High-performance FPGA implementation of DES using a novel method for implementing the key schedule

A generic, parameterisable key scheduling core is presented, which can be utilised in pipelinable private-key encryption algorithms. The data encryption standard (DES) algorithm, which lends itself readily to pipelining, is utilised to exemplify this novel key scheduling method and the broader applicability of the method to other encryption algorithms is illustrated. The DES design is implemented on Xilinx Virtex FPGA technology. Utilising the novel method, a 16-stage pipelined DES design is achieved, which can run at an encryption rate of 3.87 Gbit/s. This result is among the fastest hardware implementations and is a factor 28 times faster than software implementations.

Assessing the effectiveness of a DRA versus DRA with an activity schedule procedure on the reduction of problem behaviour

Differential Reinforcement of Alternative behaviour (DRA) (Athens & Vollmer, 2010; Cooper, Heron, & Heward, 2007) is a procedure that consists in withholding reinforcement for the targeted inappropriate behaviour while reinforcing behaviours, i.e., that have the same function, but socially more acceptable topographies. DRA has repeatedly proven to be effective in reducing problem behaviours in individuals with autism (Campbell, 2003). On the other hand, a number of single-subject research studies have provided evidence for the use of activity schedules as a means to decrease aggressive behaviour (Dooley et al., 2001; Flannery & Hemer, 1994; Lalli, Casey, Goh, & Merlinoet al., 1994). The purpose of the present study was to evaluate the effectiveness of DRA in combination with the use of an activity schedule. We compared the impact of the visual activities schedule used in combination with a DRA procedure versus the impact of the DRA procedure used alone on problem behaviour of a boy diagnosed with an Autism Spectrum Disorder. An alternating treatments design was used to compare the rate of behaviour problems in each of the two treatment conditions. DRA was delivered as treatment A, while the combination of the activities schedule and DRA was treatment B.

Behavioural and histopathological analyses of ibuprofen treatment on the effect of aggregated AB (1-42) injections in the rat

It has been suggested that inflammatory processes may play a role in the development of Alzheimerâ??s disease (AD), and that nonsteroidal anti-inflammatory drug treatments may provide protection against the onset of AD. In the current study male Wistar rats were trained in two-lever operant chambers under an alternating lever cyclic-ratio ratio (ALCR) schedule. When responding showed no trends, subjects were divided into groups. One group was bilaterally injected into the CA3 area of the hippocampus with 5 μl of aggregated β-amyloid (Aβ) suspension, and one group was bilaterally injected into the CA3 area of the hippocampus with 5 μl of sterile saline. Subgroups were treated twice daily with 0.1 ml (40 mg/kg) ibuprofen administered orally. The results indicated that chronic administration of ibuprofen protected against detrimental behavioural effects following aggregated Aβ injections. Withdrawal of ibuprofen treatment from aggregated Aβ-injected subjects produced a decline in behavioural performance to the level of the non-treated aggregated Aβ-injected group. Ibuprofen treatment reduced the numbers of reactive astrocytes following aggregated Aβ injection, and withdrawal of ibuprofen resulted in an increase of reactive astrocytes. These results suggest that induced inflammatory processes may play a role in AD, and that ibuprofen treatment may protect against some of the symptoms seen in AD.

An operant determination of the behavioural mechanism of benzodiazepine enhancement of food intake

Rationale A recent review paper by Cooper (Appetite 44:133–150, 2005) has pointed out that a role for benzodiazepines as appetite stimulants has been largely overlooked. Cooper’s review cited several studies that suggested the putative mechanism of enhancement of food intake after benzodiazepine administration might involve increasing the perceived pleasantness of food (palatability). Objectives The present study examined the behavioral mechanism of increased food intake after benzodiazepine administration. Materials and methods The cyclic-ratio operant schedule has been proposed as a useful behavioral assay for differentiating palatability from regulatory effects on food intake (Ettinger and Staddon, Physiol Behav 29:455–458, 1982 and Behav Neurosci 97:639–653, 1983). The current study employed the cyclic-ratio schedule to determine whether the effects on food intake of chlordiazepoxide (CDP) (5.0 mg/kg), sodium pentobarbital (5.0 mg/kg), and picrotoxin (1.0 mg/kg) were mediated through palatability or regulatory processes. Results The results of this study show that both the benzodiazepine CDP and the barbiturate sodium pentobarbital increased food intake in a manner similar to increasing the palatability of the ingestant, and picrotoxin decreased food intake in a manner similar to decreasing the palatability of the ingestant. Conclusions These results suggest that the food intake enhancement properties of benzodiazepines are mediated through a mechanism affecting perceived palatability.