Stimulus context effects, associative strength, and word frequency as determiners of free recall in paired-associate learning.

Two levels of response word frequency and three levels of associative strength of paired-associates were used to form six lists. One level of low associative strength between pairs to be learned was created by re-pairing stimuli and responses from high associative strength lists. Both the high associative strength condition and the re-paired condition produced superior recall of response items. Results suggested that the development of response availability in paired-associate learning depends in part not only upon the strength of the initial relationship between each stimulus and response pair to be learned, but also upon the context provided by other stimuli in the list. The meaning of "present at input" in studies evaluating the principle of encoding specificity (Tulving & Thompson, 1973) was questioned. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relationship between student personality characteristics, teacher ratings, and student achievement.

In Study 1, 388 undergraduates (a) rated themselves on the Adjective Check List (ACL), (b) viewed a videotape that varied in instructor expressiveness and lecture content, (c) evaluated the videotaped instructor and a test on the lecture, and (d) completed the ACL for the instructor. In Study 2, 87 Ss were also exposed to 2 videotaped lectures given 1 wk apart. In Study 3, 108 Ss completed the ACL for themselves and their instructors, evaluated their instructor's teaching, and completed a test on common course material. No meaningful or consistent relationship between ratings and student personality characteristics appeared to exist. Personality characteristics of instructors were related to teacher effectiveness ratings. Ratings predicted teacher-produced achievement equally well for classes that differed in the personality characteristics of the students enrolled. Teacher effects on ratings appeared significantly greater than teacher effects on achievement. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of the Minnesota Multiphasic Personality Inventory and Mini-Mult with drug users.

Data from 60 male drug addicts and users support previous findings that when correlations between corresponding MMPI and Mini-Mult scales are used, there is good correspondence; however, there is low accuracy with respect to clinical evaluation and high-point correspondence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Research in the community cauldron: A case history.

This paper considers a series of natural hazards that community researchers must face, including: being a "foreign body" to the system under examination; the time-consuming, longitudinal demands of studies in this area; the dangers of program instability and change; the need for community accountability; and the pro-action, anti-research orientation of many community program personnel. These hazards lead to riskier studies and to research that falls short of traditional standards of scientific rigor. However, unless investigators are willing to gamble with less precise, less well controlled approaches, and to build knowledge through gross successive approximations, many significant, exciting problems of community psychology will not be studied. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Corrections for restriction of range and attenuation in criterion-related validation studies.

The results of 1,253 Navy enlisted personnel on the Navy Basic Test Battery and the Navy Enlisted Advancement Exam were used as predictor and criterion, respectively. Groups were selected according to 5 selection ratios, .10 to .50. Results were then compared to the true validity. Except for the selection ratio of .10, all of the corrected validity coefficients slightly over-estimated the true validity. Triple and 2-step correction procedures yielded equivalent results. In all cases, the corrected coefficients better estimated the unrestricted true validity. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The reduction of sulfide minerals by hydrogen in the presence of lime

Calcium oxide favors greatly the reduction of metal sulfides by H₂ at 800°C. Copper sulfides and copper-iron sulfides are reduced rapidly to metals: Cu₂S+H₂+CaO→2Cu+CaS+H₂O CuS+H₂+CaO→Cu+CaS+H₂O Cu₅FeS₄+4H₂+4CaO→5Cu+ Fe+4CaS+4H₂O The reduction of chalcopyrite takes place according to any of the following reactions depending on the amount of CaO added: Cu₂S·Fe₂S₃+H₂+CaO→Cu₂S·2FeS+CaS+H₂O Cu₂S·Fe₂S₃+3H₂+3CaO→Cu₂S+2Fe+3CaS+3H₂O Cu₂S·Fe₂S₃+4H₂+4CaO→2Cu+2Fe+4CaS+4H₂O Gravity and magnetic methods were not successful in separating the reaction products. However, leaching by dilute HCl was successful in eliminating CaS and iron (as FeS as well as metal) leaving behind Cu₂S concentrate or metallic copper, respectively. Reduction of molybdenite is also influenced by the presence of CaO, but that of pentlandite is not. FATHI HABASHI and RAYMOND DUGADALE, formerly with the Research Division of the Anaconda Company, Tucson, Arizona     

Premorbid social competence construct generalizability across ethnic groups: Path analyses with two premorbid social competence components.

Studied the stability across ethnic groups of interrelations among 5 variables (education, age at 1st psychiatric hospitalization, current age, alcoholism symptom severity, and behavioral adjustment while hospitalized) using path analysis. 24 male Mexican Americans, mean age 39.8 yrs, and 24 male Anglo Americans, mean age 47.1 yrs, were studied. Behavioral adjustment was determined with the MACC Behavioral Adjustment Scale. Certain findings involving 4 variables were consistent with theoretical expectations for the Anglo-American group but were reversed in the Mexican-American group. Methodological and theoretical implications are presented. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship of temperature to composition of copolymers of α-methylstyrene and maleic anhydride

Alternating copolymers of α-methylstyrene and maleic anhydride were prepared in good yields in a decalin solution at temperatures below 80°C. Random copolymers with large percentages of α-methylstyrene were obtained in good yields at higher temperatures. These results were in accord with the charge transfer complex which was characterized by n.m.r. and u.v. spectrophotometry and shown to exist below 80°C. The copolymers were characterized by pyrolysis/gas chromatography and differential scanning calorimetry. The glass transition temperature of poly(α-methylstyrene) and the random copolymer of this monomer and maleic anhydride were approximately 450 and 458 K respectively.     

Metallographic features associated with the penetration of titanium alloy targets

Ballistic tests on Ti-6A1-4V alloy targets have produced a number of interesting features. There was direct evidence of melting at the projectile-target interface. The targets failed by adiabatic shear and evidence for cavity growth in the shear bands is presented. Observed directionality in the ballistic performance of the target material is associated with anisotropy of the target material.