bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zirconia phase transformation in retrieved, wear simulated, and artificially aged ceramic femoral heads
Authors: Parkes Maria , Sayer Kathryn , Goldhofer Markus , Cann Philippa , Walter William L. , Jeffers Jonathan 
Published: May 2017

ABSTRACTZirconia in Zirconia toughened alumina ceramic hip replacements exists in an unstable state and can transform in response to stress giving the material improved fracture toughness. Phase transformation also occurs under hydrothermal conditions such as exist in vivo. To predict the hydrothermal aging that will occur in vivo accelerated aging procedures have been used, but validation of these models requires the study of retrieved hip joints. Here 26 retrievals are analysed to determine the degree of phase transformation in vivo. These were compared with virgin heads, heads that had undergone the accelerated aging process and heads wear tested to 5 million cycles in a hip simulator. Monoclinic content and surface roughness were measured using Raman spectroscopy and white light interferometry respectively. The monoclinic content for retrieved heads was 28.5% ± 7.8, greater than twice that in virgin, aged, or wear tested heads and did not have a significant correlation with time, contrary to the predictions of the hydrothermal aging model. The surface roughness for retrieved heads in the unworn area was not significantly different to that in virgin, aged, or unworn areas of wear tested heads. However in worn areas of the retrieved heads, the surface roughness was higher than observed in wear simulator testing. These results indicate that current testing methodologies do not fully capture the operational conditions of the material and the real performance of future new materials may not be adequately predicted by current pre‐clinical testing methods. © 2017 The Authors.Journal of Orthopaedic ResearchPublished by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society 35:2781–2789, 2017.
Long‐chain ionic liquid based mixed hemimicelles and magnetic dispersed solid‐phase extraction for the extraction of fluorescent whitening agents in paper materials
Authors: Wang Qing , Qiu Bin , Chen Xianbo , Wang Bin , Zhang Hui , Zhang Xiaoyuan 
Published: May 2017

A novel mixed hemimicelles and magnetic dispersive solid‐phase extraction method based on long‐chain ionic liquids for the extraction of five fluorescent whitening agents was established. The factors influenced on extraction efficiency were investigated. Under the optimal conditions, namely, the pH of sample solution at 8.0, the concentration of long chain ionic liquid at 0.5 mmol/L, the amount of Fe3O4 nanoparticle at 12 mg, extraction time at 10 min, pH 6.0 of methanol as eluent, and the desorption time at 1 min, satisfactory results were obtained. Wide linear ranges (0.02–10 ng/mL) and good linearity were attained (0.9997–0.9999). The intraday and interday RSDs were 2.1–8.3%. Limits of detection were 0.004–0.01 ng/mL, which were decreased by almost an order of magnitude compared to direct detection without extraction. The present method was applied to extract the fluorescent whitening agents in two kinds of paper samples, obtaining satisfactory results. All showed results illustrated that the detection sensitivity was improved and the proposed method was a good choice for the enriching and monitoring of trace fluorescent whitening agents.
Nitrogen transport, transformation, and retention in the Three Gorges Reservoir: A mass balance approach
Authors: Ran Xiangbin , Bouwman Lex , Yu Zhigang , Beusen Arthur , Chen Hongtao , Yao Qingzhen 
Published: May 2017

AbstractDam construction in river systems affects the biogeochemistry of nitrogen (N), yet most studies on N cycling in reservoirs do not consider the transformations and retention of the different N species. This study addresses the N inputs, transport, transformations, and retention in the Three Gorges Reservoir (TGR) in the Changjiang River, the world largest water storage project, during its filling phase in 2004–2007. The results indicate that dissolved inorganic nitrogen (DIN) was the most abundant N form in the TGR and particulate N was only 2% to the total N flow and retention. About 34% of the dissolved organic nitrogen (DON), 64% of nitrite, and 44% of ammonia were retained by transformation within the TGR in 2007. Time‐series data show that about 8% of inflowing total dissolved N was lost by denitrification and sedimentation. Transformations of DON, nitrite and ammonia caused an increase of the nitrate load by 6%; and at the same time the DIN flux increased by 4% while the water moved through the TGR, which is the balance between formation and retention of DIN. The large contribution of biogeochemical transformations to nitrate loading in the TGR indicates the importance of internal processing for the river N species composition.
A Smart Nano‐Prodrug Platform with Reactive Drug Loading, Superb Stability, and Fast Responsive Drug Release for Targeted Cancer Therapy
Authors: Meng Hao , Zou Yan , Zhong Ping , Meng Fenghua , Zhang Jian , Cheng Ru , Zhong Zhiyuan 
Published: May 2017

AbstractNano‐prodrugs usually involve a multistep synthesis which largely compromises their benefits. Here, a smart nano‐prodrug platform with reactive drug loading, superb stability, and triggered drug release is reported for targeted melanoma therapy. cRGD‐decorated polymersomal mertansine prodrug (cRGD‐PS‐DM1) is readily fabricated from cRGD‐functionalized poly(ethylene glycol)‐b‐poly(trimethylene carbonate‐co‐dithiolane trimethylene carbonate) with simultaneous loading of mertansine (DM1) via thiol–disulfide exchange reaction and disulfide cross‐linking of polymersomal membrane. cRGD‐PS‐DM1 exhibits a size of ≈100 nm, little drug leakage, and fast DM1 release in the presence of 2 × 10−3–10 × 10−3
m glutathione. Tetrazolium‐based colorimetric assay (MTT) and confocal microscopy studies confirm effective homing of cRGD‐PS‐DM1 to αvβ3 overexpressing B16F10 melanoma cells. Notably, the in vivo studies show that cRGD‐PS‐DM1 has a greatly improved toleration as compared with free DM1 and effectively inhibits tumor growth and extends the survival time of B16F10 melanoma‐bearing mice. cRGD‐PS‐DM1 nano‐prodrug with reactive drug loading and multifunction provides an advanced nanomedicine for cancer therapy.
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Pluronic‐Induced Surface Etching of Biodegradable Nanofibers for Enhanced Adsorption of Serum Protein
Authors: Mao Wei , Yoo Hyuk Sang 
Published: May 2017

Manipulated roughness has been etched on nanofibers to modulate adsorption of serum proteins for serum‐free cells cultivation. Mixtures of Polycaprolactone and Pluronic with various blending ratios are electrospun to nanofibers and Pluronic is subsequently leached out by methanol. Electron microscopy reveals that surface roughness of the nanofibers is changed according to the contents of Pluronic. Both weight loss monitoring and NMR spectroscopy confirm that all Pluronic is leached out after methanol treatment. Water swelling ratio and protein adsorption of rougher nanofibers are higher than those of smoother ones. Also, when serum incorporation on the nanofibers is estimated in 0.01–10% serum solution, rougher nanofibers show higher serum incorporation and those soaked in 10% serum solution are employed for serum‐free cell cultivation. Viability of the cells cultivated on rougher nanofibers is much higher after 24 h. Thus, Pluronic‐induced leaching‐out strategy can be potentially employed for fabricating roughness on nanofibers for enhancing protein adsorption for serum‐free cell cultivation.
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Unusual Rheological Properties of Lightly Crosslinked Polydimethylsiloxane
Authors: Villani Vincenzo , Lavallata Vito 
Published: May 2017

The rheological behavior of elastomers of polydimethylsiloxane vinyl‐terminated has been investigated in both rotational and oscillating modes. Partially crosslinked liquid rubbers have been prepared, varying the curing agent‐to‐elastomer weight ratio p. Viscoelastic fluids with unusual rheological properties have been obtained. For small p, zero‐shear viscosity and storage dynamic modulus G′(ω) at low frequencies are obtained, lower than those of reference liquid elastomers. Outcomes are discussed according to the polymer tube model theory and an extension at nanoscale of the Einstein equation of viscosity proposed. The unentangled crosslinked nanodomain model has been proposed. At light networking, isolated crosslinked nanodomains would form and the longer chains will be preferentially bonded. This will determine a decrease in the entanglement density in the matrix. On the nanodomain surface the dangling chains will not be long enough to give stable entanglements, determining the formation of a free volume at the interface polymer matrix‐nanoparticles.
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Thiol‐Functionalized Organic Porous Polymers as a Support for Gold Nanoparticles and Its Catalytic Applications
Authors: Zhong Aiqing , Xu Yang , He Zidong , Zhang Hui , Wang Tianqi , Zhou Minghong , Xiong Linfeng , Huang Kun 
Published: May 2017

In this work, a novel synthesis approach of gold nanohybrid materials (Au/SH‐OPPs) is demonstrated using the thiol‐functionalized organic porous polymers (SH‐OPPs) as a support by a combination of hyper‐cross‐linking and molecular templating of functionalized bottlebrush copolymers. HAuCl4 as the gold source is in situ reduced to produce Au nanoparticles based on the strong action of gold with the thiol groups. The monodispersed Au nanoparticles are anchored on the SH‐OPPs with the small average particle size (3.0 ± 1.0 nm) and the high loading about 18%. Moreover, the resultant Au/SH‐OPPs exhibit excellent catalytic performance for the selective oxidation of benzyl alcohol.
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Solid State Polymerization of Poly(Ethylene Furanoate) and Its Nanocomposites with SiO2and TiO2
Authors: Achilias Dimitris S. , Chondroyiannis Antonis , Nerantzaki Maria , Adam Kyriakos‐Vasilios , Terzopoulou Zoe , Papageorgiou George Z. , Bikiaris Dimitrios N. 
Published: May 2017

In the present study, poly(ethylene furanoate) (PEF) and its nanocomposites with SiO2and TiO2have been prepared and studied. Emphasis is given to study the effect of different nanoadditives, time, and temperature on solid state polymerization (SSP) of PEF. SSP is conducted at 180, 190, and 200 °C for 1, 2, 3.5, and 5 h under vacuum application. From intrinsic viscosity ([η]) measurements it is found that in all SSP samples the molecular weight increase is time and temperature dependent. The addition of nanofillers results in polymer production with slightly higher average molecular weight, especially at lower temperatures. A simple kinetic model is also developed and used to predict the time evolution of polymer's [η], as well as the carboxyl and hydroxyl content during the SSP. From the experimental measurements and the theoretical simulation it is proved that the presence of the nanoadditives results in higher transesterification kinetic rate constants. Moreover, compared to poly(ethylene terephthalate) (PET), the lower [η] of PEF, results in a much higher number of hydroxyl end groups and larger tranesterification and esterification reaction rates. Finally, the activation energy for the transesterification of PEF is found to be much higher compared to that of PET.image
Fabrication of Large Area Broadband and Omnidirectional Antireflective Transparent Foils by Roll‐to‐Roll Extrusion Coating
Authors: Murthy Swathi , Lotz Mikkel Rønne , Feidenhans'l Nikolaj , Madsen Morten H. , Pedersen Henrik C. , Pranov Henrik , Taboryski Rafael 
Published: May 2017

This study investigates the fabrication and performance of broadband and omnidirectional antireflective polymer foils, in the visible spectrum (400–800 nm), consisting of subwavelength inverted moth‐eye structures. The foils are fabricated by a high throughput roll‐to‐roll extrusion coating process allowing structuring on both sides at a rate of 60 m min−1, with web width 45 cm. The highest average transmittance obtained in the visible spectrum is (98 ± 1) %; compared with (92 ± 1) % for the unstructured foil. The antireflective foil shows no significant difference in transmittance between normal incidence and incidence up to at least 60°. The foil performance is also investigated for different depths (Dp) and shapes of structures. The transmittance initially increases with Dp and reaches a maximum at Dp ≈ 120 nm. For process parameters yielding greater depths, other shape factors also play a critical role in the foil's antireflective properties.
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Internal Structure of Amorphous Electrospun Nanofiber: Oriented Molecular Chains
Authors: Xu Yiyang , Gao Yanhong , Wang Xiaofeng , Jiang Jing , Hou Jianhua , Li Qian 
Published: May 2017

The properties of polymeric nanofibers are determined by their internal structure. Although electrospun nanofibers have been widely applied in many fields, their internal structure is still not extensively reported, especially for amorphous nanofibers, which cannot be analyzed by studying the morphology of the crystal lamellar such as the crystalline nanofibers. In this study, the internal structure of electrospun amorphous polycarbonate (PC) nanofibers is investigated. The phase contrast and transmission electron microscopy images show that PC nanofibers exhibit a cylinder‐like structure composed of molecular chains that are highly oriented along the fiber axis. This interesting cylinder‐like internal structure may be the result of evaporation‐induced phase separation in the polymer solution jet and the high strain rate in the electrospinning process. The variation of mechanical properties of PC nanofibers agrees well with the varied internal structure of the nanofibers with different fiber diameters. Due to the high degree of molecular orientation, as‐spun PC nanofibers exhibit superior elastic modulus (6.2 GPa) and strength (780 MPa). The cylinder‐like structure provides an insight into the internal structure of an amorphous electrospun nanofiber, which helps optimize the mechanical performance of amorphous nanofibers and fiber‐based devices.
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Imaging features from pretreatment CT scans are associated with clinical outcomes in nonsmall‐cell lung cancer patients treated with stereotactic body radiotherapy
Authors: Li Qian , Kim Jongphil , Balagurunathan Yoganand , Liu Ying , Latifi Kujtim , Stringfield Olya , Garcia Alberto , Moros Eduardo G. , Dilling Thomas J. , Schabath Matthew B. , Ye Zhaoxiang , Gillies Robert J. 
Published: May 2017

PurposeTo investigate whether imaging features from pretreatment planning CT scans are associated with overall survival (OS), recurrence‐free survival (RFS), and loco‐regional recurrence‐free survival (LR‐RFS) after stereotactic body radiotherapy (SBRT) among nonsmall‐cell lung cancer (NSCLC) patients.Patients and methodsA total of 92 patients (median age: 73 yr) with stage I or IIA NSCLC were qualified for this study. A total dose of 50 Gy in five fractions was the standard treatment. Besides clinical characteristics, 24 “semantic” image features were manually scored based on a point scale (up to 5) and 219 computer‐derived “radiomic” features were extracted based on whole tumor segmentation. Statistical analysis was performed using Cox proportional hazards model and Harrell's C‐index, and the robustness of final prognostic model was assessed using tenfold cross validation by dichotomizing patients according to the survival or recurrence status at 24 months.ResultsTwo‐year OS, RFS and LR‐RFS were 69.95%, 41.3%, and 51.85%, respectively. There was an improvement of Harrell's C‐index when adding imaging features to a clinical model. The model for OS contained the Eastern Cooperative Oncology Group (ECOG) performance status [Hazard Ratio (HR) = 2.78, 95% Confidence Interval (CI): 1.37–5.65], pleural retraction (HR = 0.27, 95% CI: 0.08–0.92), F2 (short axis × longest diameter, HR = 1.72, 95% CI: 1.21–2.44) and F186 (Hist‐Energy‐L1, HR = 1.27, 95% CI: 1.00–1.61); The prognostic model for RFS contained vessel attachment (HR = 2.13, 95% CI: 1.24–3.64) and F2 (HR = 1.69, 95% CI: 1.33–2.15); and the model for LR‐RFS contained the ECOG performance status (HR = 2.01, 95% CI: 1.12–3.60) and F2 (HR = 1.67, 95% CI: 1.29–2.18).ConclusionsImaging features derived from planning CT demonstrate prognostic value for recurrence following SBRT treatment, and might be helpful in patient stratification.
Mit molekularen Photoschaltern Materialien kontrollieren
Authors: Fuhrmann Anne , Kathan Michael , Göstl Robert , Hecht Stefan 
Published: May 2017

AbstractMoleküle, die ihre Eigenschaften bei Lichtbestrahlung ändern, stehen zunehmend im Blickpunkt der Materialforscher. Denn Ort und Dauer der Lichteinwirkung sind präzise kontrollierbar, und die Schalt‐prozesse sind reversibel.
Seinerzeit und heutzutage: Scoparin aus Besenginster
Authors: Brecker Lothar 
Published: May 2017

AbstractDie Strukturaufklärung von Naturstoffen ist seit mehr als 150 Jahren ein wichtiges Forschungsgebiet österreichischer Chemiker. So haben sich zwischen 1866 und 1926 mehrere österreichische Arbeitsgruppen mit der Untersuchung des Scoparins beschäftigt.
Synthese im Blickpunkt: Benachbarte Stereozentren unter voller Kontrolle
Authors: Teichert Johannes F. 
Published: May 2017

AbstractEins von vier möglichen Stereoisomeren zweier benachbarter Stereozentren selektiv herzustellen, ist schwierig. Noch schwieriger, aber attraktiv wäre, nicht nur die beiden Zentren aufzubauen, sondern simultan die Bindung zwischen ihnen. Damit entstünden Molekülskelett und stereogene Zentren gleichzeitig. Dies leistet effizient die stereodivergente Katalyse.
Mit der GDCh in die Zukunft führen
Authors: Bürger Nicole , Kühner Susanne , Karger Gerhard 
Published: May 2017

AbstractZur zweitägigen Beratung der GDCh‐Fachgruppenvorsitzenden mit der GDCh‐Präsidentin trafen sich im Oktober vergangenen Jahres Vertreter von 24 Fachstrukturen zum zwölften Mal im Heinrich‐Fabri‐Institut in Blaubeuren. Mit dem Verkauf der Tagungsstätte durch die Universität Tübingen geht eine Ära zu Ende, die Günter Gauglitz und seine Teams mitgeprägt haben.
Winterschule für Katalyseforscher in Heidelberg
Authors: Hamann Jessica Nadine , Hermsen Marko 
Published: May 2017

AbstractJubiläum: Mitte Februar fand die zehnte „CaRLa Winter School“ in Heidelberg statt. Bei der fünftägigen Veranstaltung tauschten sich 40 Doktoranden und Postdoktoranden mit 9 Professoren aus aller Welt und Vertretern der BASF über neue Erkenntnisse der homogenen Katalyse aus. Organisiert wurde die Konferenz von den Leitern des Catalysis Research Laboratorys, Thomas Schaub (BASF) und Stephen Hashmi (Universität Heidelberg).
Reinigungsvalidierung mit überkritischem CO2
Authors: Möller Isabelle 
Published: May 2017

AbstractZu jedem Prozessschritt in der Produktion von pharmazeutischen Wirkstoffen gehört die Reinigung der verwendeten Reaktoren und anschließend die Reinigungsvalidierung. Diese ist wichtig, da sie die Qualität der Produkte sichert. Eine schnelle Alternative zur HPLC ist dabei die Online‐Extraktion und ‐Chromatographie mit überkritischen Fluiden.
Long‐term follow‐up of anterior vaginal repair: A comparison among colporrhaphy, colporrhaphy with reinforcement by xenograft, and mesh
Authors: Balzarro Matteo , Rubilotta Emanuele , Porcaro Antonio B. , Trabacchin Nicolò , Sarti Alessandra , Cerruto Maria A. , Siracusano Salvatore , Artibani Walter 
Published: May 2017

AimsTo assess the long‐term complications and outcomes in patients treated for pelvic organ prolapse (POP) with transvaginal anterior colporrhaphy (AC) alone, transvaginal naterior AC with reinforcement by using porcine Xenograft (AC‐P) (Pelvisoft® Biomesh), and transvaginal anterior repair with polypropylene mesh (AC‐M).MethodsThis was a retrospective analysis of 109/123 consecutive patients, who underwent cystocele repair: 42 AC, 19 AC‐P, and 48 AC‐M. Subjective outcomes included validated questionnaires as well as questions that had not been previously validated. Objective outcomes have been evaluated considering failure the anterior vaginal wall recurrence >2 stage POP‐Quantification. Statistical analysis included the chi‐square or Fisher exact test.ResultsThe mean follow‐up was 94.80 ± 51.72 months (19‐192 months). In all groups, the patient's personal satisfaction was high. There was no evidence of difference in outcome based on whether a biological graft was or was not performed, or whether synthetic mesh was used to reinforce the repair. Data showed a higher rate of complications in the AC‐M group (P < 0.05) that could explain the lower subjective satisfaction of these patients.ConclusionsThis study evaluated long‐term outcomes to anterior vaginal repair over a period of more than 5 years in all the groups. Our data show that anterior vaginal repair with mesh and xenograft did not improve significantly objective and subjective outcomes. Rather, prosthetic device use leads to higher rate of complications.
Stimulus‐associated urinary urges in overactive bladder syndrome
Authors: O'Connell Kathleen A. , Singer Jonathan , Rajan Sonali 
Published: May 2017

AimsAlthough anecdotal reports of urinary urgency at one's front door are common in overactive bladder syndrome (OAB), little research has been done on how one's front door and other stimuli are related to urinary symptoms. We hypothesized that individuals with OAB would have higher scores on the Urinary Cues Questionnaire, developed for this study to assess stimulus‐associated urinary urges, than those without OAB.MethodsOnline surveys were administered to 328 women age 18‐40 years recruited from a respondent panel maintained by CINT such that one‐third of the sample reported a diagnosis of OAB. The survey assessed OAB symptoms and the frequency with which participants associated 42 stimuli with the urge to urinate.ResultsPsychometric analyses showed internal consistency estimates of the Urinary Cues Questionnaire of α = 0.97 and a test‐retest correlation of 0.91. Women with OAB had significantly higher Urinary Cues Scores than those without OAB, with a t‐test showing a large effect size of d = 1.49 (95%CI 1.24, 1.74), P < 0.001.DiscussionBehavioral treatments aimed at reducing the response to cues may be useful in OAB, but more research is needed on both treatment implications and on the trajectory of symptom development.