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C8H10N2O2, orthorhombic, Pbca (no. 61), a = 11.0571(2) Å, b = 8.1172(2) Å, c = 17.6080(4) Å, V = 1580.37(6) Å3, Z = 8, R gt(F) = 0.0324, wR ref(F 2) = 0.0872, T = 100(2) K.

The synthesis of glycopolymers by copolymerising an allyl glucosamine (AG) monomer with co-monomers methyl methacrylate (MMA), acrylonitrile (AN) and 2-hydroxyethyl methacrylate (HEMA) was investigated via free-radical polymerisation of 2,2-azobisisobutyronitrile (AIBN) in dimethylformamide (DMF). Three new copolymers, poly(AG-co-MMA), poly(AG-co-AN) and poly(AG-co-HEMA), were obtained. The chemical structures of the glycopolymers were analysed using 1H-NMR, 13C-NMR and FTIR. The thermal properties and degradation kinetics of the three glycopolymers were examined by thermogravimetric (TG) analysis at different heating rates. The effects of different co-monomers on the copolymerisation yield, thermal properties and biological activities of the resulting glycopolymers were investigated. The activation energies of the decomposition stages were calculated using the Flynn–Wall–Ozawa (FWO) and Kissinger methods. Furthermore, the biological activity of AG monomers and glycopolymers was studied and compared to chitosan. Poly(AG-co-HEMA) had the most significant effect on MCF-7 cell viability, and all glycopolymers have a low toxic effect profile on MCF-7 cell lines. [ABSTRACT FROM AUTHOR]

Adults with autism spectrum disorder (ASD) show intact recognition (supported procedure) but impaired recall (unsupported procedure) of incidentally-encoded context. Because this has not been demonstrated for temporal source, we compared the temporal and spatial source memory of adults with ASD and verbally matched typical adults. Because of difficulties with temporal processing in ASD, we predicted ASD adults would benefit from test support for location but not temporal occurrence of studied words. We found similar levels of recognition and source memory for both groups but there was a greater effect of support on memory for location source in the ASD group. The lack of an effect of support for temporal source may simply reflect a difficulty in operationalising temporal cues.

Rehearsal strategies of adults with autism spectrum disorders (ASDs) and demographically matched typically developed (TD) adults were strategically manipulated by cueing participants to either learn, or forget each list word prior to a recognition task. Participants were also asked to distinguish between autonoetic and noetic states of awareness using the Remember/Know paradigm. The ASD group recognised a similar number of to-be-forgotten words as the TD group, but significantly fewer to-be-learned words. This deficit was only evident in Remember responses that reflect autonoetic awareness, or episodic memory, and not Know responses. These findings support the elaborative encoding deficit hypothesis and provide a link between the previously established mild episodic memory impairments in adults with high functioning autism and the encoding strategies employed.

Diminished episodic memory and diminished use of semantic information to aid recall by individuals with autism spectrum disorder (ASD) are both thought to result from diminished relational binding of elements of complex stimuli. To test this hypothesis, we asked high-functioning adults with ASD and typical comparison participants to study grids in which some cells contained drawings of objects in non-canonical colours. Participants were told at study which features (colour, item, location) would be tested in a later memory test. In a second experiment, participants studied similar grids and were told that they would be tested on object-location or object-colour combinations. Recognition of combinations was significantly diminished in ASD, which survived covarying performance on the "Color Trails Test" (D'Elia et al. "Color trails test. Professional manual." "Psychological Assessment Resources," Lutz, 1996), a test of executive difficulties. The findings raise the possibility that medial temporal as well as frontal lobe processes are dysfunctional in ASD.

To test the effects of providing relational cues at encoding and/or retrieval on multi-trial, multi-list free recall in adults with high-functioning autism spectrum disorder (ASD), 16 adults with ASD and 16 matched typical adults learned a first followed by a second categorised list of 24 words. Category labels were provided at encoding, retrieval, both or not at all. Both groups showed enhanced recall when labels were available during encoding or throughout the task. ASD individuals showed reduced recall of the second list and reduced clustering. Clustering and recall were correlated in both groups, which also showed similar levels of subjective organisation. The findings are discussed in relation to theories of frontal and medial temporal lobe contributions to memory in ASD.

The "Task Support Hypothesis" (TSH, Bowler et al. Neuropsychologia 35:65-70 1997) states that individuals with autism spectrum disorder (ASD) show better memory when test procedures provide support for retrieval. The present study aimed to see whether this principle also applied at encoding. Twenty participants with high-functioning ASD and 20 matched comparison participants studied arrays of 112 words over four trials. Words were arranged either under hierarchically embedded category headings (e.g. Instruments-String-Plucked-Violin) or randomly. Both groups showed similar overall recall and better recall for the hierarchically organised words. However, the ASD participants made less use of information about relations between words and more use of item-specific information in their recall, confirming earlier reports of relational difficulties in this population.

Single trial methods reveal unimpaired free recall of unrelated words in Asperger's syndrome (AS). When repeated trials are used (free recall learning), typical individuals show improved recall over trials, subjective organization of material (SO) and a correlation between free recall and SO. We tested oral (Experiment 1) and written (Experiment 2) free recall over 16 trials in adults with AS and typical individuals. Across both experiments AS participants showed marginally diminished recall. Poorer SO was seen in the Asperger group only in Experiment 2, but in both experiments, individual differences in SO in the Asperger group were less likely to converge over trials. This lack of convergence suggests that the AS group organize material in idiosyncratic ways.

Memory in autism spectrum disorder (ASD) is characterised by greater difficulties with recall rather than recognition and with a diminished use of semantic or associative relatedness in the aid of recall. Two experiments are reported that test the effects of item-context relatedness on recall and recognition in adults with high-functioning ASD (HFA) and matched typical comparison participants. In both experiments, participants studied words presented inside a red rectangle and were told to ignore context words presented outside the rectangle. Context words were either related or unrelated to the study words. The results showed that relatedness of context enhanced recall for the typical group only. However, recognition was enhanced by relatedness in both groups of participants. On a behavioural level, these findings confirm the Task Support Hypothesis [Bowler, D. M., Gardiner, J. M., & Berthollier, N. (2004). Source memory in Asperger's syndrome. "Journal of Autism and Developmental Disorders, 34", 533-542], which states that individuals with ASD will show greater difficulty on memory tests that provide little support for retrieval. The findings extend this hypothesis by showing that it operates at the level of relatedness between studied items and incidentally encoded context. By showing difficulties in memory for associated items, the findings are also consistent with conjectures that implicate medial temporal lobe and frontal lobe dysfunction in the memory difficulties of individuals with ASD. (Contains 2 tables and 2 figures.)

The authors investigated depth-of-processing effects on conceptual priming by comparing incidental (implicit) and intentional (explicit) tests of word association. In Experiment 1, depth of processing at study influenced priming of weak and medium associates but not of strong associates. In Experiment 2, depth of processing influenced priming of weak associates but not of compound phrases (e.g., coathanger), whose preexperimental association strength matched that of weak associates. In Experiment 3, the same pattern persisted when study was auditory and test was visual, ensuring that priming was conceptual and not perceptual. In all experiments, in matched intentional tests, depth-of-processing effects occurred for all association strengths and for both phrases and associates, suggesting that the incidental tests were uncontaminated by voluntary retrieval, because they showed depth-of-processing effects only for some materials and not others, within the same participants and tests. Because depth-of-processing effects on involuntary free-association priming depend on the presence versus absence of a cohesive preexperimental representation, the memory-systems and conceptual/perceptual processing approaches to memory-test dissociations require modification to account for component processes of conceptual priming.

Free recall in adults with Asperger's Syndrome (AS) was compared with that in matched controls in an experiment including semantically similar, phonologically similar and unrelated word lists. Without supportive instructions, adults with AS were significantly impaired in their recall of phonologically and semantically related lists, but not unrelated lists. Even when trained to make use at study of the relations among the words, the adults with AS recalled fewer words than the control group. Participants rehearsed the study lists out loud and the rehearsal data was analysed. Despite a very slight trend for adults with AS to engage in less elaborative rehearsal and more rote rehearsal, their rehearsal did not differ significantly from that of controls.

Memory difficulties in autism are observed mainly on measures like free recall, where test procedures provide no support for memory. When support is present, such as in cued recall, difficulties are less evident. Such observations may explain the mixed findings on source memory in autism. Bennetto, Pennington and Rogers (Child Development, 67, 1816-1835) found increased earlier-list intrusions in a multi-list free-recall paradigm (support absent), yet Farrant, Blades and Boucher (Journal of Autism and Developmental Disorders, 28, 43-50) reported no impairment in identification of who had spoken a particular word at study (support present). We tested the effects on source memory of presence or absence of support for source in participants with Asperger's syndrome. The Asperger participants' overall deficit in source memory was largely eliminated when source was supported at test.

A study compared 16 adults with Asperger syndrome and 10 controls in remember versus know recognition memory. Both groups showed superior recognition for low-frequency compared with high-frequency words. Recognition in the individuals with Asperger syndrome was associated with less remembering and more knowing than in the control group. (Contains references.) (Author/CR)

N-Acylhydrazones 11-17 were prepared via reaction of 2-hydroxy-3,5-dinitrobenzohydrazide 3 with aromatic aldehydes 4-6 or with aromatic ketone 7 or aliphatic acyclic ketone 8 and cyclic aliphatic ketones 9-10 under reflux in ethanol. Conversion of hydrazide hydrazone 17 into N-acetyl-1,3,4-oxadiazole derivative 19 was achieved via reaction with acetic anhydride 18. The products were characterized by MS, ¹H-NMR and 13C-NMR. The structure of 19 was confirmed by X-ray analysis. Compound 19 was evaluated for in vitro antibacterial activity against two microorganisms (S. aureus and E. coli ). The obtained results showed that this compound has good inhibition against the tested bacterial pathogens by micro-dilution method with MIC 15.1 μg. [ABSTRACT FROM AUTHOR]

We describe two experiments that tested the prediction that distinctive forenames would be better recognized than typical forenames and which investigated whether this distinctiveness effect, if obtained, occurred in subjective experiences of the recollective or familiarity components of recognition memory. To that end, the remember-know paradigm was used to measure people's experiences of recollection or familiarity. The results revealed that distinctive forenames were more memorable than typical forenames and that that this distinctiveness effect was present only in the subjective experience of remembering. Additionally, the present research showed that these distinctiveness effects were present after retention intervals of both 1 and 7 days. These results replicate and extend past research on distinctiveness effects and also provide support for Rajaram's (1996) distinctiveness-fluency account of the 2 states of subjective awareness., The distinctiveness effect The distinctiveness effect is the common finding that compared with typical or expected items, distinctive or unexpected items are more memorable (Cohen & Carr, 1975; Dewhurst & [...]