Showing papers by "California State University, Long Beach published in 1996"

Brief interstadial events in the Santa Barbara basin, NE Pacific, during the past 60 kyr

Abstract: THE instability of the Northern Hemisphere glacial climate over the past 100 kyr has been revealed by at least 20 brief warm (interstadial) episodes, called Dansgaard–Oeschger events, recorded in Greenland ice cores1–3 and in North Atlantic sedimentary records4,5. A few of these events have been recognized elsewhere6–8. Here we describe a record of ocean oxygenation and circulation from the Santa Barbara basin in the northeast Pacific Ocean which correlates well with the Greenland ice-core records. We see 19 of the 20 Dansgaard–Oeschger events, in the form of laminated sediments deposited under anoxic conditions, and we can correlate at least 16 of these with the 17 ice-core interstadials of the past 60 kyr. Thus, these short-term events were not restricted to the North Atlantic region. The events had substantial ecological and oceanographic effects in the Santa Barbara basin, including changes in benthic faunal populations and in the age and composition of bottom waters. Similar ventilation changes have been seen in the Gulf of California9,10, suggesting that these changes may have been widespread and synchronous along the northeast Pacific margin. These results suggest sensitivity of broad areas of the ocean–atmosphere–cryosphere system to short-term climate change.

Clarifying the relationship between teacher nonverbal immediacy and student cognitive learning: Affective learning as the central causal mediator

Abstract: Recent research advanced a causal model explaining the teacher immediacy/student learning relationship by positing the mediational effects of students' state motivation to learn. This study argued instead for an alternative model which posits that affective learning, not state motivation, is the central causal mediator between teacher immediacy and students' cognitive learning. To test this causal model, students (N = 224) were asked to evaluate the instructors of their class meeting immediately after the course where they completed the questionnaires. These surveys included measures of teachers' nonverbal immediacy, students' state motivation to learn, and affective and cognitive learning. Path analytic tests of both models indicated that the Affective Learning Model provided the better theoretical explanation for the relationship between immediacy and cognitive learning.

A Re-Examination of Financial Analysts' Differential Earnings Forecast Accuracy

Abstract: This research re-examines whether there are differences in the forecast accuracy of financial analysts by comparing their annual earnings per share forecasts. The comparison of analyst forecast accuracy is made on both an ex post (within sample) and an ex ante (out of sample) basis. Early examinations of this issue by O'Brien (1990), Richards (1976), Brown and Rozeff (1980), O'Brien (1987), Coggin and Hunter (1989), Butler and Lang (1991) were ex post and suggest the absence of analysts who can provide relatively more accurate forecasts over multiple years. Contrary to the results of prior research, and consistent with the belief in the popular press, we document that differences do exist in financial analysts' ex post forecast accuracy. We show that the previous studies failed to find differences in forecast accuracy due to inadequate (or no) control for differences in the recency of forecasts issued by the analysts. It has been well documented in the literature that forecast recency is positively related to forecast accuracy (Crichfield, et al, 1978; O'Brien, 1988; Brown, 1991). Thus, failure to control for forecast recency may reduce the power of tests, making it difficult to reject the null hypothesis of no differences in forecast accuracy even if they do exist.

The Origin of Everyday Moods: Managing Energy, Tension, and Stress

Abstract: Part 1: Introduction Ch. 1. Mood and Its Meanings Ch. 2. A Theory of Mood Ch. 3. Moods as Barometers of General Condition Ch. 4. The Relationship Between Mood and Thoughts Ch. 5. Energy and Tension Changes with PMS, Drugs, Social Interaction, Weather, and Life Events Ch. 6. How Energy and Tension Interact Ch. 7. The Evolutionary Biology of Moods Ch. 8. The Physiology and Anatomy of Mood Part 2: The Self-regulation of Mood Ch. 9. Self-regulation: Why, How, and How Effective? Ch. 10. Individual Differences in Mood-regulating Strategies Ch. 11. Mood Substitution: Different Ways of Getting the Same Mood Ch. 12. Rational Mood Substitution: Exercise More and Indulge Less Part 3: Optimal Mood Management Ch. 13. The Practical Psychology of Self-Regulation Ch. 14. Overcoming Tense-tiredness Through Energy Enhancement Ch. 15. Reducing Tension to Overcome Tense-Tiredness Ch. 16. Moods at Different Times of Day Ch. 17. Systematic Self-observation: The First Step in Mood Change Ch. 18. The Origin and Self-regulation of Everyday Moods: A Review Appendix. Beyond Stress Management to Calm-energy Notes Index

A lower limit of 9.5 Gyr on the age of the Galactic disk from the oldest white dwarf stars

Abstract: WHITE dwarf stars represent the final evolutionary state for most main-sequence stars. They cool slowly enough that even the oldest white dwarfs are still observable in sufficiently deep surveys and they therefore provide a record of the age and star-formation history of the local disk of the Milky Way1–7—and hence a useful constraint on the age of the Galaxy itself. Here we report the initial results of a very deep survey of white dwarfs, that avoids many of the problems associated with the incompleteness of earlier surveys. We use model age–luminosity relations to interpret the luminosity function of our sample of stars, and thus obtain a minimum age for the local Galactic disk of ∼9.5 Gyr. Our results lend weight to an emerging picture of the evolutionary history of the Milky Way, in which the halo formed ∼14–17 Gyr ago8,9, followed by the bulge globular clusters ∼12–14 Gyr ago10, with a modest hiatus before the onset of star formation in the local disk ∼10 Gyr ago.

English-Only and Standard English Ideologies in the U.S.

Abstract: planning and policy from a historical-structural perspective by analyzing and synthesizing a broad base of literature. It compares and contrasts two popularly accepted ideologies. The first is the ideology of English monolingualism, which frames policy issues in an immigrant paradigm in order to portray language diversity as an alien and divisive force; the second involves a standard language ideology that is used to position speakers of different varieties of the same language within a social hierarchy. The article discusses the connection between assumptions underlying linguistic ideologies and other social ideologies related to individualism and social mobility through education. It discusses limitations in the immigrant paradigm and considers the instrumental role that schools play in positioning students by using language assessment and classification schemes. Dilemmas and opportunities for contesting these ideologies are addressed. Dominant attitudes toward language in the U.S. are replete with contradictions. Bilingualism, for example, has tended to be seen as either a curse or a blessing. This contradiction is evident in the contrast between two drastically different policies toward bilingualism. The first is a policy toward language minority students that is intended to prescribe rapid transition out of LI instruction into English-only instructionoften resulting in the eventual loss of the L1. The second is a policy toward monolingual English-speaking students that is intended to promote learning a foreign language. In terms of resource allocation, bilingual programs are mandated to develop languages other than English-only to a minimum level-whereas foreign language programs spend millions attempting to develop them further (see Crawford, 1992a; Simon, 1988). However, on closer inspection, the root of this contradiction becomes clear: These policies are designed for two different populations. Transitional bilingual education, developed under

Sperm motility development in the epididymis is associated with decreased glycogen synthase kinase-3 and protein phosphatase 1 activity.

Abstract: Immotile bovine caput epididymal sperm contain levels of protein phosphatase activity twofold higher than do mature motile caudal sperm. Comparison of the inhibition profiles of endogenous phosphatase activities detected by okadaic acid (OA) and calyculin A (CA) revealed a pattern consistent with the predominance of a type 1 protein phosphatase (PP1). Immunoblot analysis identified PP1 gamma 2 (the testis-specific isoform of PP1) as the only PP1 isoform in sperm and showed little protein phosphatase 2A (PP2A). In addition, of the known PP1 inhibitors, i.e., DARPP-32, inhibitor 1 (I1), and inhibitor 2 (I2), only I2-like activity was detected in sperm. Inhibition of PP1 by the heat-stable I2-like activity purified from sperm could be reversed with purified glycogen synthase kinase-3 (GSK-3). Furthermore, sperm extracts contain an inactive complex of PP1 and I2 (termed PP1I) that could also be activated by purified GSK-3. The presence of GSK-3 in sperm was demonstrated by activation of purified PP1I, and quantitation revealed that immotile caput sperm contained sixfold higher GSK-3 activity than motile caudal sperm. Immunoblot analysis confirmed the expression of GSK-3 in sperm and revealed the occurrence of both the alpha and beta isoforms. Our findings suggest that the higher PP1 activity measured in immotile sperm, presumably due to higher GSK-3 activity, is responsible for holding motility in check. This conclusion was supported by the observation that the phosphatase inhibitors OA and CA, at micromolar and nanomolar levels, respectively, were able to induce motility in completely immotile bovine caput epididymal sperm and to stimulate the kinetic activity of mature caudal sperm. The intrasperm levels of cAMP, pH, and calcium were unaltered by treatment with these inhibitors. The results suggest a biochemical basis for the development and regulation of sperm motility and a possible physiological role for the PP1/I2/GSK-3 system.

Fluid-Attenuated Inversion Recovery (FLAIR) for Assessment of Cerebral Infarction Initial Clinical Experience in 50 Patients

Abstract: Background and Purpose Our aim was to evaluate fluid-attenuated inversion recovery (FLAIR) sequence in the diagnosis of cerebral infarction with MRI. Methods A retrospective review was undertaken of 50 consecutive MRI studies ordered for suspected cerebrovascular accident. All studies included FLAIR and rapid acquisition with relaxation enhancement (RARE) T2-weighted spin-echo sequences. The two sequences were compared independently by four observers at two different institutions. Detectability of lesions and image quality were scored. Results Overall, FLAIR sequences proved superior in 10 patients, detecting acute cortical infarcts missed with RARE spin-echo technique in five patients. In five additional patients, improved characterization of chronic infarction and improved detection of microangiopathic deep hemispheric changes were observed. One brain stem infarct was missed with the FLAIR sequence. Conclusions FLAIR offers advantages in detection of acute infarcts affecting the cortical ribbon, is a us...

Active parental consent in school-based research. An examination of ethical and methodological issues.

Abstract: To date, most school-based research has used passive parental consent. However, the Family Privacy Protection Act of 1995 aims to change these requirements. The proposed legislation requires written parental consent if minors are to be asked "sensitive" questions as part of any program or activity funded in whole or in part by the federal government. This act is representative of a growing trend toward restricting research involving minors. Whether or not this act is passed by Congress, two lines of concern are highlighted by this legislation. The first deals with ethical issues surrounding consent procedures. For instance, are parental rights compromised when active consent is not mandated? A second line of inquiry pertains to the effect of active consent procedures on response rates and sample bias. In this article, the authors discuss ethical issues surrounding passive and active consent procedures and then report response rates from two projects in which active consent procedures were implemented.

Sources of Perceived Organizational Support: Goal Setting and Feedback1

Abstract: In this paper we examine goal setting and feedback as possible sources of perceived organizational support (Eisenberger, Huntington, Hutchison, & Sowa, 1986). Surveys were administered to 337 employees from 3 different organizations in the southern California area. Two path models were examined: one that allowed goal setting and feedback to have direct effects on perceived support and organizational commitment, and one that only allowed goal setting and feedback to have direct effects on perceived support. Results show that goal setting and feedback do not have direct effects on organizational commitment but, rather, affect commitment indirectly by way of their effects on employee perceptions of support from the organization.

Simulation of the formation of nonequilibrium structures in magnetorheological fluids subject to an external magnetic field.

Abstract: We developed a computer model to understand the nonequilibrium structures induced in a magnetorheological (MR) fluid by rapidly applying an external magnetic field MR fluids consist of particles suspended in a liquid where particles interact through dipole moments induced by the external magnetic field We have simulated these induced structures in both directions, parallel and perpendicular to the field, in the limit of fastest response, by neglecting thermal motion and applying the field instantaneously Our results show that the process of structure formation starts with particles forming chains aligned with the external field The chains then coalesce to form columns and wall-like structures (``worms'' as viewed from the top) The complexity of this pattern is found to depend on the concentration of particles and the confinement of the cell in the direction of the external field These results are consistent with experimental observations [GA Flores et al, in Proceedings of the Fifth International Conference on ER Fluids, MR Suspensions, and Associate Technology, University of Sheffield, Sheffield, 1995, edited by W Bullough (World Scientific, Singapore, 1996), p 140] We have also used this model to study the interaction of two chains The results of this study help in the understanding of the connection between the thickness of the sample and the increased complexity of the observed lateral pattern \textcopyright{} 1996 The American Physical Society

Failure of Anterior Cruciate Ligament Reconstruction: The Biologic Basis

Abstract: The replacement tissue used for anterior cruciate ligament reconstruction undergoes extensive biologic remodeling and incorporation after implantation. Successful biologic incorporation of the graft is dependent on a number of factors including graft placement, tensioning, and the nature of the tissue (allograft versus autograft). Failure of an anterior cruciate ligament reconstruction may occur on the basis of either technical, mechanical, or biological factors. Biologic factors include cellular repopulation, matrix remodeling, the ultimate small diameter collagen fibril orientation, the final cross sectional area of the graft, a favorable vascularization, and not overloading the graft during the remodeling process. The fully incorporated graft never duplicates the native anterior cruciate ligament but works as a check reign that makes the knee more functional.

Rheology of a Magnetorheological Fluid

Abstract: We report on experimental investigations of the rheological behavior of aqueous magnetic suspensions. The suspended particles are monodisperse colloidal polystyrene spheres which contain magnetic Fe203-grains. In the absence of a magnetic field these suspensions behave as Newtonian fluids, whereas under the influence of a magnetic field due to the formation of an ordered structure the apparent viscosity of the suspension increases up to three orders of magnitude and they clearly exhibit non-Newtonian properties, such as shear thinning and yield stress. The apparent viscosity depends on the magnetic field according to aq - H2". Increasing the volume fraction of the particles in the range of 0.014 < 0 < 0.12 results in a linear increase in apparent viscosity and yield stress. Both apparent viscosity and yield stress depend also on the particle size as first measurements on particles with diameters ranging from 0.5 Am to 1.0,Am clearly show. All measurements were carried out with a rotation viscometer using ...

Using the Theory of Planned Behavior to Predict Intention to Use Condoms Among Male and Female Injecting Drug Users

Abstract: The utility of the theory of planned behavior for predicting condom use intentions was demonstrated in a study of 405 male and 315 US intravenous drug users. According to this theory behavior is a direct function of intentions in turn a function of attitudes toward the behavior and perceptions of relevant social norms. The variables in the model explained 36-48% of condom use intention; social norm was the only variable of no salience to any of the analyses. Attitude toward condom use was strongly associated with condom use intentions regardless of gender or type of partner. In addition intention to use condoms with ones main partner was positively and significantly correlated for men with partner norm and for women with partner norm and perceived behavioral control. Intention to use condoms with a casual partner was significantly associated for men and women with attitude and perceived behavioral control but not social or partner norms. Women were significantly more likely than men to perceive themselves as at risk of contracting human immunodeficiency virus from a non-principal partner. The beliefs that using condoms is a responsible thing to do and can reduce worrying were significantly associated with attitudes toward condom use with both principal and non-principal partners among men but only for principal partners among women. For women condom use was most likely in the context of a relatively stable relationship characterized by some intimacy. The lack of impact of social norms on condom use intentions is assumed to reflect the alienation from the social mainstream of intravenous drug abusers. Given the importance of the attitudinal variable however interventions that focus on creating more positive views toward condom use among drug users seem indicated.

Revisiting the Dimensions of Acculturation: Cultural Theory and Psychometric Practice:

Abstract: Although acculturation has frequently been employed as an organizing principle in social science research, there remains a lack of clarity regarding "the dimensions of acculturation. " The confusio...

A Comparison of MRI and Clinical Examination of Acute Lateral Ankle Sprains

Abstract: Because of its excellent soft tissue contrast and ability to demonstrate soft tissue structures, magnetic resonance imaging is ideally suited to the evaluation of the soft tissues surrounding the ankle, including the lateral collateral ligaments. This study was undertaken to compare the clinical evaluation of 15 patients who suffered inversion injuries of the ankle with the results found on magnetic resonance imaging within 48 hours of the injury. Physical examination was found to be 100% accurate in the diagnosis of grade III ligament injuries but only 25% accurate in the diagnosis of grade II injuries. Clinicians most often underestimate the damage with a grade II ligament tear. Furthermore, other associated injuries, such as significant capsule ruptures and tendon damage, were often overlooked at physical examination.

Helping Children Tell What Happened: A Follow-Up Study of the Narrative Elaboration Procedure

Abstract: In cases of child maltreatment, children are required to recount past experiences in pretrial interviews, courtroom examination, and abuse-focused therapy. Yet their descriptions are often insufficient for risk assessment, legal decision making, and treatment planning. In the present study, we test whether a new procedure—narrative elaboration—facilitates children's recall without jeopardizing accuracy. Thirty-three second graders participated in a classroom activity. Two weeks later, they were randomly assigned to participate in one of two preparation sessions before being interviewed about the classroom activity: (a) narrative elaboration intervention or (b) control session. The interviewer was an unfamiliar authority figure. The interview entailed free recall (e.g., “What happened?”), cued recall (i.e., an opportunity to elaborate on free recall with visual cues), and follow-up questions. On the cued recall task, children prepared with the narrative elaboration procedure reported significantly more cor...

Biologic Remodeling after Anterior Cruciate Ligament Reconstruction Using a Collagen Matrix Derived from Demineralized Bone An Experimental Study in the Goat Model

Abstract: A matrix of demineralized cortical bone was used to reconstruct the anterior cruciate ligament in the goat model. This graft underwent considerable site-specific remodeling and transformation from a Haversian system at time zero into a ligament-like structure at 1 year. This transformation included new bone formation filling the osseous tunnels and replacing the demineralized matrix, development of a ligament-like transition zone within the graft, and ligamentous collagen orientation with crimp in the intraarticular portion of the graft. One year after surgery, the mean anterior-posterior translation in the reconstructed stifle joints at 30 N of tibial loading was 2.1 +/- 0.4 (+/- SEM). The mean ultimate force to failure for the reconstructed ligament at 1 year was 474 +/- 146 N compared with the time-zero (initial) strength of the matrix of 73 +/- 9 N. The cellular repopulation of the graft had no associated inflammatory cells. The potential clinical significance of these findings includes 1) replacement of a collagen matrix with bone within the osseous tunnels, 2) establishment of a more physiologic fibrocartilage transition at the graft insertion site, 3) the time-zero structural properties of a collagen matrix increasing to more desired values with biologic remodeling, and 4) a sterile biologic allograft with essentially no long-term inflammatory response.

Method for preparing pre-coated aluminum alloy articles and articles prepared thereby

Abstract: An aluminum-alloy article such as a fastener is prepared by providing an aluminum-alloy article precursor that is not in its final heat-treated state, and in one form is in its solution treated/annealed state. A curable organic coating material is also provided. The method includes anodizing the article precursor, preferably in chromic acid solution and without chemical sealing during anodizing, applying the organic coating material to the aluminum-alloy article precursor, and precipitation heat-treating the coated aluminum article precursor to its final heat-treated state, thereby simultaneously curing the organic coating. If the aluminum alloy temper is of the naturally aging type, it is optionally lightly deformed prior to precipitation treatment aging. The approach may also be applied to articles that are not solution treated/annealed and aged, by first overly deforming the article precursor so that the curing treatment of the coating also partially anneals the article precursor to the final desired deformation state.

A double-blind trial of low- and high-dose ranges of gepirone-er compared with placebo in the treatment of depressed outpatients

Abstract: We report the results of a double-blind study comparing the efficacy and safety of low-dose (10-50 mg) and high-dose (20-100 mg) ranges of gepirone-extended release (ER) and placebo in 145 outpatients with major depressive disorder. At multiple time points and endpoint (Week 6), statistically significant reductions in Hamilton Rating Scale for Depression (HAM-D) scores were recorded for high-dose gepirone-ER compared to placebo. Analysis of the 17-item HAM-D and 28-item HAM-D scores indicated a relatively early onset of antidepressant efficacy with statistically significant results at treatment Weeks 1, 2, 4, and 6. A rapid response was evident in the high-dose group, beginning at Week 1 (p < .05). The most frequently reported adverse experiences were headache, nausea, dizziness, and insomnia. The results indicate that gepirone-ER is clearly superior to placebo in terms of antidepressant efficacy. When used at higher doses, gepirone-ER appears to be efficacious, safe, and well-tolerated in depressed out-patients.

Effects of process parameters on the properties of squeeze-cast SiCp-6061 Al metal-matrix composite

Abstract: The effects of process parameters on the properties of squeeze-cast high reinforcement volume-fraction SiCp-6061 Al metal matrix composite (MMC) have been examined. The process parameters included cooling rate, reinforcement particle size, addition of silica binder, and solution treatment temperature. The properties studied were flexure strength, microstructure, variation of hardness, solute content gradient, and aging behavior. It was found that water cooling improved the flexure strength and hardness of MMC significantly when compared with furnace-cooled MMC. For the same volume fraction of reinforcement, lowering the average particle size from 85 to 14 μm increased the flexure strength and hardness of the MMC greatly. A solution treatment temperature very close to the eutectic point was found to improve the strength. Mechanisms leading to the above-mentioned effects and suggestions are discussed.

Power driven tools

Abstract: According to one embodiment, a power driven socket wrench is disclosed to rotate nuts and bolts in confined spaces including a head formed of a rotatable socket for engaging nuts and bolts, a bearing for the rotatable socket and a housing around the socket and bearing. The socket has a plurality of gear teeth thereon extending around its axis. An important feature of the invention is the provision of a drive adapter between the head and a power drive for driving the socket. The adapter is detachable from the head and the power drive for replacement by an adapter of a different length to enable reaching a nut or bolt at a more remote distance. The adapter has an outer elongate housing containing an elongate drive shaft mounted axially therein on suitable bearings. The adapter housing and shaft are positioned for rotation of the shaft on an axis extending perpendicular to the rotational axis of the socket on the head. A rotatable input gear is mounted on the inner end of the shaft and meshes with the gear teeth around the socket for driving same. The adapter has a detachable locking means such as a snap lock at its inner end for detachably locking the adapter onto the housing of the head. The outer end of the adapter drive shaft has a detachable locking member for detachably engaging the driver member of a power drive or motor.