News & notes.

This column presents information of interest to Division 26 members. Included are a candidate's statement from Division member Ludy T. Benjamin, Jr., who is running for President of the American Psychological Association. Also included are a report on the February 1998 Meeting of the APA Council of Representatives; information about the Wallace Russell Fund, nominations for division offices, fellows nominations, and division membership; meeting announcements; and information about access restrictions to the Stanley Milgram papers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cutting edge: novel RNA ligands able to bind CD4 antigen and inhibit CD4+ T lymphocyte function

The value of high affinity-specific reagents in immunology is exemplified by the use of mAbs. Recent in vitro selection methods suggested that oligonucleotides may provide a useful alternative, especially where Abs have been insufficient thus far. We used a systematic evolution of ligands by exponential enrichment (SELEX) procedure to derive high affinity oligonucleotide ligands (aptamers) recognizing CD4. These RNase-resistant aptamers bound with high affinity and specificity as demonstrated using BIAcore (Stevenage, U.K.) technology. They also bound native CD4 on rat lymphocytes and specifically interfered with labeling by high affinity mAbs. All aptamers recognized the same binding site in the CDR2-like region in domain 1 of CD4. The applicability of these aptamers for immunologic studies was clearly demonstrated by their ability to block a fully allogeneic MLR in a CD4-specific manner. The high affinity and stability of aptamers point to their value in the analysis and functional manipulation of the immune system.     

Life span changes in visual enumeration: The number discrimination task.

Participants from 5 groups with mean ages of 6, 8, 10, 22, and 72 yrs were tested on a series of speeded number discriminations: 1 vs 2, 3 vs 4, 6 vs 7, and 8 vs 9. The primary measure of interest (response time slope as a function of number size) decreased with age for numbers in the 1–4 range. However, a U-shaped age function emerged in the 6–9 range, with larger slopes for children and senior adults, and the smallest slopes for young adults. These data suggest that different processes are involved in enumerating small and large numbers of items. It is argued that subitizing, the process for small numbers, makes only minimal demands on spatial attention and thus shows developmental improvements without any decline in old age. In contrast, counting, the process for large numbers, requires sophisticated coordination of spatial attention, which has previously been shown first to improve and then decline over the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of Aging on the Physical-Mechanical Properties of Acrylic Resin Films Cast from Aqueous Dispersions and Organic Solutions

The physical-mechanical properties of the enteric copolymers, poly(methacrylic acid, ethyl acrylate) Eudragit® L100-55, and Eudragit® L30D have been investigated. Free films of the copolymer containing varying levels of glyceryl triacetate (triacetin) and citrate ester (Citroflex®) plasticizers were prepared by both aqueous and solvent casting techniques. Conditioned films were stored at different humidities and temperatures for predetermined time periods prior to testing. Free films with plasticizer concentration ranging from 0 to 30% by weight of the polymer demonstrated that physical aging at room temperature resulted in physical-mechanical changes as the stress-strain curves indicated a decrease in the percent elongation with increases in the tensile strength. Films prepared from the aqueous latex approached a constant state of equilibrium at a faster rate than films prepared from isopropyl alcohol, where the mechanical properties approach a relatively constant value. Free films containing varying amounts of the plasticizer, triethyl citrate, were stored under different humidity and temperature conditions. In addition, a headspace-gas chromatography (HSGC) method was developed to correlate solvent residues with mechanical properties. The results indicated that an increase in temperature and humidity accelerated the rate of solvent evaporation as a function of time. High vacuum and low humidity conditions were demonstrated to be ineffective conditions for solvent removal. Solvent residues were found in all films after 48 hours of exposure to temperatures up to 60°C and/or exposure to relatively high humidity conditions. A direct relationship between plasticizer content and rate of solvent evaporation from the film was established. Higher concentrations of the plasticizer were found to augment the evaporation of the solvents. This enhanced evaporation was due to the stronger molecular interaction forces between the polymer and the plasticizer than between the polymer and the solvent.     

Criteria for good adjustment to chronic hemodialysis: Nurse-patient differences.

Examined nurse–patient agreement on behaviors and attitudes associated with patient adjustment to chronic hemodialysis treatment. 164 hemodialysis nurses and 79 chronic hemodialysis outpatients completed a patient adjustment to dialysis inventory consisting of 43 behaviors and attitudes reported by nurses in earlier research to be important for adjustment to chronic hemodialysis. Results show that over 60% of nurses and patients showed sufficient agreement on the importance of 33 of 43 behaviors and attitudes for patient adjustment in the areas of compliance with the medical regimen, involvement in treatment, patient–staff interactions, and psychological and social functioning. Nurses and patients disagreed as to whether 9 behaviors and attitudes were at least important, while agreeing that only 1 item was irrelevant. Results also show that significantly more patients than nurses rated 25 out of 43 behaviors and attitudes as crucial. Approximately 50% of these related to interacting with staff, family, and friends. It is suggested that social and psychological criteria for adjustment to hemodialysis treatment should be defined by nurses and patients together. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavior of Fe, Mn, Cu and Cd in the duwamish river estuary downstream of a sewage treatment plant

The behavior of dissolved Fe, Mn, Cu and Cd in the Duwamish River downstream of a sewage treatment plant located near Seattle, Washington, was investigated in three distinct zones: (1) immediately downstream of the effluent outfall, (2) further downstream in the freshwater portion of the river and (3) in the estuarine mixing zone. A three-end-member tracer model utilizing salinity and dissolved inorganic nitrogen was developed to distinguish physical mixing processes from biogeochemical reactions. The results of this investigation indicate that Fe was removed from the dissolved phase onto particulates near the plant. Although no additional reactions controlled the distribution of dissolved Fe, Mn and Cu in the freshwater portion of the river, Cd was removed from the dissolved phase. In the estuarine mixing zone, a significant fraction of the dissolved Fe and Cu was removed from solution, while Mn and Cd desorbed from particulates. The chemical forms of the trace metals rather than their sources appear to determine their participation in these reactions.     

Electronic Scanners with Speech Output?A Communication System for the Physically Handicapped And Mentally Retarded

This system employs low-cost electronic symbol scanners and a digital voice synthesizer to enable individuals who are both physically handicapped and mentally retarded to communicate more quickly and effectively.     

"Choice processing in emotionally difficult decisions": Correction.

Reports an error in the article "Choice Processing in Emotionally Difficult Decisions' by Mary Frances Luce, James R. Bettman, and John W. Payne (Journal of Experimental Psychology: Learning, Memory, and Cognition, 1997, Vol. 23, No. 2, pp. 384–405; see record 1997-03378-007). In Table 7 on page 396, the high conflict/low trade-off difficulty mean for the PATTERN variable was printed as -0.13, but the actual mean is 0.13. A portion of the original abstract follows: Extends the standard effort-accuracy approach to explaining task influences on decision processing by arguing that coping goals will interact with effort-minimization goals for negatively emotion-laden decision tasks. These coping goals may involve both a desire to process in a thorough, accurate manner and a desire to avoid particularly distressing aspects of processing. The authors hypothesized and found in 3 experiments that decision processing under increasing negative emotion both becomes more extensive and proceeds more by focusing on one attribute at a time. In particular, increased negative emotion leads to more attribute-based processing at the beginning of the decision process. The results are inconsistent with views that negative emotion acts only as an incentive or only as a source of decision complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)