bluuebunny/crossref_metadata_2025_split huggingface dataset:
E2F1‐dependent pathways are involved in amonafide analogue 7‐d‐induced DNA damage, G2/M arrest, and apoptosis in p53‐deficient K562 cells
Authors: Li Yiquan , Shao Jin , Shen Ke , Xu Yufang , Liu Jianwen , Qian Xuhong 
Published: May 2012

AbstractThe E2F1 gene well known is its pivotal role in regulating the entry from G1 to S phase, while the salvage antitumoral pathway which implicates it, especially in the absence of p53, is not fully characterized. We therefore attempted to identify the up‐ and down‐stream events involved in the activation of the E2F1‐dependent pro‐apoptotic pathway. For this purpose, a amonafide analogue, 7‐d (2‐(3‐(2‐(Dimethylamino)ethylamino)propyl)‐6‐(dodecylamino)‐1H‐benzo[de]isoquinoline‐1,3(2H)‐dione) was screened, which exhibited high antitumor activity against p53‐deficient human Chronic Myelogenous Leukemia (CML) K562 cells. Analysis of flow cytometry and western blots of K562 cells treated with 7‐d revealed an appreciable G2/M cycle arrest and apoptosis in a dose and time‐dependent manner via p53‐independent pathway. A striking increase in “Comet tail” formation and γ‐H2AX expression showed that DNA double strand breaks (DSB) were caused by 7‐d treatment. ATM/ATR signaling was reported to connect E2F1 induction with apoptosis in response to DNA damage. Indeed, 7‐d‐induced G2/M arrest and apoptosis were antagonized by ATM/ATR signaling inhibitor, Caffeine, which suggested that ATM/ATR signaling was activated by 7‐d treatment. Furthermore, the increased expression of E2F1, p73, and Apaf‐1 and p73 dissociation from HDM2 was induced by 7‐d treatment, however, knockout of E2F1 expression reversed p73, Apaf‐1, and p21Cip1/WAF1 expression, reactivated cell cycle progression, and inhibited 7‐d‐induced apoptosis. Altogether our results for the first time indicate that 7‐d mediates its growth inhibitory effects on CML p53‐deficient cells via the activation of an E2F1‐dependent mitochondrial and cell cycle checkpoint signaling pathway which subsequently targets p73, Apaf‐1, and p21Cip1/WAF1. J. Cell. Biochem. 113: 3165–3177, 2012. © 2012 Wiley Periodicals, Inc.
Studies on the interaction of CdTe QDs with bovine serum albumin
Authors: Liu Peng , Liu Yisi , Wang Qisui 
Published: May 2012

AbstractBACKGROUND: Quantum dots (QDs) have attracted much attention in biological and medical applications. In particular, the interaction of QDs with bovine serum albumin (BSA) is crucial, and has been systematically investigated by various spectroscopic techniques under the physiological conditions.RESULTS: The effects of ionic strength and pH on the interaction of CdTe QDs with BSA were studied by changing NaCl concentration and pH in mixed solution and making fluorescence spectroscopic measurements. The Stern‐Volmer quenching constant (Ka) of different ionic strength and pH were calculated, and information on the structural features of BSA were discussed by means of circular dichroism (CD) spectrum.CONCLUSION: Both fluorescence (FL) and circular dichroism (CD) results indicated that hydrophobic and electrostatic interactions play a major role in the binding reaction, and the nature of quenching is static, resulting in forming QDs‐BSA complexes. Copyright © 2012 Society of Chemical Industry
Participation in unprofessional behaviors among hospitalists: A multicenter study
Authors: Reddy Shalini T. , Iwaz James A. , Didwania Aashish K. , O'Leary Kevin J. , Anderson R. Andy , Humphrey Holly J. , Farnan Jeanne M. , Wayne Diane B. , Arora Vineet M. 
Published: May 2012

AbstractBACKGROUND:Unprofessional behaviors undermine the hospital learning environment and quality of patient care.OBJECTIVE:To quantify perceptions of, and participation in, unprofessional behaviors among hospitalists.DESIGN:Observational survey study.SETTING:Three academic health centers.SUBJECTS:Hospitalists.MEASUREMENTS:Observation, participation in, and perceptions of unprofessional behaviors.RESULTS:Response rate was 76% (77/101). Nearly all behaviors were perceived as unprofessional (“unprofessional” or “somewhat unprofessional” on the Likert scale). Participation in egregious behaviors (ie, falsifying records) was low (<5%). The most frequent behaviors reported were having personal conversations in patient corridors (67.1%), ordering a test as “urgent” to expedite care (62.3%), and making fun of other physicians (40.3%). Four factors accounted for 76% of survey variance: (1) making fun of others; (2) learning environment (eg, texting during conferences); (3) workload management (eg, celebrating a blocked‐admission); and (4) time pressure (eg, signing out work early). Hospitalists with less clinical time (<50% full‐time equivalents [FTE]) were more likely to report making fun of others (β = 0.94 [95% CI 0.32–1.56], P = 0.004). Younger hospitalists (β = 0.87 [95% CI 0.07–1.67], P = 0.034) and those with administrative time (β = 0.61 [95% CI 0.11–1.10], P = 0.017) were more likely to report participating in workload management behaviors. Hospitalists who work night shifts were more likely to report participating in time‐pressure behaviors (β = 0.67 [95% CI 0.17–1.17], P = 0.010). Workload management and learning environment varied by site.CONCLUSION:While hospitalist participation in unprofessional behaviors is low, job characteristics (clinical, administrative, nights), age, and site were associated with different types of unprofessional behavior that may affect the learning environment and patient care. Journal of Hospital Medicine 2012;. © 2012 Society of Hospital Medicine
Changes in the linear relationship of ENSO–PDO under the global warming
Authors: Kwon MinHo , Yeh Sang‐Wook , Park Young‐Gyu , Lee Yoon‐Kyoung 
Published: May 2012

AbstractWe examine changes in El Niño and Southern Oscillation (ENSO)/Pacific Decadal Oscillation (PDO) relationship under the global warming using coupled climate models participated in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). The temporal structure for the ENSO–PDO relationship is changed remarkably. The relationship between ENSO and PDO during the boreal winter (December, January and February) becomes stronger so that there would be more frequent in phase occurrence of ENSO and PDO (i.e. El Niño—a positive phase of PDO or La Niña—a negative phase of PDO). As PDO could constructively interfere with the ENSO‐related climate when ENSO and PDO are in phase, in the future one may expect stronger climate signal because of ENSO in the midlatitude. The IPCC AR4 model also shows that the Pacific North America‐like pattern is slightly shifted eastward and much stronger. We also discuss the possible reason for these changes. Copyright © 2012 Royal Meteorological Society
Holocene palaeoflood events recorded by slackwater deposits along the lower Jinghe River valley, middle Yellow River basin, China
Authors: Huang Chun Chang , Pang Jiangli , Zha Xiaochun , Zhou Yali , Su Hongxia , Zhang Yuzhu , Wang Hengsong , Gu Hongliang 
Published: May 2012

AbstractPalaeoflood slackwater deposits (SWDs), are the natural record of overbank flooding and are often found within aeolian loess‐soil profiles along the river valleys of the middle Yellow River basin. These pedo‐stratigraphic sequences are studied using a multi‐disciplinarily approach to reconstruct Holocene hydro‐climatic variations. Our field investigations along the lower Jinghe River valley have identified palaeoflood SWDs at several sites along the riverbanks based on sedimentological criteria. Analytical results, including magnetic susceptibility, particle‐size distribution and concentrations of chemical elements, indicate that these well‐sorted palaeoflood SWD beds were deposited from the suspended sediment load in floodwaters. We identify two episodes of extraordinary palaeoflood events along the Jinghe River valley. These hydro‐climatic events were dated to 4200–4000 and 3200–2800 a BP, by using the optically stimulated luminescence method in combination with archaeological dating of retrieved anthropogenic remains, and with pedo‐stratigraphic correlations with the previously studied Holocene pedo‐stratigraphy in the Jinghe River drainage basin. The flooding events are therefore considered to be a regional expression of known climatic events in the northern hemisphere and demonstrate Holocene climate was far from stable. This study provides important data in understanding the interactions between regional hydro‐climatic systems and global change in semi‐arid and sub‐humid regions. Copyright © 2012 John Wiley & Sons, Ltd.
Stro‐1+ stromal cells have stem‐like features in giant cell tumor of bone
Authors: Lan Jie , Liu Xiaoguang , Rong Wei , Wei Feng , Jiang Liang , Yu Haiyan , Dang Gengting , Liu Zhongjun 
Published: May 2012

AbstractBackgroundGiant cell tumor of bone (GCTB) is an aggressive benign bone tumor with poor prognosis whose neoplastic component is stromal cells (SCs). Tumor stem‐like cells (TSCs) have been demonstrated as precursors for tumor genesis and growth. The aim of this study is to identify TSCs in GCTB.MethodsStro‐1+ and Stro‐1− cells were isolated by fluorescence‐activated cell sorting (FACS). Stem‐like properties of both Stro‐1+ and Stro‐1− subpopulations were assessed using MTT colorimetric assays, cell cycle analyses, sphere formation assays, and differentiation assays. Molecular profiles were analyzed by flow cytometry, immunofluorescence, and qRT‐PCR.ResultsThe existence of rare Stro‐1+ cells was confirmed in vitro using FACS and in vivo by immunohistochemistry. These Stro‐1+ cells exhibited higher proliferative and cisplatin‐resistant potentials than Stro‐1− cells. In serum‐free suspension cultures, Stro‐1+ SCs could form cell spheres and maintain self‐renewal. Furthermore, Stro‐1+ SCs could differentiate into two mesenchymal lineage cells: osteoblasts and adipocytes. Cell surface markers CD44, CD117, and CD133 and stem cell‐associated genes OCT3/4, NANOG, and ABCG2 were significantly higher in the Stro‐1+ subpopulation.ConclusionsThis study demonstrates that Stro‐1+ SCs in GCTB possess stem‐like biological and molecular phenotypes, indicating that they are the TSCs of GCTB. J. Surg. Oncol. 2012; 106:826–836. © 2012 Wiley Periodicals, Inc.
Short and long term degradation behaviour of Mg–1Ca magnesium alloys and protective coatings based on plasma‐chemical oxidation and biodegradable polymer coating in synthetic body fluid
Authors: Rosemann P. , Schmidt J. , Heyn A. 
Published: May 2012

AbstractThe main problem limiting the application of magnesium alloys as biodegradable implant material is its high degradation rate. In order to slow down the corrosion rate an extrusion process and specific coating systems based on plasma‐chemical oxidation (PCO) and organic dip coating with poly(L‐lactid‐co‐caprolacton) (PLLC) were applied on Mg–1Ca magnesium alloy. The additional PLLC coating is used to delay the start of substrate corrosion, while the purpose of the PCO coating is to decrease the substrate corrosion rate. The corrosion behaviour was investigated in synthetic body fluid (SBF) through measurement of the hydrogen evolution rate in long term tests and polarisation and electrochemical noise measurements in short term tests. The results showed significant differences between the cast and extruded alloys and a decrease of the corrosion rate due to corrosion product formation. The combination of both coating systems resulted in a significant delay of metal substrate corrosion and all coating systems showed good correlation between short and long term tests. The combination of the three investigation methods provides the possibility to gain more information about the degradation behaviour and break down of protective coatings.
A functional polymorphism C‐1310G in the promoter region ofKu70/XRCC6is associated with risk of renal cell carcinoma
Authors: Wang Wei , Pan Xuping , Huo Xinying , Yan Fu , Wang Meilin , Wang Dingxian , Gao Yanqin , Cao Qiang , Luo Dewei , Qin Chao , Yin Changjun , Zhang Zhengdong 
Published: May 2012

AbstractThe DNA repair geneKu70plays a key role in the DNA double strand break (DSB) repair system. Defects in DSB repair capacity can lead to genomic instability. We hypothesized that theKu70C‐1310G polymorphism (rs2267437) was associated with risk of renal cell carcinoma (RCC). We genotyped theKu70C‐1310G polymorphism in a case–control study of 620 patients and 623 controls in a Chinese population and assessed the effects of C‐1310G polymorphism on RCC susceptibility and survival. We then examined the functionality of this polymorphism. Compared with theKu70‐1310CC genotype, the CG and CG/GG genotypes had a significantly increased risk of RCC [adjusted odds ratio (OR) = 1.47, 95% confidence interval (CI) = 1.16–1.87 for CG and OR = 1.47, 95% CI = 1.16–1.86 for CG/GG]. However, the C‐1310G polymorphism did not influence the survival of RCC. The in vivo experiments with normal renal tissues revealed statistically significantly lowerKu70mRNA expression in samples with CG/GG genotypes relative to those with the CC genotype (P < 0.05). In vitro luciferase assays in various cell lines showed lower luciferase activity for the −1310G allele than for the −1310C allele. These results suggest that theKu70C‐1310G polymorphism is involved in the etiology of RCC and thus may be a marker for genetic susceptibility to RCC in Chinese populations. Larger studies are warranted to validate our findings. © 2012 Wiley Periodicals, Inc.
Simple wideband microstrip ring bandpass filter by utilizing forced harmonic suppression and direct feed line coupling
Authors: Liu Y. , Chang K. 
Published: May 2012

AbstractA compact wideband microstrip ring bandpass filter is demonstrated in this article by means of forced harmonic suppression of a single square ring resonator with the absence of the feed line coupling gaps. Via‐hole and slit‐gap are incorporated as the forced boundary conditions of the resonator in the filter design. Both simulation and measurement results are provided and shown in good agreement. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1968–1970, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26935
Design considerations for compact microstrip resonant cells dedicated to efficient branch‐line miniaturization
Authors: Kurgan P. , Filipcewicz J. , Kitlinski M. 
Published: May 2012

AbstractA conventional compact microstrip resonant cell (CMRC) has been thoroughly investigated to enhance its slow‐wave properties and subsequently ensure an efficient miniaturization of a microstrip circuit.The geometry of a classic CMRC has been improved in terms of slow‐wave effect in two progressive steps: (i) a single‐element topology has been replaced with a double‐element one and (ii) a high‐impedance section has been refined by means of an optimized meander line characterized by the minimal number of discontinuities. Vital usefulness of the novel CMRC in the process of microstrip circuit miniaturization has been proven and experimentally validated on the basis of a compact 3‐dB branch‐line coupler illustrating the possibilities of the approach. A prototype structure has been designed to mimic the performance of a classic coupler, simultaneously presenting a substantial 85% surface area reduction. The measured in‐band results are in excellent accordance with theoretical characteristics, whereas the broadband performance depicts an additional phenomenon, that is, the efficient suppression of unwanted signals up to the sixth harmonic. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1949–1954, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26980
Are Green Vehicles Worth the Extra Cost? The Case of Diesel‐Electric Hybrid Technology for Urban Delivery Vehicles
Authors: Krutilla Kerry , Graham John D. 
Published: May 2012

AbstractA central question for environmental policy is whether the long‐term benefits of energy‐saving technologies are sufficient to justify their short‐term costs, and if so, whether financial incentives are needed to stimulate adoption. The fiscal effects of incentivizing new technologies, and the revenue effects of using the technology, are also policy relevant, given current fiscal constraints. This study evaluates the economic and fiscal effects of promoting diesel‐electric hybrid technology in urban delivery vehicles, an application supported by U.S. policymakers. An economic model is used to simulate the conditional probability density functions of the net present values (NPVs) of diesel electric hybrids annually from 2012 to 2030. The NPV time paths, which reflect fuel price, environmental, and technology trends, show the expected dates that hybrids become economically viable, and allow an evaluation of the net benefits of hybrid technology as an investment over the entire simulation horizon. The NPV distributions are computed for five stakeholder classes, including transportation firms, parties benefiting from reduced externality damages, state and local governments, and the larger society. The analysis shows that hybrid technology investment does not appear to be justified from a societal perspective at a 7 percent discount rate, but the probability for positive net returns increases substantially at a 3 percent rate.
Insulating polyimide films containing n‐type perylenediimide moieties
Authors: Damaceanu Mariana‐Dana , Rusu Radu‐Dan , Musteata Valentina‐Elena , Bruma Maria 
Published: May 2012

AbstractOxadiazole‐containing polyperyleneimides were prepared by high‐temperature solution polycondensation reaction of an aromatic diamino‐oxadiazole with a mixture of two dianhydrides, one containing a perylene moiety and the other containing a hexafluoroisopropylidene unit. Flexible films having good mechanical properties were made therefrom. The structure of the polymer films was confirmed using X‐ray photoelectron spectroscopy. Some polymer films were subjected to measurements of electrical insulating properties. The variation of the real and imaginary parts of the dielectric permittivity with frequency and temperature was recorded. The values of the dielectric constant, dielectric loss and specific resistance were obtained at 25 °C and in the frequency domain from 1 Hz to 130 kHz. The dielectric spectroscopy data showed distinct γ and β subglass transitions for these polymers at low activation energies. Electronic conduction through a hopping mechanism in these polyimide films was determined from AC conductivity measurements. Copyright © 2012 Society of Chemical Industry
Improved efficiency of hybrid solar cell based on thiols‐passivated CdS quantum dots and poly(3‐hexythiophene)
Authors: Liu Xinmei , Jiang Yang , Lan Xinzheng , Zhang Yugang , Liu Chao , Li Junwei , Wang Binbin , Yu Yongqiang , Wang Wenjun 
Published: May 2012

AbstractA bulk‐heterojunction hybrid solar cell based on CdS quantum dots (QDs) as electron acceptor and P3HT as donor was fabricated for the first time. The CdS QDs synthesized by a one‐pot method had good crystallinity and stability. The hybrid thin film of CdS‐QDs and conjugated polymer was made by simple spin‐coating deposition of CdS‐QDs/P3HT composite solution on ITO substrates and then treated by bidentate ligand ethanedithiol. Under AM1.5G illumination, the power‐conversion efficiency (PCE) of the thiol‐treated monolayer film was more than three times higher than that of the untreated device. The hybrid solar cell based on the assembled trilayer blend film with ethanedithiol by a layer‐by‐layer approach exhibited a further improved PCE of 0.86%, which was sixfold higher than that of the thiol‐treated monolayer device. The results can be explained via ethanedithiol effectively displacing the existing stearate ligands on the surface of QDs in situ and connecting nanoparticles by its end function group, shortening the interdot space and thus improving electron transport between the QDs. The morphology of the thiol‐treated blend film was briefly investigated.
Fabrication of Cu2ZnSnS4 absorbers by sulfurization of Sn‐rich precursors
Authors: Ge Jie , Yu Wenlei , Cao Hong , Jiang Jinchun , Ma Jianhua , Yang Lihong , Yang Pingxiong , Hu Zhigao , Chu Junhao 
Published: May 2012

AbstractCu2ZnSnS4 (CZTS) absorbers were grown by sulfurization of the Sn‐rich precursors that were cosputtered from a CuSn target (2 in.) and a ZnS target (2 in.). The excess Sn in the precursor could limit the decomposition of CZTS during the long sulfurization process at 510 °C. The sulfurized CZTS film cosputtered with CuSn 45 W and ZnS 70 W exhibits the intended bandgap of 1.53 eV, main Raman mode at 335.5 cm−1 and a slightly Sn‐rich composition. As the sputtering power of the CuSn target was increased from 45 to 60 W, the corresponding films consisted of a CZTS phase and several Sn‐rich phases (SnS/Sn2S3/Cu4Sn7S16). Conversely, when this sputtering power was reduced to 35 W, the resultant film consisted of a CZTS phase and a ZnS secondary phase. Besides, Raman scattering shows that the increased sputtering power of the CuSn target is related with the redshift and the increased FWHMs of primary Raman modes for the resultant films. X‐ray diffraction data show the (112)‐oriented growth and lattice expansion for the obtained CZTS films.
Effects of boron–nitrogen pair on the electronic properties of zigzag graphene nanoribbon
Authors: Wang Zhiyong , Zhao Shihua , Xiao Jianrong 
Published: May 2012

AbstractThe geometry structures and electronic properties of zigzag graphene nanoribbons (ZGNRs) with boron–nitrogen (BN) pair edge‐doping are investigated by performing first‐principles calculations based on density functional theory. The calculated results show that the BN pair substitutional doping at the edge changes the conducting characteristic of ZGNR to a half‐metallic one with increasing concentration of boron (nitrogen) dopants, which may be attributed to the changes of the ionic potential difference between boron and nitrogen atoms located at the edge of the ZGNRs. It is found that the concentration of dopants at the edge regulate the electronic properties of ZGNRs. It is predicted that the theoretical results may be valuable in the design of GNR‐based spintronics devices.
Factors influencing Northern Hemisphere winter mean atmospheric circulation anomalies during the period 1960/61 to 2001/02
Authors: Greatbatch R. J. , Gollan G. , Jung T. , Kunz T. 
Published: May 2012

AbstractInfluences from the Tropics, the stratosphere and the specification of observed sea surface temperature and sea‐ice (SSTSI) on Northern Hemisphere winter mean circulation anomalies during the period 1960/61 to 2001/02 are studied using a relaxation technique applied to the ECMWF model. On interannual time‐scales, the Tropics strongly influence the Pacific sector but also the North Atlantic sector, although weakly. The stratosphere is found to be influential on the North Atlantic Oscillation (NAO) on interannual time‐scales but is less important over the Pacific sector. Adding the observed SSTSI to the tropical relaxation runs generally improves the model performance on interannual time‐scales but degrades/enhances the model's ability to capture the 42‐year trend over the Pacific/Atlantic sector. While relaxing the stratosphere to the reanalysis fails to capture the trend over the whole 42‐year period, the stratosphere is shown to be influential on the upward trend of the NAO index from 1965 to 1995, but with reduced amplitude compared to previous studies. Influence from the Tropics is found to be important for the trend over both time periods and over both sectors although, across all experiments, we can account for only 30% of the amplitude of the hemispheric trend. Copyright © 2012 Royal Meteorological Society