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Biomedical subjects

R C Lindsay

Publications and source records attributed to R C Lindsay.

At least 19 recordsLinked to original sources

A preidentification questioning effect: serendipitously increasing correct rejections.

A study designed to test the effects of delay between crime and lineup on identification accuracy produced an unusually high rate of correct rejection from target-absent, simultaneous lineups (J. E. Dysart, 1999). Examining the procedures indicated that one question included in a preidentification questionnaire differed from those used previously. The question asked witnesses if they believed they would be able to correctly reject a target-absent lineup. An experiment (N = 138) was conducted to explore the impact of preidentification questions, including this new question, on witness accuracy. Results revealed that asking witnesses these questions, prior to viewing the lineup, significantly increased correct rejections of target-absent simultaneous lineups.

Crime↗

Eyewitness accuracy rates in sequential and simultaneous lineup presentations: a meta-analytic comparison.

Most police lineups use a simultaneous presentation technique in which eyewitnesses view all lineup members at the same time. Lindsay and Wells (R. C. L. Lindsay & G. L. Wells, 1985) devised an alternative procedure, the sequential lineup, in which witnesses view one lineup member at a time and decide whether or not that person is the perpetrator prior to viewing the next lineup member. The present work uses the technique of meta-analysis to compare the accuracy rates of these presentation styles. Twenty-three papers were located (9 published and 14 unpublished), providing 30 tests of the hypothesis and including 4,145 participants. Results showed that identification of perpetrators from target-present lineups occurs at a higher rate from simultaneous than from sequential lineups. However, this difference largely disappears when moderator variables approximating real world conditions are considered. Also, correct rejection rates were significantly higher for sequential than simultaneous lineups and this difference is maintained or increased by greater approximation to real world conditions. Implications of these findings are discussed.

Bias↗

Mug shot exposure prior to lineup identification: interference, transference, and commitment effects.

The effects of viewing mug shots on subsequent identification performance are as yet unclear. Two experiments used a live staged-crime paradigm to determine if interpolated eyewitness exposure to mug shots caused interference, unconscious transference, or commitment effects influencing subsequent lineup accuracy. Experiment 1 (N = 104) tested interference effects. Similar correct decision rates were obtained for the mug shot and no mug shot groups from both perpetrator-present and absent lineups. Experiment 2 (N = 132) tested for commitment and transference effects. Results showed that the commitment group made significantly more incorrect identifications than either the control or the transference group, which had similar false-identification rates. Commitment effects present a serious threat to identification accuracy from lineups following mug shot searches.

Adult↗

From the lab to the police station. A successful application of eyewitness research.

The U.S. Department of Justice released the first national guide for collecting and preserving eyewitness evidence in October 1999. Scientific psychology played a large role in making a case for these procedural guidelines as well as in setting a scientific foundation for the guidelines, and eyewitness researchers directly participated in writing them. The authors describe how eyewitness researchers shaped understanding of eyewitness evidence issues over a long period of time through research and theory on system variables. Additional pressure for guidelines was applied by psychologists through expert testimony that focused on deficiencies in the procedures used to collect the eyewitness evidence. DNA exoneration cases were particularly important in leading U.S. Attorney General Janet Reno to notice the eyewitness literature in psychology and to order the National Institute of Justice to coordinate the development of national guidelines. The authors describe their experience as members of the working group, which included prosecutors, defense lawyers, and law enforcement officers from across the country.

Expert Testimony↗

Postdictors of eyewitness errors: can false identifications be diagnosed?

Eyewitness researchers have "postdicted" identification accuracy using witness confidence (S. L. Sporer, S. Penrod, D. Read, & B. Cutler, 1995), response latency (S. L. Sporer, 1993, 1994), and endorsement of statements consistent with using relative versus absolute judgment strategies (D. Dunning & L. B. Stern, 1994; R. C. L. Lindsay & K. Bellinger, 1999). All of these measures were collected from 321 introductory psychology students who had viewed a staged crime and completed a lineup identification task. Some participants received feedback after identification (G. L. Wells & A. L. Bradfield, 1998). Lineup fairness was also used as a postdictor of eyewitness accuracy. Discriminant function analysis indicated that 75.2% of choosers and 63.0% of nonchoosers were correctly classified. Decision time and lineup fairness were the best postdictors of accuracy. The implications for postdicting real eyewitness decisions are discussed.

Crime↗

Alternatives to the sequential lineup: the importance of controlling the pictures.

Because sequential lineups reduce false-positive choices, their use has been recommended (R. C. L. Lindsay, 1999; R. C. L. Lindsay & G. L. Wells, 1985). Blind testing is included in the recommended procedures. Police, concerned about blind testing, devised alternative procedures, including self-administered sequential lineups, to reduce use of relative judgments (G. L. Wells, 1984) while permitting the investigating officer to conduct the procedure. Identification data from undergraduates exposed to a staged crime (N = 165) demonstrated that 4 alternative identification procedures tested were less effective than the original sequential lineup. Allowing witnesses to control the photographs resulted in higher rates of false-positive identification. Self-reports of using relative judgments were shown to be postdictive of decision accuracy.

Crime↗

Identification accuracy of children versus adults: a meta-analysis.

Identification accuracy of children and adults was examined in a meta-analysis. Preschoolers (M = 4 years) were less likely than adults to make correct identifications. Children over the age of 5 did not differ significantly from adults with regard to correct identification rate. Children of all ages examined were less likely than adults to correctly reject a target-absent lineup. Even adolescents (M = 12-13 years) did not reach an adult rate of correct rejection. Compared to simultaneous lineup presentation, sequential lineups increased the child-adult gap for correct rejections. Providing child witnesses with identification practice or training did not increase their correct rejection rates. Suggestions for children's inability to correctly reject target-absent lineups are discussed. Future directions for identification research are presented.

Adolescent↗

Using mug shots to find suspects.

The authors examined the use of mug shots as an investigative tool. Data are reported from 3 staged-crime experiments (N = 365) exploring the effects on mug-shot selections of number of faces seen before the confederate criminal's, of biased procedures, and of sorting pictures to fit the description of the criminal. The confederate was frequently selected from mug shots, and few innocent people were selected. Selections of faces declined with number of pictures viewed before the confederate's. Biased instructions and clothing bias increased choices of innocent people but not of guilty people. More innocent faces were selected when the pictures matched the confederate's description than when the pictures were not sorted to match the confederate's description. Viewing mug shots had no effect on subsequent identifications in lineups. Implications for police use of mug shots are discussed.

Adult↗

Release of volatile branched-chain and other fatty acids from ruminant milk fats by various lipases.

Bovine, ovine, and caprine milk fats were treated with pregastric lipases (kid goat, calf, and lamb), microbial lipases (Candida cylindracea, C. cylindracea AY30, Aspergillus niger APF12, Rhizopus arrhizus, Penicillium roqueforti R10, and Mucor zavanicus Map 10), porcine pancreatic lipase, or milk lipase. All three pregastric lipases preferentially hydrolyzed volatile branched-chain and short n-chain fatty acids from each milk fat. Pregastric lipases also released a relatively low proportion of C10 from bovine milk fats but a high proportion of C10 from caprine milk fat. Milk lipase released very low concentrations of butanoic acid and did not release 4-methyloctanoic acid in significant amounts except from caprine milk fat. Ovine milk fat yielded a substantially greater concentration of butanoic acid than did bovine or caprine milk fats when it was hydrolyzed by porcine pancreatic lipase. Candida cylindracea lipase yielded high amounts of volatile n-chain fatty acids nonselectively and only small quantities of volatile branched-chain fatty acids. High amounts of the medium-chain branched fatty acids were produced by kid goat, P. roqueforti, A. niger, and R. arrhizus lipases.

Animals↗

Performance of selected milk fat fractions in cold-spreadable butter.

Based on solid fat content profiles, milk fat fractions produced by fractional crystallization procedures employing melted milk fat and milk fat dissolved in acetone were selected for incorporation into soft butter samples. Butter samples made from low melting liquid fractions or a combination of primarily low melting liquid fractions and a small amount of high melting solid fractions exhibited good spreadability at refrigerator temperature (4 degrees C) but were almost melted at room temperature (21 degrees C). Butters made with a high proportion of low melting liquid fraction, a small proportion of high melting solid, and a small proportion of very high melting solid fractions were still spreadable at refrigerator temperature and maintained their physical form at room temperature. Very high melting fractions, which provided key structural functionality in spreadable butter, were obtained from acetone fractionation. Because the use of acetone in processing may hinder or prevent commercialization of these fractions, other means to obtain very high melting fractions from milk fat should be pursued.

Animals↗

Biased lineups: sequential presentation reduces the problem.

Biased lineups have been shown to increase significantly false, but not correct, identification rates (Lindsay, Wallbridge, & Drennan, 1987; Lindsay & Wells, 1980; Malpass & Devine, 1981). Lindsay and Wells (1985) found that sequential lineup presentation reduced false identification rates, presumably by reducing reliance on relative judgment processes. Five staged-crime experiments were conducted to examine the effect of lineup biases and sequential presentation on eyewitness recognition accuracy. Sequential lineup presentation significantly reduced false identification rates from fair lineups as well as from lineups biased with regard to foil similarity, instructions, or witness attire, and from lineups biased in all of these ways. The results support recommendations that police present lineups sequentially.

Adult↗

Environmental and industrial factors relating to flavor tainting of fish in the upper Wisconsin river.

Extracts from Large Toothed Aspen (Populous grandidenta Michx.) and Jack Pine (Pinus banksiana Lamb.) contained many odor compounds found in flavor-tainted walleye from the Wisconsin River, including alkylphenols. Aspen wood contained 8 ppb of 2-isopropylphenol, and river sediments also contained low ppb levels of many alkylphenols, including 2-isopropylphenol. Thiophenol and thiocresol which sporadically cause offensive sulfury taints in Wisconsin River fish were also found in river sediment. Quantitative analysis of fish for alkylphenols supported a hypothesis involving a food chain-mediated seasonal fluctuation of alkylphenol levels in fish. Thiophenols are postulated to be derived from pulp mill activities on the river.

Animals↗

Toxicological properties of thio- and alkylphenols causing flavor tainting in fish from the upper Wisconsin River.

EC50 Microtox (5 min, 25 degrees C) assay values for 2-isopropylphenol, 3-isopropylphenol, 4-isopropylphenol, 2,4-diisopropylphenol, 2,5-diisopropylphenol 2,6-diisopropylphenol, 3,5-diisopropylphenol, carvacrol, thymol, thiophenol, and thiocresol ranged from 2 x 10(-2) mM for thymol (least toxic) to 2 x 10(-4) mM for 2,4-diisopropylphenol and 4-isopropylphenol (most toxic).

Alkylation↗

Inhibition of trout gill and soybean lipoxygenases by organotin compounds.

Activity of trout gill and soybean lipoxygenase was inhibited by various low concentrations of tri-n-butyltin, di-n-butyltin and n-butyltin chlorides at pH 7.8. Tri-n-butyltin (0.044-0.19 mM; 8-100% inhibition) was significantly more inhibitory against trout gill lipoxygenase than di-n-butyltin (0.1-0.27 mM; 17-39% inhibition) or n-butyltin (1.2-3.6 mM; 26-43% inhibition). Soybean lipoxygenase displayed a similar sensitivity to the inhibitory effects of organotin compounds at pH 7.8. Although tri-n-butyltin (0.067-0.2 mM; 13-68% inhibition) was less inhibitory to soybean lipoxygenase, di-n-butyltin (0.134-0.537 mM; 51-75% inhibition) and n-butyltin (0.41-1.23 mM; 33-75% inhibition) were more inhibitory towards soybean lipoxygenase compared with trout gill lipoxygenase. Concentrations of butyltins required to provide substantial inhibition of trout gill lipoxygenase were of the order of magnitude of those reported for lethal water exposure concentrations of these compounds for trout and other fishes when bioaccumulation factors are considered. Thus, it is proposed that inhibition of lipoxygenase likely contributes to the biocidal activity of organotin compounds.

Animals↗

A method for quantitative analysis of flavor-tainting alkylphenols and aromatic thiols in fish.

Simultaneous steam distillation-extraction (SDE) of fortified rainbow trout tissue resulted in greater than 95% recovery of 2-isopropylphenol, 3-isopropylphenol, 4-isopropylphenol, 2,4-diisopropylphenol, 2,5-diisopropylphenol, 3,5-diisopropylphenol, carvacrol and thymol. Lower recoveries were obtained for 2,6-diisopropylphenol (81%), thiophenol (55%), and thiocresol (85%). Analysis of concentrated extracts by gas chromatography/mass spectrometry operated in the selected ion monitoring mode allowed quantitative detection of these compounds down to 0.5 ppb based on 20 g of initial sample.

Animals↗

Volatile compounds in flavor-tainted fish from the Upper Wisconsin River.

Fillets from Walleye pike (Stizostedion vitreum) and Northern pike (Esox lucius) captured from the Upper Wisconsin River were analyzed for volatile components using simultaneous steam distillation-extraction and GC-MS techniques. Based on comparative odor assessments of eluting GC fractions and GC-MS analysis between control and tainted fish, trace amounts (ppb) of alkylphenols (2-isopropyl-, 4-isopropyl-, 2,4-diisopropyl-, 2,5-diisopropyl-, 2,6-diisopropyl-, 3,5-diisopropyl-, 5-methyl-2-isopropyl-, and 2-methyl-5-isopropyl-) and thiophenol were identified as the principal contributors to flavor-tainting found in fish during the spring of the year. Geosmin and 2-methylisoborneol were major contributors to mustiness flavor-tainting occurring in fish captured in the late summer and were more abundant in downstream fish than in upstream control fish.

Animals↗

Mercury residues in wood ducks and wood duck foods in eastern Tennessee.

Liver, breast muscle and body fat from 50 juvenile and five adult wood ducks (Aix sponsa) collected on the Holston River, Tennessee were analyzed for total mercury content. Black fly larvae (Simulium vittatum) sago pondweed (Potamogeton pectinatus), tapegrass (Vallisneria americanus), water stargrass (Heteranthera dubia), Elodea canadensis, and river bottom sediments were also analyzed to elucidate the distribution of mercury in the wood duck's environment. Liver tissues of juveniles contained the highest mean concentration of mercury (0.42 ppm). Mercury in breast muscle and body fat of juveniles averaged 0.15 and 0.10 ppm, respectively. Residues in corresponding tissues of adults were lower. Of environmental components tested, sediments had the highest mean concentration (0.76 ppm). Black fly larvae and aquatic plants had mean levels below 0.10 ppm.

Adipose Tissue↗

Effects of potassium sorbate and other antibotulinal agents on germination and outgrowth of Clostridium botulinum type E spores in microcultures.

The effects of potassium sorbate, sodium hypophosphite, sodium tripolyphosphate, sodium nitrite, and linoleic acid on the germination and outgrowth of Clostridium botulinum type E spores were studied in microcultures. At pH 5.8 to 6.0 in liver veal agar, the germination rate was decreased to nearly zero with 1.0, 1.5, or 2.0% sorbate. At pH 7.0 t 7.2, these levels of sorbate afforded germination and outgrowth of abnormally shaped cells that were defective in cell division. At the high pH range, 0.5 or 1.0% hypophosphite had effects similar to those of sorbate. The use of 0.05% sodium nitrite with sorbate enhanced the lysis of outgrowing cells at pH 7.2 or lower. Emergence and elongation were inhibited by 0.05% linoleic acid with or without 1.0% sorbate at pH 7.0 to 7.2. The addition of 0.5% tripolyphosphate to media containing 1.5% sorbate at pH 7.1 prevented normal cell growth to an extent greater than with sorbate alone.

Clostridium botulinum↗