bluuebunny/crossref_metadata_2025 huggingface dataset:
A case study on Bangka Island, Indonesia on the habits and consequences of pesticide use in pepper plantations
Authors: Wiratno  , Taniwiryono Darmono , Van den Brink Paul J. , Rietjens Ivonne M. C. M. , Murk Albertinka J.
Published: July 2007

Habits and consequences of pesticide use in pepper plantations were studied in Indonesia. The first study was conducted by questioning 117 farmers about their habits in pesticide use and determining pesticide residues on pepper berries on Bangka Island. Meanwhile, the second study was completed by analyzing exposure levels of pesticide in farmers' bodies before and after pesticide application to pepper plantations at Sukamulya, West Java. Risks of pesticide exposure to below ground terrestrial invertebrates and aquatic ecosystems adjacent to the treated fields were evaluated using scenarios and a decision support system. Results showed that five respondents (4.3%) were agricultural workers without their own plantations and the others were plantation owners. About 112 respondents (95.7%) used pesticides regularly, while 21 respondents (17.9%) had experienced pesticide poisoning. About 54 respondents (46.2%) tended to apply the same pesticide on all occasions, and 104 respondents (88.9%) indicated to always apply a single compound. About 91 respondents (77.8%) were not aware of the possible impact of pesticides on their health, and 102 respondents (87.2%) were not aware of the possible effects on the environment. In addition while spraying pesticides 17 respondents (14.5%) were smoking, 81 respondents (69.2%) were wearing daily clothes, and 84 respondents (71.8%) were throwing empty bottles into the forest. Exposure study revealed that the residues in the urine and blood increased 6.5–10 and 1.1–1.5 folds, respectively indicating actual and direct exposures. The environmental risk assessment indicated low risks for the terrestrial below ground invertebrates but high potential risks for the aquatic ecosystem. The residues of the major pesticides were below the maximum residue limits. This study indicated that the farmers and their workers, and probably also the environment, were at risk of high exposure to the pesticides applied, but that the risks for the consumers were negligible, if present at all. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 405–414, 2007.
Transfrontal three‐dimensional visualization of midline cerebral structures
Authors: Viñals F. , Muñoz M. , Naveas R. , Giuliano A.
Published: July 2007

Objective To compare sonographic visualization of midline cerebral structures obtained by two‐dimensional (2D) imaging and three‐dimensional (3D) multiplanar and volume contrast imaging in the coronal plane (VCI‐C), with transfrontal 3D acquisition.

Methods Sixty consecutive healthy fetuses in vertex presentation at a mean gestational age of 24 (range, 20–33) weeks underwent 2D and 3D ultrasound examination. Sagittal cerebral planes were reconstructed using 3D acquisition from axial planes by multiplanar analysis and by VCI‐C. The reconstructed midline images of both these techniques were compared with the midline structures visualized directly in the A‐plane by transfrontal 3D acquisition using a sweep angle of 30°. Measurement of the corpus callosum and cerebellar vermis and visualization of the fourth ventricle and the main vermian fissures were compared. The sharpness of the images was also assessed qualitatively. Mid‐sagittal tomographic ultrasound imaging (TUI) was also performed. 3D planes were compared with 2D transfontanelle median planes obtained by transabdominal or, when required, transvaginal sonography.

ResultsThe midline plane could be obtained in 88% of multiplanar, 82% of VCI‐C and 87% of transfrontal analyses. Measurements of the corpus callosum and cerebellar vermis obtained by 3D median planes were highly correlated. The clearest and sharpest definition of midline structures was obtained with transfrontal acquisition. Primary and secondary fissures of the cerebellar vermis could be detected in 13–26% of multiplanar, 18–35% of VCI‐C and 52–79% of transfrontal analyses. 2D visualization was superior or equal to the 3D transfrontal approach in all the parameters compared.

Conclusion 3D planes obtained from axial acquisitions are simpler and easier to display than are transfrontal ones. However, artifacts and acoustic shadowing are frequent in 3D axial acquisition and spatial resolution is better in the direct visualization transfrontal technique. If the standard examination includes a view of the fetal facial profile, a quick 3D acquisition through the frontal sutures provides direct visualization for assessment of the midline structures. We believe that this volumetric methodology could represent a step towards incorporating a comprehensive fetal neuroscan into routine targeted organ evaluation. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Childhood body mass index gain during the summer versus during the school year
Authors: Downey Douglas B. , Boughton Heather R.
Published: July 2007

The nationwide increase in obesity affects all population sectors, but the impact on children is of special concern because overweight children are prone to becoming overweight adults. Contrary to the opinion of experts, research suggests that schools may be more part of the solution than the problem. Recent seasonal comparison research (comparing children's outcomes during the summer and during school year) reports that children gain body mass index (BMI) nearly twice as fast during the summer as during the school year. Whereas most children experience healthier BMI gain during the school year than the summer, this is especially the case for black and Hispanic children and for children already overweight.
Summer programming in rural communities: Unique challenges
Authors: Phillips Ruthellen , Harper Stacey , Gamble Susan
Published: July 2007

During the past several decades, child poverty rates have been higher in rural than in urban areas, and now 2.5 million children live in deep poverty in rural America. Studies indicate that poor children are most affected by the typical “summer slide.” Summer programming has the ability to address the issues of academic loss, nutritional loss, and the lack of safe and constructive enrichment activities. However, poor rural communities face three major challenges in implementing summer programming: community resources, human capital, and accessibility. The success of Energy Express, a statewide award‐winning six‐week summer reading and nutrition program in West Virginia, documents strategies for overcoming the challenges faced by poor, rural communities in providing summer programs. Energy Express (1) uses community collaboration to augment resources and develop community ownership, (2) builds human capital and reverses the acknowledged brain drain by engaging college students and community volunteers in meaningful service, and (3) increases accessibility through creative transportation strategies. West Virginia University Extension Service, the outreach arm of the land‐grant institution, partners with AmeriCorps, a national service program, and various state and local agencies and organizations to implement a program that produces robust results.
Finding the resources for summer learning programs
Authors: Sundius M. Jane
Published: July 2007

Research on summer learning losses has unambiguous implications for America: all children need learning opportunities in the summer. But how and when policymakers, educators, and youth service providers will fashion appropriate programming are far less clear. At the root of this problem is the need to vastly increase, stabilize, and coordinate resources for summer programming. Jane Sundius first outlines the current landscape of summer programs. She then goes on to make the case that two key strategies are necessary to securing sustainable increases in funding that will allow all children access to summer programming. The first is a national advocacy and public will‐building campaign. The second is extensive, local, public‐private planning to map existing summer resources and needs and to create blueprints for programming that serve all children in communities. Drawing on her experiences as a foundation program director, Sundius urges programs, foundation officials, and other stakeholders to expand their summer funding efforts beyond individual summer programs and to support, in addition, strategic communications and community planning efforts that are aimed at providing summer learning opportunities for all children.
The essential role of tree-fern trunks in the regeneration of Weinmannia tinctoria in rain forest on Réunion, Mascarene Archipelago
Authors: Derroire Géraldine , Schmitt Laurent , Rivière Jean-Noël , Sarrailh Jean-Michel , Tassin Jacques
Published: July 2007

The regeneration processes and the spatial distribution of the shade-intolerant Weinmannia tinctoria seedlings in the south of Réunion were investigated, with a special focus on the role of tree-ferns in seedling establishment. Mature individuals and seedling patches of Weinmannia tinctoria, and also tree-ferns, were mapped on two 1-ha rain-forest plots. Weinmannia tinctoria has hemi-epiphytic behaviour since seedlings were generally located on plant supports (99.6%). Regeneration was better on a support than on the ground, and germination tests showed that seeds were light-stimulated. Tall tree-ferns (Cyathea spp.) were suitable supports. Cyathea glauca and C. excelsa were more suitable supports than C. borbonica. Weinmannia tinctoria establishment complies with the facilitation model of succession and is dependent on tree-ferns.

La régénération et la distribution spatiale des semis de Weinmannia tinctoria, espèce intolérante à l'ombre, ont été étudiées dans le sud de La Réunion. Nous nous sommes intéressés au rôle des fougères arborescentes sur l'émergence de plantules. Les adultes matures et les taches de semis (ensembles de plusieurs plantules) de Weinmannia tinctoria, de même que les fougères arborescentes, ont été cartographiés sur deux parcelles de 1 ha en forêt humide. Weinmannia tinctoria a un comportement hémi-épiphyte car les semis se situaient principalement sur des supports (99,6%). La régénération se révélait meilleure sur les supports qu'au sol, et les tests de germination ont montré que les semences germaient mieux à la lumière. Les grandes fougères arborescentes (Cyathea spp.) constituaient des supports privilégiés. Cyathea glauca et Cyathea excelsa représentaient des supports plus favorables que Cyathea borbonica. W. tinctoria apparaît donc comme une espèce qui s'installe principalement en utilisant le modèle de facilitation et qui dépend de la présence de fougères arborescentes.
Uncertainty in hydrologic modeling: Toward an integrated data assimilation framework
Authors: Liu Yuqiong , Gupta Hoshin V.
Published: July 2007

Despite significant recent developments in computational power and distributed hydrologic modeling, the issue of how to adequately address the uncertainty associated with hydrological predictions remains a critical and challenging one. This issue needs to be properly addressed for hydrological modeling to realize its maximum practical potential in environmental decision‐making processes. Arguably, the key to properly addressing hydrologic uncertainty is to understand, quantify, and reduce uncertainty involved in hydrologic modeling in a cohesive, systematic manner. Although general principles and techniques on addressing hydrologic uncertainty are emerging in the literature, there exist no well‐accepted guidelines about how to actually implement these principles and techniques in various hydrologic settings in an integrated manner. This paper reviews, in relevant detail, the common data assimilation methods that have been used in hydrologic modeling to address problems of state estimation, parameter estimation, and system identification. In particular, the paper discusses concepts, methods, and issues involved in hydrologic data assimilation from a systems perspective. An integrated hierarchical framework is proposed for pursuing hydrologic data assimilation in several progressive steps to maximally reduce uncertainty in hydrologic predictions.
Direction of arrival estimation for nonuniform linear arrays by using array interpolation
Authors: Tuncer T. E. , Yasar T. K. , Friedlander B.
Published: July 2007

A new approach is proposed for DOA estimation in nonuniform linear arrays (NLA) based on array interpolation. A Wiener formulation is presented to improve the condition number of the mapping matrix as well as the performance for noisy observations. Noniterative and iterative methods for DOA estimation are proposed. These methods use an initial DOA which is then significantly improved by the subsequent processing. Partially augmentable nonredundant arrays (PANA) and partly filled NLA (PFNLA) are considered and initial DOA is found in a different manner for each of these arrays. PANA are used for noncoherent sources whereas PFNLA are employed when the sources are coherent. Array interpolation is used to map the sample covariance matrix of the NLA to the covariance matrix of a uniform linear array (ULA) with the same aperture size and root‐MUSIC is employed as a fast subspace algorithm for DOA estimation. Proposed methods overcome some of the limitations of the conventional array interpolation. DOA estimation problem is considered for correlated and coherent sources. Proposed approaches are compared with two previous methods as well as the spectral MUSIC and root‐MUSIC algorithms applied on the NLA and ULA, respectively. It is shown that DOA performance is significantly improved for a wide variety of DOA scenarios.
A concentric circle model of multivesicular body cargo sorting
Authors: Nickerson Daniel P , Russell Matthew R G , Odorizzi Greg
Published: July 2007

Targeting of ubiquitylated transmembrane proteins into luminal vesicles of endosomal multivesicular bodies (MVBs) depends on their recognition by endosomal sorting complexes required for transport (ESCRTs), which are also required for MVB vesicle formation. The model originally proposed for how ESCRTs function succinctly summarizes much of the protein–protein interaction and genetic data but oversimplifies the coordination of cargo recognition and cannot explain why ESCRTs are required for the budding of MVB vesicles. Recent structural and functional studies of ESCRT complexes suggest an alternative model that might direct the next series of breakthroughs in understanding protein sorting through the MVB pathway.
Statins and clinical outcomes in heart failure
Authors: Martin Jennifer H. , Krum Henry
Published: July 2007

HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) reductase inhibitors (statins) are well-established therapies in the prevention and treatment of cardiovascular disease, reducing all-cause mortality and cardiovascular events in many disease states. Studies have also suggested that statins given to patients after myocardial infarction improve event-free survival even in short time frames; however, evidence for the benefit of statins in established HF (heart failure) has not been demonstrated with the same rigour of a randomized clinical trial setting. In fact, clinical data examining the effect of statins in HF have been limited by the retrospective or observational nature of these analyses, examination of incompletely validated surrogate end points, small prospective studies in subgroups of HF subjects, and non-uniform doses and different statins being used. In this review, we examine the evidence for the effect of statins on mortality in HF, taking into account theoretical arguments, appropriateness of surrogate markers, animal data and analysis of the predominantly retrospective clinical data that is currently available.
Variation of Microfibril Angle Between Four Provenances of Sitka Spruce (Picea sitchensis [Bong.] Carr.)
Authors: Vainio U. , Andersson S. , Serimaa R. , Paakkari T. , Saranpää P. , Treacy M. , Evertsen J.
Published: July 2007

Abstract: The mean microfibril angle (MFA) of tracheids in Sitka spruce (Picea sitchensis [Bong.] Carr.) from four provenances was determined by X‐ray diffraction. Seeds were from four locations in North America: California, Oregon, Queen Charlotte Islands and Washington. Transplants were planted in 1976 and grown in Ireland (Shillelagh Forest). The mean MFA close to the pith was ca. 22° and decreased to ca. 11° in the outer rings. It was found that the MFA varies strongly not only as a function of the annual ring and the distance from pith but also as a function of the seed origin. Trees of California and Queen Charlotte Islands provenance had a larger mean MFA in general than trees of Washington and Oregon provenance. Also, the shapes of the cell cross sections were determined to some extent from the diffraction patterns. For samples of California and Washington provenance the average thickness of the cellulose crystallites was determined to be about 3.0 nm.
Callose in Frankia‐Infected Tissue of Datisca glomerata is an Artifact of Specimen Preparation
Authors: Jacobsen K. R. , Berry A. M.
Published: July 2007

Abstract: Callose, or β‐1,3‐glucan, is a plant cell wall polysaccharide that occurs endogenously at distinct sites in a variety of tissues. Callose is also formed in response to stress involving cell membrane perturbation. In sections of chemically‐fixed nodule tissue of the actinorhizal host, Datisca glomerata, callose was cytochemically detected within the Frankia‐infected cortical cells, as an extensive network of wall material surrounding the microsymbiont, but not in uninfected cortical cells. Callose formation was completely inhibited within the infected cells when 2‐deoxy‐D‐glucose, an inhibitor of callose formation, was included in the tissue fixative. The study concludes that callose deposition in the Datisca nodule infected zone is apparently a stress response to tissue preparation and fixation. However, the rapidity and extent of callose deposition primarily at the symbiotic interface in Frankia‐infected cells suggests an unusual predisposition to biosynthesis of β‐1,3‐glucan in the nodule cortical cells that is related to their interaction with the microsymbiont.
Photosynthesis in Salsola Species (Chenopodiaceae) from Southern Africa Relative to their C4 Syndrome Origin and their African‐Asian Arid Zone Migration Pathways
Authors: Pyankov V. , Black C. , Stichler W. , Ziegler H.
Published: July 2007

Abstract: Over 60 Salsola species of Chenopodiaceae from South Africa were studied for their photosynthesis type, using δ13C analysis and light microscopy of leaf anatomy. These species cover about 70 % of the total list of Southern African Salsola species and grow naturally in South and Southwest African desert regions. All species are shrubby forms and belong to the single subsection Caroxylon. Only C4 photosynthesis was found in the Salsola species determined with 13C/12C carbon isotope discrimination values that ranged from ‐ 11.04 to ‐ 14.03 % (PDB), plus the presence of a Kranz type assimilation tissue anatomy. The apparent absence of C3 in Salsola in South and Southwest Africa and the known presence of C3 and C3 ‐ C4 intermediate photosynthesis in Caroxylon, Salsola species in Asia strongly indicate that the genus Salsola originated in Asia and later migrated to South Africa.
Lipoxygenase Pathway and Membrane Permeability and Composition during Storage of Potato Tubers (Solanum tuberosum L. cv Bintje and Désirée) in Different Conditions
Authors: Fauconnier M.‐L. , Rojas‐Beltrán J. , Delcarte J. , Dejaeghere F. , Marlier M. , du Jardin P.
Published: July 2007

Abstract: Potato tubers (Solanum tuberosum L. cv Bintje and Désirée) were stored for 12 months under three different storage conditions: 4 °C, 20 °C with sprout inhibitor and 20 °C without sprout inhibitor. Independent of the storage conditions, our results show that the increase of membrane permeability, as revealed by electrolyte leakage, is not correlated with the lipid saturation status. Moreover, there is no simple correlation between cold sweetening and membrane permeability or lipid saturation status. During storage at 20 °C without sprout inhibitor, the increase in membrane permeability is inversely correlated to sucrose accumulation, but this is not the case when tubers were stored with sprout inhibitors. Lipoxygenase (LOX) is often proposed as responsible for peroxidative damage to membrane lipids. The gradual peroxidation resulting in double bond index decrease is regarded as a cause of senescence sweetening. Our results revealed that the role of LOX in aging and senescence of potato tubers is far from clear. LOX activity and gene expression are not correlated with the fatty acids composition of the membrane. Moreover, LOX activity and fatty acid hydroperoxide content are low in older tubers, whatever the storage conditions or the varieties. On the basis of our results, the correlation between sugar accumulation (low temperature and senescence sweetening) and peroxidative damage occurring during storage of potato tubers is discussed.
Breakup behavior of a conducting drop suspended in a viscous fluid subject to an electric field
Authors: Dubash Neville , Mestel A. Jonathan
Published: July 2007

The slow axisymmetric deformation of a conducting drop surrounded by a viscous insulating fluid subject to a uniform electric field is considered. Numerical computations, based on a boundary integral formulation, are used to follow the behavior of relatively inviscid and viscous drops right up to breakup. The type of breakup seen depends on the ratio of the viscosity of the drop to that of the surrounding fluid, and on the electric field strength. The different types of breakup possible are small droplets being emitted from the ends of the drop with a charge greater than the Rayleigh limit, the formation of what appear to be pointed ends with the subsequent ejection of thin jet-like structures, or the formation of thin jet-like structures without the pointed ends. The different types of breakup are examined and the different regions of the parameter space where each occurs is determined. Also, by considering different stress balances, local equilibrium solutions that allow for a conical drop end are derived. Several sets of solutions, corresponding to different stress balances, are found. However, none of the conical end solutions appear to be compatible with the pointed ends seen in the numerical results.
Statistical mechanical theory for steady state systems. VII. Nonlinear theory
Authors: Attard Phil
Published: July 2007

The second entropy theory for nonequilibrium thermodynamics is extended to the nonlinear regime and to systems of mixed parity (even and odd functions of molecular velocities). The steady state phase space probability density is given for systems of mixed parity. The nonlinear transport matrix is obtained and it is shown to yield the analog of the linear Onsager-Casimir reciprocal relations. Its asymmetric part contributes to the flux and to the production of second entropy. The nonlinear transport matrix is not simply expressible as a Green-Kubo fluctuation equilibrium time correlation function. However, here the first nonlinear correction to the transport coefficient is given explicitly as a type of the Green-Kubo equilibrium time correlation function. The theory is illustrated by application to chemical kinetics.
Preferred conformation of the glycosidic linkage of methyl-β-mannose
Authors: Coskuner Orkid
Published: July 2007

The conformational preference of the glycosidic linkage of methyl-β-mannose was studied in the gas phase and in aqueous solution by ab initio calculations, and by molecular dynamics (MD) and Car-Parrinello molecular dynamics (CPMD) simulations. MD simulations were performed with various water potential functions to study the impact of the chosen water potential on the predicted conformational preference of the glycosidic linkage of the carbohydrate in solution. This study shows that the trans (t) orientation of the glycosidic linkage of methyl-β-mannose is preferred over its gauche clockwise (g+) orientation in solution. CPMD simulations clearly indicate that this preference is due to intermolecular hydrogen bonding with surrounding water molecules, whereas no such information could be demonstrated by MD simulations. This study demonstrates the importance of ab initio molecular dynamics simulations in studying the structural properties of carbohydrate-water interactions.
Dissociative recombination study of N3+: Cross section and branching fraction measurements
Authors: Zhaunerchyk V. , Geppert W. D. , Vigren E. , Hamberg M. , Danielsson M. , Larsson M. , Thomas R. D. , Kaminska M. , Österdahl F.
Published: July 2007

We report an investigation into the dissociative recombination of the azide radical cation, N3+. The reaction rate constant has been measured to be 6.47×10−7cm3s−1 at room temperature. This value is smaller than those reported earlier for the ion-electron neutralization of N3+ at nitrogen atmospheric pressure. A strong propensity to dissociate through the N2+N channel has been observed.
Effect of pattern topology on the self-cleaning properties of textured surfaces
Authors: Zhang Xueyun , Kong B. , Tsui O. K. C. , Yang X. , Mi Y. , Chan C. M. , Xu B.
Published: July 2007

The water contact angle and self-cleaning property of microfabricated surface textures possessing different topologies are compared. In one kind of surface textures, the protruded regions form a connected square network. In the other kind of surface textures, the protruded regions form a regular array of square posts. We find that the water apparent contact angle of the connected textures agrees with the Cassie equation [Discuss. Faraday Soc. 3, 11 (1948)], but that of the disconnected textures is much larger. Nevertheless, the disconnected textures exhibit inferior self-cleaning property, contrary to conventional conception. We discuss the possible reasons for these observations.
Niobium doped TiO2: Intrinsic transparent metallic anatase versus highly resistive rutile phase
Authors: Zhang S. X. , Kundaliya D. C. , Yu W. , Dhar S. , Young S. Y. , Salamanca-Riba L. G. , Ogale S. B. , Vispute R. D. , Venkatesan T.
Published: July 2007

We report on the structural, electrical, and optical properties of 5% niobium doped TiO2 thin films grown on various substrates by pulsed laser deposition. The epitaxial anatase Nb:TiO2 film on LaAlO3 is shown to be an intrinsic transparent metal and its metallic property arises from Nb substitution into Ti site as evidenced by the Rutherford backscattering channeling result. In contrast, the rutile Nb:TiO2 thin films show insulating behaviors with 2–3 orders higher room temperature electrical resistivity and ∼30 times lower mobility. A blueshift in the optical absorption edge is observed in both phases, though of differing magnitude.
Universal off-axis light transmission properties of the bright state in perfectly compensated liquid crystal devices
Authors: Jang Yong-Kyu , Bos Philip
Published: July 2007

We studied the off-axis light transmission characteristics of the bright state of common liquid crystal device modes. The dark state of these device modes is optically compensated to have minimum light transmittance at all angles. Our research shows there is an unexpected universal shape of the off-axis light transmission value in its bright state, regardless of what liquid crystal mode is used. To understand this surprising fact, we consider simple dark and bright state models in terms of phase retardation and transmittance.
Carbon nanochannels elaborated by buckle delamination control on patterned substrates
Authors: Tranchant J. , Angleraud B. , Han X. L. , Landesman J. P. , Tessier P. Y.
Published: July 2007

Carbon nanochannels were achieved using lithographically patterned lines on a silicon substrate as a template to control the buckle delamination of highly equibiaxial compressively stressed thin films. Carbon films were synthesized by ionized physical vapor deposition through inductively coupled plasma magnetron sputtering. The obtained structures exhibit dimensions as small as 500nm wide and 80nm high, and may be used in nanofluidic applications. Results regarding the characterization of their growth mechanism and structural analyses by Raman microspectroscopy are presented.
Absence of long-range Ni∕Mn ordering in ferromagnetic La2NiMnO6 thin films
Authors: Singh M. P. , Grygiel C. , Sheets W. C. , Boullay Ph. , Hervieu M. , Prellier W. , Mercey B. , Simon Ch. , Raveau B.
Published: July 2007

Epitaxial La2NiMnO6 thin films have been grown on (001)-orientated SrTiO3 using the pulsed laser deposition technique. The thin film samples are semiconducting and ferromagnetic with a Curie temperature close to 270K, a coercive field of 920Oe, and a saturation magnetization of 4.85μB/formula unit. Transmission electron microscopy, conducted at room temperature, reveals a majority phase having an “I-centered” structure with a≈c≈asub2 and b≈2asub along with minority phase domains having a “P-type” structure (asub being the lattice parameter of the cubic perovskite structure). A discussion on the absence of Ni∕Mn long-range ordering, in light of recent literature on the ordered double-perovskite La2NiMnO6 is presented.
Optical quenching of NiO∕Ni coated ZnO nanowires
Authors: Park Y. H. , Shin Y. H. , Noh S. J. , Kim Yongmin , Lee S. S. , Kim C. G. , An K. S. , Park C. Y.
Published: July 2007

Low temperature photoluminescence (PL) measurements were carried out to investigate optical transition characteristics of ZnO nanowires, Ni nanodot, and NiO coated ZnO nanowires (NWs). PL emission spectra show emission peaks of distinctive bound exciton to neutral donor (DX0) and to acceptor (AX0) transition. The authors found that the optical quenching was drastic with increasing temperature and the activation energies are unusually small. The major PL emission peak for ZnO NW was switched from DX0 to AX0 for Ni–ZnO nanodot NWs. This is due to the reason that diffused hydrogen atoms into ZnO NWs during thermal annealing played as acceptors.
Radar reveals Mercury’s molten core
Authors: Miller Johanna
Published: July 2007

The answer to a long-standing question about Mercury’s interior sheds new light on the formation of the planet and the origin of its magnetic field.
Quantum oscillations finally seen in high-temperature superconductors
Authors: Levi Barbara Goss
Published: July 2007

The oscillations focus renewed attention on the nature of the Fermi surface near the onset of superconductivity.
The Genesis of the International Geophysical Year
Authors: Korsmo Fae L.
Published: July 2007

The International Geophysical Year of 1957–58 grew out of scientific interests, but also out of national interests, including the postwar reconstruction of Europe. Some say, though, that a chocolate layer cake was what sealed the deal.
What’s wrong with these stanzas?
Authors: Mermin N. David
Published: July 2007

Enough of idle talk and twaddle. Let’s celebrate the standard model.
Rebecca Worthylake: The flooding of science
Authors: LeBrasseur Nicole
Published: July 2007

Starting up a brand new lab is difficult enough. But when a hurricane soon forces you thousands of miles from your new research home, a whole new layer of complications arises, as Rebecca Worthylake recently found.
Subcompartments of the macrophage recycling endosome direct the differential secretion of IL-6 and TNFα
Authors: Manderson Anthony P. , Kay Jason G. , Hammond Luke A. , Brown Darren L. , Stow Jennifer L.
Published: July 2007

Activated macrophages secrete an array of proinflammatory cytokines, including tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6), that are temporally secreted for sequential roles in inflammation. We have previously characterized aspects of the intracellular trafficking of membrane-bound TNFα and its delivery to the cell surface at the site of phagocytic cups for secretion (Murray, R.Z., J.G. Kay, D.G. Sangermani, and J.L. Stow. 2005. Science. 310:1492–1495). The trafficking pathway and surface delivery of IL-6, a soluble cytokine, were studied here using approaches such as live cell imaging of fluorescently tagged IL-6 and immunoelectron microscopy. Newly synthesized IL-6 accumulates in the Golgi complex and exits in tubulovesicular carriers either as the sole labeled cargo or together with TNFα, utilizing specific soluble NSF attachment protein receptor (SNARE) proteins to fuse with the recycling endosome. Within recycling endosomes, we demonstrate the compartmentalization of cargo proteins, wherein IL-6 is dynamically segregated from TNFα and from surface recycling transferrin. Thereafter, these cytokines are independently secreted, with TNFα delivered to phagocytic cups but not IL-6. Therefore, the recycling endosome has a central role in orchestrating the differential secretion of cytokines during inflammation.
Intermediate filament scaffolds fulfill mechanical, organizational, and signaling functions in the cytoplasm
Authors: Kim Seyun , Coulombe Pierre A.
Published: July 2007

Intermediate filaments (IFs) are cytoskeletal polymers whose protein constituents are encoded by a large family of differentially expressed genes. Owing in part to their properties and intracellular organization, IFs provide crucial structural support in the cytoplasm and nucleus, the perturbation of which causes cell and tissue fragility and accounts for a large number of genetic diseases in humans. A number of additional roles, nonmechanical in nature, have been recently uncovered for IF proteins. These include the regulation of key signaling pathways that control cell survival, cell growth, and vectorial processes including protein targeting in polarized cellular settings. As this discovery process continues to unfold, a rationale for the large size of this family and the context-dependent regulation of its members is finally emerging.
Pimet, the Drosophila homolog of HEN1, mediates 2′-O-methylation of Piwi- interacting RNAs at their 3′ ends
Authors: Saito Kuniaki , Sakaguchi Yuriko , Suzuki Takeo , Suzuki Tsutomu , Siomi Haruhiko , Siomi Mikiko C.
Published: July 2007

Piwi-interacting RNAs (piRNAs) consist of a germline-specific group of small RNAs derived from distinct intergenic loci in the genome. piRNAs function in silencing selfish transposable elements through binding with the PIWI subfamily proteins of Argonautes. Here we show that piRNAs in Drosophila are 2′-O-methylated at their 3′ ends. Loss of Pimet (piRNA methyltransferase), the Drosophila homolog of Arabidopsis HEN1 methyltransferase for microRNAs (miRNAs), results in loss of 2′-O-methylation of fly piRNAs. Recombinant Pimet shows single-stranded small RNA methylation activity in vitro and interacts with the PIWI proteins within Pimet mutant ovary. These results show that Pimet mediates piRNA 2′-O-methylation in Drosophila.
High-Resolution, Intravital 4D Confocal Time-Lapse Imaging in Avian Embryos Using a Teflon Culture Chamber Design: Figure 1.
Authors: Rupp Paul A. , Kulesa Paul M.
Published: July 2007

INTRODUCTION

Cell migration is a key aspect of many developmental processes, yet there are relatively few whole-vertebrate embryo culture systems that allow for intravital, high-resolution optical imaging of cell movements, cell-cell interactions, and cell-matrix interactions. Here, we present a protocol for 4D (3D + time), high-resolution confocal imaging of fluorescently labeled cells within living avian embryos. We discuss the culture chamber assembly and interface with a commercially available microscope-stage culture-dish heating system. To demonstrate how the system works, we describe the protocol in use with chick embryos while following individual fluorescently labeled neural crest cells, a major migratory cell population that sorts into complex patterns of discrete streams. By combining the embryo culture directly on glass with confocal 4D time-lapse imaging, we demonstrate that individual neural crest cell migratory behaviors and cell-cell interactions may be visualized for short periods of time (<6 h). This technique can be adapted to study other migratory cell populations or developmental events in whole avian embryos.
A paracrine role for chemoattractant receptor‐homologous molecule expressed on T helper type 2 cells (CRTH2) in mediating chemotactic activation of CRTH2+ CD4+ T helper type 2 lymphocytes
Authors: Vinall Shân L. , Townsend Elizabeth R. , Pettipher Roy
Published: July 2007

Summary Activation of human CRTH2+ CD4+ T helper type 2 (Th2) cells with anti‐CD3/anti‐CD28 led to time‐dependent production of prostaglandin D2 (PGD2) which peaked at 8 hr. The production of PGD2 was completely inhibited by cotreatment with the cyclo‐oxygenase inhibitor diclofenac (10 μm) but was not affected by cotreatment with ramatroban, a dual antagonist of both the thromboxane‐like prostanoid (TP) receptor and the chemoattractant receptor‐homologous molecule expressed on Th2 cells (CRTH2). Supernatants from activated CRTH2+ CD4+ Th2 cells caused a concentration‐dependent increase in the migration of naive CRTH2+ CD4+ Th2 cells compared to supernatants from unstimulated CRTH2+ CD4+ Th2 cells. The level of chemotactic activity peaked at 8 hr after activation, corresponding to the peak levels of PGD2, but production of chemotactic activity was only partially inhibited by the cyclo‐oxygenase inhibitor diclofenac. In contrast, ramatroban completely inhibited the chemotactic responses of naive Th2 cells to supernatants from activated CRTH2+ CD4+ Th2 cells collected up to 8 hr after activation, although supernatants collected 24 hr after activation were less sensitive to inhibition by ramatroban. The selective TP antagonist SQ29548 did not inhibit migration of Th2 cells, implicating CRTH2 in this response. These data suggest that CRTH2 plays an important paracrine role in mediating chemotactic activation of Th2 cells. Interestingly, although PGD2 is produced from Th2 cells and contributes to this paracrine activation, it appears that additional CRTH2 agonist factors are also produced by activated Th2 cells and the production of these factors occurs independently of the cyclo‐oxygenase pathway of the arachidonic acid metabolism.
Socio‐economic deprivation associated with acute rheumatic fever. A hospital‐based case‐control study in Bangladesh
Authors: Zaman Mohammad Mostafa , Yoshiike Nobuo , Chowdhury Anisul Haque , Jalil Md. Qumrul , Mahmud Razia Sultana , Faruque Gnulam Mohammed , Rouf Mian Abdur , Haque K.M.H.S. Sirajul , Tanaka Heizo
Published: July 2007

There are few studies on the relationship between socioeconomic factors and rheumatic fever (KF) in the populations where the burden of both socio‐economic deprivation and RF is still very high. The aim of this study is to assess the association between some socio‐economic factors and RF by examining data available from a RF hospital in Bangladesh. We have reviewed the medical records of patients presenting with manifestations suggestive of RF during a 1‐year period. From the patients who showed group A beta‐haemolytic streptococcal upper respiratory infection (ABHS infection), 44 RF cases defined by the Jones criteria and 86 control subjects, who did not satisfy the criteria, were identified for analysis. The median age was 12 years and 60% were female. RF was significantly associated with low income (odds ratio [OR] 2.37; P= 0.04); poor living conditions: substandard (kacha) house (OR 2.93, P= 0.02); and poor nutritional status: low height for age (OR 2.68, P= 0.02). Multiple logistic regression analysis revealed an increased OR for kacha house (OR 3.18, P= 0.02) but the same estimate for low height for age (OR 2.68; P= 0.04). Our analysis shows that, among the patients presenting to the RF hospital with proven ABHS infection, acute RF is associated with socio‐economic deprivation.
Sociodemographic and educational correlates of hearing loss in Hispanic children
Authors: Lee David J. , Gomez‐Marin Orlando , Lee Heidi M.
Published: July 2007

Sociodemographic and educational correlates of hearing loss were examined in Cuban‐American, Mexican‐American and Puerto Rican children 6–19 years of age. Logistic regression analyses indicated a greater risk of bilateral hearing loss among children living in crowded housing conditions or without health insurance, as well as among those who were below expected school grade level and whose parents reported low educational attainment levels. However, the strengths of these associations were small to moderate in magnitude and were not always consistent across the ethnic subgroups. These findings provide some evidence that hearing‐impaired Hispanic children are more likely to reside in economically disadvantaged families and to be below their expected school grade level.
Recruitment, retention and characteristics of women in a prospective study of preconceptional risks to reproductive outcomes: experience of the Diana Project
Authors: Brown Judith E. , Jacobs David R. , Barosso Geralyn M. , Potter John D. , Hannan Peter J. , Kopher Richard A. , Rourke Mary Jo , Hartman Terryl J. , Hase Kirsten
Published: July 2007

Preterm delivery, low birthweight, and intrauterine growth retardation are common and recalcitrant problems in many countries. Although much remains to be learned, we know particularly little about the relationships between preconceptional and early pregnancy exposures and these and other reproductive outcomes. The study presented here was primarily designed to investigate the relationships between nutritional exposures measured before and during pregnancy and reproductive outcomes. This paper describes methods used to recruit the required 1000 preconceptional women from the collaborating health maintenance organisation (HMO) and the retention of participants in this rime‐intensive study. The results presented demonstrate that an adequate completion rate (66.3%), and a remarkably representative sample of women that poses few threats to the study's validity, can be obtained by population‐based recruitment of women from an HMO.
Transmission of toxoplasmosis in two renal allograft recipients receiving an organ from the same donor
Authors: Rogers N.M. , Peh C.‐A. , Faull R. , Pannell M. , Cooper J. , Russ G.R.
Published: July 2007

Abstract: Toxoplasma gondii is a ubiquitous protozoan parasite. After acute infection it continues to exist as cysts in the muscles and brain. Recipients of organ allografts are susceptible to the disease as a result of reactivation of quiescent infection either by transmission from the organ donor or by consumption of undercooked meat. We describe 2 cases of fatal toxoplasmosis in renal allograft recipients who received their organs from the same cadaveric donor. Both recipients died 5 weeks after renal transplantation, within days of each other. Multiorgan involvement with toxoplasmosis was demonstrated at autopsy. No evidence of the parasite was found in the transplanted kidney, either at the time of insertion or at autopsy. Neither recipient had serologic evidence of previous exposure to T. gondii. The donor had positive IgG but indeterminate IgM antibodies suggesting acute infection at the time of death; there was no clinical suspicion that the donor died from acute toxoplasmosis. We conclude that toxoplasmosis was transmitted by the donor kidneys. In an attempt to minimize the possibility of future transmission, donors are now tested for anti‐toxoplasma IgM antibodies and recipients are treated with trimethoprim/sulfamethoxazole for the first 6 months after renal transplantation.
Factors influencing varicella zoster virus infection after allogeneic peripheral blood stem cell transplantation: low‐dose acyclovir prophylaxis and pre‐transplant diagnosis of lymphoproliferative disorders
Authors: Kim D.H. , Messner H. , Minden M. , Gupta V. , Kuruvilla J. , Wright J. , Lipton J.
Published: July 2007

Abstract: Varicella zoster virus (VZV) infection is one of the frequent opportunistic infections after allogeneic bone marrow transplantation, with a high incidence of 30–50%. However, no data have been reported on VZV infection after allogeneic peripheral blood stem cell transplantation (PBSCT).

Patients and methods. We report a retrospective analysis of VZV infection in 192 allogeneic PBSCT recipients. Twenty‐seven patients (14%) received long‐term prophylaxis of low‐dose acyclovir (200 mg twice daily orally ≥3 months) for recurrent oral (n=21) or genital herpes simplex virus infection (n=5) or for a previous history of recurrent VZV infection (n=1).

Results. Forty‐two patients (22%) developed VZV infections: localized (n=37) and disseminated infection (n=5). The incidence of VZV infection at 1 and 3 years was 19.3±3.3% and 36.8±5.2%, respectively. Complications included post‐herpetic neuralgia (n=18, 43%), secondary bacterial infections (n=3), and intracranial hemorrhage (n=1) with 2 deaths. A higher risk factor for VZV infection was pre‐transplant diagnosis of a lymphoproliferative disorder (LPD): chronic lymphocytic leukemia, Hodgkin's disease, or non‐Hodgkin's lymphoma (P=0.021, 52.5% in LPD vs. 32.6% in non‐LPD group). The use of low‐dose acyclovir prophylaxis (P=0.043, 14.7% in acyclovir vs. 41.6% in nonacyclovir group) was found to be protective. Although no VZV infection episodes were noted during the period of acyclovir prophylaxis, 3 episodes of VZV infection were noted after acyclovir cessation.

Conclusion. The incidence of VZV infection after PBSCT was high at 36.8%, with patients transplanted for LPDs at higher risk. The long‐term use of low‐dose acyclovir may be protective for VZV infection, although it does not completely prevent rebound of late VZV infection.
Methicillin‐resistant Staphylococcus aureus infection after living‐donor liver transplantation in adults
Authors: Hashimoto M. , Sugawara Y. , Tamura S. , Kaneko J. , Matsui Y. , Moriya K. , Koike K. , Makuuchi M.
Published: July 2007

Background. Methicillin‐resistant Staphylococcus aureus (MRSA) infection frequently complicates the postoperative course in deceased‐donor liver transplantation. The incidence and risk factors of MRSA infection after Living‐donor Liver transplantation (LDLT), however, are unclear.

Methods. We retrospectively reviewed the data from 242 adult patients who underwent LDLT at the University of Tokyo Hospital. The microbiologic and medical records of the patients from admission to 3 months after LDLT were reviewed. Uni‐ and multivariate analyses were performed to identify the independent risk factors for postoperative MRSA infection.

Results. Postoperative MRSA infection occurred in 25 of 242 patients by median postoperative day 23. Preoperative MRSA colonization, preoperative use of antimicrobials, operation time (≥16 h), and postoperative apheresis independently predicted postoperative MRSA infection.

Conclusion. Surveillance culture should be checked periodically after admission to identify patients at high risk for MRSA infection and to administer appropriate antimicrobials for perioperative infection. Postoperative apheresis, suggesting postoperative liver dysfunction, predisposed patients to MRSA infection.