bluuebunny/crossref_metadata_2025_split huggingface dataset:
Messung der Nachhallzeiten in großen und/oder leeren Räumen
Authors: Eßer Georg , Schäfer Thomas 
Published: April 2012

AbstractDer Anspruch an die akustische Qualität eines Raumes nimmt immer mehr an Bedeutung zu. Dadurch nimmt auch die Zahl der Messungen der Nachhallzeiten in Räumen, für die Anforderungen nach DIN 18041 [1] gestellt oder Maßnahmen empfohlen werden, zu. Oft sind schon vor der Möblierung die Nachhallzeiten messtechnisch zu prüfen und mit den Anforderungen zu vergleichen oder aus Nachhallzeitmessungen zu ermitteln, ob der Empfehlung an die mit Schallabsorbern zu bekleidende Raumbegrenzungsfläche entsprochen wird. Je nach Anordnung der Schallabsorber werden diese im leeren Raum nicht ausreichend “angeregt“, um entsprechend schallabsorbierend zu wirken. Insbesondere in großen Räumen, wie z. B. Sporthallen, in denen oft die schallabsorbierenden Maßnahmen an den Decken angebracht werden, tritt dieser “Effekt“ auf. Zusätzlich für die Nachhallzeitmessungen in den leeren Raum eingebrachte Streukörper führen zu einer Verringerung der Nachhallzeit und sind geeignet, den Nutzungszustand besser abzubilden. Bei Räumen, bei denen Empfehlungen an die mit Schallabsorbern zu bekleidende Raumbegrenzungsfläche gestellt werden, erfordert die messtechnische Überprüfung mit Hilfe von Nachhallzeitmessungen diffuse Schallfeldbedingungen. Anhand von Messbeispielen in Sporthallen und Büroräumen werden die Auswirkungen von Streukörpern aufgezeigt.Measuring reverberation times in large and/or empty rooms. The demands for good room acoustics are increasing all the time. This also means that more reverberation time measurements have to be carried out in rooms that are subject to DIN 18041 requirements. Often, these measurements have to be carried out before the furniture arrives, e.g. in offices and classrooms, and the results have to be compared with the requirements. Depending on the arrangement and layout of sound absorption devices it is possible that these are not sufficiently “excited” in empty rooms and therefore fail to have the intended effect. This effect occurs particularly in large rooms, such as sports halls, in which the sound absorption devices are fitted to the ceilings. In these situations it is necessary to use diffusers. The effect of diffusers is illustrated using examples of measurements in sports halls and offices.
Animating strings with twisting, tearing and flicking effects
Authors: Rungjiratananon Witawat , Kanamori Yoshihiro , Metaaphanon Napaporn , Bando Yosuke , Chen Bing‐Yu , Nishita Tomoyuki 
Published: April 2012

ABSTRACTString‐like objects in our daily lives, for example shoelaces, threads, rubber cords, plastic fiber and spaghetti, have a wide variety of materials. Such string‐like objects also exhibit interesting behaviors such as twisting, tearing (by stretching or twisting), and bouncing back when pulled and released. In this paper, we present a method that enables these behaviors and simulates such materials in traditional string simulation methods that explicitly represent a string by particles and segments. Specifically, we offer the following three contributions. First, we introduce a method for handling twisting effects with both uniform and non‐uniform torsional rigidities. Second, we propose a method for estimating the tension acting on inextensible strings in order to reproduce tearing and flicking (bouncing back), whereas the tension for an extensible object can be computed via stretched length. The length of an inextensible object is maintained constant in general, and thus, we need a novel approach. Third, we introduce an optimized grid‐based collision detection for accelerating the computation. We demonstrate that our method can produce visually plausible animations of string‐like objects with various material properties, and it is a fast framework for interactive applications such as games. Copyright © 2012 John Wiley & Sons, Ltd.
Mesoporous Silica Nanoparticle‐Stabilized and Manganese‐Modified Rhodium Nanoparticles as Catalysts for Highly Selective Synthesis of Ethanol and Acetaldehyde from Syngas
Authors: Huang Yulin , Deng Weihua , Guo Enruo , Chung Po‐Wen , Chen Senniang , Trewyn Brian G. , Brown Robert C. , Lin Victor S.‐Y. 
Published: April 2012

AbstractWell‐defined and monodispersed rhodium nanoparticles as small as approximately 2 nm were encapsulated in situ and stabilized in a mesoporous silica nanoparticle (MSN) framework during the synthesis of the mesoporous material. Although both the activity and selectivity of MSN‐encapsulated rhodium nanoparticles in CO hydrogenation could be improved by the addition of manganese oxide as expected, the carbon selectivity for C2 oxygenates (including ethanol and acetaldehyde) was unprecedentedly high at 74.5 % with a very small amount of methanol produced if rhodium nanoparticles were modified by manganese oxide with very close interaction.
The Kinetic Features of the Palladium‐Catalyzed Hydrogenolysis of Nitriles and Amines
Authors: Yap Aaron J. , Masters Anthony F. , Maschmeyer Thomas 
Published: April 2012

AbstractA model of the kinetics underlying the hydrogenolysis of nitriles and amines, catalysed by Pd/C, has been derived. Benzonitrile and benzylamine were used as archetypical compounds to better understand the various reaction pathways involved in these processes. The reaction order under mild conditions (80 °C, 1 bar H2) for the hydrogenolysis of benzylamine was zero order in benzylamine, indicating strong adsorption of benzylamine to the catalyst, whereas the hydrogenation of benzonitrile was found to be first order in benzonitrile, owing to mass transport limitations, explaining the observed selectivities toward hydrogenolysis versus hydrogenation. Significantly, benzylamine itself was found to reversibly poison the hydrogenolysis function of the catalyst, preventing high yields of hydrogenolysis products at low catalyst loadings.
Palladium‐Based Catalytic System for the Direct C3‐Arylation of Furan‐2‐carboxamides and Thiophene‐2‐carboxamides
Authors: Si Larbi Karima , Fu Hai Yan , Laidaoui Nouria , Beydoun Kassem , Miloudi Abdellah , El Abed Douniazad , Djabbar Safia , Doucet Henri 
Published: April 2012

AbstractThe palladium‐catalyzed direct arylation of furans or thiophenes that contained secondary carboxamides at the C2 position proceeded regioselectively at either the C3 or C5 positions, depending on the reaction conditions. The nature of the base was crucial for controlling the regioselectivity of the reaction. We had previously observed that, in the presence of potassium acetate, direct arylation at the C5 position was favored. Herein, we report that the use of cesium carbonate as the base and xylene as the solvent selectively afforded the C3‐arylated furans or thiophenes. The reactivity of furan‐2‐carboxamides and thiophene‐2‐carboxamides were similar. The reaction tolerated a range of functional groups on the aryl bromide and also heteroaryl bromide substrates.
An Optimised Small‐Molecule Stabiliser of the 14‐3‐3–PMA2 Protein–Protein Interaction
Authors: Richter Anja , Rose Rolf , Hedberg Christian , Waldmann Herbert , Ottmann Christian 
Published: April 2012

AbstractModulation of protein–protein interactions (PPIs) is a highly demanding, but also a very promising approach in chemical biology and targeted drug discovery. In contrast to inhibiting PPIs with small, chemically tractable molecules, stabilisation of these interactions can only be achieved with complex natural products, like rapamycin, FK506, taxol, forskolin, brefeldin and fusicoccin. Fusicoccin stabilises the activatory complex of the plant H+‐ATPase PMA2 and 14‐3‐3 proteins. Recently, we have shown that the stabilising effect of fusicoccin could be mimicked by a trisubstituted pyrrolinone (pyrrolidone1, 1). Here, we report the synthesis, functional activity and crystal structure of derivatives of 1 that stabilise the 14‐3‐3–PMA2 complex. With a limited compound collection three modifications that are important for activity enhancement could be determined: 1) conversion of the pyrrolinone scaffold into a pyrazole, 2) introduction of a tetrazole moiety to the phenyl ring that contacts PMA2, and 3) addition of a bromine to the phenyl ring that exclusively contacts the 14‐3‐3 protein. The crystal structure of a pyrazole derivative of 1 in complex with 14‐3‐3 and PMA2 revealed that the more rigid core of this molecule positions the stabiliser deeper into the rim of the interface, enlarging especially the contact surface to PMA2. Combination of the aforementioned features gave rise to a molecule (37) that displays a threefold increase in stabilising the 14‐3‐3–PMA2 complex over 1. Compound 37 and the other active derivatives show no effect on two other important 14‐3‐3 protein–protein interactions, that is, with CRaf and p53. This is the first study that describes the successful optimisation of a PPI stabiliser identified by screening.
Endlagerung radioaktiver Abfälle
Authors: Röhlig Klaus‐Jürgen , Geckeis Horst , Mengel Kurt 
Published: April 2012

AbstractDieser erste einer Serie von drei Artikeln führt in den Themenkomplex “Entsorgung radioaktiver Abfälle” ein und benennt damit zusammenhängende gesellschaftliche und wissenschaftliche Fragestellungen. Es wird dargelegt, welche Arten und welche Mengen von radioaktiven Abfällen in Deutschland zu entsorgen sind. Die Autoren stellen die verschiedenen Entsorgungsoptionen dar, die in der Vergangenheit diskutiert wurden und sprechen sich für eine nachsorgefreie Endlagerung in tiefen geologischen Formationen aus. Sie erläutern Grundzüge der Endlagerkonzepte im Kristallingestein, in Tonen und Tonsteinen und im Steinsalz.
Laser‐capture microdissection and transcriptional profiling of the dorsomedial nucleus of the hypothalamus
Authors: Lee Syann , Bookout Angie L. , Lee Charlotte E. , Gautron Laurent , Harper Matthew J. , Elias Carol F. , Lowell Bradford B. , Elmquist Joel K. 
Published: April 2012

AbstractIdentifying neuronal molecular markers with restricted patterns of expression is a crucial step in dissecting the numerous pathways and functions of the brain. While the dorsomedial nucleus of the hypothalamus (DMH) has been implicated in a host of physiological processes, current functional studies have been limited by the lack of molecular markers specific for DMH. Identification of such markers would facilitate the development of mouse models with DMH‐specific genetic manipulations. Here we used a combination of laser‐capture microdissection (LCM) and gene expression profiling to identify genes that are highly expressed within the DMH relative to adjacent hypothalamic regions. Six of the most highly expressed of these genes, Gpr50, 4930511J11Rik, Pcsk5, Grp, Sulf1, and Rorβ, were further characterized by real‐time polymerase chain reaction (PCR) analysis and in situ hybridization histochemistry. The genes identified in this article will provide the basis for future gene‐targeted approaches for studying DMH function. J. Comp. Neurol. 520:3617–3632, 2012. © 2012 Wiley Periodicals, Inc.
Ionically Tagged Iron Complex‐Catalyzed Epoxidation of Olefins in Imidazolium‐Based Ionic Liquids
Authors: dos Santos Marcelo R. , Diniz Julia R. , Arouca Aline M. , Gomes Alexandre F. , Gozzo Fabio C. , Tamborim Silvia M. , Parize Alexandre L. , Suarez Paulo A. Z. , Neto Brenno A. D. 
Published: April 2012

AbstractA new ionophilic ligand and a new ionically tagged imidazolium‐based iron(III) complex were synthesized and applied in the air oxidation (also hydrogen peroxide) of alkenes in imidazolium‐based ionic liquids. At least ten recycling reactions were performed. The epoxidized olefin was obtained in very good yields of 84–91 %. Some important mechanistic insights are also provided based on electrospray ionization quadrupole–time of flight mass spectrometry for the oxidation reaction. These results indicate that oxidations can take place by two different pathways, depending on the reaction condition: a radical or a concerted mechanism. These results contribute towards a better understanding of iron‐catalyzed oxidation mechanisms.
Synthesis of triheptanoin and formulation as a solid diet for rodents
Authors: Semak Vladislav , Semakova Jana , Halbaut Lyda , Aso Ester , Ferrer Isidro , Calpena Ana , Escolano Carmen , Perales Jose Carlos 
Published: April 2012

AbstractTriheptanoin‐enriched diets have been successfully used in the experimental treatment of various metabolic disorders. Maximal therapeutic effect is achieved in the context of a ketogenic diet where triheptanoin oil provides 30–40% of the daily caloric intake. However, pre‐clinical studies using triheptanoin‐rich diets are hindered by the difficulty of administering to laboratory animals as a solid foodstuff. In the present study, we successfully synthesized triheptanoin to the highest standards of purity from glycerol and heptanoic acid, using sulfonated charcoal as a catalyst. Triheptanoin oil was then formulated as a solid, stable and palatable preparation using a ketogenic base and a combination of four commercially available formulation agents: hydrophilic fumed silica, hydrophobic fumed silica, microcrystalline cellulose, and talc. Diet compliance and safety was tested on C57Bl/6 mice over a 15‐week period, comparing overall status and body weight change.Practical applications: This work provides a complete description of (i) an efficient and cost‐effective synthesis of triheptanoin and (ii) its formulation as a solid, stable, and palatable ketogenic diet (triheptanoin‐rich; 39% of the caloric intake) for rodents. Triheptanoin‐rich diets will be helpful on pre‐clinical experiments testing the therapeutic efficacy of triheptanoin in different rodent models of human diseases. In addition, using the same solidification procedure, other oils could be incorporated into rodent ketogenic diet to study their dosage and long‐term effects on mammal health and development. This approach could be extremely valuable as ketogenic diet is widely used clinically for epilepsy treatment.
A Three‐Component Condensation for the Construction of the Spiro[indoline‐3,3′‐piperidin]‐2‐one Skeleton
Authors: Yang Hai‐Bin , Guan Xiao‐Yang , Wei Yin , Shi Min 
Published: April 2012

AbstractTreatment of pyridine and dimethyl acetylenedicarboxylate derivatives with N‐substituted isatylidene derivatives resulted in three‐component condensations, affording 1′,9a′‐dihydrospiro[indoline‐3,2‐quinolizin]‐2‐one derivatives in high yields and with good diastereoselectivities through 1,4‐dipolar cycloadditions.
Dual compensation strategy for real‐time hybrid testing
Authors: Chen Pei‐Ching , Tsai Keh‐Chyuan 
Published: April 2012

SUMMARYReal‐time hybrid testing is an experimental technique for evaluating the dynamic responses of structural systems under seismic loading. Servo‐hydraulic actuators, by nature, induce inevitable time delay between the command and the achieved displacements. This delay would lead to incorrect test results and even cause instability of the system; therefore, delay compensation is critical for stability and accuracy of hybrid simulations of structural dynamic response. In this paper, a dual delay compensation strategy is proposed by a combination of a phase lead compensator and a restoring force compensator. An outer‐loop feed‐forward phase lead compensator is derived by introducing the inverse model in the z domain. The adaptive law based on the gradient algorithm is used to estimate the system delay in the format of parametric model during the test. It is shown mathematically that the parameter in the delay estimator is guaranteed to converge. The restoring force compensator is adopted to improve the accuracy of experimental results especially when the structure is subjected to high frequency excitations. Finally, analytical simulations of an inelastic SDOF structure are conducted to investigate the feasibility of the proposed strategy. The accuracy of the dual compensation strategy is demonstrated through several shaking table tests. Copyright © 2012 John Wiley & Sons, Ltd.
A revised approach to discriminating sediment transport histories in glacigenic sediments in a temperate alpine environment: a case study from Fox Glacier, New Zealand
Authors: Brook Martin S. , Lukas Sven 
Published: April 2012

ABSTRACTClast shape measurements have developed into a standard method for reconstructing the transport histories of sediments in glacial environments. The majority of studies use the ‘RA‐C40’ covariance approach, with some researchers routinely including clasts of varying lithologies within their samples. The corollary is that variable lithological properties may control clast form and roundness, rather than debris‐transport mechanisms. Despite this, the role of lithology on clast shape in glacial environments has rarely been analysed. Furthermore, some studies have reported difficulties in using the RA‐C40 co‐variance plot in discriminating clasts that have undergone subglacial transport, and clasts that have been modified by fluvial activity. Results from a glacierized valley in a temperate alpine setting indicate that detailed analysis of clast shape where samples are of uniform lithology, although time consuming, is a useful tool in the investigation of deposits in glaciated environments. Copyright © 2012 John Wiley & Sons, Ltd.
Cochrane review on ‘Statins for the treatment of dementia’
Authors: McGuinness Bernadette , O'Hare John , Craig David , Bullock Roger , Malouf Reem , Passmore Peter 
Published: April 2012

ObjectivesThis review aimed to assess the clinical efficacy and tolerability of statins in the treatment of dementia.MethodsWe searched the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group, The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS, as well as many trials registries and grey literature sources (27 October 2008). Double‐blind, randomized controlled trials of statins given for at least 6 months in people with a diagnosis of dementia were included. Two independent authors extracted and assessed data independently against the inclusion criteria. Data were pooled where appropriate and entered into a meta‐analysis.ResultsThree studies were identified (748 participants, age range 50–90 years). All patients had a diagnosis of probable or possible Alzheimer's disease according to standard criteria, and most patients were established on a cholinesterase inhibitor. Change in Alzheimer's Disease Assessment Scale cognitive subscale from baseline was a primary outcome in three studies; when data were pooled, statins did not provide any beneficial effect in this cognitive measure (mean difference −1.12; 95% confidence interval −3.99, 1.75; p = 0.44). All studies provided a change in Mini‐Mental State Examination from baseline; there was no significant benefit from statins in this cognitive measure when the data were pooled (mean difference −1.53; 95% confidence interval −3.28; 0.21, p = 0.08). There were no studies identified assessing the role of statins in treatment of vascular dementia. There was no evidence that statins were detrimental to cognition.ConclusionsThere is insufficient evidence to recommend statins for the treatment of dementia. Copyright © 2012 John Wiley & Sons, Ltd.
Comparison of two modeling approaches for groundwater–surface water interactions
Authors: Guay C. , Nastev M. , Paniconi C. , Sulis M. 
Published: April 2012

AbstractAn assessment of interactions between groundwater and surface water was carried out by applying two different modeling approaches to a small‐scale study area in the municipality of Havelock, Quebec. The first approach involved a commonly used sequential procedure that consists in determining the daily recharge rate using a quasi 2D infiltration model (HELP), applied in the next step as an imposed flux to a 3D finite‐element groundwater flow model. The flow model was calibrated under steady‐state and transient conditions against measured water levels. The second approach was based on a recently developed physically based, 3D fully coupled groundwater–surface water flow model (CATHY) applied to the entire flow domain in an integrated manner. Implementation, calibration, and results of the simulations for both approaches are presented and discussed. For equal annual precipitation (1038 mm/y) and evapotranspiration (556 mm/y), the second approach computed a recharge rate of 233 mm/y (8.9% higher than the first approach) and a net upward flow from the fractured aquifer (the first approach predicted a net downward flow to the rock). The simulated annual discharge was similar for the two approaches (9.6% difference). Both approaches were found to be useful in understanding the interactions between groundwater and surface water, although limitations are apparent in the sequential procedure's inability to account for surface–subsurface feedbacks, for instance near stream reaches where groundwater discharge is prevalent. The decoupled, two‐model approach provides disaggregated surface, vadose, and aquifer flows, and a simple aperçu at the different components of total discharge. The fully coupled model accounts for continuous water exchanges between the land surface, subsurface, and stream channel in a more complex manner, and produces a better match against observed data. Copyright © 2012 John Wiley & Sons, Ltd.
Increased interaction between PACT molecules in response to stress signals is required for PKR activation
Authors: Singh Madhurima , Patel Rekha C. 
Published: April 2012

AbstractPKR (protein kinase, RNA activated) is an interferon (IFN)‐induced serine‐threonine protein kinase and is one of the key mediators in IFN's cellular actions. Although double‐stranded (ds) RNA is the most relevant PKR activator during viral infections, PACT acts as a stress‐modulated activator of PKR and is an important regulator of PKR dependent signaling pathways in the absence of viral infections. Stress‐induced phosphorylation of PACT is essential for PACT's association with PKR leading to PKR activation. PKR activation by PACT leads to phosphorylation of translation initiation factor eIF2α, inhibition of protein synthesis, and apoptosis. In the present study, we have investigated the functional significance of PACT–PACT interaction in mediating PKR activation in response to cellular stress. Our results suggest that enhanced interaction between PACT molecules when PACT is phosphorylated in response to stress signals on serines 246 and 287 is essential for efficient PKR activation. Using a point mutant of PACT that is deficient in PACT–PACT interaction, we demonstrate that PACT–PACT interaction is essential for efficient PKR activation. J. Cell. Biochem. 113: 2754–2764, 2012. © 2012 Wiley Periodicals, Inc.
Control of Catalytic Activity Via Porosity, Chemical Composition, and Morphology of Nanostructured Porous Manganese Oxide Materials
Authors: Chen Chun‐Hu , Suib Steven, L. 
Published: April 2012

AbstractThis review concerns a summary of synthesis, characterization, and applications of octahedral molecular sieve (OMS) materials. These OMS systems have been the focus of our research program for over 20 years. This review primarily covers the past 10 years with an emphasis on the most recent developments in this area. Some current areas of concern include the systematic synthesis of well ordered materials, control of particle sizes, generation of nano‐size particles, and development of new synthetic methods like pulse laser deposition and epitaxial growth of oxidic materials. Applications include use of OMS in environmental catalysis, adsorption, clean energy materials, activation of the Greenhouse gas carbon dioxide, and selective oxidations. OMS catalysts are outstanding selective oxidation catalysts and can also drive total oxidations. The highly selective of OMS systems may be related to redox cycling and redox catalysis.