bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oriented Morphogenesis of ZnO Nanostructures from Water‐Soluble Zinc Salts under Environmentally Mild Conditions and Their Optical Properties
Authors: Manna Joydeb , Rana Rohit Kumar 
Published: December 2011

AbstractHerein, we report a bottom‐up, mineralization strategy, which borrows key principles from biomineralization processes, to synthesize nanostructured materials. A long‐chain polyamine simultaneously mineralizes and assembles ZnO nanoparticles directly from water‐soluble zinc salts under sustainable synthesis conditions. These thus‐generated oriented structures undergo interesting morphogenesis that is controlled by changing the ratio of polyamine/Zn2+ ions. As the ratio increases, the morphology changes from a spherical shape to oval‐, dumbbell‐, and finally hexagonal‐rod‐shaped structures that contain unique hollow rod structures. Using XPS, XRD, FT‐IR, Raman spectroscopy, DLS, and confocal fluorescence microscopic analysis, we elucidate the mechanism of structural evolution; this mechanism involves the initial formation of a zinc/amine complex that is furnished with polyamine chains. These chains facilitate the condensation process to form ZnO nanoparticles and their assembly in aqueous medium at neutral pH. Further, the presence of defects in the thus‐morphogenized ZnO structures leads to blue luminescence and efficient photoinduced activity, assisted by the surface‐hole‐trapping effect of polyamines.
Exploring Meso‐/Microporous Composite Molecular Sieves with Core–Shell Structures
Authors: Qian Xufang F. , Li Bin , Hu Yuanyuan Y. , Niu Guoxing X. , Zhang D. Yahong H. , Che Renchao C. , Tang Yi , Su Dangsheng S. , Asiri Abdullah M. , Zhao Dongyuan Y. 
Published: December 2011

AbstractA series of core–shell‐structured composite molecular sieves comprising zeolite single crystals (i.e., ZSM‐5) as a core and ordered mesoporous silica as a shell were synthesized by means of a surfactant‐directed sol–gel process in basic medium by using cetyltrimethylammonium bromide (CTAB) as a template and tetraethylorthosilicate (TEOS) as silica precursor. Through this coating method, uniform mesoporous silica shells closely grow around the anisotropic zeolite single crystals, the shell thickness of which can easily be tuned in the range of 15–100 nm by changing the ratio of TEOS/zeolite. The obtained composite molecular sieves have compact meso‐/micropore junctions that form a hierarchical pore structure from ordered mesopore channels (2.4–3.0 nm in diameter) to zeolite micropores (≈0.51 nm). The short‐time kinetic diffusion efficiency of benzene molecules within pristine ZSM‐5 (≈7.88×10−19 m2 s−1) is almost retainable after covering with 75 nm‐thick mesoporous silica shells (≈7.25×10−19 m2 s−1), which reflects the greatly opened junctions between closely connected mesopores (shell) and micropores (core). The core–shell composite shows greatly enhanced adsorption capacity (≈1.35 mmol g−1) for large molecules such as 1,3,5‐triisopropylbenzene relative to that of pristine ZSM‐5 (≈0.4 mmol g−1) owing to the mesoporous silica shells. When Al species are introduced during the coating process, the core–shell composite molecular sieves demonstrate a graded acidity distribution from weak acidity of mesopores (predominant Lewis acid sites) to accessible strong acidity of zeolite cores (Lewis and Brønsted acid sites). The probe catalytic cracking reaction of n‐dodecane shows the superiority of the unique core–shell structure over pristine ZSM‐5. Insight into the core–shell composite structure with hierarchical pore and graded acidity distribution show great potential for petroleum catalytic processes.
A Novel Aptamer Developed for Breast Cancer Cell Internalization
Authors: Zhang Kejing , Sefah Kwame , Tang Lili , Zhao Zilong , Zhu Guizhi , Ye Mao , Sun Weijia , Goodison Steve , Tan Weihong 
Published: December 2011

AbstractBreast cancer affects one in eight women in the United States, with a mortality rate that is second only to lung cancer. Although chemotherapy is widely used in breast cancer treatment, its side effects remain a challenge. One way to address this problem is through drug delivery by the internalization of cell‐type‐specific probes. Although nucleic acid aptamers are excellent probes for molecular recognition, only a few studies have demonstrated that aptamers can be internalized into living cells. Therefore, herein we report the development of a cancer‐cell‐specific DNA aptamer probe, KMF2‐1a. By using the cell‐SELEX method, this aptamer was selected against breast cancer cell line MCF‐10AT1. Our results show that KMF2‐1a is internalized efficiently and specifically to the endosome of target breast cancer cells. These results indicate that KMF2‐1a is a promising agent for cell‐type‐specific intracellular delivery with both diagnostic and therapeutic implications.
Successive interference cancelation for a CDMA system with diversity reception in non‐Gaussian noise
Authors: Abuhilal H. , Hocanin A. , Bilgekul H. 
Published: December 2011

SUMMARYA large class of physical phenomenon observed in practical wireless systems exhibits non‐Gaussian behavior. The performance of many multiuser detectors can degrade substantially in the presence of such impulsive ambient noise. In this paper, multiuser detection of space coded MIMO and code division multiple access (CDMA) signals under impulsive noise with diversity reception are investigated. We analyze and derive the probability of bit error (Pb) performance of a successive interference cancelation (SIC) system under impulsive noise and maximal ratio combining. We use Middleton's class A model for the noise distribution. Furthermore, we employ post detection SIC as the robust multiuser detection technique for combating the impulsive noise at specific noise parameters in a CDMA setting. The performance of the system under power imbalance is also shown. Novel analytical derivations for both combining techniques are presented, and simulations were performed, which confirm the theoretical results. Copyright © 2011 John Wiley & Sons, Ltd.
β‐ but not γ‐secretase proteolysis of APP causes synaptic and memory deficits in a mouse model of dementia
Authors: Tamayev Robert , Matsuda Shuji , Arancio Ottavio , D'Adamio Luciano 
Published: December 2011

AbstractA mutation in the BRI2/ITM2b gene causes loss of BRI2 protein leading to familial Danish dementia (FDD). BRI2 deficiency of FDD provokes an increase in amyloid‐β precursor protein (APP) processing since BRI2 is an inhibitor of APP proteolysis, and APP mediates the synaptic/memory deficits in FDD. APP processing is linked to Alzheimer disease (AD) pathogenesis, which is consistent with a common mechanism involving toxic APP metabolites in both dementias. We show that inhibition of APP cleavage by β‐secretase rescues synaptic/memory deficits in a mouse model of FDD. β‐cleavage of APP yields amino‐terminal‐soluble APPβ (sAPPβ) and β‐carboxyl‐terminal fragments (β‐CTF). Processing of β‐CTF by γ‐secretase releases amyloid‐β (Aβ), which is assumed to cause AD. However, inhibition of γ‐secretase did not ameliorate synaptic/memory deficits of FDD mice. These results suggest that sAPPβ and/or β‐CTF, rather than Aβ, are the toxic species causing dementia, and indicate that reducing β‐cleavage of APP is an appropriate therapeutic approach to treating human dementias. Our data and the failures of anti‐Aβ therapies in humans advise against targeting γ‐secretase cleavage of APP and/or Aβ.
Designing internal evaluation for a small organization with limited resources
Authors: Baron Michelle E. 
Published: December 2011

AbstractThe chapter outlines strategies that small organizations at the early, midterm, and seasoned levels of evaluation capacity can cultivate, and offers some practical tips for evaluators on developing and maintaining internal evaluation within a small organization. The author deliberates that as organizational and evaluative skills work in tandem, members of the organization turn to the internal evaluator for support, are proactive in resolving program difficulties, and are open to future evaluations and capacity‐building efforts. © Wiley Periodicals, Inc., and the American Evaluation Association.
Geochronology of the Turkana Depression of Northern Kenya and Southern Ethiopia
Authors: Brown Francis H. , Mcdougall Ian 
Published: December 2011

AbstractMesozoic and Cenozoic sedimentary rocks in the Turkana Depression of northern Kenya and southern Ethiopia rest on basement rocks that yield K/Ar cooling ages between 433 and 522 Ma. Proven Cretaceous strata are exposed in Lokitaung Gorge in northwest Kenya. Eocene basalts and rhyolites in Lokitaung Gorge, the Nabwal Hills, and at Kangamajoj, date between 34 and 36 Ma, recording the earliest volcanism in the region. Oligocene volcanic rocks, with associated fossiliferous sedimentary strata at Eragaleit, Nakwai, and Lokone, all west of Lake Turkana, are 23 to 28 Ma old, as is the Langaria Formation east of Lake Turkana. Lower and Middle Miocene volcanic and sedimentary sequences are present both east and west of Lake Turkana, where ages from 17.9 to 9.1 Ma have been measured at many levels. Upper Miocene strata are presently known only at Lothagam, with ages ranging from 7.4 to 6.5 Ma. Deposition of Pliocene strata of the Omo Group begins in the Omo‐Turkana, Kerio, and South Turkana basins ∼4.3 Ma ago and continues in parts of those basins until nearly the present time, but with some gaps. These strata are linked through volcanic ash correlations at many levels, as are Pleistocene strata of the Omo Group (principally the Shungura, Koobi Fora, and Nachukui formations). 40Ar/39Ar dates on many volcanic ash layers within the Omo Group, supplemented by K/Ar ages on intercalated basalts and paleomagnetic polarity stratigraphy, provide excellent age control from 4.2 to 0.75 Ma, although there is a gap in the record between ∼1 Ma and 0.8 Ma. Members I to III of the Kibish Formation in the lower Omo Valley record deposition between 0.2 and 0.1 Ma ago; Member IV, correlative with the Galana Boi Formation, was deposited principally between 12 and 7 ka BP. © 2011 Wiley Periodicals, Inc.
Stable Isotope Ecology in the Omo‐Turkana Basin
Authors: Cerling Thure E. , Levin Naomi E. , Passey Benjamin H. 
Published: December 2011

AbstractStable isotopes provide an independent assessment of paleoenvironments in the Omo‐Turkana Basin. Stable isotopes track the flow of oxygen and carbon through ecosystems and accordingly are not directly related to changes in mammalian faunal composition or sedimentology. Therefore, isotope studies give insight into the paleoenvironmental conditions in which human evolutionary trends have been recorded. The development of stable isotopes as indicators of continental environmental conditions has proceeded in parallel with questions about the conditions of human environment. What was the vegetation? How hot was it? How dry? What were the diets of animals living among early humans? And most persistently, how important were “savannas” to early hominids? In this review, we take the opportunity to provide extensive background on the use of isotopes in anthropological sites. The application of stable isotope ecology to anthropological sites in the Turkana Basin has a long history, but in many ways the Omo‐Turkana Basin has been a proving ground for the development of new proxy methods for understanding tropical terrestrial environments in the Neogene and Quaternary. For that reason, we also describe some of the fundamental aspects of isotope ecology that developed outside the field of paleoanthropology. © Wiley Periodicals, Inc.
Increased gene copy number of KIT and VEGFR2 at 4q12 in primary breast cancer is related to an aggressive phenotype and impaired prognosis
Authors: Johansson Ida , Aaltonen Kristina E. , Ebbesson Anna , Grabau Dorthe , Wigerup Caroline , Hedenfalk Ingrid , Rydén Lisa 
Published: December 2011

AbstractTriple‐negative breast cancer (TNBC) is associated with poor prognosis and no targeted treatments are available for TNBC. Drugs inhibiting tyrosine kinases, such as vascular endothelial growth factor receptor 2 (VEGFR2) and KIT, have shown some promising results for patients with TNBC. The aim of the study was to investigate whether gains and/or amplifications of VEGFR2 and KIT, located at 4q12, occur in TNBC. Fluorescence in situ hybridization (FISH) was used to quantify gene copy numbers of VEGFR2 and KIT in 83 primary human breast cancers including 31 TNBCs. Gains were defined as ≥4 gene copies in >40% of the cancer cells, whereas amplification was defined as CEP >2 in more than 10% of the cancer cells. A tumor was considered FISH positive for KIT and/or VEGFR2 if it displayed copy number gain and/or amplification. Ten (32%) of the TNBCs were VEGFR2 FISH positive and nine (29%) were KIT FISH positive, whereas non‐TNBCs were FISH positive for VEGFR2 and KIT in nine (18%) cases for both genes, but no significant difference between TNBCs and non‐TNBCs was found. FISH positivity for VEGFR2 and KIT was significantly correlated (χ2 test, P < 0.001), and significantly related to ER negativity and high Nottingham histological grade (NHG). A significantly worse 5‐year breast cancer specific survival (BCSS) was seen for FISH positive cases. Increased copy number of VEGFR2 and KIT thus has the potential of functioning as a novel predictive biomarker for selected targeted therapy particularly in the difficult‐to‐treat TNBC patient category. © 2011 Wiley Periodicals, Inc.
Methods to separate observed global evapotranspiration into the interception, transpiration and soil surface evaporation components
Authors: Blyth Eleanor , Harding Richard John 
Published: December 2011

AbstractEvaporation is made up of three components: interception, soil surface evaporation and transpiration. They each have different stores of water and different characteristic timescales. It would be useful to be able to identify the relative proportions of these components at large, even global, scales for land surface model validation. The possibility of separating out the components of observed evaporation at large scales is reviewed with reference to methods used at local scales, landscape scales and scales used in remote sensing. Many of the traditional methods used require intensive measurement programmes and are unlikely to be practical at large scales. New techniques using time‐series analysis may be used to deliver a global three‐component evaporation product. Copyright © 2011 John Wiley & Sons, Ltd.
Differential expression of iron metabolism proteins in diabetic and diabetic iron‐supplemented rat liver
Authors: Silva Maísa , de Brito Magalhães Cintia Lopes , de Paula Oliveira Riva , Silva Marcelo Eustáquio , Pedrosa Maria Lucia 
Published: December 2011

AbstractDiabetes mellitus is associated with altered iron homeostasis that can potentially effect reactive oxygen species generation and contribute to diabetes‐related complications. We investigated, by quantitative polymerase chain reaction, whether the expression of liver hepcidin, ferritin, and TfR‐1 is altered in diabetes. Rats in the control (C) group received a standard diet; control iron (CI) group received a standard diet supplemented with iron; diabetic (D) group received an injection of streptozotocin; and diabetic iron (DI) group received streptozotocin and the diet with iron. Animals of the D group showed higher levels of serum iron, increased concentration of carbonyl protein, and a decrease in antioxidant status. Group D rats showed increased hepatic expression of Trf‐1 compared to the other groups. Iron supplementation reversed this increase. Hepcidin mRNA was 81% higher in DI than in C and CI rats. The results suggest that diabetes, with or without excess iron, can cause perturbations in iron status, hepcidin and Trf‐1 expression. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:123–129, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20418
Interaction and protection mechanism between li@C60 and nucleic acid bases (NABs): Performance of PM6‐DH2 on noncovalent interaction of NABs‐Li@C60
Authors: Sun Wenming , Bu Yuxiang , Wang Yixuan 
Published: December 2011

AbstractTo discuss the protection mechanism of DNA from radiation as well as assess the performance of PM6‐DH2 on noncovalent interactions, the interaction of four nucleic acid bases (NABs) such as adenine (A), cytosine (C), guanine (G), and thymine (T), with Li@C60 was extensively investigated with the‐state‐of‐art theoretical methods describing noncovalent systems, like M06‐2x, PBE‐D, and PM6‐DH2 methods. In the gas phase, the binding strength of NABs to Li@C60 from M06‐2x decreases in the sequence, G>C>A>T. As dispersion was explicitly included, PBE‐D relatively enhances the binding of A and T and corrects the sequence to, G>A>C∼T. PM6‐DH2 predicted similar binding energies to those from PBE‐D within 0.5 kcal/mol and the same binding sequence, suggesting that the PM6‐DH2 method is promising for nano‐scale systems. In the aqueous solution, binding of NABs‐Li@C60 is considerably decreased, and the M06‐2X and PM6‐D methods yield a different sequence from the gas phase, G>A>T>C. The encapsulation of Li atom results in a lower IP for Li@C60 than those of NABs, and the dominant localization of single‐occupied molecular orbital on Li@C60 moiety of the complexes NABs‐Li@C60 further indicates that an electron would be ejected from Li@C60 upon radiation and Li@C60 is therefore able to protect DNA bases from radiation. In addition, it was revealed that Li prefers coordination with the hexagonal ring at Li@C60, which clarifies the existing controversy in this respect. Finally, Yang's reduced density gradient approach clearly shows that the weak and strong noncovalent interaction regions in the complexes, NABs‐Li@C60 and (NABs‐Li@C60)+. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Artichoke polyphenols induce apoptosis and decrease the invasive potential of the human breast cancer cell line MDA‐MB231
Authors: Mileo Anna Maria , Di Venere Donato , Linsalata Vito , Fraioli Rocco , Miccadei Stefania 
Published: December 2011

AbstractThe human breast cancer cell line, estrogen receptor negative, MDA‐MB231, was used to evaluate the antitumor effect of polyphenolic extracts from the edible part of artichokes (AEs). Treatment of cancer cells reduced cell viability and inhibited cell growth in a dose‐dependent manner. Importantly, AEs did not have any effect on normal breast epithelial cell line, MCF10A. Chlorogenic acid (ChA), the most representative component of the polyphenolic fraction of artichoke, had no prominent effects on the cell death rate of MDA‐MB231 cells. The addition of AEs to the cells, rather than ChA, triggered apoptosis via a mitochondrial and a death‐receptor pathway, as shown by the activation of caspase‐9 and caspase‐8, respectively. Furthermore, an increase of the Bax:Bcl2 ratio and up‐regulation of cyclin‐dependent kinase inhibitor, p21WAF1, crucial apoptotic players, were documented. According to our data on activation of caspase‐9, a loss of mitochondrial transmembrane potential (Ψm) was shown. Cell motility and invasion capabilities were remarkably inhibited by AEs‐treatment in highly invasive MDA‐MB231 cells. In addition, a significant decrease of proteolytic activity of metalloproteinase‐2 protein (MMP‐2), involved in degrading components of the extracellular matrix, was detected. Our findings indicate that AEs reduced cell viability, inhibited cell growth, triggered apoptotic mechanisms, and showed inhibitory properties against the invasive behavior of MDA‐MB231 cancer cell line. Altogether, these data indicate the potential chemopreventive activity of artichoke polyphenolic extracts. J. Cell. Physiol. 227: 3301–3309, 2012. © 2011 Wiley Periodicals, Inc.
MAD2 depletion triggers premature cellular senescence in human primary fibroblasts by activating a P53 pathway preventing aneuploid cells propagation
Authors: Lentini Laura , Barra Viviana , Schillaci Tiziana , Di Leonardo Aldo 
Published: December 2011

AbstractThe spindle assembly checkpoint (SAC) is a cellular surveillance mechanism that ensures faithful chromosome segregation during mitosis and its failure can result in aneuploidy. Previously, it was suggested that reduction of the MAD2 gene, encoding a major component of the SAC, induced aneuploidy in human tumor cells. However, tumor cell lines contain multiple mutations that might affect or exacerbate the cellular response to Mad2 depletion. Thus, the scenario resulting by Mad2 depletion in primary human cells could be different and more complex that the one depicted so far. We used primary human fibroblasts (IMR90) and epithelial breast cells (MCF10A) to gain further insight on the effects of genomic instability caused by transient Mad2 depletion. To this aim we depleted Mad2 by RNAi to a level shown by Mad2 haplo‐insufficient cells and found that induced aneuploidy caused premature cellular senescence in IMR90 cells. IMR90 cells showed typical features of senescent cells, like senescence‐associated (SA) ${\rm {\tilde {\beta }}}$ galactosidase expression, including up‐regulation of p53 and p14ARF proteins and of p21waf1 as well, but not of p16(INK4A) cyclin‐dependent kinase (Cdk) inhibitor. In contrast, after MAD2 post‐transcriptional silencing MCF10A cells in which the INK4A/ARF locus is deleted, showed both aneuploidy and a small increase of p53 and p21waf1 proteins, but not premature cellular senescence. Finally, our results provides an explanation of how a p53 controlled pathway, involving initially p21waf1 and then p14ARF, could minimize the occurrence of genomic alterations derived from chromosome instability induced by low amounts of MAD2 protein. J. Cell. Physiol. 227: 3324–3332, 2012. © 2011 Wiley Periodicals, Inc.
Estimation of thermal dose from MR thermometry during application of nonablative pulsed high intensity focused ultrasound
Authors: O'Neill Brian E. , Karmonik Christof , Sassaroli Elisabetta , Li King C. 
Published: December 2011

AbstractPurpose:To evaluate whether MR thermometry is sufficiently fast, accurate, and spatially resolved for monitoring the thermal safety of nonablative pulsed high intensity ultrasound (pHIFU) treatments.Materials and Methods:A combination of real MR thermometry data and modeling was used to analyze the effects of temporal and spatial averaging as well as noise on the peak temperatures and thermal doses that would be measured by MR thermometry.Results:MR thermometry systematically underestimates the temperature and thermal doses during pHIFU treatment. Small underestimates of peak temperature can lead to large underestimates of thermal dose. Spatial averaging errors are small for ratios of pixel dimension to heating zone radius less than 0.25, which may be achieved by reducing the voxel size or steering the acoustic beam. Thermal dose might also be underestimated for very short, high power pulses due to temporal averaging. A simple correction factor based on the applied power and duty cycle may be applied to determine the upper bound of this effect.Conclusion:The temperature and thermal dose measured using MR thermometry during pulsed HIFU treatment is probably sufficient in most instances. Simple corrections may be used to calculate an upper bound where this is a critical factor. J. Magn. Reson. Imaging 2012;35:1169‐1178. © 2011 Wiley Periodicals, Inc.