bluuebunny/crossref_metadata_2025 huggingface dataset:
4‐Stufen‐Risikosimulation zur Ermittlung von Mittelabflüssen unter Berücksichtigung des geplanten Baufortschritts
Authors: Flemming Christian
Published: July 2012

Bauprojekte weisen aufgrund ihrer Komplexität, ihres zeitlichen Umfangs und ihres finanziellen Volumens ein erhebliches Risikopotenzial auf. Mit den bisherigen Methoden kann nur ein monetärer Gesamtbetrag für das Risiko eines Bauprojektes ermittelt werden. Der Auftraggeber muss aber auch die zeitliche Einordnung der Risiken berücksichtigen, um den Zeitpunkt zusätzlicher Mittelabflüsse aufgrund des Eintretens der Risiken bestimmen zu können. Auf diese Weise kann der Auftraggeber seine Finanzierungsplanung optimieren. In diesem Beitrag wird am Beispiel der Kosten für die Bauausführung gezeigt, wie die unterschiedlichen Eintrittszeitpunkte der Risiken berücksichtigt werden können, um einen zeitabhängigen Verlauf der Risikokosten und der damit verbunden Mittelabflüsse zu ermitteln.

4‐step‐risk‐simulation for the calculation of the cash outflow of the client with consideration to the scheduled construction process

Due to the complexity, the long duration and the needed scale of budget construction projects are high‐risk‐projects. The common methods can estimate a monetary value for the total risk of a construction project. Nevertheless, for the client it is important to know the date of additional cost for occurred risks to optimize his financial plan. This paper will show how the possible date of risks can be used to estimate a chronological sequence of the cash outflow.
Aktueller Planungsstand der festen Fehmarnbeltquerung – ein 18 km langer Unterwassertunnel
Authors: Morgen Karl , Hilgenstock Friedrich
Published: July 2012

Seit Mitte des 20. Jahrhunderts gibt es Überlegungen, über die Ostsee zwischen der deutschen Insel Fehmarn und der dänischen Insel Lolland eine feste Verbindung zu errichten.

Am 3. September 2008 schlossen der dänische und der deutsche Verkehrsminister einen Vertrag über die feste Querung über den Fehmarnbelt zwischen Lolland und Fehmarn.

Als einer der ersten Schritte in Richtung Realisierung der Festen Fehmarnbeltquerung wurden von zwei getrennten Planergruppen ein Brückenentwurf und ein Tunnelentwurf erstellt. Im Februar 2011 wurde der Tunnelentwurf für die weitere Entwicklung ausgewählt.

Der Tunnel mit einer Länge von 18, 1 km unter dem Meeresboden als Einschwimm‐ und Absenktunnel bildet ein einzigartiges Bauwerk. Fast 20 Mio. m3 Boden müssen aus bis zu 40 m Wassertiefe ausgehoben werden. Die standardisierten Tunnelelemente, aus denen sich der Tunnel zusammensetzt, haben Abmessungen von ca. 220 m × 42 m × 9 m. Sie sollen in einer Feldfabrik mit Trockendock hergestellt werden.

Im Beitrag soll auf die Planung, die geologischen Besonderheiten, die planungsrechtlichen Aspekte und die technischen Details des Projekts eingegangen werden.

Design status of the Fehmarnbelt Fixed Link – an 18 km long underwater tunnel

Since the middle of the last century plans were made to connect the German island of Fehmarn and the Danish island of Lolland via a fixed link.

On 3rd September 2008, the Danish and German Ministers of Transport signed a treaty to establish a fixed link across the Fehmarnbelt between Lolland and Fehmarn.

As one of the first steps towards realisation of the fixed link a bridge and an immersed tunnel option were designed by two separate groups of consultants. In February 2011, the tunnel design was selected for further development.

An immersed tunnel with a length of 18.1 km under the seabed constitutes a unique structure with a special characteristic not comparable to other tunnel projects around the world.

Almost 20 Mio. m3 soil needs to be dredged from up to 40 m water depth. The standardised tunnel elements will have dimensions of approximately 220 m × 41 m × 9 m. The elements will be produced in a purpose made production site including a launching basin.

In this article the design, the geotechnical particularities, approval aspects and technical details will be described.
Aus der Frühzeit des Betonbaus
Authors: Stiglat Klaus
Published: July 2012

Auf dem Weg vom hydraulischen Mörtel zum Stampfbeton kennzeichnen auf dem Festland nach wie vor einige Namen wichtige Streckenabschnitte: COINTEREAUX steht für die in seinen weit verbreiteten Schriften sorgfältig beschriebene Herstellung von feuerfesten ländlichen Bauten aus gestampften Erden; VICAT veranlasst mit seinem Erfolg, gezielt mit Wasserkalken “Beton” herzustellen, seinen Apologeten LEBRUN, diesen weiterzuentwickeln und bei Hochbauten und Brücken einzusetzen; COIGNET, ein Fabrikant und Chemiker, der sein ganzes Wirken und sein Lebenswerk der planmäßigen Herstellung eines Stampfbetons mit gezielten Eigenschaften erfolgreich widmet, berücksichtigt LEBRUNs Vorarbeiten lediglich in einer Fußnote. LEBRUNs Einbettung in die Geschichte des Betons verdient wegen seiner Bauwerke eine Korrektur.

From the early days of concrete construction

On the European continent, some of the important stages of development from hydraulic mortar to tamped concrete are still associated mainly with certain names: Cointereaux stands for the production of fire‐resistant, rural structures made of tamped earth that he described in his widely spread writings; through his success in using hydraulic lime to purposefully create “concrete” Vicat prompted his apologist Lebrun to continue the development and use it in buildings and bridges; Coignet, industrialist and chemist, whose entire life's work was devoted to the systemic production of tamped concrete with specific characteristics considers Lebrun's preparatory work only in a footnote. Lebrun's inclusion in the history of concrete deserves to be corrected based on the structures he built.
Hypothesis: The female excess in cranial neural tube defects reflects an epigenetic drag of the inactivating x chromosome on the molecular mechanisms of neural fold elevation
Authors: Juriloff Diana M. , Harris Muriel J.
Published: July 2012

Females have long been known to be in excess among cranial neural tube defect (NTD) cases. Up to two thirds of human anencephalics and mouse exencephalics from various genetic causes are female, but the cause of this female excess is unknown. It appears not to be attributable to gonadal hormones, developmental delay in females, or preferential death of affected males. Recent studies of the Trp53 mouse mutant showed that exencephaly susceptibility depends on the presence of two X chromosomes, not the absence of the Y. Over a decade ago, we hypothesized that the relevant difference between female and male mammalian embryos at the time of cranial neural tube closure is the fact that females methylate most of the DNA in the large inactive X chromosome after every cell division, reducing the methylation available for other needs in female cells. Recently, the Whitelaw laboratory identified several proteins in mice (Momme D genes) involved in epigenetic silencing and methylation and shared in the silencing of transgenes, retrotransposons, and the inactive‐X, and suggested that the inactive‐X acts as a “sink” for epigenetic silencing proteins. The “inactive‐X sink” hypothesis can be used to suggest expected changes in sex ratio in cranial NTDs in response to various genetic or environmental alterations. We recommend that observation of sex ratio become a standard component of all NTD studies. We suggest that the female excess among cranial NTDs is an epigenetic phenomenon whose molecular investigation will produce insight into the mechanisms underlying NTDs. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Chronic exposure to an extremely low‐frequency magnetic field induces depression‐like behavior and corticosterone secretion without enhancement of the hypothalamic–pituitary–adrenal axis in mice
Authors: Kitaoka Kazuyoshi , Kitamura Mitsuo , Aoi Shun , Shimizu Noriyuki , Yoshizaki Kazuo
Published: July 2012

An extremely low‐frequency magnetic field (ELF‐MF) is generated by power lines and household electrical devices. Many studies have suggested an association between chronic ELF‐MF exposure and anxiety and/or depression. The mechanism of these effects is assumed to be a stress response induced by ELF‐MF exposure. However, this mechanism remains controversial. In the present study, we investigated whether chronic ELF‐MF exposure (intensity, 3 mT; total exposure, 200 h) affected emotional behavior and corticosterone synthesis in mice. ELF‐MF‐treated mice showed a significant increase in total immobility time in a forced swim test and showed latency to enter the light box in a light–dark transition test, compared with sham‐treated (control) mice. Corticosterone secretion was significantly high in the ELF‐MF‐exposed mice; however, no changes were observed in the amount of the adrenocorticotropic hormone and the expression of genes related to stress response. Quantification of the mRNA levels of adrenal corticosteroid synthesis enzymes revealed a significant reduction in Cyp17a1 mRNA in the ELF‐MF‐exposed mice. Our findings suggest the possibility that high intensity and chronic exposure to ELF‐MF induces an increase in corticosterone secretion, along with depression‐ and/or anxiety‐like behavior, without enhancement of the hypothalamic–pituitary–adrenal axis. Bioelectromagnetics 34:43–51, 2013. © 2012 Wiley Periodicals, Inc.
Polypropylen‐Fasern in Hochleistungsbetonen
Authors: Pistol Klaus , Weise Frank , Meng Birgit
Published: July 2012

Bauteile bzw. Tragwerke aus Hochleistungsbetonen müssen in der Regel gegen brandinduzierte Abplatzungen mit geeigneten Maßnahmen geschützt werden, um einen ausreichenden Feuerwiderstand im Brandfall zu gewährleisten. Die bisher wirtschaftlich und technologisch sinnvollste Methode zur Verhinderung von explosionsartigen Betonabplatzungen im Brandfall ist die Zugabe von Polypropylen‐Fasern. Die Wirksamkeit der Fasern konnte zwar empirisch gezeigt werden, es stellt sich allerdings die Frage, welche Mechanismen zur Verhinderung der Abplatzungen führen. Der vorliegende Beitrag fasst bisherige Theorien zur Wirkungsweise von Polypropylen‐Fasern in brandbeanspruchten Hochleistungsbetonen zusammen und stellt eine innovative Methodologie zur Erforschung der mikrostrukturellen Prozesse vor. Die Ergebnisse zeigen, dass die nach dem Schmelzen und Zersetzen der Polypropylen‐Fasern frei werdenden Mikrokanäle durch eine gleichzeitig einsetzende Mikrorissbildung netzartig verbunden werden. Die Mikrorissbildung ermöglicht somit den Abbau von Eigen‐ und Zwangsspannungen im Beton (mechanischer Effekt) und die Entstehung eines Transportwegesystems für den ausströmenden Wasserdampf (Permeationseffekt).

Polypropylene fibres in high performance concretes. Mechanisms of action in the event of fire

Structural members and bearing structures of high performance concrete generally have to be protected against explosive spalling due to fire exposure to guarantee a sufficient fire resistance. Up to now, the economically and technologically most worthwhile method to prevent explosive spalling is the addition of polypropylene fibres. Though the effectiveness of the fibres could be shown empirically, the mechanisms preventing explosive spalling are still debatable. The present article summarizes the existing theories concerning the mode of action of polypropylene fibres in fire exposed high performance concretes and presents an innovative methodology for analysing the micro structural processes. The results show that due to the thermal decomposition of the polypropylene fibres micro channels are created and simultaneously connected due to a netlike micro crack formation. This enables the relief of internal stresses (mechanical effect) and the formation of a permeable transport system for the escaping water vapour (permeation effect).
Multicomponent Reaction to Construct Spirocyclic Oxindoles with a Michael (Triple Michael)/Cyclization Cascade Sequence as the Key Step
Authors: Li Jian , Wang Ning , Li Chunju , Jia Xueshun
Published: July 2012

Multicomponent cycloadditions with readily available isocyanides, allenoates, and isatylidene malononitriles are disclosed. This reaction, which does not require the aid of any catalyst, allows the efficient syntheses of spirocyclic oxindoles with excellent regioselectivity. Reactions with ethyl 2,3‐butadienoate and various structurally diverse α‐ and γ‐substituted allenoates are also fully explored. Remarkably, we have shown that the usual three‐component process can be further developed into an unprecedented four‐component cycloaddition in the presence of water, which provides a new strategy to access highly unusual tricyclic oxindoles. From a synthetic point of view, this protocol is very interesting considering the high level of complexity reached in one step. The mechanism is thought to proceed by a triple Michael/cyclization process by using allenoate as a three carbon atom component (3 C). Furthermore, multicomponent reaction with γ‐substituted allenoate also results in a very interesting conversion. In such cases, the unusual cleavage of the “CC” double bond of isatylidene malononitrile and one of the “CC” double bonds of allenoate is always observed.
Insights into Tris‐(2‐Hydroxylethyl)methylammonium Methylsulfate Aqueous Solutions
Authors: Aparicio Santiago , Atilhan Mert
Published: July 2012

We report herein a combined experimental–computational study on tris‐(2‐hydroxylethyl)methylammonium methylsulfate in water solutions, as a representative ionic liquid of the aqueous‐solution behavior of hydroxylammonium‐based ionic liquids. Relevant thermophysical properties were measured as a function of mixture composition and temperature. Classical molecular dynamics simulations were performed to infer microscopic structural features. The reported results for ionic liquid in water‐rich solutions show that it behaves as isolated non‐interacting ions solvated by water molecules, through well‐defined solvation shells, exerting a disrupting effect on the water hydrogen bonding network. Nevertheless, as ionic liquid concentration increase, interionic association increases, even for diluted water solutions, evolving from the typical behavior of strong electrolytes in solution toward large interacting structures. For ionic‐liquid‐rich mixtures, water exerts a minor disrupting effect on the fluid’s structuring because it occupies regions around each ion (developing water–ion hydrogen bonds) but without significantly weakening anion–cation interactions.
Mechanism of Tetralin Ring Opening and Contraction over Bifunctional Ir/SiO2‐Al2O3 Catalysts
Authors: Piccolo Laurent , Nassreddine Salim , Toussaint Guy , Geantet Christophe
Published: July 2012

The development of cleaner fuels from conventional resources requires the finding of new hydrotreatment processes able to improve the combustion performances of fuels and limit undesirable emissions. In the context of gas oil upgrading by selective ring opening, we have investigated the hydroconversion of tetralin over iridium nanoparticles supported on amorphous silica–alumina. The conversion of tetralin leads to hydrogenation, ring‐contraction, and ring‐opening products. The selectivity to ring‐opening/‐contraction products (ROCPs) increases linearly with the acid–metal site ratio and can be tuned by modifying the metal loading, the metal nanoparticle size, or the support composition. From the combination of catalytic tests at variable conversion and the products identification by two‐dimensional gas chromatography, a mechanistic reaction scheme has been established. Aromatic ROCPs are formed through purely acidic steps, whereas the formation of saturated ROCPs mostly involves bifunctional reaction steps. Iridium‐catalyzed hydrogenolysis appears to be a minor pathway with respect to iridium‐catalyzed hydrogenation and Brønsted acid catalyzed isomerization.
Utilizing Pluronic F‐127 and Gelucire 50/13 Solid Dispersions for Enhanced Skin Delivery of Flufenamic Acid
Authors: Shazly Gamal A. , Ibrahim Mohamed A. , Badran Mohamed M. , Zoheir Khairy M. A.
Published: July 2012

Strategy, Management and Health Policy

Preclinical Research

Flufenamic acid (FFA) is a nonsteroidal anti‐inflammatory drug, used in the treatment of rheumatoid arthritis, osteoarthritis, spondylitis, and other disorders. The objective of this study was to enhance the dissolution rate of the drug by the solid dispersion in the matrices of Pluronic F‐127 (PL) and Gelucire 50/13 (GL). Different drug : polymer ratios were selected for the preparation of FFA solid dispersions using solvent evaporation technique. The prepared FFA solid dispersions were characterized by differential scanning calorimetry and Fourier transform infrared spectroscopy. The dissolution study depicted that the presence of drug in solid dispersion enhances its dissolution as compared with the drug itself and the drug : polymer ratio 1:1 was superior in enhancing FFA dissolution rate from solid dispersions. The in vitro skin permeation from Carbopol 940 gel base through abdominal rat skin membranes was investigated. The data showed that FFA‐PL followed by FFA‐GL solid dispersion enhanced drug permeation through rat skin, while untreated drug showed slower permeation. Furthermore, FFA in its PL and GL solid dispersions exhibited a potent local anti‐inflammatory activity against formalin‐induced paw edema from Carbopol gel base compared with the untreated drug, and this activity reached its peak (96% and 84%, respectively) after 4 h.
Long‐term flavor recognition in humans with prenatal garlic experience
Authors: Hepper Peter G. , Wells Deborah L. , Dornan James C. , Lynch Catherine
Published: July 2012

The human fetus learns about its chemosensory environment and this influences its behavior at birth and during the nursing period. This study examined whether prenatal experience could influence behavior much later in life. The dietary preference of two groups of children (8‐ to 9‐years old) was examined. Mothers of one group had consumed garlic during pregnancy, mothers of the control group had not. Children received two tests, 1 month apart, of a meal containing two portions of potato gratin, one flavored with garlic. The total amount of potato, and the percentage of garlic flavored potato, eaten was calculated and examined separately by ANOVA for factors of prenatal exposure, the child's sex, and trial. Children prenatally exposed to garlic ate significantly more garlic flavored potato and a significantly greater overall amount of potato on trial 2, compared to controls. The results demonstrate prenatal experience may affect behavior well into childhood. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 568–574, 2013
Intersections between development and evolution in the classification of emotions
Authors: Clark Jason A.
Published: July 2012

In this article, I use the example of emotions to illustrate how various concepts of homology can play a role in developmental psychology by showing how developmental and evolutionary approaches to the classification of psychological traits complement and constrain one another. In order to do this I argue against the “Standard Model” of emotional classification according to which basic and higher cognitive emotions belong to radically different classes of emotions. Neither developmental nor evolutionary considerations support the Standard Model, and a combined ontogenetic and phylogenetic approach presents a stronger case for the revision of this model than does either of these taken alone. Recent attempts to integrate developmental and evolutionary factors in the explanation of other psychological traits can guide research in these areas. I argue that a consideration of various neglected forms of homology that are closely tied to development resolves some outstanding problems in ontogenetic and phylogenetic classification of emotion. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 67–75, 2013.
Commentaries on ‘Nebulized epinephrine for croup in children’
Authors: Bressan Silvia , Baraldi Eugenio , Bregstein Joan , Pusic Martin
Published: July 2012

These are commentaries on a Cochrane review, published in this issue of EBCH, first published as: Bjornson C, Russell KF, Vandermeer B, Durec T, Klassen TP, Johnson DW. Nebulized epinephrine for croup in children. Cochrane Database of Systematic Reviews 2011, Issue 2. Art. No.: CD006619. DOI: 10.1002/14651858.CD006619.pub2

Further information for this Cochrane review is available in this issue of EBCH in the accompanying Summary article. Copyright © 2012 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
Commentaries on ‘Pharmacological treatment for Attention Deficit Hyperactivity Disorder (ADHD) in children with comorbid tic disorders’
Authors: Bloch Michael H. , Gorman Daniel A. , Abi‐Jaoude Elia
Published: July 2012

These are commentaries on a Cochrane review, published in this issue of EBCH, first published as: Pringsheim T, Steeves T. Cochrane Database of Systematic Reviews 2011, Issue 4. Art. No.: CD007990. DOI: 10.1002/ 14651858.CD007990.pub2

Further information for this Cochrane review is available in this issue of EBCH in the accompanying Summary article. Copyright © 2012 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
Waterfalls drive parallel evolution in a freshwater goby
Authors: Kano Yuichi , Nishida Shin , Nakajima Jun
Published: July 2012

Waterfalls may affect fish distribution and genetic structure within drainage networks even to the extent of leading evolutionary events. Here, parallel evolution was studied by focusing on waterfall and the landlocked freshwater goby Rhinogobius sp. YB (YB), which evolved from amphidromous R. brunneus (BR). The fish fauna was surveyed at 30 sites in 11 rivers on Iriomote Island, Japan, the geography of which was characterized by terraces/tablelands with many waterfalls. We found that all YB individuals were distributed only above waterfalls (height 6.8–58.7 m), whereas BR, and other fishes, were mostly distributed below waterfalls. Mitochondrial DNA analysis showed that every YB local population above the waterfall was independently evolved from BR. In contrast, cluster analysis of nine morphological characters, such as fin color and body pattern, showed that the morphology of YB individuals held a similarity beyond the genetic divergence, suggesting parallel evolution has occurred relating to their morphology. Genetic distance between each YB local population and BR was significantly correlated with waterfall height (r2 = 0.94), suggesting that the waterfalls have been heightened due to the constant geological erosion and that their height represents the isolation period of YB local populations from BR (ca. 11,000–88,000 years). Each local population of BR was once landlocked in upstream by waterfall formation, consequently evolving to YB in each site. Although the morphology of YB had a high degree of similarity among local populations, finer scale analysis showed that the morphology of YB was significantly correlated with the genetic distance from BR. Consequently, there could be simultaneous multiple phases of allopatric/parallel evolution of the goby due to variations in waterfall height on this small island.
Shifts in species richness, herbivore specialization, and plant resistance along elevation gradients
Authors: Pellissier Loïc , Fiedler Konrad , Ndribe Charlotte , Dubuis Anne , Pradervand Jean‐Nicolas , Guisan Antoine , Rasmann Sergio
Published: July 2012

Environmental gradients have been postulated to generate patterns of diversity and diet specialization, in which more stable environments, such as tropical regions, should promote higher diversity and specialization. Using field sampling and phylogenetic analyses of butterfly fauna over an entire alpine region, we show that butterfly specialization (measured as the mean phylogenetic distance between utilized host plants) decreases at higher elevations, alongside a decreasing gradient of plant diversity. Consistent with current hypotheses on the relationship between biodiversity and the strength of species interactions, we experimentally show that a higher level of generalization at high elevations is associated with lower levels of plant resistance: across 16 pairs of plant species, low‐elevation plants were more resistant vis‐à‐vis their congeneric alpine relatives. Thus, the links between diversity, herbivore diet specialization, and plant resistance along an elevation gradient suggest a causal relationship analogous to that hypothesized along latitudinal gradients.
Increased cold and heat pain thresholds influence the thermal grill illusion in schizophrenia
Authors: Boettger M.K. , Grossmann D. , Bär K‐J.
Published: July 2012

Background

Patients with schizophrenia show decreased sensitivity towards clinical and experimental painful conditions. To date, the exact underlying mechanisms are not completely understood. One method to examine central integrative processes of pain perception is the thermal grill illusion (TGI), in which interlacing cold and warm bars create the illusion of a painful sensation.

Methods

In 18 unmedicated patients with acute paranoid schizophrenia, cold and heat pain thresholds (CPT/HPT) as well as the perception of the TGI were examined and compared to 18 matched controls. In addition, symptom scales were obtained in order to relate pain perception to psychopathology.

Results

CPT and HPT were significantly increased in patients compared to controls. In the range of TGI stimuli that were perceived painful by controls, patients did not indicate painful sensations, instead the stimulus response curve of TGI pain perception was shifted towards higher stimulus intensities, i.e., greater temperature differentials between cold and warm bars. This increase was comparable to that seen in CPT and HPT. There was no association with psychopathology for any pain parameter.

Conclusions

CPT and HPT, as well as temperature differentials for the perception of the TGI were increased in patients with schizophrenia as compared to controls. Similar to visual illusions, in which reduced contrast sensitivity has been shown to alter the perception of illusions, the discriminatory somatosensory deficit, which is reflected in higher CPT and HPT as well as the previously reported increased warmth perception thresholds, might account for the attenuation of TGI in patients.
Ultraviolet A regulates the stemness of human adipose tissue‐derived mesenchymal stem cells through downregulation of the HIF‐1α via activation of PGE2–cAMP signaling
Authors: Lee Jongsung , Jung Eunsun , Hyun Jin‐Won , Park Deokhoon
Published: July 2012

Ultraviolet A (UVA) irradiation is responsible for a variety of changes in cell biology. The purpose of this study was to investigate the effects of UVA irradiation on the stemness properties of human adipose tissue‐derived mesenchymal stem cells (hAMSCs). Furthermore, we examined the UVA‐antagonizing effects of L‐cysteine ethylester hydrochloride (ethylcysteine) and elucidated its action mechanisms. The results of this study showed that UVA reduced the proliferative potential and stemness of hAMSCs, as evidenced by reduced proliferative activity in the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay and downregulation of OCT4, NANOG, and SOX2, stemness‐related genes. The mRNA level of hypoxia‐inducible factor (HIF)‐1α, but not HIF‐2α was reduced by UVA. Moreover, the knockdown of HIF‐1α using small interfering RNA (siRNA) for HIF‐1α was found to downregulate stemness genes, suggesting that UVA reduces the stemness through downregulation of HIF‐1α. In addition, we examined the mechanisms underlying the UVA‐mediated effects and found that UVA induced production of prostaglandin (PG) E2 and 3′‐5′‐cyclic adenosine monophosphate (cAMP), and that this effect was mediated through activation of activating protein‐1 (AP‐1) and nuclear factor‐κB (NF‐κB). The UVA effects were antagonized by ethylcysteine, and the effects were found to be mediated by reduced production of PGE2 through the inhibition of JNK and p42/44 MAPK. Taken together, these findings show for the first time that UVA regulates the stemness of hAMSCs and its effects are mediated by downregulation of HIF‐1α via the activation of PGE2–cAMP signaling. In addition, ethylcysteine may be used as an antagonizing agent to mitigate the effects of UVA. J. Cell. Biochem. 113: 3681–3691, 2012. © 2012 Wiley Periodicals, Inc.
CHOP down‐regulates cFLIPL expression by promoting ubiquitin/proteasome‐mediated cFLIPL degradation
Authors: Noh Hyo‐Jeong , Lee Sung‐Jun , Sung Eon‐Gi , Song In‐Hwan , Kim Joo‐Young , Woo Chang‐Hoon , Kwon Taeg Kyu , Lee Tae‐Jin
Published: July 2012

The transcription factor CHOP/GADD153 is induced during the unfolded protein response and is related to the induction of ER stress‐mediated apoptosis. However, how CHOP is organized between the pro‐survival and pro‐apoptotic roles of ER stress remains largely undefined. In this study, we identified the apoptosis regulating protein suppressed by CHOP. We found that treatment of Caki cells with CHOP‐inducing drugs including withaferin A, thapsigargin, brefeldin A, and silybin led to a strong reduction in cFLIPL protein levels together with a concomitant increase in the CHOP protein. Interestingly, Wit A down‐regulated cFLIPL expression via both suppressing mRNA transcription and increasing cFLIPL protein instability. We also found that forced expression of CHOP dose‐dependently led to a decrease of cFLIPL protein expression but did not alter cFLIPL mRNA levels. Additionally, we observed that siRNA‐mediated CHOP silencing recovered the cFLIPL expression decreased by CHOP‐inducing agents in Caki cells. Finally, we showed that CHOP facilitates ubiquitin/proteasome‐mediated cFLIPL degradation, leading to down‐regulation of cFLIPL. Finally, cFLIPL over‐expression reduced cell death induced by treatment with brefeldin A, thapsigargin, and silybin. Taken together, our results provide novel evidence that cFLIPL is a CHOP control target and that CHOP‐induced down‐regulation of cFLIPL is due to activation of the ubiquitin/proteasome pathways. J. Cell. Biochem. 113: 3692–3700, 2012. © 2012 Wiley Periodicals, Inc.
β‐hexosaminidase from Xenopus laevis eggs and oocytes: From gene to immunochemical characterization
Authors: Morales Enrique S. , Krapf Darío , Botta Pablo E. , Cabada Marcelo O. , Arranz Silvia E.
Published: July 2012

Glycosidases are present both in sperm and eggs in vertebrates and have been associated with different fertilization steps as gamete binding, egg coat penetration, and polyspermy prevention. In this manuscript, we have analyzed the activity of different glycosidases of Xenopus laevis eggs. The main activity corresponded to N‐acetyl‐β‐D‐glucosaminidase (Hex), which was reported to participate both in gamete binding and polyspermy prevention among phylogenetically distant animals. We have raised homologous antibodies against a recombinant N‐terminal fragment of a X. laevis Hex, and characterized egg's Hex both by Western blot and immunohistochemical assays. Noteworthy, Hex was mainly localized to the cortex of animal hemisphere of full‐grown oocytes and oviposited eggs, and remained unaltered after fertilization. Hex is constituted by different pair arrangements of two subunits (α and β), giving rise to three possible Hex isoforms: A (αβ), B (ββ), and S (αα). However, no information was available regarding molecular identity of Hex in amphibians. We present for the first time the primary sequences of two isoforms of X. laevis Hex. Interestingly, our results suggest that α‐ and β‐like subunits that constitute Hex isoforms could be synthesized from a same gene in Xenopus, by alternative exon use. This finding denotes an evolutionary divergence with mammals, where α and β Hex subunits are synthesized from different genes on different chromosomes. J. Cell. Biochem. 113: 3709–3720, 2012. © 2012 Wiley Periodicals, Inc.
Quantifying Utricular Stimulation During Natural Behavior
Authors: RIVERA ANGELA R. V. , DAVIS JULIAN , GRANT WALLY , BLOB RICHARD W. , PETERSON ELLENGENE , NEIMAN ALEXANDER B. , ROWE MICHAEL
Published: July 2012

The use of natural stimuli in neurophysiological studies has led to significant insights into the encoding strategies used by sensory neurons. To investigate these encoding strategies in vestibular receptors and neurons, we have developed a method for calculating the stimuli delivered to a vestibular organ, the utricle, during natural (unrestrained) behaviors, using the turtle as our experimental preparation. High‐speed digital video sequences are used to calculate the dynamic gravito‐inertial (GI) vector acting on the head during behavior. X‐ray computed tomography (CT) scans are used to determine the orientation of the otoconial layer (OL) of the utricle within the head, and the calculated GI vectors are then rotated into the plane of the OL. Thus, the method allows us to quantify the spatio‐temporal structure of stimuli to the OL during natural behaviors. In the future, these waveforms can be used as stimuli in neurophysiological experiments to understand how natural signals are encoded by vestibular receptors and neurons. We provide one example of the method, which shows that turtle feeding behaviors can stimulate the utricle at frequencies higher than those typically used in vestibular studies. This method can be adapted to other species, to other vestibular end organs, and to other methods of quantifying head movements. J. Exp. Zool. 317A:467‐480, 2012. © 2012 Wiley Periodicals, Inc.
Non‐destructive measurement of vitamin C, total polyphenol and sugar content in apples using near‐infrared spectroscopy
Authors: Pissard Audrey , Fernández Pierna Juan A , Baeten Vincent , Sinnaeve Georges , Lognay Georges , Mouteau Anne , Dupont Pascal , Rondia Alain , Lateur Marc
Published: July 2012

BACKGROUND: The vitamin C and polyphenol content of apples constitute quality and nutritional parameters of great interest for consumers, especially in terms of health. They are commonly measured using laborious reference methods. The purpose of this study was to evaluate the potential of near‐infrared (NIR) spectroscopy as a rapid and non‐destructive method to determine the sugar, vitamin C and total polyphenol content in apples.

RESULTS: The quality parameters of more than 150 apple genotypes were analyzed using NIR and reference methods. The results obtained using the least squares support vector machine regression method showed good to very good prediction performance. Low standard error of prediction values, in addition to relatively high ratio to prediction (RPD) values, demonstrated the precision of the models, especially for polyphenol and sugar content. High RPD values (5.1 and 4.3 for polyphenol and sugar, respectively) indicated that an accurate classification of apples based on their content could be achieved.

CONCLUSION: NIR spectroscopy coupled with the multivariate calibration technique could be used to accurately measure the quality parameters of apples. In addition, in the case of breeding programs, NIR spectroscopy can be considered an interesting tool for sorting varieties according to a range of concentrations. Copyright © 2012 Society of Chemical Industry
Enantioselective determination of acylamino acid fungicides in vegetables and fruits by chiral liquid chromatography coupled with tandem mass spectrometry
Authors: Zhang Hu , Wang Xinquan , Jin Lixia , Qian Mingrong , Wang Xiangyun , Xu Hao , Qi Peipei , Wang Qiang , Wang Minghua
Published: July 2012

An efficient and sensitive enantioselective method for simultaneous determination of three acylamino acid fungicides in vegetables and fruits was presented by high‐performance liquid chromatography (HPLC) coupled with tandem mass spectrometry. The three fungicides (benalaxyl, furalaxyl, and metalaxyl) residues in samples were extracted with acetonitrile containing 1% acetic acid and an aliquot was cleaned up with Si‐(CH2)3‐NH‐(CH2)2‐NH2 and C18 sorbent. Complete enantioseparation of three acylamino acid fungicides enantiomers was obtained under reversed‐phase conditions on a cellulose tris (4‐chloro‐3‐methylphenylcarbamate) column at 25°C using acetonitrile–0.1% formic acid solution (45:55, v/v) as a mobile phase. The elution orders of the eluted enantiomers were determined by a circular dichroism (CD) detector. The linearity, matrix effect, recovery, and precision were evaluated. Good linearity was obtained over the concentration range of 0.5–250 μg/L for each enantiomer in the standard solution and sample matrix calibration curves. There was no significant matrix effect for three fungicides determination based on the method. The inter‐day mean recoveries, intra‐day repeatability, and inter‐day reproducibility varied from 81.3 to 95.7%, 2.2 to 9.4%, and 2.3 to 9.6%, respectively. The method provided high selectivity and sensitivity, and limits of quantification for enantiomers of three fungicides in vegetables and fruits were both 1 μg/kg.
Reverse micelle‐mediated dispersive liquid–liquid microextraction of 2,4‐dichlorophenoxyacetic acid and 4‐chloro‐2‐methylphenoxyacetic acid
Authors: Tayyebi Moslem , Yamini Yadollah , Moradi Morteza
Published: July 2012

A supramolecular solvent consisting of reverse micelles of decanoic acid, dispersed in a continuous phase of tetrahydrofuran:water, was proposed as an efficient microextraction technique for extraction of selected chlorophenoxy acid herbicides from water samples prior to high‐performance liquid chromatography UV determination. The disperser solvent (1.0 mL tetrahydrofuran) containing 20 mg decanoic acid was rapidly injected into 10.0 mL of water sample. After centrifugation, the reverse micelle‐rich phase (25 ± 0.5 μL) was floated at top of the home‐designed centrifuge tube. The solvent was collected and 20 μL of it was injected into high‐performance liquid chromatography for analysis. The results showed that the in situ solvent formation and extraction process can be completed in a few seconds. Under the optimal conditions, limits of detection of the method for 4‐chloro‐2‐methylphenoxyacetic acid and 2,4‐dichlorophenoxyacetic acid were in the range of 0.5–0.8 μg L−1 and the repeatability of the proposed method, expressed as relative standard deviation, varied in the range of 2.5–3.2%. Linearity was found to be in the range of 1–200 μg L−1 and the preconcentration factors were between 148 and 157. The mean percentage recoveries exceeded 92.0% for all the spiking levels in real water samples.
Purification of polyclonal antibodies from Cohn fraction II + III, skim milk, and whey by affinity chromatography using a hexamer peptide ligand
Authors: Menegatti Stefano , Naik Amith D. , Gurgel Patrick V. , Carbonell Ruben G.
Published: July 2012

HWRGWV, a peptide that binds specifically to the Fc fragment of human immunoglobulin G (IgG), was used for the purification of IgG from Cohn fraction II + III of human plasma and from bovine skim milk and whey. The concentration of sodium chloride and sodium caprylate in the binding buffer as well as the pH of the elution buffer were optimized to achieve high IgG yield and purity. Under optimized conditions, IgG was recovered from plasma fractions with yield and purity up to 84% and 95%, respectively. IgG was also purified from skim milk with 74% yield and 92% purity and from whey with 85% yield and 93% purity. Purification experiments were also performed with Protein A resin and the results were found to be similar to those obtained with the peptide adsorbent.
Determination of rifaximin in rat serum by ionic liquid based dispersive liquid–liquid microextraction combined with RP‐HPLC
Authors: Nageswara Rao Ramisetti , Mastan Vali Rajavarapu , Vara Prasada Rao Alamanda
Published: July 2012

An efficient and environmental friendly ionic liquid based dispersive liquid–liquid microextraction procedure was optimized for determination of rifaximin in rat serum by reverse phase high‐performance liquid chromatography. The effect of ionic liquids, dispersive solvents, extractant/disperser ratio, and salt concentrations on sample recovery and enrichment factors were studied. Among the five ionic liquids studied in the present investigation, 1‐butyl‐3‐methylimidazolium hexafluorophosphate was found to be most effective for extraction of rifaximin. The recovery was found to be more than 98% using 1‐butyl‐3‐methylimidazolium hexafluorophosphate and methanol as extraction and dispersive solvents, at an extractant/disperser ratio of 0.43. The recovery was further enhanced to 99.5% by the addition of 5.0% NaCl solution. A threefold enhancement in detection limit was achieved when compared to protein precipitation. The ionic liquid containing the extracted rifaximin was directly injected into HPLC system. The linear relationship was observed in the range of 0.03–10.0 μg/mL with the correlation coefficient (r2) 0.9998. Limits of detection and quantification were found to be 0.01 and 0.03 μg/mL, respectively. The relative standard deviation was 2.5%. The method was validated and applied to study pharmacokinetics of rifaxmin in rat serum.
Separation of peptides with an aqueous mobile phase by temperature‐responsive chromatographic column
Authors: Liu Zongjian , Liang Yanli , Geng Fangfang , Ge Chen , Ullah Kaleem , Lv Fang , Dai Rongji , Zhang Yukui , Deng Yulin
Published: July 2012

Peptide separation technology is significant and is still an analytical challenge in proteomic studies. We report a simple preparation method for poly(N‐isopropylacrylamide) grafted silica through the copolymerization of N‐isopropylacrylamide with acetyl moieties immobilized on the silica surfaces. Differential scanning calorimetry results indicated that the prepared silica exhibited a sharp phase transition at 35.03°C. Silica grafted with poly(N‐isopropylacrylamide) was evaluated as a temperature‐responsive chromatography medium for the separation of peptides using 0.2 M NaCl solution as a mobile phase. Results indicated that at 10°C, the peptides were not resolved, but baseline separation with prolonged retention time at 50°C was attained. Particularly, a mixture of four peptides was efficiently separated within 8 min. The theoretical plate number of every peptide was more than 2500, and the resolutions were more than 3.40. The increased selectivity of the temperature‐responsive column resulted from the temperature‐modulated hydrophobic interaction with peptides. The retention times of these peptides were related to their hydrophobicities. This protocol provided a reliable set of chromatographic tool usable across all research and development applications that required isolation and analysis of peptides. It may represent a step forward in the complex analysis of hydrophobic and other proteins.
Separations using a porous‐shell pillar array column on a capillary LC instrument
Authors: Malsche Wim De , Bruyne Selm De , Beeck Jeff Op De , Eeltink Sebastiaan , Detobel Frederik , Gardeniers Han , Desmet Gert
Published: July 2012

We investigated the achievable separation performance of a 9‐cm‐long and 1‐mm‐wide pillar array channel (volume = 0.6 μL) containing 5 μm diameter Si pillars (spacing 2.5 μm) cladded with a mesoporous silica layer with a thickness of 300 nm, when this channel is directly interfaced to a capillary LC instrument. The chip has a small footprint of only 4 cm × 4 mm and the channel consists of three lanes that are each 3 cm long and that are interconnected using low dispersion turns consisting of a narrow U‐turn (10 μm), proceded and preceded by a diverging flow distributor. Measuring the band broadening within a single lane and comparing it to the total channel band broadening, the additional band broadening of the turns can be estimated to be of the order of 0.5 μm around the minimum of the van Deemter curve, and around some 1 μm (nonretained species) and 2 μm (retained species) in the C‐term dominated regime. The overall performance (chip + instrument) was evaluated by conducting gradient elution separations of digests of cytochrome c and bovine serum albumin. Peak capacities up to 150 could be demonstrated, nearly completely independent of the flow rate.
Effects of ligand density and pore size on the adsorption of bovine IgG with DEAE ion‐exchange resins
Authors: Lu Hui‐Li , Lin Dong‐Qiang , Zhu Mi‐Mi , Yao Shan‐Jing
Published: July 2012

Immunoglobulin G is an important plasma protein with many applications in therapeutics and diagnostics, which can be purified effectively by ion exchange chromatography. The ligand densities and pore properties of ion‐exchange resins have significant effects on the separation behaviors of protein, however, the understandings are quite limited. In this work, with bovine immunoglobulin as the model IgG, the adsorption isotherms and adsorption kinetics were investigated systematically with series of diethylaminoethyl ion‐exchange resins with different ligand densities and pore sizes. The Langmuir equation and pore diffusion model were used to fit the experimental data. The influences of ligand density and pore size on the saturated adsorption capacity, the dissociation constant and the effective diffusivity were discussed. The adsorption capacities increased with the increase of ligand density and the decrease of pore size, and an integrative parameter was proposed to describe the combined effects of ligand density and pore size. It was also found that the effective pore diffusion coefficient of the adsorption kinetics was influenced by pore sizes of resins, but was relatively independent on the ligand densities of resins. For a given protein, the ligand density and pore size should be optimized for improving the protein adsorption.
UPLC–MS/MS performing pharmacokinetic and biodistribution studies of rhein
Authors: Sun Hui , Yin Quanwei , Zhang Aihua , Wang Xijun
Published: July 2012

Rhein, an important constituent of Radix et Rhizoma Rhei, has been used to alleviate liver and kidney damage. In this work, plasma pharmacokinetic and biodistribution characteristics of rhein after oral administration was investigated using a rapid and sensitive ultra‐performance liquid chromatography coupled to tandem high‐definition mass spectrometry (UPLC–MS/MS) method. Mass spectrometry was performed on a Waters Micromass high‐definition technology with an electrospray ionization source in positive ion mode. Biosamples were prepared using methanolic precipitation and the separation of rhein was achieved on a UPLC HSS T3 column by linear gradient elution and the total run time was only 4.70 min. Data were analyzed and estimated by compartmental methods using WinNonlin Professional version 5.1. Mean pharmacokinetic parameters following single‐dose administration of rhein was consistent with a two‐compartmental open model. It was found that rhein was distributed and eliminated rapidly in rats and the biodistribution showed the higher levels were in liver, spleen, kidney, heart, lung and the lower level observed in the muscle, adrenal, and thyroid. It was not discovered in brain and showed that rhein could not cross the blood–brain barrier. Our developed UPLC–MS/MS approach was capable of providing complete pharmacokinetic and biodistribution parameters for rhein when administered orally.