bluuebunny/crossref_metadata_2025 huggingface dataset:
Retention and mobility of the mammalian lamin B receptor in the plant nuclear envelope
Authors: Graumann Katja , Irons Sarah L. , Runions John , Evans David E.
Published: December 2008

Background information. In a previous study, we showed that GFP (green fluorescent protein) fused to the N‐terminal 238 amino acids of the mammalian LBR (lamin B receptor) localized to the NE (nuclear envelope) when expressed in the plant Nicotiana tabacum. The protein was located in the NE during interphase and migrated with nuclear membranes during cell division. Targeting and retention of inner NE proteins requires several mechanisms: signals that direct movement through the nuclear pore complex, presence of a transmembrane domain or domains and retention by interaction with nuclear or nuclear‐membrane constituents.

Results. Binding mutants of LBR—GFP were produced to investigate the mechanisms for the retention of LBR in the NE. FRAP (fluorescence recovery after photobleaching) analysis of mutant and wild‐type constructs was employed to examine the retention of LBR—GFP in the plant NE. wtLBR—GFP (wild‐type LBR—GFP) was shown to have significantly lower mobility in the NE than the lamin‐binding domain deletion mutant, which showed increased mobility in the NE and was also localized to the endoplasmic reticulum and punctate structures in some cells. Modification of the chromatin‐binding domain resulted in the localization of the protein in nuclear inclusions, in which it was immobile.

Conclusions. As expression of truncated LBR—GFP in plant cells results in altered targeting and retention compared with wtLBR—GFP, we conclude that plant cells can recognize the INE (inner NE)‐targeting motif of LBR. The altered mobility of the truncated protein suggests that not only do plant cells recognize this signal, but also have nuclear proteins that interact weakly with LBR.
Cryogenic current-in-plane tunneling apparatus
Authors: Weiss Nicolas , Drechsler Ute , Despont Michel , Parkin Stuart S. P.
Published: December 2008

We have designed and fabricated a cryogenic variable-temperature current-in-plane tunneling apparatus to measure the magnetoresistive properties of unpatterned magnetic tunnel junction wafers as a function of temperature. The wafer is mounted on the cold finger of a liquid helium continuous flow cryostat. The temperature can be continuously varied between 7 and 330K. We describe the design and fabrication of the micromachined silicon probe head that comprises a comb of 20 measuring and 4 leveling probes. The measuring probes are typically 0.7μm wide and 1.2μm thick, with lengths of 10, 7, and 4μm, and a pitch that varies from 1.5to30μm. The leveling probes are used in conjunction with a tilt stage to adjust the parallelism between the comb and the sample wafer during the approach of the probe head. The probe head is mounted on a nonmagnetic x-y stage, which can access a 22×22mm2 area with a repeatability of ∼1μm. The first measurements taken at room and cryogenic temperatures are shown.
Thermodynamics of droplet formation around a soluble condensation nucleus in the atmosphere of a solvent vapor
Authors: Shchekin A. K. , Shabaev I. V. , Rusanov A. I.
Published: December 2008

An expression for the work of formation of a spherical droplet condensing on a soluble condensation nucleus out of a solvent vapor is derived. The dependence of the formation work on the solvent vapor chemical potential and the droplet and the nucleus residue sizes is analyzed. The balance of the solute matter between the liquid film and the nucleus residue and the effect of overlapping the surface layers of the thin film have been taken into account. It is shown that the equations of the chemical equilibrium of a solute and a solvent in the droplet, resulting from the generating properties of the formation work, coincide with the generalized Gibbs–Kelvin–Köhler and Ostwald–Freundlich equations. The numerical solution of these equations at a fixed number of molecules of the nucleus matter (at an initial size of the nucleus specified) has been performed in the case of the solvent vapor undersaturated over the bulk liquid solvent phase. The solution links the equilibrium sizes of the droplet and the soluble nucleus residue with the chemical potential or the pressure of the solvent vapor saturated over the droplet. It also determines the limiting sizes of the droplet with small nucleus residue above which the chemical equilibrium of the residue surface and the solution film does not exist. The existence of the limiting sizes is responsible for the specific behavior of the droplet thermodynamic characteristics and the work of droplet formation at deliquescence transition from the droplet state with a partly dissolved nucleus to the state of complete dissolution of the nucleus.
Theoretical investigation of the fundamental mode frequency of the magnetically insulated transmission line oscillator
Authors: Fan Yu-Wei , Zhong Hui-Huang , Shu Ting , Li Zhi-Qiang
Published: December 2008

The fundamental mode frequency of a magnetically insulated transmission line oscillator is investigated theoretically by the equivalent circuit method, and an exact theoretical formula about the fundamental mode frequency is given. The theoretical results are compared with the simulation and experimental results, which shows that the relative error, which is calculated according to the theoretical and simulation frequencies, is less than 3%, so the validity of the theoretical formula is verified.
Time-resolved photoluminescence properties of AlGaN/AlN/GaN high electron mobility transistor structures grown on 4H-SiC substrate
Authors: Pozina G. , Hemmingsson C. , Forsberg U. , Lundskog A. , Kakanakova-Georgieva A. , Monemar B. , Hultman L. , Janzén E.
Published: December 2008

AlGaN/AlN/GaN high electron mobility transistor heterostructures grown by metal-organic chemical vapor deposition have been studied by temperature dependent time-resolved photoluminescence. The AlGaN-related emission is found to be sensitive to the excitation power and to the built-in internal electric field. In addition, this emission shows a shift to higher energy with the reduction in the excitation density, which is rather unusual. Using a self-consistent calculation of the band potential profile, we suggest a recombination mechanism for the AlGaN-related emission involving electrons confined in the triangular AlGaN quantum well and holes weakly localized due to potential fluctuations.
The effects of the microstructure of ZnO films on the electrical performance of their thin film transistors
Authors: Hwang Byung-Il , Park Kyung , Chun Ha-Suk , An Chee-Hong , Kim Hyoungsub , Lee Hoo-Jeong
Published: December 2008

This study examined a fundamental aspect of ZnO-based thin film transistors (TFTs): the connection between the deposition conditions and the microstructure of ZnO films, and the electrical performance of the TFTs. We characterized the microstructure of ZnO films deposited under various rf powers by using high resolution transmission electron microscopy and x-ray diffraction. In further investigating the effects of the microstructure on the device performance, we experimentally demonstrated that the electrical mobility of the devices was coupled to the grain size of the ZnO films in an exponential function.
A sensitive and high dynamic range cw laser power meter
Authors: Krishnan S. , Bindra K. S. , Oak S. M.
Published: December 2008

We report the design of a cost effective, highly sensitive cw laser power meter with a large dynamic range based on a photodiode. The power meter consists of a photodiode, a current to voltage converter circuit, an offset balancing circuit, a microcontroller, an analog to digital converter, reed relays, and an alphanumeric liquid crystal display. The power meter can record absolute laser power levels as low as 1 pW. The dynamic range measured with a cw laser at a wavelength of 532 nm is 8×1010. The high sensitivity and large dynamic range are achieved by the implementation of an analog background balancing circuit and autoranging.
Experimental investigation of standing wave interactions with a magnetized plasma in a minimum-B field
Authors: Dey Indranuj , Bhattacharjee Sudeep
Published: December 2008

Standing waves in the microwave regime are generated by a superposition of forward and backward moving waves induced by reflections from geometrical transitions in the plasma vacuum boundary. The waves are preferentially damped in the weakly collisional (νen∕ω≅10−4) plasma near the launch region (∼3−15cm), where the electron temperature has a higher than average value (Te>Teavg∼12eV). Typical e-folding damping lengths are of the order of 10cm, and depend upon the wave power and plasma collisionality. Fourier spectrum of the standing waves indicates about 23% downshift in the vacuum wave-number due to plasma dispersion. Electron trapping is observed in the potential troughs of the waves.
Excitation and trapping of lower hybrid waves in striations
Authors: Borisov N. , Honary F.
Published: December 2008

The theory of lower hybrid (LH) waves trapped in striations in warm ionospheric plasma in the three-dimensional case is presented. A specific mechanism of trapping associated with the linear transformation of waves is discussed. It is shown analytically that such trapping can take place in elongated plasma depletions with the frequencies below and above the lower hybrid resonance frequency of the ambient plasma. The theory is applied mainly to striations generated artificially in ionospheric modification experiments and partly to natural plasma depletions in the auroral upper ionosphere. Typical amplitudes and transverse scales of the trapped LH waves excited in ionospheric modification experiments are estimated. It is shown that such waves possibly can be detected by backscattering at oblique sounding in very high frequency (VHF) and ultra high frequency (UHF) ranges.
Suppression of photorefractive damage with aid of steady-state temperature gradient in nominally pure LiNbO3 crystals
Authors: Kostritskii S. M. , Sevostyanov O. G. , Aillerie M. , Bourson P.
Published: December 2008

Photorefractive damage (PRD) in as-grown, oxidized, and slightly reduced nominally pure LiNbO3, and iron-doped crystals with different compositions has been studied with the closed-aperture Z-scan and pseudo-Z-scan techniques at uniform temperature distribution, as well as at a steady-state temperature gradient ∇T, created by two external thermoelectric elements in the transverse direction to the light beam trajectory. The most important experimental finding consists of the demonstration of the possibility of a full PRD suppression in nominally pure crystals with the aid of a relatively small temperature gradient (12.5–84 K/cm), if ∇T is above a threshold value specific for each crystal studied. The threshold ∇Tth decreases significantly with the increase in the so-called bipolaron absorption band (center at 470–500 nm) in the optical spectra, and it is not correlated with the composition of the crystals within the studied range of compositions ([Li]/[Nb]=0.946–0.983). No any partial suppression of PRD was observed in iron-doped ([Fe]≥0.01 wt %) lithium niobate crystals, even at the largest temperature gradient (85 K/cm) used in our study. To explain these experimental results, we use theoretical model taking into account local changes of spontaneous polarization (i.e., polarization charge field) at photoionization of intrinsic defects (polarons, bipolarons, and hole polarons). It has been shown that a steady-state temperature gradient may induce a local thermoelectric current of light-induced charge carriers and their instant recombination, resulting in a decrease in the polarization space-charge field and hence, a light-induced refractive index change. The latter mechanism may induce the full PRD suppression, if macroscopic charge separation (space-charge field effect) gives insignificant contribution to the total light-induced electric field, as in as-grown and reduced nominally pure LiNbO3 crystals.
Gyrokinetic-water-bag modeling of low-frequency instabilities in a laboratory magnetized plasma column
Authors: Gravier E. , Klein R. , Morel P. , Besse N. , Bertrand P.
Published: December 2008

A new model is presented, named collisional-gyro-water-bag (CGWB), which describes the collisional drift waves and ion-temperature-gradient (ITG) instabilities in a plasma column. This model is based on the kinetic gyro-water-bag approach recently developed [P. Morel et al., Phys. Plasmas 14, 112109 (2007)] to investigate ion-temperature-gradient modes. In CGWB electron-neutral collisions have been introduced and are now taken into account. The model has been validated by comparing CGWB linear analysis with other models previously proposed and experimental results as well. Kinetic effects on collisional drift waves are investigated, resulting in a less effective growth rate, and the transition from collisional drift waves to ITG instability depending on the ion temperature gradient is studied.
Controllable light transmission through cascaded metal films perforated with periodic hole arrays
Authors: He Meng-Dong , Wang Ling-Ling , Liu Jian-Qiang , Zhai Xiang , Wan Qing , Chen Xiaoshuang , Zou B. S.
Published: December 2008

The transmission of linearly polarized plane wave through cascaded metal films perforated with periodic hole arrays is investigated by using the three-dimensional finite-difference time-domain method. The results show that the transmission spectra can be controlled by changing the longitudinal interval G and/or the lateral displacements Lx and Ly, which are parallel and perpendicular to the polarization direction of the incident light, respectively. The variation in longitudinal interval G results in a redshift or blueshift of the transmission peak due to the coupling of the localized surface plasmon (LSP) modes on two metal layers. The lateral displacement Lx leads to the splitting of the transmission peak, originating from the variation in the coupling manner of LSP modes, while the lateral displacement Ly suppresses the transmission peak.
Field-effect transistor fabricated with nickel(II) etioporphyrin-I micrometer-sized crystals
Authors: Xu Zong-Xiang , Xiang Hai-Feng , Roy V. A. L. , Chui Stephen Sin-Yin , Che Chi-Ming , Lai P. T.
Published: December 2008

We fabricated a field-effect transistor using micrometer-sized crystals (10–40 μm) of nickel(II) etioporphyrin-I NiOX as active material. Microwires and micrometer-sized crystals of NiOX were obtained by heating NiOX thin film under high vacuum. Through this method, traps due to solvent molecules could be avoided. The transistor fabricated with these micrometer-sized crystals has a hole mobility of 0.15±0.03 cm2 V−1 s−1, which is two orders of magnitude higher than that obtained with the thin film structure (1.1×10−3 cm2 V−1 s−1).
Channel length dependence of hot-carrier-induced degradation in n-type drain extended metal-oxide-semiconductor transistors
Authors: Chen Jone F. , Chen Shiang-Yu , Wu Kuo-Ming , Liu C. M.
Published: December 2008

Channel length (Lch) dependence of hot-carrier-induced degradation in n-type drain extended metal-oxide-semiconductor (DEMOS) transistors stressed under high drain voltage and high gate voltage is investigated. On-resistance degradation is reduced in longer Lch device, however, threshold voltage shift (ΔVT) is greater. Charge pumping data reveal that electron trapping in gate oxide above channel region is responsible for ΔVT. Simulation results show that longer Lch device exhibits enhanced vertical electric field (Ey), i.e., enhanced hot-electron injection, in channel region due to the alleviation of Kirk effect. Results presented in this letter reveal that enhanced ΔVT driven by enhanced channel Ey may become a serious reliability concern in DEMOS transistors with longer Lch.
Microstructural and optical analysis of superresolution phenomena due to Ge2Sb2Te5 thin films at blue light regime
Authors: Lee Hyun Seok , Lee Taek Sung , Lee Yongwoon , Kim Jooho , Lee Suyoun , Huh Joo-Youl , Kim Donghwan , Cheong Byung-ki
Published: December 2008

Superresolution (SR) phenomena due to Ge2Sb2Te5 films were examined by combined analysis of the transmission electron microscopy (TEM) microstructures of the laser-irradiated films and the results from dynamic and static tests using blue lasers. A new finding was made that comprises a complementary case of the classical SR readout by Ge2Sb2Te5 film; an amorphous band instead of a closed aperture of melt in the crystalline background forms behind a moving laser but still produces a high SR signal. A complete carrier-to-noise-ratio curve of a SR-read-only memory employing Ge2Sb2Te5 may be derived from a nonlinear optical effect, specifically thermally assisted saturable absorption.
Left-right asymmetry of the hippocampal synapses with differential subunit allocation of glutamate receptors
Authors: Shinohara Yoshiaki , Hirase Hajime , Watanabe Masahiko , Itakura Makoto , Takahashi Masami , Shigemoto Ryuichi
Published: December 2008

Left-right asymmetry of the brain has been studied mostly through psychological examination and functional imaging in primates, leaving its molecular and synaptic aspects largely unaddressed. Here, we show that hippocampal CA1 pyramidal cell synapses differ in size, shape, and glutamate receptor expression depending on the laterality of presynaptic origin. CA1 synapses receiving neuronal input from the right CA3 pyramidal cells are larger and have more perforated PSD and a GluR1 expression level twice as high as those receiving input from the left CA3. The synaptic density of GluR1 increases as the size of a synapse increases, whereas that of NR2B decreases because of the relatively constant NR2B expression in CA1 regardless of synapse size. Densities of other major glutamate receptor subunits show no correlation with synapse size, thus resulting in higher net expression in synapses having right input. Our study demonstrates universal left-right asymmetry of hippocampal synapses with a fundamental relationship between synaptic area and the expression of glutamate receptor subunits.
Enhancing nuclear receptor-induced transcription requires nuclear motor and LSD1-dependent gene networking in interchromatin granules
Authors: Hu Qidong , Kwon Young-Soo , Nunez Esperanza , Cardamone Maria Dafne , Hutt Kasey R. , Ohgi Kenneth A. , Garcia-Bassets Ivan , Rose David W. , Glass Christopher K. , Rosenfeld Michael G. , Fu Xiang-Dong
Published: December 2008

Although the role of liganded nuclear receptors in mediating coactivator/corepressor exchange is well-established, little is known about the potential regulation of chromosomal organization in the 3-dimensional space of the nucleus in achieving integrated transcriptional responses to diverse signaling events. Here, we report that ligand induces rapid interchromosomal interactions among specific subsets of estrogen receptor α-bound transcription units, with a dramatic reorganization of nuclear territories, which depends on the actions of nuclear actin/myosin-I machinery and dynein light chain 1. The histone lysine demethylase, LSD1, is required for these ligand-induced interactive loci to associate with distinct interchromatin granules, long thought to serve as “storage” sites for the splicing machinery, some critical transcription elongation factors, and various chromatin remodeling complexes. We demonstrate that this 2-step nuclear rearrangement is essential for achieving enhanced, coordinated transcription of nuclear receptor target genes.
Effect of barium sulfate contrast medium on rheology and sensory texture attributes in a model food
Authors: Ekberg O. , Bülow M. , Ekman S. , Hall G. , Stading M. , Wendin K.
Published: December 2008

Background: The swallowing process can be visualized using videoradiography, by mixing food with contrast medium, e.g., barium sulfate (BaSO4), making it radiopaque. The sensory properties of foods may be affected by adding this medium.

Purpose: To evaluate if and to what extent sensory and rheological characteristics of mango purée were altered by adding barium sulfate to the food.

Material and Methods: This study evaluated four food samples based on mango purée, with no or added barium sulfate contrast medium (0%, 12.5%, 25.0%, and 37.5%), by a radiographic method, and measured sensory texture properties and rheological characteristics. The sensory evaluation was performed by an external trained panel using quantitative descriptive analysis. The ease of swallowing the foods was also evaluated.

Results: The sensory texture properties of mango purée were significantly affected by the added barium in all evaluated attributes, as was the perception of particles. Moreover, ease of swallowing was significantly higher in the sample without added contrast medium. All samples decreased in extensional viscosity with increasing extension rate, i.e., all samples were tension thinning. Shear viscosity was not as dependent on the concentration of BaSO4 as extensional viscosity.

Conclusion: Addition of barium sulfate to a model food of mango purée has a major impact on perceived sensory texture attributes as well as on rheological parameters.
Venous saturation slab causes overestimation of stenosis length in two-dimensional time-of-flight magnetic resonance angiography
Authors: Wikström J. , Bjornerud A. , McGill S. , Johansson L.
Published: December 2008

Background: The use of downstream saturation slabs in two-dimensional time-of-flight magnetic resonance angiography (2D TOF MRA) of the arterial system eliminates signal from regions with countercurrent flow, as seen in veins, but possibly also beyond arterial stenoses because of flow turbulence.

Purpose: To investigate the contribution of a downstream saturation slab to signal intensity (SI) loss beyond stenoses at 2D TOF MRA.

Material and Methods: 2D TOF MRA was performed on a bifurcation phantom with a tight stenosis at 1.5T during pulsatile flow. Qualitative and quantitative evaluations of stenosis delineation were performed with different echo times (TE) (3.7 or 7.0 ms), spatial resolution (1x1x1 or 1x1x5 mm3), and with or without a downstream saturation slab. For reference, a high-resolution contrast-enhanced sequence without flow was obtained.

Results: The downstream saturation slab caused severe signal loss immediately distal to the stenosis, causing overestimation of stenosis length. This region corresponded with a region of poststenotic flow jet, where turbulence is expected. With increase in TE, there was some increased SI loss at the level of maximum stenosis. A lower spatial resolution resulted in overall poorer delineation of the stenosis.

Conclusion: Using clinically relevant sequence parameters, the use of a downstream saturation slab at 2D TOF MRA was found to be a major contributor to signal loss in stenotic regions, which can result in an overestimation of stenosis length.
Interaction of Brassicaceous Seed Meal and Apple Rootstock on Recovery of Pythium spp. and Pratylenchus penetrans from Roots Grown in Replant Soils
Authors: Mazzola Mark , Brown Jack , Zhao Xiaowen , Izzo Antonio D. , Fazio Gennaro
Published: December 2008

Pythium spp. and Pratylenchus penetrans are significant components of the diverse pathogen complex that incites apple replant disease in Washington State. The structure of the Pythium population differs among orchard soils but is composed of multiple pathogenic species. Studies were conducted to determine the effect of brassicaceous seed meals and apple rootstock on the activity and composition of these pathogen populations. Brassicaceous seed meals differed in capacity to suppress Pythium numbers and apple root infection, as well as differentially transformed composition of the population recovered from apple roots. Brassica juncea seed meal (SM) was the sole seed meal examined to suppress Pythium numbers and root infection; however, a persisting population was always detected in which Pythium irregulare existed as the dominant or co-dominant species. In general, the Geneva series rootstocks were less susceptible to root infection by native populations of Pythium, whereas M26, MM106, and MM111 were highly susceptible. Apple rootstocks from the Geneva series consistently supported lower populations of P. penetrans than did Malling or Malling-Merton rootstocks. B. juncea SM was superior to Brassica napus SM or Sinapis alba SM in suppressing lesion nematode populations. Significant rootstock × seed meal interaction was detected, and nematode suppression in response to B. napus or S. alba SM was only observed when used in concert with a tolerant rootstock, while B. juncea SM suppressed lesion nematode root populations irrespective of rootstock. These findings demonstrate that utilization of brassicaceous seed meal amendments for replant disease suppression must employ an appropriate rootstock in order to achieve optimal disease control.
Effects of Aphanomyces Root Rot on Carbohydrate Impurities and Sucrose Extractability in Postharvest Sugar Beet
Authors: Klotz Karen L. , Campbell Larry G.
Published: December 2008

Sugar beet (Beta vulgaris) roots with rot caused by Aphanomyces cochlioides often are incorporated into storage piles even though effects of disease on processing properties are unknown. Roots with Aphanomyces root rot were harvested from six fields over 2 years. For each field, roots with similar disease symptoms were combined and assigned a root rot index (RRI) value (0 to 100; 0, no rot symptoms; 100, all roots severely rotted). After 20 or 120 days storage at 4°C and 95% relative humidity, concentrations of the major carbohydrate impurities that accumulate during storage and sucrose extractability were determined. Root rot affected carbohydrate impurity concentrations and sucrose extractability in direct relation to disease severity symptoms. Generally, roots with active and severe infection (RRI ≥ 85) exhibited elevated glucose and fructose concentrations 20 and 120 days after harvest (DAH), elevated raffinose concentration 120 DAH, and reduced sucrose extractability 20 and 120 DAH. Roots with minor or moderate disease symptoms (RRI 20 to 69), or damaged roots with no signs of active infection, had similar carbohydrate impurity concentrations and sucrose extractability after 20 and 120 days storage. Processing properties declined when RRIs exceeded 43, as determined by regression analysis, or when storage duration increased from 20 to 120 days. Results indicate that both disease severity and anticipated duration of storage be considered before Aphanomyces-infected roots are incorporated into storage piles.
First Report of Botrytis Blight Caused by Botrytis cinerea on Gaura lindheimeri in Italy
Authors: Garibaldi A. , Bertetti D. , Pensa P. , Gullino M. L.
Published: December 2008

Gaura lindheimeri (wand flower) is a perennial plant belonging to the Onagraceae family that is used for perennial borders in xeric and mesic landscapes. It produces flowers floating above the plant like small, dancing butterflies. This plant is becoming popular in the Albenga Region (northern Italy) where white and rose varieties are grown as potted plants. In January of 2008, 5-month-old ‘Whirling Butterflies’ plants grown in plastic pots (14 cm in diameter) in the open field started showing symptoms of a previously unknown blight. When the disease developed, temperatures ranged between 3 and 17°C (average 9°C) and average relative humidity was 64%. Small, brown spots appeared on the basal portion of leaves first, eventually spreading to cover entire leaves. Subsequently, the pathogen developed abundant, soft gray mycelium on affected leaf tissue. Severely infected leaves eventually became completely rotten and desiccated. Sixty percent of plants were affected by the disease. Tissues were excised from diseased leaves, immersed in a solution containing 1% sodium hypochlorite for 10 s, and then cultured on potato dextrose agar (PDA) medium. The fungus produced abundant mycelium on PDA medium when incubated under constant fluorescent light at 22 ± 1°C. The conidia were smooth, hyaline, globoid, measuring 11.8 to 9.4 × 8.3 to 6.6 (average 10.7 × 7.4) μm, and are similar to those described for Botrytis cinerea. The identity of the pathogen was also confirmed by the production of numerous sclerotia on PDA plates incubated for 20 days at 8 ± 1°C. Sclerotia were dark, irregular, and measured 3 to 4 × 2 to 3 mm. The fungus was identified as B. cinerea on the basis of these characters (1). Pathogenicity tests were performed by spraying leaves of healthy, potted 8-month-old G. lindheimeri ‘Whirling Butterflies’ plants with a 105 conidia/ml suspension. Plants sprayed with water only served as controls. Five plants per treatment were used. Plants were covered with plastic bags for 6 days after inoculation and maintained in a growth chamber at 20 ± 1°C. The first foliar lesions developed on leaves 5 days after inoculation, whereas control plants remained healthy. B. cinerea was consistently reisolated from these lesions. The pathogenicity test was completed twice. To our knowledge, this is the first report of the presence of B. cinerea on G. lindheimeri in Italy. The economic importance of this disease will increase with the increased cultivation of this species.

Reference: (1) H. L. Barnett and B. B. Hunter. Illustrated Genera of Imperfect Fungi. Burgess Publishing Company, Minneapolis, MN, 1972.
Release of yeast telomeres from the nuclear periphery is triggered by replication and maintained by suppression of Ku-mediated anchoring
Authors: Ebrahimi Hani , Donaldson Anne D.
Published: December 2008

The perinuclear localization of Saccharomyces cerevisiae telomeres provides a useful model for studying mechanisms that control chromosome positioning. Telomeres tend to be localized at the nuclear periphery during early interphase, but following S phase they delocalize and remain randomly positioned within the nucleus. We investigated whether DNA replication causes telomere delocalization from the nuclear periphery. Using live-cell fluorescence microscopy, we show that delaying DNA replication causes a corresponding delay in the dislodgment of telomeres from the nuclear envelope, demonstrating that replication of individual telomeres causes their delocalization. Telomere delocalization is not simply the result of recruitment to a replication factory in the nuclear interior, since we found that telomeric DNA replication can occur either at the nuclear periphery or in the nuclear interior. The telomere-binding complex Ku is one of the factors that localizes telomeres to the nuclear envelope. Using a gene locus tethering assay, we show that Ku-mediated peripheral positioning is switched off after DNA replication. Based on these findings, we propose that DNA replication causes telomere delocalization by triggering stable repression of the Ku-mediated anchoring pathway. In addition to maintaining genetic information, DNA replication may therefore regulate subnuclear organization of chromatin.
Compartmentalization regulates the interaction between the platelet integrin αIIbβ3 and ICln
Authors: Larkin Deirdre , Treumann Achim , Murphy Derek , DeChaumont Ciaran , Kiernan Aoife , Moran Niamh
Published: December 2008

The volume‐regulating protein, ICln, interacts with the conserved KxGFFKR α‐integrin signature motif. ICln is an abundant protein (4455 ± 650 molecules/platelet) found exclusively in the soluble cytosolic fraction of unactivated platelets. In contrast, its binding partner, the platelet integrin αIIbβ3, is present in detergent‐insoluble fractions associated with membrane and cytoskeleton subcellular localizations. This study investigated factors that regulate the interaction of ICln with αIIbβ3 during platelet activation. His‐tagged recombinant ICln bound equally to purified αIIbβ3 and to integrin from resting or activated platelets. Binding was not affected by direct integrin activation with Mn++ or by inhibitors of integrin occupancy (abciximab, RGD). However, the capacity for interaction between integrin and recombinant ICln was slowly downregulated following prolonged platelet activation for >300 s. In parallel, ICln redistributed to membrane and cytoskeletal platelet subcellular fractions. The time‐course of this redistribution preceded the downregulation of integrin binding capacity and suggests that only a short window of opportunity exists for ICln interaction with αIIbβ3 to occur. Thus, although ICln has the inherent capacity to bind to αIIbβ3 regardless of its activation state, it can only do so following platelet activation. Activation‐dependent subcellular redistribution of ICln represents a novel, temporally‐regulated mechanism for control of integrin function in platelets.
The Restoration of Phytophagous Beetles in Species‐Rich Chalk Grasslands
Authors: Woodcock Ben A. , Edwards Andrew R. , Lawson Clare S. , Westbury Duncan B. , Brook Alex J. , Harris Stephanie J. , Masters Greg , Booth Roger , Brown Valerie K. , Mortimer Simon R.
Published: December 2008

This study focuses on the restoration of chalk grasslands over a 6‐year period and tests the efficacy of two management practices, hay spreading and soil disturbance, in promoting this process for phytophagous beetles. Restoration success for the beetles, measured as similarity to target species–rich chalk grassland, was not found to be influenced by either management practice. In contrast, restoration success for the plants did increase in response to hay spreading management. Although the presence of suitable host plants was considered to dictate the earliest point at which phytophagous beetles could successfully colonized, few beetle species colonized as soon as their host plants became established. Morphological characteristics and feeding habits of 27 phytophagous beetle species were therefore tested to identify factors that limited their colonization and persistence. The lag time between host plant establishment and colonization was greatest for flightless beetles. Beetles with foliage‐feeding larvae both colonized at slower rates than seed‐, stem‐, or root‐feeding species and persisted within the swards for shorter periods. Although the use of hay spreading may benefit plant communities during chalk grassland restoration, it did not directly benefit phytophagous beetles. Without techniques for overcoming colonization limitation for invertebrate taxa, short‐term success of restoration may be limited to the plants only.
Complex time‐dependent alterations in the brain expression of different drug efflux transporter genes after status epilepticus
Authors: Kuteykin‐Teplyakov Konstantin , Brandt Claudia , Hoffmann Katrin , Löscher Wolfgang
Published: December 2008

Purpose:  Frequent epileptic seizures or prolonged seizure activity (status epilepticus, SE) is known to increase the brain expression of drug efflux transporter genes and proteins, such as P‐glycoprotein (Pgp) and members of the multidrug resistance protein (MRP) family, which might reduce brain levels of antiepileptic drugs and, therefore, be involved in drug resistance. However, the time course of alterations in Pgp or MRPs after seizures or SE is only incompletely known.

Methods:  This prompted us to study the time course of alterations in the expression of different efflux transporter genes (Mdr1a, Mdr1b, MRP1, MRP2, MRP5) at various times after a pilocarpine‐induced SE in limbic brain regions, using quantitative real‐time polymerase chain reaction (RT‐PCR) (qPCR).

Results:  Unexpectedly, between 6 and 24 h after onset of SE, genes encoding Pgp (Mdr1a, Mdr1b), Mrp1, and Mrp5 were downregulated in hippocampus, amygdala, or piriform cortex. This initial decrease in expression was followed by normalization and then increased expression, which became maximal 2 days after SE. One explanation for the initial decrease in transporter expression could be SE‐induced acute inflammatory processes, because proinflammatory cytokines are known to suppress the expression of Pgp and other efflux transporters. To directly address this possibility, we quantified the hippocampal mRNA expression of interleukin‐1β, interleukin‐6, and tumor necrosis factor‐α, showing a marked SE‐induced increase in these cytokines, which paralleled the decreased expression of efflux transporters.

Discussion:  Taken together, these findings indicate that alterations in expression of drug efflux transporters after prolonged seizure activity are more complex than previously thought.
Predator–prey coupling: interaction between mink Mustela vison and muskrat Ondatra zibethicus across Canada
Authors: Holmengen Nina , Lehre Seip Knut , Boyce Mark , Stenseth Nils Chr.
Published: December 2008

In this paper we explore variation in the predator‐prey interaction between mink Mustela vison and muskrat Ondatra zibethicus across Canada based on 25 years of mink (predator) and muskrat (prey) data from the Hudson's Bay Company. We show that predator–prey interactions have stronger signatures in the west of Canada than in the east. In particular, we show that the observed phase plot trajectories of mink and muskrat rotate significantly clock‐wise, consistent with predator–prey theory. We also investigate four phases of the mink muskrat interaction sequence (predator crash phase, prey recovery phase, etc.) and show that they are all consistent with a strong coupling in the west, whereas the presence of generalist predators and alternative preys can explain deviations from this pattern in the east.
Mary and the Vocation of Philosophers
Authors: Allen Prudence
Published: December 2008

Pope John Paul II, in Fides et ratio#108, states that there is a deep harmony between the vocation of true philosophy and the Blessed Virgin Mary. This intriguing claim, so different from the usual link of Mary with faith, is developed in this article. Drawing analogical implications from selected events in Mary's life, two questions will be asked: How do philosophers “philosophize in Mary?;” and how could this way of philosophizing help us today to renew the vocation to be a philosopher? The following authors are considered: Thomas Aquinas, Edith Stein, Jacques and Raïssa Maritain, Bernard Lonergan, Josef Ratzinger, Mary Daly, Robert Sokolowski, Norris Clarke, Søren Kierkegaard, Karol Wojtyla, John Paul Sartre, Simone de Beauvoir, Judy Chicago, and John Henry Newman.
Neo‐Pragmatist (Practice‐Based) Theories of Meaning
Authors: Loeffler Ronald
Published: December 2008

In recent years, several systematic theories of linguistic meaning have been offered that give pride of place to linguistic practice, or the process of linguistic communication. Often these theories are referred to as neo‐pragmatist or new pragmatist; I call them ‘practice‐based’. According to practice‐based theories of meaning, the process of linguistic communication is somehow constitutive of, or otherwise essential for the existence of, propositional linguistic meaning. Moreover, these theories disavow, or downplay, the semantic importance of inflationary notions of representation. I introduce the basic ideas and motives behind some practice‐based theories of meaning, and offer some reasons why an eliminativist, non‐quietist, epistemic practice‐based approach to meaning that 1) disavows any explanatory role for the linguistic community as such, 2) prioritizes sentence meaning over word meaning, and 3) may, in the end, be naturalistic, should be favored over its practice‐based competitors.
Back to Basics in Bioethics: Reconciling Patient Autonomy with Physician Responsibility
Authors: Da Rocha Antonio Casado
Published: December 2008

Although bioethics is a lively and expanding interdisciplinary field, there is not enough research about the patient‐doctor relationship, a central issue in philosophy of medicine. This article surveys the state of the field, paying attention to recent work by Alfred Tauber, and supplementing it with insights from Hans Jonas's philosophy of technology in order to propose a principle of responsible autonomy for health care. Based on a comparative look across different sub‐fields in bioethics, the resulting model claims that physician responsibility is essential to professional integrity, providing an alternative to other active trends emphasizing patient autonomy, such as Robert Veatch's contractual model.
Oral Health of Young Children in Mississippi Delta Child Care Centers: A Second Look at Early Childhood Caries Risk Assessment
Authors: Southward Linda H. , Robertson Angela , Edelstein Burton L. , Hanna Heather , Wells‐Parker Elisabeth , Baggett Dorris H. , Eklund Neva P. , Crall James J. , Silberman Stephen L. , Parrish David R.
Published: December 2008

Objectives: To identify the predictors of early childhood caries and urgent dental treatment need among primarily African‐American children in child care centers in the Delta region of Mississippi. The purpose of this study was to replicate predictors of caries and urgent dental treatment needs that were identified in an earlier study conducted in Delta child care centers and to assess additional caries risk factors not collected in the original study.

Methods: Children in 19 child care centers were examined by the dentists, and the parents provided data on oral health practices, oral health history, and on children's oral health‐related quality of life (QOL). The dentists also assessed visible plaque and tested levels of mutans streptococci. Predictors of caries and treatment need among children 24 to 71 months of age were examined using logistic regression.

Results: Two parent predictors of caries identified in the earlier study (parent flossing and soft/sugary drink consumption) were not predictive in the current study. Parent history of abscess continued to predict their child's urgent need for treatment. Young children's level of salivary mutans streptococci, maxillary incisor visible plaque, and parents' reports of child oral health‐related QOL measures predicted the presence of both caries and urgent treatment need. Some expected predictors, such as frequency of child's toothbrushing, were not predictive of caries.

Conclusions: Parental abscess and parent's report of the child's oral health‐related QOL are risk indicators for poor oral health outcomes that could be used by nondental personnel to identify young children in need of early preventive intervention and dental referral.
Health Literacy in an Adult Dental Research Population: A Pilot Study
Authors: Jackson Richard D. , Eckert George J.
Published: December 2008

Objective: The purpose of this investigation was to gather data concerning the level of health literacy in adults who frequently volunteer for our clinical research programs. Methods: A convenience sample of 99 adults was recruited from our database of subjects taking part in an ongoing series of investigations. Health literacy was measured using the Short Test of Functional Health Literacy in Adults (S‐TOFHLA). Additional demographic and socioeconomic data were collected by means of a questionnaire. Results: The results indicated that 13 percent of the cohort of subjects scored in the “inadequate” or “marginal” categories as described by the criteria of the S‐TOFHLA. Inadequate or marginal health literacy was associated with race, gender, and age. Unfortunately, the sample size was too small to determine the interaction of these variables. Conclusions: Dental faculty conducting clinical research investigations should be cognizant of the fact that a portion of adults, especially older adults, may have difficulty reading written instructions, informational letters of consent, prescriptions, and other documents. Researchers should make every effort to ensure that information provided in text form is provided in a manner that is easily understandable to the reader. Technical terminology and jargon should be avoided or if used, it should be explained in plain, simple language. If a potential subject is having difficulty, the investigator is obligated to take the additional time to educate the potential subject using alternative methods.
Contracting for information under imperfect commitment
Authors: Krishna Vijay , Morgan John
Published: December 2008

We study optimal contracting under imperfect commitment in a model with an uninformed principal and an informed agent. The principal can commit to pay the agent for his advice but retains decision‐making authority. Under an optimal contract, the principal should (i) never induce the agent to fully reveal what he knows—even though this is feasible—and (ii) never pay the agent for imprecise information. We compare optimal contracts under imperfect commitment to those under full commitment as well as to delegation schemes. We find that gains from contracting are greatest when the divergence in the preferences of the principal and the agent is moderate.
The Tribological Study of Novel Benzotriazolyl-Containing Anticorrosive Polysulfides in Rapeseed Oil
Authors: Li Jing , Wu Hua , Ren Tianhui
Published: December 2008

Two novel benzotriazolyl-containing polysulfides were synthesized as a part of the efforts of molecular design. The tribological properties of the synthetic products as additives in rapeseed oil were evaluated using a four-ball machine and compared with that of diiso-butylpolysulfides (DIBPS). The copper corrosion-inhibiting performance and thermal stabilities of the additives were explored as well. The results showed that the synthetic heterocyclic polysulfides had better corrosion-inhibiting properties and thermal stability than the DIBPS. Moreover, the heterocyclic polysulfide additives can improve extreme pressure properties of rapeseed oil as well as antiwear and friction-reducing abilities. However, compared with DIBPS, the heterocyclic polysulfide additives showed a little weaker performance. Tribofilms were investigated by means of scanning electron microscopy and X-ray photoelectron spectroscopy. Surface analysis indicated that the benzotriazolyl-containing polysulfides experienced tribochemical reactions with the rubbing steel surface to generate FeS and FeS2, which together with the chemically absorbed organic N-containing species formed a surface protective film and hence significantly reduce wear of the steel-steel frictional pair. The titled synthetic compounds could be used as promising environmentally friendly multifunctional lubricating additives.
Noise power properties of a cone‐beam CT system for breast cancer detection
Authors: Yang Kai , Kwan Alexander L. C. , Huang Shih‐Ying , Packard Nathan J. , Boone John M.
Published: December 2008

The noise power properties of a cone‐beam computed tomography (CT) system dedicated for breast cancer detection were investigated. Uniform polyethylene cylinders of various diameters were scanned under different system acquisition conditions. Noise power spectra were calculated from difference data generated by subtraction between two identical scans. Multidimensional noise power spectra (NPS) were used as the metric to evaluate the noise properties of the breast CT (bCT) under different system acquisition and reconstruction conditions. A comprehensive investigation of the noise properties was performed in regard to system acquisition parameters including kVp, mA, number of cone‐beam projection images used, cone angle, and object size. The influence on reconstruction parameters including interpolation method, reconstruction filter, field of view, matrix size, and slice thickness were also studied. Under certain conditions, the zero‐dimensional NPS (image variance) was used as a quantitative index to compare the influence from different scan parameters, especially the radiation dose. If the total scan dose is changed by linearly changing the total number of projection images while the dose per frame is kept constant, the noise power has a linear relationship with the reciprocal of the total dose. If the total scan dose is changed by linearly changing the dose per frame while the total number of projection images is kept constant, the noise power has a quadratic relationship with the reciprocal of the total dose. With the same amount of total dose, using fewer projection images results in lower image noise power in the CT image. Quantitative results from this noise power analysis provide guidance for the bCT system operation, optimization, and data reconstruction.