bluuebunny/crossref_metadata_2025 huggingface dataset:
Histological and Clinical Features of Primary and Recurrent Periocular Basal Cell Carcinoma
Authors: Ben Simon Guy J. , Lukovetsky Semion , Lavinsky Fabio , Rosen Nahum , Rosner Mordechai
Published: April 2012

Background. Basal cell carcinoma (BCC) is the most common malignancy of the eyelids. Medial canthal BCCs tends to recur more often. Purpose. To evaluate the clinical and histological features of primary and recurrent periocular BCC, in order to identify any existing associations. Methods. Data from 87 patients (71 primary and 16 recurrent) were analyzed in this study. All patients underwent tumor excision with frozen section margin control at the Goldschleger Eye Institute between 1/1995 to 12/1997. Statistical analysis was performed to identify possible associations between histological and clinical characteristics of primary and recurrent BCC. Main Outcome Measures. Anatomical location, clinical presentation, and histology of peri-ocular BCC. Results. No association was found between histopathological and clinical characteristics of BCC. Similar features with regard to eyelid location and histology were found in primary and recurrent peri-ocular BCCs, whereas recurrent BCCs tended to involve a greater eyelid extent with a longer duration of symptoms. Medial canthal BCCs, morpheaform, or sclerosing histology were not more common in the recurrent BCC group. Conclusions. Similar clinical and histological characteristics were noted in primary and recurrent periocular BCC, implying that incomplete surgical excision rather than anatomical location or histological features is the main cause for recurrence.
The Theory for J-Hermitian Subspaces in a Product Space
Authors: Sun Huaqing , Qi Jiangang
Published: April 2012

This paper is concerned with the theory for J-Hermitian subspaces.
The defect index of a J-Hermitian subspace is defined, and a formula
for the defect index is established; the result that every J-Hermitian subspace
has a J-self-adjoint subspace extension is obtained; all the J-self-adjoint
subspace extensions of a J-Hermitian subspace are characterized. This theory
will provide a fundamental basis for characterizations of J-self-adjoint extensions
for linear nonsymmetric expressions on general time scales in terms of
boundary conditions, including both differential and difference cases.
Closed Sets
Authors: Navaneethakrishnan M. , Alwarsamy S.
Published: April 2012

We define Closed sets and discuss their properties. Using these sets, we characterize and .
Atom Economy: a Challenge for Enhanced Synthetic Efficiency
Authors: Trost Barry M.
Published: April 2012

The sections in this article are

Vinylidenes

Cycloisomerization of Hydroxyalkynes

Reconstitutive Condensation

Redox Isomerization

Allyl Alcohols

Ruthenacyclopentadiene Intermediates

Ruthenacyclopentene Intermediates

Intermolecular Alkene‐Alkyne Coupling

Butenolide Formation and Related Reactions

Pyran Formation

Intramolecular Alkene–Alkyne Coupling

[5 + 2] Cycloaddition

Vinyl Ketones as Alkyne Partners

AllylicC–HInsertion

Reactions of Alkenes

Allene–Alkene Coupling

Heterocycles via Allene–Alkene Coupling

Conclusion

Acknowledgments
Cyclopalladated ferrocenylimine as an efficient catalyst for the syntheses of diarylmethane derivatives
Authors: Yu Ajuan , Li Xiangdong , Peng Dongpo , Wu Yangjie , Chang Junbiao
Published: April 2012

The cyclopalladated ferrocenylimine adducts Ia, Ib, Ic were evaluated in the Suzuki cross‐coupling reaction of benzyl halides with arylboronic acids. The tricyclohexylphosphine adduct Ia exhibited highly catalytic activity for the coupling of aryl and heteroaryl boronic acids containing various functional groups with benzylic bromides and chlorides (up to 99% yield), furnishing diarylmethane derivatives with low catalyst loading (1 mol%). It is worth noting that catalyst Ia can be reused eight times without losing its catalytic activity. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and properties of biodegradable network poly(ether‐urethane)s from L‐lysine triisocyanate and poly(alkylene glycol)s
Authors: Nagata Minoru , Oi Akito , Sakai Wataru , Tsutsumi Naoto
Published: April 2012

Biodegradable network poly(ether‐urethane) films with different hydrophilicity were prepared from L‐lysine triisocyanate (LTI) and poly(ethylene glycol) (PEG), poly(1,4‐tetramethylene glycol) (PTMG) or poly (propyrene glycol) (PPG) with the molecular weights of 250–2000 g mol−1. Prepolymers prepared by a melt‐polycondensation were cast from tetrahydrofuran solution and heated at 65–80°C for 9 h, then postpolymerized at 150–180°C for 10–20 min to form a network. The resultant films were transparent to opaque and insoluble in water and organic solvents. These network films were fully characterized by FTIR, density measurement, wide‐angle X‐ray scattering (WAXS), differential scanning calorimetry, dynamic mechanical analysis, and tensile tests. WAXS intensity curves of LTI/PEG‐1000 and LTI/PEG‐2000 exhibited crystalline peaks due to PEG segments, while those of all other network films did amorphous halos. The molecular weights (Mw) between cross‐links increased, while the cross‐linking density decreased with increasing the Mws of the poly(alkylene glycol)s. Mechanical properties were strongly affected by the type and molecular weights of poly(alkylene glycol)s used. The weight losses of the LTI/PEG series network films that were degraded in a phosphate buffer solution (pH 7.2) at 37°C and the equilibrium water content in distilled water at 20°C were much larger than those of LTI/PTMG and LTI/PPG series ones. In contrast, LTI/PTMG‐1000 and LTI/PPG‐1000 network films absorbed 150–216% of organic solvents such as benzene and toluene under equilibrium state at 20°C. The use of poly(alkylene glycol)s with different types and the MWs allowed the preparation of novel network poly(ether‐urethane) films with a broad range of properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Rheokinetics of crosslinkable poly(vinyl acetate) emulsion and diethylene triamine
Authors: Lu J. , Easteal A. J. , Bhattacharyya D. , Edmonds N. R. , Bolt C.
Published: April 2012

The study of the rheological behavior associated with the crosslinking process of epoxy‐functionalized poly(vinyl acetate) emulsion and diethylene triamine showed that the system was reactive and very sensitive to temperature. Gelation times and gelation temperatures were determined from the abrupt changes of the viscoelastic material functions G′, G″, and η* in time sweeps and temperature sweeps. Isothermal kinetics models of the crosslinking process based on the isoconversional method predicted the relationship of curing rate, degree of conversion, reaction nature and kinetic parameters, and temperature. The temperature dependence of the rate constants was found to be described by the Arrhenius relationship. The temperature dependencies of G′, G″, and η* were found to be frequency independent at the gel point, Tgel, providing a fingerprint for determining Tgel of the crosslinkable systems. The variation of G′ and G″ with frequency followed the power laws showing G′ = A′ωb and G″ = A″ωc through the frequency sweep. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and Biological Evaluation of Phenyl Substituted 1H‐1,2,4‐Triazoles as Non‐Steroidal Inhibitors of 17β‐Hydroxysteroid Dehydrogenase Type 2
Authors: Al‐Soud Yaseen A. , Marchais‐Oberwinkler Sandrine , Frotscher Martin , Hartmann Rolf W.
Published: April 2012

A series of disubstituted‐1H‐1,2,4‐triazole derivatives was synthesized with the aim of developing new non‐steroidal inhibitors of 17β‐hydroxysteroid dehydrogenase type 2 (17βHSD2) – a novel and attractive target for the treatment of osteoporosis. 17βHSD2 catalyzes the oxidation of the highly active estrogen 17β‐estradiol (E2) and androgen testosterone (T) into the weak estrone and androstenedione, respectively. Inhibition of this enzyme will locally in the bone lead to an increase in E2 and T levels, two key players in the maintenance of the balance between bone resorption and bone formation. In this study, a new class of 17βHSD2 inhibitors with a 1H‐1,2,4‐triazole scaffold was identified; the three best compounds 8b, 8f, and 13a showed moderate 17βHSD2 inhibitory activity and a good selectivity toward 17βHSD1. They could be a useful tool to map the unexplored enzyme active site.
A First‐Principles Study on the Interaction between Alkyl Radicals and Graphene
Authors: Denis Pablo A. , Iribarne Federico
Published: April 2012

The interaction between alkyl radicals and graphene was studied by means of dispersion‐corrected density functional theory. The results indicate that isolated alkyl radicals are not likely to be attached onto perfect graphene. It was found that the covalent binding energies are low, and because of the large entropic contribution, Δ is positive for methyl, ethyl, isopropyl, and tert‐butyl radicals. Although the alkylation may proceed by moderate heating, the desorption barriers are low. For the removal of the methyl and tert‐butyl radicals covalently bonded to graphene, 15.3 and 2.4 kcal mol−1 are needed, respectively. When alkyl radicals are agglomerated, the binding energies are increased. For the addition in the ortho position and on opposite sides of the sheet, the graphene–CH3 binding energy is increased by 20 kcal mol−1, whereas for the para addition on the same side of the sheet, the increment is 9.4 kcal mol−1. In both cases, the agglomeration turns the Δ<0. For the ethyl radical, the ortho addition on opposite sides of the sheet has a negative Δ, whereas for isopropyl and tert‐butyl radicals the reactions are endergonic. The attachment of the four alkyl radicals under consideration onto the zigzag edges is exergonic. The noncovalent adsorption energies computed for ethyl, isopropyl, and tert‐butyl radicals are significantly larger than the graphene–alkyl‐radical covalent binding energies. Thus, physisorption is favored over chemisorption. As for the Δ for the adsorption of isolated alkyl radicals, only the tert‐butyl radical is likely to be exergonic. For the phenalenyl radical we were not able to locate a local minimum for the chemisorbed structure since it moves to the physisorbed structure. An important conclusion of this work is that the consideration of entropic effects is essential to investigate the interaction between graphene and free radicals.
Current status of functional imaging in eating disorders
Authors: Frank Guido K.W. , Kaye Walter H.
Published: April 2012

Eating Disorders are complex psychiatric problems that involve biologic and psychological factors. Brain imaging studies provide insights about how functionally connected brain networks may contribute to disturbed eating behavior, resulting in food refusal and altered body weight, but also body preoccupations and heightened anxiety. In this article, we review the current state of brain imaging in eating disorders, and how such techniques may help identify pathways that could be important in the treatment of those often detrimental disorders. © 2012 by Wiley Periodicals, Inc. (Int J Eat Disord 2012; 45:723–736)
The impact of subterranean termite activity on water infiltration and topsoil properties in Burkina Faso
Authors: Mettrop I. S. , Cammeraat L. H. , Verbeeten E.
Published: April 2012

Few quantitative experimental studies have been carried out on the influence of subterranean termite activity on the water infiltration capacity of crusted soils in the semi‐arid Sahelian region. These studies found increased infiltration rates on soils that were affected by foraging galleries of subterranean termites. In this paper, remarkable results are presented from crusted agricultural fields in the Sanmatenga region in Burkina Faso with clear termite activity compared to reference fields without termite activity. Fine‐scale rainfall experiments were carried out and general topsoil (upper 5 cm) characteristics were measured. Infiltration rates were found to be significantly slower on plots affected by subterranean termite activity. These results are contradictory to the findings reported in general literature. On the basis of topsoil property measurements, the reduced infiltration rates cannot be indisputably explained, and we suggest that the main responsible factor for a reduction of infiltration was related to differences in topsoil surface (upper 3 mm) properties. Two hypotheses are formulated in an attempt to explain the reduced water infiltration rates on termite plots. Copyright © 2012 John Wiley & Sons, Ltd.
Pituitary adenylate cyclase‐activating peptide and vasoactive intestinal polypeptide bias Langerhans cell Ag presentation toward Th17 cells
Authors: Ding Wanhong , Manni Michela , Stohl Lori L. , Zhou Xi K. , Wagner John A. , Granstein Richard D.
Published: April 2012

Epidermal Langerhans cells (LCs) are dendritic APCs that play an important role in cutaneous immune responses. LCs are associated with epidermal nerves and the neuropeptides vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase‐activating polypeptide (PACAP) inhibit LC Ag presentation for Th1‐type immune responses. Here, we examined whether PACAP or VIP modulates LC Ag presentation for induction of IL‐17A‐producing CD4+ T cells. Treatment with VIP or PACAP prior to in vitro LC Ag presentation to CD4+ T cells enhanced IL‐17A, IL‐6, and IL‐4 production, decreased interferon (IFN)‐γ and interleukin (IL)‐22 release, and increased RORγt and Gata3 mRNA expression while decreasing T‐bet expression. The CD4+ T‐cell population was increased in IL‐17A‐ and IL‐4‐expressing cells and decreased in IFN‐γ‐expressing cells. Addition of anti‐IL‐6 mAb blocked the enhanced IL‐17A production seen with LC preexposure to VIP or PACAP. Intradermal administration of VIP or PACAP prior to application of a contact sensitizer at the injection site, followed by harvesting of draining lymph node CD4+ T cells and stimulation with anti‐CD3/anti‐CD28 mAbs, enhanced IL‐17A and IL‐4 production but reduced production of IL‐22 and IFN‐γ. PACAP and VIP are endogenous mediators that likely regulate immunity and immune‐mediated diseases within the skin.
Complement regulates conventional DC‐mediated NK‐cell activation by inducing TGF‐β1 in Gr‐1+ myeloid cells
Authors: Qing Xiaoping , Koo Gloria C. , Salmon Jane E.
Published: April 2012

Complement activation modulates DC‐mediated T‐cell activation, but whether complement affects DC‐mediated priming of NK cells is unknown. Here, we demonstrated that conventional DCs (cDCs) from C3−/− and C5aR−/− mice are hyperresponsive to polyI:C, a TLR3 ligand, leading to enhanced NK‐cell activation. We found that cDCs lack C5a receptor (C5aR) and do not respond to C5a directly. Depletion of Gr‐1+ myeloid cells augments polyI:C‐induced cDC activation in WT but not in C3−/− or C5aR−/− mice, indicating that the effect of complement activation on cDCs is indirectly mediated through C5aR‐expressing Gr‐1+ myeloid cells. We further demonstrated that the mechanism by which Gr‐1+ myeloid cells regulate the activity of cDCs involves C5a‐dependent TGF‐β1 production in Gr‐1+ myeloid cells. C5a enhances and blocking C5aR decreases TGF‐β1 production in cultured bone marrow Gr‐1+CD11b+ cells. C5aR deficiency is associated with reduced circulating TGF‐β1 levels, while depleting Gr‐1+ myeloid cells abrogates this difference between WT and C5aR−/− mice. Lastly, we showed that enhanced cDC–NK‐cell activity in C3−/− mice led to delayed melanoma tumor growth. Thus, complement activation indirectly regulates cDC–NK‐cell activation in response to inflammatory stimuli such as TLR3 by promoting TGF‐β1 production in Gr‐1+ myeloid cells at steady state.
Spatial distribution of pipe collapses in Goodwin Creek Watershed, Mississippi
Authors: Zhang T. , Wilson G. V.
Published: April 2012

The internal erosion of soil pipes can induce pipe collapses that affect soil erosion processes and landform evolution. The objective of this study was to determine the spatial distribution of pipe collapses in agricultural fields of Goodwin Creek watershed. Ground survey was carried out to detect pipe collapses, and the location, size and surface elevation was measured with differential GPS. A total of 143 of the 145 pipe collapses were found in cropland, and the density was approximately 0.58 collapses per hectare. The spatial distribution of pipe collapses was not uniform as pipe collapses were concentrated in the flat alluvial plains where the land use was dominated by cropland. One of the four parcels had 90% of the pipe collapses with a density of 7.7 collapses per hectare. The mean depth, area and volume of these pipe collapses were 0.12 m, 0.34 m2 and 0.02 m3, respectively, and all these properties exhibited a skewed distribution. The drainage area–slope gradient equation, which has been widely used for erosion phenomenon prediction, did not represent pipe collapses in this study as the coefficient of determination was <0.01. This is clear evidence that subsurface flow is not represented by surface topographic characteristics. The pipe collapses were found to intercept runoff, thereby reducing the slope length factor by 6% and the drainage area by 7%. Both of these factors can reduce the sheet and rill erosion; however, the increased subsurface flow could enhance ephemeral gully erosion. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Factors controlling diurnal variation in the isotopic composition of atmospheric water vapour observed in the taiga, eastern Siberia
Authors: Ueta Akihiro , Sugimoto Atsuko , Iijima Yoshihiro , Yabuki Hironori , Maximov Trofim C. , Velivetskaya Tatiana A. , Ignatiev Alexander V.
Published: April 2012

Deciduous forest covers vast areas of permafrost under severe dry climate in eastern Siberia. Understanding the water cycle in this forest ecosystem is quite important for climate projection. In this study, diurnal variations in isotopic compositions of atmospheric water vapour were observed in eastern Siberia with isotope analyses of precipitation, sap water of larch trees, soil water, and water in surface organic layer during the late summer periods of 2006, 2007, and 2008. In these years, the soil moisture content was considerably high due to unusually large amounts of summer rainfall and winter snowfall. The observed sap water δ18O ranged from −17.9‰ to −13.3‰, which was close to that of summer precipitation and soil water in the shallow layer, and represents that of transpired water vapour. On sunny days, as the air temperature and mixing ratio rose from predawn to morning, the atmospheric water vapour δ18O increased by 1‰ to 5‰ and then decreased by about 2‰ from morning to afternoon with the mixing ratio. On cloudy days, by contrast, the afternoon decrease in δ18O and the mixing ratio was not observed. These results show that water vapour that transpired from plants, with higher δ18O than the atmospheric water vapour, contributes to the increase in δ18O in the morning, whereas water vapour in the free atmosphere, with lower δ18O, contributes to the decrease in the afternoon on sunny days. The observed results reveal the significance of transpired water vapour, with relatively high δ18O, in the water cycle on a short diurnal time scale and confirm the importance of the recycling of precipitation through transpiration in continental forest environments such as the eastern Siberian taiga. Copyright © 2012 John Wiley & Sons, Ltd.
Influence of basin characteristics on baseflow and stormflow chemistry in the Great Smoky Mountains National Park, USA
Authors: Neff Keil J. , Schwartz John S. , Moore Stephen E. , Kulp Matt A.
Published: April 2012

Relationships between stream chemistry and elevation, area, Anakeesta geology, soil properties, and dominant vegetation were evaluated to identify the influence of basin characteristics on baseflow and stormflow chemistry in eight streams of the Great Smoky Mountains National Park. Statistical analyses were employed to determine differences between baseflow and stormflow chemistry, and relate basin‐scale factors governing local chemical processes to stream chemistry. Following precipitation events, stream pH was reduced and aluminium concentrations increased, while the response of acid neutralizing capacity (ANC), nitrate, sulfate, and base cations varied. Several basin characteristics were highly correlated with each other, demonstrating the interrelatedness of topographical, geological, soil, and vegetative parameters. These interrelated basin factors uniquely influenced acidification response in these streams. Streams in higher‐elevation basins (>975 m) had significantly lower pH, ANC, sodium, and silicon and higher nitrate concentrations (p < 0.05). Streams in smaller basins (<10 km2) had significantly lower nitrate, sodium, magnesium, silicon, and base cation concentrations. In stormflow, streams in basins with Anakeesta geology (>10%) had significantly lower pH and sodium concentrations, and higher aluminium concentrations. Chemical and physical soil characteristics and dominant overstory vegetation in basins were more strongly correlated with baseflow and stormflow chemical constituents than topographical and geological basin factors. Saturated hydraulic conductivity, of all the soil parameters, was most related to concentrations of stormflow constituents. Basins with higher average hydraulic conductivities were associated with lower stream pH, ANC, and base cation concentrations, and higher nitrate and sulfate concentrations. These results emphasize the importance of soil and geological properties influencing stream chemistry and promote the prioritization of management strategies for aquatic resources. Copyright © 2012 John Wiley & Sons, Ltd.
Are increased carotid artery pulsatility and resistance indexes early signs of vascular abnormalities in young obese males?
Authors: Ozari H. Onur , Oktenli Cagatay , Celik Serkan , Tangi Fatih , Ipcioglu Osman , Terekeci Hakan M. , Top Cihan , Uzun Mehmet , Sanisoglu Yavuz S. , Nalbant Selim
Published: April 2012

Purpose:

To provide insight into the factors by which obesity in itself may directly lead to early arterial damage, we aimed to determine early sonographic markers of obesity‐related vascular dysfunction in young obese males.

Methods:

Thirty‐five young obese males and 23 age‐matched healthy male volunteers were recruited into the study. Common carotid artery pulsatility index and resistance index were calculated from blood flow velocities curves obtained by pulsed Doppler ultrasonography.

Results:

The mean pulsatility index, resistance index, body mass index, waist circumference, systolic and diastolic blood pressure, homeostasis model assessment for insulin resistance, plasma fasting glucose, insulin, C‐peptide, triglycerides, low‐density lipoprotein cholesterol, and high‐sensitivity C‐reactive protein were statistically higher in obese subjects than in healthy controls.

Conclusions:

Our results suggest that depressed vessel compliance and increased vascular resistance are features of young, obese, normotensive subjects independently of and in addition to cardiovascular risk factors. As changes in arterial wall properties may be incipient in young obese subjects, future studies will be required to demonstrate whether early intervention such as diet and exercise in this population can improve vascular functions. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012© 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012
The Ford Foundation and the Rise of Behavioralism in Political Science
Authors: HAUPTMANN EMILY
Published: April 2012

How did behavioralism, one of the most influential approaches to the academic study of politics in the twentieth century, become so prominent so quickly? I argue that many political scientists have either understated or ignored how the Ford Foundation's Behavioral Sciences Program gave form to behavioralism, accelerated its rise, and helped root it in political science. I then draw on archived documents from Ford as well as one of its major grantees, U. C. Berkeley, to present several examples of how Ford used its funds to encourage the behavioral approach at a time when it had few adherents among political scientists.
4D blood flow visualization fusing 3D and 4D MRA image sequences
Authors: Forkert Nils Daniel , Fiehler Jens , Illies Till , Möller Dietmar P.F. , Handels Heinz , Säring Dennis
Published: April 2012

Purpose:

To present and evaluate the feasibility of a novel automatic method for generating 4D blood flow visualizations fusing high spatial resolution 3D and time‐resolved (4D) magnetic resonance angiography (MRA) datasets.

Materials and Methods:

In a first step, the cerebrovascular system is segmented in the 3D MRA dataset and a surface model is computed. The hemodynamic information is extracted from the 4D MRA dataset and transferred to the surface model using rigid registration where it can be visualized color‐coded or dynamically over time. The presented method was evaluated using software phantoms and 20 clinical datasets from patients with an arteriovenous malformation. Clinical evaluation was performed by comparison of Spetzler–Martin scores determined from the 4D blood flow visualizations and corresponding digital subtraction angiographies.

Results:

The performed software phantom validation showed that the presented method is capable of producing reliable visualization results for vessels with a minimum diameter of 2 mm for which a mean temporal error of 0.27 seconds was achieved. The clinical evaluation based on 20 datasets comparing the 4D visualization to DSA images revealed an excellent interrater reliability.

Conclusion:

The presented method enables an improved combined representation of blood flow and anatomy while reducing the time needed for clinical rating. J. Magn. Reson. Imaging 2012;36:443–453. © 2012 Wiley Periodicals, Inc.
In vivo NIRF Imaging of Tumor Targetability of Nanosized Liposomes in Tumor‐Bearing Mice
Authors: Lee Sangmin , Lee Seung‐Young , Park Sangjin , Ryu Ju Hee , Na Jin Hee , Koo Heebeom , Lee Kyung Eun , Jeon Hyesung , Kwon Ick Chan , Kim Kwangmeyung , Jeong Seo Young
Published: April 2012

To optimize tumor targetability of nanosized liposomes for application as drug carriers, various liposomes are prepared by incorporating different amounts (10, 30, and 50 wt%) of cationic, anionic, and PEGylated lipids into neutral lipid. In vivo near‐infrared fluorescence images reveal that PEG‐PE/PC liposomes display high tumor accumulation in tumor‐bearing mice, while large amounts of DOTAP/PC liposomes are rapidly captured in the liver, resulting in poor tumor accumulation. These results demonstrate that optimization of the surface properties of liposomes is very important for their tumor targetability, and that in vivo imaging techniques are useful in developing and optimizing nanosized liposome‐based drug carriers.

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Amino‐Functionalized Cellulose Nanoparticles: Preparation, Characterization, and Interactions with Living Cells
Authors: Nikolajski Melanie , Wotschadlo Jana , Clement Joachim H. , Heinze Thomas
Published: April 2012

Spherical nanoparticles with sizes from 80 to 200 nm are obtained by self‐assembly of highly functionalized 6‐deoxy‐6‐(ω‐aminoalkyl)aminocellulosecarbamates. The particles are very stable, nontoxic, and possess primary amino groups that are accessible to further modifications in aqueous suspension. The particles can be labeled with rhodamine B isothiocyanate without changing their size, stability, and shape. The nanoparticles obtained are investigated by means of photo correlation spectroscopy, zeta potential measurements, SEM and fluorescence spectroscopy. Incorporation of the nanoparticles in human foreskin fibroblasts BJ‐1‐htert and breast carcinoma MCF‐7 cells without any transfection reagent is proved by means of confocal laser scanning microscopy.

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On Vaught’s Conjecture and finitely valued MV algebras
Authors: Nola Antonio Di , Lenzi Giacomo
Published: April 2012

We show that the complete first order theory of an MV algebra has \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$2^{\aleph _0}$\end{document} countable models unless the MV algebra is finitely valued. So, Vaught's Conjecture holds for all MV algebras except, possibly, for finitely valued ones. Additionally, we show that the complete theories of finitely valued MV algebras are \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$2^{\aleph _0}$\end{document} and that all ω‐categorical complete theories of MV algebras are finitely axiomatizable and decidable. As a final result we prove that the free algebra on countably many generators of any locally finite variety of MV algebras is ω‐categorical.
Free‐decomposability in varieties of semi‐Heyting algebras
Authors: Abad Manuel , Cornejo Juan Manuel , Varela Patricio Díaz
Published: April 2012

In this paper we prove that the free algebras in a subvariety \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal V$\end{document} of the variety \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {SH}$\end{document} of semi‐Heyting algebras are directly decomposable if and only if \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal V$\end{document} satisfies the Stone identity.
Mesh independent analysis of shell‐like structures
Authors: Kumar Ashok V. , Periyasamy Premdheepak S.
Published: April 2012

Mesh independent analysis is motivated by the desire to use accurate geometric models represented as equations rather than approximated by a mesh. The trial and test functions are approximated or interpolated on a background mesh that is independent of the geometry. This background mesh is easy to generate because it does not have to conform to the geometry. Essential boundary conditions can be applied using the implicit boundary method where the trial and test functions are constructed utilizing approximate step functions such that the boundary conditions are guaranteed to be satisfied. This approach has been demonstrated for two‐dimensional (2D) and three‐dimensional (3D) structural analysis and is extended in this paper to model shell‐like structures. The background mesh consists of 3D elements that use uniform B‐spline approximations, and the shell geometry is assumed to be defined as parametric surfaces to allow arbitrarily complex shell‐like structures to be modeled. Several benchmark problems are used to study the validity of these 3D B‐spline shell elements. Copyright © 2012 John Wiley & Sons, Ltd.
Discrimination of ischemic and hemorrhagic strokes using a multiplexed, mass spectrometry‐based assay for serum apolipoproteins coupled to multi‐marker ROC algorithm
Authors: Lopez Mary F. , Sarracino David A. , Prakash Amol , Athanas Michael , Krastins Bryan , Rezai Taha , Sutton Jennifer N. , Peterman Scott , Gvozdyak Oksana , Chou Sherry , Lo Eng , Buonanno Ferdinand , Ning MingMing
Published: April 2012

Purpose

Typically, apolipoproteins are individually measured in blood by immunoassay. In this report, we describe the development of a multiplexed selected reaction monitoring (SRM) based assay for a panel of apolipoproteins and its application to a clinical cohort of samples derived from acute stroke patients.

Experimental Design

An SRM assay for a panel of nine apolipoproteins was developed on a triple quadrupole mass spectrometer. Quantitative data for each apolipoprotein were analyzed to determine expression ratio and receiver operating characteristic (ROC) values for ischemic versus hemorrhagic stroke.

Results

The optimized SRM assay was used to interrogate a small cohort of well‐characterized plasma samples obtained from patients with acute ischemic and hemorrhagic strokes. The ROC analyses demonstrated good classification power for several single apolipoproteins, most notably apoC‐III and apoC‐I. When a novel multi‐marker ROC algorithm was applied, the ischemic versus hemorrhagic groups were best differentiated by a combination of apoC‐III and apoA‐I with an area under the curve (AUC) value of 0.92.

Conclusions and clinical relevance

This proof‐of‐concept study provides interesting and provocative data for distinguishing ischemic versus hemorrhage within first week of symptom onset. However, the observations are based on one cohort of patient samples and further confirmation will be required.
Effect of Water Extracts from Edible Myrtaceae Plants on Uptake of 2‐(n‐(7‐nitrobenz‐2‐oxa‐1,3‐diazol‐4‐yl)amino)‐2‐deoxyglucose in TNF‐α‐Treated FL83B Mouse Hepatocytes
Authors: Chang Wen‐Chang , Shen Szu‐Chuan
Published: April 2012

This study investigated the glucose uptake activity of the water extracts from the leaves and fruit of edible Myrtaceae plants, including guava (Psidium guajava Linn.), wax apples [Syzygium samarangense (Blume) Merr. and L.M. Perry], Pu‐Tau [Syzygium jambo (L.) Alston], and Kan‐Shi Pu‐Tau (Syzygium cumini Linn.) in FL83B mouse hepatocytes. The fluorescent dye 2‐(n‐(7‐nitrobenz‐2‐oxa‐1,3‐diazol‐4‐yl)amino)‐2‐deoxyglucose was used to estimate the uptake ability of the cells. Glucose uptake test showed that pink wax apple fruit extract (PWFE) exhibits the highest glucose uptake activity, at an increment of 21% in the insulin‐resistant FL83B mouse hepatocytes as compared with the TNF‐α‐treated control group. Vescalagin was isolated using column chromatography of PWFE. This compound, at the concentration of 6.25 µg/mL, exhibits the same glucose uptake improvement in insulin‐resistant cells as PWFE at a 100‐µg/mL dose. We postulate that vescalagin is an active component in PWFE that may alleviate the insulin resistance in mouse hepatocytes. Copyright © 2012 John Wiley & Sons, Ltd.
XPS composition study of stacked Si oxide/Si nitride/Si oxide nano‐layers
Authors: Ravizza E. , Spadoni S. , Piagge R. , Comite P. , Wiemer C.
Published: April 2012

X‐ray Photoelectron Spectroscopy (XPS) was used to investigate the silicon nitride composition in stacked Si oxide/Si nitride/Si oxide nano‐layers. The standard approach for stoichiometry estimation, valid for homogeneous compositions, was corrected for the case of very small thickness and thin overlayer. Copyright © 2012 John Wiley & Sons, Ltd.
A statistical interpretation of molecular delta layer depth profiles
Authors: Wucher A. , Krantzman K.D. , Lu C. , Winograd N.
Published: April 2012

The delta layer depth response predicted by a simple statistical sputtering model is compared with molecular sputter depth profile data obtained on Langmuir–Blodgett delta layer systems. All input parameters of the statistical sputtering model are determined from low‐fluence molecular dynamics simulations performed for 20‐keV C60 cluster bombardment of silicon, making the model de facto parameter free. It is found that both calculated and measured depth response functions can be parametrised by the semiempirical Dowsett expression. The resulting parameters (leading and trailing edge slope, full‐width at half‐maximum) agree surprisingly well with those determined from the measured depth profiles. Copyright © 2012 John Wiley & Sons, Ltd.
Signals of secondary ions and resonantly and nonresonantly ionized neutrals sputtered from binary alloys as a function of oxygen exposure
Authors: München J. , Lipinsky D. , Arlinghaus H. F.
Published: April 2012

For the quantification of elements in different chemical matrices, in‐depth knowledge of the emission processes of atomic and molecular particles under ion bombardment is of great importance. This knowledge can be obtained by analyzing the flux composition of secondary ions and neutrals under ion bombardment. Flux composition, the mutual interaction of alloy components, and the relative sensitivity factors as a function of oxygen exposure and as a function of different redox potentials between alloy components were investigated. GdTi80 (20 at% Gd and 80 at% Ti), GdFe75, TiFe50, and TiCu50 binary alloys were used for the experiments. The data show that the mutual interaction of alloy components during oxygen exposure causes significant changes in the secondary ion and neutral yield. Also, significant differences between the relative sensitivity factors for postionized atoms sputtered from binary alloys as a function of oxygen exposure were observed. Measurements using time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and resonant and nonresonant laser‐secondary neutral mass spectrometry (laser‐SNMS) show that the fluctuation of the yield ratios can be explained by strong variations in the secondary ion yield and by variations of the molecular and atomic fractions in the flux composition of secondary particles. Copyright © 2012 John Wiley & Sons, Ltd.
A multivariate meta‐analysis approach for reducing the impact of outcome reporting bias in systematic reviews
Authors: Kirkham Jamie J. , Riley Richard D. , Williamson Paula R.
Published: April 2012

Multivariate meta‐analysis allows the joint synthesis of multiple correlated outcomes from randomised trials, and is an alternative to a separate univariate meta‐analysis of each outcome independently. Usually not all trials report all outcomes; furthermore, outcome reporting bias (ORB) within trials, where an outcome is measured and analysed but not reported on the basis of the results, may cause a biased set of the evidence to be available for some outcomes, potentially affecting the significance and direction of meta‐analysis results. The multivariate approach, however, allows one to ‘borrow strength’ across correlated outcomes, to potentially reduce the impact of ORB. Assuming ORB missing data mechanisms, we aim to investigate the magnitude of bias in the pooled treatment effect estimates for multiple outcomes using univariate meta‐analysis, and to determine whether the ‘borrowing of strength’ from multivariate meta‐analysis can reduce the impact of ORB. A simulation study was conducted for a bivariate fixed effect meta‐analysis of two correlated outcomes. The approach is illustrated by application to a Cochrane systematic review. Results show that the ‘borrowing of strength’ from a multivariate meta‐analysis can reduce the impact of ORB on the pooled treatment effect estimates. We also examine the use of the Pearson correlation as a novel approach for dealing with missing within‐study correlations, and provide an extension to bivariate random‐effects models that reduce ORB in the presence of heterogeneity. Copyright © 2012 John Wiley & Sons, Ltd.
Incomplete state building – incomplete democracy? How to interpret internal political development in the post-Soviet de facto states. Conclusion.
Authors: von Steinsdorff Silvia
Published: April 2012

The empirical case studies of this special issue not only provide an illuminating insight into the dynamic of political processes within the post-Soviet de facto states, they also contribute to the discussion of possible links between different strategies of state-building and the success or failure of democratization. Summing up the main findings of the issue, this article carves out the similarities and the differences in the internal political trajectories of the non-recognized but quite stable entities under analysis. Despite sometimes contradicting empirical evidence, one central outcome is clear: the established theoretical assumption that uncontested external sovereignty is a necessary precondition for internal democratization needs to be reconsidered.
Establishment of an Endangered species on a private nature refuge: what can we learn from reintroductions of the bridled nailtail wallaby Onychogalea fraenata?
Authors: Kingsley Lisa , Goldizen Anne , Fisher Diana O.
Published: April 2012

Translocation and reintroduction are used to reduce extinction risk associated with a small population and range size in threatened mammal species. We evaluated the outcome of a reintroduction of the bridled nailtail wallaby Onychogalea fraenata to Avocet Nature Refuge, a private refuge in central Queensland, Australia. This macropod was also reintroduced to Idalia National Park in western Queensland in 1996 and occurs in one natural population in central Queensland. We estimated population growth, adult and juvenile survival, and distribution changes since the last release of O. fraenata to Avocet in 2005, and evaluated female reproductive success and health. Although animals were in good condition, population size was a tenth of that of the 1996 Idalia reintroduction reported after 3 years and, unlike at Idalia, juvenile survival at Avocet was low. The likely causes are consistent with predictors of translocation and reintroduction failures in mammals. These are predation, the small number of individuals in each release, the likely suboptimal health status of reintroduced individuals, drought, and possibly lack of dispersal from the small area of preferred habitat. The lessons of this reintroduction are that future attempts are likely to have the best chance of success if they occur in non-drought years, at sites with large, non-fragmented areas of brigalow forest, involve the release of large groups of animals together, and are accompanied by intensive, long-term baiting to control introduced predators.
Extending relational algebra with similarities
Authors: HAJDINJAK MELITA , BIERMAN GAVIN
Published: April 2012

In this paper we propose various extensions to the relational model to support similarity-based querying. We build upon the-relation model, where tuples are assigned values from an arbitrary semiring, and its associated positive relational algebra$\text{RA}^{+}_{\mathcal{K}}$. We consider a recently proposed extension to$\text{RA}^{+}_{\mathcal{K}}$using a monus operation on the semiring to support negative queries, and show how, surprisingly, it fails for important ‘fuzzy’ semirings. Instead, we suggest using a negation operator. We also consider the identities satisfied by the relational algebra$\text{RA}^{+}_{\mathcal{K}}$. We show that moving from a semiring to a particular form of lattice (a De Morgan frame) yields a relational algebra that satisfies all the classical (positive) relational algebra identities. We claim that to support real-world similarity queries realistically, one must move from tuple-level annotations to attribute-level annotations. We show in detail how our De Morgan frame-based model can be extended to support attribute-level annotations and give worked examples of similarity queries in this setting.
INFINITUDE OF ELLIPTIC CARMICHAEL NUMBERS
Authors: EKSTROM AARON , POMERANCE CARL , THAKUR DINESH S.
Published: April 2012

In 1987, Gordon gave an integer primality condition similar to the familiar test based on Fermat’s little theorem, but based instead on the arithmetic of elliptic curves with complex multiplication. We prove the existence of infinitely many composite numbers simultaneously passing all elliptic curve primality tests assuming a weak form of a standard conjecture on the bound on the least prime in (special) arithmetic progressions. Our results are somewhat more general than both the 1999 dissertation of the first author (written under the direction of the third author) and a 2010 paper on Carmichael numbers in a residue class written by Banks and the second author.
A Transformation-based implementation for CLP with qualification and proximity
Authors: CABALLERO R. , RODRÍGUEZ-ARTALEJO M. , ROMERO-DÍAZ C. A.
Published: April 2012

Uncertainty in logic programming has been widely investigated in the last decades, leading to multiple extensions of the classical logic programming paradigm. However, few of these are designed as extensions of the well-established and powerful Constraint Logic Programming (CLP) scheme for CLP. In a previous work we have proposed the proximity-based qualified constraint logic programming (SQCLP) scheme as a quite expressive extension of CLP with support for qualification values and proximity relations as generalizations of uncertainty values and similarity relations, respectively. In this paper we provide a transformation technique for transforming SQCLP programs and goals into semantically equivalent CLP programs and goals, and a practical Prolog-based implementation of some particularly useful instances of the SQCLP scheme. We also illustrate, by showing some simple – and working – examples, how the prototype can be effectively used as a tool for solving problems where qualification values and proximity relations play a key role. Intended use of SQCLP includes flexible information retrieval applications.
A mechanistic ecohydrological model to investigate complex interactions in cold and warm water‐controlled environments: 2. Spatiotemporal analyses
Authors: Fatichi S. , Ivanov V. Y. , Caporali E.
Published: April 2012

An ecohydrological model Tethys‐Chloris (T&C) described in the companion paper is applied to two semiarid systems characterized by different climate and vegetation cover conditions. The Lucky Hills watershed in Arizona represents a typical small, “unit‐source” catchment of a desert shrub system of the U.S. southwest. Two nested basins of the Reynolds Creek Experimental watershed (Idaho, U.S.A.), the Reynolds Creek Mountain East and Tollgate catchments, are representative of a semiarid cold climate with seasonal snow cover. Both exhibit a highly non‐uniform vegetation cover. A range of ecohydrological metrics of the long‐term model performance is presented to highlight the model capabilities in reproducing hydrological and vegetation dynamics both at the plot and the watershed scales. A diverse set of observations is used to confirm the simulated dynamics. Highly satisfactory results are obtained without significant (or any) calibration efforts despite the large phase‐space dimensionality of the model, the uncertainty of imposed boundary conditions, and limited data availability. It is argued that a significant investment into the model design based on the description of physical, biophysical, and ecological processes leads to such a consistent simulation skill. The simulated patterns mimic the outcome of hydrological and vegetation dynamics with high realism, as confirmed from spatially distributed remote sensing data. Further community efforts are warranted to address the issue of thorough quantitative assessment. The current lack of appropriate data hampers the development and testing of process‐based ecohydrological models. It is further argued that the mechanistic nature of the T&C model can be valuable for designing virtual experiments and developing questions of scientific inquiry at a range of spatiotemporal scales.
Reduced order parameter estimation using quasilinearization and quadratic programming
Authors: Siade Adam J. , Putti Mario , Yeh William W.‐G.
Published: April 2012

The ability of a particular model to accurately predict how a system responds to forcing is predicated on various model parameters that must be appropriately identified. There are many algorithms whose purpose is to solve this inverse problem, which is often computationally intensive. In this study, we propose a new algorithm that significantly reduces the computational burden associated with parameter identification. The algorithm is an extension of the quasilinearization approach where the governing system of differential equations is linearized with respect to the parameters. The resulting inverse problem therefore becomes a linear regression or quadratic programming problem (QP) for minimizing the sum of squared residuals; the solution becomes an update on the parameter set. This process of linearization and regression is repeated until convergence takes place. This algorithm has not received much attention, as the QPs can become quite large, often infeasible for real‐world systems. To alleviate this drawback, proper orthogonal decomposition is applied to reduce the size of the linearized model, thereby reducing the computational burden of solving each QP. In fact, this study shows that the snapshots need only be calculated once at the very beginning of the algorithm, after which no further calculations of the reduced‐model subspace are required. The proposed algorithm therefore only requires one linearized full‐model run per parameter at the first iteration followed by a series of reduced‐order QPs. The method is applied to a groundwater model with about 30,000 computation nodes where as many as 15 zones of hydraulic conductivity are estimated.