21,749 research outputs found
Linkages in thermal copolymers of lysine
The thermal copolymerization of lysine with other alpha-amino acids was studied. The identity of the second amino acid influences various properties of the polymer obtained, including the proportion of alpha and epsilon linkages of lysine. A review of linkages in proteinoids indicates alpha and beta linkages for aspartic acid, alpha and gamma linkages for glutamic acid, alpha and epsilon linkages for lysine, and alpha linkages for other amino acids. Thermal proteinoids are thus more complex in types of linkage than are proteins
Study of application of practical performance criteria for the implementation of efficient error-reduction coding Final report
Criteria for implementation of efficient error reduction codin
Incidence of Obesity Among Mentally Retarded Children
An international survey of professionals in the field of mental retardation was conducted to determine significant research priorities in the education of students with mild retardation. A total of 67 individuals responded to survey which represented 83.7% of those contacted. Among the issues rated most highly were two clusters: vocational, career education and post-school adjustment and long term effects and generalization of effects of programs. Implications of the survey data are discussed and recommendations are provided
The Effects of Ethostasis on Farm Animal Behavior: A Theoretical Overview
The solution of animal problems that occur on the farm requires a holistic and multidisciplinary orientation and analysis, as well as the acquisition of new investigatory tools by both veterinarians and animal scientists. Field studies may be modeled under more controlled laboratory conditions, but the most relevant investigations must take place on the farm, and the first level of analysis should be ethological. Domestic animal behavior can be monitored and quantified like any other factor in the animals\u27 environment; yet it has been virtually ignored in the development of new livestock husbandry systems.
The relationships between husbandry systems, disease problems, and behavioral factors are extremely complex but are known to be interrelated and interdependent. It is postulated that severely constricting husbandry practices can generate anomalous behavior- a phenomenon termed ethostasis. Applied ethology now has a vital and central role to play in investigating the problems that have been created by modern intensive livestock production.
The purpose of this overview, therefore, is to delineate some of the husbandry factors that can give rise to behavioral anomalies, and to describe various categories of anomalous behavior that are of diagnostic value in clinical appraisals of stressful husbandry. Ready identification may facilitate recognition and correction of problems that may lead to lowered productivity, diseases, and economic losses; it may also foster concern for the animals\u27 welfare from an ethical, as well as an economic, perspective. These circumstances highlight some of the contemporary animal husbandry problems that warrant further research and quantitative analysis
The Effects of Ethostasis on Farm Animal Behavior: A Theoretical Overview
Ethostasis – the effect of constraining husbandry practices on animal behavior – is described and discussed. The review describes specific husbandry practices that may give rise to behavioral anomalies and how these anomalous behaviors may be of diagnostic value. Ready identification may facilitate correcting problems leading to lower productivity, diseases, and economic losses
The effects of isometric work on heart rate, blood pressure, and net oxygen cost
Isometric exercise effects on heart rate, blood pressure, and net oxygen cos
Understanding Pound-Drever-Hall locking using voltage controlled radio-frequency oscillators: An undergraduate experiment
We have developed a senior undergraduate experiment that illustrates
frequency stabilization techniques using radio-frequency electronics. The
primary objective is to frequency stabilize a voltage controlled oscillator to
a cavity resonance at 800 MHz using the Pound-Drever-Hall method. This
technique is commonly applied to stabilize lasers at optical frequencies. By
using only radio-frequency equipment it is possible to systematically study
aspects of the technique more thoroughly, inexpensively, and free from eye
hazards. Students also learn about modular radio-frequency electronics and
basic feedback control loops. By varying the temperature of the resonator,
students can determine the thermal expansion coefficients of copper, aluminum,
and super invar.Comment: 9 pages, 10 figure
Questions of Political and Economic Integration: Segmentary versus Centralized States Among the Ancient Maya
Nanosecond Pulsed Electric Field Induced Cytoskeleton, Nuclear Membrane and Telomere Damage Adversely Impact Cell Survival
We investigated the effects of nanosecond pulsed electric fields (nsPEF) on three human cell lines and demonstrated cell shrinkage, breakdown of the cytoskeleton, nuclear membrane and chromosomal telomere damage. There was a differential response between cell types coinciding with cell survival. Jurkat cells showed cytoskeleton, nuclear membrane and telomere damage that severely impacted cell survival compared to two adherent cell lines. Interestingly, disruption of the actin cytoskeleton in adherent cells prior to nsPEF exposure significantly reduced cell survival. We conclude that nsPEF applications are able to induce damage to the cytoskeleton and nuclear membrane. Telomere sequences, regions that tether and stabilize DNA to the nuclear membrane, are severely compromised as measured by a pan-telomere probe. Internal pore formation following nsPEF applications has been described as a factor in induced cell death. Here we suggest that nsPEF induced physical changes to the cell in addition to pore formation need to be considered as an alternative method of cell death. We suggest nsPEF electrochemical induced depolymerization of actin filaments may account for cytoskeleton and nuclear membrane anomalies leading to sensitization
Programmability and Performance of Parallel ECS-based Simulation of Multi-Agent Exploration Models
While the traditional objective of parallel/distributed simulation techniques has been mainly in improving performance and making very large models tractable, more recent research trends targeted complementary aspects, such as the “ease of programming”. Along this line, a recent proposal called Event and Cross State (ECS) synchronization, stands as a solution allowing to break the traditional programming rules proper of Parallel Discrete Event Simulation (PDES) systems, where the application code processing a specific event is only allowed to access the state (namely the memory image) of the target simulation object. In fact with ECS, the programmer is allowed to write ANSI-C event-handlers capable of accessing (in either read or write mode) the state of whichever simulation object included in the simulation model. Correct concurrent execution of events, e.g., on top of multi-core machines, is guaranteed by ECS with no intervention by the programmer, who is in practice exposed to a sequential-style programming model where events are processed one at a time, and have the ability to access the current memory image of the whole simulation model, namely the collection of the states of any involved object. This can strongly simplify the development of specific models, e.g., by avoiding the need for passing state information across concurrent objects in the form of events. In this article we investigate on both programmability and performance aspects related to developing/supporting a multi-agent exploration model on top of the ROOT-Sim PDES platform, which supports ECS
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