bluuebunny/crossref_metadata_2025_split huggingface dataset:
The impact of pH control on the volumetric productivity of mixed culture PHA production from fermented molasses
Authors: Oehmen Adrian , Pinto Fátima V. , Silva Vera , Albuquerque Maria G. E. , Reis Maria A. M. 
Published: October 2013

Polyhydroxyalkanoate (PHA) production via mixed microbial cultures (MMCs) can potentially decrease process operational costs as compared to conventional pure culture techniques. However, the volumetric productivity of PHA by MMCs must be augmented to increase its cost competitiveness. For this purpose, a three‐stage bioreactor system was operated in this study, with (i) anaerobic fermentation of molasses, (ii) culture selection, and (iii) PHA accumulation and harvesting stages. In stage 2, bioreactor operation with pH control at 8 led to twice the biomass concentration (up to 8 g VSS L−1, where VSS is the volatile suspended solids) as compared to operation without pH control (maximum pH 9). No loss in the specific PHA storage efficiency was observed (PHA content up to 57.5% and PHA storage rate up to 0.27 Cmol PHA Cmol X−1 h−1, where X is the active biomass), thereby resulting in twice the volumetric PHA production rate. The limited biomass growth at the higher pH level was not due to nutrient limitation, but likely to a shift in the microbial community. It is hypothesized that the increased enrichment of Azoarcus at pH 8 led to higher PHA productivity. pH control in the culture selection stage can lead to enhanced PHA production from MMCs, improving the viability of the process.
Visualization tools for assessing the Markov property: sojourn times in the forest Fire Weather Index in Ontario
Authors: Albert‐Green Alisha , John Braun W. , Martell David L. , Woolford Douglas G. 
Published: October 2013

AbstractIn Canada, the Fire Weather Index (FWI) provides forest fire managers with an overall measure of fire danger. Specifically, the FWI is a numerical rating of the potential intensity of a forest fire based on its potential spread rate and the amount of vegetation available for combustion. In our analyses, we consider daily FWI time series, recorded over 42 fire seasons from a sample of fire‐weather stations in Ontario, Canada. Graphical exploratory analyses of the data, including stalagmite plots (a new interactive, three‐dimensional visualization tool), show that the FWI switches between epochs of nil and non‐nil behaviour. This paper develops a framework for assessing sojourn times in these two phases. At some sites, the FWI process appears to begin each year as an approximate Markov process before gradually losing its Markovian character. However, a time‐homogeneous discrete time Markov chain model is insufficient overall, because those sojourn times are not found to be geometrically distributed. Instead, the duration of epochs in each of these phases can be more accurately modelled using beta‐geometric random variables which incorporate seasonality of phase‐specific run length behaviour using local likelihood methods. Copyright © 2013 John Wiley & Sons, Ltd.
Antioxidant assays – consistent findings from FRAP and ORAC reveal a negative impact of organic cultivation on antioxidant potential in spinach but not watercress or rocket leaves
Authors: Payne Adrienne C. , Mazzer Alice , Clarkson Graham J. J. , Taylor Gail 
Published: October 2013

AbstractWatercress (Rorippa nasturtium‐aquaticum), wild rocket (Diplotaxis tenuifolia), and spinach (Spinacia oleracea) are commercial crops reported to have high concentrations of antioxidants, possibly contributing to disease prevention following human consumption. Following analysis of supermarket‐purchased salad leaves, we report the antioxidant content potential of these species using two comparable techniques assessing the consistency between the assays – by the ferric reducing antioxidant power (FRAP) assay and the oxygen radical absorbance capacity (ORAC) assay. The leaves were harvested from both conventionally and organically managed crops, to investigate whether organic agriculture results in improved crop quality. Watercress had the highest FRAP and ability to scavenge free radicals, followed by spinach and rocket. For watercress and rocket, there was no significant effect of organic agriculture on FRAP and ORAC, but for spinach, the antioxidant potential was reduced and this was significant at the 5% level of probability for FRAP but not ORAC, although the trend was clear in both tests. We conclude that there is variation in salad crop antioxidant potential and that FRAP and ORAC are useful techniques for measuring antioxidants in these salad crops with similar ranking for each salad crop studied.
Improved protocols for vibrational spectroscopic analysis of body fluids
Authors: Bonnier Franck , Petitjean François , Baker Matthew J. , Byrne Hugh J. 
Published: October 2013

AbstractThe applications of vibrational spectroscopy to the examination of human blood serum are explored. Although FTIR spectra can be recorded in aqueous solutions at (gelatin) concentrations as low as 100 mg/L, the high‐wavenumber region remains obscured by water absorption. Using Raman spectroscopy, high quality spectra of gelatine solutions as low as 10 mg/L can be achieved, also covering the high‐wavenumber regions. In human serum, spectral profiles are weak and partially obscured by water features. Dried deposits are shown to be physically and chemically inhomogeneous resulting in reduced measurement reproducibility. Concentration of the serum using commercially available centrifugal filter devices results in an improvement in the spectral intensity and quality. Additionally, in Raman spectroscopy, reduced background and significantly enhanced signal collection is achievable by measurement in an inverted geometry. The improved protocols for spectroscopic measurement of human serum are applicable to a range of bodily fluids and should accelerate potential clinical applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Waveguide evanescent field scattering microscopy: bacterial biofilms and their sterilization response via UV irradiation
Authors: Nahar Qamrun , Fleißner Frederik , Shuster Jeremiah , Morawitz Michael , Halfpap Christopher , Stefan Mihaela , Langbein Uwe , Southam Gordon , Mittler Silvia 
Published: October 2013

AbstractWaveguide Evanescent Field Scattering (WEFS) microscopy is introduced as a new and simple tool for label‐free, high contrast imaging of bacteria and bacteria sensors. Bacterial microcolonies and single bacteria were discriminated both by their bright field images and by their evanescent scattering intensity. By comparing bright field images with WEFS images, the proportion of planktonic: sessile (i.e., “floating”: attached) bacteria were measured. Bacteria were irradiated with UV light, which limited their biofilm forming capability. A quantitative decrease in attachment of individual, sessile bacteria and in attached, microcolony occupied areas was easily determined within the apparent biofilms with increasing UV dose. WEFS microscopy is an ideal tool for providing rapid quantitative data on biofilm formation. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of hyaluronic acid on biofunctionality of gelatin–collagen intestine tissue engineering scaffolds
Authors: Shabafrooz Vahid , Mozafari Masoud , Köhler Gerwald A. , Assefa Senait , Vashaee Daryoosh , Tayebi Lobat 
Published: October 2013

AbstractThe creation of engineered intestinal tissue has recently stimulated new endeavors with the ultimate goal of intestinal replacement for massive resections of bowel. In this context, we investigated the effect of hyaluronic acid (HA) on the physicochemical characteristics of gelatin–collagen scaffolds and its cytocompatibilty to the human intestinal epithelial Caco‐2 cell line in vitro. Gelatin/collagen hybrid scaffolds with different concentrations of HA were prepared by solvent casting and freeze‐drying techniques and subsequent chemical crosslinking by genipin. The morphologies of the scaffolds were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. In vitro tests were carried out in phosphate‐buffered saline (PBS) solution to study the swelling ratio and the biostability of the scaffolds. It was found that the porous structure of the scaffolds could be tailored by further addition of HA. Moreover, both the swelling ratio and the degradation rate of the scaffold increased by addition of HA. A resazurin‐based cell viability assay was employed to determine the viability and estimate the number of scaffold‐adherent Caco‐2 cells. The assay indicated that the scaffolds were all cytocompatible. We concluded that addition of less than 15% HA to scaffolds with a composition of 9:1 gelatin:collagen results only in incremental improvement in the structural characteristics and cytocompatibility of the gelatin–collagen scaffolds. However, the scaffolds with 25% HA exhibited remarkable enhancement in physicochemical characteristics of the scaffolds including cell viability, growth, and attachment as well as their physical structure. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3130–3139, 2014.
Natural history and pregnancy outcome in patients with placental chorioangioma
Authors: Liu Haiyan , Gu Weirong , Li Xiaotian 
Published: October 2013

ABSTRACTPurposeTo evaluate the natural history and outcome of pregnancies in patients with placental chorioangioma.MethodsA total of 16 placentas with a histologic diagnosis of chorioangioma were identified, and the natural history and outcome of pregnancy were evaluated. This study was approved by the Institutional Ethics Committees of our unit, and written informed consent was obtained from all study participants.ResultsThirteen of the 16 cases were associated with a wide variety of fetal complications. Two‐thirds of the cases developed complications that either required elective delivery because of fetal distress (n = 4), fetal heart failure (n = 1), oligohydramnion (n = 1), and premature labor of dichorionic twins (n = 1) or resulted in intrauterine fetal death and termination of pregnancy (n = 2).ConclusionsPlacental chorioangioma was associated with the development of polyhydramnios, fetal growth restriction, and fetal distress in a significant number of cases. The size, vascularity, and location of the chorioangioma may be three independent factors of maternal and fetal complications. Any of these three factors can influence the outcome of pregnancy. Close antenatal examination should be routinely practiced to allow the timely diagnosis of early fetal heart failure. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:74–80, 2014
Renal carcinomas associated with Xp11.2 translocations/TFE3 gene fusions: Findings on MRI and computed tomography imaging
Authors: Liu Kefu , Xie Ping , Peng Weijun , Zhou Zhengrong 
Published: October 2013

PurposeTo retrospectively analyze MRI and computed tomographic (CT) findings from renal carcinomas associated with Xp11.2 translocations/TFE3 gene fusions (Xp11‐RCC).Materials and MethodsInstitutional review board permission was obtained to review patient medical records, and the requirement for informed consent was waved . The clinical and MRI/CT features of five cases with Xp11‐RCC that were confirmed by pathology were analyzed retrospectively. The image characteristics included the lesion location and size, contribution of cystic and solid components, intratumoral necrosis or hemorrhage, invasion of perinephric tissue and renal sinus, lymphadenopathy, major venous or arterial vascular invasion, pattern of the tumor growth, intratumor calcification and lipids, homogeneity of SI on T2‐weighted images, attenuation and SI of the mass with respect to the normal renal cortex on precontrast and contrasted CT/MRI images, tumor SIs, tumor attenuations and tumor‐to‐cortex indices, homogeneity of enhancement on the contrasted images.ResultsThe mean age was 32 years (range, 15–47 years). Most patients (4/5) were women. All tumors showed a cortical location. The average tumor size was 9 cm (range, 4–18 cm). Four tumors comprised a predominantly solid lesion with focal necrosis, and one tumor comprised a solid lesion with significant necrosis. All tumors showed intertumor hemorrhage, infiltrative growth and invasion of the perirenal adipose/renal sinus. Four cases showed retroperitoneal lymphadenopathy, of which one case showed simultaneous mediastinal and supraclavicular lymphadenopathy. All tumors from four cases showed mild hyperintensity on T1‐weighted MRI images, and three tumors showed hypointensity on T2‐weighted MRI images relative to the renal cortex except for 1 tumor that showed significant hemorrhage and a relative hyperintensity. For 3 cases who were imaged with CT, two tumors imaged using nonenhanced CT images showed mild hyperdensity relative to the renal cortex. Calcification was noted in all three tumors. All tumors showed mild, persistent enhancement.ConclusionTypical Xp11‐RCC manifests as an advanced, solid renal mass with mild persistent enhancement, a prevalence of intertumor hemorrhage/calcification, and a cortical epicenter location. The predilection for children and young adults is a useful clinical feature when confirming a diagnosis of Xp11‐RCC. J. Magn. Reson. Imaging 2014;40:440–447. © 2013 Wiley Periodicals, Inc.
The prevalence of neutralizing antibodies against adeno‐associated virus capsids is reduced in young Japanese individuals
Authors: Mimuro Jun , Mizukami Hiroaki , Shima Midori , Matsushita Tadashi , Taki Masashi , Muto Shinji , Higasa Satoshi , Sakai Michio , Ohmori Tsukasa , Madoiwa Seiji , Ozawa Keiya , Sakata Yoichi 
Published: October 2013

AbstractPre‐existing antibodies against adeno‐associated virus (AAV), caused by natural AAV infections, interfere with recombinant AAV vector‐mediated gene transfer. We studied the prevalence of neutralizing antibodies against AAV serotypes 1, 2, 5, 8, and 9 in healthy subjects (n = 85) and hemophilia patients (n = 59) in a Japanese population. For healthy subjects, the prevalence of neutralizing antibodies against AAV serotypes 1, 2, 5, 8, and 9 was 36.5%, 35.3%, 37.6%, 32.9%, and 36.5%, respectively, while that in hemophilia patients was 39.7%, 28.8%, 35.6%, 32.9%, and 27.4%, respectively. There was no difference in the prevalence of neutralizing antibody against each AAV serotype between the healthy subjects and the hemophilia patients. The prevalence of neutralizing antibodies against all AAV serotypes increased with age in both healthy subjects and hemophilia patients. High titers of neutralizing antibodies against AAV2 (≥1:224) and AAV8 (≥1:224) were more evident in older individuals (≥42 years old). Approximately 50% of all screened individuals were seronegative for neutralizing antibodies against each AAV tested, while approximately 25% of individuals were seropositive for each AAV serotype tested. The prevalence of seronegativity for all AAV serotypes was 67.0% (healthy subjects, 68.6%; hemophilia patients, 65.0%) and 18.6% (healthy subjects, 20.5%; hemophilia patients, 15.7%) in young (<42 years old) and older subjects (≥42 years old), respectively. The findings from this study suggested that young subjects are more likely to be eligible for gene therapy based on AAV vectors delivered via an intravascular route because of the low prevalence of antibodies to AAV capsids. J. Med. Virol. 86:1990–1997, 2014. © 2013 Wiley Periodicals, Inc.
One‐Pot Synthesis of PTFEMA‐b‐PMMA‐b‐PTFEMA by Controlled Radical Polymerization with a Difunctional Initiator in Conjugation with Photoredox Catalyst of Ir(ppy)3 Under Visible Light
Authors: Zhang Xianhong , Zhao Changwen , Ma Yuhong , Chen Haochuan , Yang Wantai 
Published: October 2013

Visible‐light‐induced free radical polymerization of methyl methacrylate (MMA) and 1,1,1‐trifluoroethyl methacrylate (TFEMA) with a difunctional initiator, dimethyl 2,6‐dibromoheptanedioate (DMDBHD), conjugated with a photoredox catalyst, tris(2‐phenylpyridinato)iridium(III) (fac‐[Ir(ppy)3]), is investigated. Kinetic studies demonstrate that homopolymerizations of both MMA and TFEMA are controlled radical polymerizations. The linear increase of molecular weights with monomer conversion and the narrow PDIs (1.2–1.4) reveal a good living character. In addition, PTFEMA‐b‐PMMA‐b‐PTFEMA triblock copolymer is prepared by a one‐pot process with sequential monomer addition. The of the triblock copolymers increases linearly with monomer conversion and the PDI of block copolymers is still maintained around 1.2–1.4. Experimental data confirm that the products are pure block polymers. Furthermore, the molar fraction of the TFEMA monomeric unit in the block copolymer is about 21.96%, close to the theoretical value 21.00% calculated from the monomer conversion.
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Synthesis of Diverse Asymmetric α,ω‐Dienes Via the Passerini Three‐Component Reaction for Head‐to‐Tail ADMET Polymerization
Authors: Sehlinger Ansgar , de Espinosa Lucas Montero , Meier Michael A. R. 
Published: October 2013

The Passerini three‐component reaction is applied to synthesize, in a one‐step procedure, diverse asymmetric α,ω‐dienes containing an acrylate and a terminal olefin. Such monomers are well known to undergo head‐to‐tail acyclic diene metathesis (ADMET) polymerization due to the high cross‐metathesis selectivity between acrylates and terminal olefins. Additionally, amphiphilic block copolymers are synthesized using a monofunctional PEG480 monoacrylate, which acts as a selective chain‐transfer agent during the polymerization process. Thus, control over the molecular weight of the amphiphilic ADMET polymers is shown by using different ratios of mono­mer and chain‐transfer agent. All the polymers are thoroughly characterized, and their ability to form nanoparticles in aqueous solution is studied.
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Radiofrequency pulse design in parallel transmission under strict temperature constraints
Authors: Boulant Nicolas , Massire Aurélien , Amadon Alexis , Vignaud Alexandre 
Published: October 2013

PurposeTo gain radiofrequency (RF) pulse performance by directly addressing the temperature constraints, as opposed to the specific absorption rate (SAR) constraints, in parallel transmission at ultra‐high field.MethodsThe magnitude least‐squares RF pulse design problem under hard SAR constraints was solved repeatedly by using the virtual observation points and an active‐set algorithm. The SAR constraints were updated at each iteration based on the result of a thermal simulation. The numerical study was performed for an SAR‐demanding and simplified time of flight sequence using B1 and ΔB0 maps obtained in vivo on a human brain at 7T.ResultsThe proposed adjustment of the SAR constraints combined with an active‐set algorithm provided higher flexibility in RF pulse design within a reasonable time. The modifications of those constraints acted directly upon the thermal response as desired.ConclusionAlthough further confidence in the thermal models is needed, this study shows that RF pulse design under strict temperature constraints is within reach, allowing better RF pulse performance and faster acquisitions at ultra‐high fields at the cost of higher sequence complexity. Magn Reson Med 72:679–688, 2014. © 2013 Wiley Periodicals, Inc.
Synthesis of water‐soluble allyl‐functionalized oligochitosan and its modification by thiol–ene addition in water
Authors: Illy Nicolas , Robitzer Mike , Auvergne Rémi , Caillol Sylvain , David Ghislain , Boutevin Bernard 
Published: October 2013

ABSTRACTA novel, straightforward and versatile chemical pathway has been studied to functionalize water‐soluble chitosan oligomers. This metal‐free methodology is based on the epoxy‐amine reaction of the allyl glycidyl ether with chitosan, followed by thiol‐ene radical coupling reaction of ω‐functional mercaptans, using 4,4′‐Azobis(4‐cyanovaleric acid) as a free radical initiator. Both reactions were entirely carried out in water. In a preliminary step, chitosan depolymerization was carried out using H2O2 in an acetic medium under 100 W microwave irradiation, optimizing the yield of water‐soluble oligomers. Functionalization by six different thiols bearing alcohol, carboxylic acid, ester, and amino groups was then performed, leading to a range of functional oligochitosans with different grafting efficiencies. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 39–48
Photovoltaic properties and femtosecond time‐resolved fluorescence study of polyoxometalate‐containing rod–coil diblock copolymers
Authors: Li Yong , Jin Lu , Chakraborty Sanjiban , Li Shaohua , Lu Peifen , Zhu Da‐Ming , Yan Xingzhong , Peng Zhonghua 
Published: October 2013

ABSTRACTThe photovoltaic properties and exciton decay dynamics of three polyoxometalate (POM)‐containing hybrid rod–coil diblock copolymers (HDCPs), PS‐Mo6‐PT1–3, are studied. Single‐component photovoltaic cells of PS‐Mo6‐PT2 and inverted solar cells based on ZnO nanorod arrays/PS‐Mo6‐PT1–3 are fabricated showing power conversion efficiencies only up to 0.055%. To understand the poor photovoltaic performance, femtosecond fluorescence up‐conversion technique is used to study the exciton decay dynamics of all three HDCPs. Drastically different fluorescence dynamics of the three HDCPs are observed in dilute solutions, which is attributed to the different extent and different type of interpolymer association depending on the P3HT rod block length and the cluster loading ratio. While both cation‐mediated POM cluster association and P3HT‐P3HT π‐stacking contribute significantly to PS‐Mo6‐PT2 aggregation, the aggregation of PS‐Mo6‐PT1 and that of PS‐Mo6‐PT3 is driven predominantly by cluster association and π‐stacking, respectively. In conjunction with the high residual polarization anisotropy, it is concluded that charge transfer from P3HT excitons to POM clusters in all three HDCPs is inefficient. An improved system with direct π‐conjugation between the POM clusters and the rod block addressing this issue has been proposed. © 2013 Wiley Periodicals, 2014, 52, 122–133
Impact of composition and fabrication method on the corrosion behavior of tungsten heavy alloys in aqueous solutions
Authors: Abdel Hamid Z. , Hassan H. B. 
Published: October 2013

Tungsten heavy alloys (WHAs) are kind of composite materials; these alloys provide a unique combination of properties such as high density, excellent mechanical properties and good corrosion resistance that making them increasingly attractive in many practical applications. In this work, the corrosion behavior of the investigated tungsten heavy alloys with the composition of (95% W–3.5% Ni–1.5% Fe), (93% W–4.5% Ni–1.0% Fe–1.5% Co) and (90% W–6% Ni–4% Cu) fabricated by either chemical or mechanical technique has been evaluated through potentiodynamic polarization measurements in different aqueous solutions of 0.6 M NaCl, 0.1 M HCl and 0.1 M NaOH. The extent of the corrosion has been illustrated by examining the surfaces of WHAs before and after the corrosion test using SEM. It includes general dissolution, localized attack of the binder phase and tungsten grain loss, where the extent of each of these depends on the fabrication technique and the alloy composition as well as the pH of the medium. Copyright © 2013 John Wiley & Sons, Ltd.
Research highlights

Tungsten heavy alloys are prepared by chemical and mechanical techniques.
They exhibited different corrosion rates in different media.
(93% W–4.5% Ni–1.0% Fe–1.5% Co) alloy shows the lowest corrosion rate.
Shaping partnerships by doing the work
Authors: Korum Kathy 
Published: October 2013

AbstractPartnership as an ordinary, everyday way of doing business within Saint Paul Parks and Recreation (P&R) has often been limited to working with individuals, groups, or agencies through a contract, generally to provide fee‐based programs or services. This approach does not encourage new ways of thinking about or working with other organizations on a common purpose or service. Other partnership approaches are necessary to bring innovation to this work. These must allow and foster space for joint negotiation, for ways to meet needs and wants of both organizations and their missions, and focus on meeting community needs.