bluuebunny/crossref_metadata_2025_split huggingface dataset:
“One‐pot” random terpolymerization of styrene, isoprene and butadiene with Nd‐based catalyst
Authors: Li Tingting , Hu Yanming , Zhang Hongxia , Shi Zhenghai , He Gongqiang , Wang Yurong , Shen Kaihua , Li Yang 
Published: May 2013

ABSTRACTRandom styrene‐isoprene‐butadiene rubber (SIBR) were achieved with the catalyst system composed of neodymium isopropoxide (Nd(OiPr)3), methylaluminoxane (MAO) and indene. This catalyst proved to be highly effective in cyclohexane even at low [Al]/[Nd] ratio (ca. 50) to give styrene‐rich terpolymer with high number‐average molecular weight (Mn) and narrow molecular weight distribution (Mw/Mn). Indene was critical to improve the coordination of styrene. High temperature was beneficial to increase the yield. Aliphatic solvents (hexane and cyclohexane) achieved a higher Mn of polymer than toluene as a solvent. The glass transition temperature (Tg) and composition of SIBR can be controlled by tuning the feed ratio of monomers. All the products have been fully characterized by NMR spectroscopy, gel permeation chromatograph (GPC), and DSC. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1772–1777, 2013
Influence of additive on structure of PVDF nanofibers electrospun via new spinneret design
Authors: Li Yi , Kotaki Masaya 
Published: May 2013

ABSTRACTSurface morphology and internal structure of polyvinylidene fluoride (PVDF) nanofibers were investigated in this study. PVDF nanofibers were electrospun by two types of spinnerets, nozzle and channel spinneret, with different contents of tetrabutylammonium chloride (TBAC) and at various take‐up velocities. The new spinneret design, channel spinneret, resulted in thicker fibers while high β‐phase content and smalld‐spacing were obtained, especially in the case of low TBAC content. And high TBAC content led to finer PVDF nanofibers with high β‐phase content and smalld‐spacing compared to low TBAC content regardless of spinneret types, while an increase in take‐up velocity did not have significant effect on both morphology and internal structure of PVDF nanofibers regardless of TBAC content. It suggests that electrostatic drawing acted dominantly rather than mechanically drawing in the system cooperating TBAC. However, the decreasing difference between two types of spinnerets was observed in terms of β‐phase content with an increase in TBAC content. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1752–1758, 2013
Investigation on multifunctional monomer modified polypropylene and its foamability
Authors: Zhang Wen , Yang Lili , Zhang Huaji , Lin Wei , Wang Yuexiang 
Published: May 2013

ABSTRACT1,6‐Hexanediol diacrylate (HDDA), pentaerythrithyl tetramethacrylate (PETMA), and triallyl‐isocyanurate (TAIC) were used as representative monomers to modify polypropylene (PP) in the presence of dicumyl peroxide (DCP) in a mixer. Fourier transformed infrared spectroscopy (FTIR) results confirmed that all the three polyfunctional monomers have been grafted on PP backbone. The shape of torque curves suggested the occurrence of grafting and/or crosslinking structure. The rheological behaviors of HDDA modified PP showed the highest G′ and lowest tan δ at low frequency, shear‐thinning shifted to lower frequency in η*–ω plot, as well as more deviation from semicircle characteristic of linear PP at high viscosity in Cole–Cole plot. And, the improvement of the mechanical properties followed the order as below: TAIC < PETMA < HDDA. Meanwhile, the foamability of the modified PP samples was also investigated. The cellular structure and morphology of the obtained foams were observed by scanning electron microscopy (SEM), and the results indicated that the foamability of the three modified PPs followed the same order, demonstrating HDDA modified PP foam possessed the highest cell density and expansion ratio, and the most well‐defined closed cell structure and uniformly cellular morphology. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1675–1681, 2013
Chain Folding Controlled by an Isomeric Repeat Unit: Helix Formation versus Random Aggregation in Acetylene‐Bridged Carbazole–Bipyridine Co‐Oligomers
Authors: Divya Kizhmuri P. , Sreejith Sivaramapanicker , Suresh Cherumuttathu H. , Philips Divya S. , Ajayaghosh Ayyappanpillai 
Published: May 2013

AbstractAn unprecedented, positional effect of the isomeric repeat unit on chain folding in donor–acceptor‐linked oligomers, which contain alternating bipyridine and carbazole moieties that are connected through an acetylinic linkage, is reported. 4,4′‐Linked oligomer 1 adopts an intrachain helical conformation (CD‐active) in CHCl3/MeCN (20:80 v/v), whereas oligomer 2, which contains an isomeric 6,6′‐linkage, forms interchain randomly coiled aggregates (CD‐inactive). The substitution position plays a significant role in controlling the variations in electronic effects and dipole moments around the bipyridyl moiety, which are responsible for this observed phenomenon. Two model compounds of oligomers 1 and 2 (3 and 4, respectively) were prepared and their properties were compared. A systematic investigation of the photophysical and CD properties of these structures, as well as theoretical studies, support our conclusions.
Tanycyte‐like cells form a blood–cerebrospinal fluid barrier in the circumventricular organs of the mouse brain
Authors: Langlet Fanny , Mullier Amandine , Bouret Sebastien G. , Prevot Vincent , Dehouck Benedicte 
Published: May 2013

ABSTRACTTanycytes are highly specialized ependymal cells that form a blood–cerebrospinal fluid (CSF) barrier at the level of the median eminence (ME), a circumventricular organ (CVO) located in the tuberal region of the hypothalamus. This ependymal layer harbors well‐organized tight junctions, a hallmark of central nervous system barriers that is lacking in the fenestrated portal vessels of the ME. The displacement of barrier properties from the vascular to the ventricular side allows the diffusion of blood‐borne molecules into the parenchyma of the ME while tanycyte tight junctions control their diffusion into the CSF, thus maintaining brain homeostasis. In the present work, we combined immunohistochemical and permeability studies to investigate the presence of tanycyte barriers along the ventricular walls of other brain CVOs. Our data indicate that, unlike cuboidal ependymal cells, ependymal cells bordering the CVOs possess long processes that project into the parenchyma of the CVOs to reach the fenestrated capillary network. Remarkably, these tanycyte‐like cells display well‐organized tight junctions around their cell bodies. Consistent with these observations, permeability studies show that this ependymal layer acts as a diffusion barrier. Together, our results suggest that tanycytes are a characteristic feature of all CVOs and yield potential new insights into their involvement in regulating the exchange between the blood, the brain, and the CSF within these “brain windows.” J. Comp. Neurol. 521:3389‐3405, 2013. © 2013 Wiley Periodicals, Inc.
Arachidonic acid closes innexin/pannexin channels and thereby inhibits microglia cell movement to a nerve injury
Authors: Samuels Stuart E. , Lipitz Jeffrey B. , Wang Junjie , Dahl Gerhard , Muller Kenneth J. 
Published: May 2013

ABSTRACTPannexons are membrane channels formed by pannexins and are permeable to ATP. They have been implicated in various physiological and pathophysiological processes. Innexins, the invertebrate homologues of the pannexins, form innexons. Nerve injury induces calcium waves in glial cells, releasing ATP through glial pannexon/innexon channels. The ATP then activates microglia. More slowly, injury releases arachidonic acid (ArA). The present experiments show that ArA itself reduced the macroscopic membrane currents of innexin‐ and of pannexin‐injected oocytes; ArA also blocked K+‐induced release of ATP. In leeches, whose large glial cells have been favorable for studying control of microglia migration, ArA blocked glial dye‐release and, evidently, ATP‐release. A physiological consequence in the leech was block of microglial migration to nerve injuries. Exogenous ATP (100 µM) reversed the effect, for ATP causes activation and movement of microglia after nerve injury, but nitric oxide directs microglia to the lesion. It was not excluded that metabolites of ArA may also inhibit the channels. But for all these effects, ArA and its non‐metabolizable analog eicosatetraynoic acid (ETYA) were indistinguishable. Therefore, ArA itself is an endogenous regulator of pannexons and innexons. ArA thus blocks release of ATP from glia after nerve injury and thereby, at least in leeches, stops microglia at lesions. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 621–631, 2013
A role for synaptic zinc in ProSAP/Shank PSD scaffold malformation in autism spectrum disorders
Authors: Grabrucker Andreas M. 
Published: May 2013

ABSTRACTThe establishment and maintenance of synaptic contacts as well as synaptic plasticity are crucial factors for normal brain function. The functional properties of a synapse are largely dependent on the molecular setup of synaptic proteins. Multidomain proteins of the ProSAP/Shank family act as major organizing scaffolding elements of the postsynaptic density (PSD). Interestingly, ProSAP/Shank proteins at glutamatergic synapses have been linked to a variety of Autism Spectrum Disorders (ASDs) including Phelan McDermid Syndrome, and deregulation of ProSAP/Shank has been reported in Alzheimer's disease. Although the precise molecular mechanism of the dysfunction of these proteins remains unclear, an emerging model is that mutations or deletions impair neuronal circuitry by disrupting the formation, plasticity and maturation of glutamatergic synapses. Several PSD proteins associated with ASDs are part of a complex centered around ProSAP/Shank proteins and many ProSAP/Shank interaction partners play a role in signaling within dendritic spines. Interfering with any one of the members of this signaling complex might change the output and drive the system towards synaptic dysfunction. Based on recent data, it is possible that the concerted action of ProSAP/Shank and Zn2+ is essential for the structural integrity of the PSD. This interplay might regulate postsynaptic receptor composition, but also transsynaptic signaling. It might be possible that environmental factors like nutritional Zn2+ status or metal ion homeostasis in general intersect with this distinct pathway centered around ProSAP/Shank proteins and the deregulation of any of these two factors may lead to ASDs. © 2013 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol 74: 136–146, 2014
Composition of the essential oil from the flowers of Solandra maxima (Sessé & Moc.) P.S. Green
Authors: Radoias Georges , Bosilcov Alin 
Published: May 2013

ABSTRACTDried flowers from Solandra maxima were hydrodistilled yielding 0.3% of essential oil; the yield could be slightly increased when the flowers were subjected to enzymatic hydrolysis using β‐glucosidase prior to hydrodistillation. The two samples were subjected to a comparative investigation by gas chromatography with flame ionization detection and gas chromatography–mass spectrometry. About 70 compounds were identified in both samples, representing more than 95% of the total. The main constituents were linalool (12.4% and 17.9%), methyl salicylate (9.1% and 11.4%), safranal (3.8% and 5.7%), α‐terpineol (2.0% and 4.5%), geraniol (2.6% and 3.6%), carvacrol (17.8% and 11.5%), (E)‐nerolidol (3.4% and 4.3%) and benzyl salicylate (11.1% and 7.1%). Alcohols, phenols and esters were the major classes, the concentration of alcohols being distinctly higher in the sample obtained after enzymatic hydrolysis. Copyright © 2013 John Wiley & Sons, Ltd.
Changes in sensory quality characteristics of coffee during storage
Authors: Kreuml Michaela T. L. , Majchrzak Dorota , Ploederl Bettina , Koenig Juergen 
Published: May 2013

AbstractHow long can roasted coffee beans be stored, without reducing the typical coffee flavor which is mainly responsible for consumers’ enjoyment? In Austria, most coffee packages have a best‐before date between 12 and 24 months, but it is not regulated by law. Therefore, there is the need to evaluate changes in sensory qualities of coffee beverages prepared from stored coffee beans. For preparation of the coffee beverages, the paper filter method was used. In the quantitative descriptive analysis (QDA) 10 trained assessors evaluated the intensity of 30 coffee attributes after roasting at the 9th and 18th month of storage, respectively. The sensory evaluation results showed reduction in the sensory qualities of coffee beverages after 9 months storage of roasted coffee beans. The positive associated odor and flavor attributes decreased in their intensity, whereas the negative associated odor and flavor attributes increased significantly (P < 0.05). After 18 months of storage, the rancid odor and flavor which indicate oxidation processes were even considerably perceivable. Consequently, we can assume that changes in sensory quality characteristics of roasted and vacuum‐packed coffee beans during storage are possible.
Uncertainty in future regional sea level rise due to internal climate variability
Authors: Hu Aixue , Deser Clara 
Published: May 2013

AbstractSea level rise (SLR) is an inescapable consequence of increasing greenhouse gas concentrations, with potentially harmful effects on human populations in coastal and island regions. Observational evidence indicates that global sea level has risen in the 20th century, and climate models project an acceleration of this trend in the coming decades. Here we analyze rates of future SLR on regional scales in a 40‐member ensemble of climate change projections with the Community Climate System Model Version 3. This unique ensemble allows us to assess uncertainty in the magnitude of 21st century SLR due to internal climate variability alone. We find that simulated regional SLR at mid‐century can vary by a factor of 2 depending on location, with the North Atlantic and Pacific showing the greatest range. This uncertainty in regional SLR results primarily from internal variations in the wind‐driven and buoyancy‐driven ocean circulations.
Clinical response and tumor control based on long‐term follow‐up and patient‐reported outcomes in patients with chemodectomas of the skull base and head and neck region treated with highly conformal radiation therapy
Authors: Combs Stephanie E. , Salehi–Allameh Bahar , Habermehl Daniel , Kessel Kerstin A. , Welzel Thomas , Debus Jürgen 
Published: May 2013

BackgroundThe purpose of this study was to evaluate long‐term outcome after radiation therapy (RT) for skull base or head‐and‐neck chemodectomas.MethodsWe treated 39 patients with chemodectomas with RT. Patients were treated with either single dose stereotactic radiosurgery, fractionated stereotactic radiotherapy, or intensity modulated radiotherapy (IMRT), depending on the size and anatomy of the lesion. At primary diagnosis, 16 patients were treated with surgical resection (41%), 4 with interventional embolization (10%), and 19 with primary RT (49%). Single doses of 18 Gy/80% isodose were applied. For fractionated treatments delivered as primary RT, a median total dose of 57.6 Gy was delivered. Five patients were treated with re‐irradiation, of which 4 were treated with fractionated regimens; total dose was 28.8 Gy, 30 Gy, 40 Gy, and 56 Gy in 1.8 to 2 Gy single fractions.ResultsClinical symptoms improved in 18 patients (46%), remained unchanged in 10 patients (26%), and worsening of sequelae was observed in only 1 patient, which was associated with tumor progression. Actuarial local control was 97% at 10 years. Overall survival was 89% at 5 years and 87% at 10 years. Deaths were not disease‐related except in 3 patients with tumor progression. No secondary malignancies were observed.ConclusionRT has been established as a treatment alternative for patients with glomus tumors. Long‐term local control is very high, with good clinical response to treatment. © 2013 Wiley Periodicals, Inc. Head Neck 36: 22–27, 2014
Surface water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA
Authors: Cravotta Charles A. , Goode Daniel J. , Bartles Michael D. , Risser Dennis W. , Galeone Daniel G. 
Published: May 2013

AbstractStreams crossing underground coal mines may lose flow, whereas abandoned mine drainage (AMD) restores flow downstream. During 2005–2012, discharge from the Pine Knot Mine Tunnel, the largest AMD source in the upper Schuylkill River Basin, had near‐neutral pH and elevated concentrations of iron, manganese and sulphate. Discharge from the tunnel responded rapidly to recharge but exhibited a prolonged recession compared with nearby streams, consistent with rapid infiltration of surface water and slow release of groundwater from the mine complex. Dissolved iron was attenuated downstream by oxidation and precipitation, whereas dissolved CO2degassed and pH increased. During high flow conditions, the AMD and downstream waters exhibited decreased pH, iron and sulphate with increased acidity that were modelled by mixing net‐alkaline AMD with recharge or run‐off having low ionic strength and low pH. Attenuation of dissolved iron within the river was least effective during high flow conditions because of decreased transport time coupled with inhibitory effects of low pH on oxidation kinetics.A numerical model of groundwater flow was calibrated by using groundwater levels in the Pine Knot Mine and discharge data for the Pine Knot Mine Tunnel and West Branch Schuylkill River during a snowmelt event in January 2012. Although the calibrated model indicated substantial recharge to the mine complex took place away from streams, simulation of rapid changes in mine pool level and tunnel discharge during a high flow event in May 2012 required a source of direct recharge to the Pine Knot Mine. Such recharge produced small changes in mine pool level and rapid changes in tunnel flow rate because of extensive unsaturated storage capacity and high transmissivity within the mine complex. Thus, elimination of stream leakage could have a small effect on the annual discharge from the tunnel, but a large effect on peak discharge and associated water quality downstream. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Probabilistic SWE reanalysis as a generalization of deterministic SWE reconstruction techniques
Authors: Girotto Manuela , Margulis Steven A. , Durand Michael 
Published: May 2013

AbstractSnow accumulation and melt is highly variable in space and time in complex mountainous environments. Therefore, it is necessary to provide high‐resolution spatially and temporally distributed estimates of sub‐basin snow water equivalent (SWE) to accurately predict the timing and magnitude of snowmelt runoff. In this study, we compare two reconstruction techniques (a commonly used deterministic reconstruction vs a probabilistic data assimilation framework). The methods retrospectively estimate SWE from a time series of remotely sensed maps of fractional snow‐covered area (FSCA). In testing both methods over the Tokopah watershed in the Sierra Nevada (California), the probabilistic reconstruction approach is shown to be a more robust generalization of the deterministic reconstruction. Under idealized conditions, both probabilistic and deterministic approaches perform reasonably well and yield similar results when compared with in situ verification data, whereas the probabilistic reconstruction was found to be in slightly better agreement with snow‐pit observations. More importantly, the probabilistic approach was found to be more robust: unaccounted for biases in solar radiation impacted the probabilistic SWE estimates less than the deterministic case (4% vs 7% errors for water year (WY)1997 and 0% vs 3% errors for WY1999); the probabilistic reconstruction was found to be less sensitive to the number of available observations (6% vs 10% errors in WY1997 and 13% vs 44% errors in WY1999 from the nominal cases when four fewer FSCA images were available). Finally, results from the probabilistic reconstruction approach, which requires precipitation inputs (unlike the deterministic approach), were found to be relatively robust to bias in prior precipitation estimates, where the nominal case mean estimates were recovered even when an underestimated prior precipitation was used. The additional robustness of the probabilistic SWE reconstruction technique should prove useful in future applications over larger basins and longer periods in mountainous terrain. Copyright © 2013 John Wiley & Sons, Ltd.
Reciprocal Regulation of Cyclooxygenase 2 and Heme Oxygenase 1 upon Arsenic Trioxide Exposure in Normal Human Lung Fibroblast
Authors: Wang Qisen , Wu Lijun , Wang Jun 
Published: May 2013

ABSTRACTDetoxification enzyme heme oxygenase 1 (HO‐1) and proinflammation enzyme cyclooxygenase 2 (Cox‐2) are key response proteins that function to promote the survival of cells exposed to arsenic trioxide (ATO). However, whether there is a cross‐regulation between them in ATO‐treated cells remains poorly investigated. In this study, concomitant upregulation of Cox‐2 and HO‐1 induced by ATO was observed in normal human lung fibroblasts. Cox‐2 inhibitor NS398 suppressed the upregulation of HO‐1, whereas HO‐1 inhibitor protoporphyrin IX zinc (II) stimulated the expression of Cox‐2. Both proteins were regulated by p38, and the feedback regulation of HO‐1 on Cox‐2 was mediated through p38. Our results confirmed the reciprocal regulations between Cox‐2 and HO‐1 in ATO‐treated normal cells and shed light on the understanding of protecting cells from injury caused by ATO while simultaneously decreasing the inflammation responses, which may be related to the carcinogenicity of ATO. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:323‐329, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21491
Factors controlling early stage salt tectonics at rifted continental margins and their thermal consequences
Authors: Goteti Rajesh , Beaumont Christopher , Ings Steven J. 
Published: May 2013

AbstractWe use 2‐D thermomechanical models to investigate the early evolution of rifted margin salt tectonics in terms of the competition among margin tilt, salt flow, and sediment aggradation. Model experiments include initial geometry of the rifted margin and autochthonous salt basin, subsequent synrift and thermal subsidence, sediment and water loading, and sediment compaction. We also calculate the thermal evolution of the system to investigate the impact of the high thermal conductivity of the salt (halite). Model Set 1 demonstrates a two‐phase response to salt deposition: short‐term thermal equilibration between the salt and crust and longer‐term relaxation in which the salt basin thermal image penetrates to a depth on the order of its width. Set 2 addresses the competition among margin tilt, salt flow, and sediment aggradation. Set 3 examines other factors, the salt basin width and depth, and the rifted margin width, which potentially affect the system evolution. Set 4 shows that sawtooth subsalt topography, representing faulted basement grabens, does not strongly impede salt flow. The model results are discussed in terms of a ternary diagram with apices representing tilt, salt flow, and sedimentation rates. Characteristic styles include the following: (1) tilt and rapid salt flow draining salt to the distal basin before the sediment aggrades, (2) an equivalent system with faster aggradation that captures draining salt as diapirs between minibasins, and (3) rapid sediment aggradation in which diapir‐minibasins systems develop before the salt drains. Thermal consequences of these styles are discussed. A preliminary comparison shows that salt structures resembling these styles occur in the southwest Nova Scotian margin.