bluuebunny/crossref_metadata_2025 huggingface dataset:
Bivalent and co-operative binding of complement Factor H to heparan sulfate and heparin
Authors: Khan Sanaullah , Nan Ruodan , Gor Jayesh , Mulloy Barbara , Perkins Stephen J.
Published: April 2012

FH (Factor H) with 20 SCR (short complement regulator) domains is a major serum regulator of complement, and genetic defects in this are associated with inflammatory diseases. Heparan sulfate is a cell-surface glycosaminoglycan composed of sulfated S-domains and unsulfated NA-domains. To elucidate the molecular mechanism of binding of FH to glycosaminoglycans, we performed ultracentrifugation, X-ray scattering and surface plasmon resonance with FH and glycosaminoglycan fragments. Ultracentrifugation showed that FH formed up to 63% of well-defined oligomers with purified heparin fragments (equivalent to S-domains), and indicated a dissociation constant Kd of approximately 0.5 μM. Unchanged FH structures that are bivalently cross-linked at SCR-7 and SCR-20 with heparin explained the sedimentation coefficients of the FH–heparin oligomers. The X-ray radius of gyration, RG, of FH in the presence of heparin fragments 18–36 monosaccharide units long increased significantly from 10.4 to 11.7 nm, and the maximum lengths of FH increased from 35 to 40 nm, confirming that large compact oligomers had formed. Surface plasmon resonance of immobilized heparin with full-length FH gave Kd values of 1–3 μM, and similar but weaker Kd values of 4–20 μM for the SCR-6/8 and SCR-16/20 fragments, confirming co-operativity between the two binding sites. The use of minimally-sulfated heparan sulfate fragments that correspond largely to NA-domains showed much weaker binding, proving the importance of S-domains for this interaction. This bivalent and co-operative model of FH binding to heparan sulfate provides novel insights on the immune function of FH at host cell surfaces.
Core contribution to magnetotransport of ferromagnetic dots in vortex state
Authors: Segal A. , Gerber A.
Published: April 2012

We study the influence of the vortex core on magnetotransport of ferromagnetic dots in a vortex state. The extraordinary Hall effect generated in the core region has a different field symmetry compared to contributions of anisotropic magnetoresistance and the planar Hall effect, which can be used to detect chirality and polarity of the vortex. We propose a method for realization of two-bit per dot magnetic random access memory, in which two states are contributed by clockwise and counter-clockwise chirality and two by up and down core polarity. Dependence of the signal on vortex location, core diameter, and other parameters is discussed.
Vibrational properties of the compressed and the relaxed 1,4,5,8-naphthalene-tetracarboxylic dianhydride monolayer on Ag(111)
Authors: Braatz Carolin R. , Öhl Gregor , Jakob Peter
Published: April 2012

Layers of 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA) grown on Ag(111) at about 80 K have been investigated using Fourier transform infrared spectroscopy, spot profile analysis low-energy electron diffraction, and temperature programmed desorption. Specifically, the compressed and the relaxed monolayer, as well as the transformation between the two ordered phases have been analyzed in detail. It is found that the two monolayer phases display distinctly different vibrational spectra and can thus be discriminated with high accuracy and sensitivity. For the NTCDA/Ag(111) monolayer strong in-plane vibrational modes point at a marked dynamic charge transfer between molecule and metal substrate and provide clear evidence for an efficient electronic coupling to the Ag(111) surface in conjunction with a partially filled electronic level at the Fermi energy. The bilayer, on the other hand, is largely electronically decoupled from the substrate and, according to the vanishing infrared-active in-plane vibrational modes, is oriented parallel to the surface. On the basis of spectroscopic data the metastable nature of the bilayer phase is identified as such, leading to an improved understanding of processes encountered in the course of layer preparation and resolving inconsistencies reported in the literature.
Hydrodynamic cavitation in microsystems. II. Simulations and optical observations
Authors: Medrano M. , Pellone C. , Zermatten P. J. , Ayela F.
Published: April 2012

Numerical calculations in the single liquid phase and optical observations in the two-phase cavitating flow regime have been performed on microdiaphragms and microventuris fed with deionized water. Simulations have confirmed the influence of the shape of the shrinkage upon the contraction of the jet, and so on the localisation of possible cavitating area downstream. Observations of cavitating flow patterns through hybrid silicon–pyrex microdevices have been performed either via a laser excitation with a pulse duration of 6 ns, or with the help of a high-speed camera. Recorded snapshots and movies are presented. Concerning microdiaphragms, it is confirmed that very high shear rates downstream the diaphragms are the cause of bubbly flows. Concerning microventuris, a gaseous cavity forms on a boundary downstream the throat. As a consequence of a microsystem instability, the cavity displays a high frequency pulsation. Low values Strouhal numbers are associated to such a sheet cavitation. Moreover, when the intensity of the cavitating flow is reduced, there is a mismatch between the frequency of the pulsation of the cavity and the frequency of shedded clouds downstream the channel. That may be the consequence of viscous effects limiting the impingement of a re-entrant liquid jet on the attached cavity.
Tunable deformation and electronic properties of single-walled ZnO nanotubes under a transverse electric field
Authors: Wang Yanzong , Wang Baolin , Zhang Qinfang , Zhao Jijun , Shi Daning , Yunoki Seiji , Kong Fanjie , Xu Ning
Published: April 2012

The effects of the electric field on the radial deformation and electronic properties of armchair and zigzag single-walled ZnO nanotubes are investigated by the density functional theory. Under the transverse electric field, the circular cross-sections of ZnO nanotubes are deformed to elliptic. In addition, the bandgap of ZnO nanotube gradually reduced with the increasing electric field strength. Such field-induced modulation effect is enhanced in ZnO nanotubes with larger tube diameter, but is not sensitive to the chirality. The mechanisms of the radial deformation and the variations of bandgaps of the ZnO nanotubes are analyzed.
Computer simulation of linkage of two ring chains
Authors: Xiong Zhimin , Han Charles C. , Liao Qi
Published: April 2012

We performed off-lattice Monte Carlo simulations of links of two model ring chains with chain length N up to 32 768 in the theta solution or amorphous bulk state by using a random walk model (Model I), and molecular dynamics simulations of two model ring chains in solution with excluded volume interaction (Model II) to investigate topological effects on the geometry of link and ring conformation. In the case of Model I, the mean squared linking number, its distribution, and the size of two chains with fixed linking number are investigated. Our simulation results confirm the previous theoretical prediction that the mean squared linking number decays as $pe^{ - qs^2 }$pe−qs2 with the distance of centers of chain mass s, where p and q are found to be chain length dependent and q asymptotically approaches to 0.75 as chain length increases. The linking number distribution of two chains has a universal form for long chains, but our simulation results clearly show that the distribution function deviates from the Gaussian distribution, a fact not predicted by any previous theoretical work. A scaling prediction is proposed to predict the link size, and is checked for our simulations for the Model II. The simulation results confirmed the scaling prediction of the blob picture that the link with linking number m occupies a compact volume of m blobs, and the size of the link is asymptotic to RL ≈ bNνm1/3 − ν, where N is the chain length, and v is the Flory exponent of polymer in solutions.
High-temperature phonon spectra of multiferroic BiFeO3 from inelastic neutron spectroscopy
Authors: Zbiri Mohamed , Schober Helmut , Choudhury Narayani , Mittal Ranjan , Chaplot Samrath L. , Patwe Sadequa J. , Achary Srungarpu N. , Tyagi Avesh K.
Published: April 2012

We report inelastic neutron scattering measurements of the phonon spectra in a pure powder sample of the multiferroic material BiFeO3. A high-temperature range was covered to unravel the changes in the phonon dynamics across the Néel (TN ∼ 650 K) and Curie (TC ∼ 1100 K) temperatures. Experimental results are accompanied by ab initio lattice dynamical simulations of phonon density of states to enable microscopic interpretations of the observed data. The calculations reproduce well the observed vibrational features and provide the partial atomic vibrational components. Our results reveal clearly the signature of three different phase transitions both in the diffraction patterns and phonon spectra. The phonon modes are found to be most affected by the transition at the TC. The spectroscopic evidence for the existence of a different structural modification just below the decomposition limit (TD ∼ 1240 K) is unambiguous indicating strong structural changes that may be related to oxygen vacancies and concomitant Fe3+ → Fe2+ reduction and spin transition.
Above-room-temperature photoluminescence from a strain-compensated Ge/Si0.15Ge0.85 multiple-quantum-well structure
Authors: Wu P. H. , Dumcenco D. , Huang Y. S. , Hsu H. P. , Lai C. H. , Lin T. Y. , Chrastina D. , Isella G. , Gatti E. , Tiong K. K.
Published: April 2012

Photoluminescence (PL) of a strain-compensated Ge/Si0.15Ge0.85 multiple-quantum-well (MQW) structure was studied above room temperature, in the range of 300–440 K. Both direct and indirect radiative recombination PL features were observed. The relative intensity of direct to indirect recombination markedly increases with the increase of temperature. The enhancement of PL from direct recombination above RT has been attributed to the thermal excitation of carriers from L-type to Γ-type confined states. This extends the potential applicability of Ge/SiGe MQW as light emitters on a Si-based platform and is favorable for applications in metal-oxide-semiconductor integrated circuits which normally operate above RT.
Note: Multiplexed multiple-tau auto- and cross-correlators on a single field programmable gate array
Authors: Mocsár G. , Kreith B. , Buchholz J. , Krieger J. W. , Langowski J. , Vámosi G.
Published: April 2012

We introduce a new multiple-tau hardware correlator design for computing fluorescence correlation functions (CFs) in real time. Use of hardware resources is minimized by scheduling the computation of different segments of the CFs on a single correlator block. Simultaneous calculation of two multiple-tau autocorrelation (ACFs) and two cross-correlation functions (CCFs) is implemented in LabVIEW on a National Instruments field programmable gate array (FPGA) card with a minimal sampling time of 400 ns. Raw data are stored with a time resolution of 50 ns. The design can be easily adapted to other FPGA cards and extended to more inputs.
Note: Development of a compact x-ray particle image velocimetry for measuring opaque flows. II. Three-dimensional velocity field reconstruction
Authors: Jung Sung Yong , Lee Sang Joon
Published: April 2012

An x-ray particle image velocimetry (PIV) system using a cone-beam type x-ray was developed. The field of view and the spatial resolution are 36 × 24.05 mm2 and 20 μm, respectively. The three-dimensional velocity field was reconstructed by adopting the least squares minimum residue and simultaneous multiplicative algebraic reconstruction techniques. According to a simulation study with synthetic images, the reconstructions were acceptable with 7 projections and 50 iterations. The reconstructed and supplied flow rates differed by only about 6.49% in experimental verification. The x-ray tomographic PIV system would be useful for 3D velocity field information of opaque flows.
The discharge of fine silica sand in a silo under different ambient air pressures
Authors: Hsiau Shu-San , Liao Chun-Chung , Lee Jie-Hsien
Published: April 2012

Silos are widely used for the industrial scale handling and transportation of powdered and granular materials. The process of discharging powder in a silo involves the flow of both solid particles and an interstitial fluid, usually air. In this study, we experimentally investigate the effects of particle size and ambient pressure on the discharge process in open- and closed-top silos. The discharge rate, pressure drop, and pressure recovery rate are measured and discussed. The results show that the particle size, the diameter of the orifice, and the ambient pressure significantly influence the process of discharge. The effect of air flow is stronger on fine-powdered flow in a closed-top silo. The results indicate that the effects of air flow could be reduced by lowering the ambient pressure. In addition, a normalized critical pressure can be defined beyond which the discharge rate increases dramatically. With reduced ambient pressure, this normalized critical pressure decreases with increasing particle size. Finally, the experimental results are compared with results calculated using the Beverloo equation and Darcy's law.
Structures of the vorticity tube segment in turbulence
Authors: Wang Lipo
Published: April 2012

To address the geometrical properties of the turbulent velocity vector field, a new concept named streamtube segment has been developed recently [L. Wang, “On properties of fluid turbulence along streamlines,” J. Fluid Mech. 648, 183–203 (2010)10.1017/S0022112009993041]. According to the vectorial topology, the entire velocity field can be partitioned into the so-called streamtube segments, which are organized in a non-overlapping and space-filling manner. In principle, properties of turbulent fields can be reproduced from those of the decomposed geometrical units with relatively simple structures. A similar idea is implemented to study the turbulent vorticity vector field using the vorticity tube segment structure. Differently from the conventional vortex tubes, vorticity tube segments are space-filling and can be characterized by non-arbitrary parameters, which enables a more quantitative description rather than just an illustrative explanation of turbulence behaviors. From analyzing the direct numerical simulation data, the topological and dynamical properties of vorticity tube segments are explored. The characteristic parameters have strong influence on some conditional statistics, such as the enstrophy production and the probability density function of vorticity stretching. Consequently the common knowledge in turbulence dynamics that vorticity are more stretched than compressed need to be rectified in the vorticity tube segment context.
A Review of the Use of Ultrasonography in Fish Reproduction
Authors: Novelo Noel D , Tiersch Terrence R
Published: April 2012

Ultrasound imaging analysis involves development of an effective combination of physical properties, equipment, instrument settings, and protocols. This review focuses on the application of ultrasonography to fish reproduction. The goal was to assemble a comprehensive reference data set to serve as a decision-enabling tool for potential users. The specific objectives were to (1) identify the ultrasound equipment, settings, and procedures used during examination, (2) review the fish handling procedures used during examination, and (3) review current data on sex identification and reproduction indices developed using ultrasonography. The 27 studies selected for inclusion in this review represent 21 fish species. Most (96%) of the studies reported the model name for the ultrasound unit, but only 19% reported the probe model. The most reported probe features were the frequency capability (96% of the studies) and array format (linear, sector, or annular; 81%). The majority of the studies (89%) did not report any of the control settings used. The combinations of handling and ultrasound procedures were variable even within the same species, and the majority (78%) of the studies included a form of restraint. None of the studies simultaneously integrated the use of unrestrained, unanesthetized, submersed fish with a submersed waterproof probe, which would enable the use of water as a transmission medium for ultrasound. Size, life stage, gonadal growth of reproductively active adults, and fish morphology influenced the ability to use ultrasonography for sex identification and the development and application of qualitative and quantitative reproductive indices. The utility of ultrasonography in fish reproduction has been repeatedly validated, and innovative indices for noninvasive use have been developed. However, this review identifies a clear lack of consistency in reporting of instrument settings and handling procedures and provides suggestions for standardizing the use of ultrasonography with aquatic species.
A Multicenter Study ofClostridium difficileInfection—Related Colectomy, 2000—2006
Authors: Kasper Amelia M. , Nyazee Humaa A. , Yokoe Deborah S. , Mayer Jeanmarie , Mangino Julie E. , Khan Yosef M. , Hota Bala , Fraser Victoria J. , Dubberke Erik R. ,   Centers for Disease Control and Prevention Epicenters Program
Published: April 2012

Objective.

To assessClostridium difficileinfection (CDI)-related colectomy rates by CDI surveillance definitions and over time at multiple healthcare facilities.

Setting.

Five university-affiliated acute care hospitals in the United States.

Design and Methods.

Cases of CDI and patients who underwent colectomy from July 2000 through June 2006 were identified from 5 US tertiary care centers. Monthly CDI-related colectomy rates were calculated as the number of CDI-related colectomies per 1,000 CDI cases, and cases were categorized according to recommended surveillance definitions. Logistic regression was performed to evaluate risk factors for CDI-related colectomy.

Results.

In total, 8,569 cases of CDI were identified, and 75 patients underwent CDI-related colectomy. The overall colectomy rate was 8.7 per 1,000 CDI cases. The CDI-related colectomy rate ranged from 0 to 23 per 1,000 CDI episodes across hospitals. The colectomy rate for healthcare-facility-onset CDI was 4.3 per 1,000 CDI cases, and that for community-onset CDI was 16.5 per 1,000 CDI cases (P< .05). There were significantly more CDI-related colectomies at hospitals B and C (P< .05).

Conclusions.

The overall CDI-related colectomy rate was low, and there was no significant change in the CDI-related colectomy rate over time. Onset of disease outside the study hospital was an independent risk factor for colectomy.
Blood Culture Collection through Peripheral Intravenous Catheters Increases the Risk of Specimen Contamination among Adult Emergency Department Patients
Authors: Self Wesley H. , Speroff Theodore , McNaughton Candace D. , Wright Patty W. , Miller Geraldine , Johnson James G. , Daniels Titus L. , Talbot Thomas R.
Published: April 2012

Five hundred five blood cultures collected through a peripheral intravenous catheter (PIV) in an emergency department were matched to cultures obtained by dedicated venipuncture from the same patient within 10 minutes. The relative risk of contamination for cultures collected through PIVs compared with dedicated venipuncture was 1.83 (95% confidence interval, 1.08–3.11).
Effectiveness of Selected Surgical Masks in Arresting Vegetative Cells and Endospores When Worn by Simulated Contagious Patients
Authors: Green Christopher F. , Davidson Craig S. , Panlilio Adelisa L. , Jensen Paul A. , Jin Yan , Gibbs Shawn G. , Scarpino Pasquale V.
Published: April 2012

Objective.

The objective of this study was to quantify the effectiveness of selected surgical masks in arresting vegetative cells and endospores in an experimental model that simulated contagious patients.

Setting.

Laboratory.

Methods.

Five commercially available surgical masks were tested for their ability to arrest infectious agents. Surgical masks were placed over the nose and mouth of mannequin head forms (Simulaids adult model Brad CPR torso). The mannequins were retrofitted with a nebulizer attached to an automated breathing simulator calibrated to a tidal volume of 500 mL/breath and a breathing rate of 20 breaths/min, for a minute respiratory volume of 10 L/min. Aerosols of endospores or vegetative cells were generated with a modified microbiological research establishment-type 6-jet collision nebulizer, while air samples were taken with all-glass impinger (AGI-30) samplers downstream of the point source. All experiments were conducted in a horizontal bioaerosol chamber.

Results.

Mean arrestance of bioaerosols by the surgical masks ranged from 48% to 68% when the masks were challenged with endospores and from 66% to 76% when they were challenged with vegetative cells. When the arrestance of endospores was evaluated, statistical differences were observed between some pairs, though not all, of the models evaluated. There were no statistically significant differences in arrestance observed between models of surgical masks challenged with vegetative cells.

Conclusions.

The arrestance of airborne vegetative cells and endospores by surgical masks worn by simulated contagious patients supports surgical mask use as one of the recommended cough etiquette interventions to limit the transmission of airborne infectious agents.
Effects of Chlorhexidine Oral Decontamination on Respiratory Colonization during Mechanical Ventilation in Intensive Care Unit Patients
Authors: Postma Douwe F. , Sankatsing Sanjay U. C. , Thijsen Steven F. T. , Endeman Henrik
Published: April 2012

We conducted a retrospective cohort study to assess respiratory colonization before and after the use of chlorhexidine oral decontamination among a cohort of intensive care unit patients who received mechanical ventilation. We observed a decrease in the prevalence of Enterobacteriaceae and an increase in the incidence of fungal colonization. Chlorhexidine oral decontamination might have a differential effect on respiratory colonization.
Inactivation of a 25.5 µm Enterococcus faecalis biofilm by a room-temperature, battery-operated, handheld air plasma jet
Authors: Pei X , Lu X , Liu J , Liu D , Yang Y , Ostrikov K , Chu Paul K , Pan Y
Published: April 2012

Effective biofilm inactivation using a handheld, mobile plasma jet powered by a 12 V dc battery and operated in open air without any external gas supply is reported. This cold, room-temperature plasma is produced in self-repetitive nanosecond discharges with current pulses of ∼100 ns duration, current peak amplitude of ∼6 mA and repetition rate of ∼20 kHz. It is shown that the reactive plasma species penetrate to the bottom layer of a 25.5 µm-thick Enterococcus faecalis biofilm and produce a strong bactericidal effect. This is the thickest reported biofilm inactivated using room-temperature air plasmas.
First Report of Alternaria petroselini Causing Leaf Blight of Fennel in Spain
Authors: Bassimba D. D. M. , Mira J. L. , Baixauli C. , Vicent A.
Published: April 2012

Fennel (Foeniculum vulgare Mill.) is an aromatic herb widely cultivated in Mediterranean areas for culinary and medicinal uses. In 2010, symptoms consisting of leaf blight and necrosis were observed in commercial organic fennel production areas in Valencia Province in east-central Spain. Disease incidence in affected fields was approximately 20%. Symptomatic leaves from four fields were surface disinfected with 0.5% NaOCl for 2 min, and small fragments from necrotic lesions were then plated on potato dextrose agar (PDA) amended with 0.5 g of streptomycin sulfate/liter. After 7 days at 25°C, isolates of the genus Alternaria were consistently isolated. Single conidium cultures were grown on PDA and V8 agar for morphological examination. On both agar media, colonies were dark olive brown without production of pigments. On V8 agar, conidia were solitary, darkly pigmented, and predominantly ovoid-subsphaeroid. Mature conidia were 25 to 59 × 12 to 23 μm with up to six to seven transepta and one to three longisepta. The 5.8S, ITS2, and 28S ribosomal RNA (rRNA) regions were amplified with the primers ITS3 and ITS4 (3) from DNA extracted from the isolate IVIA-A029, and sequenced (GenBank Accession No. JQ240204). The sequence had 100% identity (total score 399, 97% coverage) with that of Alternaria petroselini (Neergard) Simmons strain EGS 09-159 (GenBank Accession No. AF229454.1) (1). Pathogenicity tests were conducted on four 3-month-old fennel plants (cv. Giotto) by spraying a conidial suspension of the fungus (10 ml/plant, 103 conidia/ml of water). Four control plants were sprayed with sterile, distilled water. Plants were covered with plastic bags and incubated in a growth chamber for 72 h at 25°C. Leaf necrosis was visible on inoculated plants after 4 days, but symptoms were not observed on control plants. The fungus was reisolated from leaf lesions on inoculated plants, but not from leaves of control plants, confirming Koch's postulates. On the basis of the morphological (2), molecular, and pathogenicity data, the disease was identified as Alternaria leaf blight of fennel caused by A. petroselini. To our knowledge, this is the first report of A. petroselini in Spain.

References: (1) B. M. Pryor and R. L. Gilbertson. Mycol. Res. 104:1312, 2000. (2) E. G. Simmons. Alternaria: An Identification Manual. CBS Fungal Biodiversity Centre, Utrecht, The Netherlands, 2007. (3) T. J. White et al. Pages 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.
A Cut-Stem Inoculation Technique to Evaluate Soybean for Resistance to Macrophomina phaseolina
Authors: Twizeyimana M. , Hill C. B. , Pawlowski M. , Paul C. , Hartman G. L.
Published: April 2012

Charcoal rot of soybean is caused by the fungal pathogen Macrophomina phaseolina. Effective and reliable techniques to evaluate soybean for resistance to this fungus are needed to work toward a management scheme that would utilize host resistance. Three experiments were conducted to investigate the use of a cut-stem inoculation technique to evaluate soybean genotypes for resistance to M. phaseolina. The first experiment compared aggressiveness of M. phaseolina isolates collected from soybean on different soybean genotypes. Significant (P < 0.05) differences among the isolates and genotypes for relative area under disease progress curve (RAUDPC) were found without a significant isolate–genotype interaction. The second experiment compared 14 soybean genotypes inoculated with M. phaseolina in multiple trials conducted in two environments, the greenhouse and growth chamber. Significant (P < 0.05) differences among environments and highly significant (P < 0.001) differences among soybean genotypes for RAUDPC were found. The environment–genotype interaction was nonsignificant (P > 0.05). Soybean genotypes DT97-4290, DT98-7553, DT98-17554, and DT99-16864 had significantly (P < 0.05) lower RAUDPC than 7 of the 14 genotypes. The third experiment evaluated resistance in selected Phaseolus spp. and soybean genotypes. The range of RAUDPC for Phaseolus spp. was similar to that of soybean. The Phaseolus lunatus ‘Bush Baby Lima’ had significantly (P < 0.05) lower RAUDPC than P. vulgaris genotypes evaluated. The cut-stem inoculation technique, which has several advantages over field tests, successfully distinguished differences in aggressiveness among M. phaseolina isolates and relative differences among soybean genotypes for resistance to M. phaseolina comparable with results of field tests.
Effect of solid surface charge on the binding behaviour of a metal-binding peptide
Authors: Donatan Senem , Sarikaya Mehmet , Tamerler Candan , Urgen Mustafa
Published: April 2012

Over the last decade, solid-binding peptides have been increasingly used as molecular building blocks coupling bio- and nanotechnology. Despite considerable research being invested in this field, the effects of many surface-related parameters that define the binding of peptide to solids are still unknown. In the quest to control biological molecules at solid interfaces and, thereby, tailoring the binding characteristics of the peptides, the use of surface charge of the solid surface may probably play an important role, which then can be used as a potential tuning parameter of peptide adsorption. Here, we report quantitative investigation on the viscoelastic properties and binding kinetics of an engineered gold-binding peptide, 3RGBP
1,
adsorbed onto the gold surface at different surface charge densities. The experiments were performed in aqueous solutions using an electrochemical dissipative quartz crystal microbalance system. Hydrodynamic mass, hydration state and surface coverage of the adsorbed peptide films were determined as a function of surface charge density of the gold metal substrate. Under each charged condition, binding of 3rGBP
1
displayed quantitative differences in terms of adsorbed peptide amount, surface coverage ratio and hydration state. Based on the intrinsically disordered structure of the peptide, we propose a possible mechanism for binding of the peptide that can be used for tuning surface adsorption in further studies. Controlled alteration of peptide binding on solid surfaces, as shown here, may provide novel methods for surface functionalization used for bioenabled processing and fabrication of future micro- and nanodevices.
Floquet stability analysis of the longitudinal dynamics of two hovering model insects
Authors: Wu Jiang Hao , Sun Mao
Published: April 2012

Because of the periodically varying aerodynamic and inertial forces of the flapping wings, a hovering or constant-speed flying insect is a cyclically forcing system, and, generally, the flight is not in a fixed-point equilibrium, but in a cyclic-motion equilibrium. Current stability theory of insect flight is based on the averaged model and treats the flight as a fixed-point equilibrium. In the present study, we treated the flight as a cyclic-motion equilibrium and used the Floquet theory to analyse the longitudinal stability of insect flight. Two hovering model insects were considered—a dronefly and a hawkmoth. The former had relatively high wingbeat frequency and small wing-mass to body-mass ratio, and hence very small amplitude of body oscillation; while the latter had relatively low wingbeat frequency and large wing-mass to body-mass ratio, and hence relatively large amplitude of body oscillation. For comparison, analysis using the averaged-model theory (fixed-point stability analysis) was also made. Results of both the cyclic-motion stability analysis and the fixed-point stability analysis were tested by numerical simulation using complete equations of motion coupled with the Navier–Stokes equations. The Floquet theory (cyclic-motion stability analysis) agreed well with the simulation for both the model dronefly and the model hawkmoth; but the averaged-model theory gave good results only for the dronefly. Thus, for an insect with relatively large body oscillation at wingbeat frequency, cyclic-motion stability analysis is required, and for their control analysis, the existing well-developed control theories for systems of fixed-point equilibrium are no longer applicable and new methods that take the cyclic variation of the flight dynamics into account are needed.
Newton's gift to Roger Cotes
Authors: Bradley Bruce
Published: April 2012

In 1712 Isaac Newton sent a portrait of himself to Roger Cotes, who was then working with Newton as the editor of the second edition of Newton's
Principia
. Cotes acknowledged the gift with thanks in a letter to Newton, but the identity of the portrait, presumed to be an engraving done from one of the original portraits in oil, is a mystery. There are only a few engraved portraits to consider as possibilities. Two of them have been suggested as the portrait that Newton sent to Cotes, but an examination of the dates of those engravings rules out that possibility. A third possibility exists as a unique print in the collection of the Wellcome Library, and it now seems a better, if not the only, candidate.
The Radium Committee of the Royal Society and the fate of the substances purchased by it
Authors: Todd Neil
Published: April 2012

In this article, documents relating to the history of the Radium Committee of the Royal Society are collated for the first time. Founded in 1903, the committee had its status enhanced in 1904, when the Goldsmiths' Company donated £1000 for the establishment of a Radium Research Fund. Two years later the fund was used to purchase 500 kg of pitchblende residues from the Austrian government. The French chemist Armet de Lisle was contracted to perform the first stage of extraction, and the process of purification was performed at the Government Laboratory during 1907 by the Government Analyst, T. E. Thorpe, yielding an estimated 70 mg of radium chloride. In 1914 the unexpended balance of about £500 was awarded to Ernest Rutherford, but the bulk was not used until 1921, when Rutherford had moved to Cambridge. The fund was then used to purchase radium that had been on loan to him from Austria before World War I. After Rutherford's death in 1937 the Committee was wound up, and the Society's radium was controlled on a more
ad hoc
basis. After Thorpe's work in 1907, the radium was lent out successively to several leading scientists until its existence was last recorded in 1953.
Genetic Analysis of Strawberry Fruit Aroma and Identification ofO-Methyltransferase FaOMTas the Locus Controlling Natural Variation in Mesifurane Content
Authors: Zorrilla-Fontanesi Yasmín , Rambla José-Luis , Cabeza Amalia , Medina Juan J. , Sánchez-Sevilla José F. , Valpuesta Victoriano , Botella Miguel A. , Granell Antonio , Amaya Iraida
Published: April 2012

Improvement of strawberry (Fragaria × ananassa) fruit flavor is an important goal in breeding programs. To investigate genetic factors controlling this complex trait, a strawberry mapping population derived from genotype ‘1392’, selected for its superior flavor, and ‘232’ was profiled for volatile compounds over 4 years by headspace solid phase microextraction coupled to gas chromatography and mass spectrometry. More than 300 volatile compounds were detected, of which 87 were identified by comparison of mass spectrum and retention time to those of pure standards. Parental line ‘1392’ displayed higher volatile levels than ‘232’, and these and many other compounds with similar levels in both parents segregated in the progeny. Cluster analysis grouped the volatiles into distinct chemically related families and revealed a complex metabolic network underlying volatile production in strawberry fruit. Quantitative trait loci (QTL) detection was carried out over 3 years based on a double pseudo-testcross strategy. Seventy QTLs covering 48 different volatiles were detected, with several of them being stable over time and mapped as major QTLs. Loci controlling γ-decalactone and mesifurane content were mapped as qualitative traits. Using a candidate gene approach we have assigned genes that are likely responsible for several of the QTLs. As a proof of concept we show that one homoeolog of the O-methyltransferase gene (FaOMT) is the locus responsible for the natural variation of mesifurane content. Sequence analysis identified 30 bp in the promoter of this FaOMT homoeolog containing putative binding sites for basic/helix-loop-helix, MYB, and BZIP transcription factors. This polymorphism fully cosegregates with both the presence of mesifurane and the high expression of FaOMT during ripening.
Staphylococcal superantigen‐like protein 10 binds to phosphatidylserine and apoptotic cells
Authors: Itoh Saotomo , Yokoyama Ryosuke , Murase Chizuko , Takii Takemasa , Tsuji Tsutomu , Onozaki Kikuo
Published: April 2012

Staphylococcal superantigen‐like proteins (SSLs) are a family of exoproteins that have structural similarities to staphylococcal superantigens. Although SSLs do not have superantigenic activity, some of them have been reported to bind to host immune related molecules and they have been implicated in immune evasion by S. aureus. In this study, we showed that SSL10 is capable of binding to phospholipids. SSL10 bound to phosphatidylserine (PS) containing liposome, but not to phosphatidylcholine liposome. SSL10, but not SSL7, bound to PS containing liposome, suggesting that SSL10 specifically binds to PS. Analysis of PS binding ability among recombinant truncated SSL10 fragments revealed that the β‐barrel in the N‐terminal oligonucleotide/oligosaccharide‐binding (OB)‐fold domain contributes to PS binding capacity. Fluorescein isothiocyanate labeled OB‐fold of SSL10 stained hydrogen peroxide treated Jurkat cells. Annexin V is widely utilized for detection of apoptosis. Unlike annexin V, the OB‐fold domain of SSL10 also bound to apoptotic cells in the presence of EDTA, suggesting that the OB‐fold of SSL10 recognizes PS and apoptotic cells in a Ca2+ independent manner. These findings suggest SSL10 and its derived peptides may be a novel detection tool for apoptotic cells.
Development of an in vitro antigen‐detection test as an alternative method to the in vivo plaque reduction neutralization test for the quality control of Japanese encephalitis virus vaccine
Authors: Kim Do Keun , Kim Hye‐Youn , Kim Joo‐Young , Ye Michael B. , Park Kee‐Bum , Han Euiri , Kim Jaeok , Ja Ban Sang , Hong Seung Hwa , Park Yong Keun , Nam Jae‐Hwan
Published: April 2012

Japanese encephalitis virus (JEV) causes diseases that attack the human central nervous system. Traditionally, the quality control for JEV vaccines, in which the plaque reduction neutralization (PRN) titer is measured by the national control laboratories before the vaccine batches are marketed, has required laboratory animal testing. However, classical animal tests have inherent problems, including the very fact that animals are used, ethical issues, and the possibility of error. In this study, JEV antigen was measured in an in vitro assay to assess the feasibility of replacing in vivo assays that measure the PRN titers of JEV vaccines. We constructed a double‐sandwich enzyme‐linked immunosorbent assay (DS‐ELISA) that could detect JEV envelope (E). Initially, monoclonal antibodies (mAbs) directed against the JEV E protein were generated and characterized. We isolated 18 mAbs against JEV E protein, and most were the IgG1 or IgG2a isotype. The mAbs (5F15 and 7D71) were selected as the most suitable mAb pair to detect JEV E protein. DS‐ELISA with this pair detected as little as approximately 3 μg/mL JEV E protein and demonstrated a relationship between the amount of JEV E protein and the PRN titer. From these results, we surmise that this DS‐ELISA may be useful, not only in terms of measuring the amount of JEV E protein, but also as a substitute for the PRN test for JEV vaccine evaluation.
Incorporating multi‐family days into parenting assessments: the Writtle Wick model
Authors: Barratt Sara
Published: April 2012

This paper describes a project undertaken by family centre staff, drawing on the ideas of the Marlborough Family Service in using multi‐family groups as part of their parenting assessments. Child protection assessments are complex and have a far reaching effect on the lives of vulnerable children; practitioners can carry the burden of assessing parents' capacities to meet their children's needs without adequate supervision or support. Our project was developed following the implementation of a new policy, the Public Law Outline, requiring parenting assessments to be completed within a 40‐week time frame. We were concerned that this would not afford the opportunity to develop a sufficient relationship with families to provide a thorough assessment. The paper describes the incorporation of multi‐family days into the parenting assessments and the effect of this work on clients and practitioners. This paper is a practice paper, rather than a formal evaluation, and describes a project in which family centre workers sought to provide a model of assessment based on working as part of a team, managing uncertainty and valuing the opportunity to develop a relationship with clients in order to make an assessment.
Alteration of CD1 expression in multiple sclerosis
Authors: Bine S , Haziot A , Malikova I , Pelletier J , Charron D , Boucraut J , Mooney N , Gelin C
Published: April 2012

Studies of multiple sclerosis (MS) have concentrated mainly on antigen presentation of peptides derived from the myelin sheath, while the implication of lipid antigen has been less explored in this pathology. As the extracellular environment regulates expression of the lipid antigen-presenting molecule CD1, we have examined whether sera from patients alters CD1 surface expression in monocyte-derived dendritic cells. We have shown that: (i) CD1 group 1 proteins were highly expressed in the presence of MS sera; (ii) sera from MS patients differentially regulated CD1 group 1 versus CD1 group 2 molecular expression; and (iii) CD1 was expressed strongly in monocytes from MS patients under immunosuppressive treatment. Overall, these results reveal that CD1 expression is modified in MS and provide novel information on the regulation of lipid antigen presentation in myeloid cells.
Using coupled fish behavior–hydrodynamic model to investigate spawning migration of Japanese anchovy, Engraulis japonicus, from the East China Sea to Taiwan
Authors: TU CHEN‐YI , TSENG YU‐HENG , CHIU TAI‐SHENG , SHEN MAO‐LIN , HSIEH CHIH‐HAO
Published: April 2012

Adult Japanese anchovies (Engraulis japonicus) migrate from the East China Sea to the coastal region of Taiwan to spawn around late winter and early spring and, later, their larvae constitute important fisheries in Taiwan. However, their migration route and its mechanism remain unclear. To investigate their spawning migration, we used a coupled fish behavior–hydrodynamic modeling approach. The physical field is simulated by the Pacific Ocean adaptation of the TaIwan Multi‐scale Community Ocean Model (TIMCOM) and the fish migration by Lagrangian tracer tracking with the aid of approximation of fish swimming behavior. We investigated three fish behavioral scenarios: (i) passive tracking of the current, (ii) swimming along with the current, and (iii) swimming along with the current and then changing to swimming toward the optimal spawning temperature. The comparison with and without Changjiang discharge is used to investigate the impacts of discharge reduction due to the Three Gorges Dam. Our results suggest that spawning migration of Japanese anchovy from the East China Sea to Taiwan may be aided by the China Coastal Current and that adult anchovies cannot reach the spawning site by passive advection alone. Thus, the swimming behavior of anchovies is crucial during the spawning migration, as it provides extra velocity and the orientation to the favorable spawning grounds. In addition, the adult anchovy is unlikely to reach the coastal area of Taiwan without Changjiang discharge. Our findings indicate that a coupled fish behavior–hydrodynamic model can help understand the influences of physical environment on the migration of Japanese anchovies.
RNA plasticity and selectivity applicable to therapeutics and novel biosensor development
Authors: Nakamura Yoshikazu , Ishiguro Akira , Miyakawa Shin
Published: April 2012

Aptamers are short, single‐stranded nucleic acid sequences that are selected in vitro from large oligonucleotide libraries based on their high affinity to a target molecule. Hence, aptamers can be thought of as a nucleic acid analog to antibodies. However, several viewpoints hold that the potential of aptamers arises from interesting characteristics that are distinct from, or in some cases, superior to those of antibodies. This review summarizes the recent achievements in aptamer programs developed in our laboratory against basic and therapeutic protein targets. Through these studies, we became aware of the remarkable conformational plasticity and selectivity of RNA, on which the published report has not shed much light even though this is evidently a crucial feature for the strong specificity and affinity of RNA aptamers.
The incidence of human herpes virus‐8 expression in lymph node biopsies from human immunodeficiency virus‐positive patients
Authors: Beukes Catherine A , Thiart Jacoretha
Published: April 2012

Beukes C A & Thiart J  (2012) Histopathology 61, 942–944

The incidence of human herpes virus‐8 expression in lymph node biopsies from human immunodeficiency virus‐positive patients

Aims:  Human immunodeficiency virus (HIV)‐related lymphadenopathy is characterized by a wide spectrum of histological changes. Three patterns have been described which correspond to clinical stages of HIV/acquired immune deficiency syndrome (AIDS). Castleman disease is a heterogeneous group of disorders. A recently described variant, multicentric Castleman disease (MCD), of which some cases are associated with human herpes virus‐8 (HHV‐8), has been reported in both HIV‐seropositive and ‐negative patients. Considerable morphological overlap occurs between one of the patterns of HIV lymphadenopathy and this variant.

Methods and results:  This retrospective histopathological study on 95 cases of HIV‐reactive lymphadenopathy assessed the incidence of the different patterns and HHV‐8 on immunohistochemistry (IHC). Of the 95 cases, 78 (82.1%) were HHV‐8‐negative, of which 46 (59.0%) were classified as pattern A, 20 (25.6%) as pattern B and 12 (15.4%) as pattern C. Nine (31.0%) of 29 cases with pattern B and 8 (40.0%) of 20 cases with pattern C were HHV‐8 positive. In total 15 cases of MCD were diagnosed in this series.

Conclusion:  This study draws attention to the overlap between HIV lymphadenopathy and MCD. We recommend that cases of HHV‐8‐associated MCD should be investigated for HIV infection.
A comparative study on the antioxidative and anti‐allergic activities of fresh and aged black garlic extracts
Authors: Kim Joo Hee , Nam Seok Hyun , Rico Catherine W. , Kang Mi Young
Published: April 2012

The antioxidative and anti‐allergic activities of fresh and aged black garlic extracts were investigated. The garlic samples were extracted with 70% ethanol (v/v) and the total phenolic content was measured. The antioxidant capacity of extracts was assessed by determining the scavenging activities on 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals, ferricyanide reducing power, ferrous ion‐chelating ability and inhibitory effect on linoleic acid peroxidation. The anti‐allergic activity of extracts was analysed by measuring their inhibitory effects against β‐hexosaminidase release. The aged black garlic exhibited significantly higher phenolic content and greater antioxidative activity than fresh garlic. Both garlic extracts showed strong antioxidant capacity in a dose‐dependent manner. On the other hand, a considerably higher suppression of β‐hexosaminidase release was found in fresh garlic extract at lower concentration compared with that of the black garlic. Results of this study illustrate that ageing of garlic could enhance its antioxidant capacity, but could decrease its anti‐allergic activity.