bluuebunny/crossref_metadata_2025 huggingface dataset:
TFE3 Fusions Activate MET Signaling by Transcriptional Up-regulation, Defining Another Class of Tumors as Candidates for Therapeutic MET Inhibition
Authors: Tsuda Masumi , Davis Ian J. , Argani Pedram , Shukla Neerav , McGill Gael G. , Nagai Makoto , Saito Tsuyoshi , Laé Marick , Fisher David E. , Ladanyi Marc
Published: February 2007

Specific chromosomal translocations encoding chimeric transcription factors are considered to play crucial oncogenic roles in a variety of human cancers but the fusion proteins themselves seldom represent suitable therapeutic targets. Oncogenic TFE3 fusion proteins define a subset of pediatric renal adenocarcinomas and one fusion (ASPL-TFE3) is also characteristic of alveolar soft part sarcoma (ASPS). By expression profiling, we identified the MET receptor tyrosine kinase gene as significantly overexpressed in ASPS relative to four other types of primitive sarcomas. We therefore examined MET as a direct transcriptional target of ASPL-TFE3. ASPL-TFE3 binds to the MET promoter and strongly activates it. Likewise, PSF-TFE3 and NONO-TFE3 also bind this promoter. Induction of MET by ASPL-TFE3 results in strong MET autophosphorylation and activation of downstream signaling in the presence of hepatocyte growth factor (HGF). In cancer cell lines containing endogenous TFE3 fusion proteins, inhibiting MET by RNA interference or by the inhibitor PHA665752 abolishes HGF-dependent MET activation, causing decreased cell growth and loss of HGF-dependent phenotypes. MET is thus a potential therapeutic target in these cancers. Aberrant transcriptional up-regulation of MET by oncogenic TFE3 fusion proteins represents another mechanism by which certain cancers become dependent on MET signaling. The identification of kinase signaling pathways transcriptionally up-regulated by oncogenic fusion proteins may reveal more accessible therapeutic targets in this class of human cancers. [Cancer Res 2007;67(3):919–29]
5-Fluorouracil Incorporated into DNA Is Excised by the Smug1 DNA Glycosylase to Reduce Drug Cytotoxicity
Authors: An Qian , Robins Peter , Lindahl Tomas , Barnes Deborah E.
Published: February 2007

5-Fluorouracil (FU) has been widely used for more than four decades in the treatment of a range of common cancers. The fluorine-substituted uracila analogue is converted to several active metabolites but the mechanism of cytotoxicity has remained unclear. In a widely cited but unsubstantiated model, FU is thought to kill cells via the inhibition of thymidylate synthase and increased use of dUTP in place of TTP during DNA replication, with subsequent excision of high levels of uracil causing the fragmentation of newly synthesized DNA. Using gene-targeted cell lines defective in one or both of the two mammalian uracil-DNA glycosylase repair enzymes, we were able to test this model of FU cytotoxicity. Here, we show that incorporation of FU itself into DNA has been previously underestimated and is a predominant cause of cytotoxicity. FU readily becomes incorporated into the DNA of drug-treated cells, and accumulation of FU in the genome, rather than uracil excision, is correlated with FU cytotoxicity in mammalian cells. Furthermore, the Smug1, but not the Ung, uracil-DNA glycosylase excises FU from DNA and protects against cell killing. The data provides a clearer understanding of the action of FU, suggesting predictive biomarkers of drug response and a mechanism for acquired resistance in tumors. [Cancer Res 2007;67(3):940–5]
Methylation-Independent Silencing of the Tumor Suppressor INK4b (p15) by CBFβ-SMMHC in Acute Myelogenous Leukemia with inv(16)
Authors: Markus Jan , Garin Matthew T. , Bies Juraj , Galili Naomi , Raza Azra , Thirman Michael J. , Le Beau Michelle M. , Rowley Janet D. , Liu P. Paul , Wolff Linda
Published: February 2007

The tumor suppressor gene INK4b (p15) is silenced by CpG island hypermethylation in most acute myelogenous leukemias (AML), and this epigenetic phenomenon can be reversed by treatment with hypomethylating agents. Thus far, it was not investigated whether INK4b is hypermethylated in all cytogenetic subtypes of AML. A comparison of levels of INK4b methylation in AML with the three most common cytogenetic alterations, inv(16), t(8;21), and t(15;17), revealed a strikingly low level of methylation in all leukemias with inv(16) compared with the other types. Surprisingly, the expression level of INK4b in inv(16)+ AML samples was low and comparable with that of the other subtypes. An investigation into an alternative mechanism of INK4b silencing determined that the loss of INK4b expression was caused by inv(16)-encoded core binding factor β-smooth muscle myosin heavy chain (CBFβ-SMMHC). The silencing was manifested in an inability to activate the normal expression of INK4b RNA as shown in vitamin D3–treated U937 cells expressing CBFβ-SMMHC. CBFβ-SMMHC was shown to displace RUNX1 from a newly determined CBF site in the promoter of INK4b. Importantly, this study (a) establishes that the gene encoding the tumor suppressor p15INK4b is a target of CBFβ-SMMHC, a finding relevant to the leukemogenesis process, and (b) indicates that, in patients with inv(16)-containing AML, reexpression from the INK4b locus in the leukemia would not be predicted to occur using hypomethylating drugs. [Cancer Res 2007;67(3):992–1000]
Low-Dose Irradiation of Nontransformed Cells Stimulates the Selective Removal of Precancerous Cells via Intercellular Induction of Apoptosis
Authors: Portess Daniel I. , Bauer Georg , Hill Mark A. , O'Neill Peter
Published: February 2007

An important stage in tumorigenesis is the ability of a precancerous cell to escape natural anticancer signals imposed on it by neighboring cells and its microenvironment. We have previously characterized a system of intercellular induction of apoptosis whereby nontransformed cells selectively remove transformed cells from coculture via cytokine and reactive oxygen/nitrogen species (ROS/RNS) signaling. We report that irradiation of nontransformed cells with low doses of either high linear energy transfer (LET) α-particles or low-LET γ-rays leads to stimulation of intercellular induction of apoptosis. The use of scavengers and inhibitors confirms the involvement of ROS/RNS signaling and of the importance of transformed cell NADPH oxidase in the selectivity of the system. Doses as low as 2-mGy γ-rays and 0.29-mGy α-particles were sufficient to produce an observable increase in transformed cell apoptosis. This radiation-stimulated effect saturates at very low doses (50 mGy for γ-rays and 25 mGy for α-particles). The use of transforming growth factor-β (TGF-β) neutralizing antibody confirms a role for the cytokine in the radiation-induced signaling. The system may represent a natural anticancer mechanism stimulated by extremely low doses of ionizing radiation. [Cancer Res 2007;67(3):1246–53]
Endogenous Cytosine Damage Products Alter the Site Selectivity of Human DNA Maintenance Methyltransferase DNMT1
Authors: Valinluck Victoria , Sowers Lawrence C.
Published: February 2007

Alterations in cytosine methylation patterns are usually observed in human tumors. The consequences of altered cytosine methylation patterns include both inappropriate activation of transforming genes and silencing of tumor suppressor genes. Despite the biological effect of methylation changes, little is known about how such changes are caused. The heritability of cytosine methylation patterns from parent to progeny cells is attributed to the fidelity of the methylation-sensitive human maintenance methyltransferase DNMT1, which methylates with high specificity the unmethylated strand of a hemimethylated CpG sequence following DNA replication. We have been studying DNA damage that might alter the specificity of DNMT1, either inhibiting the methylation of hemimethylated sites or triggering the inappropriate methylation of previously unmethylated sites. Here, we show that known forms of endogenous DNA damage can cause either hypermethylation or hypomethylation. Inflammation-induced 5-halogenated cytosine damage products, including 5-chlorocytosine, mimic 5-methylcytosine and induce inappropriate DNMT1 methylation within a CpG sequence. In contrast, oxidation damage of the methyl group of 5-methylcytosine, with the formation of 5-hydroxymethylcytosine, prevents DNMT1 methylation of the target cytosine. We propose that reduced DNMT1 selectivity resulting from DNA damage could cause heritable changes in cytosine methylation patterns, resulting in human tumor formation. These data may provide a mechanistic link for the associations documented between inflammation and cancer. [Cancer Res 2007;67(3):946–50]
Peptide Vaccine Given with a Toll-Like Receptor Agonist Is Effective for the Treatment and Prevention of Spontaneous Breast Tumors
Authors: Nava-Parada Pilar , Forni Guido , Knutson Keith L. , Pease Larry R. , Celis Esteban
Published: February 2007

Our goal is to develop peptide vaccines that stimulate tumor antigen–specific T-cell responses against frequently found cancers. Previous work has shown that to generate effective T-cell responses, peptides have to be administered in combination with strong adjuvants such as Toll-like receptor agonists. However, most animal tumor model systems used to study peptide vaccines were not truly representative of malignant diseases in humans because they solely used transplantable tumor lines, and instead of true tumor antigens, they used highly immunogenic foreign proteins. Here, we describe a peptide vaccination strategy, which is highly effective in delaying or preventing the occurrence of spontaneous breast tumors. Transgenic female BALB-neuT mice that carry the activated rat HER-2/neu oncogene were vaccinated with a synthetic peptide from the rat HER-2/neu gene product, which represents an epitope for CTLs in combination with a Toll-like receptor agonist adjuvant. Our results show that to obtain tumor antigen-specific CTL responses and antitumor effects, the vaccine had to be administered repetitively, or the function of CD4/CD25 T regulatory cells had to be blocked with anti-CD25 antibody therapy. Mice that were vaccinated with this approach remained tumor-free or were able to control spontaneous tumor growth and exhibited long-lasting CTL responses, not only against the immunizing peptide but also against other peptides derived from rat HER-2/neu product (i.e., epitope spreading). These results suggest that similar strategies should be followed for conducting clinical studies in patients. [Cancer Res 2007;67(3):1326–34]
HIV Protease Inhibitor Nelfinavir Inhibits Growth of Human Melanoma Cells by Induction of Cell Cycle Arrest
Authors: Jiang Wei , Mikochik Peter J. , Ra Jin H. , Lei Hanqin , Flaherty Keith T. , Winkler Jeffrey D. , Spitz Francis R.
Published: February 2007

HIV protease inhibitors (HIV PI) are a class of antiretroviral drugs that are designed to target the viral protease. Unexpectedly, this class of drugs is also reported to have antitumor activity. In this study, we have evaluated the in vitro activity of nelfinavir, a HIV PI, against human melanoma cells. Nelfinavir inhibits the growth of melanoma cell lines at low micromolar concentrations that are clinically attainable. Nelfinavir promotes apoptosis and arrests cell cycle at G1 phase. Cell cycle arrest is attributed to inhibition of cyclin-dependent kinase 2 (CDK2) and concomitant dephosphorylation of retinoblastoma tumor suppressor. We further show that nelfinavir inhibits CDK2 through proteasome-dependent degradation of Cdc25A phosphatase. Our results suggest that nelfinavir is a promising candidate chemotherapeutic agent for advanced melanoma, for which novel and effective therapies are urgently needed. [Cancer Res 2007;67(3):1221–7]
Targeted and Nontargeted Effects of Low-Dose Ionizing Radiation on Delayed Genomic Instability in Human Cells
Authors: Huang Lei , Kim Perry M. , Nickoloff Jac A. , Morgan William F.
Published: February 2007

All humans receive some radiation exposure and the risk for radiation-induced cancer at low doses is based on the assumption that there is a linear non-threshold relationship between dose and subsequent effect. Consequently, risk is extrapolated linearly from high radiation doses to very low doses. However, adaptive responses, bystander effects, and death-inducing effect may influence health effects associated with low-dose radiation exposure. Adaptive response is the phenomenon by which cells irradiated with a sublethal radiation dose can become less susceptible to subsequent high-dose radiation exposure. Bystander effects are nontargeted effects observed in cells that were not irradiated but were either in contact with or received soluble signals from irradiated cells. These non-hit bystander cells can exhibit damage typically associated with direct radiation exposure. Death-inducing effect is a phenomenon whereby medium from human-hamster hybrid cells displaying radiation-induced chromosomal instability is toxic to unirradiated parental cells. In this study, we show that human RKO cells do not exhibit adaptive response, bystander effect, or death-inducing effect, as measured by cell killing, or delayed genomic instability in a stably transfected plasmid–based green fluorescent protein assay measuring homologous recombination and delayed mutation/deletion events. However, growth medium conditioned by some chromosomally unstable RKO derivatives induced genomic instability, indicating that these cells can secrete factor(s) that elicit responses in nonirradiated cells. Furthermore, low radiation doses suppressed the induction of delayed genomic instability by a subsequent high dose, indicative of an adaptive response for radiation-induced genomic instability. These results highlight the inherent variability in cellular responses to low-dose radiation exposure and add to the uncertainties associated with evaluating potential hazards at these low doses. [Cancer Res 2007;67(3):1099–104]
Perspectives on the Research History of Giyoo Hatano
Authors: Inagaki Kayoko , Miyake Naomi
Published: February 2007

In this article, we trace the development of Hatano’s research, focusing on the core of his research interest, namely, expertise, conceptual development, and classroom learning. He held both Piagetian constructivist views and Vygotskian sociocultural perspectives in balance, and preferred to study human cognition executed in everyday life. This brief review strongly suggests that Hatano consciously or subconsciously introduced Japanese perspectives into the areas of human development and education, which often contributed to the expansion and enrichment of mainstream viewpoints constructed within the context of the Occidental research culture.
Biology and Beyond: Domain Specificity in a Broader Developmental Context
Authors: Keil Frank C.
Published: February 2007

The assumption of domain specificity has been invaluable to the study of the emergence of biological thought in young children. Yet, domains of thought must be understood within a broader context that explains how those domains relate to the surrounding cultures, to different kinds of cognitive constraints, to framing effects, to abilities to evaluate knowledge and to the ways in which domain-specific knowledge in any individual mind is related to knowledge in other minds. All of these issues must come together to have a full account of conceptual development in biology.
Changing Conceptual Change
Authors: diSessa Andrea A.
Published: February 2007

This article reviews Giyoo Hatano’s ground-breaking theoretical, empirical, and methodological contributions to conceptual change research. In particular, his discovery of ‘vitalism’ as part of children’s legitimate and distinctive biology at early ages stands as a landmark. In addition, his work reinterpreted childhood ‘personification,’ changing it from an indicator of deficient intellect, to a creative and often insightful strategy for coming to understand biology.
A Spatial Analysis of Loop Closing Among Recycling, Remanufacturing, and Waste Treatment Firms in Texas
Authors: Lyons Donald I.
Published: February 2007

Industrial ecology has emerged as a key strategy for improving environmental conditions. A central element of industrial ecology is the concept of closing the loop in material use (cycling) by directing used material and products (wastes) back to production processes. This article examines the issue of geographic scale and loop closing for heterogeneous wastes through an analysis of the location and materials flows of a set of recycling, remanufacturing, recycling manufacturing, and waste treatment (RRWT) firms in Texas. The results suggest that there is no preferable scale at which loop closing should be organized. RRWT firms are ubiquitous and operate successfully throughout the settlement hierarchy. The cycling boundaries of RRWT firms are dependent primarily upon how and where their products are redirected to production processes rather than the firm's location in the settlement hierarchy. In other words, loop closing is dominated by the spatial economic logic of the transactions of the firm involved. These results suggest that we cannot assign loop closing to any particular spatial scale a priori nor can we conceive of closing the loop via RRWT firms in terms of monolithic networks bounded in space or place with internal material flows.
Material Flows in a Social Context: A Vietnamese Case Study Combining the Materials Flow Analysis and Action‐in‐Context Frameworks
Authors: HOBBES Marieke , STALPERS Serge I. P. , KOOIJMAN Jiska , LE Thi Thu Thanh , TRINH Khanh Chi , PHAN Thi Anh Dao
Published: February 2007

Materials flow analysis (MFA) is one of the central achievements of industrial ecology. One direction in which one can move MFA beyond mere accounting is by putting the material flows in their social context. This “socially extended MFA” may be carried out at various levels of aggregation. In this article, specific material flows will be linked to concrete actors and mechanisms that cause these flows—using the action‐in‐context (AiC) framework, which contains, inter alia, both proximate and indirect actors and factors. The case study site is of Tat hamlet in Vietnam, set in a landscape of paddy fields on valley floors surrounded by steep, previously forested slopes. Out of the aggregate MFA of Tat, the study focuses on material flows associated with basic needs and sustainability. The most important actors causing these material flows are farming households, politicians, traders, and agribusiness firms—of which local politicians turned out to be pivotal. The study shows the value of combining MFA with actor‐based social analysis. MFA achieves the balanced quantification of the physical system, thus helping to pinpoint key processes. Actor‐based analysis adds the causal understanding of what drives these key processes, leading to improved scenarios of the future and the effective identification of target groups and instruments for policy making.
Developing Markets for Certified Wood Products: Greening the Supply Chain for Construction Materials
Authors: Irland Lloyd C.
Published: February 2007

A growing worldwide movement is seeking to promote the greening of the construction sector. At the design level, proponents of frameworks such as LEED (Leadership in Energy and Environmental Design) seek to motivate designers and building owners to employ environmentally desirable materials. A prominent component of this approach is boosting availability of “green” building materials through programs that will certify to buyers that materials meet environmental standards. For wood products, this has resulted in several forms of “green certification” for forest management. Increasingly large areas of forest are now being certified worldwide. Yet it remains difficult for designers of green buildings, or consumers seeking green furniture, to obtain certified wood products.

Many, if not most, of the logs now being harvested on green certified forest land worldwide are not reaching the store shelf with a certified label. Marketing certified wood all the way to the retail shelf has proved to be much harder than initially thought by proponents of certified products. This article explains the sources of these difficulties and outlines an approach to identifying products with high potential for marketing as certified products. Because of complex, multilevel supply chains for many wood products, support is required at all processing and distribution levels for a product to reach the retail customer with its green label.

Market participants' purchase size and frequency, basis for product selection, buying influences, and price sensitivity are evaluated to identify product and market approaches likely to increase success rates for certified wood products. The article concludes with recommendations for expanding markets for green building materials.
Material Flows and Economic Growth in Developing China
Authors: XU Ming , ZHANG Tianzhu
Published: February 2007

The concept of sustainable development concerns not only the natural environment but also human societies and economies. The method of economy‐wide materials flow accounting and analysis (EW‐MFA) is internationally recognized as a valuable tool for studying the physical dimensions of economies. EW‐MFA has been carried out in many industrialized countries, but very little work has been done for developing China; this article can be regarded as one of the first attempts to study China's economy in terms of materials flows. In this article we have compiled materials flow accounts for China during the time series 1990 to 2002 and derived indicators associated with international comparison. Results show that the annual material consumption of China's economy continuously increased except for a slump around 1998, whereas the material efficiency exhibited a three‐phase trend reflecting different macropolicies of the Eighth, Ninth, and Tenth Five‐Year Plans implemented by the central government. Based on this experience with EW‐MFA for China, suggestions for methodology development and further research are given for improving EW‐MFA as a more effective tool for environmental management.
Modeling Biowaste Flows for Life‐Cycle Assessment: Calculation of the Potential and Collected Weight of Kitchen and Garden Waste
Authors: Schmidt Sonja , Pahl‐Wostl Claudia
Published: February 2007

This article presents an integrative approach to calculating the weight of potential biowaste and collected biowaste materials, as the basis for a life‐cycle assessment (LCA) of biowaste management. Biowaste contains kitchen and garden (yard) waste of households. This approach could be used for waste management planning and for the implementation of biowaste schemes. Case studies and examples in the literature are analyzed to model the mass of the flow of biowaste. This article defines relevant operands, presents the main assumptions, and describes the calculation principles. Spatial aspects and the uncertainties related to the inclusion of this aspect are explicitly considered in the calculation of the weight of the potential biowaste. We also present the calculation principles for obtaining the weight of (1) biowaste used in home composting, (2) the organic portion of residual waste, (3) biowaste separately collected by a bring system, and (4) biowaste separately collected by curbside collection (known in some areas as kerbside collection). By choosing the biowaste potential in kilograms per capita year (kg/cap yr) as the functional unit, previously ignored options within the biowaste system could be assessed. For example, widening the system boundaries allows LCA studies to assess the contribution of private and public transport of waste to ecological impact categories. It allows examining the effects of supporting home composting through financial incentives and the introduction of a separate collection system. This study focuses on the comparison of different collection types and on the characteristics of the area under investigation. It also incorporates the behavior of the inhabitants of households and includes a sensitivity analysis of relevant operands. This approach is being included in an LCA assessing biowaste management options.
Would Industrial Ecology Exist without Sustainability in the Background?
Authors: Ehrenfeld John R.
Published: February 2007

Industrial ecology rests historically—even in a short lifetime of 15 years or so—on the metaphorical power of natural ecosystems. Its evolution parallels the rise of concerns over unsustainability, that is, the threats to our world's ability to support human life the emergence of sustainability as a normative goal on a global scale. This article examines the relationships between industrial ecology and sustainability and argues that, in its historical relationship to classical ecology models, the field lacks power to address the full range of goals of sustainability, however defined. The classical ecosystem analogy omits aspects of human social and cultural life central to sustainability. But by moving beyond this model to more recent ecosystem models based on complexity theory, the field can expand its purview to address sustainability more broadly and powerfully. Complexity models of living systems can also ground alternative normative models for sustainability as an emergent property rather than the output of a mechanistic economic model for society's workings.
Intermanual Differences in Movement-related Interhemispheric Inhibition
Authors: Duque Julie , Murase Nagako , Celnik Pablo , Hummel Friedhelm , Harris-Love Michelle , Mazzocchio Riccardo , Olivier Etienne , Cohen Leonardo G.
Published: February 2007

Interhemispheric inhibition (IHI) between motor cortical areas is thought to play a critical role in motor control and could influence manual dexterity. The purpose of this study was to investigate IHI preceding movements of the dominant and nondominant hands of healthy volunteers. Movement-related IHI was studied by means of a double-pulse transcranial magnetic stimulation protocol in right-handed individuals in a simple reaction time paradigm. IHI targeting the motor cortex contralateral (IHIc) and ipsilateral (IHIi) to each moving finger was determined. IHIc was comparable after the go signal, a long time preceding movement onset, in both hands. Closer to movement onset, IHIc reversed into facilitation for the right dominant hand but remained inhibitory for left nondominant hand movements. IHIi displayed a nearly constant inhibition with a trough early in the premovement period in both hands. In conclusion, our results unveil a more important modulation of interhemispheric interactions during generation of dominant than nondominant hand movements. This modulation essentially consisted of a shift from a balanced IHI at rest to an IHI predominantly directed toward the ipsilateral primary motor cortex at movement onset. Such a mechanism might release muscles from inhibition in the contralateral primary motor cortex while preventing the occurrence of the mirror activity in ipsilateral primary motor cortex and could therefore contribute to intermanual differences in dexterity.
Dissociation between Striatal Regions while Learning to Categorize via Feedback and via Observation
Authors: Cincotta Corinna M. , Seger Carol A.
Published: February 2007

Convergent evidence from functional imaging and from neuropsychological studies of basal ganglia disorders indicates that the striatum is involved in learning to categorize visual stimuli with feedback. However, it is unclear which cognitive process or processes involved in categorization is or are responsible for striatal recruitment; different regions of the striatum have been linked to feedback processing and to acquisition of stimulus-category associations. We examined the effect of the presence of feedback during learning on striatal recruitment by comparing feedback learning with observational learning of an information integration task. In the feedback task, participants were shown a stimulus, made a button press response, and then received feedback as to whether they had made the correct response. In the observational task, participants were given the category label before the stimulus appeared and then made a button press indicating the correct category membership. A region-of-interest analysis was used to examine activity in three regions of the striatum: the head of the caudate, body and tail of the caudate, and the putamen. Activity in the left head of the caudate was modulated by the presence of feedback: The magnitude of activation change was greater during feedback learning than during observational learning. In contrast, the bilateral body and tail of the caudate and the putamen were active to a similar degree in both feedback and observational learning. This pattern of results supports a functional dissociation between regions of the striatum, such that the head of the caudate is involved in feedback processing, whereas the body and tail of the caudate and the putamen are involved in learning stimulus-category associations. The hippocampus was active bilaterally during both feedback and observational learning, indicating potential parallel involvement with the striatum in information integration category learning.
Maintenance of Visual Stability in the Human Posterior Parietal Cortex
Authors: Chang Erik , Ro Tony
Published: February 2007

Visual stability refers to our stable visuospatial perceptions despite the unstable visual input caused by saccades. Functional neuroimaging results, studies on patients with posterior parietal cortex (PPC) lesions, and single-unit recordings in the lateral intraparietal sulcus of primates indirectly suggest that the PPC might be a potential locus of visual stability through its involvement with spatial remapping. Here we directly explored the role of the PPC in visual stability by applying transcranial magnetic stimulation (TMS) while participants performed a perisaccadic displacement detection task. We show that TMS over the PPC but not a frontal control site alters sensitivity to displacement detection when administered just before contralateral saccades and that a general impairment in attention or in the perception of apparent motion cannot account for the decreased sensitivity. The specific relationship between the timing of TMS and saccade direction demonstrates that saccadic suppression of displacement (SSD) is likely a consequence of noisy contralateral spatial representations in the PPC around the time of a saccade. The same mechanism may keep the unstable visual world in the temporal proximity of saccades from reaching our consciousness.
Deceiving Others: Distinct Neural Responses of the Prefrontal Cortex and Amygdala in Simple Fabrication and Deception with Social Interactions
Authors: Abe Nobuhito , Suzuki Maki , Mori Etsuro , Itoh Masatoshi , Fujii Toshikatsu
Published: February 2007

Brain mechanisms for telling lies have been investigated recently using neuroimaging techniques such as functional magnetic resonance imaging and positron emission tomography. Although the advent of these techniques has gradually enabled clarification of the functional contributions of the prefrontal cortex in deception with respect to executive function, the specific roles of subregions within the prefrontal cortex and other brain regions responsible for emotional regulation or social interactions during deception are still unclear. Assuming that the processes of falsifying truthful responses and deceiving others are differentially associated with the activities of these regions, we conducted a positron emission tomography experiment with 2 (truth, lie) × 2 (honesty, dishonesty) factorial design. The main effect of falsifying the truthful responses revealed increased brain activity of the left dorsolateral and right anterior prefrontal cortices, supporting the interpretation of previous studies that executive functions are related to making untruthful responses. The main effect of deceiving the interrogator showed activations of the ventromedial prefrontal (medial orbitofrontal) cortex and amygdala, adding new evidence that the brain regions assumed to be responsible for emotional processing or social interaction are active during deceptive behavior similar to that in real-life situations. Further analysis revealed that activity of the right anterior prefrontal cortex showed both effects of deception, indicating that this region has a pivotal role in telling lies. Our results provide clear evidence of functionally dissociable roles of the prefrontal subregions and amygdala for human deception.
Activity in the Visual Cortex is Modulated by Top-Down Attention Locked to Reaction Time
Authors: Moradi Farshad , Hipp Constanze , Koch Christof
Published: February 2007

We studied the correlation between perception and hemodynamic activity in the visual cortex in a change detection task. Whenever the observer perceived the location of a change, rightly or wrongly, the blood oxygenation level-dependent signal increased in the primary visual cortex and the nearby extrastriate areas above the baseline activity caused by the visual stimulation. This non-sensory-evoked activity was localized and corresponded to the perceived location of the change. When a change was missed, or when observers attended to a different task, the change failed to evoke such a response. The latency of the nonsensory component increased linearly with subjects' reaction time, with a slope of one, and its amplitude was independent of contrast. Control experiments are compatible with the hypothesis that the nonsensory hemodynamic signal is mediated by top-down spatial attention, linked to (but separate from) awareness of the change.
Modulation of Memory Formation by Stimulus Content: Specific Role of the Medial Prefrontal Cortex in the Successful Encoding of Social Pictures
Authors: Harvey Philippe-Olivier , Fossati Philippe , Lepage Martin
Published: February 2007

It is unclear whether the involvement of the medial prefrontal cortex (mPFC) during encoding is restricted to the evaluative processing of to-be-encoded stimuli or if it is instead actively engaged during memory formation. The difficulty of assessing the contribution of the mPFC to encoding based on previous neuroimaging studies partly arises from the use of several types of stimuli, such as emotional or social ones. These different types of stimulus content could differently modulate mPFC activity during memory formation and thus partly explain the variable contribution of this region to encoding. Using emotional/neutral and social/nonsocial pictures, we conducted an event-related functional magnetic resonance imaging study using a subsequent memory paradigm as the main analytical strategy. We observed that the brain activity in the dorsal and orbital mPFC is significantly and specifically predictive of the successful encoding of social compared with nonsocial pictures. In contrast, the activity in the amygdala specifically predicts the successful encoding of emotional compared with neutral pictures. The modulation of the mPFC by social information in a memory encoding context could be associated with the initiation of self-referential processes whose contribution is to enhance memory formation.
From ‘A Clash of Civilizations’ to ‘Internal Colonialism’
Authors: Capetillo-Ponce Jorge
Published: February 2007

In his essay ‘The Hispanic Challenge’, Samuel Huntington argues that the persistent flow of Latino (and especially Mexican) immigrants into the USA threatens to divide the USA into ‘two peoples, two cultures and two languages’. Most critics have dismissed the essay by focusing on the data Huntington presents so polemically, and on his rigid conception of ‘Anglo-Protestant culture’. And yet very few have analyzed it by looking closely at the theoretical tradition that Huntington’s work both stands in and furthers. Thus, the main objective of this commentary is to reveal that Huntington is working from within the conflict model of cultural pluralism, and especially its internal-colonialist type.
Attitudes toward the Xeno: Greece in Comparative Perspective
Authors: Karakatsanis Neovi M. , Swarts Jonathan
Published: February 2007

Neovi M. Karakatsanis is professor of political science at Indiana University, South Bend.

Jonathan Swarts is professor of social sciences at Purdue University North Central, Westville, Indiana.
Lithium Ion Attachment Mass Spectrometry for the Direct Detection of Organoarsenic Compounds in the Metallomics Studies
Authors: Chen Lei , Suzuki Yaeko , Korenaga Takashi
Published: February 2007

In this study, three organoarsenic compounds including dimethylarsinic acid, trimethylarsine oxide, and arsenic ethoxide were directly detected by coupling a direct sample insertion probe with a lithium ion attachment mass spectrometer. Previously only gaseous sample could be detected by this method; however, solid and liquid samples can also be detected directly with the use of a direct sample insertion probe. This method will be applicable for the direct analysis of various organometallic compounds in the latest metallomics studies.
Enhancement of Light-induced Nucleation of Lysozyme in the Presence of Polyethylene Glycol (PEG) 4000
Authors: Okutsu Tetsuo , Sato Masaki , Furuta Kenji , Fujinaga Yuko , Horota Kumiko , Obi Kinichi , Horiuchi Hiroaki , Hiratsuka Hiroshi
Published: February 2007

Light-induced nucleation of protein was greatly enhanced by an addition of polyethylene glycol (PEG) 4000. PEG affects to increase reaction rate of the photochemical intermediate to produce lysozyme dimer which is responsible for the light-induced nucleation.
Highly Conductive Polyaniline Doped with DEHSSA Synthesized in Different Protonic Acids
Authors: Lee Kwong-Seng , Hino Tetsuo , Kuramoto Noriyuki
Published: February 2007

Conductive polyanilines doped with di-2-ethylhexylsulfosuccinic acid (DEHSSA) were synthesized in different inorganic acids through emulsion polymerization. A comparison of secondary doping effect by m-cresol on the backbone conformation of the polyaniline and electrical conductivity of these samples were performed. The conductivity increases with increasing m-cresol and the highest conductivity obtained was 384 S/cm for DEHSSA-doped PANI synthesized in hydrochloric acid (HCl).
Novel 1D Hydrophobic Pore Formation by C-Terminal Amide-controlled Self-assembly of Leu–Leu–Leu–NH2 in Crystal
Authors: In Yasuko , Ishida Toshimasa
Published: February 2007

A unique hydrophobic pore is generated by the self-assembly of Leu–Leu–Leu–NH2 (1) in the crystal structure, in which the C-terminal amide groups induce the cylindrical arrangement of Leu side chains by intermolecular NH···O hydrogen bonds. This body-centered cubic-type pore provides a structural basis for devising the material to selectively extract low-molecular hydrophobic molecule such as methane.
Applications of Single-site Photocatalysts Implanted within the Silica Matrixes of Zeolite and Mesoporous Silica
Authors: Yamashita Hiromi , Mori Kohsuke
Published: February 2007

The tetrahedrally coordinated metal oxide (titanium, vanadium, chromium, and molybdenum oxides) moieties can be implanted and isolated in the silica matrixes of microporous zeolite and mesoporous silica materials and named as “single-site photocatalysts.” Under UV-light irradiation these single-site photocatalysts form the charge-transfer excited state, i.e., the excited electron–hole pair state which localizes quite near to each other as compared to the electron and hole produced in semiconducting materials, plays a significant role in various photocatalytic reactions. Especially, the single-site titanium oxide photocatalyst demonstrates the high reactivity and selectivity under UV-light irradiation, while the single-site chromium oxide operates as a visible-light sensitive photocatalyst. These single-site photocatalysts not only can promote photocatalytic reactions but also can be utilized to synthesis of functional materials. The transparent mesoporous thin film with single-site photocatalyst generates the superhydrophilic surface. The nano-sized metal catalyst can be photodeposited on the excited single-site photocatalyst under UV-light irradiation.
Synthesis of Tricyclo[3.1.0.02,4]hexasilane and Its Photochemical Isomerization to Tricyclo[2.2.0.02,5]hexasilane
Authors: Iwamoto Takeaki , Uchiyama Kei , Kabuto Chizuko , Kira Mitsuo
Published: February 2007

The first anti-tricyclo[3.1.0.02,4]hexasilane 1 was synthesized as pale yellow crystals. Irradiation (λ > 370 nm) of 1 gave its skeletal isomer, tricyclo[2.2.0.02,5]hexasilane 2, in 80% yield. The photochemical [σ2s + σ2s] cycloreversion of 1 followed by the thermal [π2s + π2a] cycloaddition to 2 would explain the overall isomerization.
Reversible Luminescence Modulation in Photochromic Europium(III) Complex Having Triangle Terthiazole Ligands
Authors: Nakagawa Tetsuya , Atsumi Kazuhiko , Nakashima Takuya , Hasegawa Yasuchika , Kawai Tsuyoshi
Published: February 2007

Luminescent EuIII complex having photochromic ligand is synthesized, and its reversible control of the luminescent properties based on photochromic reaction was demonstrated.
Efficient Conversion of NO2 into N2 and O2 in N2 or into N2O5 in Air by 172-nm Xe2 Excimer Lamp at Atmospheric Pressure
Authors: Tsuji Masaharu , Kawahara Masashi , Senda Makoto , Noda Kenji
Published: February 2007

Decomposition of NO2 (200 ppm) in N2 or air by 172-nm Xe2 excimer lamp was studied at 1 atm. The NO2 conversion in N2 was 99%, and the formation ratios of N2, O2, NO, and N2O were 47, 98, 0, and 2%, respectively, after 30 min irradiation. The NO2 in air (5–20% O2) could be completely converted to N2O5 and HNO3 due to reactions by O3 and H2O after only 1.0–1.5 min irradiation. The present results give a new simple photochemical aftertreatment technique of NO2 in air without using any catalysts.
Scandium Ion-accelerated Scavenging Reaction of Cumylperoxyl Radical by a Cyclic Nitroxyl Radical via Electron Transfer
Authors: Nakanishi Ikuo , Kawaguchi Kumiko , Ohkubo Kei , Kawashima Tomonori , Manda Sushma , Kanazawa Hideko , Takeshita Keizo , Anzai Kazunori , Ozawa Toshihiko , Fukuzumi Shunichi , Ikota Nobuo
Published: February 2007

A cyclic nitroxyl radical used as a spin probe efficiently scavenges cumylperoxyl radical in an aprotic medium via an electron-transfer process, which is significantly accelerated by the presence of scandium ion.
DNA Conformational Switching by Use of an Intercalator and Its Receptor
Authors: Nishimura Tomoki , Takeda Yoichi , Shimada Naohiko , Sakurai Kazuo
Published: February 2007

DNA conformational switching between B and Z forms was controlled with tilorone (intercalator) and sulfocalix[8]arene (C8AS, receptor for tilorone). When tilorone was added to the Z-DNA that had been beforehand induced by cobalt hexamine, the conformational transition from Z to B form was induced. The resultant B-DNA was turned back to Z-DNA by adding C8AS. This change was a clear-cut transition because most of the intercalated tilorone molecules were pulled out and captured by C8AS. This mechanism was established by isothermal titration calorimetry in which the binding constant of tilorone to C8AS was shown twice larger than that of tilorone/DNA.
Morphological Control to Kneed Gold Nanowire through Initial Mixing in Polyol Process
Authors: Lee Jong-Hee , Kamada Kai , Enomoto Naoya , Hojo Junichi
Published: February 2007

Various kneed gold nanowires with unique morphology were prepared by reducing hydrogen tetrachloroaurate through polyol process in the presence of polyvinylpyrrolidone (PVP). The kneed nanowires were ca. 150 nm in thickness and ca. 14 μm in length. Initial injection and dropping rate of hydrogen tetrachloroaurate (HAuCl4) and PVP solutions into ethylene glycol were keys to induce formation of kneed gold nanowires.
A Multilevel Investigation of the Motivational Mechanisms Underlying Knowledge Sharing and Performance
Authors: Quigley Narda R. , Tesluk Paul E. , Locke Edwin A. , Bartol Kathryn M.
Published: February 2007

This study draws on three different, yet complementary, theories of motivation, which we combine in an interactive manner, to explain the mechanisms that underlie the exchange between knowledge providers and recipients and ultimately impact performance. More specifically, we use incentive, goal-setting-social cognitive, and social motivation theories to examine knowledge sharing within dyads and its influence on individual performance. One hundred and twenty participants functioning as interdependent manager dyads completed a strategic decision-making simulation. Hierarchical regression and random coefficient modeling techniques were used to test hypothesized relationships. Results demonstrated that the effect of group-oriented incentive systems on the knowledge provider was enhanced when more positive norms for knowledge sharing existed among dyad members. The recipient’s self-efficacy had a stronger relationship with performance goals when the recipient trusted the provider. Finally, self-set goals and knowledge sharing had both direct and interactive effects on individual performance. We argue that these findings constitute a useful advance in middle-range motivation (Landy and Becker 1987, Pinder 1984) theory pertaining to knowledge sharing and utilization.
Coordinating Expertise Among Emergent Groups Responding to Disasters
Authors: Majchrzak Ann , Jarvenpaa Sirkka L. , Hollingshead Andrea B.
Published: February 2007

In the aftermath of catastrophic events, when plans for organized and timely response break down, impromptu groups often emerge to provide disaster relief. Much remains to be learned about the internal dynamics of these emergent response groups whose representatives may include members from organizations with relief missions; private sector organizations offering resources; and private citizens with the information, relationships, or physical and mental stamina to help. Organizational theories have the potential to contribute to a better understanding of emergent response groups and how they efficiently coordinate knowledge, people, resources, tasks, and technology, thereby substantially improving disaster response for future catastrophes. We apply one organization science theory toward better understanding of these groups—transactive memory systems theory—which is a theory about knowledge coordination in groups. Our application of this theory to emergent response groups requires extending the theory in three ways: the role of expertise in task assignment, how groups function when credibility in member expertise cannot be validated, and how expertise is coordinated. By demonstrating how transactive memory systems theory can be extended to the unique operating conditions of emergent response groups, we hope to inspire organization science researchers to accept the challenge of adapting their theories to study this important problem of our time.
Organizations Non Gratae? The Impact of Unethical Corporate Acts on Interorganizational Networks
Authors: Sullivan Bilian Ni , Haunschild Pamela , Page Karen
Published: February 2007

In this study, we examine the effects of illegal/unethical acts on interfirm networks. We hypothesize that the quality of network partners will decline and overall network structure will change after a firm commits an unethical act. More specifically, we posit that the decline in partner quality is primarily driven by higher quality firms leaving the network, and the focal firm being forced to replace them with lower quality ones. We also propose that partner prominence and network cohesion will be affected after these acts, and that the changes in partner quality and network structure will be greater for those acts perceived as more illegitimate. We test these hypotheses using a sample of 200 large firms in the United States and data on unethical acts by these firms. Our results show that the quality of a firm’s network partners declines after the firm’s commission of an unethical act, and that the deterioration in partner quality tends to be greater for acts of greater illegitimacy. Our results also show declines in network prominence and cohesion for firms involved in these activities. We discuss the implications of our results for the literatures on interfirm networks and unethical corporate activities.