bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoinduced Charge‐Carrier Generation in Epitaxial MOF Thin Films: High Efficiency as a Result of an Indirect Electronic Band Gap?
Authors: Liu Jinxuan , Zhou Wencai , Liu Jianxi , Howard Ian , Kilibarda Goran , Schlabach Sabine , Coupry Damien , Addicoat Matthew , Yoneda Satoru , Tsutsui Yusuke , Sakurai Tsuneaki , Seki Shu , Wang Zhengbang , Lindemann Peter , Redel Engelbert , Heine Thomas , Wöll Christof
Published: May 2015

For inorganic semiconductors crystalline order leads to a band structure which gives rise to drastic differences to the disordered material. An example is the presence of an indirect band gap. For organic semiconductors such effects are typically not considered, since the bands are normally flat, and the band‐gap therefore is direct. Herein we show results from electronic structure calculations demonstrating that ordered arrays of porphyrins reveal a small dispersion of occupied and unoccupied bands leading to the formation of a small indirect band gap. We demonstrate herein that such ordered structures can be fabricated by liquid‐phase epitaxy and that the corresponding crystalline organic semiconductors exhibit superior photophysical properties, including large charge‐carrier mobility and an unusually large charge‐carrier generation efficiency. We have fabricated a prototype organic photovoltaic device based on this novel material exhibiting a remarkable efficiency.
Effect of convergent–divergent flow on thermal and crystallization properties of PP/MWCNTs nanocomposites
Authors: Yin Xiaochun , Yu Zhongwei , Zhang Guizhen , Yang Zhitao , Xu Baiping
Published: May 2015

A melt‐mixing process based on convergent–divergent flow has been used to prepare PP/MWCNT composites with a self‐built convergent–divergent die (C‐D die) composed of different numbers of convergent plates. Dynamic extensional deformation was generated in the C‐D die, which improved the mixing effect and mixing efficiency of the composites during extrusion. The C‐D die acted as a mixer for composites when mounted onto a capillary rheometer. The residence time of PP/MWCNTs melt in the extensional flow field is adjusted by changing the numbers of convergent plates and the velocity of the ram. The intensity of extensional flow field is controlled by the structure of the convergent plate and the ram velocity. Influences of convergent–divergent flow on PP/MWCNTs composites were characterized in terms of transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). TEM results showed that MWCNTs disperse more homogeneously with the increase of convergent plates. DSC showed that the crystallinity of PP/MWCNTs composites increased and the crystallization temperature shifted to higher temperature with the increase of the numbers of the convergent plates. TGA showed that the thermal stability of composites improved remarkably. The decomposition temperature increases from 381 to 408.2°C when the numbers of convergent plates increased from 2 to 8. In addition, the increase of ram velocity also has the same influences on the dispersion of MWCNTs in the resin and the properties of PP/MWCNTs nanocomposites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42330.
The Evolution of Cash Transfers inIndonesia: Policy Transfer and National Adaptation
Authors: Kwon Huck‐ju , Kim Woo‐rim
Published: May 2015

Cash transfers became a subject of international policy transfer, but the underlying policy process is far more complex than simple policy diffusion. In order to understand the development of cash transfers inIndonesia, it is necessary to examine the long‐term policy evolution in the context of national politics. This paper analyses the policy evolution of cash transfers in Indonesia, focusing on the policy decision process at the national level since theAsian economic crisis. It tracks three critical conjunctures of social protection for the poor in which Indonesia tried to adapt cash transfer schemes and institutional frameworks, and eventually consolidated the social protection system. Cash transfers have been adapted inIndonesia in keeping with the strong political motivations of top policymakers for popular support in the context of democratisation, but policy transfers of cash transfers provided an important impetus for the development of social protection system inIndonesia.
Age‐related Epstein–Barr virus‐positive mucocutaneous ulcer: a case report
Authors: Magalhaes Marco , Ghorab Zeina , Morneault Julien , Akinfolarin Josephine , Bradley Grace
Published: May 2015

Key Clinical Message

The oral manifestations of EBV‐positive mucocutaneous ulcers have a worrisome clinical appearance but relatively benign clinical course, responding well to conservative treatment. Elderly patients who develop an unexplained, persistent ulcer of the oral mucosa should have the lesion examined for EBV.
Room Temperature Ring Expansion of N‐Heterocyclic Carbenes and BB Bond Cleavage of Diboron(4) Compounds
Authors: Pietsch Sabrina , Paul Ursula , Cade Ian A. , Ingleson Michael J. , Radius Udo , Marder Todd B.
Published: May 2015

We report the isolation and detailed structural characterization, by solid‐state and solution NMR spectroscopy, of the neutral mono‐ and bis‐NHC adducts of bis(catecholato)diboron (B2cat2). The bis‐NHC adduct undergoes thermally induced rearrangement, forming a six‐membered ‐BCNCC‐N‐heterocyclic ring via CN bond cleavage and ring expansion of the NHC, whereas the mono‐NHC adduct is stable. Bis(neopentylglycolato)diboron (B2neop2) is much more reactive than B2cat2 giving a ring expanded product at room temperature, demonstrating that ring expansion of NHCs can be a very facile process with significant implications for their use in catalysis.
High‐Sensitivity Cardiac Troponin T in Stable Patients Undergoing Pharmacological Stress Testing
Authors: Wongpraparut Nattawut , Piyophirapong Sudarat , Maneesai Adisak , Sribhen Kosit , Krittayaphong Rungroj , Pongakasira Rungtiwa , White Harvey D.
Published: May 2015

Background

Acute changes in high‐sensitivity troponin T (hs‐TnT) are induced by myocardial ischemia during exercise stress testing, but there are no reports of pharmacological stress testing.

Hypothesis

The pattern of troponin release by myocardial ischemia–induced pharmacological stress testing differs according to the ischemic burden in stable patients.

Methods

In total, 250 patients with suspected coronary artery disease underwent pharmacological stress magnetic resonance imaging (MRI). The amount and degree of myocardial ischemia on MRI and ischemic outcomes at 6 months were determined. hs‐TnT levels were measured at baseline and 1 and 3 hours after testing. The 6‐month clinical outcome was prespecified.

Results

Fifty‐one patients had moderate to severe myocardial ischemia (group A), and 199 patients had no or mild myocardial ischemia (group B). hs‐TnT levels were significantly higher in group A than B at baseline (11 vs 8 pg/mL, P = 0.016) and at 1 hour (12 vs 8 pg/mL, P = 0.009) and 3 hours after testing (12 vs 9 pg/mL, P = 0.012). Baseline hs‐TnT levels of ≥14 pg/mL showed a 43% sensitivity and 77% specificity in predicting moderate to severe ischemia by MRI (P = 0.03; area under the curve: 0.608, P = 0.017). Patients administered dobutamine had a higher acute change in hs‐TnT levels 3 hours after testing than did those administered adenosine (21 vs 0 pg/mL, P < 0.001). There was a trend toward a higher incidence of myocardial infarction in patients with baseline hs‐TnT levels of ≥14 pg/mL.

Conclusions

hs‐TnT levels are significantly higher in patients with moderate to severe than no or mild myocardial ischemia.
Prior high‐risk HPV testing and Pap test results for 427 invasive cervical cancers in China's largest CAP‐certified laboratory
Authors: Zheng Baowen , Li Zaibo , Griffith Christopher C. , Yan Shanshan , Chen Congde , Ding Xiangdong , Liang Xiaoman , Yang Huaitao , Zhao Chengquan
Published: May 2015

BACKGROUND

Cervical cancer and its precursor lesions are caused by a persistent high‐risk human papillomavirus (hrHPV) infection. hrHPV testing has been reported to have higher sensitivity than Papanicolaou (Pap) testing for the detection of cervical precursor lesions. However, limited data are available for prior human papillomavirus (HPV) testing results for patients later diagnosed with invasive cervical cancer, especially in countries lacking a national cervical cancer screening program such as China. This study investigated prior hrHPV testing results for patients with invasive cervical cancer in China.

METHODS

Cases with a histologic diagnosis of invasive cervical carcinoma were retrieved from Guangzhou KingMed Diagnostics (the largest independent pathology laboratory in China); prior hrHPV and Pap test results obtained within the year before the cancer diagnosis were recorded.

RESULTS

HPV testing was negative in 7.5% of 427 cases of invasive cervical carcinoma, including squamous cell carcinoma (5%) and adenocarcinoma (25%). In 155 cervical cancer cases with prior hrHPV and Pap testing, the negative rate for Pap testing was 1.9%, and the negative rate for HPV was 9.7%. Furthermore, when only cases of adenocarcinoma (n = 18) were examined, both the hrHPV‐negative rate and the Pap‐negative rate were higher at 33% and 5.6%, respectively.

CONCLUSIONS

These data demonstrate a considerable prior hrHPV‐negative rate and a lower prior Pap‐negative rate in patients with invasive cervical carcinoma (especially adenocarcinoma) from a population of women without access to an established screening program. Cancer (Cancer Cytopathol) 2015;123:428‐34. © 2015 American Cancer Society.
Poor cell block adequacy rate for molecular testing improved with the addition of Diff‐Quik–stained smears: Need for better cell block processing
Authors: Harada Shuko , Agosto‐Arroyo Emmanuel , Levesque Jessica A. , Alston Evan , Janowski Karen M. , Coshatt Gina M. , Eltoum Isam A.
Published: May 2015

BACKGROUND

In the era of personalized medicine, requests for molecular testing of specimens obtained with minimally invasive procedures such as fine‐needle aspiration have been increasing. Although cell blocks (CBs) are the recommended specimens for molecular testing, their performance has not been well analyzed. The objective of this study was to assess the frequency and types of samples deemed unsatisfactory for molecular testing (quantity not sufficient [QNS]).

METHODS

One year after the implementation of careful monitoring of QNS cases, cases submitted for lung cancer molecular testing were analyzed for the QNS rate. When the cases were rejected for the inadequacy of CBs of cytology specimens, air‐dried, Diff‐Quik (DQ)–stained smears were reviewed and used if they were adequate. The QNS rates were compared across 4 specimen categories: large resection, small biopsy, CB alone, and CB with DQ smears.

RESULTS

One hundred seventy‐six cases were studied, and 45 (25.6%) were unsatisfactory. Only 1 of 73 large resection specimens was rejected because of decalcification. The QNS rate for small biopsy specimens was 35.9% (28 of 78), whereas 64% (16 of 25) of cytology cases ordered on CBs were rejected. In combination with DQ smears, the QNS rate of cytology specimens was 32% (8 of 25), which was a significant improvement over CBs only (P = .024) and was not significantly different from the QNS rate for small biopsies (P = .671).

CONCLUSIONS

The utilization of DQ‐stained smears for molecular testing improves the adequacy of cytologic samples and provides a minimally invasive alternative to surgical biopsy when molecular analysis of tumor material is necessary. Cancer (Cancer Cytopathol) 2015;123:480–7. © 2015 American Cancer Society.
High‐Indexed Pt3Fe Nanocatalysts and Their Enhanced Catalytic Performance in Dual Organic Reactions
Authors: Wang Chenyu , Lin Cuikun , Zhao Bo , Zhang Lihua , Kumbhar Amar , Fan Guangyin , Sun Kai , Zhang Jun , Chen Shuang , Fang Jiye
Published: May 2015

The synthesis of noble metal nanocrystals terminated with high‐index facets has received increasing attention due to the remarkable improvement in their catalytic performance. Introducing a transition metal to noble metals (bimetallic nanocrystals) could result in a reduced cost and potentially improve properties. Keeping in mind both of these advantages, we have developed a new synthetic approach to fabricate size‐controlled Pt3Fe concave nanocubes using a high‐temperature organic solution system containing oleylamine and oleic acid. It further demonstrates that the particle size and concavity could be controlled by a number of parameters such as the ratio of oleylamine and oleic acid, the physicochemical properties of the metal carbonyl, the metal valence in the precursor, and the ratio of metal precursors. Catalytic tests show that the high‐index‐surface‐terminated ≈12 nm Pt3Fe concave nanocubes exhibit superior performance in both the hydrogenation of styrene and reduction of 4‐nitrophenol in comparison with their counterparts.
In‐plane structure of ferecrystalline compounds
Authors: Falmbigl Matthias , Alemayehu Matti B. , Merrill Devin R. , Beekman Matt , Johnson David C.
Published: May 2015

This work provides a review on the in‐plane structure of a recently established subgroup of misfit layer compounds, namely ferecrystals. While misfit layer compounds can be described as layered intergrowths of two distinct substructures in which only one axis of the subunits remains incommensurate, for ferecrystals both constituents retain independent in‐plane crystalline structures. This is accompanied by extensive rotational disorder, a key feature of ferecrystals. Our comparison of the in‐plane structures of misfit layer compounds and ferecrystals suggests that the weaker registration between the subunits in ferecrystals allows the synthesis of a wider variety of compounds, varying both the range of constituents, their mismatch and their thicknesses. The in‐plane structures of the individual constituents in ferecrystalline compounds exhibit interesting features such as 2D‐symmetry, size induced structural transformation, misfit parameters that depend on the component thicknesses, and pairing distortions of constituent layers.
A new anti‐collision protocol based on information of collided tags in RFID systems
Authors: Bagheri Nasour , Alenaby Parvin , Safkhani Masoumeh
Published: May 2015

Radio frequency identification (RFID) technology has recently become an integral part of a wide range of applications. One of the challenges in RFID systems is the tag anti‐collision issue, for which several anti‐collision tag identification protocols have been proposed. This paper proposes a novel slotted ALOHA‐based RFID tag anti‐collision algorithm which can be employed for tag identification. The main idea of this algorithm is to use the information available in collision slots, called collided data, to identify tags uniquely. For this purpose, the collision slots that include only two tags are selected. Then, the non‐conflict bits in these slots are used to possibly identifying the tags.

Because in the proposed algorithm readers use both single slots and also the collision slots for tag identification, the performance is increased significantly compared with other protocols.

Results of the study indicate that in the proposed algorithm, the optimal frame size for an individual tag number is equal to the half of tags number and the efficiency of the proposed protocol is improved to about 73%. Copyright © 2015 John Wiley & Sons, Ltd.
Raman Spectroscopy as a Superior Tool To Understand the Synthetic Pathway of Cu2FeSnS4 Nanoparticles
Authors: Zhou Binbin , Yan Xiunan , Li Pan , Yang Liangbao , Yu Daoyang
Published: May 2015

The quaternary chalcogenide Cu2FeSnS4 is important and interesting owing to its many advantageous characteristics for photovoltaic and optoelectronic applications, such as a suitable direct band gap (1.0–1.5 eV), low toxicity, and a relatively high abundance of the elements in the Earth's crust. To date, most of the reports on Cu2FeSnS4 have focused on the synthetic method and optical properties, and few studies have comprehensively and systematically reported the growth mechanism of Cu2FeSnS4 nanoparticles. Therefore, we have synthesized Cu2FeSnS4 nanocrystals by a simple hot‐injection method and performed detailed characterizations. Raman spectroscopy is a characterization tool to differentiate the mixed‐composition phases in the synthetic pathway of Cu2FeSnS4 nanocrystals, which cannot be efficiently distinguished by X‐ray diffraction. A possible synthesis mechanism for Cu2FeSnS4 has been proposed.
A Disk‐Like CoII3DyIII4 Coordination Cluster Exhibiting Single Molecule Magnet Behavior
Authors: Loukopoulos Edward , Berkoff Benjamin , Abdul‐Sada Alaa , Tizzard Graham J. , Coles Simon J. , Escuer Albert , Kostakis George E.
Published: May 2015

The employment of (E)‐4‐(2‐hydroxy‐3‐methoxybenzylideneamino)‐2,3‐dimethyl‐1‐phenyl‐1,2‐dihydropyrazol‐5‐one (HL) for the first time in 3d/4f chemistry, without any co‐ligand, provides access to a disk‐like heptanuclear CoII3DyIII4 coordination cluster displaying single molecule magnetism (SMM) behavior. The topology of this compound has hitherto not been observed in CoII/DyIII chemistry.
AuCl3– and AuCl3–Phenylacetylene‐Catalyzed Glycosylations by Using Glycosyl Trichloroacetimidates
Authors: Roy Rashmi , Palanivel Ashok Kumar , Mallick Asadulla , Vankar Yashwant D.
Published: May 2015

Glycosylations of armed and disarmed trichloroacetimidate‐based glycosyl donors were carried out by using the AuCl3–phenylacetylene relay catalyst system. The effectiveness of this catalytic system was also compared with that of using AuCl3 alone as a catalyst. Glycosylations with these catalysts proceeded efficiently at room temperature within 5–45 min. Excellent diastereoselectivity was obtained for the glycosylation of 2‐O‐acetyl‐protected disarmed glycosyl donors, whereas armed glycosyl trichloroacetimidates gave rise to a mixture of anomeric glycosides. Acid‐sensitive nucleophiles such as Fmoc‐serine tert‐butyl ester or Fmoc‐threonine tert‐butyl ester successfully underwent the glycosylations, albeit in moderate yields, under mild conditions at room temperature.
Prediction study and application of wind power development based on filtering error threshold
Authors: Zhang Ziqi , Zhang Rui , Fang Da , Wang Jianzhou
Published: May 2015

As a clean and renewable energy source, wind energy has been increasingly gaining global attention. Wind speed forecasting is of great significance for wind energy domain: planning and design of wind farms, wind farm operation control, wind power prediction, power grid operation scheduling, and more. Many wind speed forecasting algorithms have been proposed to improve forecast accuracy. In terms of such factors, in this article, a novel hybrid wind speed forecasting method was proposed based on Kalman filter and Generalized regression neural network as well as the idea of filtering error threshold in data preprocessing. The proposed models can implement long‐term wind speed forecasting with higher precision and reliability compared with single method and conventional approach, as demonstrated by several cases study using daily average wind speed samples collected in western China in a given year. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1536–1546, 2015
Identification of SPAG9 as a novel JAK2 fusion partner gene in pediatric acute lymphoblastic leukemia with t(9;17)(p24;q21)
Authors: Kawamura Machiko , Taki Tomohiko , Kaku Hidefumi , Ohki Kentaro , Hayashi Yasuhide
Published: May 2015

We have identified a novel SPAG9‐JAK2 fusion in a B‐cell precursor acute lymphoblastic leukemia (ALL) with t(9;17)(p24;q21) and a poor outcome, using paired‐end transcriptome sequencing. Homozygous and hemizygous deletions
of CDKN2A/2B, and hemizygous deletions of PAX5, BTG1, CDK6, ADARB2, and IKZF1 were also identified by multiple ligation‐dependent probe amplification and single nucleotide polymorphism array analyses. Having both a tyrosine kinase‐activating rearrangement and genomic lesions affecting lymphoid transcription factors suggested that the leukemia was of the Philadelphia chromosome (Ph)/BCR‐ABL1‐like ALL subtype and that JAK2 inhibitors might be able to overcome this aggressive ALL with SPAG9‐JAK2. © 2015 Wiley Periodicals, Inc.
Comparison of melanoma incidence and trends among youth under 25 years in Australia and England, 1990–2010
Authors: Wallingford Sarah C. , Iannacone Michelle R. , Youlden Danny R. , Baade Peter D. , Ives Alexander , Verne Julia , Aitken Joanne F. , Green Adèle C.
Published: May 2015

White populations in Australia and England share many genetic and phenotypic characteristics due to common ancestry, but Australians experience far higher rates of melanoma due to higher ambient ultraviolet radiation (UVR) levels. To gain insight into the role of UVR on melanoma development early in life, we used national cancer registration data and compared recent incidence rates and long‐term trends of primary invasive cutaneous melanoma in Australian and English youth aged 0–24 years diagnosed 1990–2010. Incidence rates and standardized rate ratios (SRRs) with 95% confidence intervals (CIs) for 2006–2010 were calculated and incidence trends across the whole period were examined using JoinPoint regression. In Australian youth, overall melanoma incidence was double that in English youth (2.2 and 1.1 per 100,000, respectively). While melanoma rates were similarly rare among children <10 years in both countries, in subsequent 5‐year age groups, incidence was significantly higher in Australia compared to England. Melanoma incidence among 15–24 year olds significantly increased by more than 2% per year in both sexes in England. However, after an initial non‐significant increase, Australian rates for this older age group significantly decreased by 6.0% (95% CI, −8.2 to −3.8) per year in females from 1997 and decreased by 12.4% (95% CI, −20.3 to −3.8) per year in males from 2004. Long‐standing primary prevention strategies targeted at curbing UVR exposure appear to have been effective in mitigating incidence trends in Australian youth, but decreases in incidence in English youth are yet to be observed.
Recent Advances in Counter Electrodes for Thiolate‐mediated Dye‐sensitized Solar Cells
Authors: Zhang Taihong , Liu Yanfang , Yun Sining
Published: May 2015

Dye‐sensitized solar cells (DSSCs) based on disulfide/thiolate (T2/T−) redox couples have attracted remarkable attention due to their high efficiency and low cost. As an indispensible part of DSSCs, counter electrode (CE) design plays a crucial role in high efficiency DSSCs. This mini‐review paper selectively reviews the recent advances in T‐mediated DSSCs using novel CE (namely cathode) materials, mainly including noble metal platinum (Pt), carbon materials, transition metal compounds (TMCs), polymers, and hybrids, thus highlighting the merits and demerits of alternative Pt catalysts, and the prospects and challenges of Pt‐free CEs for the development of high‐performance and low‐cost DSSCs.
Impact of Changing Irrigation Patterns on Saltwater Dynamics of Soil in Farmlands and their Shelterbelts in the Irrigated Zone of Kalamiji Oasis
Authors: Zhao Xinfeng , Xu Hailiang , Zhang Peng , Bai Yuan , Zhang Qingqing
Published: May 2015

In this study, the effects of large‐scale drip irrigation on the distribution of soil moisture and salt levels of farmlands (three cotton fields and one orchard) and their shelterbelts were investigated in Kalamiji Oasis in the lower reaches of Tarim River, north‐west China. The following conclusions were drawn: (i) in Kalamiji Oasis, the groundwater level declined at a rate of 0.5 m yr−1 as a result of the popularization of drip irrigation technology. Furthermore, the groundwater was shallower in non‐irrigation than in irrigation seasons, with an average decline of groundwater level of more than 1 m being observed during irrigation seasons. This indicates that farmers take up water from the groundwater for supplemental irrigation; (ii) the soil salinity in shelterbelts was significantly higher than that in farmland (p < 0.01). This indicates the role of biodrainage in the salt control process; (iii) under the present drip irrigation practice, and without expecting results of more detailed studies, it is recommended to implement flood irrigation probably once a year in order to preserve the shelterbelts and to stimulate salt leaching. Copyright © 2015 John Wiley & Sons, Ltd.
Comparison of Drip‐ and Furrow‐Irrigated red Pepper Yield, Yield Components, Quality and net Profit Generation
Authors: Sezen S.Metin , Yazar Attila , Şengül Haydar , Baytorun Nafi , Daşgan Yildiz , Akyildiz Asiye , Tekin Servet , Onder Derya , Ağçam Erdal , Akhoundnejad Yelderem , Gügercin Özkan
Published: May 2015

The effects of different irrigation regimes on yield and quality and net profit of processing red pepper irrigated with drip and furrow irrigation systems under field conditions in the Mediterranean region of Turkey were evaluated over two years. The treatments for drip consist of full irrigation (DFI), deficit irrigation DDI‐75, D‐PRD‐50, DF‐PRD‐50 and DDI‐50, and for furrow: full irrigation (FFI), fixed alternative furrow (FAF‐50) and PRD furrow (FPRD‐50). FAF‐50 and FPRD‐50 received 50% of water applied to FFI. In FAF‐50 the same furrows were irrigated while FPRD‐50 was irrigated alternately. Irrigation methods and levels had a significant effect on total yield and some quality parameters of red pepper. Drip produced higher red pepper yields than furrow. The highest yield in the drip system was obtained from the DFI treatment followed by DDI‐75, DDI‐50 and DF‐PRD‐50 treatments. Although D‐PRD‐50, DF‐PRD‐50 and DDI‐50 received the same amount of water, D‐PRD‐50 resulted in a higher yield. In furrow treatments, FFI resulted in the highest yield, followed by FPRD‐50 and FAF‐50. Water productivity (WP) decreased with increasing water quantity for both irrigation systems. Fruit weight, size and flesh thickness were higher in the DFI and FFI treatments. Full irrigation treatments (DFI and FFI) generated the highest net income. Copyright © 2015 John Wiley & Sons, Ltd.
Thermal denaturation behavior of collagen fibrils in wet and dry environment
Authors: Suwa Yosuke , Nam Kwangwoo , Ozeki Kazuhide , Kimura Tsuyoshi , Kishida Akio , Masuzawa Toru
Published: May 2015

We have developed a new minimally invasive technique––integrated low‐level energy adhesion technique (ILEAT)––which uses heat, pressure, and low‐frequency vibrations for binding living tissues. Because the adhesion mechanism of the living tissues is not fully understood, we investigated the effect of thermal energy on the collagen structure in living tissues using ILEAT. To study the effect of thermal energy and heating time on the structure of the collagen fibril, samples were divided in two categories–wet and dry. Further, atomic force microscopy was used to analyze the collagen fibril structure before and after heating. Results showed that collagen fibrils in water denatured after 1 minute at temperatures higher than 80°C, while partial denaturation was observed at temperatures of 80°C and a heating time of 1 min. Furthermore, complete denaturation was achieved after 90 min, suggesting that the denaturation rate is temperature and time dependent. Moreover, the collagen fibrils in dry condition maintained their native structure even after being heated to 120°C for 90 min in the absence of water, which specifically suppressed denaturation. However, partial denaturation of collagen fibrils could not be prevented, because this determines the adhesion between the collagen molecules, and stabilizes tissue bonding. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 538–545, 2016.
Investigation of structural resorption behavior of biphasic bioceramics with help of gravimetry, μCT, SEM, and XRD
Authors: de Wild Michael , Amacher Fabienne , Bradbury Christopher R. , Molenberg Aart
Published: May 2015

Resorbable bone substitute materials are widely used for bone augmentation after tumor resection, parallel to implant placement, or in critical size bone defects. In this study, the structural dissolution of a biphasic calcium phosphate bone substitute material with a hydroxyapatite (HA)/tricalcium phosphate (β‐TCP) ratio of 60/40 was investigated by repeatedly placing porous blocks in EDTA solution at 37 °C. At several time points, the blocks were investigated by SEM, µCT, and gravimetry. It was found that always complete 2–3 µm sized grains were removed from the structure and that the β‐TCP is dissolved more rapidly. This selective dissolution of the β‐TCP grains was confirmed by XRD measurements. The blocks were eroded from the outside toward the center. The structure remained mechanically stable because the central part showed a delayed degradation and because the slower dissolving HA grains preserved the integrity of the structure. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 546–553, 2016.
Effect of modification degree of nanohydroxyapatite on biocompatibility and mechanical property of injectable poly(methyl methacrylate)‐based bone cement
Authors: Quan Changyun , Tang Yong , Liu Zhenzhen , Rao Minyu , Zhang Wei , Liang Peiqing , Wu Nan , Zhang Chao , Shen Huiyong , Jiang Qing
Published: May 2015

The objective of this study is to prepare a biocompatible nanohydroxyapatite/poly(methyl methacrylate) (HA/PMMA) composite bone cement, which has good mechanical property and can be used for vertebroplasty. Up to 40 wt % of nanohydroxyapatite (nano‐HA) in the power, which was surface modified with poly(methylmethacrylate‐co‐γ‐methacryloxypropyl timethoxysilane) [P(MMA‐co‐MPS)] copolymer, was incorporated into the composite bone cement. The content of P(MMA‐co‐MPS) on the surface of nano‐HA (18.7%, 22.8%, and 26%) was determined through thermogravimetric analysis (TGA). The morphology of biomineralized surface of composite bone cement was observed under scanning electron microscope (SEM). The mechanical measurements of the composite cements implied that the interfacial interaction between the HA and PMMA matrix may be greatly enhanced after surface modification of HA. Biochemical assays indicated that the HA/PMMA bone cement had no cytotoxicity and induced no hemolysis. The cell adhesion and alkaline phosphatase (ALP) activity assays indicated that the biocompatibility of HA/PMMA bone cement could be promoted, demonstrating that it can be used as an ideal weight‐bearing bone repair materials on clinical application. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 576–584, 2016.
Development of a ubiquitously transferrable silver‐nanoparticle‐loaded polymer nanosheet as an antimicrobial coating
Authors: Ito Keisuke , Saito Akihiro , Fujie Toshinori , Miyazaki Hiromi , Kinoshita Manabu , Saitoh Daizoh , Ohtsubo Shinya , Takeoka Shinji
Published: May 2015

Ultra‐thin polymer films (nanosheets) fabricated by a layer‐by‐layer (LbL) method possess unique properties such as high flexibility, adhesive strength, and transparency, and can be peeled off from a substrate and attached to various surfaces via a water‐soluble supporting film. Therefore, flexible and transferrable LbL nanosheets are convenient tools as coating materials. Here, we fabricated a novel antimicrobial coating material by embedding silver nanoparticles (AgNPs) in an LbL nanosheet composed of layers of chitosan and sodium alginate (Ag‐LbL nanosheet) by means of a photo‐reduction method. Optimizing the amount of irradiated energy applied led to robust antimicrobial efficacy against methicillin‐resistant Staphylococcus aureus (MRSA), sufficient to meet ISO standards (ISO 22196), while maintaining the flexibility and adhesive potency of the LbL nanosheet. Thus, the Ag‐LbL nanosheet is a promising coating material that can provide antimicrobial efficacy to various surfaces. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 585–593, 2016.
Prenatal developmental safety of functional polyurethanes for cardiovascular implants
Authors: Gu Yongjiang , Sun Fan , Xie Xingyi , Wu Xiangyang , Zhang Ze , Guidoin Robert , Fu Qiang , Zhong Yinping , Zhao Changsheng
Published: May 2015

Historically, polyurethanes have been regarded as promising materials for cardiovascular implants such as vascular grafts and heart valves. Their biocompatibility has been thoroughly investigated. However, their developmental toxicity is seldom reported. We recently developed two polycarbonate urethanes with polyethylene glycol side chains capped with epoxy or amino groups that can further react with specific biomolecules. Both materials in microfibrillar morphology were subjected to saline extraction at 70°C to prompt material hydrolysis. Proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, and gel permeation chromatography all confirmed the degradation of the polyurethanes. The saline extracts containing the degradation products were administered to Sprague‐Dawley female rats on day 7 to 16 of gestation via tail vein injection at a dose of 5 mL/kg/day. No maternal toxicity was observed. No external, skeletal, and visceral malformations in fetuses were found associated with the test materials, implying their safety to both adult rats and the offspring. Further investigations for applications in vascular grafts are under way. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 606–614, 2016.
Cytocompatibility evaluation ofNiMnSn meta‐magnetic shape memory alloys for biomedical applications
Authors: Guiza‐Arguello Viviana R. , Monroe James A. , Karaman Ibrahim , Hahn Mariah S.
Published: May 2015

Recently, magnetic shape memory alloys (MSMAs) have emerged as an interesting extension to conventional shape memory alloys (SMAs) due to their capacity to undergo reversible deformation in response to an externally applied magnetic field. Meta‐magnetic SMAs (M‐MSMAs) are a class of MSMAs that are able to transform magnetic energy to mechanical work by harnessing a magnetic‐field induced phase transformation, and thus have the capacity to impose up to 10 times greater stress than conventional MSMAs. As such, M‐MSMAs may hold substantial promise in biomedical applications requiring extracorporeal device activation. In the present study, the cytotoxicity and ion release from an Ni50Mn36Sn14atomic percent composition M‐MSMA were evaluated using NIH/3T3 fibroblasts. Initial studies showed that the viability of cells exposed to NiMnSn ion leachants was 60 to 67% of tissue culture polystyrene (TCP) controls over 10 to 14 days of culture. This represents a significant improvement in cytocompatibility relative to NiMnGa alloys, one of the most extensively studied MSMA systems, which have been reported to induce 80% cell death in only 48 h. Furthermore, NiMnSn M‐MSMA associated cell viability was increased to 80% of TCP controls following layer‐by‐layer alloy coating with poly(allylamine hydrochloride)/poly(acrylic acid) [PAH/PAA]. Ion release measures revealed that the PAH/PAA coatings decreased total Sn and Mn ion release by 50% and 25%, respectively, and optical microscopy evaluation indicated that the coatings reduced NiMnSn surface oxidation. To our knowledge, this study presents the first cytotoxicity evaluation of NiMnSn M‐MSMAs and lays the groundwork for their further biological evaluation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 853–863, 2016.
Early cell response to contact with biomaterial's surface
Authors: Komorowski Piotr , Walkowiak‐Przybyło Magdalena , Walkowiak Bogdan
Published: May 2015

Most biomaterials at present have sufficient mechanical properties; however compliance with standards for biocompatibility is often not sufficient in clinical practice. This may be due to the complexity of biological systems in general and the diversity of individual responses to these materials by implant recipients. Significant improvement of biocompatibility must involve surface modification of implants, which in the future will make it possible to introduce individually selected types of surface modification for individual recipients. The key to this technology seems to be understanding the processes occurring at the site of contact of the implant with the tissue. Processes resulting from the stress generated by the contact of the biomaterial surfaces were observed with endothelial cells line EA.hy926, and it was demonstrated that differently modified surfaces of medical steel (polished medical steel and medical steel coated with Parylene C and nanocrystalline diamond) cause diverse cellular response in cells grown on these surfaces, on both the cellular (cell morphology and cell survival) and molecular (transcriptome and proteome profiles) levels. The herein presented observations are a good starting point not only for further research and the development of far‐reaching personalization of medical implants, but also to study the potential use of cells as a specific sensor capable of recognizing different surfaces with which these cells come into contact. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 880–893, 2016.
Characterization and cytocompatibility of a new injectable multiphasic bone substitute based on a combination of polysaccharide gel‐coated OSPROLIFE® HA/TTCP granules and bone marrow concentrate
Authors: Pierini Michela , Lucarelli Enrico , Duchi Serena , Prosperi Susanna , Preve Eleonora , Piccinini Marzio , Bucciotti Francesco , Donati Davide
Published: May 2015

The purpose of this study was to examine the in vitro cytocompatibility of a novel injectable multiphasic bone substitute (MBS) based on polysaccharide gel‐coated OSPROLIFE® hydroxyapatite (HA)/tetracalcium phosphate (TTCP) granules combined with bone marrow concentrate (BMC). Polysaccharide gel‐coated granules loaded in syringe were combined with BMC diluted in ionic crosslinking solution. The product was then maintained in culture to investigate the cytocompatibility, distribution, and osteogenic differentiation function of cells contained in the BMC. The in vitro cytocompatibility was assessed after 0, 24, and 96 h from the injectable MBS preparation using the LIVE/DEAD® staining kit. The results highlighted that cells remained viable after combination with the polysaccharide gel‐coated granules; also, viability was maintained over time. The distribution of the cells in the product, observed using confocal microscopy, showed viable cells immersed in the polysaccharide gel formed between the granules after ionic crosslinking. The mesenchymal stromal cells (MSC) contained in the injectable MBS, the basic elements for bone tissue regeneration, were able to differentiate toward osteoblasts, producing an osteogenic matrix as evidenced by alizarin red‐s (AR‐S) staining. In conclusion, we found that the injectable MBS may have the potential to be used as a bone substitute by applying a “one‐step” procedure in bone tissue engineering applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 894–902, 2016.
Comparative sensitivity of commercial tests for hepatitis E genotype 3 virus antibody detection
Authors: Avellon Ana , Morago Lucia , Garcia‐Galera del Carmen Maria , Munoz Milagros , Echevarría Jose‐Manuel
Published: May 2015

Hepatitis E virus (HEV) acute infection is often diagnosed only by anti‐HEV IgM ELISA methods, whose sensitivity varies, according to different reports. Reports assessing the specificity of commercial assays for anti‐HEV IgG testing are scarce, and estimates of sensitivity and specificity are both controversial. The aim of this work is to assess the sensitivity of different commercial techniques for HEV genotype 3 antibody (anti‐HEV) IgM and IgG detection in entirely specific sample panels including both high and low antibody concentrations. The anti‐HEV IgM and IgG ELISA methods compared were: DSI, Mikrogen, Wantai, Euroimmun, MP, and Dia.pro. The rapid test All Diag was also included in the anti‐HEV IgM comparison. Our results show that low anti‐HEV IgM concentrations were better detected by DSI, Mikrogen, and All Diag, these tests being the most sensitive in our study. Euroimmun, MP and Dia.pro gave concordant results, showing lower sensitivity than the others. Regarding anti‐HEV IgG our results revealed similar anti‐HEV IgG sensitivity. Furthermore, there was a striking overall lack of concordance among the results. We present a thorough review of previous comparative reports, with particular reference to the anti‐HEV IgG comparison, since published results differ from ours. This discrepancy may be related to the improved versions of the tests for MP and Dia.pro that we employed. J. Med. Virol. 87:1934–1939, 2015. © 2015 Wiley Periodicals, Inc.
Diversity of 1,213 hepatitis C virus NS3 protease sequences from a clinical virology laboratory database in Marseille university hospitals, southeastern France
Authors: Hajji Hind , Aherfi Sarah , Motte Anne , Ravaux Isabelle , Mokhtari Saadia , Ruiz Jean‐Marie , Poizot‐Martin Isabelle , Tourres Christian , Tivoli Natacha , Gérolami René , Tamalet Catherine , Colson Philippe
Published: May 2015

Infection with hepatitis C virus (HCV) represents a major public health concern worldwide. Recent therapeutic advances have been considerable, HCV genotype continuing to guide therapeutic management. Since 2008, HCV genotyping in our clinical microbiology laboratory at university hospitals of Marseille, Southeastern France, has been based on NS3 protease gene population sequencing, to allow concurrent HCV genotype and protease inhibitor (PI) genotypic resistance determinations. We aimed, first, to analyze the genetic diversity of HCV NS3 protease obtained from blood samples collected between 2003 and 2013 from patients monitored at university hospitals of Marseille and detect possible atypical sequences; and, second, to identify NS3 protease amino acid patterns associated with decreased susceptibility to HCV PIs. A total of 1,213 HCV NS3 protease sequences were available in our laboratory sequence database. We implemented a strategy based on bioinformatic tools to determine whether HCV sequences are representative of our local HCV genetic diversity, or divergent. In our 2003–2012 HCV NS3 protease sequence database, we delineated 32 clusters representative of the majority HCV genetic diversity, and 61 divergent sequences. Five of these divergent sequences showed less than 85% nucleotide identity with their top GenBank hit. In addition, among the 294 sequences obtained in 2013, three were divergent relative to these 32 previously delineated clusters. Finally, we detected both natural and on‐treatment genotypic resistance to HCV NS3 PIs, including a substantial prevalence of Q80K substitutions associated with decreased susceptibility to simeprevir, a second generation PI. J. Med. Virol. 87:1921–1933, 2015. © 2015 Wiley Periodicals, Inc.
Simultaneous extraction and quantification of lamotrigine, phenobarbital, and phenytoin in human plasma and urine samples using solidified floating organic drop microextraction and high‐performance liquid chromatography
Authors: Asadi Mohammad , Dadfarnia Shayessteh , Haji Shabani Ali Mohammad , abbasi Bijan
Published: May 2015

A novel and simple method based on solidified floating organic drop microextraction followed by high‐performance liquid chromatography with ultraviolet detection has been developed for simultaneous preconcentration and determination of phenobarbital, lamotrigine, and phenytoin in human plasma and urine samples. Factors affecting microextraction efficiency such as the type and volume of the extraction solvent, sample pH, extraction time, stirring rate, extraction temperature, ionic strength, and sample volume were optimized. Under the optimum conditions (i.e. extraction solvent, 1‐undecanol (40 μL); sample pH, 8.0; temperature, 25°C; stirring rate, 500 rpm; sample volume, 7 mL; potassium chloride concentration, 5% and extraction time, 50 min), the limits of detection for phenobarbital, lamotrigine, and phenytoin were 1.0, 0.1, and 0.3 μg/L, respectively. Also, the calibration curves for phenobarbital, lamotrigine, and phenytoin were linear in the concentration range of 2.0–300.0, 0.3–200.0, and 1.0–200.0 μg/L, respectively. The relative standard deviations for six replicate extractions and determinations of phenobarbital, lamotrigine, and phenytoin at 50 μg/L level were less than 4.6%. The method was successfully applied to determine phenobarbital, lamotrigine, and phenytoin in plasma and urine samples.
An iterative approach to respiratory self‐navigated whole‐heart coronary MRA significantly improves image quality in a preliminary patient study
Authors: Ginami Giulia , Bonanno Gabriele , Schwitter Juerg , Stuber Matthias , Piccini Davide
Published: May 2015

Purpose

In respiratory self‐navigated coronary MRA, the selection of a reference position may have a direct effect on image quality. While end‐expiration is commonly used as reference, it may be ill defined in cases of irregular breathing. Here, an iterative self‐navigation approach that operates without a reference position was implemented and tested in healthy volunteers and patients.

Methods

Data were acquired in 15 healthy volunteers and in 23 patients. Images obtained with end‐expiratory self‐navigation were compared with those obtained with the iterative approach that incorporates cross‐correlation to iteratively minimize a global measure of respiratory displacement. Vessel sharpness, length, signal‐to‐noise ratio (SNR), and contrast‐to‐noise ratio (CNR) were evaluated while differences in breathing patterns between the two sub‐groups were assessed, too.

Results

Vessel sharpness and length were similar for both methods in healthy volunteers. In patients, a significant improvement in vessel sharpness and length was obtained using the iterative approach. SNR and CNR remained constant. While end‐expiration was the most frequent respiratory phase in healthy volunteers (57.6 ± 16.2%), intermediate respiratory phases (43.4 ± 30.1%) were predominantly found in patients.

Conclusion

An iterative approach to respiratory motion correction in self‐navigation may lead to significant improvements in coronary MRA image quality in patients with a less consistent end‐expiratory respiratory phase. Magn Reson Med 75:1594–1604, 2016. © 2015 Wiley Periodicals, Inc.
Urinary biomarkers of chronic allograft nephropathy
Authors: Cassidy Hilary , Slyne Jennifer , O'Kelly Patrick , Traynor Carol , Conlon Peter J. , Johnston Olwyn , Slattery Craig , Ryan Michael P. , McMorrow Tara
Published: May 2015

Purpose

Chronic allograft nephropathy (CAN) is widely accepted as the leading cause of renal allograft loss after the first year post transplantation. This study aimed to identify urinary biomarkers that could predict CAN in transplant patients.

Experimental design

The study included 34 renal transplant patients with histologically proven CAN and 36 renal transplant patients with normal renal function. OrbiTrap MS was utilized to analysis a urinary fraction in order to identify other members of a previously identified biomarker tree . This novel biomarker pattern offers the potential to distinguish between transplant recipients with CAN and those with normal renal function.

Results

The primary node of the biomarker pattern was reconfirmed as β2 microglobulin. Three other members of this biomarker pattern were identified: neutrophil gelatinase‐associated lipocalin, clusterin, and kidney injury biomarker 1. Significantly higher urinary concentrations of these proteins were found in patients with CAN compared to those with normal kidney function.

Conclusions and clinical relevance

While further validation in a larger more‐diverse patient population is required to determine if this biomarker pattern provides a potential means of diagnosing CAN by noninvasive methods in a clinical setting, this study clearly demonstrates the biomarkers’ ability to stratify patients based on transplant function.