for controlling Clostridium perfringens outgrowth during extended cooling times of ready-to-eat roast turkey and roast beef respectively. Whole turkey breasts and beef inside rounds were injected with a typical brine, then ground and mixed with CBV (0.0, 2.01, 2.70 and 3.30% wt/wt) or BV (0.0, 1.75, 2.25, and 3.75% wt/wt) and a three-strain C. perfringens spore cocktail to a detectable level of ca. 2-3 log CFU/g. The meat was divided into 10g portions and vacuum packaged and stored frozen until tested. The meat was cooked in a programmable water bath to 71.6°C (160.8°F) in 5 hours. The meat was then cooled exponentially with the times between 48.9°C and 12.8°C (120°F and 55°F) lasting 6, 9, 12, 15, and 18 hours for the five different cooling treatments. The cooling continued until the temperature reached 4.4°C (40°F). C. perfringens counts were taken at 54.4°C (130°F) and 4.4°C (40°F). At a 2.01% concentration, CBV effectively limited C. perfringens growth to 1-log or less up to a 9-hour cooling treatment, while 2.70 and 3.30% concentrations were effective up to the 18 hour cooling treatment. BV had an inhibitory effect on C. perfringens outgrowth in roast beef, but did not limit growth to 1-log or less at any concentration tested for any of the cooling treatments.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Owing to rapid development of PC industry, personal computer has been surprisingly improved on reliability and speed and it has been applied to many fields, such as aerospace, satellite and telemetry applications. As we all known, two aspects decide how fast the PC-based data acquisition can be reached. One aspect is CPU processing and the other is I/O bandwidth. Indeed, the first aspect has changed increasingly insignificant because the frequency of CPU has exceeded 700MHz which can satisfy fully the need of high rate data processing. So I/O bandwidth is the only key factor of the high rate PC-based data acquisition and we must adopt efficient data buffer techniques to satisfy the demand of telemetry data entry. This paper presents a buffered data channel which use memory mapping, EPLD and Dual-Port SRAM techniques. The operation platform of this design is WINDOWS95/98 and the software includes device driver and real-time processing routines.

This work introduces fundamental knowledge of EMI, and presents three basic features correlated to EMI susceptibility: nonlinear distortion, asymmetric slew rate (SR) and parasitic capacitance. Different existing EMI-resisting techniques are analyzed and compared to each other in terms of EMI-Induced input offset voltage and other important specifications such as current consumption. In this work, EMI-robust analog circuits are proposed, of which the architecture is based on source-buffered differential pair in the previous publications. The EMI performance of the proposed topologies has been verified within a test IC which was fabricated in NCSU 0.5um CMOS technology. Experimental results are presented when an EMI disturbance signal of 400mV and 800mV amplitude was injected at the input terminals, and compared with a conventional and an existing topology. The tested maximal EMI-induced input offset voltage corresponds to -222mV for the new structure, which is compared to -712mV for the conventional one and -368mV for the one using existing source-buffered technique in literature. Furthermore the overall performances of the circuits such as current consumption or input referred noise are also provided with the corresponding simulation results.

Cognitive radio networks (CRN) have been tipped as one of the most promising paradigms for next generation wireless communication, due primarily to its huge promise of mitigating the spectrum scarcity challenge. To help achieve this promise, CRN develop mechanisms that permit spectrum spaces to be allocated to, and used by more than one user, either simultaneously or opportunistically, under certain preconditions. However, because of various limitations associated with CRN, spectrum and other resources available for use in CRN are usually very scarce. Developing appropriate models that can efficiently utilise the scarce resources in a manner that is fair, among its numerous and diverse users, is required in order to achieve the utmost for CRN. 'Resource allocation (RA) in CRN' describes how such models can be developed and analysed. In developing appropriate RA models for CRN, factors that can limit the realisation of optimal solutions have to be identified and addressed; otherwise, the promised improvement in spectrum/resource utilisation would be seriously undermined. In this thesis, by a careful examination of relevant literature, the most critical limitations to RA optimisation in CRN are identified and studied, and appropriate solution models that address such limitations are investigated and proffered. One such problem, identified as a potential limitation to achieving optimality in its RA solutions, is the problem of heterogeneity in CRN. Although it is indeed the more realistic consideration, introducing heterogeneity into RA in CRN exacerbates the complex nature of RA problems. In the study, three broad classifications of heterogeneity, applicable to CRN, are identified; heterogeneous networks, channels and users. RA models that incorporate these heterogeneous considerations are then developed and analysed. By studying their structures, the complex RA problems are smartly reformulated as integer linear programming problems and solved using classical optimisation. This smart move makes it possible to achieve optimality in the RA solutions for heterogeneous CRN. Another serious limitation to achieving optimality in RA for CRN is the strictness in the level of permissible interference to the primary users (PUs) due to the activities of the secondary users (SUs). To mitigate this problem, the concept of cooperative diversity is investigated and employed. In the cooperative model, the SUs, by assisting each other in relaying their data, reduce their level of interference to PUs significantly, thus achieving greater results in the RA solutions. Furthermore, an iterative-based heuristic is developed that solves the RA optimisation problem timeously and efficiently, thereby minimising network complexity. Although results obtained from the heuristic are only suboptimal, the gains in terms of reduction in computations and time make the idea worthwhile, especially when considering large networks. The final problem identified and addressed is the limiting effect of long waiting time (delay) on the RA and overall productivity of CRN. To address this problem, queueing theory is investigated and employed. The queueing model developed and analysed helps to improve both the blocking probability as well as the system throughput, thus achieving significant improvement in the RA solutions for CRN. Since RA is an essential pivot on which the CRN's productivity revolves, this thesis, by providing viable solutions to the most debilitating problems in RA for CRN, stands out as an indispensable contribution to helping CRN realise its much-proclaimed promises. / Thesis (PhD)--University of Pretoria, 2017. / Electrical, Electronic and Computer Engineering / PhD / Unrestricted

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Potato production requires high phosphorus (P) application with potential negative environmental or nutritional consequences for potato as well as for subsequent crops. Impacts of high available P on yield and plant nutrition of species in potato cropping rotations are inadequately understood, and could result in antagonistic interactions with cationic micronutrients such as zinc (Zn) and manganese (Mn). Three hydroponic experiments were conducted with Russet Burbank potato to elucidate P and Zn relationships and associated interactions with other nutrients. In the first experiment, P solution concentration was constant at 256 µM while Zn concentration varied: 0.1, 2, 6, 18, 54, 162 and 456 µM Zn. In the second, Zn solution concentration was constant at 6 µM while P concentration varied: 32, 64, 128, 256, 512, 1024 and 2048 µM P. In the third, three levels of P and Zn varied in all possible combinations: 32, 128 and 1024 µM P and 0.1, 54 and 486 µM Zn. As expected, Zn increased in all plant parts with increasing old shoots while root P increased. This suggests a P-Zn complex formation in roots preventing movement of P to the shoots of plants under high Zn. This was confirmed under variable P and Zn. Contrary to expectations, a direct impact of increased solution P on Zn uptake or distribution in potato was not observed except at 486 µM Zn in the third experiment. Increased solution P at low Zn levels resulted in a steep increase of P in new and old shoot growth and an accumulation of Mn in potato roots—factors that might indirectly impact Zn nutrition in potato. Although high P levels in potato did not directly reduce Zn content or cause Zn deficiency, excessive P accumulation with insufficient Zn may reduce the activity of Zn by interacting with other micronutrients such as Mn.