bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photodynamic antimicrobial effect of safranine O on an ex vivo periodontal biofilm
Authors: Voos Amelia C. , Kranz Stefan , Tonndorf‐Martini Silke , Voelpel Andrea , Sigusch Holger , Staudte Henrike , Albrecht Volker , Sigusch Bernd W. 
Published: January 2014

AbstractBackground and ObjectiveThe increasing resistance of oral pathogens against antibiotic measures urgently requires new therapeutic strategies. In this context, antimicrobial photodynamic therapy (aPDT) may play a crucial part in the future. The aim of the present study was to compare the antibacterial efficiency of aPDT using the photosensitizer safranine O with that of chlorhexidine (0.2% CHX) on an ex vivo biofilm.MethodsFirst the antibacterial activity of both measures against planktonic cultures of Streptococcus gordonii ATCC 33399, Streptococcus mutans ATCC 25175, Fusobacterium nucleatum ATCC 10953, Aggregatibacter actinomycetemcomitans ATCC 33384 and Porphyromonas gingivalis ATCC 33277 was observed. Then a patient specific ex vivo biofilm was established from plaque and saliva samples of patients (n = 19) with chronic periodontitis. The antibacterial effects of aPDT and of 0.2% CHX were determined on the ex vivo biofilms cultivated for 24 and 72 hours. After cultivation of the treated samples on blood agar (2 days) the results were quantified by counting the colony forming units (cfu/ml).ResultsPhotodynamic treatment with safranine O showed a distinct antibacterial effect on F. nucleatum and P. gingivalis. Whereas S. gordonii was suppressed completely by aPDT, treatment with 0.2% CHX caused only a partial reduction. In the ex vivo biofilm model (24‐hour biofilm), aPDT caused a significantly higher bacterial killing than treatment with 0.2% CHX. Compared to the untreated control, there was no significant difference on the 72‐hour biofilm for both methods.ConclusionsThe results show that oral‐pathogenic species in planktonic solution can be suppressed significantly by aPDT with safranine O. Especially for bacteria in a 24‐hour ex vivo biofilm, this method is more effective than treatment with 0.2% CHX. Both antibacterial treatments did not show any significant effect on the biofilm cultivated for 72 hours. Lasers Surg. Med. 46:235–243, 2014. © 2014 Wiley Periodicals, Inc.
Attenuation of acne scars using high power fractional ablative unipolar radiofrequency and ultrasound for transepidermal delivery of bioactive compounds through microchannels
Authors: Trelles Mario A. , Martínez‐Carpio Pedro A. 
Published: January 2014

Background and ObjectiveTo determine the efficacy and safety of a new method for treating acne scarring over a short‐term period of 2 months and a long‐term period of 6 months.Materials and MethodsSix faces and 13 shoulders or backs for a total of 19 patients were treated, all of which displayed varying degrees of acne scarring, from moderate to severe. A newly developed high‐power unipolar fractional ablative radiofrequency technology was used (iPixel™ RF, Alma Lasers, Caesarea, Israel), with acoustic pressure ultrasound guided dermal injection of the PixelTreat Scars preparation (Alma Lasers), through RF Pixel fractionated microchannels. All patients underwent four treatment sessions at 3‐week intervals.ResultsSignificant improvement was observed in scarring, both on the face (P < 0.0001), and on the back and shoulders (P < 0.0001). After 2 months, the percentage of fading on total scarring was 57% on the face and 49% on the back and shoulders; after 6 months, the percentage increased to 62% on the face, and 58% on the back and shoulders, respectively. Patients reported to be Somewhat Satisfied (16%), Satisfied (53%), and Very Satisfied (31%). No unexpected side effects to the ablation and no hypersensitive reactions to PixelTreat Scars were observed.ConclusionThe bimodal procedure is safe and effective in reducing acne scarring. This represents a new therapeutic alternative of great interest, to be used either as a monotherapy, or in combination with other treatments. Lasers Surg. Med. 46:152–159, 2014. © 2014 Wiley Periodicals, Inc.
Designing Injectable, Covalently Cross‐Linked Hydrogels for Biomedical Applications
Authors: Patenaude Mathew , Smeets Niels M. B. , Hoare Todd 
Published: January 2014

Hydrogels that can form spontaneously via covalent bond formation upon injection in vivo have recently attracted significant attention for their potential to address a variety of biomedical challenges. This review discusses the design rules for the effective engineering of such materials, and the major chemistries used to form injectable, in situ gelling hydrogels in the context of these design guidelines are outlined (with examples). Directions for future research in the area are addressed, noting the outstanding challenges associated with the use of this class of hydrogels in vivo.image
Approximate Fourier domain expression for Bloch–Siegert shift
Authors: Turk Esra Abaci , Ider Yusuf Ziya , Ergun Arif Sanli , Atalar Ergin 
Published: January 2014

PurposeIn this study, a new simple Fourier domain‐based analytical expression for the Bloch–Siegert (BS) shift‐based B1 mapping method is proposed to obtain
more accurately while using short BS pulse durations and small off‐resonance frequencies.Theory and MethodsA new simple analytical expression for the BS shift is derived by simplifying the Bloch equations. In this expression, the phase is calculated in terms of the Fourier transform of the radiofrequency pulse envelope, and thus making the off‐ and on‐resonance effects more easily understandable. To verify the accuracy of the proposed expression, Bloch simulations and MR experiments are performed for the hard, Fermi, and Shinner–Le Roux pulse shapes.ResultsAnalyses of the BS phase shift‐based B1 mapping method in terms of radiofrequency pulse shape, pulse duration, and off‐resonance frequency show that
can be obtained more accurately with the aid of this new expression.ConclusionsIn this study, a new simple frequency domain analytical expression is proposed for the BS shift. Using this expression,
values can be predicted from the phase data using the frequency spectrum of the radiofrequency pulse. This method works well even for short pulse durations and small offset frequencies. Magn Reson Med 73:117–125, 2015. © 2014 Wiley Periodicals, Inc.
The effect of low b‐values on the intravoxel incoherent motion derived pseudodiffusion parameter in liver
Authors: Cohen Alexander D. , Schieke Moira C. , Hohenwalter Mark D. , Schmainda Kathleen M. 
Published: January 2014

PurposeTo examine the effect of low b‐values (0 < b < 50 s/mm2) on the calculation of the intravoxel incoherent motion (IVIM) derived pseudodiffusion parameter in the normal liver.MethodsSimulations were performed to examine the effects of adding low b‐values on the pseudodiffusion parameter. Low b‐values were cumulatively added to the distribution and the IVIM signal was generated with varying pseudodiffusion values. The signal was fit with the IVIM model after the addition of Gaussian noise, and the simulated values were compared with the true values. In addition, the livers of eight control subjects were imaged using respiratory‐triggered DWI. Pseudodiffusion was calculated with and without low b‐values and compared.ResultsPseudodiffusion tended to be underestimated when low b‐values were not included in the b‐value distribution as predicted by simulations and confirmed with in vivo imaging. The number of outlier values was also reduced as more low b‐values were added.ConclusionIn conclusion, this study showed pseudodiffusion in the liver tended to be underestimated when too few low b‐values (0 < b < 50 s/mm2) were included in the distribution. Therefore, it is recommended to include at least two low b‐values when performing liver IVIM studies. Magn Reson Med 73:306–311, 2015. © 2014 Wiley Periodicals, Inc.
Dynamically phase‐cycled radial balanced SSFP imaging for efficient banding removal
Authors: Benkert Thomas , Ehses Philipp , Blaimer Martin , Jakob Peter M. , Breuer Felix A. 
Published: January 2014

PurposeBalanced steady‐state free precession (bSSFP) imaging suffers from banding artifacts due to its inherent sensitivity to inhomogeneities in the main magnetic field. These artifacts can be removed by the acquisition of multiple images at different frequency offsets. However, conventional phase‐cycling is hindered by a long scan time. The purpose of this work is to present a novel approach for efficient banding removal in bSSFP imaging.Theory and MethodsTo this end, the phase‐cycle during a single‐shot radial acquisition of an image was dynamically changed. Thus, each projection is acquired with a different frequency offset. Using conventional radial gridding, an artifact‐free image can be reconstructed out of this dataset.ResultsThe approach is validated at clinical field strength [3.0 Tesla (T)] as well as at ultrahigh field (9.4T). Robust elimination of banding artifacts was obtained for different imaging regions, including brain imaging at ultrahigh field with an in‐plane resolution of 0.25 × 0.25 mm2. Besides banding artifact‐free imaging, the applicability of the proposed technique for fat‐water separation is demonstrated.ConclusionDynamically phase‐cycled radial bSSFP has the potential for banding‐free bSSFP imaging in a short scan time, in the presence of severe field inhomogeneities and at high resolution. Magn Reson Med 73:182–194, 2015. © 2014 Wiley Periodicals, Inc.
Combining perfluorocarbon and superparamagnetic iron‐oxide cell labeling for improved and expanded applications of cellular MRI
Authors: Hitchens T. Kevin , Liu Li , Foley Lesley M. , Simplaceanu Virgil , Ahrens Eric T. , Ho Chien 
Published: January 2014

PurposeThe ability to detect the migration of cells in living organisms is fundamental in understanding biological processes and important for the development of novel cell‐based therapies to treat disease. MRI can be used to detect the migration of cells labeled with superparamagnetic iron‐oxide (SPIO) or perfluorocarbon (PFC) agents. In this study, we explored combining these two cell‐labeling approaches to overcome current limitations and enable new applications for cellular MRI.MethodsWe characterized 19F‐NMR relaxation properties of PFC‐labeled cells in the presence of SPIO and imaged cells both ex vivo and in vivo in a rodent inflammation model to demonstrate selective visualization of cell populations.ResultsWe show that with UTE3D, RARE, and FLASH 19F images one can uniquely identify PFC‐labeled cells, colocalized PFC‐ and SPIO‐labeled cells, and PFC/SPIO‐colabeled cells.ConclusionThis new methodology has the ability to improve and expand applications of MRI cell tracking. Combining PFC and SPIO strategies can potentially provide a method to quench PFC signal transferred from dead cells to macrophages, thereby eliminating false positives. In addition, combining these techniques could also be used to track two cell types simultaneously and probe cell–cell proximity in vivo with MRI. Magn Reson Med 73:367–375, 2015. © 2014 Wiley Periodicals, Inc.
Microchemical inhomogeneity in eutectic Pb–Bi alloy quenched from melt
Authors: Mezzi A. , Kaciulis S. , Balijepalli S. K. , Montanari R. , Varone A. , Amati M. , Aleman B. 
Published: January 2014

ABSTRACTThe liquid lead‐bismuth eutectic alloy is of great interest for applications in advanced nuclear systems; in particular, it is considered to be a good candidate as a coolant and neutron spallation source material for MYRRHA (http://myrrha.sckcen.be/), an accelerator driven system. Investigations based on mechanical spectroscopy experiments and high‐temperature X‐ray diffraction evidenced that the structure of the liquid alloy is not stable but undergoes relevant changes as the temperature increases. To understand whether such transformations, occurring in the liquid state involve elemental clustering, the alloy has been water‐quenched from the liquid state at three different temperatures. After quenching, the samples have been investigated by standard XPS and scanning photoemission microscopy at the ELETTRA synchrotron. The SPEM results showed that the distribution of two metals is characterised by the following: (i) Pb‐enriched clusters, (ii) Bi‐enriched clusters and (iii) matrix in near eutectic composition. The statistics of clusters size was evaluated from the linescans of chemical Pb/Bi images. The average size of clusters is noticeably reduced by increasing quenching temperature: it is in the range of 1 ÷ 3 µm at 313 °C and passes to 0.5 ÷ 0.9 µm at 518 °C. Therefore, scanning photoemission microscopy results evidenced a structural and microchemical rearrangement of the atoms in the melt consisting in the evolution of cluster size and composition. Copyright © 2014 John Wiley & Sons, Ltd.
Predictive value of ophthalmic artery Doppler velocimetry in relation to development of pre‐eclampsia
Authors: Matias D. S. , Costa R. F. , Matias B. S. , Gordiano L. , Correia L. C. L. 
Published: January 2014

ABSTRACTObjectiveTo test the hypothesis that ophthalmic artery Doppler velocimetry is predictive of the development of pre‐eclampsia (PE).MethodsThis was a prospective cohort study that included pregnant women in the second trimester who had risk factors for PE. Seven ophthalmic artery Doppler parameters, in addition to uterine artery (UtA) Doppler and clinical variables, were investigated for their prognostic value with respect to PE.ResultsA total of 347 women were recruited, of whom 40 developed PE. A comparison of the mean ophthalmic artery Doppler parameter values between women with and those without PE showed statistically significant differences in several parameters: peak systolic velocity, end‐diastolic velocity, mean velocity, peak mesodiastolic velocity (PMDV) and peak ratio. After adjusting for confounding variables, only PMDV remained statistically significant (P < 0.001), with an area under the receiver–operating characteristics curve (AUC) of 0.73. The best cut‐off for predicting PE was a PMDV of > 22.11 cm/s, with sensitivity of 70%, specificity of 75%, positive likelihood ratio of 2.8, negative likelihood ratio of 0.4, positive predictive value of 28% and negative predictive value of 95%. The AUC increased from 0.72 to 0.78 when the PMDV was incorporated into a prediction model based on clinical variables, demonstrating that this marker increased the discriminatory capability of the model. The performance of ophthalmic artery Doppler was similar to that of UtA Doppler for predicting PE. Additionally, the AUC increased significantly from 0.82 to 0.88 when the PMDV was incorporated into the model containing clinical variables and UtA Doppler indices.ConclusionA high ophthalmic artery PMDV in the second trimester of pregnancy is an independent predictor of PE that increases the discriminatory ability of clinical markers, as well as of models that include clinical variables and UtA Doppler indices. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.
Incorporation and application of resilience in the context of water‐sensitive urban design: linking European and Australian perspectives
Authors: Salinas Rodriguez Carlos N. A. , Ashley Richard , Gersonius Berry , Rijke Jeroen , Pathirana Assela , Zevenbergen Chris 
Published: January 2014

The water sensitive city is a term within urban water management in which the concept of resilience to extreme climatic events and climate change plays a key role and represents the interaction between different branches of water science, engineering, and other domains such as urban planning and design. In this context, resilience is the ability of a system to cope with or recover from inter alia floods and droughts and also to retain original identity in some form in the face of long‐term change. It is generally accepted that sustainable systems with respect to water management are mainly dominated by their resilience, which is intrinsic to water sensitive cities, and includes social, economic, and environmental as well as technical systems, such as built infrastructure and environments, and their interactions. Therefore, each system cannot be considered in isolation but needs to be seen as a part of wider aspects of water and urban services and utilities in resilient cities. New urban development can be better provided with flood and drought resilience because of the opportunity for the implementation of the available technical, social, and economic knowledge. This is different in the case of existing urban areas where maximization of the value and use of water requires more and in‐depth analysis. The growing movement for water‐sensitive urban design (WSUD), a concept developed in Australia, provides inspiration for maximizing the value and use of water in urban areas, with an increasing consideration of flood and drought resilience. Synergistic integration between the extant knowledge on WSUD together with resilience approaches can lead to the establishment of a new model for water sensitive cities which are also flood resilient. Similarly, dealing with urban flooding in a wise manner can simultaneously optimize the use of all kinds of available resources—also enhancing resilience for droughts.This article is categorized under:

Engineering Water > Planning Water
The Phosphides U6Fe30P19 and U6Co30P19 with the ­Yb6Co30P19 Structure Type
Authors: Tarasenko Mariya S. , Albering Jörg H. , Jeitschko Wolfgang , Ibers James A. 
Published: January 2014

AbstractPowders of U6Fe30P19 and U6Co30P19 were synthesized through the use of tin fluxes. Examination of these powders at 298 K by the Guinier technique led to lattice parameters in the hexagonal system for U6Fe30P19 of a = 14.762(2) Å, c = 3.6315(4) Å, c/a = 0.2460, V = 685.3 Å3 and for U6Co30P19 of a = 14.722(3) Å, c = 3.6355(6) Å, c/a = 0.2469, V = 682.4 Å3. Single crystals of U6Fe30P19 were synthesized and its structure was determined. U6Fe30P19 crystallizes in the space group C1,3h – P$\bar{6}$ of the hexagonal system in the Yb6Co30P19 structure type with one formula unit in a cell of dimensions determined at 100 K of a = 14.7206(4) Å, c = 3.6243(1) Å, c/a = 0.2462, V = 680.15(4) Å3. The asymmetric unit of U6Fe30P19 comprises two U, ten Fe, and seven different P atoms. Each U atom is situated in a trigonal prism of six P atoms; each Fe atom is coordinated either by a tetrahedron or a square pyramid of P atoms. The distances are all less than 2.9 Å. In addition, the structure contains numerous Fe–Fe bonds covering the range from 2.55 to 2.71 Å. The proper space group of the Yb6Co30P19 structure type is discussed.
Synthesis of 1, 6‐Bis(trimethylsilylamino)benzene‐Substituted Aluminum Hydrides: The Characterization of a Product from Ring‐Opening Reaction of Tetrahydrofuran
Authors: Yang Zhi , Hao Pengfei , Ma Xiaoli , Roesky Herbert W. , Yang Ying , Li Jiarong 
Published: January 2014

AbstractThe reaction of 1, 6‐bis(trimethylsilylamino)benzene (LH2) (1) in toluene with H3Al·NMe3 yielded the aluminum monohydride with coordinate NMe3 of composition [1, 6‐(Me3SiN)2C6H4]AlH(NMe3) (2). However, the same reaction in THF resulted in the ring opening of THF with formation of {[1, 6‐(Me3SiN)2C6H4]AlH}2O(CH2)4NMe3 (3) in good yield. Both the spectroscopic data in solution as well as the X‐ray crystallographic data confirmed that a THF molecule underwent a ring‐opening reaction. Compound 2 is the first monomeric aluminum hydride compound containing the 1, 6‐bis(trimethylsilylamino)benzene. Compound 3 exhibits an intermolecular zwitterion of composition –O(CH2)4NMe3+ between two aluminum atoms. Complexes 2 and 3 were characterized by 1H NMR spectroscopy, elementary analysis, and single‐crystal X‐ray diffraction studies.
Comparison of microbial communities involved in souring and corrosion in offshore and onshore oil production facilities in Nigeria
Authors: Okoro Chuma , Smith Seun , Chiejina Leo , Lumactud Rhea , An Dongshan , Park Hyung Soo , Voordouw Johanna , Lomans Bart P , Voordouw Gerrit 
Published: January 2014

Abstract
Samples were obtained from the Obigbo field, located onshore in the Niger delta, Nigeria, from which oil is produced by injection of low-sulfate groundwater, as well as from the offshore Bonga field from which oil is produced by injection of high-sulfate (2,200 ppm) seawater, amended with 45 ppm of calcium nitrate to limit reservoir souring. Despite low concentrations of sulfate (0–7 ppm) and nitrate (0 ppm), sulfate-reducing bacteria (SRB) and heterotrophic nitrate-reducing bacteria (NRB) were present in samples from the Obigbo field. Biologically active deposits (BADs), scraped from corrosion-failed sections of a water- and of an oil-transporting pipeline (both Obigbo), had high counts of SRB and high sulfate and ferrous iron concentrations. Analysis of microbial community composition by pyrosequencing indicated anaerobic, methanogenic hydrocarbon degradation to be a dominant process in all samples from the Obigbo field, including the BADs. Samples from the Bonga field also had significant activity of SRB, as well as of heterotrophic and of sulfide-oxidizing NRB. Microbial community analysis indicated high proportions of potentially thermophilic NRB and near-absence of microbes active in methanogenic hydrocarbon degradation. Anaerobic incubation of Bonga samples with steel coupons gave moderate general corrosion rates of 0.045–0.049 mm/year, whereas near-zero general corrosion rates (0.001–0.002 mm/year) were observed with Obigbo water samples. Hence, methanogens may contribute to corrosion at Obigbo, but the low general corrosion rates cannot explain the reasons for pipeline failures in the Niger delta. A focus of future work should be on understanding the role of BADs in enhancing under-deposit pitting corrosion.
Four Amino Acid Residues Influence the Substrate Chain‐Length and Regioselectivity of Siganus canaliculatus Δ4 and Δ5/6 Desaturases
Authors: Lim Ze Long , Senger Toralf , Vrinten Patricia 
Published: January 2014

AbstractAlthough ω3‐ and ω6‐ desaturases have been well studied in terms of substrate preference and regiospecificity, relatively little is known about the membrane‐bound, “front‐end” long chain fatty acid desaturases, such as ∆4, Δ5 or Δ6 desaturases. The first vertebrate ∆4 desaturase was recently identified in the marine teleost fish Siganus canaliculatus (S. canaliculatus), which also possesses a bifunctional Δ5/6 desaturase. These two long chain polyunsaturated fatty acid desaturases are very different in terms of regiospecificity and substrate chain‐length, but share an unusually high degree of amino acid identity (83 %). We took advantage of this similarity by constructing a series of chimeric enzymes, replacing regions of one enzyme with the corresponding sequence of the other. Heterologous expression of the chimeric series of enzymes in yeast indicated that the substitution of a four amino acid region was sufficient to convert a ∆4 desaturase to an enzyme with ∆6 desaturase activity, and convert a ∆5/6 desaturase to an enzyme with a low level of ∆4 desaturase activity. In addition, enzymes having both ∆4 and ∆6 desaturase activities were produced by single or double amino acid substitutions within this four‐amino acid region.
Occurrence of PGE Mineralisation in Bangur, Kendujhar District, Odisha
Authors: Sahoo K. C. , Mohanty M. , Sahoo P. , Rath S. C. , Ray S. B. 
Published: January 2014

Abstract:
PGE mineralisation of significant grade and extent is reported from Bangur chromite mining area, Kendujhar district, Odisha, located to the south of the well known Baula-Nuasahi ultramafic complex. The hitherto unknown PGE mineralisation is established in a ferritchromit rich breccia zone occurring within Bangur litho-mélange. The mineralized breccia zone is traced for about 550m with a mean width of 12m in NW-SE direction. Chemical analysis of drill core samples by ICP-MS indicates an average ΣPGE content of 3.2 ppm dominated by Pt and Rh. Occurrence of discrete grains of PGM in sizes up to 45 microns is confirmed by SEM-EDX and EPMA study. Delineation of this PGE bearing zone stresses the need for preservation of gangue/matrix of the breccia zone, along with ferritchromit clasts, in the ongoing selective mining of chromite in Bangur.