bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for protein identification using expressed sequence tags and peptide mass fingerprinting for seed crops without complete genome sequences
Authors: Yang Liming , Luo Yuming , Wei Jifu , Ren Chongmiao , Zhou Xin , He Shaoheng
Published: September 2010

Proteomic approaches based on two-dimensional gel electrophoresis, mass spectrometry and database search are widely used to address questions about the development, physiology and quality of seeds. Identification of proteins is of great importance in proteomic analyses. For seed crops without full genome information, cross-species protein identification by mass spectrometry-driven sequence similarity search can be used. However, this approach is risky due to protein polymorphism between different species. Species-specific expressed sequence tag (EST) databases are an invaluable resource, which complements mass spectrometry data analysis for protein identification. Here, we illustrate a modified method of protein identification and characterization using species-specific EST databases and peptide mass fingerprinting with an example of protein identification. This method is reliable, supplements the existing methods, and improves the efficiency and accuracy of protein identification for seed crops for which complete genome information is not available.
Une dyspnée pas comme les autres, ou quand on parle du loup…
Authors: Gavillet  , Maillard Dewarrat  , Petitpierre  , Vollenweider
Published: September 2010

Wir berichten über einen Patienten mit spätem Beginn eines systemischen Lupus erythematodus, der sich durch eine hämolytische Anämie und eine Pleuritis manifestierte. Es wird auf die klinischen Symptome, Diagnose, Prognose und Therapie des systemischen Lupus im Allgemeinen eingegangen, mit einem speziellem Fokus auf hämatologischen Veränderungen und die Lungenbeteiligung.
Entwicklungsmodelle aggressiv-dissozialen Verhaltens und ihr Nutzen für Prävention und Behandlung
Authors: Scheithauer Herbert , Petermann Franz
Published: September 2010

Es wird ein Überblick über Entwicklungsmodelle aggressiv-dissozialen Verhaltens gegeben. Die meisten Entwicklungsmodelle (z. B. nach Patterson, Moffitt oder Loeber) unterscheiden zwischen Früh- und Spätstartern, zusätzlich arbeiten andere Modelle weitere begrenzte Entwicklungspfade im Kindes- oder Erwachsenenalter heraus. Eine Reihe von aktuellen Ergebnissen führt jedoch dazu, dass die etablierten Modelle und deren Annahmen kritisch zu betrachten sind. Abschließend wird der Nutzen dieser aktuellen Befunde sowie der Entwicklungsmodelle für die Auswahl und erfolgreiche Umsetzung von Präventionen und Interventionen diskutiert.
Zur Komorbidität von aggressivem Verhalten und ADHS
Authors: Witthöft Jan , Koglin Ute , Petermann Franz
Published: September 2010

Bei Kindern und Jugendlichen treten aggressives Verhalten und ADHS häufig gemeinsam auf und führen vielfach zu erheblichen psychosozialen Belastungen. Durch eine Metaanalyse wird eine verlässliche Maßzahl zum komorbiden Auftreten von ADHS und aggressivem Verhalten bestimmt. Anhand der Datenbanken PsycINFO und Pubmed wurden Studien identifiziert, die neben den relevanten Suchbegriffen ausgewählte Einschlusskriterien erfüllten, unter anderem „Allgemeinbevölkerung“ und „strukturierte Interviewverfahren“. In die Berechnung gingen acht epidemiologische Studien ein (N = 29980). Die metaanalytische Betrachtung bestätigt die hohe Komorbidität von ADHS und aggressivem Verhalten mit einem mittleren Odds Ratio von 21. Dieses Ergebnis wird für die Ätiologie und den Krankheitsverlauf diskutiert. Relevante Schlussfolgerungen für Diagnostik und Therapie werden aufgezeigt.
Prävention von Aggression und Gewalt
Authors: Petermann Franz , Lehmkuhl Gerd
Published: September 2010

Studien zeigen, dass es eine beachtliche Zahl von Jugendlichen mit Gewalterfahrung gibt–sowohl in der Rolle des Täters als auch des Opfers. Die hohen finanziellen und psychosozialen Kosten machen es erforderlich, effektive Präventions- und Behandlungsmaßnahmen zu entwickeln, die den individuellen Umständen gerecht werden. Es werden Ansätze zur Aggressionsprävention vorgestellt, die sich zum einen an Kinder, zum anderen an die Eltern und Erzieher richten. Dabei liegt der Schwerpunkt auf der Früherkennung und Prävention aggressiver Verhaltensweisen, um negative Entwicklungsverläufe zu verhindern.
The Person and the Variable in Developmental Psychology
Authors: Bergman Lars R. , Andersson Håkan
Published: September 2010

A brief theoretical and methodological overview is given of the person-oriented and the variable-oriented approach, how these are commonly used in longitudinal research, and what one should take into consideration before choosing either approach. An empirical research example is also given where the association was studied between, on the one hand, attention control – activity level in early adolescence and, on the other hand, persistent versus adolescence-limited criminality. Key topics discussed include properties that variables must have to be suitable for the study of individual pattern development, the problem-method match, and prediction versus understanding.
Source of prolonged bursts of high‐energy gamma rays detected in thunderstorm atmosphere in Japan at the coastal area of the Sea of Japan and on high mountaintop
Authors: Babich Leonid P. , Bochkov Evgenii I. , Donskoi Evgenii N. , Kutsyk Igor M.
Published: September 2010

To analyze whether relativistic runaway electron avalanches (RREAs) are capable of developing inside tropospheric thunderclouds, we carried out numerical simulations in real atmosphere of hard γ ray bursts with a duration of 1 min observed in Japan from thunderclouds at sea level and on high mountaintop, assuming that the bursts originated from a point source of bremsstrahlung produced by RREA. Portions and on‐ground fluence of γ rays reaching the sea level were calculated for various source altitudes h. For fitting the observations at the coast of the Sea of Japan, the source should be localized at altitudes h = 0.5–2 km. The on‐ground γ ray spectra calculated for these source altitudes are close to the spectrum observed at the coast and the spectrum of terrestrial γ ray flashes observed in the near space. The numbers of γ photons emitted by the source at h = 0.5–2 km fitting the γ ray fluence measured at the coast are in the range of 1012–1015. The required RREA enhancement fits the limitation imposed by the relativistic feedback by Dwyer (2003a, 2005, 2007). Both emission and on‐ground γ spectra calculated for the air layer of 70 g cm−2 are close to the γ‐burst spectrum observed at the mountaintop. We numerically predicted the characteristics of neutron pulse that most likely accompanied the γ bursts. The proximity of the emission and observed spectra prove that the γ source was close to the top. As a whole, the results of the simulations testify that RREAs could be responsible for the observed γ bursts and, consequently, that they are capable of developing inside tropospheric thunderclouds.
Insights into an Asian dust event sweeping Beijing during April 2006: Particle chemical composition, boundary layer structure, and radiative forcing
Authors: Wang Weijie , Cheng Tiantao , Zhang Renjian , Jia Xuan , Han Zhiwei , Zhang Xiaoling , Xu Xiaofeng , Li Deping
Published: September 2010

Intense measurements on a giant dust event sweeping over the Asian continent during springtime were conducted in Beijing from 16 to 20 April 2006. Beijing suffered from a large amount of mineral dust transported long range from upwind regions, identified as the desert areas of Mongolia and Inner Mongolia. During the prime time of dust event, hourly PM10 concentrations increased drastically to 1200 μg/m3, corresponding to the lowest visibility of 3 km. The mass concentrations of major crustal elements in aerosols during dusty days were nearly double those of nondusty days. The quasistationary front had great contributions to the formation of severe dusty days over Beijing because of an equiponderant confluence of northern cold air masses from a Siberian anticyclone and southern warm air masses. During the dust event, northeast jets below the convective atmosphere boundary layer occurred at multilevel heights of 50–65 m, 100–160 m, and 160–260 m, with the highest wind speed exceeding 14 m s−1. Humidity inversions usually occurred at heights of 160–240 m, 60–140 m, and 5–30 m due to the cold air horizontal advection. The enhancement of dust loadings in the atmosphere of Beijing during the dust event resulted in a cooling effect by –62.0 W m−2 radiative forcing at the top of atmosphere.
Temporal variations of atomic oxygen in the upper mesosphere from SABER
Authors: Smith Anne K. , Marsh Daniel R. , Mlynczak Martin G. , Mast Jeffrey C.
Published: September 2010

One of the atmospheric constituents that can be retrieved from observations by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere‐Ionosphere‐Mesosphere Energetics and Dynamics (TIMED) satellite is atomic oxygen in the upper mesosphere. Atomic oxygen can be determined during both day and night using two different techniques that both rely on ozone chemistry. The O concentrations retrieved from SABER data are higher by a factor of 2–5 compared to concentrations determined from other measurements and techniques and compiled in current empirical models. This paper presents variability of atomic oxygen with a focus on the diurnal cycle in low latitudes and the seasonal cycle of daily mean atomic oxygen globally. The results show a large diurnal variation, ranging from a factor of 2 to more than a factor of 10, of atomic oxygen near the equator. The relative magnitude varies with season (larger near the equinoxes) and with altitude (largest near 85 km). Vertical transport by the migrating diurnal tide explains the observed variation. The semiannual variation in tidal amplitude affects the seasonal variation of daily average atomic oxygen, which likely indicates that there is irreversible transport by the tides. At high latitudes, the atomic oxygen variation is characterized by wintertime maxima over the altitude range 80–95 km and summertime maxima above. The wintertime peaks are associated with the downwelling from the mean circulation and are particularly strong in late winter of 2004, 2006, and 2009, responding to the unusual dynamical situations in those years.
Indian summer monsoon and winter hydrographic variations over past millennia resolved by clay sedimentation
Authors: Chauhan Onkar S. , Dayal A. M. , Basavaiah Nathani , Kader U. Syed Abdul
Published: September 2010

Reconstruction of century‐scale Indian monsoon and winter hydrography is made from an AMS‐dated core located in the unique region of the southeast Arabian Sea which lies in the pathways of the low‐salinity Bay of Bengal Waters, advecting during winter northeast monsoon (NEM). Based upon clay mineral analyses in seawaters, we identify chlorite and kaolinite as specific clays supplied by the Bay of Bengal Waters and local fluvial flux (by the southwest monsoon (SWM) precipitation from the Peninsular India), respectively, along the southwest continental margin of India. An evaluation of clay flux and δ18O in G. ruber portrays century‐scale weaker SWM precipitation events during ∼450–650 yr, ∼1000 yr, and 1800–2200 cal yr BP. Kaolinite wt % and flux were found to be low during all these events, though chlorite had a persistent or enhanced flux. From the enhanced flux of chlorite and reduced kaolinite/chlorite ratio, during weaker phases of SWM, we deduce a stronger NEM (winter hydrography), implying an inverse coupling between the summer and the winter monsoon.
Tracking aquatic change using chlorin‐specific carbon and nitrogen isotopes: The last glacial‐interglacial transition at Lake Suigetsu, Japan
Authors: Tyler J. , Kashiyama Y. , Ohkouchi N. , Ogawa N. , Yokoyama Y. , Chikaraishi Y. , Staff R. A. , Ikehara M. , Bronk Ramsey C. , Bryant C. , Brock F. , Gotanda K. , Haraguchi T. , Yonenobu H. , Nakagawa T.
Published: September 2010

Joint carbon and nitrogen isotope measurements were made from chlorins (chlorophyll a, phaeophytin a and pyrophaeophytin a) extracted from the last glacial‐interglacial transition sediments of Lake Suigetsu, central Japan. These data highlight both the potential and difficulty of using chlorin‐specific isotopes to track aquatic change from lake sediments. δ13C and δ15N of the three chlorins show coherent patterns with time, supporting the theory that phaeophytin a and pyrophaeophytin a are early diagenetic products of chlorophyll a and that despite this transition, their isotopic signatures remain intact. However, our data suggest that the isotopic composition of phaeophytin a and pyrophaeophytin a can be imprecise proxies for the isotope composition of chlorophyll a, possibly owing to the complex array of factors which affect the synthesis, transformation and sedimentation of these phaeopigments in nature. The total accumulation of organic matter in Lake Suigetsu appears to be controlled by the balance of allocthonous and authocthonous material as reflected by the C/N ratio. However, both bulk organic and chlorin‐specific δ13C show similar changes, suggesting that the first order variability in bulk organic δ13C reflects aquatic change. By contrast, there is no similarity between chlorin and bulk δ15N, suggesting that interpretation of bulk δ15N in this setting is compromised by diagenetic alteration. The isotopic composition of chlorins are interpreted to reflect the response of aquatic primary productivity to post‐glacial environmental change. However, further research into the synthesis and transformation of chlorins in the modern environment is required in order to facilitate a more rigorous approach to interpreting isotope ratios in chlorins extracted from sediments.
Regional downscaling for stable water isotopes: A case study of an atmospheric river event
Authors: Yoshimura Kei , Kanamitsu Masao , Dettinger Michael
Published: September 2010

In this paper an isotope‐incorporated regional model is developed and utilized for simulations of an atmospheric river event that occurred in March 2005. A set of sensitivity experiments and comparisons with observations confirm that the kinetic isotopic exchange between falling droplets and ambient water vapor below the cloud base was mostly responsible for the initial enrichment and subsequent rapid drop of the deuterium abundance in precipitation observed during the event even under humid conditions. According to the budget analysis the increase in isotopic composition during the latter half of the event was primarily due to horizontal advection. The contribution of condensation from different atmospheric heights to the ground precipitation was not reflected in the precipitation isotopes.
Negative BOLD-fMRI Signals in Large Cerebral Veins
Authors: Bianciardi Marta , Fukunaga Masaki , van Gelderen Peter , de Zwart Jacco A , Duyn Jeff H
Published: September 2010

Reductions in blood oxygenation level dependent (BOLD)-functional magnetic resonance imaging (fMRI) signals below baseline levels have been observed under several conditions as negative activation in task-activation studies or anticorrelation in resting-state experiments. Converging evidence suggests that negative BOLD signals (NBSs) can generally be explained by local reductions in neural activity. Here, we report on NBSs that accompany hemodynamic changes in regions devoid of neural tissue. The NBSs were investigated with high-resolution studies of the visual cortex (VC) at 7T. Task-activation studies were performed to localize a task-positive area in the VC. During rest, robust negative correlation with the task-positive region was observed in focal regions near the ventricles and dispersed throughout the VC. Both positive and NBSs were dependent on behavioral condition. Comparison with high-resolution structural images showed that negatively correlated regions overlapped with larger pial and ependymal veins near sulcal and ventricular cerebrospinal fluid (CSF). Results from multiecho fMRI showed that NBSs were consistent with increases in local blood volume. These findings confirm theoretical predictions that tie neural activity to blood volume increases, which tend to counteract positive fMRI signal changes associated with increased blood oxygenation. This effect may be more salient in high-resolution studies, in which positive and NBS may be more often spatially distinct.
Nadph Oxidase Mediates Striatal Neuronal Injury after Transient Global Cerebral Ischemia
Authors: Yoshioka Hideyuki , Niizuma Kuniyasu , Katsu Masataka , Okami Nobuya , Sakata Hiroyuki , Kim Gab Seok , Narasimhan Purnima , Chan Pak H
Published: September 2010

Medium spiny neurons (MSNs) constitute most of the striatal neurons and are known to be vulnerable to ischemia; however, the mechanisms of the vulnerability remain unclear. Activated forms of nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase (NOX), which require interaction between cytosolic and membrane-bound subunits, are among the major sources of superoxide in the central nervous system. Although increasing evidence suggests that NOX has important roles in neurodegenerative diseases, its roles in MSN injury after transient global cerebral ischemia (tGCI) have not been elucidated. To clarify this issue, C57BL/6 mice were subjected to tGCI by bilateral common carotid artery occlusion for 22 minutes. Western blot analysis revealed upregulation of NOX subunits and recruitment of cytosolic subunits to the cell membrane at early (3 to 6 hours) and late (72 hours) phases after tGCI. Taken together with immunofluorescent studies, this activation arose in MSNs and endothelial cells at the early phase, and in reactive microglia at the late phase. Pharmacological and genetic inhibition of NOX attenuated oxidative injury, microglial activation, and MSN death after tGCI. These findings suggest that NOX has pivotal roles in MSN injury after tGCI and could be a therapeutic target for brain ischemia.
Infrared birefringence imaging of residual stress and bulk defects in multicrystalline silicon
Authors: Ganapati Vidya , Schoenfelder Stephan , Castellanos Sergio , Oener Sebastian , Koepge Ringo , Sampson Aaron , Marcus Matthew A. , Lai Barry , Morhenn Humphrey , Hahn Giso , Bagdahn Joerg , Buonassisi Tonio
Published: September 2010

This manuscript concerns the application of infrared birefringence imaging (IBI) to quantify macroscopic and microscopic internal stresses in multicrystalline silicon (mc-Si) solar cell materials. We review progress to date, and advance four closely related topics. (1) We present a method to decouple macroscopic thermally-induced residual stresses and microscopic bulk defect related stresses. In contrast to previous reports, thermally-induced residual stresses in wafer-sized samples are generally found to be less than 5 MPa, while defect-related stresses can be several times larger. (2) We describe the unique IR birefringence signatures, including stress magnitudes and directions, of common microdefects in mc-Si solar cell materials including: β-SiC and β-Si3N4 microdefects, twin bands, nontwin grain boundaries, and dislocation bands. In certain defects, local stresses up to 40 MPa can be present. (3) We relate observed stresses to other topics of interest in solar cell manufacturing, including transition metal precipitation, wafer mechanical strength, and minority carrier lifetime. (4) We discuss the potential of IBI as a quality-control technique in industrial solar cell manufacturing.
Characterization of hydrogen-induced crack initiation in metastable austenitic stainless steels during deformation
Authors: Zhang L. , An B. , Fukuyama S. , Iijima T. , Yokogawa K.
Published: September 2010

Hydrogen-induced crack initiation in hydrogen-charged metastable austenitic stainless steels during deformation at 295 K is characterized by performing a combined tensile and hydrogen release experiment and scanning probe microscopy. Strain-induced martensite (α′) not only provides a path for rapid hydrogen diffusion in austenite (γ) but also promotes crack initiation. Hydrogen rapidly diffuses from α′ and accumulates at the boundary between the α′-rich and γ-rich zones during deformation due to the high hydrogen diffusivity and low hydrogen solubility in α′, resulting in crack initiation at the boundary between the α′-rich and γ-rich zones. The hydrogen-induced crack initially grows along the boundary between the α′-rich and γ-rich zones and then propagates in the α′-rich zone.
Transition-density-fragment interaction approach for exciton-coupled circular dichroism spectra
Authors: Fujimoto Kazuhiro J.
Published: September 2010

A transition-density-fragment interaction (TDFI) method for exciton-coupled circular dichroism (ECCD) spectra is proposed. The TDFI method was previously developed for excitation-energy transfer, which led to the successful estimation of the electronic coupling energy between donor and accepter molecules in xanthorhodopsin [K. J. Fujimoto and S. Hayashi, J. Am. Chem. Soc. 131, 14152 (2009)]. In the present study, the TDFI scheme is extended to the ECCD spectral calculation based on the matrix method and is applied to a dimerized retinal (all-trans N-retinylidene-L-alanine Schiff base) chromophore. Compared with the dipole-dipole and transition charge from ESP methods, TDFI has a much improved description of the electronic coupling. In addition, the matrix method combined with TDFI can reduce the computational costs compared with the full quantum-mechanical calculation. These advantages of the present method make it possible to accurately evaluate the CD Cotton effects observed in experiment.
Chemical ionization tandem mass spectrometer for the in situ measurement of methyl hydrogen peroxide
Authors: St. Clair Jason M. , McCabe David C. , Crounse John D. , Steiner Urs , Wennberg Paul O.
Published: September 2010

A new approach for measuring gas-phase methyl hydrogen peroxide [(MHP) CH3OOH] utilizing chemical ionization mass spectrometry is presented. Tandem mass spectrometry is used to avoid mass interferences that hindered previous attempts to measure atmospheric CH3OOH with CF3O− clustering chemistry. CH3OOH has been successfully measured in situ using this technique during both airborne and ground-based campaigns. The accuracy and precision for the MHP measurement are a function of water vapor mixing ratio. Typical precision at 500 pptv MHP and 100 ppmv H2O is ±80 pptv (2 sigma) for a 1 s integration period. The accuracy at 100 ppmv H2O is estimated to be better than ±40%. Chemical ionization tandem mass spectrometry shows considerable promise for the determination of in situ atmospheric trace gas mixing ratios where isobaric compounds or mass interferences impede accurate measurements.
High-resolution electron momentum spectroscopy of valence satellites of carbon disulfide
Authors: Huang Chengwu , Shan Xu , Zhang Zhe , Wang Enliang , Li Zhongjun , Chen XiangJun
Published: September 2010

The binding energy spectrum of carbon disulphide (CS2) in the energy range of 9–23 eV has been measured by a high-resolution (e,2e) spectrometer employing asymmetric noncoplanar kinematics at an impact energy of 2500 eV plus the binding energy. Taking the advantage of the high energy resolution of 0.54 eV, four main peaks and five satellites in the outer-valence region are resolved. The assignments and pole strengths for these satellite states are achieved by comparing the experimental electron momentum profiles with the corresponding theoretical ones calculated using Hartree–Fock and density functional theory methods. The results are also compared in detail with the recent SAC-CI general-R calculations. General agreement is satisfactory, while the present experiment suggests cooperative contributions from Π2u, Σg+2 states to satellite 2 and Σg+2, Π2g states to satellite 3. Besides, relatively low pole strength for X Π2g state is obtained which contradicts all the theoretical calculations [2ph-TDA, ADC(3), SAC-CI general-R, ADC(4)] so far.
Imaging the nature of the mode-specific chemistry in the reaction of Cl atom with antisymmetric stretch-excited CH4
Authors: Kawamata Hiroshi , Liu Kopin
Published: September 2010

Following up our preliminary communication [Kawamata et al., Phys. Chem. Chem. Phys. 10, 4378 (2008)], the effects of the antisymmetric-stretching excitation of methane on the Cl(P23/2)+CH4 reaction are examined here over a wide range of initial collision energy in a crossed molecular beam imaging experiment. The antisymmetric stretch of CH4 is prepared in a single rovibrational state of (v3=1, j=2) by direct infrared absorption, and the major product states of CH3(v=0) are probed by a time-sliced velocity-map imaging method. We find that at fixed collision energies, the stretching excitation promotes reaction rate. Compared to the ground-state reaction, this vibrational enhancement factor is, however, no more effective than the translational enhancement. The correlated HCl(v′=1) vibrational branching fraction shows a striking dependence on collision energies, varying from 0.7 at Ec=2 kcal mol−1 to about 0.2 at 13 kcal mol−1. This behavior resembles the previously studied Cl+CH2D2(v6=1), but is in sharp contrast to the Cl+CHD3(v1=1) and CH2D2(v1=1) reactions. Dependences of experimental results on the probed rotational states of CH3(v=0) are also elucidated. We qualitatively interpret those experimental observations based on a conceptual framework proposed recently.
Enhanced exciton photoluminescence in the selectively Si-doped GaAs/AlxGa1−xAs heterostructures
Authors: Kundrotas J. , Čerškus A. , Nargelienė V. , Sužiedėlis A. , Ašmontas S. , Gradauskas J. , Johannessen A. , Johannessen E. , Umansky V.
Published: September 2010

Experimental results examining the photoluminescence spectra of selectively Si-doped GaAs/AlxGa1−xAs heterostructures is presented. Possible mechanisms of carrier recombination are discussed with a special emphasis on the peculiarities of excitonic photoluminescence. Strong intensity lines in photoluminescence spectra are associated with the formation and enhancement of free exciton and exciton-polariton emission in the flat band region of an active i-GaAs layer. The excitonic PL intensity is sensitive to the excitation intensity indicating high nonlinear behavior of spectral-integrated photoluminescence intensity and exciton line narrowing. These observed phenomena may be related to the collective interaction of excitons and the interaction of excitons with emitted electromagnetic waves. The gain of the amplification of the excitonic photoluminescence intensity in the heterostructure was found to be more than 1000 times larger than the intensity of i-GaAs active layer. The quality factor of the exciton line emission and the exciton-polariton line was found to be 3800 and 7600, respectively.
Probing defects in chemically synthesized ZnO nanostrucures by positron annihilation and photoluminescence spectroscopy
Authors: Chaudhuri S. K. , Ghosh Manoranjan , Das D. , Raychaudhuri A. K.
Published: September 2010

The present article describes the size induced changes in the structural arrangement of intrinsic defects present in chemically synthesized ZnO nanoparticles of various sizes. Routine x-ray diffraction and transmission electron microscopy have been performed to determine the shapes and sizes of the nanocrystalline ZnO samples. Detailed studies using positron annihilation spectroscopy reveals the presence of zinc vacancy. Whereas analysis of photoluminescence results predict the signature of charged oxygen vacancies. The size induced changes in positron parameters as well as the photoluminescence properties, has shown contrasting or nonmonotonous trends as size varies from 4 to 85 nm. Small spherical particles below a critical size (∼23 nm) receive more positive surface charge due to the higher occupancy of the doubly charge oxygen vacancy as compared to the bigger nanostructures where singly charged oxygen vacancy predominates. This electronic alteration has been seen to trigger yet another interesting phenomenon, described as positron confinement inside nanoparticles. Finally, based on all the results, a model of the structural arrangement of the intrinsic defects in the present samples has been reconciled.
Precise and millidegree stable temperature control for fluorescence imaging: Application to phase transitions in lipid membranes
Authors: Farkas Elaine R. , Webb Watt W.
Published: September 2010

We present the design of a custom temperature-controlled chamber suitable for water or oil immersion fluorescence microscopy and its application to phase behavior in lipid bilayer vesicles. The apparatus is self-contained and portable, suitable for multiuser microscopy facilities. It offers a higher temperature resolution and stability than any comparable commercial apparatus, on the order of millidegrees. We demonstrate the utility of the system in the study of miscibility transitions in model membranes. The temperature-dependent phase behavior of model membrane systems that display liquid-ordered (Lo) phase coexistence with the liquid-disordered (Ld) phase is relevant to understanding the existence of heterogeneities in biological cell plasma membranes, ubiquitously termed “lipid rafts.”
Stress state of diamond and gold under nonhydrostatic compression to 360 GPa
Authors: Wang Jianghua , He Duanwei , Duffy Thomas S.
Published: September 2010

Diamond and gold powders were compressed nonhydrostatically in a diamond anvil cell and examined by x-ray diffraction using a radial geometry to evaluate the evolution of stresses and strains in these materials to ultrahigh pressure. We found that near isostrain continuity developed across diamond and gold grains under uniaxial compression. The observed mean pressure of diamond powder reached to 360(40) GPa while it was only 31(1) GPa for the polycrystalline gold under the highest load. Polycrystalline diamond can support a microscopic deviatoric stress of 160(18) GPa at about 360 GPa. Due to the deformation of the diamond anvil culet, the macroscopic differential stress of the diamond sample was limited to about 43(8) GPa. There is no evidence that the diamond grains have yielded in our experimental pressure range.
Embedded Ag-rich nanodots in PbTe: Enhancement of thermoelectric properties through energy filtering of the carriers
Authors: Paul Biplab , V Ajay Kumar , Banerji P.
Published: September 2010

The concept of energy filtering of the carriers to control the thermoelectric properties of PbTe is experimentally applied in this present work. The energy barriers at the grain interfaces of the nanocomposites and the embedded Ag-rich nanodots within the grains are supposed to control the energy dependency of carrier scattering: that is what we mean by energy filtering of carriers. As a case study, vertical Bridgman grown bulk PbTe:undoped, PbTe:Ag crystals and nanocomposites of PbTe:Ag are used as samples. Thermoelectric properties of all the samples have been evaluated through temperature dependent electrical conductivity, Seebeck coefficient and room temperature Hall and thermal conductivity measurements. It is found that the PbTe:Ag nanocomposites has the highest power factor of 18.78×10−4 W m−1 K−2 with a room temperature thermal conductivity of 1.69 W m−1 K−1. The crystal structures of these samples show the effective potential barrier at the grain boundaries and embedded nanodots within the grains to facilitate the energy filtering of the carriers.
CdS/CdTe solar cells with MoOx as back contact buffers
Authors: Lin Hao , Xia Wei , Wu Hsiang N. , Tang Ching W.
Published: September 2010

Ohmic back contacts for CdS/CdTe solar cells with MoOx as the contact buffer have been demonstrated. With contacts such as MoOx/Ni and MoOx/Al, cell efficiencies comparable to those with conventional back contacts have been produced. Thermal stress tests indicate that MoOx is effective in suppressing metal diffusion into p-CdTe. The usefulness of MoOx is attributed to its unusually high work function which is needed to match that of p-type CdTe in producing contacts of low resistance.
Observation of coherent phonons in metallic carbon nanotubes
Authors: Kato Keiko , Oguri Katsuya , Ishizawa Atsushi , Gotoh Hideki , Nakano Hidetoshi , Sogawa Tetsuomi
Published: September 2010

We investigated the ultrafast dynamics of coherent phonons with sub-10 fs laser pulses in metallic single-walled carbon nanotubes (m-SWCNTs). We identified radial breathing mode (RBM), D-mode, and G-mode coherent phonons in m-SWCNTs. We also resolved G−- and G+-mode coherent phonons, which correspond to the longitudinal and transverse optical phonon modes, respectively. The frequencies of the RBM coherent phonons shift with increases in laser intensity, suggesting that photocarriers modify the phonon frequency.
The transition in hydrogen sensing behavior in noncontinuous palladium films
Authors: Kiefer Thomas , Villanueva Luis Guillermo , Fargier Frédéric , Favier Frédéric , Brugger Jürgen
Published: September 2010

The morphological transition in ultrathin palladium (Pd) films around the percolation threshold and the related transition in hydrogen sensing behavior is investigated. We find that besides the transition from continuous to discontinuous Pd, an intermediate - semicontinuous-state must be considered. It shows hydrogen sensing features of both continuous and discontinuous film types, simultaneously. This study focuses on the discontinuous-semicontinuous transition. Experimental evidence is supported by studying the evolution of the electrical resistance with temperature, under hydrogen exposure and after thermal annealing. The results are highly relevant for the optimization of nanogap based hydrogen sensors.
The nature of high voltage initiation of an electrical arc in a vacuum
Authors: Beilis I. I.
Published: September 2010

Generally the gap voltage at the moment of arc initiation in a vacuum is significantly larger than the voltage in developed arcs. This phenomenon was studied here suggesting a physical model for initially triggered at the bulk cathode plasma and then for appeared transient spot. The model allows calculating the transient energy flux to the cathode and the transient cathode potential drop (CPD). It was shown that the CPD at the moment of spot ignition is relatively large and significantly contributes to the arc voltage at arc ignition. The subsequent voltage decrease can be understood from the transient CPD behavior during arc development. The voltage oscillation in an arc was explained by suggested model taking into account the spot shifting on a cold location.
Low-frequency noise in amorphous indium-gallium-zinc oxide thin-film transistors from subthreshold to saturation
Authors: Park Jae Chul , Kim Sang Wook , Kim Chang Jung , Kim Sungchul , Kim Dae Hwan , Cho In-Tak , Kwon Hyuck-In
Published: September 2010

We investigate the low-frequency noise (LFN) behaviors of amorphous indium-gallium-zinc oxide thin-film transistors in the subthreshold, Ohmic, and saturation regimes. Measured LFNs are proportional to 1/fγ, with γ=0.8–0.9 in all operation regimes. It is found that the LFN behavior follows the carrier number fluctuation model in the subthreshold regime, whereas in the Ohmic and saturation regimes, it agrees well with the bulk mobility fluctuation model. We also observe that the origin of 1/f noise in the Ohmic regime changes from the bulk mobility fluctuation to the carrier number fluctuation as the channel length decreases.
Selective area growth of high quality InP on Si (001) substrates
Authors: Wang G. , Leys M. R. , Loo R. , Richard O. , Bender H. , Waldron N. , Brammertz G. , Dekoster J. , Wang W. , Seefeldt M. , Caymax M. , Heyns M. M.
Published: September 2010

In this work, we demonstrate the selective area growth of high quality InP layers in submicron trenches on exactly (001) oriented Si substrates by using a thin Ge buffer layer. Antiphase domain boundaries were avoided by annealing at the Ge surface roughening temperature to create additional atomic steps on the Ge buffer layer. The mechanism of Ge surface atomic step formation and the corresponding step density control method are illustrated. The elimination of antiphase boundaries from the optimized Ge buffer layer, together with the defect necking effect, yield defect-free top InP layers inside the trenches.
Long-period fiber gratings spontaneously written by a mechanism markedly different from Hill grating formation
Authors: Tu H. , Shin S. , John R. , Boppart S. A.
Published: September 2010

Pumping a nonlinear germanosilicate fiber with intense near-infrared femtosecond laser pulses for supercontinuum generation may invoke multiphoton-assisted photosensitivity of glasses to write a long-period fiber grating. In sharp contrast to the spontaneous formation of a Hill grating that resonates with the writing wavelength through first-order diffraction, the long-period fiber grating resonates with the writing wavelength through second-order diffraction. This finding highlights the surprising light-matter interaction in a waveguide.
Carbon nanotube-induced chirality in an achiral liquid crystal
Authors: Basu Rajratan , Boccuzzi Krysta A. , Ferjani Sameh , Rosenblatt Charles
Published: September 2010

A small quantity of carbon nanotubes was dispersed in an achiral liquid crystal (LC), and the mixture was found to exhibit a weak degree of chirality. The induced chirality in the LC was probed by means of the electroclinic effect in the LC’s smectic-A phase, which showed significant pretransitional behavior on approaching the smectic-A–smectic-C transition temperature from above. The results suggest that there is a net chirality associated with the carbon nanotubes, which is transmitted into the LC.
Lateral diffusion of minority carriers in InAsSb-based nBn detectors
Authors: Plis Elena , Myers S. , Kutty M. N. , Mailfert J. , Smith E. P. , Johnson S. , Krishna S.
Published: September 2010

We report on the investigation of lateral diffusion of minority carriers in InAsSb based photodetectors with the nBn design. Diffusion lengths (DLs) were extracted from temperature dependent I-V measurements. The behavior of DL as a function of applied bias, temperature, and composition of the barrier layer was investigated. The obtained results suggest that lateral diffusion of minority carriers is not the limiting factor for InAsSb based nBn mid-wave infrared detector performance at high temperatures (>200 K). The detector with an As mole fraction of 10% in the barrier layer has demonstrated values of DL as low as 7 μm (Vb=0.05 V) at 240 K.
Structural and optical properties of GaInP grown on germanium by metal-organic chemical vapor deposition
Authors: He W. , Lu S. L. , Dong J. R. , Zhao Y. M. , Ren X. Y. , Xiong K. L. , Li B. , Yang H. , Zhu H. M. , Chen X. Y. , Kong X.
Published: September 2010

Structural and optical properties of Si-doped as well as nominally undoped GaInP epilayers grown on Germanium substrates by metal-organic chemical vapor deposition have been investigated by high resolution transmission electron microscope and photoluminescence (PL). Si incorporation results in an increased inner band PL transition and a blue shift of PL energy with increasing temperature, which arises from the trapping states around Ge-GaInP interface due to Ge diffusion to GaInP epilayer as well as Si doping. For the inter band PL transition, a competition between the emission processes near the band edge and in the ordered GaInP domains is responsible for the inverted S shape temperature dependence of PL peaks. By analyzing the time-resolved PL results, we attribute this emission near the ordered states to the localized states due to the potential fluctuation, which is induced by the compositional inhomogeneity of Ga and In in the partially ordered GaInP.
Positive and negative effects of phoretic mites on the reproductive output of an invasive bark beetle
Authors: Hodgkin Lisa K. , Elgar Mark A. , Symonds Matthew R. E.
Published: September 2010

When multiple species coexist upon a single host, their combined effect on the host can be unpredictable. We explored the effect of phoretic mites on the reproductive output of the five-spined bark beetle, Ips grandicollis. Using correlative approaches and experimental manipulation of mite numbers we examined how mite load affected the number, size and condition of bark beetle offspring produced. We found that mites have both negative and positive consequences on different aspects of bark beetle reproduction. Females from which mites were removed were more fecund and produced larger offspring than females with mites, implying a cost of mite loads. However, when mites were present on females, those bearing the highest mite loads produced offspring that were larger and in better condition, indicating a beneficial effect of mites. These data suggest that phoretic interactions between mites and bark beetles differ over the course of the host’s lifespan, with either the mites interacting in different ways with different life stages of the host (parasitic on adult, mutualistic with larvae), and/or the beetles being host to different mite assemblages over their lifetime.
Sandplay analysis: research in progress
Authors: Aite Paolo
Published: September 2010

Inspired by Jung's distinction between ‘active’ and ‘passive’ fantasy, sandplay is proposed as a means to stimulate an ‘active fantasy’ in analysis. During child development, the act of playing, with its tangible and bodily nature, triggers an attitude of consciousness toward the perception of unconscious contents. Sandplay works in a similar way with adults. The processes of symbolisation and expressivity take form in a ‘thinking in images’, a relation established between concrete perceptions stimulated by the material of sandplay and emotions and affects just perceived, but not easily expressed in ordinary words. The technique of sandplay in the analytic session is described and illustrated through a clinical vignette.
Psychoanalysis and analytical psychology: a paradoxical relationship
Authors: Trevi Mario
Published: September 2010

Psychoanalysis and analytical psychology have a paradoxical relationship which suggests their complementarity. First, the hypothesis that Jung's first aspiration was to create a vast and inclusive psychology able to comprehend psychoanalysis as a specific case is made and explored through Jungian typological theory and complex theory. Then, under the feature of opposition, it is argued that analytical psychology developed a new idea of the relationship of the individual in relation to the culture as a complex process co-determining the imaginal life of the individual together with his personal infant vicissitudes. Thus, a complex and paradoxical image describes the relationship between analytical psychology and psychoanalysis, where each of them represents a containing horizon for the other and at the same time a germinal nucleus that is contained in each by the other.
Analytical psychology and psychiatry in Italy today
Authors: Malinconico Angelo
Published: September 2010

The aim of this article is to offer some reflections on the potential of analytical psychology in the field of psychiatric cure of psychotic patients mostly in the context of public mental health services. It will do so by drawing on Italian past and present experiences, as well as investigating future perspectives. The Italian mental health legislation which has been in force for 32 years now is still of particular value and shows how the clinical, political, economic and hermeneutic realms are interconnected and worthy of attention especially in the therapy of psychosis. Analytical psychology can and must set itself up as the organiser of meaning between the different fields of psychiatry, depth psychology and socio-psychiatry. Analysed in his social and political context, the therapy of the psychotic patient makes of individuation a political as well as a therapeutic act of searching for the Self of both individuals and systems. This would signal the return of analytical psychology to its roots in psychiatry from which it rose up and from which it split off as a result of grave inadequacies on both sides.
The profits of free books: an experiment to measure the impact of open access publishing
Authors: SNIJDER Ronald
Published: September 2010

This article describes an experiment to measure the impact of open access (OA) publishing of academic books. During a period of nine months, three sets of 100 books were disseminated through an institutional repository, the Google Book Search program, or both channels. A fourth set of 100 books was used as control group. OA publishing enhances discovery and online consultation. Within the context of the experiment, no relation could be found between OA publishing and citation rates. Contrary to expectations, OA publishing does not stimulate or diminish sales figures. The Google Book Search program is superior to the repository.
Optical emission spectroscopy in low-temperature plasmas containing argon and nitrogen: determination of the electron temperature and density by the line-ratio method
Authors: Zhu Xi-Ming , Pu Yi-Kang
Published: September 2010

This article reviews a variety of methods to obtain the electron temperature and density by the emission line ratios for low-temperature plasmas containing argon or nitrogen gas. Based on the collisional–radiative model of excited particles, the underlying principle of each of these methods is described, along with the criterion on how to select an appropriate line-ratio method according to the discharge conditions. Limitations on the application of each line-ratio technique are also discussed.
Quantification of the aggregation of magnetic nanoparticles with different polymeric coatings in cell culture medium
Authors: Eberbeck D , Kettering M , Bergemann C , Zirpel P , Hilger I , Trahms L
Published: September 2010

The knowledge of the physico-chemical characteristics of magnetic nanoparticles (MNPs) is essential to enhance the efficacy of MNP-based therapeutic treatments (e.g. magnetic heating, magnetic drug targeting). According to the literature, the MNP uptake by cells may depend on the coating of MNPs, the surrounding medium as well as on the aggregation behaviour of the MNPs. Therefore, in this study, the aggregation behaviour of MNPs in various media was investigated. MNPs with different coatings were suspended in cell culture medium (CCM) containing fetal calf serum (FCS) and the distribution of the hydrodynamic sizes was measured by magnetorelaxometry (MRX). FCS as well as bovine serum albumin (BSA) buffer (phosphate buffered saline with 0.1% bovine serum albumin) may induce MNP aggregation. Its strength depends crucially on the type of coating. The degree of aggregation in CCM depends on its FCS content showing a clear, local maximum at FCS concentrations, where the IgG concentration (part of FCS) is of the order of the MNP number concentration. Thus, we attribute the observed aggregation behaviour to the mechanism of agglutination of MNPs by serum compartments as for example IgG. No aggregation was induced for MNPs coated with dextran, polyarabic acid or sodium phosphate, respectively, which were colloidally stable in CCM.
Behaviour of group IIIA impurities in PbTe: implications to improve thermoelectric efficiency
Authors: Xiong K , Lee G , Gupta R P , Wang W , Gnade B E , Cho Kyeongjae
Published: September 2010

We investigated the impact of doping group IIIA elements (Al, Ga, In and Tl) on the electronic structure and stability of PbTe by first principles calculations. The impurity-induced defect level changes as a function of the charge state of the impurity. We find that Al and In prefer to act as donors while Ga and Tl tend to act as acceptors in PbTe. Our analysis supports the ‘impurity level’ model where an impurity-induced localized state overlaps either the conduction band or valence band of PbTe, but our results do not agree with ‘mix-valence’ (i.e. 2In2+ → In+ + In3+) or ‘auto-compensation’ (i.e. 2In0 → In+ + In−) models. Our calculations suggest that Tl and In are suitable dopants for improving the thermoelectric efficiency through enhancing the Seebeck coefficient for p- and n-type PbTe, respectively.