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Solid‐phase peptide synthesis (SPPS) is widely used to produce peptides. Since its invention, the solid support has enabled the elongation of the synthetic peptide chain. As technologies have evolved, the length of peptide chains accessible with SPPS has grown to that of single‐domain proteins. Resins for SPPS have advanced to improve synthesis capabilities as well. The functionalization of solid supports with polyethylene glycol (PEG) is commonly employed in a range of commercially available resins to aid in the ability to synthesize long or difficult sequences. A notable example of a widely used PEG‐based solid support is ChemMatrix® resin; however, this and several similar resins have recently been discontinued. Here, we demonstrate and compare the capabilities of OctaGel™, ProTide®, and TentaGel XV® resins in synthesizing sequences ranging from peptides to single domain proteins using automated fast‐flow peptide synthesis. Our studies indicate that each resin performs well for routine peptide synthesis by automated flow, whereas TentaGel XV resin showed the best performance for synthesis of difficult or long peptide sequences when comparing quality using yield, purity, and real‐time UV absorbance monitoring during synthesis. [ABSTRACT FROM AUTHOR]

In 2 experiments and a rating study we examined asymmetric transfer of repetition benefit between two easily readable surface forms. Typed second occurrences showed benefit that was similar for words and pseudowords and did not depend on the surface form of the first occurrence. Handwritten second occurrences showed benefit only for words, and benefit was larger when first occurrences were handwritten than when typed. This pattern, which was unrelated to explicit memory, characterized both naming and lexical decision, and benefit transferred between tasks. These results tax current episodic accounts of repetition benefit that are based on retrieving perceptual records or conceptual interpretations, and they tax strongly abstractionist accounts that are based on extremely general visual analysis. A weakly abstractionist account is described, which is based on ease of retrieving category prototypes by instances of varying typicality.

Language/learning disabled (L/LD) and non-disabled (NLD) children were investigated on explicit and implicit tests of memory through tasks of primed picture-naming and item recognition. The presentation format (either pictures or words) and retention intervals of one day or more were the dependent variables. Results showed that L/LD children displayed impaired episodic memory while procedural memory is unaffected.

Whittlesea (1990) reports context specificity in oral rereading. Repetition benefit is larger when a random scrambling of a text is read twice than when two different scramblings are read, indicating an 'episodic' or 'text-level' contribution to repetition benefit. We examine Whittlesea's data by focusing on variability across stimulus materials in the magnitude of context specificity, which ranges from -0.1% to 694.7% of the repetition benefit attributable solely to lexical overlap. We describe similar variability in other recent research, including new work of our own. The central question in the episodic-abstractionist debate is no longer whether context specificity can or cannot be found in rereading but what factors govern the relative contributions of text-level and lexical-level repetition. We offer a 'level of focal attention' hypothesis to supplant the 'task change' hypothesis of Carr, Brown, and Charalambous (1989). The new hypothesis is a strategy-oriented version of transfer-appropriate processing.

Transfer of repetition effects across changes in the context and the surface form of words being read aloud is used to diagnose the degree of abstraction at which perceptual encoding operations take place during reading. Complete transfer is observed for changes from textually coherent to randomly scrambled word order and vice versa in Experiment 1 and for changes from typed to handwritten surface form and vice versa in Experiment 2. Experiment 3 extends the finding of complete transfer across changes in surface form to texts composed of unfamiliar pseudowords, showing that the abstraction effects of the previous experiment do not require lexical familiarity for their occurrence. Experiment 4 further extends this finding to a situation in which readers explicitly expect surface form to remain the same. The results are consistent with a perceptual system in which encoding operations are (a) very abstract with respect to properties of surface form and (b) relatively independent both of higher order comprehension processes, such as syntactic parsing and proposition formation, and of attended expectations about surface properties over which the operations project their categorizations of stimuli. We argue that the perceptual abstraction observed in these experiments depends on overlearned encoding operations established by reading many different instances of the typographical variations typical of a particular writing system.