bluuebunny/crossref_metadata_2025 huggingface dataset:
The Catalytic Conversion of Thiophenes over Large H‐ZSM‐5 Crystals: An X‐Ray, UV/Vis, and Fluorescence Microspectroscopic Study
Authors: Kox Marianne H. F. , Mijovilovich Ana , Sättler Jesper J. H. B. , Stavitski Eli , Weckhuysen Bert M.
Published: April 2010

X‐ray absorption, UV/Vis, and fluorescence microspectroscopy have been used to characterize the catalytic conversion of thiophene derivatives within the micropores of an individual H‐ZSM‐5 zeolite crystal. Space‐resolved information into the Si/Al ratios and sulfur content was provided by X‐ray absorption microspectroscopy. X‐ray absorption near‐edge spectroscopy spectral information and modeling indicated the presence of a sulfur atom, in close proximity of two oxygen atoms, that is, at approximately 2.5 Å. Space‐resolved spectroscopic measurements provided experimental evidence for the formation of conjugated carbocationic reaction intermediates by opening of the thiophene ring. The molecular alignment of reaction products within the straight pores of the individual H‐ZSM‐5 zeolite crystals was observed with polarized light UV/Vis microspectroscopy. In addition, confocal fluorescence microscopy revealed the 3D distribution of different reaction products and demonstrated the influence of the H‐ZSM‐5 crystal’s intergrowth structure and its related molecular diffusion barriers.
Formation of Furfural in Catalytic Transformation of Levoglucosan over Mesoporous Materials
Authors: Käldström M. , Kumar N. , Heikkilä T. , Tiitta M. , Salmi T. , Murzin D. Yu.
Published: April 2010

Catalytic transformations of levoglucosan (1‐6‐anhydro‐β‐D‐glucopyranose) and furfural were carried out in a fixed‐bed reactor at 573 K over mesoporous materials. Proton forms of MCM‐41, MCM‐48, SBA‐15, and platinum form of MCM‐48 catalysts were tested in the reaction, whereas H‐Beta and quartz sand were used as reference materials. The yield of the transformation products was substantially influenced by the catalyst structures. Oxygenated species were the main liquid products, consisting mainly of aldehydes and furfural. The formation of furfural was the highest over MCM‐41 catalyst followed by SBA‐15, MCM‐48, and H‐Beta catalyst. All catalysts were to some extent deactivated due to coke formation. However, it was possible to successfully regenerate the spent catalysts without changing the structure.
Culture Conditions and Investigation of Bioreactor Configurations for Lipase Production by Rhizopus oryzae
Authors: López E. , Deive F. J. , Longo M. A. , Sanromán M. Á.
Published: April 2010

Lipolytic enzymes are the subject of great industrial and academic interest. For this reason, a detailed study of lipolytic enzyme production by the fungus Rhizopus oryzae is tackled, and several steps from plate to shake flasks and bioreactor cultures are investigated in order to propose an optimized strategy to perform the biological process. The suitability of several lipidic compounds and surfactants is assessed. Triton X‐100 (5 g/L) gives the highest activities with a maximum value of 6320 U/L which is 10‐fold the value attained in cultures without addition of lipidic compounds. As there are almost no studies on bench‐scale bioreactors, two bioreactor configurations, stirred tank and air‐lift, are investigated to determine the most suitable one to carry out the biological reaction. It is demonstrated that the lipolytic activity is strongly enhanced when a stirred‐tank bioreactor is used with a maximum value of 3521 U/L within two days which is clearly higher than the values produced by other recently reported species.
Reversible Coordination of Dioxygen by Tripodal Tetraamine Copper Complexes Incorporated in a Porous Silica Framework
Authors: Suspène Clément , Brandès Stéphane , Guilard Roger
Published: April 2010

The present study reports the synthesis and rational design of porous structured materials by using a templating method. A tetraethoxysilylated tripodal tetraamine (TREN) was covalently incorporated in a silica framework with a double imprint: A surfactant template and a metal ion imprint. The presence of a cationic surfactant (CTAB) endowed the material with a high porosity, and the tripodal or square‐pyramidal topology of the ligand was preserved thanks to the use of the silylated CuII complex. After removal of the surfactant and de‐metalation, the incorporated tetraamine was quantitatively complexed by CuCl2 and the material has shown after thermal activation that a reversible binding of O2 on the metal ions occurred. This chemisorption process was monitored by UV/Vis and EPR spectroscopies, and the Cu:O2 adduct was postulated to be an end‐on μ‐η1:η1‐peroxodicopper(II) complex bridged by a chloride ion. The CuI‐active species, formed during the activation step, were fully recovered during several O2 binding cycles. The high reactivity of the copper complexes and the room‐temperature stability of the dioxygen adduct were explained by the fine adaptability of the tripodal ligand to different geometries, the confinement of the active sites in the hybrid silica that protect them from degradation by a control of the metal‐ion microenvironment, as well as the short‐range lamellar order of the copper complexes in the framework.
Synthesis of Symmetrical Multichromophoric Bodipy Dyes and Their Facile Transformation into Energy Transfer Cassettes
Authors: Bozdemir O. Altan , Cakmak Yusuf , Sozmen Fazli , Ozdemir Tugba , Siemiarczuk Aleksander , Akkaya Engin U.
Published: April 2010

Multichromophoric boron‐dipyrromethene (Bodipy) dyes synthesized on phenylene‐ethynylene platforms have been be converted to energy transfer cassettes in a one‐step chemical transformation. Excitation energy transfer processes in these highly symmetrical derivatives were studied in detail, including time‐resolved fluorescence spectroscopy techniques. Excitation spectra and the emission lifetimes suggest efficient energy transfer between the donor and acceptor chromophore. These novel energy transfer cassettes, while highlighting a short‐cut approach to similar energy transfer systems, could be useful as large pseudo‐Stokes shift multichromophoric dyes with potential applications in diverse applications.
Magnetically Recoverable Core–Shell Nanocomposites with Enhanced Photocatalytic Activity
Authors: Ye Miaomiao , Zhang Qiao , Hu Yongxing , Ge Jianping , Lu Zhenda , He Le , Chen Zhonglin , Yin Yadong
Published: April 2010

Core–shell structured Fe3O4/SiO2/TiO2 nanocomposites with enhanced photocatalytic activity that are capable of fast magnetic separation have been successfully synthesized by combining two steps of a sol–gel process with calcination. The as‐obtained core–shell structure is composed of a central magnetite core with a strong response to external fields, an interlayer of SiO2, and an outer layer of TiO2 nanocrystals with a tunable average size. The convenient control over the size and crystallinity of the TiO2 nanocatalysts makes it possible to achieve higher photocatalytic efficiency than that of commercial photocatalyst Degussa P25. The photocatalytic activity increases as the thickness of the TiO2 nanocrystal shell decreases. The presence of SiO2 interlayer helps to enhance the photocatalytic efficiency of the TiO2 nanocrystal shell as well as the chemical and thermal stability of Fe3O4 core. In addition, the TiO2 nanocrystals strongly adhere to the magnetic supports through covalent bonds. We demonstrate that this photocatalyst can be easily recycled by applying an external magnetic field while maintaining their photocatalytic activity during at least eighteen cycles of use.
Remarkably Efficient Photocurrent Generation Based on a [60]Fullerene–Triosmium Cluster/Zn–Porphyrin/Boron–Dipyrrin Triad SAM
Authors: Lee Chang Yeon , Jang Jae Kwon , Kim Chul Hoon , Jung Jaehoon , Park Bo Keun , Park Jihee , Choi Wonyong , Han Young‐Kyu , Joo Taiha , Park Joon T.
Published: April 2010

A new artificial photosynthetic triad array, a [60]fullerene–triosmium cluster/zinc–porphyrin/boron–dipyrrin complex (1, Os3C60/ZnP/Bodipy), has been prepared by decarbonylation of Os3(CO)8(CN(CH2)3Si(OEt)3)(μ3‐η2:η2:η2‐C60) (6) with Me3NO/MeCN and subsequent reaction with the isocyanide ligand CNZnP/Bodipy (5) containing zinc porphyrin (ZnP) and boron dipyrrin (Bodipy) moieties. Triad 1 has been characterized by various spectroscopic methods (MS, NMR, IR, UV/Vis, photoluminescence, and transient absorption spectroscopy). The electrochemical properties of 1 in chlorobenzene (CB) have been examined by cyclic voltammetry; the general feature of the cyclic voltammogram of 1 is nine reversible one‐electron redox couples, that is, the sum of those of 5 and 6. DFT has been applied to study the molecular and electronic structures of 1. On the basis of fluorescence‐lifetime measurements and transient absorption spectroscopic data, 1 undergoes an efficient energy transfer from Bodipy to ZnP and a fast electron transfer from ZnP to C60; the detailed kinetics involved in both events have been elucidated. The SAM of triad 1 (1/ITO; ITO=indium–tin oxide) has been prepared by immersion of an ITO electrode in a CB solution of 1 and diazabicyclo‐octane (2:1 equiv), and characterized by UV/Vis absorption spectroscopy, water contact angle, X‐ray photoelectron spectroscopy, and cyclic voltammetry. The photoelectrochemical properties of 1/ITO have been investigated by a standard three‐electrode system in the presence of an ascorbic acid sacrificial electron donor. The quantum yield of the photoelectrochemical cell has been estimated to be 29 % based on the number of photons absorbed by the chromophores. Our triad 1 is unique when compared to previously reported photoinduced electron‐transfer arrays, in that C60 is linked by π bonding with little perturbation of the C60 electron delocalization.
Mechanistic Study of the Reaction of Thiol‐Containing Enzymes with α,β‐Unsaturated Carbonyl Substrates by Computation and Chemoassays
Authors: Paasche Alexander , Schiller Markus , Schirmeister Tanja , Engels Bernd
Published: April 2010

We investigated the reactions between substituted α,β‐unsaturated carbonyl compounds (Michael systems) and thiols by computations as well as chemoassays. The results give insight into variations in the underlying mechanisms as a function of the substitution pattern. This is of interest for the mechanisms of inhibition of the SARS coronavirus main protease (SARS‐CoV Mpro) by etacrynic acid derivatives as well as for the excess toxicity of substituted α,β‐unsaturated carbonyl compounds. This study compares possible reaction courses including 1,4‐addition followed by a ketonization step, and underscores the importance of a base‐catalyzed step for the reactivity of thiol groups in enzymes. Phenyl and methyl substituents at the Michael system decrease the reactivity of the electrophilic compound, but chlorophenyl substituents partly recover the reactivity. Computations also indicate that electron‐pushing substituents lead to a change in the reaction mechanism. The conformation of the Michael system is also found to significantly influence reactivity: thes‐cisconformation leads to higher reactivity than thes‐transconformation. The computed data explain the trends in measured inhibition potencies of substituted α,β‐unsaturated carbonyl compounds and of reaction rates in chemical assays. They also indicate that the reversibility of inhibition does not stand in contrast to the formation of a new covalent bond between inhibitor and protease.
Triple Phase Boundary Photovoltammetry: Resolving Rhodamine B Reactivity in 4‐(3‐Phenylpropyl)‐Pyridine Microdroplets
Authors: Collins Andrew M. , Zhang Xiaohang , Scragg Jonathan J. , Blanchard Gary J. , Marken Frank
Published: April 2010

Rhodamine B base is employed as a photoactive redox system in a liquid | liquid | electrode triple phase boundary electrochemical experiment. Microdroplets of the water‐immiscible 3‐(4‐phenylpropyl)‐pyridine (PPP) containing rhodamine B are deposited onto a basal plane pyrolytic graphite electrode surface which is then immersed into an aqueous solution containing 0.5 Mphosphate buffer solution (pH 12). In cyclic voltammetry experiments, it is shown that dark reduction of rhodamine B to leuco‐rhodamine B in PPP occurs in two steps—both one electron processes—and the re‐oxidation occurs in a single two‐electron process. Voltammetric signals are consistent with Na+transfer (for the first reduction step) and proton transfer (for the second reduction step) coupled to the electron transfer. A proton‐driven disproportionation reaction (withkdis=3 mol−1 dm3 s−1at pH 12) is observed for the one‐electron reduced intermediate. In the presence of light, a new photocatalysed oxidation process for the two‐electron conversion of leuco‐rhodamine B to rhodamine B is observed. Photoexcitation of rhodamine B is shown to trigger an effective photo‐comproportionation mechanism. Quantitative insights into the dark and photomechanisms are obtained by comparison of rhodamine B and rhodamine B octadecylester and by applying an approximate numerical simulation procedure based on DigiSim.
Investigation on the Second Part of the Electromagnetic SERS Enhancement and Resulting Fabrication Strategies of Anisotropic Plasmonic Arrays
Authors: Cialla Dana , Petschulat Jörg , Hübner Uwe , Schneidewind Henrik , Zeisberger Matthias , Mattheis Roland , Pertsch Thomas , Schmitt Michael , Möller Robert , Popp Jürgen
Published: April 2010

In general, the electromagnetic mechanism is understood as the strongest contribution to the overall surface‐enhanced Raman spectroscopy (SERS) enhancement. Due to the excitation of surface plasmons, a strong electromagnetic field is induced at the interfaces of a metallic nanoparticle leading to a drastic enhancement of the Raman scattering cross‐section. Furthermore, the Raman scattered light expierences an emission enhancement due to the plasmon resonances of the nanoantennas. Herein, this second part of the electromagnetic enhancement phenomenon is investigated for different Raman bands of crystal violet by utilizing the anisotropic plasmonic character of gold nanorhomb SERS arrays. We aim at evaluating the effects of localized and propagating surface plasmon polariton modes as well as their combination on the scattered SERS intensity. From that point of view, design and fabrication strategies towards the fabrication of SERS arrays for excitation wavelengths in the visible and near‐infrared (NIR) spectral region can be given, also using a double‐resonant electromagnetic enhancement.
Monolithisches Mauerwerk aus Leichtbetonsteinen erfüllt die Anforderungen der Energieeinsparverordnung 2009
Authors: Schrenk Johannes , Maier Martin
Published: April 2010

Die Energieeinsparverordnung (EnEV) 2009 beinhaltet verschärfte Anforderungen an den Jahresprimärenergiebedarf und den Transmissionswärmeverlust von Gebäuden. Damit sinkt der durchschnittliche U‐Wert von Außenwänden auf 0,28 W/(m2K). Mauersteine aus haufwerksporigem Leichtbeton wurden in den letzten Jahren wärmetechnisch so verbessert, dass sich diese Anforderungen mit Mauerwerksdicken von 36,5 cm problemlos erfüllen lassen. Selbst die Kriterien für ein KfW‐Effizienzhaus 70 oder 55 lassen sich auf diese Weise mit monolithischem Mauerwerk ohne zusätzliche Dämmung noch einhalten.

Monolithic masonry made of lightweight concrete blocks meets demands of energy saving regulations. The Decree for Saving Energy (Energieeinsparverordnung, EnEV — regulation for energy saving in buildings and building systems) 2009 consists stronger regulations for the yearly demand of energy and the loss of transmission heat of buildings. Therefore the average U‐Value for enclosure walls decreases to 0.28 W/(m2K). Blocks made of aggregate lightweight concrete have been improved by the industry concerning their thermal conductivity in the last years, so these demands can be fulfilled with masonry in 36,5 cm thickness. Even the criteria of a KfW Efficiency House 70 or 55 can be fulfilled in this way with monolithic masonry without an additional thermal insulation.
Mauerwerksbauten des Wohnungsbaus unter Erdbebeneinwirkung
Authors: Jäger Wolfram , Nguyen Song Ha , Schöps Peter
Published: April 2010

Es werden die Ergebnisse eines Forschungsvorhabens vorgestellt, das vom Bundesamt für Bauwesen und Raumordnung gefördert worden ist und an ein vorheriges zu Mauerwerksbauten in Erdbebenzone 1 anschließt [1]. Mit Hilfe eines angepassten Materialgesetzes sind für standardmäßige Mauerwerksbauten des Wohnungsbaus die erforderlichen Schubwandquerschnitte gemäß DIN 4149 nachgerechnet worden. Die dort enthaltene Tabelle hat den Vorteil, dass auf einen Nachweis verzichtet werden kann, wenn die angegebenen Mindestquerschnittsflächen eingehalten sind. Diese konnten i.W. bestätigt bzw. in vielen Fällen sogar noch verringert werden, wenn man für die jeweiligen Stein‐Mörtel‐Kombinationen die entsprechenden Materialkennwerte ansetzt.

Masonry structures in housebuilding under earthquake actions. Definition of structural provisions for abdication of calculational verification in the earthquake zones 2 and 3. Results of a research project funded by the Federal Office for Building and Regional Planning will be presented. It affiliates to a previous one on masonry structures in earthquake zone 1 [1]. The necessary crosssection areas according to DIN 4149 were recalculated for standard masonry structures for housebuilding. The there contained table has the advantage, that a calculational verification should not be done if the cross sectional area of the stiffening walls comply with the given minimum values. These values could be approved in generally and accordingly reduced in most cases, if the adequate material data were used for the respectively unitmortar‐combination.
Malignant solitary fibrous tumors in a renal allograft: The nephron‐sparing surgery option
Authors: Casaccia Marco , Fontana Iris , Nardi Ilaria , Bertocchi Massimo , Ghinolfi Davide , Sturdevant Mark , Gentile Raffaella , Valente Umberto
Published: April 2010

Malignant solitary fibrous tumors (SFT) of the kidney are an unusual entity. In a search of the medical literature, this tumor has never been described in a renal allograft. We report a case of a 70‐year‐old female who developed a bifocal malignant SFT in a renal allograft 12 years after transplantation. The patient underwent enucleation of both lesions. Microscopic evaluation showed neoplastic proliferation of spindle‐shaped cells showing moderate atypia and frequent mitotic figures.

At 12‐month follow‐up, the patient was tumor‐free and had preserved renal allograft function. Although transplant nephrectomy might be the conventional treatment for this pathology, a nephron‐sparing surgical approach allowed for the removal of both tumors while preserving allograft function. In this case, an informed patient dictated a treatment modality that would best maintain her high quality of life coupled with a reasonable expectation of a cure.
The dilemma of undocumented immigrants with ESRD
Authors: Rodriguez Rudolph A.
Published: April 2010

The National Kidney Foundation (NKF) 2010 Spring Clinical Meetings will take place April 13‐17 at the Walt Disney World Swan and Dolphin Hotel in Orlando, Fla. These multi‐disciplinary meetings will present opportunities for renal healthcare providers to learn new developments related to all aspects of nephrology, and are designed for nephrologists in the private sector and academia, fellows and residents with a special interest in kidney disease, general internists, pharmacists, physician assistants, nurse practitioners, nurses and technicians, social workers, and renal and clinical dietitians. In a session entitled “Special Issues in Minority Populations,” the NKF will provide a forum for discussion of “Dialysis of Undocumented Immigrants,” among other topics. The following article presents the viewpoint of Rudy A. Rodriguez, MD, who will be speaking at that session. Dial.
A Photo‐Caged Platinum(II) Complex That Increases Cytotoxicity upon Light Activation
Authors: Ciesienski Katie L. , Hyman Lynne M. , Yang Daniel T. , Haas Kathryn L. , Dickens Marina G. , Holbrook Robert J. , Franz Katherine J.
Published: April 2010

A novel platinum(II) photocaged complex called [Pt(cage)] has been prepared and characterized by X‐ray crystallography. The complex contains a photolabile nitrophenyl group incorporated into the backbone of a tetradentate ligand that contains two pyridyl and two amide nitrogen donor sites. The intact complex is unreactive toward ligand‐exchange reactions until activation with UV light cleaves the ligand backbone, releasing a PtII complex that more readily exchanges its ligands, as verified by reaction with a methionine‐containing peptide. [Pt(cage)] is non‐toxic to MCF‐7 cells in the dark, whereas brief UV exposure induces cell death of human breast cancer MCF‐7 cells at a level approaching that of cisplatin. By using light to alter the coordination chemistry around the metal center, [Pt(cage)] represents a new strategy for potentially delivering metal‐based drugs in a site and time specific manner.
The mitochondrial proteome: A dynamic functional program in tissues and disease states
Authors: Balaban Robert S.
Published: April 2010

The nuclear DNA transcriptional programming of the mitochondria proteome varies dramatically between tissues depending on its functional requirements. This programming generally regulates all of the proteins associated with a metabolic or biosynthetic pathway associated with a given function, essentially regulating the maximum rate of the pathway while keeping the enzymes at the same molar ratio. This may permit the same regulatory mechanisms to function at low‐ and high‐flux capacity situations. This alteration in total protein content results in rather dramatic changes in the mitochondria proteome between tissues. A tissues mitochondria proteome also changes with disease state, in Type 1 diabetes the liver mitochondrial proteome shifts to support ATP production, urea synthesis, and fatty acid oxidation. Acute flux regulation is modulated by numerous posttranslational events that also are highly variable between tissues. The most studied posttranslational modification is protein phosphorylation, which is found all of the complexes of oxidative phosphorylation and most of the major metabolic pathways. The functional significance of these modifications is currently a major area of research along with the kinase and phosphatase regulatory network. This near ubiquitous presence of protein phosphorylations, and other posttranslational events, in the matrix suggest that not all posttranslational events have functional significance. Screening methods are being introduced to detect the active or dynamic posttranslational sites to focus attention on sites that might provide insight into regulatory mechanisms. Environ. Mol. Mutagen., 2010. Published 2010 Wiley‐Liss, Inc.
Determining the molecular interactions of perfluorinated carboxylic acids with human sera and isolated human serum albumin using nuclear magnetic resonance spectroscopy
Authors: D'eon Jessica C. , Simpson André J. , Kumar Rajeev , Baer Andrew J. , Mabury Scott A.
Published: April 2010

Perfluorooctanoate (PFOA) is ubiquitous in North American human sera and has a serum half-life of 3.5 years in humans. The molecular interactions that lead to the bioaccumulation of these hydrophobic and lipophobic molecules in human blood are not well understood. Perfluorohexanoic acid (PFHxA) and PFOA were used as model perfluorinated carboxylic acids (PFCAs) to characterize the major site of PFCA interaction in human sera. Using novel heteronuclear saturation transfer difference nuclear magnetic resonance spectroscopy experiments, human serum albumin (HSA) was identified as the major site of interaction for both PFHxA and PFOA in human sera. Heteronuclear single quantum coherence nuclear magnetic resonance experiments were then performed to interrogate site-specific interactions of PFHxA and PFOA with isolated HSA. Perfluorohexanoic acid was found to bind specifically to Sudlow's drug-binding site II, whereas PFOA interacted preferentially with Sudlow's drug-binding site I at the lower concentration, with additional interactions developing at the higher concentration. These experiments highlight the utility of nuclear magnetic resonance spectrometry as a tool to observe the in situ interactions of chemical contaminants with biological systems. Both PFCAs displaced the endogenous HSA ligand oleic acid at concentrations lower than observed for the drugs ibuprofen and phenylbutazone, which are established HSA ligands. Interactions between PFCAs and HSA may affect the pharmacokinetics and distribution of fatty acids and certain drugs in the human body and warrant further investigation. Environ. Toxicol. Chem. 2010; 29:1678–1688. © 2010 SETAC
Early parietal response in episodic retrieval revealed with MEG
Authors: Seibert Tyler M. , Hagler Donald J. , Brewer James B.
Published: April 2010

Recent neuroimaging and lesion studies have led to competing hypotheses for potential roles of the left lateral parietal lobe in episodic memory retrieval. These hypotheses may be dissociated by whether they imply a role in preretrieval or postretrieval processes. For example, one hypothesis is the left parietal cortex (particularly in more ventral subregions) forms part of an “episodic buffer” that supports the online representation of the retrieved target, a role that is, by definition, postretrieval. An alternate view maintains parietal activity (particularly in more dorsal subregions) contributes to top‐down orientation of attention to retrieval search, a preretrieval role. The present investigation seeks to reveal the earliest onset of lateral parietal activity in three anatomically‐defined subregions of the left lateral parietal cortex to identify any preretrieval activation. Subjects performed a pair‐cued recall task while neural activity was recorded with magnetoencephalography (MEG) at millisecond temporal resolution. MEG data were then mapped to each subject's cortical surface using dynamic statistical parametric mapping (dSPM). Both dorsal and ventral regions showed retrieval‐related activations beginning within ∼100 ms of the cue to retrieve and lasting up to 400 ms. We conclude that this early and transient pattern of activity in lateral parietal cortex is most consistent with a preretrieval role, possibly in directing attention to episodic memory retrieval. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
β‐Band correlates of the fMRI BOLD response
Authors: Stevenson Claire M. , Brookes Matthew J. , Morris Peter G.
Published: April 2010

Oscillatory activity in the β‐band (15–30 Hz) has been studied in detail in the sensorimotor cortex. It has been postulated that β‐activity acts as a localized gating of cortical activity. Here, the induced oscillatory response in the β‐band is measured by magnetoencephalography, and the hemodynamic response is measured by fMRI. We assess the linearity of the responses to stimuli of varying duration in the primary motor cortex and to a sinusoidal drifting grating of varying contrast amplitude and drift frequency in the visual cortex. In this way, we explore the nature of β‐oscillations and their relationship with hemodynamic effects. Excellent spatial colocalization of BOLD and β‐activity in both central and lateral (MT) visual areas and sensorimotor areas suggests that the two are intimately related. In contrast to the BOLD response, the level of β‐desynchronization is not modulated by stimulus contrast or by stimulus duration, consistent with a gating role. The amplitude of β‐desynchronization in the central visual area is however modulated by drift frequency, and this seems to parallel the modulation in BOLD amplitude at the same location. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Reward and motivation systems: A brain mapping study of early‐stage intense romantic love in Chinese participants
Authors: Xu Xiaomeng , Aron Arthur , Brown Lucy , Cao Guikang , Feng Tingyong , Weng Xuchu
Published: April 2010

Early‐stage romantic love has been studied previously in the United States and United Kingdom (Aron et al. [2005]: J Neurophysiol 94:327–337; Bartels and Zeki [2000]: Neuroreport 11:3829–3834; Ortigue et al. [2007]: J Cogn Neurosci 19:1218–1230), revealing activation in the reward and motivation systems of the brain. In this study, we asked what systems are activated for early‐stage romantic love in Easterners, specifically Chinese participants? Are these activations affected by individual differences within a cultural context of Traditionality and Modernity? Also, are these brain activations correlated with later satisfaction in the relationship? In Beijing, we used the same procedure used by Aron et al. (Aron et al. [2005]: J Neurophysiol 94:327–337). The stimuli for 18 Chinese participants were a picture of the face of their beloved, the face of a familiar acquaintance, and a countback task. We found significant activations specific to the beloved in the reward and motivation systems, particularly, the ventral tegmental area and the caudate. The mid‐orbitofrontal cortex and cerebellum were also activated, whereas amygdala, medial orbitofrontal, and medial accumbens activity were decreased relative to the familiar acquaintance. Self‐reported Traditionality and Modernity scores were each positively correlated with activity in the nucleus accumbens, although in different regions and sides of the brain. Activity in the subgenual area and the superior frontal gyrus was associated with higher relationship happiness at 18‐month follow‐up. Our results show that midbrain dopamine‐rich reward/motivation systems were activated by early‐stage romantic love in Chinese participants, as found by other studies. Neural activity was associated with Traditionality and Modernity attitudes as well as with later relationship happiness for Chinese participants. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Implicit sequence‐specific motor learning after subcortical stroke is associated with increased prefrontal brain activations: An fMRI Study
Authors: Meehan Sean K. , Randhawa Bubblepreet , Wessel Brenda , Boyd Lara A.
Published: April 2010

Implicit motor learning is preserved after stroke, but how the brain compensates for damage to facilitate learning is unclear. We used a random effects analysis to determine how stroke alters patterns of brain activity during implicit sequence‐specific motor learning as compared to general improvements in motor control. Nine healthy participants and nine individuals with chronic, right focal subcortical stroke performed a continuous joystick‐based tracking task during an initial functional magnetic resonance images (fMRI) session, over 5 days of practice, and a retention test during a separate fMRI session. Sequence‐specific implicit motor learning was differentiated from general improvements in motor control by comparing tracking performance on a novel, repeated tracking sequence during early practice and again at the retention test. Both groups demonstrated implicit sequence‐specific motor learning at the retention test, yet substantial differences were apparent. At retention, healthy control participants demonstrated increased blood oxygenation level dependent (BOLD) response in left dorsal premotor cortex (PMd; BA 6) but decreased BOLD response left dorsolateral prefrontal cortex (DLPFC; BA 9) during repeated sequence tracking. In contrast, at retention individuals with stroke did not show this reduction in DLPFC during repeated tracking. Instead implicit sequence‐specific motor learning and general improvements in motor control were associated with increased BOLD response in the left middle frontal gyrus BA 8, regardless of sequence type after stroke. These data emphasize the potential importance of a prefrontal‐based attentional network for implicit motor learning after stroke. This study is the first to highlight the importance of the prefrontal cortex for implicit sequence‐specific motor learning after stroke. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Double dissociation between syntactic gender and picture naming processing: A brain stimulation mapping study
Authors: Vidorreta Jose Garbizu , Garcia Roser , Moritz‐Gasser Sylvie , Duffau Hugues
Published: April 2010

Neural foundations of syntactic gender processing remain poorly understood. We used electrostimulation mapping in nine right‐handed awake patients during surgery for a glioma within the left hemisphere, to study whether the cortico‐subcortical structures involved in naming versus syntactic gender processing are common or distinct. In French, the article determines the grammatical gender. Thus, the patient was asked to perform a picture naming task and to give the appropriate article for each picture, with and without stimulation. Cortical stimulation elicited reproducible syntactic gender disturbances in six patients, in the inferior frontal gyrus (three cases), and in the posterior middle temporal gyrus (three cases). Interestingly, no naming disorders were generated during stimulation of the syntactic sites, while cortical areas inducing naming disturbances never elicited grammatical gender errors when stimulated. Moreover, at the subcortical level, stimulation of the white matter lateral to the caudate nucleus induced gender errors in three patients, with no naming disorders. Using cortico‐subcortical electrical mapping in awake patients, we demonstrate for the first time (1) a double dissociation between syntactic gender and naming processing, supporting independent network model rather than serial theory, (2) the involvement of the left inferior frontal gyrus, especially the pars triangularis, and the posterior left middle temporal gyrus in grammatical gender processing, (3) the existence of white matter pathways, likely a sub‐part of the left superior longitudinal fasciculus, underlying a large‐scale distributed cortico‐subcortical circuit which might selectively sub‐serve syntactic gender processing, even if interconnected with parallel sub‐networks involved in naming (semantic and phonological) processing. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
An executive's guide to SOX audits
Authors: Paul Jack W.
Published: April 2010

Auditors aren't the only ones who need a sharp understanding of internal control audits. Savvy CEOs and other executives also need this knowledge—to save time, money, and even professional careers. Because, as most readers know, CEOs and CFOs must now certify the veracity of their company's financial statements—under threat of heavy criminal penalties.

So, how thorough is your knowledge about internal control audits? Let the author of this article lead you step by step through the process, as he offers advice on avoiding pitfalls and points out possible warning signs. © 2010 Wiley Periodicals, Inc.
IRS victory jeopardizes workpaper confidentiality
Authors: Sonnier Blaise M.
Published: April 2010

A decision by the First Circuit Court of Appeals was a dismaying surprise to many observers. It sets a new stringent standard to claim confidentiality for tax accrual and other workpapers. What is the impact of this startling decision? What can companies do now to retain privacy for workpapers? The author examines the issues and offers some practical advice. © 2010 Wiley Periodicals, Inc.
Auditing your cash conversion
Authors: Reider Rob
Published: April 2010

You are in the cash conversion business—to create desired goods and services, so that the investment in the business is converted to cash as quickly as possible. The author explains how to audit your cash conversion processes to increase net profits. © 2010 Wiley Periodicals, Inc.
Branch migration of Holliday junction in RuvA tetramer complex studied by umbrella sampling simulation using a path‐search algorithm
Authors: Ishida Hisashi
Published: April 2010

Branch migration of the Holliday junction takes place at the center of the RuvA tetramer. To elucidate how branch migration occurs, umbrella sampling simulations were performed for complexes of the RuvA tetramer and Holliday junction DNA. Although conventional umbrella sampling simulations set sampling points a priori, the umbrella sampling simulation in this study set the sampling points one by one in order to search for a realistic path of the branch migration during the simulations. Starting from the X‐ray structure of the complex, in which the hydrogen bonds between two base‐pairs were unformed, the hydrogen bonds between the next base‐pairs of the shrinking stems were observed to start to disconnect. At the intermediate stage, three or four of the eight unpaired bases interacted closely with the acidic pins from RuvA. During the final stage, these bases moved away from the pins and formed the hydrogen bonds of the new base‐pairs of the growing stems. The free‐energy profile along this reaction path showed that the intermediate stage was a meta‐stable state between two free‐energy barriers of about 10 to 15 kcal/mol. These results imply that the pins play an important role in stabilizing the interactions between the pins and the unpaired base‐pairs. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Parallel Fock matrix construction with distributed shared memory model for the FMO‐MO method
Authors: Umeda Hiroaki , Inadomi Yuichi , Watanabe Toshio , Yagi Toru , Ishimoto Takayoshi , Ikegami Tsutomu , Tadano Hiroto , Sakurai Tetsuya , Nagashima Umpei
Published: April 2010

A parallel Fock matrix construction program for FMO‐MO method has been developed with the distributed shared memory model. To construct a large‐sized Fock matrix during FMO‐MO calculations, a distributed parallel algorithm was designed to make full use of local memory to reduce communication, and was implemented on the Global Array toolkit. A benchmark calculation for a small system indicates that the parallelization efficiency of the matrix construction portion is as high as 93% at 1,024 processors. A large FMO‐MO application on the epidermal growth factor receptor (EGFR) protein (17,246 atoms and 96,234 basis functions) was also carried out at the HF/6‐31G level of theory, with the frontier orbitals being extracted by a Sakurai‐Sugiura eigensolver. It takes 11.3 h for the FMO calculation, 49.1 h for the Fock matrix construction, and 10 min to extract 94 eigen‐components on a PC cluster system using 256 processors. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Solving the low dimensional Smoluchowski equation with a singular value basis set
Authors: Scott Gregory , Gruebele Martin
Published: April 2010

Reaction kinetics on free energy surfaces with small activation barriers can be computed directly with the Smoluchowski equation. The procedure is computationally expensive even in a few dimensions. We present a propagation method that considerably reduces computational time for a particular class of problems: when the free energy surface suddenly switches by a small amount, and the probability distribution relaxes to a new equilibrium value. This case describes relaxation experiments. To achieve efficient solution, we expand the density matrix in a basis set obtained by singular value decomposition of equilibrium density matrices. Grid size during propagation is reduced from (100–1000)N to (2–4)N in N dimensions. Although the scaling with N is not improved, the smaller basis set nonetheless yields a significant speed up for low‐dimensional calculations. To demonstrate the practicality of our method, we couple Smoluchowsi dynamics with a genetic algorithm to search for free energy surfaces compatible with the multiprobe thermodynamics and temperature jump experiment reported for the protein α3D. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Vectorial TGFβ signaling in polarized intestinal epithelial cells
Authors: Yakovich Adam J. , Huang Qin , Du Jianguo , Jiang Bo , Barnard John A.
Published: April 2010

Polarized gastrointestinal epithelial cells form tight junctions that spatially separate apical and basolateral cell membrane domains. These domains harbor functionally distinct proteins that contribute to cellular homeostasis and morphogenesis. Transforming growth factor β (TGFβ) is a critical regulator of gastrointestinal epithelial cell growth and differentiation. Functional assays of vectorial TGFβ signaling and immunofluorescence techniques were used to determine the localization of TGFβ receptors and ligand secretion in polarizing Caco‐2 cells, a colon cancer cell line. Results were compared to the nontransformed MDCK cell line. In both Caco‐2 and MDCK cells, addition of TGFβ1 to the basolateral medium resulted in phosphorylation of Smad2. No phosphorylation was observed when TGFβ1 was added to the apical chamber, indicating that receptor signaling is localized at the basolateral membrane. In support of this, immunofluorescence and biotinylation assays show receptor localization along the basolateral membrane. Secretion of TGFβ1 from MDCK and Caco‐2 cells into the apical or basolateral medium was measured by ELISA. Interestingly, secretion was exclusively apical in the nontransformed MDCK line and basolateral in transformed Caco‐2 cells. Collectively, these results show basolateral domain specificity in localization of the TGFβ receptor signaling apparatus. These observations have important implications for understanding the biology of TGFβ in polarized epithelia, including elements of communication between epithelial and mesenchymal layers, and will prove useful in the design of therapeutics that target TGFβ function. J. Cell. Physiol. 224: 398–404, 2010. © 2010 Wiley‐Liss, Inc.
Enhanced islet expansion by β‐cell proliferation in young diabetes‐prone rats fed a protective diet
Authors: Wang Gen‐Sheng , Kauri Lisa M. , Patrick Christopher , Bareggi Mirella , Rosenberg Lawrence , Scott Fraser W.
Published: April 2010

Type 1 diabetes is inhibited in diabetes‐prone BioBreeding (BBdp) rats fed a low‐antigen hydrolyzed casein (HC) diet. In cereal‐fed BBdp rats, islet expansion is defective accompanied by a futile upregulation of islet neogenesis without increased islet mass, due to a subtle blockage in islet cell cycle. We hypothesized that islet growth is enhanced before insulitis in HC‐fed young BBdp rats and that islet neogenesis could be stimulated by a trophic factor, islet neogenesis‐associated protein (INGAP). β‐Cell homeostasis was analyzed using immunohistochemistry, morphometry, laser capture microdissection and RT‐PCR in BBdp rats fed HC or cereal diets. β‐cell proliferation in small and medium islets, and the number and area fraction of medium and large islets were increased in HC‐fed animals. In situ islet cell cycle analysis revealed an increased proportion of proliferating S + G2 cells in medium and large islets of 25–45 day HC‐fed rats. Expression of the cell cycle inhibitor, p16INK4a correlated with islet size and the percentage of p16INK4a+ β‐cells increased in HC‐fed BBdp rats, likely reflecting an increase in large islet area fraction. In HC‐fed rats, extra‐islet insulin+ clusters (EIC), insulin+ duct cells, large islet area fraction, and β‐cell mass were increased. Neurogenin‐3 and Pdx‐1, markers of β‐cell progenitors, were increased in EIC of weanling HC‐fed rats. Daily injection of INGAP (30–45 days) increased the number of small islets, total islets, and insulin+ cells in small ducts. Thus, in BBdp rats fed a protective HC diet, β‐cell expansion is enhanced through increased β‐cell proliferation and stimulation of islet neogenesis. J. Cell. Physiol. 224: 501–508, 2010. © 2010 Wiley‐Liss, Inc.
Expression profiling of ETS and MMP factors in VEGF‐activated endothelial cells: Role of MMP‐10 in VEGF‐induced angiogenesis
Authors: Heo Sun‐Hee , Choi Young‐Jin , Ryoo Hyun‐Mo , Cho Je‐Yoel
Published: April 2010

In the process of angiogenesis, working of many transcription factors at the proper time is important to activate angiogenesis‐related genes such as cytokine, matrix protease and adhesion molecules. In this study, we searched for Ets transcription factors and matrix metalloproteinases (MMPs) that respond to VEGF in endothelial cells. We first analyzed the expression of 27 human Ets factors and 15 human MMPs in VEGF‐treated human umbilical vein endothelial cells (HUVEC) using quantitative RT‐PCR. The most abundant Ets factors in HUVEC were ETS‐1, Fli‐1, ERP/NET/ELK3, and ERG. MMP‐1, ‐2, ‐10, ‐11, ‐14, ‐15, and ‐16 were also detected in HUVEC. We also found that ETV‐1, Fli‐1, ERG, MMP‐1, ‐3, ‐7, ‐8, ‐9, ‐10, ‐13, and ‐19 expression is up‐regulated more than 1.5‐fold in HUVEC after 2 h of VEGF treatment. In addition, the expression of MMP‐10 induced by VEGF remained twofold higher for 24 h compared to non‐treated control. The elevation of MMP10 mRNA and protein levels was confirmed to be both time‐ and dosage‐dependent. In addition, MMP‐10 transcription was mediated by Ets‐1 but not ERP/NET/ELK3. The inhibition of PI3K and MAPK inhibited VEGF‐induced MMP‐10 expression. Furthermore, transfection of MMP‐10 siRNA inhibited VEGF‐induced migration and tube formation in HUVEC, and it also inhibited vessel formation in matrigel plugs in vivo. In conclusion, our study demonstrated induction of MMP‐10 by VEGF in HUVEC and supports an angiogenic role for MMP‐10 in response to VEGF stimulation in vitro and in vivo. J. Cell. Physiol. 224: 734–742, 2010. © 2010 Wiley‐Liss, Inc.
Postembryonic development of Antygomonas incomitata (Kinorhyncha: Cyclorhagida)
Authors: Sørensen Martin V. , Accogli Gianluca , Hansen Jesper G.
Published: April 2010

Postembryonic development in the kinorhynch species Antygomonas incomitata was examined using scanning electron microscopy. The morphology of the six juvenile stages, J‐1 to J‐6, varies at numerous details, but they can also be distinguished by a few key characters. Juvenile stage 1 by its composition of only nine trunk segments; J‐2 by the combination of possessing 10 trunk segments, but no cuspidate spines on segment 9; J‐3 by the presence of cuspidate spines on segment 9, but only one pair of cuspidate spines on segment 8; J‐4 by the combination of 10 trunk segments only, but having two pairs of cuspidate spines on segment 8; J‐5 by possessing 11 trunk segments and same spine compositions as adults but is still maintaining postmarginal spiculae; J‐6 specimens closely resemble adults and are most easily identified by their reduced trunk lengths. New segments are formed in a growth zone in the anterior part of the terminal segment. The complete number of segments is reached in J‐5. Development of cuticular head and trunk structures are described through all postembryonic stages and following developmental patterns could be outlined: the mouth cone possesses outer oral styles from J‐1, but in J‐1 to J‐3, the styles alternate in size. Scalids of the introvert are added after each molt, and scalids appear earliest in the anterior rings, whereas scalids in more posterior rings are added in older postembryonic stages. The early J‐1 stage is poor in spines and sensory spots and both structures increase in number after each molt. The complete spine composition is reached in J‐4, whereas new sensory spots appear after all molts, inclusive the final one from J‐6 to adult. Sensory spots in the paraventral positions often appear as Type 3 sensory spots but are through development transformed to Type 2. This transformation happens earliest on the anterior segments. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.
Molecular Recognition Induced Self‐Assembly of Diblock Copolymers: Microspheres to Vesicles
Authors: Uzun Oktay , Sanyal Amitav , Jeong Youngdo , Rotello Vincent M.
Published: April 2010

Random diblock copolymer scaffolds grafted with diamidopyridine (DAP) hydrogen bonding recognition units self‐assembled to furnish microspheres when mixed with monoblock copolymers decorated with complementary recognition elements. Through choice of block length, microspheres of various sizes could be produced. The relative length of the two blocks plays a crucial role in determining the formation of aggregates. PEG‐b‐P(S‐co‐SDAP) diblock copolymer was used to fabricate recognition induced pegylated microspheres, by non‐covalent crosslinking with monoblock copolymer functionalized with complementary thymine (Thy) units. These self‐assembled microspheres can be efficiently crosslinked via photochemical [2πs + 2πs] cycloaddition with the resultant morphology change into vesicular structures.

magnified image