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Showing papers by "University of Iowa published in 1997"


Journal ArticleDOI
20 Nov 1997-Nature
TL;DR: It is demonstrated that it is possible to retain information about only four colours or orientations in visual working memory at one time, but it is also possible to retaining both the colour and the orientation of four objects, indicating that visual workingMemory stores integrated objects rather than individual features.
Abstract: Short-term memory storage can be divided into separate subsystems for verbal information and visual information, and recent studies have begun to delineate the neural substrates of these working-memory systems. Although the verbal storage system has been well characterized, the storage capacity of visual working memory has not yet been established for simple, suprathreshold features or for conjunctions of features. Here we demonstrate that it is possible to retain information about only four colours or orientations in visual working memory at one time. However, it is also possible to retain both the colour and the orientation of four objects, indicating that visual working memory stores integrated objects rather than individual features. Indeed, objects defined by a conjunction of four features can be retained in working memory just as well as single-feature objects, allowing sixteen individual features to be retained when distributed across four objects. Thus, the capacity of visual working memory must be understood in terms of integrated objects rather than individual features, which places significant constraints on cognitive and neurobiological models of the temporary storage of visual information.

3,608 citations


Journal ArticleDOI
28 Feb 1997-Science
TL;DR: The results suggest that, in normal individuals, nonconscious biases guide behavior before conscious knowledge does, and without the help of such biases, overt knowledge may be insufficient to ensure advantageous behavior.
Abstract: Deciding advantageously in a complex situation is thought to require overt reasoning on declarative knowledge, namely, on facts pertaining to premises, options for action, and outcomes of actions that embody the pertinent previous experience. An alternative possibility was investigated: that overt reasoning is preceded by a nonconscious biasing step that uses neural systems other than those that support declarative knowledge. Normal participants and patients with prefrontal damage and decision-making defects performed a gambling task in which behavioral, psychophysiological, and self-account measures were obtained in parallel. Normals began to choose advantageously before they realized which strategy worked best, whereas prefrontal patients continued to choose disadvantageously even after they knew the correct strategy. Moreover, normals began to generate anticipatory skin conductance responses (SCRs) whenever they pondered a choice that turned out to be risky, before they knew explicitly that it was a risky choice, whereas patients never developed anticipatory SCRs, although some eventually realized which choices were risky. The results suggest that, in normal individuals, nonconscious biases guide behavior before conscious knowledge does. Without the help of such biases, overt knowledge may be insufficient to ensure advantageous behavior.

3,265 citations


Journal ArticleDOI
24 Apr 1997-Nature
TL;DR: Using positron emission tomographic images of cerebral blood flow and rate of glucose metabolism to measure brain activity, an area of abnormally decreased activity is localized in the pre-frontal cortex ventral to the genu of the corpus callosum in both familial bipolar depressives and familial unipolar depressives.
Abstract: Pathological disturbances of mood may follow a 'bipolar' course, in which normal moods alternate with both depression and mania, or a 'unipolar' course, in which only depression occurs. Both bipolar and unipolar disorders can be heritable illnesses associated with neurochemical, neuroendocrine and autonomic abnormalities. The neurobiological basis for these abnormalities has not been established. Using positron emission tomographic (PET) images of cerebral blood flow and rate of glucose metabolism to measure brain activity, we have now localized an area of abnormally decreased activity in the prefrontal cortex ventral to the genu of the corpus callosum in both familial bipolar depressives and familial unipolar depressives. This decrement in activity was at least partly explained by a corresponding reduction in cortical volume, as magnetic resonance imaging (MRI) demonstrated reductions in the mean grey matter volume in the same area of 39 and 48% in the bipolar and unipolar samples, respectively. This region has previously been implicated in the mediation of emotional and autonomic responses to socially significant or provocative stimuli, and in the modulation of the neurotransmitter systems targeted by antidepressant drugs.

2,575 citations


Journal ArticleDOI
TL;DR: The prevalence estimates obtained fell within recent estimates for SLI, but demonstrated that this condition is more prevalent among females than has been previously reported.
Abstract: This epidemiologic study estimated the prevalence of specific language impairment (SLI) in monolingual English-speaking kindergarten children. From a stratified cluster sample in rural, urban, and ...

1,932 citations


Book
28 Jun 1997
TL;DR: In this paper, a brief discussion of integral equations is given, and the Nystrom method is used to solve multivariable integral equations on a piecewise smooth planar boundary.
Abstract: Preface 1. A brief discussion of integral equations 2. Degenerate kernel methods 3. Projection methods 4. The Nystrom method 5. Solving multivariable integral equations 6. Iteration methods 7. Boundary integral equations on a smooth planar boundary 8. Boundary integral equations on a piecewise smooth planar boundary 9. Boundary integral equations in three dimensions Discussion of the literature Appendix Bibliography Index.

1,719 citations


Journal ArticleDOI
TL;DR: The role of attention was examined in areas V1, V2, and V4 of macaque monkeys with the use of a behavioral paradigm in which attention was directed to one of two stimulus locations and it was found that the cell's response was strongly influenced by which of the two stimuli was attended.
Abstract: Luck, Steven J., Leonardo Chelazzi, Steven A. Hillyard, and Robert Desimone. Neural mechanisms of spatial selective attention in areas V1, V2, and V4 of macaque visual cortex. J. Neurophysiol. 77: ...

1,492 citations


Journal ArticleDOI
Marc S. Wold1
TL;DR: Replication protein A (RPA) is a single-stranded DNA-binding protein that is required for multiple processes in eukaryotic DNA metabolism, including DNA replication, DNA repair, and recombination.
Abstract: Replication protein A [RPA; also known as replication factor A (RFA) and human single-stranded DNA-binding protein] is a single-stranded DNA-binding protein that is required for multiple processes in eukaryotic DNA metabolism, including DNA replication, DNA repair, and recombination. RPA homologues have been identified in all eukaryotic organisms examined and are all abundant heterotrimeric proteins composed of subunits of approximately 70, 30, and 14 kDa. Members of this family bind nonspecifically to single-stranded DNA and interact with and/or modify the activities of multiple proteins. In cells, RPA is phosphorylated by DNA-dependent protein kinase when RPA is bound to single-stranded DNA (during S phase and after DNA damage). Phosphorylation of RPA may play a role in coordinating DNA metabolism in the cell. RPA may also have a role in modulating gene expression.

1,454 citations


Journal ArticleDOI
31 Jan 1997-Science
TL;DR: A gene encoding a trabecular meshwork protein (TIGR) mapped to the narrowest disease interval by STS content and radiation hybrid mapping and will aid in early diagnosis of glaucoma.
Abstract: Glaucoma is a major cause of blindness and is characterized by progressive degeneration of the optic nerve and is usually associated with elevated intraocular pressure. Analyses of sequence tagged site (STS) content and haplotype sharing between families affected with chromosome 1q-linked open angle glaucoma (GLC1A) were used to prioritize candidate genes for mutation screening. A gene encoding a trabecular meshwork protein (TIGR) mapped to the narrowest disease interval by STS content and radiation hybrid mapping. Thirteen glaucoma patients were found to have one of three mutations in this gene (3.9 percent of the population studied). One of these mutations was also found in a control individual (0.2 percent). Identification of these mutations will aid in early diagnosis, which is essential for optimal application of existing therapies.

1,401 citations


Journal ArticleDOI
TL;DR: This article found that the operating performance of issuing firms shows substantial improvement prior to the offering, but then deteriorates following a sharp run-up in the year prior to an offering, and that the multiples at the time of the offering do not reflect an expectation of deteriorating performance.
Abstract: Recent studies have documented that firms conducting seasoned equity offerings have inordinately low stock returns during the five years after the offering, following a sharp run-up in the year prior to the offering. This article documents that the operating performance of issuing firms shows substantial improvement prior to the offering, but then deteriorates. The multiples at the time of the offering, however, do not reflect an expectation of deteriorating performance. Issuing firms are disproportionately high-growth firms, but issuers have much lower subsequent stock returns than nonissuers with the same growth rate. SEVERAL RECENT EMPIRICAL STUDIES have documented the poor stock market performance of firms conducting seasoned equity offerings (SEOs) in the United States and other countries.1 Loughran and Ritter (1995) report that the average raw return for issuing firms is only 7 percent per year during the five years after the offering, compared to 15 percent per year for nonissuing firms of the same market capitalization. These low postissue returns follow extremely high returns in the year prior to the offering: 72 percent on average.2 This article links the stock price performance of these issuing firms to their operating performance, and in so doing, addresses four questions: 1) Does the postissue operating performance of issuers deteriorate relative to comparable nonissuing firms? 2) Are the patterns for large issuers different from those for small issuers? 3) Do the capital expenditure decisions of issuers suggest that the managers are just as overoptimistic as investors are? 4) Given that issuing firms tend to be rapidly growing, and rapidly growing firms display strong

1,107 citations


Journal ArticleDOI
TL;DR: CpG ODN provide a signal to switch on Th1-dominated responses to coadministered antigen and are potential adjuvants for human vaccines to elicit protective Th1 immunity.
Abstract: Synthetic oligodeoxynucleotides (ODN) that contain unmethylated CpG motifs (CpG ODN) induce macrophages to secrete IL-12, which induces interferon (IFN)-γ secretion by natural killer (NK) cells. Since these cytokines can induce T helper 1 (Th1) differentiation, we examined the effects of coadministered CpG ODN on the differentiation of Th responses to hen egg lysozyme (HEL). In both BALB/c (Th2-biased) and B10.D2 (Th1-biased) mice, immunization with HEL in incomplete Freund's adjuvant (IFA) resulted in Th2-dominated immune responses characterized by HEL-specific secretion of IL-5 but not IFN-γ. In contrast, immunization with IFA-HEL plus CpG ODN switched the immune response to a Th1-dominated cytokine pattern, with high levels of HEL-specific IFN-γ secretion and decreased HEL-specific IL-5 production. IFA-HEL plus CpG ODN also induced anti-HEL IgG2a (a Th1-associated isotype), which was not induced by IFA-HEL alone. Control non–CpG ODN did not induce IFN-γ or IgG2a, excepting lesser increases in B10.D2 (Th1-biased) mice. Thus, CpG ODN provide a signal to switch on Th1-dominated responses to coadministered antigen and are potential adjuvants for human vaccines to elicit protective Th1 immunity.

1,100 citations


Journal ArticleDOI
TL;DR: This review represents an update of the nomenclature system for the UDP glucuronosyltransferase gene superfamily, which is based on divergent evolution and is anticipated that this UGT gene nomenClature system will require updating on a regular basis.
Abstract: This review represents an update of the nomenclature system for the UDP glucuronosyltransferase gene superfamily, which is based on divergent evolution. Since the previous review in 1991, sequences of many related UDP glycosyltransferases from lower organisms have appeared in the database, which expand our database considerably. At latest count, in animals, yeast, plants and bacteria there are 110 distinct cDNAs/genes whose protein products all contain a characteristic 'signature sequence' and, thus, are regarded as members of the same superfamily. Comparison of a relatedness tree of proteins leads to the definition of 33 families. It should be emphasized that at least six cloned UDP-GlcNAc N-acetylglucosaminyltransferases are not sufficiently homologous to be included as members of this superfamily and may represent an example of convergent evolution. For naming each gene, it is recommended that the root symbol UGT for human (Ugt for mouse and Drosophila), denoting 'UDP glycosyltransferase,' be followed by an Arabic number representing the family, a letter designating the subfamily, and an Arabic numeral denoting the individual gene within the family or subfamily, e.g. 'human UGT2B4' and 'mouse Ugt2b5'. We recommend the name 'UDP glycosyltransferase' because many of the proteins do not preferentially use UDP glucuronic acid, or their nucleotide sugar preference is unknown. Whereas the gene is italicized, the corresponding cDNA, transcript, protein and enzyme activity should be written with upper-case letters and without italics, e.g. 'human or mouse UGT1A1.' The UGT1 gene (spanning > 500 kb) contains at least 12 promoters/first exons, which can be spliced and joined with common exons 2 through 5, leading to different N-terminal halves but identical C-terminal halves of the gene products; in this scheme each first exon is regarded as a distinct gene (e.g. UGT1A1, UGT1A2, ... UGT1A12). When an orthologous gene between species cannot be identified with certainty, as occurs in the UGT2B subfamily, sequential naming of the genes is being carried out chronologically as they become characterized. We suggest that the Human Gene Nomenclature Guidelines (http://www.gene.acl.ac.uk/nomenclature/guidelines.html++ +) be used for all species other than the mouse and Drosophila. Thirty published human UGT1A1 mutant alleles responsible for clinical hyperbilirubinemias are listed herein, and given numbers following an asterisk (e.g. UGT1A1*30) consistent with the Human Gene Nomenclature Guidelines. It is anticipated that this UGT gene nomenclature system will require updating on a regular basis.

Journal ArticleDOI
TL;DR: Heparin, highly sulfated heparan sulfate, and the polysulfonate pharmaceutical Suramin effectively prevented dengue virus infection of target cells, indicating that the envelope protein-target cell receptor interaction is a critical determinant of infectivity.
Abstract: Dengue virus is a human pathogen that has reemerged as an increasingly important public health threat. We found that the cellular receptor utilized by dengue envelope protein to bind to target cells is a highly sulfated type of heparan sulfate. Heparin, highly sulfated heparan sulfate, and the polysulfonate pharmaceutical Suramin effectively prevented dengue virus infection of target cells, indicating that the envelope protein-target cell receptor interaction is a critical determinant of infectivity. The dengue envelope protein sequence includes two putative glycosaminoglycan-binding motifs at the carboxy terminus; the first could be structurally modeled and formed an unusual extended binding surface of basic amino acids. Similar motifs were also identified in the envelope proteins of other flaviviridae. Developing pharmaceuticals that inhibit target cell binding may be an effective strategy for treating flavivirus infections.

Journal ArticleDOI
TL;DR: It is demonstrated that leptin increases thermogenic sympathetic nerve activity and reveal an unexpected stimulatory effect of leptin on overall sympathetic nerve traffic.
Abstract: Leptin is a peptide hormone produced by adipose tissue which acts centrally to decrease appetite and increase energy expenditure. Although leptin increases norepinephrine turnover in thermogenic tissues, the effects of leptin on directly measured sympathetic nerve activity to thermogenic and other tissues are not known. We examined the effects of intravenous leptin and vehicle on sympathetic nerve activity to brown adipose tissue, kidney, hindlimb, and adrenal gland in anesthetized Sprague-Dawley rats. Intravenous infusion of mouse leptin over 3 h (total dose 10-1,000 microg/kg) increased plasma concentrations of immunoreactive murine leptin up to 50-fold. Leptin slowly increased sympathetic nerve activity to brown adipose tissue (+286+/-64% at 1,000 microg/kg; P = 0.002). Surprisingly, leptin infusion also produced gradual increases in renal sympathetic nerve activity (+228+/-63% at 1,000 microg/kg; P = 0.0008).The effect of leptin on sympathetic nerve activity was dose dependent, with a threshold dose of 100 microg/kg. Leptin also increased sympathetic nerve activity to the hindlimb (+287+/-60%) and adrenal gland (388+/-171%). Despite the increase in overall sympathetic nerve activity, leptin did not increase arterial pressure or heart rate. Leptin did not change plasma glucose and insulin concentrations. Infusion of vehicle did not alter sympathetic nerve activity. Obese Zucker rats, known to possess a mutation in the gene for the leptin receptor, were resistant to the sympathoexcitatory effects of leptin, despite higher achieved plasma leptin concentrations. These data demonstrate that leptin increases thermogenic sympathetic nerve activity and reveal an unexpected stimulatory effect of leptin on overall sympathetic nerve traffic.

Book ChapterDOI
01 Jan 1997
TL;DR: The theoretical views of extraversion have gradually but systematically evolved over the past 75 years as mentioned in this paper, and it now appears that extraversion essentially taps individual differences in affectively rewarding performance.
Abstract: Publisher Summary This chapter focuses on the theoretical views of extraversion. Extraversion has been included as a higher-order factor in every major taxonomic scheme of personality traits that have been developed during the past 50 years. Extraversion consistently emerges as a higher-order disposition in taxonomic schemes of personality traits. Higher-order traits represent the most general level in the hierarchy of dispositions. This is the level at which personologists attempt to explain individual differences with the fewest possible and most broadly applicable dimensions. Extraversion is divided into two distinct subfactors: (1) it involves successful adaptation through satisfying interpersonal relationships, and (2) another that entails adaptation through dominance, mastery, and achievement. Theoretical conceptualizations of extraversion have gradually but, systematically evolved over the past 75 years. This evolution necessarily involves elements of both continuity and change. The continuity is largely reflected in the interpersonal components of the trait. Recent conceptualizations have also stressed the positive affective component of the trait. These models emphasize that extraverts are happy, enthusiastic, confident, active, and energetic. More fundamentally, it now appears that extraversion essentially taps individual differences in affectively rewarding performance. Compared to introverts, extraverts view themselves as more effectively and pleasurably engaged in various aspects of their lives.

BookDOI
Yinyu Ye1
TL;DR: This paper presents a meta-analyses of Linear Programming Algorithms and its applications to Convex Optimization, focusing on the areas of linear programming and nonconvex optimization.
Abstract: Geometry of Convex Inequalities. Computation of Analytic Center. Linear Programming Algorithms. Worst-Case Analysis. Average-Case Analysis. Asymptotic Analysis. Convex Optimization. Nonconvex Optimization. Implementation Issues. Bibliography. Index.

Journal ArticleDOI
TL;DR: This paper examined the dispositional basis of job seekers' organizational culture preferences and how these preferences interact with recruiting organizations' cultures in their relation to organization attraction, and found that both objective person-organization fit and subjective fit mediated the relationship between objective fit and organization attraction.
Abstract: This study examined the dispositional basis of job seekers' organizational culture preferences and how these preferences interact with recruiting organizations' cultures in their relation to organization attraction. Data were collected from 182 business, engineering, and industrial relations students who were seeking positions at the time of the study. Results obtained from multiple sources suggested that the Big Five personality traits (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness) generally were related to hypothesized dimensions of culture preferences. Results also suggested that both objective person-organization fit (congruence between applicant culture preferences and recruiting organization's reputed culture) and subjective fit (applicant's direct perception of fit) were related to organization attraction. Further, subjective fit mediated the relationship between objective fit and organization attraction.

Journal ArticleDOI
TL;DR: In this article, a theoretical and experimental investigation of a two-dimensional chiral honeycomb was conducted, and the honeycomb exhibits a Poisson's ratio of 1 for deformations in plane.

Journal ArticleDOI
Joseph Piven1, Pat Palmer1, Dinah Jacobi1, Debra Childress1, Stephan Arndt1 
TL;DR: Higher rates of social and communication deficits and stereotyped behaviors were found in the relatives in the families with multiple-incidence autism, suggesting that this broader autism phenotype should be included in some future genetic analyses of this disorder.
Abstract: Objective: Studies of families ascertained through a single autistic proband suggest that the genetic liability for autism may be expressed in nonautistic relatives in a phenotype that is milder but qualitatively similar to the defining features of autism. The objective of this study was to examine behaviors that may define this broader phenotype in relatives ascertained through two autistic siblings. Method: The authors used a semistructured family history interview to compare the rates of social and communication deficits and stereotyped behaviors in relatives ascertained through two autistic siblings (families with multiple-incidence autism; 25 families) with the rates in relatives of Down syndrome probands (30 families). Results: Higher rates of social and communication deficits and stereotyped behaviors were found in the relatives in the families with multiple-incidence autism. Conclusions: These data suggest that further studies should be undertaken to delineate the boundaries of the broader autism phenotype and that this broader phenotype should be included in some future genetic analyses of this disorder. (Am J Psychiatry 1997; 154:185‐190)

Journal ArticleDOI
TL;DR: The view that adult articular cartilage is an inert bearing surface, like high-density polyethylene or metal, and that degeneration of the articular surface with age is the result of mechanical wear with inevitable, irreversible loss of structure and mechanical performance resulting from joint use is supported.
Abstract: Joint pain and loss of mobility are among the most common causes of impairment in middle-aged and older people36,134. In many instances, the degeneration of articular cartilage and alterations in other joint tissues that result from the loss of structure and function of articular cartilage cause the pain and the loss of motion28,46,47,85,118,150. This occurs most frequently in the clinical syndrome of idiopathic or primary osteoarthrosis, but it may also result from joint injury or from developmental, metabolic, and inflammatory disorders that destroy the articular surface, causing secondary osteoarthrosis28,46,118. An understanding of the degeneration of articular cartilage, osteoarthrosis, and the potential for restoring an articular surface depends to a large extent on an appreciation of the biological behavior and the responsiveness of articular cartilage to injury and disease. Of considerable importance is the observation, first reported centuries ago and confirmed by multiple investigators over the last fifty years, that adult articular cartilage does not have the capacity to repair structural damage resulting from injury or disease29,32,71. This observation has contributed to the view that adult articular cartilage is an inert bearing surface, like high-density polyethylene or metal, and that degeneration of the articular surface with age is the result of mechanical wear with inevitable, irreversible loss of structure and mechanical performance resulting from joint use62. The implication of this view is that, other than limiting joint use or loading, little or nothing can be done to prevent the degeneration of articular cartilage, and the most appropriate treatment for advanced degeneration of cartilage leading to the clinical syndrome of osteoarthrosis is replacement of the articular surface. Alternatively, if articular cartilage is …

Journal ArticleDOI
TL;DR: The cloning of the small subunit of Drosophila P-TEFb and the finding that it encodes a Cdc2-related protein kinase is reported, indicating that P- TEFb is a Tat-associated kinase (TAK) and PITALRE associated with the activation domain of HIV-1 Tat.
Abstract: P-TEFb is a key regulator of the process controlling the processivity of RNA polymerase II and possesses a kinase activity that can phosphorylate the carboxy-terminal domain of the largest subunit of RNA polymerase II. Here we report the cloning of the small subunit of Drosophila P-TEFb and the finding that it encodes a Cdc2-related protein kinase. Sequence comparison suggests that a protein with 72% identity, PITALRE, could be the human homolog of the Drosophila protein. Functional homology was suggested by transcriptional analysis of an RNA polymerase II promoter with HeLa nuclear extract depleted of PITALRE. Because the depleted extract lost the ability to produce long DRB-sensitive transcripts and this loss was reversed by the addition of purified Drosophila P-TEFb, we propose that PITALRE is a component of human P-TEFb. In addition, we found that PITALRE associated with the activation domain of HIV-1 Tat, indicating that P-TEFb is a Tat-associated kinase (TAK). An in vitro transcription assay demonstrates that the effect of Tat on transcription elongation requires P-TEFb and suggests that the enhancement of transcriptional processivity by Tat is attributable to enhanced function of P-TEFb on the HIV-1 LTR.

Journal ArticleDOI
TL;DR: It is shown that Positive and Negative Affect scales remain largely independent across a wide range of conditions, even after controlling for random and systematic error.
Abstract: The affective explosion in psychology has led to tremendous advances in mood measurement. Mood ratings reflect a hierarchical structure consisting of two broad dimensions-Positive Affect and Negative Affect-and multiple specific states. Brief scales have been developed that reliably assess Positive and Negative Affect across different populations and time frames, in both between- and within-subject data. We examine controversies related to (a) the content of these higher order scales and (b) the independence of Positive and Negative Affect. Regarding the latter, we show that Positive and Negative Affect scales remain largely independent across a wide range of conditions, even after controlling for random and systematic error. Finally, there remains little consensus regarding the lower order structure of affect. This lack of a compelling taxonomy has substantially slowed progress in assessing mood at the specific affect level.

Journal ArticleDOI
07 Feb 1997-Science
TL;DR: Results suggest that Ad vector-mediated GDNF gene therapy may slow the DA neuronal cell loss in humans with Parkinson's disease.
Abstract: Glial cell line-derived neurotrophic factor (GDNF) supports growth and survival of dopaminergic (DA) neurons. A replication-defective adenoviral (Ad) vector encoding human GDNF injected near the rat substantia nigra was found to protect DA neurons from the progressive degeneration induced by the neurotoxin 6-hydroxydopamine (6-OHDA) injected into the striatum. Ad GDNF gene therapy reduced loss of DA neurons approximately threefold 6 weeks after 6-OHDA lesion, as compared with no treatment or injection of Ad lacZ or Ad mGDNF (encoding a biologically inactive deletion mutant GDNF). These results suggest that Ad vector-mediated GDNF gene therapy may slow the DA neuronal cell loss in humans with Parkinson's disease.


Journal ArticleDOI
TL;DR: It is concluded that CpG ODN are effective as immune adjuvants and are attractive as part of a tumor immunization strategy.
Abstract: Recent advances in our understanding of the immune response are allowing for the logical design of new approaches to cancer immunization. One area of interest is the development of new immune adjuvants. Immunostimulatory oligodeoxynucleotides containing the CpG motif (CpG ODN) can induce production of a wide variety of cytokines and activate B cells, monocytes, dendritic cells, and NK cells. Using the 38C13 B cell lymphoma model, we assessed whether CpG ODN can function as immune adjuvants in tumor antigen immunization. The idiotype served as the tumor antigen. Select CpG ODN were as effective as complete Freund’s adjuvant at inducing an antigen-specific antibody response but were associated with less toxicity. These CpG ODN induced a higher titer of antigen-specific IgG2a than did complete Freund’s adjuvant, suggesting an enhanced TH1 response. Mice immunized with CpG ODN as an adjuvant were protected from tumor challenge to a degree similar to that seen in mice immunized with complete Freund’s adjuvant. We conclude that CpG ODN are effective as immune adjuvants and are attractive as part of a tumor immunization strategy.

Journal ArticleDOI
TL;DR: In this paper, a longitudinal extension of previous findings about the critical role of temperamental inhibitory or effortful control as the contributor to developing conscience in young children was reported, with the increase with age, and gender differences, with girls outperforming boys.
Abstract: In this article we report a longitudinal extension of previous findings about the critical role of temperamental inhibitory or effortful control as the contributor to developing conscience in young children. A comprehensive observational battery, highly internally consistent, was developed to measure inhibitory control in 83 children at early school age who had been followed since toddlerhood and had been assessed using similar batteries at toddler and preschool age. We again confirmed the findings of robust longitudinal stability of inhibitory or effortful control, now from toddler to early school age, the increase with age, and gender differences, with girls outperforming boys. We also reaffirmed strong links, both contemporaneous and in the longitudinal sense, between inhibitory control and multiple, diverse measures of children's conscience at early school age, including observations of moral conduct, moral cognition, and moral self. The findings are discussed in view of the increasingly appreciated importance of temperament for critical aspects of socialization.

Journal ArticleDOI
TL;DR: Analysis of cerebral blood flow with positron emission tomography suggests distributed dysfunctional circuits may form the neural basis of schizophrenia through cognitive impairment of the brain, which prevents it from processing input efficiently and producing output effectively, thereby leading to symptoms such as hallucinations, delusions, and loss of volition.

Book ChapterDOI
Hantao Zhang1
13 Jul 1997
TL;DR: Two techniques that are found eeective to improve SATO performance are discussed, one is about splitting rules; the other is about connict analysis.
Abstract: SATO (Satissability Testing Optimized) is a propositional prover based on the Davis-Putnam method 3], which is is one of the major practical methods for the satissability (SAT) problem of propositional logic. The rst report of SATO appeared in 12]. Since then, we constantly add new techniques into SATO to make it more eecient 14, 13]. One of the major motivations to develop SATO was to attack open Latin square problems. While SATO works well on Latin square problems, its previous versions did not work well on many classes of the SAT problem. In the fall of 1996, we made an eeort to improve SATO so that it works well on a large set of the SAT problem. In the following, we discuss brieey two techniques that we found eeective to improve SATO performance. One is about splitting rules; the other is about connict analysis. While these two techniques are known in the community, the real challenge is how to integrate these techniques without weakening each other. We are happy to report here that the two techniques integrated very well with the techniques previously implemented in SATO. In the following discussions, we assume that the reader is familiar with propositional logic and the Davis-Putnam method 3]. One important place where heuristics may be inserted in the Davis-Putnam method is in the choice of a literal for splitting. It is well-known that diierent splitting rules make the performance of the Davis-Putnam algorithm diierent by a magnitude of several orders. While SATO provides several popular splitting rules, each rule works well only for a particular class of SAT instances. For instance, in our study of quasigroup problems, one rule seems better than the others: choose one literal in one of the shortest positive clauses (a positive clause is a clause where all the literals are positive). On the other hand, a proved eeective splitting rule is to choose a variable x such that the value f 2 (x)f 2 (:x) is maximal, where f 2 (L) is one plus the number of occurrences of literal L in binary clauses 2, 5]. We tried to combine the above two rules into one as follows: Let 0 < a 1 and n be the number of shortest non-Horn clauses in the current set. At rst, we collect all the variable names appearing in the rst da ne shortest positive clauses. Then we choose x in …

Journal ArticleDOI
TL;DR: In this article, the authors extend longitudinally findings on child temperament as a moderator of the impact of socialization on conscience development, reported previously for contemporaneous data at toddler age.
Abstract: This research extends longitudinally findings on child temperament as a moderator of the impact of socialization on conscience development, reported previously for contemporaneous data at toddler age. Children's temperament and maternal socialization at Time 1 (n = 103, aged 2-3 years) were considered predictors of future conscience, assessed using new observational and narrative measures. The moderation model was supported for predicting conscience at Time 2 (n = 99, age 4), and, to a lesser extent, at Time 3 (n = 90, age 5). For children fearful as toddlers, maternal gentle discipline, presumably capitalizing on the optimal level of anxious arousal, promoted conscience at Time 2. For children fearless as toddlers, perhaps insufficiently aroused by gentle discipline, alternative socialization mechanisms, presumably capitalizing on mother-child positive orientation (secure attachment, maternal responsiveness), promoted conscience at Times 2 and 3. Developmental interplay of temperament and socialization in emerging morality is discussed.

Journal ArticleDOI
TL;DR: The hypothesis that the normal retrieval of knowledge for concrete entities from different conceptual domains depends on partially segregated neural systems that is supported by the findings of this study is supported.

Journal ArticleDOI
TL;DR: It is shown that transformations constrained by quadratic regularization methods such as the Laplacian, biharmonic, and linear elasticity models, do not ensure that the transformation maintains topology and, therefore, must only be used for coarse global registration.
Abstract: Presents diffeomorphic transformations of three-dimensional (3-D) anatomical image data of the macaque occipital lobe and whole brain cryosection imagery and of deep brain structures in human brains as imaged via magnetic resonance imagery. These transformations are generated in a hierarchical manner, accommodating both global and local anatomical detail. The initial low-dimensional registration is accomplished by constraining the transformation to be in a low-dimensional basis. The basis is defined by the Green's function of the elasticity operator placed at predefined locations in the anatomy and the eigenfunctions of the elasticity operator. The high-dimensional large deformations are vector fields generated via the mismatch between the template and target-image volumes constrained to be the solution of a Navier-Stokes fluid model. As part of this procedure, the Jacobian of the transformation is tracked, insuring the generation of diffeomorphisms. It is shown that transformations constrained by quadratic regularization methods such as the Laplacian, biharmonic, and linear elasticity models, do not ensure that the transformation maintains topology and, therefore, must only be used for coarse global registration.