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Showing papers by "University of New Mexico published in 1991"


Journal ArticleDOI
TL;DR: Individual differences in willingness to engage in uncommitted sexual relations were investigated in 6 studies and it was demonstrated that the SOI correlates negligibly with measures of sexual satisfaction, anxiety, and guilt.
Abstract: Individual differences in willingness to engage in uncommitted sexual relations were investigated in 6 studies. In Study 1, a 5-item Sociosexual Orientation Inventory (SOI) was developed. Studies 2, 3, and 4 provided convergent validity evidence for the SOI, revealing that persons who have an unrestricted sociosexual orientation tend to (a) engage in sex at an earlier point in their relationships, (b) engage in sex with more than 1 partner at a time, and (c) be involved in relationships characterized by less investment, commitment, love, and dependency. Study 5 provided discriminant validity for the SOI, revealing that it does not covary appreciably with a good marker of sex drive. Study 6 demonstrated that the SOI correlates negligibly with measures of sexual satisfaction, anxiety, and guilt. The possible stability of, origins of, and motivational bases underlying individual differences in sociosexuality are discussed.

1,283 citations


Book
01 Jan 1991
TL;DR: Neamen's Semiconductor Physics and Devices, Third Edition as discussed by the authors deals with the electrical properties and characteristics of semiconductor materials and devices, and brings together quantum mechanics, the quantum theory of solids, semiconductor material physics, and semiconductor device physics in a clear and understandable way.
Abstract: Neamen's Semiconductor Physics and Devices, Third Edition. deals with the electrical properties and characteristics of semiconductor materials and devices. The goal of this book is to bring together quantum mechanics, the quantum theory of solids, semiconductor material physics, and semiconductor device physics in a clear and understandable way. Table of contents Prologue Semiconductor and the Integrated Circuit 1 The Crystal Structure of Solids 2 Introduction to Quantum Mechanics 3 Introduction to the Quantum Theory of Solids 4 The Semiconductor in Equilibrium 5 Carrier Transport Phenomena 6 Nonequilibrium Excess Carriers in Semiconductors 7 The pn Junction 8 The pn Junction Diode 9 Metal-Semiconductor and Semiconductor Heterojunctions 10 The Bipolar Transistor 11 Fundamentals of the Metal-Oxide-Semiconductor Field-Effect Transistor 12 Metal-Oxide-Semiconductor Field-Effect Transistor: Additional Concepts 13 The Junction Field-Effect Transistor 14 Optical Devices 15 Semiconductor Power Devices Appendix A Selected List of Symbols Appendix B System of Units, Conversion Factors, and General Constants Appendix C The Periodic TableAppendix D The Error FunctionAppendix E "Derivation" of Schrodinger's Wave EquationAppendix F Unit of Energy- The Electron-VoltAppendix G Answers to Selected Problems

837 citations


Journal ArticleDOI
01 May 1991-Nature
TL;DR: In this paper, a new detector for atom interferometers, constructed with the aid of modern quantum optics, provides a way around the obstacle of position-momentum uncertainty relation and allows the investigation of other mechanisms that enforce complementarity.
Abstract: Simultaneous observation of wave and particle behaviour is prohibited, usually by the position–momentum uncertainty relation New detectors, constructed with the aid of modern quantum optics, provide a way around this obstacle in atom interferometers, and allow the investigation of other mechanisms that enforce complementarity

763 citations


Journal ArticleDOI
TL;DR: A large second-order nonlinearity is induced in the near-surface region of commercial fused-silica optical flats by a temperature and electric-field poling process and is extremely stable at room temperature and laboratory ambient.
Abstract: A large second-order nonlinearity [ χ(2)~1 pm/V~0.2 χ22(2) for LiNbO3] is induced in the near-surface (~4 μm) region of commercial fused-silica optical flats by a temperature (250–325°C) and electric-field (E ~ 5 × 104 V/cm) poling process. Once formed, the nonlinearity, which is roughly 103–104 times larger than that found in fiber second-harmonic experiments, is extremely stable at room temperature and laboratory ambient. The nonlinearity can be cycled by repeated depoling (temperature only) and repoling (temperature and electric field) processes without history effects. Possible mechanisms, including nonlinear moieties and electric-field-induced second-order nonlinearities, are discussed.

746 citations


Journal ArticleDOI
TL;DR: The authors examine output time series from seven different public bureaucracies for responsiveness to political tools applied in the late Carter and early Reagan administrations and find responsiveness in all seven cases, indicating that political appointments are the most important instrument of political control; changing budgets, legislation, congressional signals, and administrative reorganizations are less important.
Abstract: A new paradigm of political-bureaucratic relations emerged through the 1980s holding that U.S. democratic institutions continuously shape nonelective public bureaucracies. Several empirical studies support the paradigm with evidence suggestive of political manipulation but none reveals the scope or specific mechanisms of political control. We explore the dynamics of political control of the bureaucracy explicitly to determine the scope and mechanisms. We examine output time series from seven different public bureaucracies for responsiveness to political tools applied in the late Carter and early Reagan administrations. We find responsiveness in all seven cases. The evidence also shows that political appointments—a shared power of the president and Congress—is the most important instrument of political control; changing budgets, legislation, congressional signals, and administrative reorganizations are less important. These findings confirm intuitive assertions by institutional scholars and suggest a method of “policy monitoring” that could enhance future democratic control of the bureaucracy.

634 citations


Journal ArticleDOI
TL;DR: Atoms prepared in a coherent superposition of a ground- (or excited-) state doublet can produce a large resonant index of refraction with vanishing absorption.
Abstract: Atoms prepared in a coherent superposition of a ground- (or excited-) state doublet can produce a large resonant index of refraction with vanishing absorption.

608 citations


Journal ArticleDOI
TL;DR: The reviewed observations suggest that a variety of initiatives are warranted to alter the time children spend watching television, the content of programs, and the types of programs for children and adolescents that are produced and broadcast.

500 citations


Journal ArticleDOI
TL;DR: The data presented here suggests that myelopathic patients with a cervical kyphosis are best treated with an ACDF and that Patients with a normal cervical lordosis arebest treated with a posterior approach.
Abstract: Seventy-five patients who underwent surgical treatment for cervical spondylotic myelopathy were evaluated with respect to the operative procedure performed and their outcome. Forty patients underwent a laminectomy plus dentate ligament section (DLS), 18 underwent laminectomy alone, and 17 underwent an anterior cervical decompression and fusion (ACDF). The patients were evaluated postoperatively for both stability and for neurologic outcome using a modification of the Japanese Orthopaedic Association Assessment Scale. Functional improvement occurred in all but one patient in the laminectomy plus DLS group. The average improvement was 3.1 +/- 1.5 points in this group; whereas the average improvement in the laminectomy and the ACDF groups was 2.7 +/- 2.0 and 3.0 +/- 2.0 points respectively. All of the patients who improved substantially (greater than or equal to 6 points) in the laminectomy plus DLS and the laminectomy alone groups had normal cervical spine contours (lordosis). The remainder had either a normal lordosis or no curve (no kyphosis or lordosis). All patients in the ACDF group had either a straight spine or a cervical kyphosis. These factors implicate spine curvature, in addition to choice of operation, as factors which are important in outcome determination. No problems with instability occurred in either the laminectomy or the laminectomy plus DLS group. Two patients incurred problems with stability in the ACDF group. Both required reoperation. In addition, four patients in this group who initially improved, subsequently deteriorated. Six patients in the laminectomy plus DLS group had a several day febrile episode related to an aseptic meningitis process. Laminectomy plus DLS is a safe and efficacious alternative to laminectomy for the treatment of cervical spondylotic myelopathy. The data presented here suggests that myelopathic patients with a cervical kyphosis are best treated with an ACDF and that patients with a normal cervical lordosis are best treated with a posterior approach. Although some selected patients may benefit from DLS, no criteria are available which differentiate this small subset of patients.

424 citations


Journal ArticleDOI
TL;DR: The authors examined the effects of economic crisis on electoral outcomes in Latin America from 1982 to 1990 and found that crisis conditions undermine support for incumbents and provoke high levels of electoral volatility but without necessarily fostering the growth of political extremism or the exhaustion of elite consensus associated with the breakdown of democracy.
Abstract: Research on the political implications of economic conditions is separated into two relatively distinct bodies of literature. I bridge the theoretical gap between them by examining the effects of economic crisis on electoral outcomes in Latin America from 1982 to 1990. An analysis of 21 competitive elections indicates that crisis conditions undermine support for incumbents and provoke high levels of electoral volatility but without necessarily fostering the growth of political extremism or the exhaustion of elite consensus associated with the breakdown of democracy. The results also suggest that the relationship between economic conditions and electoral instability is mediated by party system structure rather than democratic age. Paradoxically, the findings buttress prior research on electoral outcomes in the comparatively stable and homogeneous Organization for Economic Cooperation and Development (OECD) nations while undercutting theoretical frameworks elaborated with specific reference to the breakdown and consolidation of Third World democracy.

408 citations


Journal ArticleDOI
TL;DR: In this paper, a survey of the robust control of the motion of rigid robots is presented, including linear-multivariable approach, passivity approach, variable-structure approach, saturation approach, and robust-adaptive approach.
Abstract: Current approaches to the robust control of the motion of rigid robots are surveyed, and the available literature is summarized. The five major design approaches discussed are the linear-multivariable approach, the passivity approach, the variable-structure approach, the saturation approach, and the robust-adaptive approach. Some guidelines for choosing a method are offered. >

391 citations


Journal ArticleDOI
TL;DR: It is suggested that transesophageal echocardiography is highly sensitive and specific for the diagnosis of infective endocarditis and significantly more sensitive than transthoracic echOCardiography.

Journal ArticleDOI
TL;DR: In this paper, a local, nonlinear transform is derived that allows an STM or AFM image which has been distorted by a nonideal tip to be reconstructed, where the image reconstruction transform is related to the Legendre transforms of the distorted image surface and the tip surface.

Journal ArticleDOI
TL;DR: Fentanyl and sufentanil have similar pharmacodynamic profiles, the former being 12 times more potent than the latter, according to the electroencephalogram.
Abstract: The authors compared the pharmacodynamics of sufentanil with those of fentanyl using the electroencephalogram (EEG) as a measure of opioid drug effect. Sixteen patients were given a rapid infusion of sufentanil (18.75 micrograms/min) during EEG recording. To quantitate the opioid-induced slowing of the EEG, the authors analyzed its power spectrum and calculated the spectral edge. An inhibitory sigmoid Emax model of the maximal decrease in spectral edge produced by the opioid related spectral edge values to serum concentrations of sufentanil. The resulting data for the pharmacodynamic parameters of sufentanil were compared with fentanyl parameters that were obtained by reanalysis from an identically conducted, previously published study. The half-time of blood-brain equilibration (T1/2Keo) was not statistically different between sufentanil and fentanyl (6.2 +/- 2.8 vs. 6.6 +/- 1.7 min, mean +/- SD, respectively). The intrinsic potency of sufentanil, as measured by the serum concentration needed to cause half the maximal EEG slowing (IC50), was 12-fold greater (0.68 +/- 0.31 ng/ml) than that of fentanyl (8.1 +/- 2.2 ng/ml). The second part of the study verified the hypothesis that administration of equipotent bolus doses would produce equal onset times. Bolus injections of either 125 micrograms of sufentanil or 1,250 micrograms of fentanyl were given during EEG recording. The time from injection to 50% maximal EEG slowing (T50) was calculated for each patient. The values for T50 for the two groups did not differ. The authors conclude that fentanyl and sufentanil have similar pharmacodynamic profiles, the former being 12 times more potent than the latter.

Journal ArticleDOI
TL;DR: Topical masoprocol appears to be useful in the treatment of actinic keratoses andIrritation, as manifested by erythema or flaking, occurred in 61.5% of topical masop rocol-treated patients versus 26.7% of those treated with vehicle and did not correlate with clinical response.
Abstract: This double-blind, vehicle-controlled, multicenter study evaluated the efficacy and safety of a new topical antineoplastic agent, masoprocol, in the treatment of actinic keratoses of the head and neck. Of the 113 patients who applied topical masoprocol twice a day for 14 to 28 days, there was a mean decrease in actinic keratoses from 15.0 to 5.4 and a median percent reduction from baseline actinic keratosis count of 71.4% at the 1-month follow-up visit. Comparable numbers for the vehicle-treated group were 13.4 to 11.1 actinic keratoses and 4.3% median percent reduction. Irritation, as manifested by erythema or flaking, occurred in 61.5% of topical masoprocol-treated patients versus 26.7% of those treated with vehicle and did not correlate with clinical response. Topical masoprocol appears to be useful in the treatment of actinic keratoses.

Journal ArticleDOI
11 Dec 1991-JAMA
TL;DR: Old Joe Camel cartoon advertisements are far more successful at marketing Camel cigarettes to children than to adults, consistent with tobacco industry documents that indicate that a major function of tobacco advertising is to promote and maintain tobacco addiction among children.
Abstract: Objectives. —To determine if RJR Nabisco's cartoon-theme advertising is more effective in promoting Camel cigarettes to children or to adults. To determine if children see, remember, and are influenced by cigarette advertising. Design. —Use of four standard marketing measures to compare the effects of Camel's Old Joe cartoon advertising on children and adults. Subjects. —High school students, grades 9 through 12, from five regions of the United States, and adults, aged 21 years and over, from Massachusetts. Outcome Measures. —Recognition of Camel's Old Joe cartoon character, product and brand name recall, brand preference, appeal of advertising themes. Results. —Children were more likely to report prior exposure to the Old Joe cartoon character (97.7% vs 72.2%;P Conclusion. —Old Joe Camel cartoon advertisements are far more successful at marketing Camel cigarettes to children than to adults. This finding is consistent with tobacco industry documents that indicate that a major function of tobacco advertising is to promote and maintain tobacco addiction among children. (JAMA1991;266:3149-3153)

Journal ArticleDOI
TL;DR: A similar pattern of results was found: the proportions of irrelevant thoughts and recall performance were -negatively related, and happy and sad students produced reliably greater proportions of relevant thoughts than did neutral (control) students.
Abstract: In two experiments, we investigated the relationship shared by irrelevant thoughts, emotional mood states, and cognitive task performance. At an empirical level, irrelevant thoughts were defined as thoughts that did not facilitatesuccessful task performance. We used the same general procedure for both experiments: three groups of college students received happy-, neutral- (control), or sad-mood inductions and performed a memory task. The procedure for obtaining thoughts varied between experiments. The subjects in Experiment 1 listed their thoughts after the memory recall task. In Experiment 2, the subjects were tape-recorded while performing a memory task and producing concurrent verbal protocols. The subjects in both experiments then judged their thoughts in terms of frequency, intensity,and irrelevance. Wefound a similar pattern of results in both experiments: (1) The proportions ofirrelevant thoughts and recall performance were -negatively related, and (2) happy and sad studentsproduced reliably greater proportions of irrelevant thoughts than did neutral (control) students.

Journal ArticleDOI
01 Feb 1991-Genetics
TL;DR: A chi-square test used to detect heterogeneity of admixture estimates from different alleles, or loci, can now be corrected for both sources of random errors, and its value for the detection of natural selection from heterogeneous admixtures estimates is improved.
Abstract: A method for simultaneously estimating the admixture proportions of a hybrid population and Wright's fixation index, FST, for that hybrid is presented. It is shown that the variance of admixture estimates can be partitioned into two components: (1) due to sample size, and (2) due to evolutionary variance (i.e., genetic drift). A chi-square test used to detect heterogeneity of admixture estimates from different alleles, or loci, can now be corrected for both sources of random errors. Hence, its value for the detection of natural selection from heterogeneous admixture estimates is improved. The estimation and testing procedures described above are independent of the dynamics of the admixture process. However, when the admixture dynamics can be specified, FST can be predicted from genetic principles. Two admixture models are considered here, gene flow and intermixture. These models are of value because they lead to very different predictions regarding the accumulation of genes from the parental populations and the accumulation of variance due to genetic drift. When there is not evidence for natural selection, and it is appropriate to apply these models to data, the variance effective size (Ne) of the hybrid population can be estimated. Applications are made to three human populations: two of these are Afro-American populations and one is a Yanomamo Indian village. Natural selection could not be detected using the chi-square test in any of these populations. However, estimates of effective population sizes do lead to a richer description of the genetic structure of these populations.

Journal ArticleDOI
TL;DR: Patients treated with a single broad-spectrum antibiotic had a better outcome than patients treated with multiple drug treatment and inadequate empiric antibiotic treatment was associated with poorer outcome than any other type of treatment.
Abstract: The charts of 480 patients with secondary bacterial peritonitis were reviewed. The antibiotics used were compared with the culture and sensitivity data obtained at surgery, and the outcomes of patients were evaluated. Patients treated with a single broad-spectrum antibiotic had a better outcome than patients treated with multiple drug treatment. Inadequate empiric antibiotic treatment was associated with poorer outcome than any other type of treatment. The outcome of this inadequate treatment group could not be improved by any antibiotic response to culture and sensitivity information after operation. Those patients treated with antibiotic coverage for anticipated organisms and having no cultures taken did as well as patients having cultures taken. Surgeons typically ignore culture data after operation, and only 8.8% of patients in this study had an appropriate change in antibiotic treatment after operation. A benefit from obtaining operative cultures could not be identified.

Journal ArticleDOI
TL;DR: This work examines the role of high-density lipoprotein, cholesterol lowering drugs, and intracellular lipid transfer proteins in membrane sterol domain structure and sterol movement between membranes to elucidation of cholesterol dynamics in membranes.
Abstract: Nonreceptor mediated cholesterol uptake and reverse cholesterol transport in cells occur through cellular membranes. Thus, elucidation of cholesterol dynamics in membranes is essential to understanding cellular cholesterol accumulation and loss. To this end, it has become increasingly evident that cholesterol is not randomly distributed in either model or biologic membranes. Instead, membrane cholesterol appears to be organized into structural and kinetic domains or pools. Cholesterol-rich and poor domains can even be observed histochemically and physically isolated from epithelial cell surface membranes. The physiologic importance of these domains is 2-fold: (i) Select membrane proteins (receptors, transporters, etc.) are localized in either cholesterol-rich or cholesterol-poor domains. Consequently, the structure and properties of the domains rather than of the bulk lipid may selectively affect the function of proteins residing therein. (ii) Kinetic evidence suggests that cholesterol transport through and between membranes may occur through specific domains or pools. Regulation of the size and properties of such domains may be controlling factors of cholesterol transport or accumulation in cells. Recent technologic advances in the use of fluorescent sterols have allowed examination of cholesterol domain structure in model and biologic membranes. These techniques have been applied to examine the role of high-density lipoprotein, cholesterol lowering drugs, and intracellular lipid transfer proteins in membrane sterol domain structure and sterol movement between membranes.

Journal ArticleDOI
TL;DR: The quantum-mechanical superposition of two coherent states of identical mean photon number but different phases yields a state that can exhibit sub-Poissonian and oscillatory photon statistics, as well as squeezing.
Abstract: The quantum-mechanical superposition of two coherent states of identical mean photon number but different phases yields a state that can exhibit sub-Poissonian and oscillatory photon statistics, as well as squeezing.

Journal ArticleDOI
TL;DR: In this article, the authors developed a behavioral framework to predict how venture capital managers will behave in choosing between various investment opportunities in order to minimize risk and to maximize potential returns, based on the psychological risk theory of decision-making under uncertainty.

Journal ArticleDOI
TL;DR: In this article, the reduction of cores and retouched tools in eight Mousterian assemblages from west-central Italy reflects the effects of several processes and contingencies, including raw material accessibility, differential transport, patterns of site use, and tool function.

Journal ArticleDOI
TL;DR: An elevated risk of breast cancer was found for any job with exposure, and risk was highest among electricians, telephone linemen, and electric power workers and radio and communications workers.
Abstract: Data from a population-based case-control study of breast cancer in men were used to examine the hypothesis that occupational exposure to electromagnetic fields increases the risk of breast cancer. Incident cases (n = 227) diagnosed between 1983 and 1987 were obtained from 10 population-based cancer registries of the Surveillance, Epidemiology, and End Results program of the National Cancer Institute. Controls (n = 300) were selected by random digit dialing and from Medicare eligibility lists. Exposure status, defined as ever having been employed in a job which has been classified as involving potential exposure to electromagnetic fields, was assigned without knowledge of case/control status. An elevated risk was found for any job with exposure (odds ratio (OR) = 1.8, 95 percent confidence interval (CI) 1.0-3.7), and risk was highest among electricians, telephone linemen, and electric power workers (OR = 6.0, 95 percent CI 1.7-21) and radio and communications workers (OR = 2.9, 95 percent CI 0.8-10). Risk did not vary with duration of exposed employment. The risk was highest among subjects who were first employed in jobs with exposure before the age of 30 years and who were initially exposed at least 30 years prior to diagnosis. These results lend support to the theory that electromagnetic fields may be related to breast cancer in men. The hypothesis warrants evaluation in women.

Journal ArticleDOI
01 Jun 1991-Chest
TL;DR: The dental orthosis is an effective treatment for the symptom of snoring and can also effectively treat obstructive sleep apnea of moderate severity and can be associated with higher initial frequencies of apneas and hypopneas.

Journal ArticleDOI
TL;DR: The study demonstrates significant niche separation between Middle and Upper Paleolithic hominids in Mediterranean Europe and demonstrates strong links between predator strategies, assemblage size and anatomical content, and some spatial characteristics of food supply.

Journal ArticleDOI
TL;DR: Hypothesis tests for homogeneity of matrices and equal-variance/equal-covariance indicate that the intrinsic variation in nasal breadth is greater than that for nasal height within populations, and that nasal breadth and nasal height exhibit equivalent intrinsic variation among populations, which support, but do not demonstrate, an adaptive role for human nasal index variation.
Abstract: It has been suggested that the long-standing association of variability in the human nasal index [100 × (nasal breadth)/(nasal height)] with climatic variation is spurious evidence for natural selection in humans (Hoyme, 1965; St. Hoyme and Iscan, 1989). The argument is based principally on the observation that nasal height is globally more variable than nasal breadth, with nasal breadth thus contributing little to variation in the index. This argument does not take into account the confounding effect of absolute size of these variables on their variances. In this study we compare the intrinsic variation in skeletal nasal height and breadth within and among 26 mixed-sex populations (N = 2,408) at globally diverse localities (Howells, 1989), using 2 × 2 variance-covariance matrices of the logarithmically transformed variates. Hypothesis tests for homogeneity of matrices and equalvariance/equal-covariance indicate that the intrinsic variation in nasal breadth is greater than that for nasal height within populations, and that nasal breadth and nasal height exhibit equivalent intrinsic variation among populations. The argument that nasal breadth contributes little to the worldwide variation in the human nasal index is rejected. Given our present understanding of nasal physiological morpho-function, these results support, but do not demonstrate, an adaptive role for human nasal index variation. Promising methods for elucidating natural selection on human nasal form are suggested.

Journal ArticleDOI
TL;DR: The envelope gene of the avian hepadnavirus, duck hepatitis B virus, was mutated in order to dissect the functions of the two major envelope proteins pre-S/S and S, found to be required for virus particle assembly and secretion.
Abstract: The envelope gene of the avian hepadnavirus, duck hepatitis B virus, was mutated in order to dissect the functions of the two major envelope proteins pre-S/S and S. Both envelope proteins were found to be required for virus particle assembly and secretion. The placement of stop codons after each of the first three AUG codons in the pre-S region allowed efficient translational initiation at downstream AUG codons to produce novel N-terminally truncated pre-S/S proteins. These proteins could substitute for pre-S/S protein in the production of enveloped virus production, but not in the production infectious virus. A mutant defective in myristylation of the pre-S/S protein produced reduced amounts of enveloped virus, and this virus was not infectious. Mutants defective in the pre-S/S protein accumulated high levels of covalently closed circular viral DNA (cccDNA) compared with the wild type or with a mutant defective in only the S protein. Hyperamplification of cccDNA resulted in high levels of viral RNA, consistent with the proposed role of cccDNA as the transcriptional template. Myristylation of the pre-S/S protein was not required for control of cccDNA amplification, and mutants that produced N-terminally truncated pre-S/S proteins displayed higher levels of cccDNA. We concluded that the pre-S/S protein, but not the S protein, is required for control of cccDNA amplification and persistent infection.

Journal ArticleDOI
01 Feb 1991-Brain
TL;DR: Central programming deficits in Parkinson's disease (PD) were studied in two reaction time (RT) experiments and PD patients' decision times improved more with a longer delay only for heterogeneous sequences, suggesting a problem in identifying the number of different hand postures.
Abstract: Central programming deficits in Parkinson's disease (PD) were studied in two reaction time (RT) experiments. In Experiment 1, PD patients and controls performed sequences of hand postures that varied in length, the number of different postures (repetitive vs heterogeneous), and the delay interval before movement. Before movement, the PD group planned repetitive movements like controls whereas for heterogeneous sequences RT increased less with sequence length for the PD group, implying less preprogramming. The interresponse time (IRT) data from repetitive sequences showed that the PD group had difficulty controlling movement such that IRTs were faster when sequences were longer, thus allowing more time to schedule the termination of the sequence during the course of movement. For heterogeneous sequences, the PD group made more errors and were slower than controls when changing hand postures, suggesting a deficit in switching between different responses. While RT decreased with a longer delay similarly for both groups, IRT1 continued to improve only for the PD group but similarly for both types of sequences, suggesting a deficit specific to programming the first response. In Experiment 2, subjects made decisions about the number of different hand postures contained within a sequence. PD patients' decision times improved more with a longer delay only for heterogeneous sequences, suggesting a problem in identifying the number of different hand postures. The results have implications for levels of motor dysfunction in PD which emphasize the influence of sequence length and complexity.

Journal ArticleDOI
TL;DR: In this article, the authors explore the two most critical factors that influence an organization's willingness to participate: its stakes in solving the problem relative to its fundamental interests, and its degree of perceived interdependence with other groups in devising a solution.
Abstract: Cross-sectoral collaboration to address social problems is becoming more widespread. To assess the potential for the formation of cross-sectoral collaborations, this article explores the two most critical factors that influence an organization's willingness to participate: its stakes in solving the problem relative to its fundamental interests, and its degree of perceived interdependence with other groups in devising a solution. Two patterns of evolution toward collaborative formation are identified: movement from interdependence to interests, and movement from interests to interdependence. These patterns are illustrated by two case studies about successful cross-sectoral collaborations, one to improve a regional transportation system and one to create the first comprehensive regulations for underground chemical storage tanks.

Journal ArticleDOI
20 Dec 1991-Science
TL;DR: The observation of negative regulation of the immunoglobulin heavy chain gene enhancer by an element similar to NRE-A suggests that related proteins may regulate multiple immune response genes.
Abstract: Transient activation of the interleukin-2 (IL-2) gene after antigen recognition by T lymphocytes is crucial for subsequent T cell proliferation and differentiation. Several IL-2 gene regulatory elements and binding factors necessary for activation of the IL-2 gene have been defined. However, little is known about negative regulation of IL-2 expression, which is likely to be important in the rapid shut-off of IL-2 transcription. A nucleotide sequence element (NRE-A) that negatively regulates IL-2 expression has been identified within the IL-2 gene. T cell nuclear extracts contained an NRE-A binding activity. A complementary DNA was isolated that encodes a zinc finger-containing protein that suppressed IL-2 gene expression. The observation of negative regulation of the immunoglobulin heavy chain gene enhancer by an element similar to NRE-A suggests that related proteins may regulate multiple immune response genes.