bluuebunny/crossref_metadata_2025 huggingface dataset:
Response of a red clone of Myzus persicae (Hemiptera: Aphididae) to sublethal concentrations of imidacloprid in the laboratory and greenhouse
Authors: Janmaat Alida , Borrow Erin , Matteoni Jim , Jones Gary
Published: February 2011

BACKGROUND: Pest resurgence following a pesticide application may occur owing to a stimulatory (hormetic) response to sublethal insecticide concentrations. The objective of the present study was to examine the potential for a greenhouse‐derived red clone of Myzus persicae to exhibit resurgence owing to a hormetic response following a systemic imidacloprid treatment in a bell pepper greenhouse.

RESULTS: No differences in mortality and fecundity were observed among apterous adults exposed to sublethal imidacloprid concentrations on excised pepper leaves fed aqueous solutions of imidacloprid. Survival of first‐generation progeny was negatively affected by imidacloprid exposure, yet surviving progeny exhibited no differences in development rates or fecundity from progeny of adults unexposed to imidacloprid. Aphid mortality declined most rapidly in clip cages on pepper leaves at the top of the pepper canopy as compared with leaves present at the middle or bottom of the pepper canopy.

CONCLUSION: Imidacloprid decays rapidly in mature pepper plants, resulting in sublethal concentrations in the upper canopy in as little as 4 weeks. Sublethal insecticide concentrations have been implicated in the resurgence of pest populations; however, exposure to sublethal doses of imidacloprid are unlikely to result in pesticide‐induced resurgence of the M. persicae aphid clone examined in this study. Copyright © 2011 Society of Chemical Industry
Ultrafast transient gain in Ge/SiGe quantum wells
Authors: Köster N. S. , Lange C. , Kolata K. , Chatterjee S. , Chrastina D. , Isella G. , von Känel H. , Sigg H. , Schäfer M. , Kira M. , Koch S.W.
Published: February 2011

The ultrafast carrier dynamics of Ge/SiGe quantum wells on Si substrate is investigated by pump‐probe spectroscopy. Spectrally tunable 80 fs pulses emitted by an opto‐parametric amplifier are used to excite the sample and a white‐light supercontinuum generated from a 1 kHz Ti:sapphire regenerative amplifier system is used to probe the sample transmission.

Pronounced nonequilibrium effects are observed in the relaxation dynamics. The pump energy dependence of these effects is discussed. If the sample is excited under close‐to‐resonant pumping conditions, transient gain is observed. The findings are explained using a microscopic many‐body theory. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Controlling the correlations in frequency upconversion in PPLN and PPKTP waveguides
Authors: Brecht Benjamin , Eckstein Andreas , Silberhorn Christine
Published: February 2011

Frequency upconversion can be utilized as flexible broadband mode selector for engineered phase matching properties. We give a detailed spectral analysis of frequency upconversion in two different nonlinear waveguides, namely LiNbO3 and KTiOPO4.

We investigate the spectral correlations between input and output photon and derive conditions for their absence. By applying our analysis to the special scenario of upconverting a 1550 nm input photon, we find that for this scenario LiNbO3 is better suited than KTiOPO4. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background
Authors: Eckstein Andreas , Christ Andreas , Mosley Peter J. , Silberhorn Christine
Published: February 2011

The g(2) correlation function of a light beam depends on its photon statistcs. In quantum optics, this effect can be used to determine the effective mode number of a type II parametric downconversion source.

However, the outcome is very sensitive against background light from other sources. We consider the experimental challenges of this approach and introduce a simple model to account for influence of the background. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hot carrier cooling by acoustic phonons in epitaxial graphene by ultrafast pump‐probe spectroscopy
Authors: Sun Dong , Divin Charles , Berger Claire , de Heer Walt A. , First Phillip N. , Norris Theodore B.
Published: February 2011

We report the application nondegenerate ultrafast mid‐infrared spectroscopy to investigate the acoustic phonon cooling process in epitaxial graphene. We show that the power‐dependent experimental results match theoretical predictions of the low temperature acoustic cooling process. The hot phonon effect in acoustic phonon cooling is observed experimentally, and a deformation potential of 30 eV can be determined from fitting the data. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Si and SixGe1‐x NWs studied by Raman spectroscopy
Authors: Anaya J. , Prieto A. C. , Martínez O. , Torres A. , Martín‐Martín A. , Jiménez J. , Rodríguez A. , Sangrador J. , Rodríguez T.
Published: February 2011

Group IV nanostructures have attracted a great deal of attention because of their potential applications in optoelectronics and nanodevices. Raman spectroscopy has been extensively used to characterize nanostructures since it provides non destructive information about their size, by the adequate modeling of the phonon confinement effect. The Raman spectrum is also sensitive to other factors, as stress and temperature, which can mix with the size effects borrowing the interpretation of the Raman spectrum. We present herein an analysis of the Raman spectra obtained for Si and SiGe nanowires; the influence of the excitation conditions and the heat dissipation media are discussed in order to optimize the experimental conditions for reliable spectra acquisition and interpretation. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Correlation between cathodoluminescent and electrical properties of dislocation network in the space charge region of Schottky‐diode
Authors: Bondarenko Anton , Vyvenko Oleg , Isakov Ivan , Kononchuk Oleg
Published: February 2011

A detailed investigation and comparison of low‐temperature cathodoluminescent (CL) and electrical properties of DN is presented. The correlations between the CL, electron beam induced current (EBIC), and CV measurements using the DC electric bias as a parameter are established and analyzed in the scope of the calculated theoretical model. A new CL measurement technique that is complimentary to conventional space charge region spectroscopy (SCRS) methods such as DLTS and MCTS is proposed and the first experimental results using this new approach are described. Shallow dislocation‐related level Ev+Et=0.1 eV is shown to be responsible for D1 dislocation‐related luminescence line. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of silicon ribbon by the SEM methods
Authors: Brantov Sergey , Feklisova Olga , Yakimov Eugene
Published: February 2011

Investigation of silicon layers grown on carbon foil was carried out using the Electron Backscatter Diffraction (EBSD) and Electron Beam Induced Current (EBIC) methods. The EBSD investigations showed that the surface of silicon ribbon is close to (110) and that most of grain boundaries (GBs) are twin boundaries with the misorientation angle of 60° between the neighbouring grains. The diffusion length in Si ribbon studied was obtained to exceed 35 μm. The EBIC measurements showed that the recombination contrast of dislocations and twin GBs at room temperature is practically absent and only random GBs produced a noticeable contrast. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dispersion of photoluminescence peak positions in asymmetric InAs QD multi quantum well structures
Authors: Casas Espínola J. L. , Torchynska T. V. , Polupan G. , Martínez M. Ojeda
Published: February 2011

The photoluminescence and its temperature dependences have been investigated for InAs quantum dots (QDs) embedded in asymmetric GaAs/InxGa1‐xAs/In0.15Ga0.85As/GaAs quantum wells (DWELL structures) as a function of the In content x (x=0.10‐0.25) in the capping InxGa1‐xAs layer. Photoluminescence (PL) study reveals the red shift of QD ground state peak when x increases from 0.10 to 0.15. The significant degradation of PL intensity is monitored together with a blue shift of PL peaks and PL band broadening when x = 0.20 or 0.25. The fitting procedure has been applied on the base of Varshni analysis to PL peaks. It is shown that all DWELL structures are characterized by the same Varshni parameters that are close, but not equal, to the band gap shrinks with temperature in the bulk InAs. The last fact testifies that in studied DWELL structures the process of In/Ga intermixture between QDs and a capping layer takes place partially. However this process cannot explain the difference in PL peak positions. This difference, apparently, related to the different levels of elastic strain in DWELLs that change non monotonically due to the variation of In concentrations in capping layers. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Elastic stress and emission nonhomogeneity in asymmetric InAs quantum dot in a well structures
Authors: Casas Espínola José L. , Torchynska Tetyana V. , Palacios Gomez Jesús , Gómez Gasga G. , Vivas Hernández Alejandro , Cisneros Tamayo Ricardo
Published: February 2011

Photoluminescence (PL) and X‐ray diffraction (XRD) have been studied in InAs quantum dots (QDs) embedded in asymmetric GaAs/InxGa1‐xAs/In0.15Ga1‐0.15As/GaAs quantum wells (dot‐in‐a‐well, DWELL) with the parameter x=0.10‐0.25. The parameter x increasing in the capping layer is accompanied by the non monotonous variation of InAs QD parameters. The PL intensity increases and the PL peak shifts to low energy in structures with x=0.15. On the contrary the structures with x=0.20 and 0.25 are characterized by lower PL intensities and PL peak positions shifted to higher energy. The method of X‐ray diffraction has been applied with the aim to study the variation of elastic strain in asymmetric DWELL structures. It was shown that the minimum of elastic strain corresponds to DWELL with x=0.15. In DWELLs with x=0.20 and 0.25 the level of compressive strain increases. The reasons of strain variation are discussed as well. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nucleation in the Karlsruhe plume during the COPS/TRACKS‐Lagrange experiment
Authors: Junkermann W. , Hagemann R. , Vogel B.
Published: February 2011

A plume of ultrafine particles was observed downwind of the Karlsruhe city and industrial area during the COPS/TRACKS Lagrangian airborne experiment in summer 2007. These ultrafine particles were identified as nucleation‐generated aerosols from emissions of a coal‐fired power plant and an adjacent refinery, the two main emitters of sulphur dioxide in the area. Modelling the production and growth of aerosols with the COSMO‐ART model required, in agreement with the known emission sources, a strong elevated source of sulphur dioxide to explain the temporal evolution of the particle plume. The power plant at Karlsruhe Rheinhafen emits from a 233 m high chimney. The ultrafine particles produced from these fossil‐fuel‐related sources were the dominant fraction of all ultrafine particles in the rural area of the Kraichgau downwind of Karlsruhe, exceeding all other anthropogenic sources and are suspected of being the major contribution to the number of cloud condensation nuclei (CCN) on a regional scale. Compared to previous investigations on the sulphur chemistry in power‐plant plumes, emissions from this power plant, which is equipped with modern stack‐gas cleaning technology, had a higher yield of nucleation‐mode aerosols as CCN precursors per emitted sulphur dioxide mass. Copyright © 2011 Royal Meteorological Society
Influence of the wind profile on the initiation of convection in mountainous terrain
Authors: Hagen Martin , van Baelen Joël , Richard Evelyne
Published: February 2011

A number of days with small precipitating convective cells were investigated using weather radars during the COPS (Convective and Orographically‐induced Precipitation Study) field campaign in the region of the Vosges and the Rhine Valley in Central Europe. Depending on the weather situation, two distinct mechanisms could be identified for the initiation of convection. On some days, cells were initiated over the ridge of the Vosges, whereas on other days cells were initiated in the lee of the Vosges. The initiation of convection appeared to be concentrated in a few favourable locations. Using the Froude number, it was possible to describe the two distinct mechanisms. When the Froude number was low, the flow was diverted around the Vosges and thermally driven convergence at the ridge initiated convection, whereas when the Froude number was high, the flow passed through mountain gaps and then converged on the lee side with the flow in the Rhine Valley. The convergence on the lee side was enhanced at locations where the outflows through valleys converged. Low Froude numbers were accompanied by weak winds varying with height, whereas high Froude numbers were observed during situations with stronger southwesterly winds increasing with height. Copyright © 2011 Royal Meteorological Society
On the relationship between water vapour field evolution and the life cycle of precipitation systems
Authors: Van Baelen J. , Reverdy M. , Tridon F. , Labbouz L. , Dick G. , Bender M. , Hagen M.
Published: February 2011

In this work, we investigate the relationship between the structure and evolution (from initiation to decay) of precipitation systems, and the associated water vapour distributions during the COPS (Convective Orographically‐induced Precipitation Study). This international field campaign took place over an area from the Vosges to the Black Forest Mountains, across the Rhine Valley, in summer 2007. In particular, we consider water vapour retrieval through GPS integrated water vapour 2D maps and 3D tomography, and compare these to precipitation systems observed with the ground‐based C‐band POLDIRAD weather radar.

We have demonstrated the predominant role of water vapour as a precursor to convective initiation for local convective cell generation. Water vapour accumulation on the crest of the orography is associated with ridge convection, while water vapour passing over the mountain top and creating valley outflows generates lee‐side convection, often triggered by a small hill positioned within or close to the valley exit, or by a local convergence with the water vapour field over the plain.

We have also noted that frontal systems seem to develop preferentially where the largest amount of water vapour is available. Likewise, in the case of frontal systems, well‐formed synoptic‐scale storms are associated with high water vapour signatures, while weaker systems with embedded convection appear to trail high water vapour areas where the convective element is associated with local water vapour depletion. This latter aspect could be the signature of convective cloud formation, when water vapour is transferred into liquid water, before the onset of precipitation. Copyright © 2011 Royal Meteorological Society
Characterization of metabolism of (+)‐praeruptorin B and (+)‐praeruptorin E in human and rat liver microsomes by liquid chromatography coupled with ion trap mass spectrometry and time‐of‐flight mass spectrometry
Authors: Song Yue‐Lin , Yan Ru , Jing Wang‐Hui , Zhao Hai‐Yu , Wang Yi‐Tao
Published: February 2011

Peucedani Radix is a Chinese medicinal herb noted for its effects on treatments of respiratory and pulmonary disorders. As a part of a systematic pharmacokinetic evaluation of the herb in our laboratory, the present study investigated, for the first time, the metabolic profile of (+)‐praeruptorin B (dPB) and (+)‐praeruptorin E (dPE), two main bioactive constituents of Peucedani Radix in pooled liver microsomes of rats (RLMs) and humans (HLMs). dPE was eliminated faster than dPB in both species. The incubation of dPB with RLMs and HLMs resulted in eight (B1–B8) and nine (B1–B9) metabolites, respectively, while both RLMs and HLMs converted dPE into 13 metabolites (E1–13). Structures of all the metabolites were proposed through comparing their mass data obtained via tandem mass spectrometry on an MSD ion trap system (IT‐MS/MS) coupled with high‐resolution mass measurement by time‐of‐flight mass spectrometry (TOF‐MS) with those of the respective parent compound. B1 and E1 were unambiguously identified as (−)‐cis‐khellactone. The formations of all the metabolites were NADPH‐dependent. Oxidation and hydrolysis were demonstrated to be two predominant metabolic pathways of dPB and dPE. Oxidation initiated at either the C‐3′ or C‐4′ substituent, while hydrolysis only started from the C‐3′ substituent. Fragmentation of all metabolites followed similar pathways to those of the parent pyranocoumarins. The information on metabolic properties of dPB and dPE and the mass fragmentation profiles of their metabolites obtained in the present study will aid in characterization of metabolic profiles of other angular‐type pyranocoumarins and further investigation of in vivo fates of these pyranocoumarins and the herb. Copyright © 2011 John Wiley & Sons, Ltd.
Physical signal modulation of time‐of‐flight mass analyzers increases precision and decreases noise
Authors: Hilmer Jonathan K. , Bothner Brian
Published: February 2011

Recently, an increased emphasis has been placed on the ability to make mass measurements with high accuracy and precision. The motivation for this is that high‐precision mass measurements, together with isotope intensity matching, permit confirmation of molecular formulas and de novo molecular formula prediction, both of which enhance the value of proteomics and metabolomics data. The confidence of mass‐based conclusions also depends on reliable estimates of uncertainty. However, determining the precision of a particular measurement remains a complicated process. For signals which are well‐resolved and of sufficient intensity, an often‐overlooked factor for high precision is the mass sampling frequency (abscissa, Δx). We have analyzed the impact of Δx on the centroid calculation of peak position, and find that existing quality standards, such as 4 or 5 samples per peak, may not be sufficient to achieve high precision. Time‐domain and m/z‐domain sampling frequency on time‐of‐flight (TOF) mass analyzers can be improved using a new method that we call Physical Signal Modulation (PSM). PSM allows very substantial improvements by decreasing Δx without requiring specialized hardware or digitizers. In addition to providing accuracy improvements, PSM also dramatically improves signal‐to‐noise ratios by removing coherent noise. Software to perform PSM data processing is available as part of the PySpecTools package. Copyright © 2011 John Wiley & Sons, Ltd.
Robust performance analysis for uncertain negative‐imaginary systems
Authors: Song Zhuoyue , Lanzon Alexander , Patra Sourav , Petersen Ian R.
Published: February 2011

Negative‐imaginary systems are important in engineering practice as this class of systems appears quite often in practical problems, for example, lightly damped flexible structures with collocated position sensors and force actuators. In this paper, an analytical framework for robust performance of uncertain negative‐imaginary systems is proposed. The results are obtained by transforming negative‐imaginary systems into a bounded‐real framework via the positive‐real property. This paper deals with all the significant technical difficulties that appear due to the transformation and the punctured j ω‐axis frequency condition of negative‐imaginary systems. The problem is equivalently cast into a structured singular value condition that gives a quantitative performance test for this class of systems. This result also gives an analytical framework for robust stability when the perturbations are mixture of bounded‐real and negative‐imaginary uncertainties. A numerical example is presented to show the usefulness of the proposed methods. Copyright © 2011 John Wiley & Sons, Ltd.
Robust impulsive control of motion systems with uncertain friction
Authors: van de Wouw N. , Leine R. I.
Published: February 2011

In this paper, we consider the robust set‐point stabilization problem for motion systems subject to friction. Robustness aspects are particularly relevant in practice, where uncertainties in the friction model are unavoidable. We propose an impulsive feedback control design that robustly stabilizes the set‐point for a class of position‐, velocity‐and time‐dependent friction laws with uncertainty. Moreover, it is shown that this control strategy guarantees the finite‐time convergence to the set‐point which is a favorable characteristic of the resulting closed loop from a transient performance perspective. The results are illustrated by means of a representative motion control example. Copyright © 2011 John Wiley & Sons, Ltd.
Standardization of Models and Methods Used to Assess Nanoparticles in Cardiovascular Applications
Authors: Fitzgerald Kathleen T. , Holladay Carolyn A. , McCarthy Cathal , Power Karen A. , Pandit Abhay , Gallagher William M.
Published: February 2011

Nanotechnology has the potential to revolutionize the management and treatment of cardiovascular disease. Controlled drug delivery and nanoparticle‐based molecular imaging agents have advanced cardiovascular disease therapy and diagnosis. However, the delivery vehicles (dendrimers, nanocrystals, nanotubes, nanoparticles, nanoshells, etc.), as well as the model systems that are used to mimic human cardiac disease, should be questioned in relation to their suitability. This review focuses on the variations of the biological assays and preclinical models that are currently being used to study the biocompatibility and suitability of nanomaterials in cardiovascular applications. There is a need to standardize appropriate models and methods that will promote the development of novel nanomaterial‐based cardiovascular therapies.
Scanning Transmission X‐Ray Microscopy as a Novel Tool to Probe Colloidal and Photonic Crystals
Authors: van Schooneveld Matti M. , Hilhorst Jan , Petukhov Andrei V. , Tyliszczak Tolek , Wang Jian , Weckhuysen Bert M. , de Groot Frank M. F. , de Smit Emiel
Published: February 2011

Photonic crystals consisting of nano‐ to micrometer‐sized building blocks, such as multiple sorts of colloids, have recently received widespread attention. It remains a challenge, however, to adequately probe the internal crystal structure and the corresponding deformations that inhibit the proper functioning of such materials. It is shown that scanning transmission X‐ray microscopy (STXM) can directly reveal the local structure, orientations, and even deformations in polystyrene and silica colloidal crystals with 30‐nm spatial resolution. Moreover, STXM is capable of imaging a diverse range of crystals, including those that are dry and inverted, and provides novel insights complementary to information obtained by benchmark confocal fluorescence and scanning electron microscopy techniques.
Vertical Arrays of Anisotropic Particles by Gravity‐Driven Self‐Assembly
Authors: Smith Benjamin D. , Kirby David J. , Keating Christine D.
Published: February 2011

Anisotropic particles assemble to spontaneously form columnar arrays. Hybrid nanotube/nanowire particles (silica nanotubes partially filled with metallic cores) deposit with their denser metallic ends towards the surface, orienting them vertically. Up to 84% are observed to be standing over a 0.64 cm2 area within 15 min. Standing percentage is found to be dependent on particle surface concentration.
Isomorphous Catena Transition Metal Squarates [MII(C4O4)(dmso)2(OH2)2] (M = Co, Mn) and Magnetic Investigation into their Solid Solution M = CoxMn1–x
Authors: Şerb Mihaela‐Diana , Speldrich Manfred , Lueken Heiko , Englert Ulli
Published: February 2011

The crystal structures of two new isomorphous transition metal squarato complexes [MII(C4O4)(dmso)2(OH2)2] [MII = CoII (3d7), MnII (3d5); dmso = dimethylsulfoxide] and their magnetic properties are reported. The compounds feature two symmetrically independent chains, in which 1,3‐bridging squarato ligands connect cations in distorted octahedral surroundings of pseudo‐symmetry D4h. From an equimolar solution of CoCl2·6H2O and MnCl2·2H2O a mixed‐metal coordination polymer crystallizes; it represents a solid solution and adopts the same structure as the corresponding monometallic compounds. The results of the diffraction experiment unambiguously proof the presence of both CoII and MnII cations in either independent site albeit no precise ratio between the metal cations involved may be deduced from these findings. The difference in the magnetic properties between CoII and MnII cations in the given ligand field has allowed us to establish their ratio in the solid solution more reliably than by X‐ray diffraction: Accounting for ligand field potential and spin‐orbit coupling of CoII and regarding MnII as a pure spin system, the calculations yielded a fraction of 73 % CoII in the mixed‐metal polymer. With respect to superexchange effects only weak antiferromagnetic interactions have been detected for the three coordination polymers.
The Crystal and Molecular Structures of Gold(I) Complexes Containing the Electron‐Rich P‐Donor Ligand Ph3PNPPh2
Authors: Böttcher Hans‐Christian , Lux Karin , Kidik Mustafa , Karaghiosoff Konstantin
Published: February 2011

The reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with an equimolar amount of the electron‐rich ligand N‐diphenylphosphino‐triphenylphosphinimine, Ph3PNPPh2, in THF afforded the new complex [AuCl(Ph3PNPPh2)] (1) in good yield. Furthermore, the reaction of [AuHCl4] with Ph3PNPPh2 in a molar ratio of 1:3 in dichloromethane at room temperature yielded the complex salt [Au(Ph3PNPPh2)2]Cl (2) as the dichloromethane solvate beside Ph3PNPPh2Cl2 as the side‐product of oxidation. The molecular structures of metal complexes 1 and 2 were determined by single‐crystal X‐ray diffraction. Because of the bulkiness of the ligand Ph3PNPPh2 no short intermolecular gold–gold interactions (aurophilic aggregation) could be observed in the solid‐state structures.
Newborn screening for congenital hypothyroidism in very‐low‐birth‐weight babies: the need for a second test
Authors: Bijarnia Sunita , Wilcken Bridget , Wiley Veronica C.
Published: February 2011

Background

Very‐low‐birth‐weight babies (VLBW) with hypothyroidism may show a delayed postnatal rise in thyroid stimulating hormone (TSH), mainly due to immaturity of the hypothalamic‐pituitary‐thyroid axis. Transient hypothyroidism is prevalent in VLBW babies and some affected babies are considered to need treatment. There is disagreement about whether a second screening test is needed in VLBW babies to detect all cases that need treatment.

Methods

We included in the study all babies with a birth weight ≤ 1,500 g born in New South Wales and the Australian Capital Territory between January 2006 and December 2008. Newborn screening samples for TSH measurement were taken in the first days of life and again at 1 month. During week 1, a blood‐spot TSH level of ≥20 mIU/L was considered positive, and at 1 month a positive level was ≥7 mIU/L, and triggered full investigation.

Results

In the cohort of 301,000 babies, 2,313 VLBW babies survived for testing, and 2,117 repeat screening samples were received. Forty‐three babies had transient hypothyroidism, with thyroid function normalising before 2 months of age, usually without treatment. Eighteen babies required treatment beyond 2 months of age (1:128 of surviving babies), 16 having had normal TSH results on initial testing, and 12 having levels below 6 mIU/L.

Conclusion

Significant hypothyroidism, transient or permanent, but persisting beyond 2 months of age is common in VLBW babies. There is a delayed rise in TSH in some, and secondary screening at 1 month of age detects babies deemed by local paediatric endocrinologists as needing treatment.
Preparation of Fat‐Liquor Based on Jojoba Oil Under Phase Transfer Catalysis
Authors: Nashy El‐Shahat H. A. , Megahed M. G. , Abd EL‐Ghaffar M. A.
Published: February 2011

Jojoba oil is of immense importance for industrial applications. There are a lot of published articles concerning its various uses in cosmetics, detergents, surfactants and lubricants. Therefore, this work was devoted to exploring its application for further use in the leather industry as a fat‐liquoring agent. The fat‐liquoring process is one important step in leather manufacturing, with the intention of obtaining leather of full, soft handle, flexibility, and pliability as well as improving its mechanical properties. The study involved preparation of jojoba fat‐liquor via a sulfitation process. An improvement of the sulfitation process based on combined SO3 content was achieved under phase transfer catalysis (PTC). Two differently prepared types of phase transfer catalyst of phosphonium and ammonium types were investigated, namely, benzyl tri‐phenyl phosphonium chloride (BTPP) and tri‐ethyl benzyl ammonium chloride (TEBA). The fat‐liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement of the texture of the treated leather by jojoba fat‐liquor as indicated in the scanning electron microscope (SEM) images was observed.
Goal-directed ultrasound in a limited resource healthcare setting and developing country
Authors: Elia Fabrizio , Campagnaro Tommaso , Salacone Paola , Casalis Sara
Published: February 2011

Background

In developing countries, access to diagnostic technology is limited by economic, social and geographical barriers. Diagnostic tools must be sustainable, effective and low cost.

Case

A 30-year-old man was admitted in a rural hospital with fever and chest pain and managed successfully with a goal-directed sonographic approach.

Conclusion

Ultrasound is a point of care, rapid, non-invasive and low-cost technology. Primary goal-directed ultrasound can be a high-impact diagnostic tool in scarce resource scenarios.
Kluver–Bucy syndrome in one case with systemic lupus erythematosus
Authors: Lin Hsiu‐Fen , Yeh Yi‐Chun , Chen Chien‐Fu , Chang Wei‐Chen , Chen Cheng‐Sheng
Published: February 2011

Kluver–Bucy syndrome (KBS) is a collection of neuropsychiatric symptoms, including visual agnosia (prosopagnosia), hypermetamorphosis, placidity, hypersexuality, and hyperorality. Although neuropsychiatric manifestation is prevalent in cases with systemic lupus erythematosus (SLE), only one literature reported a case with SLE that had KBS previously. In this article, a 37‐year‐old woman with SLE who developed KBS and other neuropsychiatric symptoms is presented. Brain imaging proved the relevant structural lesion. The possible explanation of pathogenesis of KBS in SLE is discussed.
On the whistling of corrugated pipes: effect of pipe length and flow profile
Authors: NAKIBOĞLU G. , BELFROID S. P. C. , GOLLIARD J. , HIRSCHBERG A.
Published: February 2011

Whistling behaviour of two geometrically periodic systems, namely corrugated pipes and multiple side branch systems, is investigated both experimentally and numerically. Tests are performed on corrugated pipes with various lengths and cavity geometries. Experiments show that the peak-whistling Strouhal number, where the maximum amplitude in pressure fluctuations is registered, is independent of the pipe length. Experimentally, a decrease of the peak-whistling Strouhal number by a factor of two is observed with increasing confinement ratio, i.e. the ratio of pipe diameter to cavity width. A numerical methodology that combines incompressible flow simulations with vortex sound theory is proposed to estimate the acoustic source power in periodic systems. The methodology successfully predicts the Strouhal number ranges of acoustic energy production/absorption and the nonlinear saturation mechanism responsible for the stabilization of the limit cycle oscillation. The methodology predicts peak-whistling Strouhal numbers in agreement with experiments and explains the dependence of the peak-whistling Strouhal number on the confinement ratio. Combined with an energy balance, the proposed methodology is used to estimate the acoustic fluctuation amplitudes.
Social Policy Digest Online
Authors: Bennett Fran , Jones Ken
Published: February 2011

The Social Policy Digest is a major online resource providing up-to-date listings of developments across the whole range of social policy issues – including links to source materials and related commentaries. The Digest is published by Cambridge University Press on behalf of the Social Policy Association.
Cok Vrooman (2009), Rules of Relief, Institutions of Social Security, and Their Impact. The Hague: The Netherlands Institute of Social Research. £205.99, pp. 542, pbk. – ERRATUM
Authors: Greve Bent
Published: February 2011

Within this Book Review the publisher and price of the book were incorrect. The publisher is The Netherlands Institute for Social Research and the price is $84.90. The publisher apologies for any inconvenience caused.
MATHEMATICAL METHODS IN ABŪ AL-WAFĀʾ'S ALMAGEST AND THE QIBLA DETERMINATIONS
Authors: Moussa Ali
Published: February 2011

The problem of the Qibla was one of the central issues in the scientific culture of Medieval Islam, and to solve it properly, one needed mathematics and observation. The mathematics consisted of two parts: plane trigonometry (to construct the trigonometric tables) and spherical trigonometry (as the problem belongs to spherical astronomy). Observation and its instruments were needed to find the geographical coordinates of Mecca and the given location; these coordinates (latitude, longitude) will be the input data in the formulas of the Qibla. In his Almagest, Abū al-Wafāʾ produced a brilliant work to solve the problem. He worked on both mathematics and observation, and reached accurate and easy “modern” solutions. In plane trigonometry, he introduced the trigonometric functions with new definitions, proved the formulas for sines, approximated the sine of degree one, and thus constructed the tables of sines and tangents with high accuracy. In spherical trigonometry, he proved four new spherical theorems, including the tangent rule (which was based on the new definitions and this rule allowed him to work out the easiest solution, as will be shown). In observation, he described three instruments which he used over several years in Baghdad. This paper is a detailed technical and analytical description of Abū al-Wafāʾ's mathematical methods and the Qibla determinations, supplemented with many important original Arabic texts with translation and commentary.
WIN WIN's Struggles with the Institutional Transfer of the EMILY's List Model to Japan: The Role of Accountability and Policy
Authors: GAUNDER ALISA
Published: February 2011

This article addresses the complexities of institutional transfer by exploring the case of EMILY's List and WIN WIN, two women's organizations in the US and Japan respectively that seek to increase the number of women in office by providing funds early in candidates’ campaigns. Specifically, it asks why WIN WIN has struggled to successfully implement the EMILY's List model in Japan. This article argues that differing institutional environments and cultures have less explanatory power than decisions made at the organization level. In particular, while differences in the political funding regimes and so-called ‘cultures of giving’ exist, they do not necessarily preclude the success of an EMILY's List-type organization in Japan. Instead, WIN WIN made significant strategic organizational decisions that have impeded its ability to have a significant impact on female candidacy at the national level. Specifically, WIN WIN's lack of accountability to its members combined with its broader commitment to gender consciousness have limited its success.
CONTINENTAL DIVIDE: ERNST CASSIRER AND MARTIN HEIDEGGER AT DAVOS, 1929—AN ALLEGORY OF INTELLECTUAL HISTORY
Authors: GORDON PETER ELI
Published: February 2011

The 1929 ‘Davos encounter’ between Martin Heidegger and Ernst Cassirer has long been viewed by intellectual historians as a paradigmatic event not only for its philosophical meaning but also for its apparently cultural-political ramifications. But such interpretations easily lend legitimacy to a broader and recently ascendant intellectual-historical trend that would reduce philosophy to an allegorical expression of ostensibly more ‘real’ or instrumentalist meanings. However, as this essay tries to show, the core of the dispute between Cassirer and Heidegger is irreducibly philosophical: the Davos debate brought into focus the emergent themes of the so-called “Kant-crisis” of the 1920s, and cast new light upon neo-Kantian doctrines as to the status of objectivity and the possibility for intersubjective consensus in both knowledge and ethics. The Davos encounter cannot be retroactively decided on political or cultural grounds, since it concerns just that unresolved tension between transcendentalism and hermeneutics that is itself constitutive of intellectual history as a discipline.
Allele mining in the gene pool of wild Solanum species for homologues of late blight resistance gene RB/Rpi-blb1
Authors: Pankin Artem , Sokolova Ekaterina , Rogozina Elena , Kuznetsova Maria , Deahl Kenneth , Jones Richard , Khavkin Emil
Published: February 2011

A coiled coil-nucleotide binding site-leucine-rich repeat gene RB/Rpi-blb1 isolated from Solanum bulbocastanum confers broad-spectrum resistance to Phytophthora infestans and is currently employed in potato breeding for durable late blight (LB) resistance. RB homologues were reported in several Solanum species; some of them retained defence function. Here, we report additional evidence on RB-like sequences in 21 Solanum species of the section Petota. The panel of Solanum species was screened with three RB-related PCR markers. RB-like sequences were found in every tested Solanum accession, suggesting universal distribution of RB structural homologues among Solanum genomes, while locus-specific RB-629 was found only in 15 species. Phylogenetic analysis of RB-629 sequences suggested a highly conservative pattern of polymorphisms that was neither species- nor series-specific. Apparently, duplication and evolution of RB-like loci preceded Solanum speciation. Marker presence and particular haplotypes were not immediately associated with high LB resistance.
A voltage-mode class-S power amplifier for the 450 MHz band
Authors: Wentzel Andreas , Meliani Chafik , Heinrich Wolfgang
Published: February 2011

This paper reports on a novel voltage-mode class-S power amplifier for the 450 MHz band, based on GaN–HEMT monolithic microwave integrated circuits (MMICs). It achieves a peak output power of 3.4 W for a single tone at 400 MHz, encoded in standard band-pass delta-sigma modulation with 1.6 Gbps sampling frequency. The corresponding efficiency is 38%, peaking at 52% for 0.5 W output power. In order to demonstrate the influence of coding efficiency, additional measurements using a periodic square-wave signal were performed (class-D operation), which yield a maximum output power of 7 W with 64% efficiency. To the author's knowledge, these are the best results in this frequency range achieved so far with the voltage-mode class-S configuration. The paper discusses behavior at power back-off and the influence of the loss mechanisms.
Semi-physical nonlinear circuit model with device/physical parameters for HEMTs
Authors: Otsuka Hiroshi , Oishi Toshiyuki , Yamanaka Koji , Thorsell Mattias , Andersson Kristoffer , Inoue Akira , Hirano Yoshihito , Angelov Iltcho
Published: February 2011

A nonlinear circuit model (NCM) with physical parameters is proposed for direct simulation of the RF characteristics of GaN high-electron-mobility transistors (GaN HEMTs) on the basis of device structure. The physical equations are used for the construction of the model in order to connect strongly the model parameters with the device/physical parameters. Hyperbolic tangent functions are used as the model equations to ensure good model convergence and rapid simulation (short simulation time). The usefulness of these equations is confirmed by technology computer aided design (TCAD) simulation. The number of model parameters for the nonlinear components (Ids, Cgs, Cgd) is reduced to 17 by using common physical parameters for modeling the drain current and capacitance. The accuracy of this model is verified by applying to GaN HEMTs. The modeled I–V and capacitance characteristics agree well with the measurement data over a wide voltage range. Furthermore, this model can be used for the accurate evaluation of S-parameters and large-signal RF characteristics.
Storm‐driven groundwater flow in a salt marsh
Authors: Wilson Alicia M. , Moore Willard S. , Joye Samantha B. , Anderson Joseph L. , Schutte Charles A.
Published: February 2011

Storms can cause significant groundwater flow in coastal settings, but prior studies of the effects of storms on groundwater flow and transport have largely focused on very large storms and used salinity as a tracer. We have little information about the effects of smaller storms on coastal flow and how storm‐induced variability affects key tidal wetlands like salt marshes, which may remain saline throughout a storm. Here we show that even the distant passage of a moderate storm can strongly increase groundwater flow and transport in salt marsh ecosystems and adjacent barrier islands. Groundwater monitoring and radium isotope tracer analyses revealed significant influx of saline creek water into the confined aquifer below the marsh platform, driven by storm surge. This pulse of fluids reached depths exceeding 5 m, and surge‐enhanced tides propagated through the aquifer to affect flow in the upland >100 m from the creek bank. Groundwater discharge from the marsh varied significantly prior to the storm, doubling during inundating tides compared to a period of noninundating neap tides. Storm surge then caused groundwater discharge to decline ∼50% compared to similar inundating tides. Ra‐ and nutrient‐poor creek water that entered the confined aquifer below the marsh was quickly enriched in nutrients and carbon, even on 12 h tidal cycles, so that nutrient discharge was likely proportional to groundwater discharge. Storm‐related flow could also drive significant contaminant discharge from developed coastlines. The enhanced transport and variability observed here likely affected hundreds of kilometers of the coastline impacted by the storm.
Time stability of catchment model parameters: Implications for climate impact analyses
Authors: Merz Ralf , Parajka Juraj , Blöschl Günter
Published: February 2011

Climate impact analyses are usually based on driving hydrological models by future climate scenarios, assuming that the model parameters calibrated to past runoff are representative of the future. In this paper we calibrate the parameters of a conceptual rainfall‐runoff model to six consecutive 5 year periods between 1976 and 2006 for 273 catchments in Austria and analyze the temporal change of the calibrated parameters. The calibrated parameters representing snow and soil moisture processes show significant trends. For example, the parameter controlling runoff generation doubled, on average, in the 3 decades. Comparisons of different subregions, comparisons with independent data sets, and analyses of the spatial variability of the model parameters indicate that these trends represent hydrological changes rather than calibration artifacts. The trends can be related to changes in the climatic conditions of the catchments such as higher evapotranspiration and drier catchment conditions in the more recent years. The simulations suggest that the impact on simulated runoff of assuming time invariant parameters can be very significant. For example, if using the parameters calibrated to 1976–1981 for simulating runoff for the period 2001–2006, the biases of median flows are, on average, 15% and the biases of high flows are about 35%. The errors increase as the time lag between the simulation and calibration periods increases. The implications for hydrologic prediction in general and climate impact analyses in particular are discussed.
Symmetrical modification within a nucleosome is not required globally for histone lysine methylation
Authors: Chen Xiuzhen , Xiong Jun , Xu Mo , Chen She , Zhu Bing
Published: February 2011

Two copies of each core histone exist in every nucleosome; however, it is not known whether both histones within a nucleosome are required to be symmetrically methylated at the same lysine residues. We report that for most lysine methylation states, wild‐type histones paired with mutant, unmethylatable histones in mononucleosomes have comparable methylation levels to bulk histones. Our results indicate that symmetrical histone methylation is not required on a global scale. However, wild‐type H4 histones paired with unmethylatable H4K20R histones showed reduced levels of H4K20me2 and H4K20me3, suggesting that some fractions of these modifications might exist symmetrically, and enzymes mediating these modifications might, to some extent, favour nucleosome substrates with premethylated H4K20.
A Critical Evaluation of Gestural Stiffness Estimations in Speech Production Based on a Linear Second-Order Model
Authors: Fuchs Susanne , Perrier Pascal , Hartinger Mariam
Published: February 2011

Purpose

Linear second-order models have often been used to investigate properties of speech production. However, these models are inaccurate approximations of the speech apparatus. This study aims at assessing how reliably stiffness can be estimated from kinematics with these models.

Method

Articulatory movements were collected for 9 speakers of German during the production of reiterant CVCV words at varying speech rates. Velocity peaks, movement amplitudes, and gesture durations were measured. In the context of an undamped model, 2 stiffness estimations were compared that should theoretically yield the same result. In the context of a damped model, gestural stiffness and damping were calculated for each gesture.

Results

Numerous cases were found in which stiffness estimations based on the undamped model contradicted each other. Less than 80% of the data were found to be compatible with the properties of the damped model. Stiffness tends to decrease with gestural duration. However, it is associated with a large, unrealistic damping dispersion, making stiffness estimations from kinematic data to a large extent unreliable.

Conclusion

Any conclusions about speech control based on stiffness estimations using linear second-order models should therefore be considered with caution.
Children’s Performance in Complex Listening Conditions: Effects of Hearing Loss and Digital Noise Reduction
Authors: Pittman Andrea
Published: February 2011

Purpose

To determine the effect of hearing loss (HL) on children’s performance for an auditory task under demanding listening conditions and to determine the effect of digital noise reduction (DNR) on that performance.

Method

Fifty children with normal hearing (NH) and 30 children with HL (8–12 years of age) categorized words in the presence of auditory or visual competitors, or both. Stimuli were presented at 50 dB SPL at a 0-dB signal-to-noise ratio. Children with HL were fitted with behind-the-ear hearing aids that had DNR technology. When DNR was activated, output decreased 4 dB, and signal-to-noise ratio increased 2 dB.

Results

Significant main effects of group and age were observed. Performance for both groups decreased in noise, and the performance of the children with HL decreased further with the addition of the visual task. However, performance was unaffected by DNR. For the children with HL, stimulus audibility and communication skills contributed significantly to performance, whereas their history of hearing aid use did not.

Conclusions

For the children with HL, tasks unrelated to hearing interfered with their ability to participate in the auditory task. Consistent with previous studies, performance in noise was unaffected by DNR.