bluuebunny/crossref_metadata_2025 huggingface dataset:
Liquid-liquid phase transformations and the shape of the melting curve
Authors: Makov G. , Yahel E.
Published: May 2011

The phase diagram of elemental liquids has been found to be surprisingly rich, including variations in the melting curve and transitions in the liquid phase. The effect of these transitions in the liquid state on the shape of the melting curve is analyzed. First-order phase transitions intersecting the melting curve imply piecewise continuous melting curves, with solid-solid transitions generating upward kinks or minima and liquid-liquid transitions generating downward kinks or maxima. For liquid-liquid phase transitions proposed for carbon, phosphorous selenium, and possibly nitrogen, we find that the melting curve exhibits a kink. Continuous transitions imply smooth extrema in the melting curve, the curvature of which is described by an exact thermodynamic relation. This expression indicates that a minimum in the melting curve requires the solid compressibility to be greater than that of the liquid, a very unusual situation. This relation is employed to predict the loci of smooth maxima at negative pressures for liquids with anomalous melting curves. The relation between the location of the melting curve maximum and the two-state model of continuous liquid-liquid transitions is discussed and illustrated by the case of tellurium.
Observation of anomalous acoustic phonon dispersion in SrTiO3 by broadband stimulated Brillouin scattering
Authors: Brivio S. , Polli D. , Crespi A. , Osellame R. , Cerullo G. , Bertacco R.
Published: May 2011

Femtosecond laser pulses have been used to generate and detect longitudinal acoustic phonons along the [001] direction of SrTiO3 single crystals coated with a thin absorbing layer. Two-dimensional maps of the reflectivity as a function of probe wavelength and time delay display persistent oscillations, from which the frequency-dependent group velocity of the photoinduced strain pulse can be directly measured. By applying the theory of stimulated Brillouin scattering we found that the longitudinal sound speed varies from 7900 to 7520 m/s in the 60–74 rad μm−1 wave vector range, thus indicating a clear deviation from a linear phonon dispersion relationship.
Distributed feedback quantum cascade lasers at 13.8 μm on indium phosphide
Authors: Fuchs Peter , Semmel Julia , Friedl Jochen , Höfling Sven , Koeth Johannes , Worschech Lukas , Forchel Alfred
Published: May 2011

We report on the growth, processing, and characterization of distributed feedback quantum cascade lasers emitting in single mode at 13.8 μm. Lasers were grown in the indium phosphide material system with a bound-to-continuum active region and processed as double channel ridges with metalized top grating. Electro-optic characteristics as well as current and temperature tuning are investigated. Maximum single mode peak powers exceeding 800 mW at room temperature and intrapulse-tuning covering 3 cm−1 for a gas absorption experiment are demonstrated. Furthermore data on the far field are presented showing a slow-axis divergence angle of 28.3° (full width at half maximum).
Impact of intramolecular twisting and exciton migration on emission efficiency of multifunctional fluorene-benzothiadiazole-carbazole compounds
Authors: Karpicz R. , Puzinas S. , Krotkus S. , Kazlauskas K. , Jursenas S. , Grazulevicius J. V. , Grigalevicius S. , Gulbinas V.
Published: May 2011

Novel donor-acceptor compounds consisting of singly bonded fluorene (Fl), benzothiadiazole (BT), and carbazole (Cz) functional units in the same molecule were investigated. Analysis of the optical spectra and fluorescence transients of the compounds revealed the domination of intramolecular charge transfer (ICT) states with high fluorescence quantum yield (72%–85%). A similar Cz-Fl-Cz compound exhibiting 100% fluorescence quantum yield and no ICT character was also studied as a reference to reveal the impact of electron-accepting BT groups. Thorough examination of the optical properties of the compounds in different media, i.e., dilute solution and polymer matrix, indicated their twisted conformations due to steric hindrance in the ground state and flattened geometry in the excited state for both reference and ICT compounds. Remarkable fluorescence efficiency losses (amounting to 70%) observed upon casting the molecular solutions into neat films were determined to originate from the low-fluorescent twisted conformers and migration-facilitated exciton quenching. The majority of emission efficiency losses (over 70%) were caused by the twisted conformers, whereas only less than 30% by exciton-migration-induced nonradiative deactivation.
Electronic coupling calculation and pathway analysis of electron transfer reaction using ab initio fragment-based method. I. FMO–LCMO approach
Authors: Nishioka Hirotaka , Ando Koji
Published: May 2011

By making use of an ab initio fragment-based electronic structure method, fragment molecular orbital–linear combination of MOs of the fragments (FMO–LCMO), developed by Tsuneyuki et al. [Chem. Phys. Lett. 476, 104 (2009)]10.1016/j.cplett.2009.05.069, we propose a novel approach to describe long-distance electron transfer (ET) in large system. The FMO–LCMO method produces one-electron Hamiltonian of whole system using the output of the FMO calculation with computational cost much lower than conventional all-electron calculations. Diagonalizing the FMO–LCMO Hamiltonian matrix, the molecular orbitals (MOs) of the whole system can be described by the LCMOs. In our approach, electronic coupling TDA of ET is calculated from the energy splitting of the frontier MOs of whole system or perturbation method in terms of the FMO–LCMO Hamiltonian matrix. Moreover, taking into account only the valence MOs of the fragments, we can considerably reduce computational cost to evaluate TDA. Our approach was tested on four different kinds of model ET systems with non-covalent stacks of methane, non-covalent stacks of benzene, trans-alkanes, and alanine polypeptides as their bridge molecules, respectively. As a result, it reproduced reasonable TDA for all cases compared to the reference all-electron calculations. Furthermore, the tunneling pathway at fragment-based resolution was obtained from the tunneling current method with the FMO–LCMO Hamiltonian matrix.
Electron scattering in Pt(PF3)4: Elastic scattering, vibrational, and electronic excitation
Authors: Allan M.
Published: May 2011

Experimental absolute differential cross sections for elastic scattering, and for vibrational and electronic excitation of Pt(PF3)4 by low-energy electrons are presented. The elastic cross sections have a deep angle-dependent Ramsauer-Townsend minimum (Emin = 0.26 eV at θ = 135°). The angular distributions of the elastic cross section at and above 6.5 eV show an unusually narrow peak at an angle which decreases with increasing energy (it is at 40° at 20 eV). Wavy structure is observed at higher angles at 15 and 20 eV. Vibrational excitation cross sections reveal five shape resonances, at 0.84, 1.75, 3.3, 6.6, and 8.5 eV. The angular distributions of the vibrational cross sections have a strong forward peak and are nearly isotropic above about 60°. Electronically excited states are characterized by electron energy-loss spectra. They show a number of unstructured bands, the lowest at 5.8 eV. They are assigned to Rydberg states converging to the 1st and 2nd ionization energies. The cross sections for electronic excitation have very high forward peaks, reaching the value of 50 Å2 at 50 eV and 0° scattering angle. Purity of the sample was monitored by the very low frequency (26 meV) Pt−P stretch vibration in the energy-loss spectra.
Nonvolatile low-voltage memory transistor based on SiO2 tunneling and HfO2 blocking layers with charge storage in Au nanocrystals
Authors: Mikhelashvili V. , Meyler B. , Yofis S. , Shneider Y. , Zeidler A. , Garbrecht M. , Cohen-Hyams T. , Kaplan W. D. , Lisiansky M. , Roizin Y. , Salzman J. , Eisenstein G.
Published: May 2011

We demonstrate a low voltage nonvolatile memory field effect transistor comprising thermal SiO2 tunneling and HfO2 blocking layers as the gate dielectric stack and Au nanocrystals as charge storage nodes. The structure exhibits a memory window of ∼2 V at an applied sweeping voltage of ±3 V which increases to 12.6 at ±12 V. Retention tests show an extrapolated loss of 16% after ten years in the hysteresis width of the threshold voltage. Dynamic program/erase operation reveal an approximately pulse width independent memory for pulse durations of 1 μs to 10 ms; longer pulses increase the memory window while for pulses shorter than 1 μs, the memory windows vanishes. The effective oxide thickness is below 10 nm with very low gate and drain leakage currents.
Are Visual Cue Masking and Removal Techniques Equivalent for Studying Perceptual Skills in Sport?
Authors: Mecheri Sami , Gillet Eric , Thouvarecq Régis , Leroy David
Published: May 2011

The spatial-occlusion paradigm makes use of two techniques (masking and removing visual cues) to provide information about the anticipatory cues used by viewers. The visual scene resulting from the removal technique appears to be incongruous, but the assumed equivalence of these two techniques is spreading. The present study was designed to address this issue by combining eye-movement recording with the two types of occlusion (removal versus masking) in a tennis serve – return task. Response accuracy and decision onsets were analysed. The results indicated that subjects had longer reaction times under the removal condition, with an identical proportion of correct responses. Also, the removal technique caused the subjects to rely on atypical search patterns. Our findings suggest that, when the removal technique was used, viewers were unable to systematically count on stored memories to help them accomplish the interception task. The persistent failure to question some of the assumptions about the removal technique in applied visual research is highlighted, and suggestions for continued use of the masking technique are advanced.
Finding a Face in a Face-like Object
Authors: Ichikawa Hiroko , Kanazawa So , Yamaguchi Masami K
Published: May 2011

Humans have the tendency to perceive a face even in a non-living object. Previous studies report that people perceive facial features and even interpret a personality in a car front. Following these findings, we investigated whether the perception of a face in a face-like object is mediated by human face processing, which involves both featural and configural processing. In our experiment, participants were presented with 30 face-like objects and were asked about the existence of facial features, the intensity of typicality/distinctiveness, and the intensity of facial expression. Using multiple regression analysis, which predicts the perception of a face in a face-like object, we found that the existence of eyes was a significant predictor of variance in perceiving a face in a face-like object.
Does rapid scavenging hide non-predation mortality in coral-reef communities?
Authors: Rassweiler Andrew , Rassweiler Thomas
Published: May 2011

Predation is assumed to be a principal cause of adult fish mortality on coral reefs, and therefore a main pathway by which biomass is passed to higher trophic levels. However, the strength of predation has mostly been demonstrated on juvenile fish, and even with juveniles, when predators are excluded, substantial mortality still occurs. Mortality from causes other than predation is rarely considered, because carrion is not common on coral reefs, but the strength of this inference depends crucially on the rate of scavenging. We tested the hypothesis that removal of carrion through scavenging may be very rapid by placing undamaged fish carcasses of a range of species and sizes on reefs in Curaçao, monitoring their rate of disappearance. All carrion was consumed within 24 h and at such rapid rates that, if non-predation mortality were occurring, it would leave little evidence on the reef. Carcasses were consumed almost exclusively by fish, mainly reef-associated piscivores, indicating that scavenged biomass is tightly recycled within the reef fish community. The results of this study suggest that more attention should be paid to quantifying the role of non-predation sources of fish mortality in reef ecosystems.
Alternative mechanism for bacteriophage adsorption to the motile bacterium
Caulobacter crescentus
Authors: Guerrero-Ferreira Ricardo C. , Viollier Patrick H. , Ely Bert , Poindexter Jeanne S. , Georgieva Maria , Jensen Grant J. , Wright Elizabeth R.
Published: May 2011

2D and 3D cryo-electron microscopy, together with adsorption kinetics assays of ϕCb13 and ϕCbK phage-infected
Caulobacter crescentus
, provides insight into the mechanisms of infection. ϕCb13 and ϕCbK actively interact with the flagellum and subsequently attach to receptors on the cell pole. We present evidence that the first interaction of the phage with the bacterial flagellum takes place through a filament on the phage head. This contact with the flagellum facilitates concentration of phage particles around the receptor (i.e., the pilus portals) on the bacterial cell surface, thereby increasing the likelihood of infection. Phage head filaments have not been well characterized and their function is described here. Phage head filaments may systematically underlie the initial interactions of phages with their hosts in other systems and possibly represent a widespread mechanism of efficient phage propagation.
Results from radiating divertor experiments with RMP ELM suppression and mitigation
Authors: Petrie T.W. , Evans T.E. , Brooks N.H. , Fenstermacher M.E. , Ferron J.R. , Holcomb C.T. , Hudson B. , Hyatt A.W. , Luce T.C. , Lasnier C.J. , Mordijck S. , Moyer R.A. , Osborne T.H. , Politzer P.A. , Rensink M.E. , Schaffer M.J. , Snyder P.B. , Watkins J.G.
Published: May 2011

The range in density and collisionality for which resonant magnetic perturbations (RMPs) are effective in suppressing edge-localized modes (ELMs) in the presence of a radiating divertor was found to be modest for representative H-mode plasmas in DIII-D. When deuterium and argon gas injection rates were increased during RMP, both the electron collisionality in the pedestal
and the maximum electron pressure gradient (∇P
e,MAX) in the pedestal also increased. As ∇P
e,MAX approached values consistent with the peeling–ballooning stability limit, as determined by edge stability analysis, ELMing activity re-emerged. For cases with the same injected neutral beam power, argon accumulation in the main plasma was greater in the RMP ELM-suppressed cases than in comparable non-RMP ELMing H-mode cases. Reductions in the core concentration of injected argon were observed for both RMP and non-RMP H-mode cases when their respective deuterium injection rates were increased. Although complete ELM suppression in RMP radiating divertor plasmas in DIII-D was only accessible over a limited range in pedestal density and collisionality, significant ELM mitigation with heat flux reduction was possible over a wider range. Comparing RMP radiating divertor discharges after the re-appearance of ELMing activity during gas puffing with a standard ELMing plasma for cases with the same pedestal density reveals that the RMP discharges have (1) lower average electron temperature at the midplane separatrix, implying lower average electron temperature at the divertor target, (2) lower time-averaged peak heat flux and (3) lower transient peak heat flux from ELMs even at the same pedestal collisionality.
Magnetic energy flows during the current quench and termination of disruptions with runaway current plateau formation in JET and implications for ITER
Authors: Loarte A. , Riccardo V. , Martin-Solís J.R. , Paley J. , Huber A. , Lehnen M.
Published: May 2011

The magnetic energy balance and magnetic energy flows for plasma disruptions in which runaway plateau plasmas are formed and terminated at JET has been analysed and compared with that of runaway-free disruptions. The analysis shows that the energy loss processes during runaway plateau plasma termination are qualitatively different from those of a runaway-free disruption because of the pre-existence of a runaway population in the first case. As a consequence, a significant fraction of the runaway plateau plasma magnetic energy is directly converted into runaway electron kinetic energy during the runaway plateau termination phase. This leads to the fluxes being deposited by runaway electrons onto in-vessel components during the termination of runaway plateaus to be significantly larger than those expected from the initial kinetic energy of the runaway electrons in the runaway plateau plasma.
Effect of a magnetic island on the three-dimensional structure of edge radiation and its consequences on detachment in the Large Helical Device (EX-D)
Authors: Drapiko E.A. , Peterson B.J. , Kobayashi M. , Masuzaki S. , Morisaki T. , Shoji M. , Tokitani M. , Tamura N. , Morita S. , Goto M. , Yoshimura S. , Miyazawa J. , Ashikawa N. , Seo D.C. , Yamada H.
Published: May 2011

In this paper the effects of an externally produced magnetic island (MI) on the 3D radiation structure in attached and detached plasmas as predicted by the EMC3-EIRENE code are clearly seen in the imaging bolometer (IRVB) data from two different views of the plasma, experimentally confirming the role that the MI plays in the detachment process. With the addition of the MI the carbon radiation profile from the code in a poloidal cross-section becomes more localized near the helical divertor x-points (HDXs). This is reflected in the focusing of the radiation patterns corresponding to the HDX in both the IRVB and code data in images corresponding to the IRVB field of view (FOV). Detachment results in a more asymmetric radiation profile in the poloidal cross-section code data with localized peaks near the HDX and magnetic island x-points (MIXs). The radiation from the MIXs is reflected in strong radiation from the corresponding location in the IRVB FOV from both code and IRVB data. Also the change in the position of the MI results in a change in the position of the localized radiation peak as predicted by the code. However, the relative increase in the radiation from the MIXs is greater in the code data than in the IRVB data for reasons which are so far unknown. Also similar discharges show detachment with the MI, albeit at a lower density than the discharge without the MI. This work confirms the previous conclusions that the MI enhances the localization of the radiation and is conducive to achieving and sustaining the detachment.
On the crossing numbers of a virtual knot
Authors: Satoh Shin , Tomiyama Yumi
Published: May 2011

We give lower bounds of the real crossing number of a virtual knot in terms of the Jones polynomial and the Miyazawa polynomial. As an application, we prove the existence of a virtual knot such that the real and virtual crossing numbers are equal to

m
m

and

n
n

for any positive integers

m
>
n

m>n

.
Hierarchical regulation of mRNA partitioning between the cytoplasm and the endoplasmic reticulum of mammalian cells
Authors: Chen Qiang , Jagannathan Sujatha , Reid David W. , Zheng Tianli , Nicchitta Christopher V.
Published: May 2011

The mRNA transcriptome is currently thought to be partitioned between the cytosol and endoplasmic reticulum (ER) compartments by binary selection; mRNAs encoding cytosolic/nucleoplasmic proteins are translated on free ribosomes, and mRNAs encoding topogenic signal-bearing proteins are translated on ER-bound ribosomes, with ER localization being conferred by the signal-recognition particle pathway. In subgenomic and genomic analyses of subcellular mRNA partitioning, we report an overlapping subcellular distribution of cytosolic/nucleoplasmic and topogenic signal-encoding mRNAs, with mRNAs of both cohorts displaying noncanonical subcellular partitioning patterns. Unexpectedly, the topogenic signal-encoding mRNA transcriptome was observed to partition in a hierarchical, cohort-specific manner. mRNAs encoding resident proteins of the endomembrane system were clustered at high ER-enrichment values, whereas mRNAs encoding secretory pathway cargo were broadly represented on free and ER-bound ribosomes. Two distinct modes of mRNA association with the ER were identified. mRNAs encoding endomembrane-resident proteins were bound via direct, ribosome-independent interactions, whereas mRNAs encoding secretory cargo displayed predominantly ribosome-dependent modes of ER association. These data indicate that mRNAs are partitioned between the cytosol and ER compartments via a hierarchical system of intrinsic and encoded topogenic signals and identify mRNA cohort-restricted modes of mRNA association with the ER.
Caenorhabditis elegansSNAP-29 is required for organellar integrity of the endomembrane system and general exocytosis in intestinal epithelial cells
Authors: Sato Miyuki , Saegusa Keiko , Sato Katsuya , Hara Taichi , Harada Akihiro , Sato Ken
Published: May 2011

It is generally accepted that soluble N-ethylmaleimide–sensitive factor attachment protein receptors mediate the docking and fusion of transport intermediates with target membranes. Our research identifies Caenorhabditis elegans homologue of synaptosomal-associated protein 29 (SNAP-29) as an essential regulator of membrane trafficking in polarized intestinal cells of living animals. We show that a depletion of SNAP-29 blocks yolk secretion and targeting of apical and basolateral plasma membrane proteins in the intestinal cells and results in a strong accumulation of small cargo-containing vesicles. The loss of SNAP-29 also blocks the transport of yolk receptor RME-2 to the plasma membrane in nonpolarized oocytes, indicating that its function is required in various cell types. SNAP-29 is essential for embryogenesis, animal growth, and viability. Functional fluorescent protein–tagged SNAP-29 mainly localizes to the plasma membrane and the late Golgi, although it also partially colocalizes with endosomal proteins. The loss of SNAP-29 leads to the vesiculation/fragmentation of the Golgi and endosomes, suggesting that SNAP-29 is involved in multiple transport pathways between the exocytic and endocytic organelles. These observations also suggest that organelles comprising the endomembrane system are highly dynamic structures based on the balance between membrane budding and fusion and that SNAP-29–mediated fusion is required to maintain proper organellar morphology and functions.
Role of Type IV Pili in Virulence of Pseudomonas syringae pv. tabaci 6605: Correlation of Motility, Multidrug Resistance, and HR-Inducing Activity on a Nonhost Plant
Authors: Taguchi Fumiko , Ichinose Yuki
Published: May 2011

To investigate the role of type IV pili in the virulence of phytopathogenic bacteria, four mutant strains for pilus biogenesis-related genes were generated in Pseudomonas syringae pv. tabaci 6605. PilA encodes the pilin protein as a major subunit of type IV pili, and the pilO product is reported to be required for pilus assembly. The fimU and fimT genes are predicted to produce minor pilins. Western blot analysis revealed that pilA, pilO, and fimU mutants but not the fimT mutant failed to construct type IV pili. Although the swimming motility of all mutant strains was not impaired in liquid medium, they showed remarkably reduced motilities on semisolid agar medium, suggesting that type IV pili are required for surface motilities. Virulence toward host tobacco plants and hypersensitive response-inducing ability in nonhost Arabidopsis leaves of pilA, pilO, and fimU mutant strains were reduced. These results might be a consequence of reduced expression of type III secretion system-related genes in the mutant strains. Further, all mutant strains showed enhanced expression of resistance-nodulation-division family members mexA, mexB, and oprM, and higher tolerance to antimicrobial compounds. These results indicate that type IV pili are an important virulence factor of this pathogen.
A Novel Regulatory Role of HrpD6 in Regulating hrp-hrc-hpa Genes in Xanthomonas oryzae pv. oryzicola
Authors: Li Yu-Rong , Zou Hua-Song , Che Yi-Zhou , Cui Yi-Ping , Guo Wei , Zou Li-Fang , Chatterjee Subhadeep , Biddle Eulandria M. , Yang Ching-Hong , Chen Gong-You
Published: May 2011

Xanthomonas oryzae pv. oryzicola, the causal agent of bacterial leaf streak in the model plant rice, possesses a hypersensitive response and pathogenicity (hrp), hrp-conserved (hrc), hrp-associated (hpa) cluster (hrp-hrc-hpa) that encodes a type III secretion system (T3SS) through which T3SS effectors are injected into host cells to cause disease or trigger plant defenses. Mutations in this cluster usually abolish the bacterial ability to cause hypersensitive response in nonhost tobacco and pathogenicity in host rice. In Xanthomonas spp., these genes are generally assumed to be regulated by the key master regulators HrpG and HrpX. However, we present evidence that, apart from HrpG and HrpX, HrpD6 is also involved in regulating the expression of hrp genes. Interestingly, the expression of hpa2, hpa1, hpaB, hrcC, and hrcT is positively controlled by HrpD6. Transcriptional expression assays demonstrated that the expression of the hrcC, hrpD5, hrpE, and hpa3 genes was not completely abolished by hrpG and hrpX mutations. As observed in analysis of their corresponding mutants, HrpG and HrpX exhibit contrasting gene regulation, particularly for hpa2 and hrcT. Other two-component system regulators (Zur, LrpX, ColR/S, and Trh) did not completely inhibit the expression of hrcC, hrpD5, hrpE, and hpa3. Immunoblotting assays showed that the secretion of HrpF, which is an HpaB-independent translocator, is not affected by the mutation in hrpD6. However, the mutation in hrpD6 affects the secretion of an HpaB-dependent TAL effector, AvrXa27. These novel findings suggest that, apart from HrpG and HrpX, HrpD6 plays important roles not only in the regulation of hrp genes but also in the secretion of TAL effectors.
Occurrence of Downy Mildew Caused by Peronospora belbahrii on Sweet Basil in Hungary
Authors: Nagy G. , Horváth A.
Published: May 2011

Sweet basil (Ocimum basilicum L.) is an important medicinal and aromatic plant in Hungary that is cultivated over a large area. During field surveys conducted in 2010, significant incidence of downy mildew was observed in two plant stands at Budapest-Soroksár and Tordas. In 2003, the disease occurred in a greenhouse at Albertirsa as well. By the end of September, on full-grown leaves of two sweet basil cultivars, the frequency of disease occurrence and the percentage of infected leaf area reached 80 to 90% and 17 to 20%, respectively, at Budapest-Soroksár. Symptoms appeared mainly on cvs. Genovese and Milita among others. On leaves, large chlorotic lesions with soft margins developed, followed by necrotization from the middle. Chlorosis often involved the entire leaf surface. Necrotic spots were irregular, variable in diameter, and limited by the main veins. A typical grayish white furry growth could be observed mainly on abaxial leaf surfaces both in chlorotic and necrotic regions. Most abundant growth developed on the leaves of cv. Genovese. Premature leaf fall on diseased plants occurred as well. The fungus was identified as Peronospora belbahrii Thines on the basis of morphological investigation suggested by Thines et al. (4). Sporangiophores were colorless with a long, straight trunk and monopodially branched five to seven times with a length of 416 to 784 μm (average 572 μm). Sporangiophores ended with two slightly curved acute branchlets, the longer one measured 12.5 to 25.0 μm (average 17.1 μm) and the shorter one measured 5.0 to 18.8 μm (average 9.5 μm) long. Ratio of longer to shorter branchlets was 0.7 to 3.0, the average ratio was 1.9. Sporangia were rounded or slightly ovoid, olive to dark brown, and measured 29.3 × 25.6 (23.8 to35.0 × 20.0 to 31.3 μm). Length/width ratio was 1.2 (1.0 to 1.4). Molecular investigation of two isolates was performed. DNA extraction from sporangiophores was followed by PCR using ITS5 and ITS4 primers. The obtained sequence (GenBank Accession No. HQ702191) showed 99.8 to 100.0% similarity with sequences of P. belbahrii (e.g., Accession Nos. FJ394335 and HN462241) and Peronospora sp. (e.g., Accession Nos. AY884605, AY919301, and FJ346561) isolated from sweet basil. In Europe, the disease was reported from Italy (2), France (3), Germany (4), and Switzerland (1). To our knowledge, this is the first report of downy mildew on sweet basil in Hungary.

References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) A. Garibaldi et al. Plant Dis. 88:312, 2004. (3) A. Garibaldi et al. Plant Dis. 89:683, 2005. (4) M. Thines et al. Mycol. Res. 113:532, 2009.
Anorectal Manometry May Identify Children With Spinal Cord Lesions
Authors: Siddiqui Anees , Rosen Rachel , Nurko Samuel
Published: May 2011

Background and Objective:

We previously showed that approximately 10% of patients with intractable constipation have spinal abnormalities without any other physical findings. Given that spinal magnetic resonance imaging is costly and often requires deep sedation in children, it would be useful to find a screening tool to determine who has a higher likelihood of having a spinal abnormality. The aim of the study was to determine whether anorectal manometry is a useful screening test in predicting which patients will have abnormal spinal MRIs.

Patients and Methods:

This is a case‐control study comparing the anorectal manometries of 10 children with constipation who had abnormal spinal MRIs (cases) to the manometries of 10 age‐matched children with normal MRIs (controls).

Results:

The maximum relaxation of the sphincter after balloon distention was achieved with a significantly smaller balloon in the cases as compared with the controls (35 ± 20 vs 60 ± 23 mL; P = 0.02). The dose‐response curve of sphincter relaxation at different balloon distention was shifted to the left in patients with spinal lesions. Anal spasms after balloon distention were noted in 60% of the patients with abnormal magnetic resonance images compared with 0% of the controls (P < 0.003). There were no other differences.

Conclusions:

Patients with spinal cord abnormalities may show changes in anorectal manometry. Anal spasms on anorectal manometry are significant predictors of spinal abnormalities. Also, patients with spinal abnormalities have maximum sphincter relaxations with smaller balloon sizes. Further studies are needed to determine the utility of anorectal manometry as a screening test for spinal abnormalities in patients with constipation.
System among the corticosteroids: specificity and molecular dynamics
Authors: Brookes Jennifer C. , Galigniana Mario D. , Harker Anthony H. , Stoneham A. Marshall , Vinson Gavin P.
Published: May 2011

Understanding how structural features determine specific biological activities has often proved elusive. With over 161 000 steroid structures described, an algorithm able to predict activity from structural attributes would provide manifest benefits. Molecular simulations of a range of 35 corticosteroids show striking correlations between conformational mobility and biological specificity. Thus steroid ring A is important for glucocorticoid action, and is rigid in the most specific (and potent) examples, such as dexamethasone. By contrast, ring C conformation is important for the mineralocorticoids, and is rigid in aldosterone. Other steroids that are less specific, or have mixed functions, or none at all, are more flexible. One unexpected example is 11-deoxycorticosterone, which the methods predict (and our activity studies confirm) is not only a specific mineralocorticoid, but also has significant glucocorticoid activity. These methods may guide the design of new corticosteroid agonists and antagonists. They will also have application in other examples of ligand–receptor interactions.
In situ
preparation and protein delivery of silicate–alginate composite microspheres with core-shell structure
Authors: Wu Chengtie , Fan Wei , Gelinsky Michael , Xiao Yin , Chang Jiang , Friis Thor , Cuniberti Gianaurelio
Published: May 2011

The efficient loading and sustained release of proteins from bioactive microspheres remain a significant challenge. In this study, we have developed bioactive microspheres which can be loaded with protein and then have a controlled rate of protein release into a surrounding medium. This was achieved by preparing a bioactive microsphere system with core-shell structure, combining a calcium silicate (CS) shell with an alginate (A) core by a one-step
in situ
method. The result was to improve the microspheres' protein adsorption and release, which yielded a highly bioactive material with potential uses in bone repair applications. The composition and the core-shell structure, as well as the formation mechanism of the obtained CS–A microspheres, were investigated by X-ray diffraction, optical microscopy, scanning electron microscopy, energy dispersive spectrometer dot and line-scanning analysis. The protein loading efficiency reached 75 per cent in CS–A microspheres with a core-shell structure by the
in situ
method. This is significantly higher than that of pure A or CS–A microspheres prepared by non-
in situ
method, which lack a core-shell structure. CS–A microspheres with a core-shell structure showed a significant decrease in the burst release of proteins, maintaining sustained release profile in phosphate-buffered saline (PBS) at both pH 7.4 and 4.3, compared with the controls. The protein release from CS–A microspheres is predominantly controlled by a Fickian diffusion mechanism. The CS–A microspheres with a core-shell structure were shown to have improved apatite-mineralization in simulated body fluids compared with the controls, most probably owing to the existence of bioactive CS shell on the surface of the microspheres. Our results indicate that the core-shell structure of CS–A microspheres play an important role in enhancing protein delivery and mineralization, which makes these composite materials promising candidates for application in bone tissue regeneration.
Whole-genome analysis reveals the complex evolutionary dynamics of Kenyan G2P[4] human rotavirus strains
Authors: Ghosh Souvik , Adachi Noriaki , Gatheru Zipporah , Nyangao James , Yamamoto Dai , Ishino Masaho , Urushibara Noriko , Kobayashi Nobumichi
Published: May 2011

Although G2P[4] rotaviruses are common causes of acute childhood diarrhoea in Africa, to date there are no reports on whole genomic analysis of African G2P[4] strains. In this study, the nearly complete genome sequences of two Kenyan G2P[4] strains, AK26 and D205, detected in 1982 and 1989, respectively, were analysed. Strain D205 exhibited a DS-1-like genotype constellation, whilst strain AK26 appeared to be an intergenogroup reassortant with a Wa-like NSP2 genotype on the DS-1-like genotype constellation. The VP2-4, VP6-7, NSP1, NSP3 and NSP5 genes of strain AK26 and the VP2, VP4, VP7 and NSP1–5 genes of strain D205 were closely related to those of the prototype or other human G2P[4] strains. In contrast, their remaining genes were distantly related, and, except for NSP2 of AK26, appeared to originate from or share a common origin with rotavirus genes of artiodactyl (ruminant and camelid) origin. These observations highlight the complex evolutionary dynamics of African G2P[4] rotaviruses.
Small cell variant of mantle cell lymphoma is an indolent lymphoma characterized by bone marrow involvement, splenomegaly, and a low Ki‐67 index
Authors: Kimura Yoshizo , Sato Kensaku , Imamura Yutaka , Arakawa Fumiko , Kiyasu Junichi , Takeuchi Masanori , Miyoshi Hiroaki , Yoshida Maki , Niino Daisuke , Sugita Yasuo , Morito Toshiaki , Yoshino Tadashi , Nakamura Shigeo , Ohshima Koichi
Published: May 2011

Mantle cell lymphoma (MCL) is recognized as a well‐defined B cell neoplasm characterized by overexpression of cyclin D1 (CCND1), with “classical” and “aggressive” variant subtypes. A small‐cell variant of MCL (small‐MCL), resembling small lymphocytic lymphoma/chronic lymphocytic lymphoma (CLL/SLL), has been added to the World Health Organization classification. However, to the best of our knowledge, there have been no studies focusing on this neoplasm. In the present study, we analyzed 15 cases of CCND1‐positive small‐MCL, including immunohistochemical analysis of Ki‐67 and CCND1 expression, and compared our findings with those of 151 cases of classical MCL. Morphologically, most small‐MCL showed a diffuse growth pattern (76.9%), whereas others featured a very thin mantle zone pattern resembling a reactive follicle (23.1%). Bone marrow involvement and splenomegaly occurred significantly more frequently in small‐MCL than in classical MCL (P < 0.05). Ki‐67 expression in small‐MCL was lower than in classical MCL (mean [±2 SD] 12.5 ± 17.3% and 25.2 ± 25.5%, respectively; P < 0.001), but there was no significant difference in CCND1 expression (P = 0.2445). The 5‐year survival rate in small‐MCL was 83.3%. Although there was no significant difference in outcome between small‐MCL and classical MCL (P = 0.287), only one small‐MCL patient died of the disease. Thus, small‐MCL constitutes a specific subset of indolent lymphoma with distinguishing features, possibly making a major contribution to the accuracy of therapeutic decisions. In addition, clinicians should be aware of the possible presence of small‐MCL to avoid making a misdiagnosis of follicular hyperplasia or CLL/SLL. (Cancer Sci 2011; 102: 1734–1741)
Nurse‐like cells show deregulated expression of genes involved in immunocompetence
Authors: Bhattacharya Nupur , Diener Susanne , Idler Irina S. , Rauen Judith , Häbe Sarah , Busch Hauke , Habermann Annett , Zenz Thorsten , Döhner Hartmut , Stilgenbauer Stephan , Mertens Daniel
Published: May 2011

Chronic lymphocytic leukaemia (CLL) cells convert CD14+ cells from patients into ‘nurse‐like’ cells (NLCs). CLL cells can also convert CD14+ peripheral blood mononuclear cells (PBMCs) from healthy donors into cells with morphological similarities to NLCs (CD14CLL‐cells). However it is unclear whether only CLL cells induce this conversion process. This study showed that CD14+ PBMCs from healthy donors could also be converted into differentiated cells (CD14B‐cells) by non‐malignant B‐cells. In order to identify changes specifically induced by CLL cells, we compared gene expression profiles of NLCs, CD14CLL‐cells and CD14B‐cells. CD14+ cells cultured with CLL cells were more similar to NLCs than those cultured with non‐malignant B‐cells. The most significant changes induced by CLL cells were deregulation of the antigen presentation pathway and of genes related to immunity. NLCs had reduced levels of lysozyme activity, CD74 and HLA‐DR in‐vitro while expression of inhibitory FCGR2B was increased. These findings suggest an impaired immunocompetence of NLCs which, if found in‐vivo, could contribute to the immunodeficiency in CLL patients.
Genomic gain and over expression of CCL2 correlate with vascular invasion in stage I non‐seminomatous testicular germ‐cell tumours
Authors: Gilbert D. C. , Chandler I. , Summersgill B. , McIntyre A. , Missiaglia E. , Goddard N. C. , Huddart R. A. , Shipley J.
Published: May 2011

Testicular germ‐cell tumours (TGCT) are the most frequent solid tumour to affect young Caucasian adult males and have increased in incidence over recent decades. In clinical stage I non‐seminomas, (NSGCT) histological vascular invasion (VI) is a prognostic factor for metastatic relapse. Using array comparative genomic hybridization, we have previously shown that the presence of VI is associated with gain of a region at 17q12, containing a cluster of genes encoding inflammatory cytokines. We here confirm this finding using fluorescence in situ hybridization (FISH) demonstrating gain in 12 out of 42 (29%) assessable samples. Interrogation of previously published expression microarray data suggests that of the genes contained within this region, CCL2 [monocyte chemoattractant protein 1 (MCP1)] is frequently overexpressed in TGCT. Immunohistochemistry confirms this finding in a collection of 67 clinical stage I NSGCT, demonstrating an association with the presence of VI (p = 0.049) that was not seen with VEGF‐A, MMP2 or MMP9, although all were frequently expressed. This work gives further insight into the mechanisms involved in invasion in this tumour type, which may ultimately have implications for the management of patients with stage I disease.
Gene expression alterations at baseline and following moderate exercise in patients with Chronic Fatigue Syndrome and Fibromyalgia Syndrome
Authors: Light A. R. , Bateman L. , Jo D. , Hughen R. W. , VanHaitsma T. A. , White A. T. , Light K. C.
Published: May 2011

Abstract.  Light AR, Bateman L, Jo D, Hughen RW, VanHaitsma TA, White AT, Light KC (University of Utah, Salt Lake City, UT, USA). Gene expression alterations at baseline and following moderate exercise in patients with Chronic Fatigue Syndrome and Fibromyalgia Syndrome. J Intern Med 2012; 271: 64–81.

Objectives.  To determine mRNA expression differences in genes involved in signalling and modulating sensory fatigue, and muscle pain in patients with chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FM) at baseline, and following moderate exercise.

Design.  Forty‐eight patients with CFS only, or CFS with comorbid FM, 18 patients with FM that did not meet criteria for CFS, and 49 healthy controls underwent moderate exercise (25 min at 70% maximum age‐predicted heart rate). Visual‐analogue measures of fatigue and pain were taken before, during and after exercise. Blood samples were taken before and 0.5, 8, 24 and 48 h after exercise. Leucocytes were immediately isolated from blood, number coded for blind processing and analyses and flash frozen. Using real‐time, quantitative PCR, the amount of mRNA for 13 genes (relative to control genes) involved in sensory, adrenergic and immune functions was compared between groups at baseline and following exercise. Changes in amounts of mRNA were correlated with behavioural measures and functional clinical assessments.

Results.  No gene expression changes occurred following exercise in controls. In 71% of patients with CFS, moderate exercise increased most sensory and adrenergic receptor’s and one cytokine gene’s transcription for 48 h. These postexercise increases correlated with behavioural measures of fatigue and pain. In contrast, for the other 29% of patients with CFS, adrenergic α‐2A receptor’s transcription was decreased at all time‐points after exercise; other genes were not altered. History of orthostatic intolerance was significantly more common in the α‐2A decrease subgroup. FM‐only patients showed no postexercise alterations in gene expression, but their pre‐exercise baseline mRNA for two sensory ion channels and one cytokine were significantly higher than controls.

Conclusions.  At least two subgroups of patients with CFS can be identified by gene expression changes following exercise. The larger subgroup showed increases in mRNA for sensory and adrenergic receptors and a cytokine. The smaller subgroup contained most of the patients with CFS with orthostatic intolerance, showed no postexercise increases in any gene and was defined by decreases in mRNA for α‐2A. FM‐only patients can be identified by baseline increases in three genes. Postexercise increases for four genes meet published criteria as an objective biomarker for CFS and could be useful in guiding treatment selection for different subgroups.
Determinants of sleep quality in middle‐aged women with fibromyalgia syndrome
Authors: MUNGUÍA‐IZQUIERDO DIEGO , LEGAZ‐ARRESE ALEJANDRO
Published: May 2011

The objectives of this study were: (i) to compare the sleep quality at home of patients with fibromyalgia with that of healthy controls; and (ii) to examine the factors associated with sleep quality in patients with fibromyalgia. In addition to anthropometric measures, 75 women with fibromyalgia and 48 healthy controls completed standardized questionnaires that assessed sleep quality, functional impairment (Fibromyalgia Impact Questionnaire), depression, anxiety and physical activity level. Comparisons between groups, correlation coefficients and a series of hierarchical multiple regressions were performed. The global Pittsburgh Sleep Quality Index scores were worse in patients with fibromyalgia than in the controls. This result was partly explained by the Fibromyalgia Impact Questionnaire score. For the patients with fibromyalgia, the results of the first model that tested the importance of demographic factors were not statistically significant. In the disease‐related model, the duration of symptoms and symptom severity contributed to poor sleep quality. A measurement of physical activity participation and the sum of the skinfold thickness were added to the demographic factors. In the psychological model, the level of anxiety contributed to poor sleep quality. When all variables were entered simultaneously, the level of physical activity, duration of symptoms and symptom severity remained significant determinants of sleep quality. In conclusion, our results showed that the symptoms associated with fibromyalgia contributed to poor overall sleep quality in patients compared with healthy subjects. The findings also suggest that the duration of symptoms, symptom severity and especially a sedentary lifestyle contributed to decreased sleep quality in patients with fibromyalgia.
Interactions among Trypanosoma brucei RAD51 paralogues in DNA repair and antigenic variation
Authors: Dobson Rachel , Stockdale Christopher , Lapsley Craig , Wilkes Jonathan , McCulloch Richard
Published: May 2011

Homologous recombination in Trypanosoma brucei is used for moving variant surface glycoprotein (VSG) genes into expression sites during immune evasion by antigenic variation. A major route for such VSG switching is gene conversion reactions in which RAD51, a universally conserved recombinase, catalyses homology‐directed strand exchange. In any eukaryote, RAD51‐directed strand exchange in vivo is mediated by further factors, including RAD51‐related proteins termed Rad51 paralogues. These appear to be ubiquitously conserved, although their detailed roles in recombination remain unclear. In T. brucei, four putative RAD51 paralogue genes have been identified by sequence homology. Here we show that all four RAD51 paralogues act in DNA repair, recombination and RAD51 subnuclear dynamics, though not equivalently, while mutation of only one RAD51 paralogue gene significantly impedes VSG switching. We also show that the T. brucei RAD51 paralogues interact, and that the complexes they form may explain the distinct phenotypes of the mutants as well as observed expression interdependency. Finally, we document the Rad51 paralogues that are encoded by a wide range of protists, demonstrating that the Rad51 paralogue repertoire in T. brucei is unusually large among microbial eukaryotes and that one member of the protein family corresponds with a key, conserved eukaryotic Rad51 paralogue.
Characterization of a novel variant allele, HLA‐C*07:01:19, identified in a Chinese Han individual
Authors: He L. , Deng Z. , Xu Y. , Wang D.
Published: May 2011

The novel HLA‐C*07:01:19 allele differs from the closest allele C*07:01:01 by a single nucleotide change at coding sequence nucleotide 738 G>A (codon 222 GAG>GAA) in exon 4.