bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolism of flavoneC-glucosides andp-coumaric acid from antioxidant of bamboo leaves (AOB) in rats
Authors: Zhang Yu , Tie Xiaowei , Bao Bili , Wu Xiaoqin , Zhang Ying
Published: February 2007

The metabolism of flavoneC-glucosides andp-coumaric acid from antioxidant of bamboo leaves (AOB) in rats is discussed systematically in the present study. Following single oral administration of AOB,p-coumaric acid was detected in plasma but not in gastrointestinal tract extracts and faeces, and the corresponding absorption pharmacokinetic curve at different time points showed a prolonged elimination phase withp-coumaric acid being detected in the kidneys and excreted as its original form (1·80 (sd0·24) % and 1·90 (sd0·26) % at 12 and 24 h, respectively). However, the four flavoneC-glucosides orientin, homoorientin, vitexin and isovitexin were poorly absorbed in the gastrointestinal tract. More than 50 % recovery of flavoneC-glucosides was determined at 12 h and faeces containing these four analytes (21·23 (sd1·92) %) were excreted at 24 h. These data suggested that the effective time these compounds were in the colon was long enough so that they could exert their antioxidant activity and scavenge free radicals. Besides the excretion of the original forms, moieties of the flavoneC-glucosides were hydrolysed by deglycosylation and the opening of the heterocyclic C ring. Some small molecules such as phloroglucinol (PG), hydrocaffeic acid (HCA) and phloretic acid (PA) were detected and identified as metabolites of the flavoneC-glucosides. In the present work, we compared the metabolic fate of flavoneC-glucosides to that of flavoneO-glucosides in rats, and evaluated the absorption, tissue distribution and excretion of flavoneC-glucosides in AOB on their metabolism for the first time.
Six months supplementation with conjugated linoleic acid induces regional-specific fat mass decreases in overweight and obese
Authors: Gaullier Jean-Michel , Halse Johan , Høivik Hans Olav , Høye Kjetil , Syvertsen Christian , Nurminiemi Minna , Hassfeld Cecilie , Einerhand Alexandra , O'Shea Marianne , Gudmundsen Ola
Published: February 2007

Long-term supplementation with conjugated linoleic acid (CLA) reduces body fat mass (BFM) and increases or maintains lean body mass (LBM). However, the regional effect of CLA was not studied. The study aimed to evaluate the effect of CLA per region and safety in healthy, overweight and obese adults. A total of 118 subjects (BMI: 28–32 kg/m2) were included in a double blind, placebo-controlled trial. Subjects were randomised into two groups supplemented with either 3·4 g/d CLA or placebo for 6 months. CLA significantly decreased BFM at month 3 (Δ = − 0·9 %, P = 0·016) and at month 6 (Δ = − 3·4 %, P = 0·043) compared with placebo. The reduction in fat mass was located mostly in the legs (Δ = − 0·8 kg, P < 0·001), and in women (Δ = − 1·3 kg, P = 0·046) with BMI >30 kg/m2 (Δ = − 1·9 kg, P = 0·011), compared with placebo. The waist–hip ratio decreased significantly (P = 0·043) compared with placebo. LBM increased (Δ = +0·5 kg, P = 0·049) within the CLA group. Bone mineral content was not affected (P = 0·70). All changes were independent of diet and physical exercise. Safety parameters including blood lipids, inflammatory and diabetogenic markers remained within the normal range. Adverse events did not differ between the groups. It is concluded that supplementation with CLA in healthy, overweight and obese adults decreases BFM in specific regions and is well tolerated.
Money as tool, money as drug: The biological psychology of a strong incentive
Authors: Lea Stephen E. G. , Webley Paul
Published: February 2007

Why are people interested in money? Specifically, what could be the biological basis for the extraordinary incentive and reinforcing power of money, which seems to be unique to the human species? We identify two ways in which a commodity which is of no biological significance in itself can become a strong motivator. The first is if it is used as a tool, and by a metaphorical extension this is often applied to money: it is used instrumentally, in order to obtain biologically relevant incentives. Second, substances can be strong motivators because they imitate the action of natural incentives but do not produce the fitness gains for which those incentives are instinctively sought. The classic examples of this process are psychoactive drugs, but we argue that the drug concept can also be extended metaphorically to provide an account of money motivation. From a review of theoretical and empirical literature about money, we conclude that (i) there are a number of phenomena that cannot be accounted for by a pure Tool Theory of money motivation; (ii) supplementing Tool Theory with a Drug Theory enables the anomalous phenomena to be explained; and (iii) the human instincts that, according to a Drug Theory, money parasitizes include trading (derived from reciprocal altruism) and object play.
What we need is better theory, not more data
Authors: Anderson Mike
Published: February 2007

Although I find Blair's case for arguing for the distinction between fluid cognitive functions and general intelligence less than compelling, I believe him. However, I also believe that what is required next is a theory of both general intelligence and fluid cognitive functions that articulates the distinction. In the absence of this, more data, particularly of the neuroscience variety, is likely to stall rather than advance progress.
The biology of the interest in money
Authors: Agassi Joseph
Published: February 2007

Why are people interested in money? This question is too broad: there are many kinds of money, interest, and people. The biological approach of Lea & Webley (L&W) makes them seek the roots of this interest, and they contend that tool making and addiction qualify as the roots. Curiosity and the quest for power, however, qualify too. As L&W rightly admit, other approaches supplement their biological one.
The desire to obtain money: A culturally ritualised expression of the aggressive instinct
Authors: Behrendt Ralf-Peter
Published: February 2007

Social behaviour is but an expression of instinctive mechanisms whereby the aggressive instinct is of particular importance, having given rise to most of the complexity of social behaviour through processes of phylogenetic and cultural ritualisation. The role of the aggressive instinct is to dynamically maintain the ranking order in a group, and much of social interaction is concerned with this, including monetary exchange.

What is certain, is that with the elimination of aggression, … the tackling of a task or problem, the self-respect [in] everything that a man does from morning till evening, from the morning shave to the sublimest artistic or scientific creation, would lose all impetus; everything associated with ambition, ranking order, and countless other equally indispensable behaviour patterns would probably also disappear from human life.

— Konrad Lorenz (1963/2002, p. 269)
The evolution of computation in brain circuitry
Authors: Granger Richard
Published: February 2007

The attempt to derive mental function from brain structure is highly constrained by study of the allometric changes among brain components with evolution. In particular, even if homologous structures in different species produce similar computations, they may be constituents of larger systems (e.g., cortical-subcortical loops) that exhibit different composite operations as a function of relative size and connectivity in different-sized brains. The resulting evolutionary constraints set useful and specific conditions on candidate hypotheses of brain circuit computation.
Compassion as an antidote to cruelty
Authors: Fox Michael Allen
Published: February 2007

The impulse toward violence and cruelty is endemic to the human species. But so, likewise, is the impulse toward compassionate behavior. Victor Nell acknowledges this, but he does not explore the matter any further. I supplement his account by discussing how compassion, specifically in the moral education of children, can help remedy the problem of violence and cruelty in society.
Principles of brain connectivity organization
Authors: Hilgetag Claus C.
Published: February 2007

Increases of absolute brain size during evolution reinforced stronger structuring of brain connectivity. One consequence is the hierarchical cluster structure of neural systems that combines predominantly short, but not strictly minimal, wiring with short processing pathways. Principles of “large equals well-connected” and “minimal wiring” do not completely account for observed patterns of brain connectivity. A structural model promises better predictions.
Cruelty: A dispositional or a situational behavior in man?
Authors: Haritos-Fatouros Mika
Published: February 2007

Presentation of evidence from multiple disciplines is the most impressive feature of Nell's article. I have observations and objections, however, about the following issues: (1) violence as a by-product of cruelty; (2) the equation of animal and human cruelty; (3) social psychological evidence contrary to the biological model; (4) whether prevention of cruelty best arises from predispositional or situational factors.
The evolution of language: Present behavioral evidence for past genetic reprogramming in the human lineage
Authors: Eckhardt Robert B.
Published: February 2007

Language and life history can be related functionally through the study of human ontogeny, thus usefully informing our understanding of several unique aspects of the evolution of species. The operational principles outlined by Locke & Bogin (L&B) demonstrate that the present can provide a useful framework for understanding the past.
Metaphysics of money: A special case of emerging autonomy in evolving subsystems
Authors: Glassman Robert B.
Published: February 2007

There is “something more” to money, as this incisive review shows. The target article's shortcoming is its overextension of the “drug” metaphor as a blend of features that do not fit the rationalistic economics and behavioral psychologies summarized as tool theories, but this may be resolved by viewing money as a particular case of the more general evolutionary phenomenon of emergent subsystem autonomy.
The affective neuroeconomics of social brains: One man's cruelty is another's suffering
Authors: Panksepp Jaak
Published: February 2007

Cruelty does not emerge from a single emotional system of the brain. Its many cognitive aspects are intermeshed inextricably with the nature of negative affects ranging from fear to suffering. The rewards of cruelty may be counteracted by a variety of neurochemical factors as well as novel social policies.
Comparing the neural blackboard and the temporal synchrony-based SHRUTI architectures
Authors: Shastri Lokendra
Published: February 2007

Contrary to the assertions made in the target article, temporal synchrony, coupled with an appropriate choice of representational primitives, leads to a functionally adequate and neurally plausible architecture that addresses the massiveness of the binding problem, the problem of 2, the problem of variables, and the transformation of activity-based transient representations of events and situations into structure-based persistent encodings of the same.
Can neural models of cognition benefit from the advantages of connectionism?
Authors: Sommer Friedrich T. , Kanerva Pentti
Published: February 2007

Cognitive function certainly poses the biggest challenge for computational neuroscience. As we argue, past efforts to build neural models of cognition (the target article included) had too narrow a focus on implementing rule-based language processing. The problem with these models is that they sacrifice the advantages of connectionism rather than building on them. Recent and more promising approaches for modeling cognition build on the mathematical properties of distributed neural representations. These approaches truly exploit the key advantages of connectionism, that is, the high representational power of distributed neural codes and similarity-based pattern recognition. The architectures for cognitive computing that emerge from these approaches are neural associative memories endowed with additional mapping operations to handle invariances and to form reduced representations of combinatorial structures.
The investigation of neural correlates of monetary reward by using functional neuroimaging techniques
Authors: Mouras Harold
Published: February 2007

Money is a specifically human incentive. However, functional imaging techniques bring striking evidence that neural circuits pertaining to more “natural” addictive and rewarding processes are involved in response to monetary reward. Main results are evoked here, with specific brain responses demonstrated along the different stages of the process.
Nice idea, but is it science?
Authors: Schuster Richard
Published: February 2007

In the target article, human cruelty is linked to intrinsic reinforcement from engaging in the behavior without any recommendations for a research program to validate or test for such reinforcement and its independence from ultimate adaptive outcomes. Suggestions are offered in this commentary for such a program.
Life stages, put in words: Morning, four; noon, two; evening, three?
Authors: Schleidt Wolfgang M.
Published: February 2007

The social function of language, as exemplified by “tonic communication,” is certainly not restricted to our own species. An individual's cognitive mastering of its environment, moreover, is equally essential for understanding the nature of any language. In the absence of comparative data, it is premature to claim that language skills at a particular developmental stage are uniquely human.
Is it language that makes humans intelligent?
Authors: Herwegen Jo Van , Karmiloff-Smith Annette
Published: February 2007

The target article by Locke & Bogin (L&B) focuses on the evolution of language as a communicative tool. They neglect, however, that from infancy onwards humans have the ability to go beyond successful behaviour and to reflect upon language (and other domains of knowledge) as a problem space in its own right. This ability is not found in other species and may well be what makes humans unique.
Cruelty, age, and thanatourism
Authors: Berghe Pierre L. van den
Published: February 2007

Two areas of research for testing Nell's theory are suggested. One is cruelty's seemingly negative correlation with age, which would confirm its linkage with testosterone, sex, and dominance. The other is the special field of leisure activity called thanatourism, that is, the transformation of loci of human horror into tourist attractions.
Antioxidanzien – hilfreich oder schädlich?
Authors: Biesalski
Published: February 2007

Angereicherte und daher oft mit einer besonderen Funktionalität beworbene Lebensmittel werden in zunehmendem Maße angeboten. Dabei erfolgt besonders eine Anreicherung mit Antioxidanzien (Vitamine C, E und Provitamin A). Da die gewählten Dosierungen unterhalb der Empfehlungen liegen und bei verzehrsüblichen Mengen diese auch nur unwesentlich überschritten werden, besteht vom einzelnen Lebensmittel her kein Risiko für den Verbraucher. Auch bei Verzehr mehrerer angereicherter Lebensmittel führt eine Kumulation nicht zu bedenklichen Werten. Allerdings sollten angereicherte Lebensmittel nicht als Ersatz für eine ungesunde Ernährung genommen werden. Hierin liegt viel eher ein Risiko, da meist nur sehr wenige Antioxidanzien im Lebensmittel angereichert sind. In wie weit der Verbraucher einen Nutzen von angereicherten Lebensmitteln hat ist im Falle der Antioxidanzien nicht gesichert.
Low fat und Light-Produkte – Schnee von gestern?
Authors: Stöckli  , Keller
Published: February 2007

Im Gegensatz zum nicht definierten Begriff «light» werden in der Schweiz energiereduzierte Lebensmittel durch die Lebensmittel- und Gebrauchsgegenständeverordnung geregelt. Energievermindert bedeutet, dass der Kaloriengehalt verglichen mit dem Originalprodukt um 30% vermindert ist; energiearm entspricht einer Kalorienreduktion um 50%. Dies darf nicht über eine Einschränkung des Eiweißgehaltes geschehen. Energie- oder fettreduzierte Lebensmittel haben eine wesentliche Bedeutung in unserem Ernährungs-Alltag erreicht. Der Konsum von fettreduzierten Milchprodukten wird in aktuellen Guidelines aus USA als Teil eines umfassenden «gesunden» Lebensstils zur Vermeidung von Diabetes, Hypertonie und atherosklerotischen Komplikationen empfohlen. Der alleinige Konsum von Light-Produkten ist jedoch nicht nachweislich mit verminderter Prävalenz ernährungsabhängiger Erkrankungen wie Obesitas assoziiert.
Pflanzen-Sterole und Stanole – Wissenschaftliche Befunde zur Wirkung und Sicherheit
Authors: Puspa  , Klör
Published: February 2007

Phytosterole und -stanole haben analoge Funktion zum Cholesterin in tierischen Zellen als wichtige strukturelle und funktionelle Bestandteile von pflanzlichen Zellmembranen. Sie finden sich vor allem in Obst und Gemüse, Getreideprodukten, Samen, Nüssen sowie in Pflanzenölen. Phytosterole führen zu einer Senkung des Gesamt- und des LDL-Cholesterins bei Erwachsenen und bei Kindern. Phytosterolester lassen sich beispielsweise in Margarinen integrieren, was breiter angelegte Studien zur Wirksamkeit ermöglichte. Limitierend vor allem beim Einsatz von Phytosterolen in der Sekundärprophylaxe kardiovaskulärer Krankheiten, ist der Mangel an evidenzbasierten Studien, welche zeigen würden, dass harte Endpunkte, wie kardiovaskuläre und totale Mortalität, günstig beeinflusst würden.
Performance Food im Sportbereich
Authors: Niess  , Hipp  , Thoma  , Striegel
Published: February 2007

Im Sport zur Anwendung kommendes Performance Food umfasst im weiteren Sinne sowohl gängige Nahrungsmittel als auch Nahrungsergänzungsmittel (NEM). Performance Food wird im Sport häufig mit der Erwartung konsumiert, die sportliche Leistung zu steigern, die Ermüdung zu verzögern oder die Trainingsanpassung zu unterstützen. Allerdings gibt es nur für wenige Substanzen wissenschaftlich abgesicherte Erkenntnisse, welche diese Erwartung rechtfertigen. Für die Mehrzahl der angebotenen NEM konnte dieser Nachweis nicht erbracht werden und einige NEM können auch unerwünschte Effekte ausüben. Diese Arbeit soll einen Überblick über die häufiger im Sport zur Anwendungen kommenden Nahrungsmittel und NEM geben und beleuchtet die Thematik speziell hinsichtlich von Effekten auf die sportliche Leistung und Leistungsentwicklung.
Duplex ultrasound investigation of the veins in chronic venous disease of the lower limbs-UIP consensus document. Part I. Basic principles
Authors: Coleridge-Smith  , Labropoulos  , Partsch  , Myers  , Nicolaides  , Cavezzi
Published: February 2007

Background: Duplex ultrasound investigation has become the reference standard in assessing the morphology and haemodynamics of the lower limb veins. The project described in this paper was an initiative of the Union Internationale de Phlébologie (UIP). The aim was to obtain a consensus of international experts on the methodology to be used for assessment of veins in the lower limb by ultrasound imaging. Methods: The authors invited a group of experts from a wide range of countries to participate in this project. Electronic submissions from the experts were made available to all participants via the UIP website. The authors prepared a draft document for discussion at an UIP Chapter meeting held in San Diego, USA in August 2003. Following this meeting a revised manuscript was circulated to all participants and further comments were received by the authors and included in subsequent versions of the manuscript. Eventually all participants agreed the final version of the paper. Results: The experts have made detailed recommendations concerning the methods to be used for duplex ultrasound examination as well as the interpretation of images and measurements obtained. This document suggests a methodology for complete assessment of the superficial and perforating veins of the lower limbs, including recommendations on reporting results and training of personnel involved in these investigations. Conclusions: The authors and a large group of experts have agreed a methodology for the investigation of the lower limbs venous system by duplex ultrasonography.
Why bury ocean bottom seismometers?
Authors: Duennebier Fred K. , Sutton George H.
Published: February 2007

Theory, testing, and use of ocean bottom seismic sensors show that the fidelity of data, particularly measurements of horizontal motion, can be severely distorted and noisy because of mechanical interactions between the sensor package, the ocean bottom, and the ocean water. This lack of fidelity is common, particularly for instruments with large cross sections in the water. These problems should be minimized by burial of the seismic package below the ocean‐sediment interface. To test this hypothesis, two identical seismic packages were operated on the shallow ocean floor within meters of each other with a real‐time connection to land. The packages were configured in a variety of ways, with both packages buried in the sediment, one buried and one on the bottom, and one on a circular 1‐m‐diameter plate and the other buried or on the ocean floor. The resulting data are compared with data from both packages resting on a stable cement slab in the frequency range from 0.2 Hz to above 20 Hz. Data show convincingly that burial of seismic sensors in soft sediment greatly increases data fidelity over sensors placed on the bottom or on a plate on the bottom. While vertical sensors provide reasonable fidelity in most situations, the horizontal data are consistently reliable only when the sensor packages are buried.
Crustal structure of the northwestern Basin and Range Province and its transition to unextended volcanic plateaus
Authors: Lerch D. W. , Klemperer S. L. , Glen J. M. G. , Ponce D. A. , Miller E. L. , Colgan J. P.
Published: February 2007

The northwestern margin of the Basin and Range Province is characterized by a transition from low‐magnitude (∼20%) extension in northwestern Nevada to relatively unextended volcanic plateaus in northeastern California. Seismic‐velocity and potential‐field modeling provides new control on the Mesozoic‐to‐present tectonic evolution of this poorly understood portion of the U.S. Cordillera. We document ∼20% crustal thinning associated with Basin and Range extension from a crustal thickness of ∼37 km under northeastern California to ∼31 km under northwestern Nevada that is consistent with the amount of extension recorded in the upper crust in northwestern Nevada, suggesting the crustal response to extension was relatively homogeneous over the entire crustal column. Our modeling also shows a well‐defined, 80‐km‐wide zone of unusually low upper‐crustal velocities (∼5.9–6.1 km/s) that coincide with the surface location of sparse Cretaceous granites, locating the elusive northern extension of the Sierra Nevada batholith through northwestern Nevada for the first time in the subsurface. Combining geological and geophysical data, we reconstruct the late Cretaceous‐to‐present crustal evolution of this region, documenting an interplay between magmatic addition to the crust, erosional exhumation, sedimentation, and extension that has reversed the direction of crustal thinning from a west‐facing continental margin to an east‐facing interior basin margin over this time interval. Finally, we find no evidence in northwestern Nevada for unusually thick crust (>40 km) prior to Basin and Range extension.
Tropospheric vertical distribution of tropical Atlantic ozone observed by TES during the northern African biomass burning season
Authors: Jourdain L. , Worden H. M. , Worden J. R. , Bowman K. , Li Q. , Eldering A. , Kulawik S. S. , Osterman G. , Boersma K. F. , Fisher B. , Rinsland C. P. , Beer R. , Gunson M.
Published: February 2007

We present vertical distributions of ozone from the Tropospheric Emission Spectrometer (TES) over the tropical Atlantic Ocean during January 2005. Between 10N and 20S, TES ozone retrievals have Degrees of Freedom for signal (DOF) around 0.7–0.8 each for tropospheric altitudes above and below 500 hPa. As a result, TES is able to capture for the first time from space a distribution characterized by two maxima: one in the lower troposphere north of the ITCZ and one in the middle and upper troposphere south of the ITCZ. We focus our analysis on the north tropical Atlantic Ocean, where most of previous satellite observations showed discrepancies with in‐situ ozone observations and models. Trajectory analyses and a sensitivity study using the GEOS‐Chem model confirm the influence of northern Africa biomass burning on the elevated ozone mixing ratios observed by TES over this region.
Retrieval of reflections from seismic background‐noise measurements
Authors: Draganov Deyan , Wapenaar Kees , Mulder Wim , Singer Johannes , Verdel Arie
Published: February 2007

The retrieval of the earth's reflection response from cross‐correlations of seismic noise recordings can provide valuable information, which may otherwise not be available due to limited spatial distribution of seismic sources. We cross‐correlated ten hours of seismic background‐noise data acquired in a desert area. The cross‐correlation results show several coherent events, which align very well with reflections from an active survey at the same location. Therefore, we interpret these coherent events as reflections. Retrieving seismic reflections from background‐noise measurements has a wide range of applications in regional seismology, frontier exploration and long‐term monitoring of processes in the earth's subsurface.
Halocarbons in the atmosphere of the industrial‐related Pearl River Delta region of China
Authors: Chan L. Y. , Chu K. W.
Published: February 2007

In a study conducted in 2000, 19 halocarbons from 78 canister air samples were measured in five industrial cities in the Pearl River Delta (PRD), one of the fastest growing industrial regions in China. Preliminary year 2000 halocarbon levels have been derived using available data and information. Comparisons have been made between the data obtained in this study and the corresponding estimated global/tropical surface mixing ratios obtained from the literature. With the exception of CFC‐114 and halon‐2402, the halocarbons had significant enhancements, presumably due to their recent increased production and extensive industrial uses. In contrast to the small enhancements (<7%) for two chlorofluorocarbons (CFC‐11 and CFC‐12), large enhancements (>30%) for three HCFC replacements (HCFC‐22, ‐141b, ‐142b) were observed. In general, HCFCs have virtually replaced CFCs, except for some localized usage. The median of HFC‐134a also had a 36% enhancement; however, 23% of the samples were near or at the global background level. These contradictory results could not give a clear situation of uses of this new chemical in the region. Our data also indicate that halocarbon‐based cleaning solvents, including CFC‐113, methyl chloroform, trichloroethene and tetrachloroethene, were still frequently used in PRD industries. High mixing ratios of these halogenated solvents were frequently measured in Dongguan, a city with light industry. Higher atmospheric levels of the three methyl halides (−Cl, −Br, and −I) were found in a coastal city, Jiangmen. These may be contributed to by industrial emissions and coastal terrestrial and coastal seawater sources.
Surface fluxes of Si and C adatoms at initial growth stages of SiC quantum dots
Authors: Rider A. E. , Levchenko I. , Ostrikov K.
Published: February 2007

Self-assembly of highly stoichiometric SiC quantum dots still remains a major challenge for the gas/plasma-based nanodot synthesis. By means of a multiscale hybrid numerical simulation of the initial stage (0.1–2.5 s into the process) of deposition of SiC∕Si(100)quantum dot nuclei, it is shown that equal Si and kst atom deposition fluxes result in strong nonstoichiometric nanodot composition due to very different surface fluxes of Si and C adatoms to the quantum dots. At this stage, the surface fluxes of Si and C adatoms to SiC nanodots can be effectively controlled by manipulating the Si∕C atom influx ratio and the Si(100)surface temperature. It is demonstrated that at a surface temperature of 800 K the surface fluxes can be equalized after only 0.05 s into the process; however, it takes more then 1 s at a surface temperature of 600 K. Based on the results of this study, effective strategies to maintain a stoichiometric ([Si]∕[C]=1:1) elemental ratio during the initial stages of deposition of SiC∕Si(100) quantum dot nuclei in a neutral/ionized gas-based process are proposed.
Neutron production and implosion characteristics of a deuterium gas-puff Z pinch
Authors: Coverdale C. A. , Deeney C. , Velikovich A. L. , Clark R. W. , Chong Y. K. , Davis J. , Chittenden J. , Ruiz C. L. , Cooper G. W. , Nelson A. J. , Franklin J. , LePell P. D. , Apruzese J. P. , Levine J. , Banister J. , Qi N.
Published: February 2007

Experiments on the Z accelerator with deuterium gas puff implosions have produced up to 3.9×1013(±20%) neutrons at 2.34 MeV (±0.10MeV). Experimentally, the mechanism for generating these neutrons has not been definitively identified through isotropy measurements, but activation diagnostics suggest multiple mechanisms may be responsible. One-, two-, and three-dimensional magnetohydrodynamic (MHD) calculations have indicated that thermonuclear outputs from Z could be expected to be in the (0.3–1.0)×1014 range. X-ray diagnostics of plasma conditions, fielded to look at dopant materials in the deuterium, have shown that the stagnated deuterium plasma achieved electron temperatures of 2.2keV and ion densities of 2×1020cm−3, in agreement with the MHD calculations.
Cathodoluminescence and room temperature ferromagnetism of Mn-doped ZnO nanorod arrays grown by chemical vapor deposition
Authors: Yan H. L. , Zhong X. L. , Wang J. B. , Huang G. J. , Ding S. L. , Zhou G. C. , Zhou Y. C.
Published: February 2007

Mn-doped ZnO nanorods are prepared by a chemical vapor deposition method using zinc and MnO2 powders as source materials of Zn and Mn, respectively. Cathodoluminescence (CL) characterization indicates that the Mn-doped ZnO nanorods grown at different growth temperatures have different oxygen vacancy concentrations. Room temperature ferromagnetism with a saturation magnetization of 0.87μB∕Mn has been observed in Mn-doped ZnO nanorods grown at 650°C, in which moderate oxygen vacancy concentration is observed by CL characterization. It is also found that oxygen vacancies play an important role in the appearance of room temperature ferromagnetism in Mn-doped ZnO nanorods.
Tuning the resonant frequency of single-walled carbon nanotube bundle oscillators through electron-beam-induced cross-link formations
Authors: Jaroenapibal P. , Luzzi D. E. , Evoy S.
Published: February 2007

The authors investigate the effect of electron irradiation on the resonant frequency of single-walled carbon nanotube bundles. Electron beam irradiation was employed to induce the formation of intertube cross-linking. An increase in the resonant frequency was observed at low electron doses as the bending modulus was enhanced by cross-link formation. Higher doses induced amorphization and knock-on damage in the bundle, resulting in an overall reduction of the bending modulus. The effect of stiffness enhancement is more pronounced in larger diameter bundles due to the more compliant initial condition. At 45nm diameter, an increase in bending modulus of 115% is observed.
Effect of attractions on the structure of polymer solutions confined between surfaces: A density functional approach
Authors: Patra Chandra N.
Published: February 2007

A density functional theory is presented to study the effect of attractions on the structure of polymer solutions confined between surfaces. The polymer molecules have been modeled as a pearl necklace of freely jointed hard spheres and the solvent as hard spheres, both having Yukawa-type attractions and the mixture being confined between attractive Yukawa-type surfaces. The present theory treats the ideal gas free energy functional exactly and uses weighted density approximation for the hard chain and hard sphere contributions to the excess free energy functional. The attractive interactions are calculated using the direct correlation function obtained from the polymer reference interaction site model theory along with the mean spherical approximation closure. The theoretical predictions on the density profiles of the polymer and the solvent molecules are found to agree quite well with the Monte Carlo simulation results for varying densities, chain lengths, wall separations, and different sets of interaction potentials.
Efficient photovoltaic cells with wide photosensitization range fabricated from rhenium benzathiazole complexes
Authors: Wong Hei Ling , Mak Chris S. K. , Chan Wai Kin , Djurišić Aleksandra B.
Published: February 2007

Bulk heterojunction ITO/CuPc/sensitizer:C60∕C60∕Al (ITO denotes indium tin oxide; CuPc denotes copper phthalocyanine) photovoltaic cells were fabricated by using rhenium(I) complexes with benzathiazole ligands as the sensitizers. The complexes enhance the photosensitivity in the region of 450–550nm in which CuPc and C60 have little absorption. The devices exhibited high fill factors in excess of 0.6, and the power conversion efficiency of the best device 1.72%. A device based on pure CuPc:C60 mixed layer was fabricated for comparison. The external quantum efficiency of the devices remained higher than 10% in the entire visible region, which clearly demonstrated the importance of rhenium complexes as sensitizers.
Polymorphism in pentacene thin films on SiO2 substrate
Authors: Kakudate Toshiyuki , Yoshimoto Noriyuki , Saito Yoshio
Published: February 2007

The polymorphism of pentacene thin films on SiO2 substrate was investigated by grazing incidence x-ray diffractometry (GIXD). The in-plane GIXD patterns were obtained from vacuum deposited ultrathin films. By comparing the in-plane structures with thicker films, it was elucidated that ultrathin films have the same lattice constants as that of films of 100nm thick. Consistency of determined interplanar d11 spacings of the two polymorphs suggests the epitaxial growth that bulk phase grows onto thin-film phase. Considering the obtained unit cell parameters, the mechanism of the transformation between polymorphs was discussed in terms of equilibrium shapes during nucleation process.
Output properties of C60 field-effect transistors with different source/drain electrodes
Authors: Takahashi Nobuya , Maeda Akira , Uno Koichi , Shikoh Eiji , Yamamoto Yoshiyuki , Hori Hidenobu , Kubozono Yoshihiro , Fujiwara Akihiko
Published: February 2007

C 60 field-effect transistors (FETs) have been fabricated with source/drain electrodes of three different materials, indium tin oxide (ITO), Au, and Pt. High field-effect mobility μFE of FETs with ITO electrodes, 1.6×10−1cm2∕Vs, shows that ITO is a potential material for the electrodes of organic electronics. Although the highest Schottky barrier and the lowest μFE were expected, μFE of FET with Pt electrodes (1.4×10−1cm2∕Vs) is higher than that of FET with Au electrodes (9.6×10−2cm2∕Vs). The result suggests that modification of local electronic structure at the interface between electrodes and C60 affects device performance.
Low temperature (<100°C) patterned growth of ZnO nanorod arrays on Si
Authors: Kang B. S. , Pearton S. J. , Ren F.
Published: February 2007

Micropatterned growth of ZnO nanorod arrays on silicon substrates using a low temperature aqueous method is demonstrated. ZnO nanocrystals were used as seeds for producing well-aligned, wurtzite ZnO nanorod arrays with spin coating. The shape of the ZnO nanorods was sensitive to the orientation of substrate as well as the molar composition of the chemical precursors. X-ray diffraction was used to investigate the effect of the substrate orientation on the crystal structure of the patterned grown ZnO nanorod arrays, showing that growth on (100) Si was faster than on (111) Si, with the nanorods growing preferentially in the ⟨001⟩ direction. Photoluminescence of the patterned ZnO nanorod arrays showed good optical quality with near band-edge emission at 3.24eV, showing the promise of this approach for micropatterned optical device applications using low temperature synthesis and the conventional lithography.
Trigger Factor can antagonize both SecB and DnaK/DnaJ chaperone functions in
Escherichia coli
Authors: Ullers Ronald S. , Ang Debbie , Schwager Françoise , Georgopoulos Costa , Genevaux Pierre
Published: February 2007

Polypeptides emerging from the ribosome are assisted by a pool of molecular chaperones and targeting factors, which enable them to efficiently partition as cytoplasmic, integral membrane, or exported proteins. In
Escherichia coli
, the chaperones SecB, Trigger Factor (TF), and DnaK are key players in this process. Here, we report that, as with
dnaK
or
dnaJ
mutants, a
secB
null strain exhibits a strong cold-sensitive (Cs) phenotype. Through suppressor analyses, we found that inactivating mutations in the
tig
gene encoding TF fully relieve both the Cs phenotype and protein aggregation observed in the absence of SecB. This antagonistic effect of TF depends on its ribosome-binding and chaperone activities but unrelated to its peptidyl-prolyl
cis/trans
isomerase (PPIase) activity. Furthermore, in contrast to the previously known synergistic action of TF and DnaK/DnaJ above 30°C, a
tig
null mutation partially suppresses the Cs phenotype exhibited by a compromised DnaK/DnaJ chaperone machine. The antagonistic role of TF is further exemplified by the fact that the
secB dnaJ
double mutant is viable only in the absence of TF. Finally, we show that, in the absence of TF, more SecA and ribosomes are associated with the inner membrane, suggesting that the presence of TF directly or indirectly interferes with the process of cotranslational protein targeting to the Sec translocon.
HIV-1 gp120 inhibits TLR9-mediated activation and IFN-α secretion in plasmacytoid dendritic cells
Authors: Martinelli Elena , Cicala Claudia , Van Ryk Donald , Goode Diana J. , Macleod Katilyn , Arthos James , Fauci Anthony S.
Published: February 2007

Plasmacytoid dendritic cells (pDCs) play a central role in innate and adaptive immune responses against viral infections. pDCs secrete type I IFNs and proinflammatory cytokines upon stimulation by either TLR7 or TLR9. Throughout the course of HIV infection, the production of type-I IFNs is profoundly impaired, and total pDC cell counts in peripheral blood correlates inversely with viral load and positively with CD4+T cell count. The origin of these defects is unclear. pDCs express CD4, CCR5, and CXCR4, the primary receptor and coreceptors, respectively, for the HIV envelope; yet little is known concerning the effects of the viral envelope on these cells. Here, we show that exposure of pDCs to gp120 results in the suppression of activation of these cells. This suppression is specific for TLR9-mediated responses, because TLR7-mediated responses are unaffected by gp120. gp120 also suppressed TLR9-mediated induction of proinflammatory cytokines and expression of CD83, a marker of DC activation. Finally, gp120 suppressed pDC-induced cytolytic activity of natural killer cells. Taken together, these data demonstrate that the direct interaction of HIV-1 gp120 with pDCs interferes with TLR9 activation resulting in a decreased ability of pDCs to secrete antiviral and inflammatory factors that play a central role in initiating host immune responses against invading pathogens.
The
Nf2
tumor suppressor regulates cell–cell adhesion during tissue fusion
Authors: McLaughlin Margaret E. , Kruger Genevieve M. , Slocum Kelly L. , Crowley Denise , Michaud Norman A. , Huang Jennifer , Magendantz Margaret , Jacks Tyler
Published: February 2007

Tissue fusion, the morphogenic process by which epithelial sheets are drawn together and sealed, has been extensively studied in
Drosophila
. However, there are unique features of mammalian tissue fusion that remain poorly understood. Notably, detachment and apoptosis occur at the leading front in mammals but not in invertebrates. We found that in the mouse embryo, expression of the
Nf2
tumor suppressor, merlin, is dynamically regulated during tissue fusion:
Nf2
expression is low at the leading front before fusion and high across the fused tissue bridge. Mosaic
Nf2
mutants exhibit a global defect in tissue fusion characterized by ectopic detachment and increased detachment-induced apoptosis (anoikis). By contrast with core components of the junctional complex, we find that merlin is required specifically for the assembly but not the maintenance of the junctional complex. Our work reveals that regulation of
Nf2
expression is a previously unrecognized means of controlling adhesion at the leading front, thereby ensuring successful tissue fusion.
Defects in lamin B1 expression or processing affect interphase chromosome position and gene expression
Authors: Malhas Ashraf , Lee Chiu Fan , Sanders Rebecca , Saunders Nigel J. , Vaux David J.
Published: February 2007

Radial organization of nuclei with peripheral gene-poor chromosomes and central gene-rich chromosomes is common and could depend on the nuclear boundary as a scaffold or position marker. To test this, we studied the role of the ubiquitous nuclear envelope (NE) component lamin B1 in NE stability, chromosome territory position, and gene expression. The stability of the lamin B1 lamina is dependent on lamin endoproteolysis (by Rce1) but not carboxymethylation (by Icmt), whereas lamin C lamina stability is not affected by the loss of full-length lamin B1 or its processing. Comparison of wild-type murine fibroblasts with fibroblasts lacking full-length lamin B1, or defective in CAAX processing, identified genes that depend on a stable processed lamin B1 lamina for normal expression. We also demonstrate that the position of mouse chromosome 18 but not 19 is dependent on such a stable nuclear lamina. The results implicate processed lamin B1 in the control of gene expression as well as chromosome position.
Catch me if you can! Oxidative protein trapping in the intermembrane space of mitochondria
Authors: Herrmann Johannes M. , Köhl Roman
Published: February 2007

The intermembrane space (IMS) of mitochondria, the compartment that phylogenetically originated from the periplasm of bacteria, contains machinery to catalyze the oxidative folding of proteins (Mesecke, N., N. Terziyska, C. Kozany, F. Baumann, W. Neupert, K. Hell, and J.M. Herrmann. 2005. Cell. 121:1059–1069; Rissler, M., N. Wiedemann, S. Pfannschmidt, K. Gabriel, B. Guiard, N. Pfanner, and A. Chacinska. 2005. J. Mol. Biol. 353: 485–492; Tokatlidis, K. 2005. Cell. 121:965–96). This machinery introduces disulfide bonds into newly imported precursor proteins, thereby locking them in a folded conformation. Because folded proteins cannot traverse the translocase of the outer membrane, this stably traps the proteins in the mitochondria. The principle of protein oxidation in the IMS presumably has been conserved from the bacterial periplasm and has been adapted during evolution to drive the vectorial translocation of proteins from the cytosol into the mitochondria.
Complex genetic control of susceptibility to malaria: positional cloning of the Char9 locus
Authors: Min-Oo Gundula , Fortin Anny , Pitari Giuseppina , Tam Mifong , Stevenson Mary M. , Gros Philippe
Published: February 2007

Mouse strains AcB55 and AcB61 are resistant to malaria by virtue of a mutation in erythrocyte pyruvate kinase (PklrI90N). Linkage analysis in [AcB55 × A/J] F2 mice detected a second locus (Char9; logarithm of odds = 4.74) that regulates the blood-stage replication of Plasmodium chabaudi AS independently of Pklr. We characterized the 77 genes of the Char9 locus for tissue-specific expression, strain-specific alterations in gene expression, and polymorphic variants that are possibly associated with differential susceptibility. We identified Vnn1/Vnn3 as the likely candidates responsible for Char9. Vnn3/Vnn1 map within a conserved haplotype block and show expression levels that are strictly cis-regulated by this haplotype. The absence of Vnn messenger RNA expression and lack of pantetheinase protein activity in tissues are associated with susceptibility to malaria and are linked to a complex rearrangement in the Vnn3 promoter region. The A/J strain also carries a unique nonsense mutation that leads to a truncated protein. Vanin genes code for a pantetheinase involved in the production of cysteamine, a key regulator of host responses to inflammatory stimuli. Administration of cystamine in vivo partially corrects susceptibility to malaria in A/J mice, as measured by reduced blood parasitemia and decreased mortality. These studies suggest that pantetheinase is critical for the host response to malaria.
Closed manifolds coming from Artinian complete intersections
Authors: Papadima Ştefan , Păunescu Laurenţiu
Published: February 2007

We reformulate the integrality property of the Poincaré inner product in the middle dimension, for an arbitrary Poincaré

Q

\mathbb {Q}

-algebra, in classical terms (discriminant and local invariants). When the algebra is

1
1

-connected, we show that this property is the only obstruction to realizing it by a smooth closed manifold, in dimension

8
8

. We analyse the homogeneous artinian complete intersections over

Q

\mathbb {Q}

realized by smooth closed manifolds of dimension

8
8

, and their signatures.
Projectivity and freeness over comodule algebras
Authors: Skryabin Serge
Published: February 2007

Let

H
H

be a Hopf algebra and

A
A

an

H
H

-simple right

H
H

-comodule algebra. It is shown that under certain hypotheses every

(
H
,
A
)

(H,A)

-Hopf module is either projective or free as an

A
A

-module and

A
A

is either a quasi-Frobenius or a semisimple ring. As an application it is proved that every weakly finite (in particular, every finite dimensional) Hopf algebra is free both as a left and a right module over its finite dimensional right coideal subalgebras, and the latter are Frobenius algebras. Similar results are obtained for

H
H

-simple

H
H

-module algebras.
Classifying representations by way of Grassmannians
Authors: Huisgen-Zimmermann Birge
Published: February 2007

Let

Λ
\Lambda

be a finite-dimensional algebra over an algebraically closed field. Criteria are given which characterize existence of a fine or coarse moduli space classifying, up to isomorphism, the representations of

Λ
\Lambda

with fixed dimension

d
d

and fixed squarefree top

T
T

. Next to providing a complete theoretical picture, some of these equivalent conditions are readily checkable from quiver and relations of

Λ
\Lambda

. In the case of existence of a moduli space—unexpectedly frequent in light of the stringency of fine classification—this space is always projective and, in fact, arises as a closed subvariety

G
r
a
s
s

d
T

\operatorname {\mathfrak {Grass}}^T_d

of a classical Grassmannian. Even when the full moduli problem fails to be solvable, the variety

G
r
a
s
s

d
T

\operatorname {\mathfrak {Grass}}^T_d

is seen to have distinctive properties recommending it as a substitute for a moduli space. As an application, a characterization of the algebras having only finitely many representations with fixed simple top is obtained; in this case of ‘finite local representation type at a given simple

T
T

’, the radical layering

(

J

l

M

/

J

l
+
1

M

)

l
≥
0

\bigl ( J^{l}M/ J^{l+1}M \bigr )_{l \ge 0}

is shown to be a classifying invariant for the modules with top

T
T

. This relies on the following general fact obtained as a byproduct: proper degenerations of a local module

M
M

never have the same radical layering as

M
M

.
A uniqueness theorem for the singly periodic genus-one helicoid
Authors: Alarcón Antonio , Ferrer Leonor , Martín Francisco
Published: February 2007

The singly periodic genus-one helicoid was in the origin of the discovery of the first example of a complete minimal surface with finite topology but infinite total curvature, the celebrated Hoffman-Karcher-Wei’s genus one helicoid. The objective of this paper is to give a uniqueness theorem for the singly periodic genus-one helicoid provided the existence of one symmetry.