bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective mass of InN estimated by Raman scattering
Authors: Kim Jung Gon , Kamei Yasuhito , Hasuike Noriyuki , Harima Hiroshi , Kisoda Kenji , Sasamoto Kouhei , Yamamoto Akio
Published: May 2010

We have estimated the longitudinal effective mass (m‖) of electron in n‐type InN films by Raman scattering. The samples were grown by MOVPE (metal organic vapor phase epitaxy) with free carrier concentration of n =6.7×1018‐9.9×1018 cm‐3 according to Hall measurement. A weak Raman signal observed at ∼430 cm‐1 at room temperature was sharpened and shifted to higher frequency toward the A1(TO)‐phonon mode at 447 cm‐1 with increasing n. This mode was assigned to the lower branch (L‐) of the longitudinal‐optic‐phonon‐plasmon‐coupled (LOPC) mode. The line shape was carefully analyzed by a semi‐classical line‐shape fitting analysis assuming deformation potential and electro‐optic coupling mechanisms for the light scattering process. A line‐shape fitting analysis was conducted by adjusting three major parameters; electron density, effective mass and plasmon damping rate. The analysis well reproduced values of electron density and mobility deduced by Hall measurement. Electron effective mass of m‖*/m0 = 0.05 (±0.01) was also obtained as the best‐fit parameter. The result agrees well with previous data obtained by other optical methods. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hall mobilities in GaNxAs1‐x
Authors: Olea Javier , Yu Kin Man , Walukiewicz Wladek , Gonzalez‐Díaz Germán
Published: May 2010

In this work we report a systematic study of the electron and hole mobilities of GaNxAs1‐x alloys with different dopants (Zn, Te) and carrier concentrations (1017‐1019 cm‐3). We found a very slight reduction of the hole mobility in p‐GaNxAs1‐x compared to p‐GaAs, indicating that for small N contents (∼1.6%) the valence band is not affected by the N incorporation. In a striking contrast, incorporation of even small amounts of N leads to an abrupt reduction of the electron mobility in n‐GaNxAs1‐x. We further show that the processes that limit the mobility in GaNxAs1‐x can be explained by the band broadening and the random field scatterings. Considering these two scattering mechanisms we calculated the dependence of electron mobilities on electron concentration as well as on N composition in GaNxAs1‐x. The calculations agree reasonably well with experiment data of maximum electron mobilities with alloy composition. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Boltzmann–Hamel equations for the optimal control of mechanical systems with nonholonomic constraints
Authors: Maruskin Jared M. , Bloch Anthony M.
Published: May 2010

In this paper, we generalize the Boltzmann–Hamel equations for nonholonomic mechanics to a form suited for the kinematic or dynamic optimal control of mechanical systems subject to nonholonomic constraints. In solving these equations one is able to eliminate the controls and compute the optimal trajectory from a set of coupled first‐order differential equations with boundary values. By using an appropriate choice of quasi‐velocities, one is able to reduce the required number of differential equations bymand 3mfor the kinematic and dynamic optimal control problems, respectively, wheremis the number of nonholonomic constraints. In particular we derive a set of differential equations that yields the optimal reorientation path of a free rigid body. In the special case of a sphere, we show that the optimal trajectory coincides with the cubic splines onSO(3). Copyright © 2010 John Wiley & Sons, Ltd.
Estimating channel‐forming discharge in urban watercourses
Authors: Annable W. K. , Lounder V. G. , Watson C. C.
Published: May 2010

Several methods of estimating channel‐forming discharge were conducted on 12 quasi‐stable urban stream channels ranging from 9 to 99% urban land use to test their applicability in the urban condition. Bankfull stage was identified at a series of locations along each study reach and it was found that the most consistent observations of bankfull discharge occurred during flood conditions where bankfull stage was identified at the top of point bars along the convex arc of bends. The largest errors in estimation occurred at gauge stations where cross‐sectional geometry had been altered to conform to bridges or culverts rather than the channel morphology. Independent evaluations of channel forming discharge were conducted by 11 practitioners ranging from 10 years to 43 years of experience with similar findings and errors.

Various methods of relating frequency return periods were evaluated using annual peak series discharge observations and continuous 15‐min systematic discharge records using partial duration series analysis. Bankfull discharge was observed to occur more than once a year in all of the urban streams studied and often averaged from 4 to 8 bankfull discharge or larger events per year. In one particular case in a single given year 18 events exceeding bankfull discharge were observed. No specific correlations were identified between frequency return periods and land use change. However, based upon the findings of this study, the applicability of employing annual series peak discharge data to evaluate bankfull frequency return in urban stream channels is highly discouraged. Copyright © 2010 John Wiley & Sons, Ltd.
ToF‐SIMS and principal component analysis: Effect of film thickness on crystal surfaces of polymers
Authors: Lau Yiu‐Ting R. , Weng Lu‐Tao , Ng Kai‐Mo , Chan Chi‐Ming
Published: May 2010

The effect of film thickness on the structural conformation of the surfaces of the amorphous state, edge‐on lamellae and flat‐on lamellae of a semiflexible polymer, poly(bisphenol‐A‐etheroctane), was investigated by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) with the aid of principal component analysis (PCA). PCA results empirically indicate that a structurally regular polymer surface was obtained with the formation of the flat‐on lamellae from the amorphous state at a low degree of supercooling. A higher concentration of end group and cilium ion fragments, which are indicative of free chain ends, was observed on the edge‐on lamellar surfaces than on the amorphous and the flat‐on lamellar surfaces. This finding was attributed to the fact that the lateral surface of the edge‐on lamellae contains many growth fronts, leaving behind a large number of uncrystallized chain remnants on the surfaces. Structural disorder was facilitated on both edge‐on and flat‐on lamellar surfaces as the film thickness decreased. Hence, this PCA study offers new insights into the nonequilibrium nature of polymer crystals and the mechanism of polymer crystallization in thin and ultrathin films. Copyright © 2010 John Wiley & Sons, Ltd.
Femto‐ and attosecond electron dynamics in 5′‐Guanosine monophosphate interface as probed by resonant Auger spectroscopy
Authors: Ikeura‐Sekiguchi Hiromi , Sekiguchi Tetsuhiro
Published: May 2010

To help in our understanding of the electron transport properties of deoxyribonucleic acid (DNA), it is useful to study the interfacial interaction between each nucleotide building block of DNA. Electron transfer properties between phosphate groups in microcrystalline 5′‐Guanosin monophosphate (GMP) were probed using energy‐dependent resonant Auger spectroscopy. Results show that the phosphate group of GMP forms an extended state along the phosphate directions similar to the case of DNA phosphate backbones. Electron delocalization time of the phosphate groups in GMP is faster than those of DNA, as estimated using the core‐hole clock method. This suggests that interface between GMP phosphate groups would have the lowest tunneling barrier among DNA related systems. Although the π–π coupling of nucleobases is only recognized as charge‐transfer pathway in DNA and related systems, another conduction pathway through phosphate groups would be possible. Copyright © 2010 John Wiley & Sons, Ltd.
Influence of the ferroelectric polarization on the electronic structure of BaTiO3 thin films
Authors: Barrett N. , Rault J. , Krug I. , Vilquin B. , Niu G. , Gautier B. , Albertini D. , Lecoeur P. , Renault O.
Published: May 2010

Micron scale ferroelectric (FE) domains have been written into a 20‐nm‐thick epitaxial thin film of BaTiO3 (001) [BTO(001)] on a Nb‐doped SrTiO3 substrate using a piezoforce microscope (PFM). The domain‐dependent electronic structure has been studied using fully energy‐filtered photoemission electron microscopy (PEEM) and synchrotron radiation. Shifts, induced by FE polarization, of up to 300 meV were observed in the work function of the sample. The surface is Ba‐O terminated. Polarization‐induced distortion of the electronic structure was observed in the valence band and on the Ba 3d, Ti 2p and O 1s core levels of BTO. Polarization‐dependent surface adsorption was observed. A simple electrostatic model based on net surface charge is not sufficient to explain the observed modifications in the electronic levels. Copyright © 2010 John Wiley & Sons, Ltd.
Developing ToF‐SIMS methods for investigating the degradation of plastic debris on beaches
Authors: Biesinger Mark C. , Corcoran Patricia L. , Walzak Mary Jane
Published: May 2010

Plastic debris in the Earth's oceans and larger freshwater (FW) bodies presents a serious environmental threat to aquatic organisms. Degradation of plastic by mechanical erosion and chemical weathering is minimal in water. Once deposited on beaches, plastic fragments are exposed to UV radiation and physical processes controlled by winds, currents and waves. Recent work1 has indicated that saltwater (SW) beach plastics feature both mechanically and chemically weathered surface textures, wherein mechanically weakened fractures are the sites of granular oxidation textures. Analysis of lacustrine (FW) beach plastics is now ongoing, and shows similar textural effects of mechanical and chemical weathering.

TOF‐SIMS, with its high spatial resolution and ability to detect molecular species, is ideally suited to explore chemical changes and oxidative processes occurring in these plastics. The method enables detection of low levels of absorbed species present in oxidized polymeric materials.2 TOF‐SIMS analysis is currently being conducted to investigate the oxidation process in polyethylene beach plastics from both SW (Kauai, HI, USA) and FW (Lake Huron, ON, Canada) beaches. Copyright © 2010 John Wiley & Sons, Ltd.
Development of chain‐folding of semicrystalline polymers in thin films: a combined ToF‐SIMS and PCA analysis
Authors: Lau Yiu‐Ting R. , Weng Lu‐Tao , Ng Kai‐Mo , Chan Chi‐Ming
Published: May 2010

Poly(bisphenol‐A‐etheralkane), BA‐Cn(n, which is the number of aliphatic CH2 units, = 8 and 10), composed of rigid and flexible segments, is a semicrystalline polymer. In 50‐nm‐thick films, the polymers tend to develop flat‐on lamellae at the surfaces. Principal component analyses (PCAs) of the ion images were used to discriminate the conformation between the amorphous and flat‐on lamellar surfaces of the polymers. The changes of the surface structure were directly detected by time‐of‐flight secondary ion mass spectrometry chemical imaging when flat‐on lamellae were developed from the polymer melts. These structural changes were related to the lengths of the folded segments, which were strongly influenced by the crystallization temperature. The PCA loading analyses suggested that the length of the folded segments, which contained flexible and the rigid segments with an ether linkage, increased when the crystallization temperature decreased, suggesting the kinetic origin of polymer crystallization. Copyright © 2010 John Wiley & Sons, Ltd.
Surface and interface analysis of iodine‐doped pentacene structures for OTFTs
Authors: Jakabovič J. , Vincze A. , Kováč J. , Srnánek R. , Kováč J. , Dobročka E. , Donoval D. , Heinemeyer U. , Schreiber F. , Machovič V. , Uherek F.
Published: May 2010

We investigated the impact of iodine doping on structural properties of pentacene layers as a function of iodine concentration, which is controlled by the diffusion time. Furthermore, also the storing history of the samples is examined. We found that the iodine doping properties of pentacene samples strongly depend on the storing conditions (ambient atmosphere, time) before diffusion. We observed that the iodine diffusion process into pentacene layers is much faster for new recently prepared samples in contrast to old samples that were stored a few months at atmospheric ambient condition in the dark box before iodine diffusion. Copyright © 2010 John Wiley & Sons, Ltd.
High‐precision SIMS oxygen, sulfur and iron stable isotope analyses of geological materials: accuracy, surface topography and crystal orientation
Authors: Kita N. T. , Huberty J. M. , Kozdon R. , Beard B. L. , Valley J. W.
Published: May 2010

A high‐precision SIMS analysis technique has been established for oxygen, sulfur, and iron isotope ratios and applied to a wide range of geoscience research areas using a Cameca IMS‐1280 at the Wisconsin Secondary Ion Mass Spectrometer Laboratory (WiscSIMS). Precision and accuracy of 0.3‰is achieved routinely for the measurement of 18O/16O ratio using multicollection Faraday Cup (FC) detectors and primary Cs+ beam size of 10 µm. Smaller beam sizes of 3 µm to < 1 µm yield precisions of 0.7–2‰using a multicollection Electron Multiplier (EM) in pulse‐counting mode for 18O. We evaluate small SIMS analytical biases at the level of a few ‰or less using standard minerals with homogeneous oxygen isotope ratios: (i) topography of samples related to polishing relief of grains and location of analysis in a sample holder; and (ii) crystal orientation effects in magnetite (Fe3O4). The latter effect has not been detected for oxygen isotope ratio measurements in other minerals including a variety of silicate, oxide, and carbonate minerals at WiscSIMS. However, similar analytical biases that are correlated with crystal orientation have been identified from Fe isotope analyses in magnetite and S isotope analysis in sphalerite (ZnS), and many minerals have not yet been evaluated. The total range of analytical bias among randomly oriented magnetite grains becomes smaller by reducing the sputtering energy of the primary ions (from 20 to 10 keV), which may help reduce crystal orientation effects. Copyright © 2010 John Wiley & Sons, Ltd.
ToF‐SIMS depth profiling of vitamin C layers using Cs+ and Xe+ ion beams
Authors: Wehbe Nimer , Houssiau Laurent
Published: May 2010

Cesium (Cs+) and xenon (Xe+) sputter beams of energy ranging from 150 to 1000 eV were used to depth profile a 70 nm vitamin C layer spin‐coated on silicon wafer. We have shown that under Xe+ beam we were able to maintain the molecular information throughout the profile. In particular, the intensity of the deprotonated molecular ion (C6H7O6)− in the steady‐state regime was the highest compared to other characteristic fragments. When Cs+ is used instead of Xe+, the molecular signals decrease as the Cs+ fluence increases so that no steady state is reached whatever the cesium beam energy. However, the fingerprint, i.e. molecular and fragment ions assigned to the ascorbic acid molecule, could be maintained at 500 eV. The reason for such observations could be related to the reactivity of the cesium implanted in the organic layer. The dependence of the sputtering yield with the beam energy was found to be linear for both Cs+ and Xe+ beams. Copyright © 2010 John Wiley & Sons, Ltd.
Time‐of‐Flight secondary ion mass spectrometry (TOF‐SIMS) using the metal‐cluster‐complex primary ion of Ir4(CO)7+
Authors: Fujiwara Yukio , Saito Naoaki , Nonaka Hidehiko , Suzuki Atsushi , Nakanaga Taisuke , Fujimoto Toshiyuki , Kurokawa Akira , Ichimura Shingo
Published: May 2010

An orthogonal acceleration Time‐of‐Flight Secondary Ion Mass Spectrometer (TOF‐SIMS) system has been developed with a metal‐cluster‐complex ion source. The ion source can produce ion beams of massive molecules called metal‐cluster‐complexes such as Ir4(CO)12, which has a molecular weight higher than 1000 u. Using the system, TOF‐SIMS of a contaminated silicon substrate and a room temperature molten salt (i.e. an ionic liquid) was performed. The ionic liquid N,N‐diethyl‐N‐methyl‐N‐(2‐methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide, which has a molecular weight of 426 u, consists of a polyatomic cation, [C8H20ON]+, and a polyatomic anion, [C2F6NO4S2]−. During SIMS analysis, an analytical sample was bombarded with a continuous primary ion beam of either Ir4(CO)7+ or Ar+ in a beam energy of 10 keV at an incident angle of 45°. It was confirmed that the use of Ir4(CO)7+ ions enhanced secondary ion intensity compared with that of Ar+ ions. Also, experimental results showed that the bombardment of Ir4(CO)7+ caused less fragmentation. In the case of the ionic liquid, cation‐attached ionic‐liquid molecules were observed in addition to the cation of the ionic liquid. Copyright © 2010 John Wiley & Sons, Ltd.
ToF‐SIMS and PCA of surface‐immobilized antibodies with different orientations
Authors: Park Ji‐Won , Cho Il‐Hoon , Moon Dae Won , Paek Se‐Hwan , Lee Tae Geol
Published: May 2010

A number of studies have been done on the orientation of surface‐immobilized antibodies since it plays a significant role in the performance of immunoassays. Here, we present a new study by which the orientation of differently immobilized antibodies was directly probed by using time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and principal component analysis (PCA). For greater control over the orientations of intact IgG and F(ab′)2 antibody fragment, they were either site‐directly biotinylated at the hinge region or randomly biotinylated at the amino groups, and were then immobilized onto a streptavidin‐terminated surface. According to the PCA results from ToF‐SIMS spectra, site‐directly and randomly biotinylated IgG became ‘end‐on’ oriented (Fc is closer to the surface) at a gradual rate as immobilization concentration increased, while site‐directly biotinylated IgG became oriented at a slightly faster rate. Furthermore, site‐directly biotinylated F(ab′)2 quickly became ‘end‐on’ oriented even at a low concentration of 1 µg/ml as immobilization concentration increased, whereas randomly biotinylated F(ab′)2 was not oriented at all over any concentration. Our results show that a ToF‐SIMS partnership with multivariate analysis is useful for interpreting protein orientations in terms of surface amino acid profiles. Copyright © 2010 John Wiley & Sons, Ltd.
Surface morphology of PMMA surfaces bombarded with size‐selected gas cluster ion beams
Authors: Ichiki K. , Ninomiya S. , Nakata Y. , Yamada H. , Seki T. , Aoki T. , Matsuo J.
Published: May 2010

The surface morphology and sputtering rate of polymethylmethacrylate (PMMA) samples bombarded with size‐selected Ar cluster ion beam (1000–16 000 atoms/cluster) was investigated. The incident cluster ion size was selected before irradiation by using the time‐of‐flight (TOF) method. The sputtering rates decreased with increasing incident cluster size at constant total energy. The average surface roughness values measured by AFM after 25 nm etching with 20 keV Ar1000+ and Ar16 000+ were 4.0 ± 0.4 and 0.78 ± 0.09 nm, respectively. Thus, small clusters would be effective for high‐speed etching, and large clusters would be suitable for low‐damage etching. Copyright © 2010 John Wiley & Sons, Ltd.
Strategies for improving the sensitivity of FIB‐SIMS
Authors: Li Libing , McPhail David S. , Yakovlev Nikolai , Seng Hweeleng
Published: May 2010

Secondary ion yields need to be enhanced to provide higher sensitivity in the SIMS technique in order to meet the demands for high performance in surface analysis of ever‐decreasing analytical volumes. In this work, we investigated how the ionization probability could be improved by changing the surface chemistry prior to analysis by oxygen implantation and flooding. The ion‐induced altered layer was analyzed with the FIB‐SIMS and oxygen flooding was carried with the ION‐TOF IV. Copyright © 2010 John Wiley & Sons, Ltd.
Analysis of organic multilayered samples for optoelectronic devices by (low‐energy) dynamic SIMS
Authors: Ngo K. Q. , Philipp P. , Jin Y. , Morris S. E. , Shtein M. , Kieffer J. , Wirtz T.
Published: May 2010

The increasing sophistication of optoelectronic devices requires molecular‐level dimensional control in the fabrication of multilayered structures with specifically engineered interfaces. However, the effectiveness of growth and doping strategies devised to achieve the desired device structures often remains unverified due to the lack of adequate characterization techniques. This is particularly true for devices based on conjugated organic compounds, which find increasing use in energy applications (e.g. organic light emitting diodes and organic photovoltaic cells, etc.). The buried interfaces are simply inaccessible or suffer damage when using conventional characterization techniques. In a current project, we address this challenge by advancing the development of low‐energy (LE) SIMS for the analysis of organic‐based optoelectronic materials systems.

In the present study, multilayered organic thin films have been analyzed, varying experimental conditions such as the impact energies for Cs+ bombardment in the MCsx+ and M− mode on a Cameca Sc‐Ultra instrument to investigate the ionization mechanisms as well as the atomic mixing at the interfaces between layers, and the degradation of the organic information. Low‐energy dynamic SIMS proved to be a reliable tool for the characterization of organic multilayered optoelectronic devices: MCsx+ secondary ions provide information about the distribution of elements within the samples, while negative fragments that are characteristic for the different molecules give information about the structure. Copyright © 2010 John Wiley & Sons, Ltd.
Strontium distribution in bones and tissues of strontium ranelate‐administrated rats
Authors: Aranyosiova M. , Stancikova M. , Rovensky J. , Velic D.
Published: May 2010

Strontium accumulation and distribution are determined in bones of rats after strontium ranelate administration by using time‐of‐flight SIMS technique. Strontium ranelate is a newly developed drug effective in osteoporosis treatment by reducing bone resorption and promoting bone formation. The motivation is to study the strontium accumulation and distribution in bones and possible accumulations of strontium in soft tissues such as brain, liver and heart, are tested. The investigated rats are divided in the control group, one without strontium ranelate administration, and the other group of rats after five weeks of administration, with daily dose of 400 mg/kg. When the strontium ranelate‐treated bone samples are compared with the control, strontium is spectrally resolved and clearly identified within two‐dimensional distribution. Similar contours of calcium and strontium in two‐dimensional images support the hypothesis that strontium is capable of replacing calcium atoms as a part of the strontium ranelate mechanism in the osteoporosis treatment. Molecular ions, characteristic for biological samples as phospholipids, cholesterol and fatty acids are also identified. Strontium presence in heart, brain and liver tissues is not observed. Chemical characterization of biological samples in intact form without any chemical labeling by using SIMS could be, in this way, helpful in medical diagnostics. Copyright © 2010 John Wiley & Sons, Ltd.
Some surface and interface characterization and metrology requirements in the wafer processing industry
Authors: Brundle C. R.
Published: May 2010

With the rapid decrease in thickness of deposited layers during silicon wafer processing, there has been a parallel increase in the use of surface/interface materials analysis techniques. There is now little distinction between surface/interface and thin film analysis when films are only a few nm thick. This brief review presents some of the general concepts and needs for both materials characterization and metrology; some of the current requirements these needs impose on analytical methods; and briefly reviews the status of a few of the techniques better known to the surface/interface analysis community, particularly XPS. Copyright © 2010 John Wiley & Sons, Ltd.
High‐resolution XPS spectromicroscopy
Authors: Renault O.
Published: May 2010

The field of XPS imaging and spectromicroscopy has recently made significant progress thanks to laboratory X‐ray photoelectron emission microscopy (XPEEM), a novel, versatile parallel imaging method for which lateral resolution of core‐level images in the 500 nm range, and spectromicroscopy from decanometric‐size area of interest have been demonstrated (J. Electron Spectroc. Relat. Phenom. 171 (2009), 68). It uses a bright microfocussed monochromated Al Kα source and a photoelectron emission microscope (PEEM) as entrance lens of a high‐transmission, aberration‐compensated imaging spectrometer in the form of a double hemispherical analyzer. In this paper, restricted to laboratory aspects of XPS spectromicroscopy, we will first give some details of this novel instrumentation after a short historical review of the field until the presently existing imaging techniques. Then, some of the first results of laboratory core‐level XPEEM on practical samples will be presented. Future perspectives towards quantitative analysis, improvements of lateral resolution and multitechnique spectromicroscopic aspects with laboratory sources (including UPS spectromicroscopy in direct and reciprocal space) will be drawn. Copyright © 2010 John Wiley & Sons, Ltd.
Orientation of Si phthalocyanine investigated by X‐ray absorption spectroscopy and molecular orbital calculation
Authors: Sekiguchi Tetsuhiro , Baba Yuji , Shimoyama Iwao , Honda Mitsunori , Hirao Norie , Narita Ayumi , Deng Juzhi
Published: May 2010

We have investigated the orientation effect of silicon phthalocyanine dichloride evaporated on the highly oriented pyrolytic graphite (HOPG) surfaces using linearly polarized synchrotron radiation. Polarization angular dependences of Si 1s and Cl 1s near‐edge X‐ray absorption fine structure (NEXAFS) spectra were observed and compared with theoretical calculations based on equivalent core (Z + 1) approximation using the Hartree‐Fock molecular orbital method. The calculated properties are in agreement with the experimental spectra in symmetry, intensity and energy position. The intensities for the lowest energy peaks observed at both Si and Cl edges are enhanced when X‐ray electric field vector (E) is perpendicular to the surface. We assigned these peaks to out‐of‐plane transition into σz*(SiCl) final state orbital. We concluded that phthalocyanine plane is oriented parallel to the surface. Copyright © 2010 John Wiley & Sons, Ltd.
Recent developments in general system theory
Authors: Drack Manfred , Schwarz Gregor
Published: May 2010

Bertalanffy's general system theory (GST) was conceived as a unifying research program, as a science of ‘wholeness’ to overcome or complement mechanistic and reductionist approaches. More than 50 years since the founding of the Society for General Systems Research (SGSR), today's International Society for the Systems Sciences (ISSS), two questions arise about the developments in GST research. Are there recent contributions towards enhancing GST? Are there simplifications compared to Bertalanffy's original program? To answer these questions we analysed in detail 161 articles in peer reviewed journals that referred to GST and appeared between 1995 and 2006. We emphasized contributions made in science and philosophy. Even though the system approach was introduced in applied fields such as engineering and management, we did not include these fields in this article. Copyright © 2010 John Wiley & Sons, Ltd.
Association between different morphological types and abnormal karyotypes in early pregnancy loss
Authors: Angiolucci M. , Murru R. , Melis G. , Carcassi C. , Mais V.
Published: May 2010

Objectives

To identify the abnormal transvaginal ultrasound (TVS) findings typical of aneuploidic pregnancies that end with early pregnancy loss (EPL).

Methods

This was a prospective clinical trial over a 2½‐year period from January 2004 to June 2006 at the University Hospital of Cagliari, Italy. One hundred and fifty‐six singleton pregnancies with EPL were evaluated by TVS, both before and at the moment of EPL diagnosis. Fetal karyotyping was performed on products of conception using microsatellite analysis to exclude maternal contamination in 46,XX cases. The proportions of abnormal karyotypes were compared among different groups of EPLs characterized by different morphological features.

Results

Six morphological types were identified in EPLs, one normal and five abnormal (small gestational sac, small embryo/fetus, early symmetrical arrested growth, enlarged yolk sac and empty sac). The highest rate of chromosomal abnormalities was observed in the early symmetrical arrested growth group (100%), followed by small embryo/fetus (94.1%), enlarged yolk sac (93.3%) and empty sac (72.2%) groups. The majority of cases of trisomy 22 (92.3%) were in the enlarged yolk sac group and the majority of cases with a 45,X karyotype were in the small embryo/fetus group (77.8%).

Conclusions

There is an association in EPLs between some abnormal karyotypes and some morphological types. The demonstration by TVS of abnormalities in the development of early pregnancy structures could be helpful for predicting aneuploidy in EPLs. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Cervical sonography in pregnant women with a prior cone biopsy or loop electrosurgical excision procedure
Authors: Fischer R. L. , Sveinbjornsson G. , Hansen C.
Published: May 2010

Objectives

To determine if pregnant women with a prior cone biopsy or loop electrosurgical excision procedure (LEEP) have a shorter midtrimester cervical length than do matched controls without a history of cervical surgery.

Methods

Eighty‐five pregnant women with a singleton gestation and previous cone biopsy or LEEP and 85 controls matched by age ( ± 5 years), race, gestational age ( ± 2 weeks), and number of prior vaginal deliveries underwent a single transvaginal cervical sonographic scan at 15–22 weeks' gestation. No patient had a cerclage in either group.

Results

Mean cervical length was significantly shorter in the cone biopsy/LEEP group (3.3 vs. 3.9 cm, P < 0.001), with no significant difference in the proportion of cervical lengths less than 2.5 cm (5.9 vs. 2.4%). Gestational age at delivery was slightly but significantly lower in the cone biopsy/LEEP group (38.1 vs. 39.1 weeks, P = 0.005) than in the control group, with a higher proportion of women delivering late preterm and very preterm in the cone biopsy/LEEP group. However, no woman with a prior cone biopsy/LEEP experienced a midtrimester loss suggestive of cervical insufficiency, and no patient with a cervical length less than 2.5 cm delivered before 34 weeks' gestation.

Conclusions

Midtrimester cervical length in women with a previous cone biopsy or LEEP is significantly shorter than in those without prior cervical surgery. Based on the low frequency of a short cervix or midtrimester loss in women with prior excisional surgery, the routine use of midtrimester cervical sonography in such women is not supported. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Hepatic venous Doppler in the evaluation of fetal extrasystoles
Authors: Saemundsson Y. , Johansson C. , Wenling S. , Gudmundsson S.
Published: May 2010

Objectives

To evaluate the use of fetal hepatic venous Doppler in the diagnosis of fetal extrasystoles, to estimate the prevalence and persistence of extra atrial and ventricular heart beats throughout pregnancy, labor and delivery, and to estimate the frequency of coexisting congenital heart disease.

Methods

This was a retrospective study of 256 singleton pregnancies attending our hospital as outpatients due to fetal extrasystoles. Hepatic venous Doppler and detailed fetal echocardiography were performed. Information on fetal heart rate patterns during labor and neonatal conditions was collected. Congenital heart malformations and the frequency and persistence of fetal extrasystoles were noted.

Results

On venous Doppler examination, 228 (89%) of the fetuses showed signs of supraventricular extrasystoles (SVES) and 28 (11%) had ventricular extrasystoles (VES). One fetus with SVES developed atrial flutter during pregnancy and another case developed supraventricular tachycardia postnatally. SVES persisted until labor and delivery in 28 (12.3%) fetuses and VES persisted in six (21.4%). In 31 of 34 (91.2%) fetuses with extrasystoles during labor and delivery, the conduction pattern normalized within 3 days. Five neonates were referred for evaluation by a pediatric cardiologist. Two cases had congenital heart disease. Extrasystoles persisted until labor and delivery more frequently in male fetuses (P < 0.0001).

Conclusion

Hepatic venous Doppler can differentiate between SVES and VES. Despite being the more uncommon of the two, VES persists throughout pregnancy more often. Our results strongly support the suggestion that extrasystoles are a benign finding, with very few cases developing tachycardia or having a coexisting congenital heart malformation. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Reliability of the first‐trimester cardiac scan by ultrasound‐trained obstetricians with high‐frequency transabdominal probes in fetuses with increased nuchal translucency
Authors: Bellotti M. , Fesslova V. , De Gasperi C. , Rognoni G. , Bee V. , Zucca I. , Cappellini A. , Bulfamante G. , Lombardi C. M.
Published: May 2010

Objective

To examine prospectively the reliability of ultrasound‐trained obstetricians performing a first‐trimester fetal cardiac scan with high‐frequency transabdominal probes, by confirming normal or abnormal heart anatomy, in pregnancies referred for increased nuchal translucency thickness (NT).

Methods

Trained obstetric operators assessed the fetal heart in 133 fetuses with increased NT (> 95th centile) at 11–14 weeks of gestation. A high‐frequency transabdominal probe was used to confirm or refute normal cardiac anatomy rather than to establish a specific diagnosis. Following this preliminary screening by the ultrasound‐trained obstetrician, specialized fetal echocardiographers rescanned the fetal heart in order to confirm the accuracy of the obstetric operators' findings and to establish a diagnosis in abnormal cases. Fetal cardiologists repeated the examinations at 20 and 32 weeks of pregnancy. Postnatal follow‐up lasted 2 years. Twelve fetuses with normal karyotype and normal anatomy were lost to follow‐up.

Results

A total of 121 fetuses with increased NT between 11 and 14 weeks' gestation were studied. Congenital heart disease (CHD) was detected in 20/121 (16.5%) fetuses. In addition, there were three with mild ventricular disproportion, the right ventricle being larger than the left, considered as a minor non‐specific cardiac abnormality. CHD was associated with chromosomal anomalies in 12/20 (60%) cases. Among the 121 fetuses, there was agreement between ultrasound‐trained obstetricians and fetal cardiologists in 116 (95.9%) of the cases, and the ultrasound‐trained obstetricians correctly identified 18 cases with major cardiac defects. However, there was disagreement in five cases: two with small ventricular septal defects and three with ventricular disproportion.

Conclusions

Our results provide evidence that obstetricians, trained to study the heart in the second trimester, can also differentiate reliably between normal and abnormal heart findings in the first trimester, when using a high‐frequency transabdominal ultrasound probe. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Bayesian models of cognition
Authors: Chater Nick , Oaksford Mike , Hahn Ulrike , Heit Evan
Published: May 2010

There has been a recent explosion in research applying Bayesian models to cognitive phenomena. This development has resulted from the realization that across a wide variety of tasks the fundamental problem the cognitive system confronts is coping with uncertainty. From visual scene recognition to on‐line language comprehension, from categorizing stimuli to determining to what degree an argument is convincing, people must deal with the incompleteness of the information they possess to perform these tasks, many of which have important survival‐related consequences. This paper provides a review of Bayesian models of cognition, dividing them up by the different aspects of cognition to which they have been applied. The paper begins with a brief review of Bayesian inference. This falls short of a full technical introduction but the reader is referred to the relevant literature for further details. There follows reviews of Bayesian models in Perception, Categorization, Learning and Causality, Language Processing, Inductive Reasoning, Deductive Reasoning, and Argumentation. In all these areas, it is argued that sophisticated Bayesian models are enhancing our understanding of the underlying cognitive computations involved. It is concluded that a major challenge is to extend the evidential basis for these models, especially to accounts of higher level cognition. WIREs Cogn Sci 2010 1 811–823

This article is categorized under:

Psychology > Theory and Methods
Language evolution as cultural evolution: how language is shaped by the brain
Authors: Chater Nick , Christiansen Morten H.
Published: May 2010

This paper reviews arguments against the evolutionary plausibility of a traditional genetically specified universal grammar. We argue that no such universal grammar could have evolved, either by a process of natural selection or by other evolutionary mechanisms. Instead, we propose that the close fit between languages and language learners, which make language acquisition possible, arises not because humans possess a specialized biological adaptation for language, but because language has been shaped to fit the brain, a process of cultural evolution. On this account, many aspects of the structure of human languages may be explained as cultural adaptations to the human brain. Copyright © 2010 John Wiley & Sons, Ltd.

This article is categorized under:

Cognitive Biology > Evolutionary Roots of Cognition

Linguistics > Evolution of Language

Psychology > Language
Upper extremity surgery in younger children under ultrasound-guided supraclavicular brachial plexus block: A case series
Authors: Amiri Hamid Reza , Espandar Ramin
Published: May 2010

Purpose

Supraclavicular brachial plexus block is considered as one of the most effective anesthetic methods for upper extremity surgeries. Its major drawback, especially in children, is the risk of pneumothorax, vascular puncture, and failure of the procedure due to inaccurate placement of the needle. Ultrasound-guided needle placement may reduce the risk of complications and increase the accuracy of block, particularly in pediatric patients. There are few published experiences about the efficacy and safety of ultrasound-guided supraclavicular block in children and to our knowledge, it seems that there is no published report about its usage in younger children (less than 6 years of age).

Methods

In order to consider the efficacy of ultrasound in younger children, 17 patients aged between 6 months and 6 years were randomly selected. The ultrasound probe was used for proper placement of the needle. After confirmation of the needle location using a nerve locator, the anesthetic agent was injected. The procedure time, establishment time, duration of analgesia, any complications related to the procedure, and the surgeon's satisfaction were recorded and analyzed.

Results

The procedure time was 10.35 ± 1.22 min, the establishment time was 89.59 ± 18 s, and the duration of analgesia was between 6 and 16 h (mean 9.76 ± 2.57 h). The recovery time was 24.4 ± 6.5 min (range 15–37 min) and the duration of surgeries was 61.3 ± 25.9 min (range 15–110 min). There was no failure of the procedure. Also, there were no complications related to the procedure and the surgeon's satisfaction during surgery was good or excellent.

Conclusions

This study demonstrates the efficacy and safety of the ultrasound-guided supraclavicular brachial plexus block for orthopedic upper extremity surgeries in patients younger than 6 years of age.
Quartiersentwicklung 2030: Akteure, Einflussfaktoren und Zukunftstrends – Ergebnisse einer Delphi-Studie
Authors: Schnur Olaf , Markus Ilka
Published: May 2010

Der demographische Wandel sowie das Nebeneinander von schrumpfenden und wachsenden Wohnungsmarktregionen werden sich in Deutschland zunehmend auf die bisher wenig untersuchte Mesoebene des Wohnquartiers auswirken. Vor diesem Hintergrund wurden in einer 2007/2008 durchgeführten zweistufigen Delphi-Befragung mit dem Titel „DemographischerImpactin städtischen Wohnquartieren“ wesentliche Akteure, Einflussfaktoren und Zukunftstrends der Quartiersentwicklung erfasst und analysiert. In der Studie ging es um grundlegende Fragestellungen wie: Welche Quartiere werden zukünftig von den Auswirkungen des demographischen Wandels besonders betroffen sein? Was sind die Stärken und Schwächen einzelner Quartierstypen? Wie werden sich Wohnquartiere bis 2030 entwickeln? Welche Metatrends der Quartiersentwicklung zeichnen sich ab? Werden eher altersstrukturell homogene oder heterogene Quartiere bessere Entwicklungschancen haben?
Thinking beyond Peritoneal Carcinomatosis: Imaging Spectrum of Unusual Disseminated Peritoneal Entities
Authors: Fasih Najla , Galwa Ram P. , Macdonald David B. , Fraser-Hill Margaret A. , McInnes Matthew , Khalili Korosh
Published: May 2010

Although peritoneal carcinomatosis is the most common entity involving the peritoneum diffusely, a vast array of unusual diseases may affect the peritoneal surfaces. These entities can be further categorized into infectious, neoplastic, and miscellaneous conditions. Cross-sectional imaging, including computed tomography and magnetic resonance imaging are excellent modalities for further characterization of these unusual diseases. For some of these conditions, imaging-specific diagnosis is achievable. For others, the diagnosis can be favored when clinical and/or cross-sectional imaging features coexist.
Toward a Fully Automated High-Throughput Phototransfection System
Authors: Cappelleri David J. , Halasz Adam , Sul Jai-Yoon , Kim Tae Kyung , Eberwine James , Kumar Vijay
Published: May 2010

We have designed and implemented a framework for creating a fully automated high-throughput phototransfection system. Integrated image processing, laser target position calculation, and stage movements show a throughput increase of >23x over the current manual phototransfection method although the potential for even greater throughput improvements (>110x) is described. A software tool for automated off-line single-cell morphological measurements, as well as real-time image segmentation analysis, has also been constructed and shown to be able to quantify changes in the cell before and after the process, successfully characterizing them, using metrics such as cell perimeter, area, major and minor axis length, and eccentricity values.
Cells-to-CT Kits: Next Generation Gene Expression Analysis Workflows that Eliminate Sample Purification
Authors: Abruzzese Ron , Fekete Richard , Kephart Dan
Published: May 2010

Real-time reverse transcription PCR analysis of RNA expression in normal and diseased states is a fundamental technique used in research and screening workflows. However, traditional purification of RNA samples often represents a significant workflow bottleneck, which increases the time and automation complexity required for analysis. We describe the Cells-to-CT technology, a workflow that was designed in conjunction with real-time analysis to completely eliminate the need for traditional purification while maintaining performance relative to purified RNA. High-density sample preparation is accomplished in less than 8 min and is highly amenable to automation. We demonstrate that results are equivalent to RNA purified using traditional methods over a broad range of sample input while offering advantages when dealing with automated liquid handlers.
The role of idiosyncratic attribute evaluation in mass customization
Authors: Puligadda Sanjay , Grewal Rajdeep , Rangaswamy Arvind , Kardes Frank R.
Published: May 2010

The growing use of mass customization necessitates an understanding of consumers' evaluations of mass customization platforms. We hypothesize that consumers' objective and subjective knowledge of the customized product moderate the influence of idiosyncratically evaluated (i.e., personalizable) attributes on satisfaction with a customization platform. Consistent with our theoretical framework, results from three experiments show that offering greater variety in idiosyncratically evaluated attribute options increases consumers' satisfaction to a greater extent for: (1) novices than experts (2) consumers with more subjective knowledge, and (3) miscalibrated consumers whose subjective knowledge does not match their objective knowledge, than calibrated consumers whose subjective and objective knowledge match.
Imaging findings in 11 cats with feline dysautonomia
Authors: Novellas Rosa , Simpson Kerry E. , Gunn-Moore Danièlle A. , Hammond Gawain J.C.
Published: May 2010

Dysautonomia is caused by degeneration of the autonomic ganglia. Failure of the autonomic system affecting the gastrointestinal and urinary tracts can cause oesophageal distension and/or dysfunction, gastric and bowel distension and hypomotility, and urinary bladder distension. The aim of this retrospective study was to describe diagnostic imaging findings in cats with dysautonomia. Common findings were megaoesophagus and/or oesophageal dysfunction, gastric distension and signs of intestinal ileus. Associated aspiration pneumonia and megacolon appeared less commonly. Although diagnostic imaging findings are not specific for this disease, if findings in multiple systems are detected, along with consistent clinical signs and neurological deficits, dysautonomia should be considered among the differential diagnosis.
A Reappraisal of the Causes of Farm Protest in the United States, 1870–1900
Authors: Mayhew Anne
Published: May 2010

Between 1870 and 1900 American farmers organized in the Grange, the Alliances, and the Peoples (Populist) Party and protested against a variety of economic ills. Economic historians have generally explained the farm organizations and the protests in the same way that the farmers themselves explained them—in terms of low agricultural prices and high costs of inputs resulting in part from the monopolistic organization of the suppliers of those inputs. However, there now exists considerable evidence indicating that the economic conditions of the time were not: as the farmers depicted them, thus raising two questions: (1) if the farmers' statements about their economic state cannot be accepted as historical fact, then why were the farmers so angry? and (2) why did they choose to protest the issues which they did?
Interest Rates and Price Expectations During the Civil War
Authors: Roll Richard
Published: May 2010

Being a brief account of Northern money market conditions from 1861 through 1865, including representative empirical tables, together with yield curves and graphs, and containing speculations on the influence of gold.
American Reformers Abroad: The Kemmerer Missions in South America, 1923–1931
Authors: Seidel Robert N.
Published: May 2010

To be an expert was to assume a position of special significance in public life during and following the Progressive Era in America. To be trained in scientific principles of medicine, sociology, public administration, or economics was to be prepared to develop the opportunities and promises of American life and to reform those institutions and ideas that hindered progress. Some attention has been drawn to the limited use by government of professional academic economists starting in the early years of the twentieth century. But the work of American economists as advisers has generally been neglected, especially in relation to the study of American foreign relations. Focussing upon the work of Edwin W. Kemmerer in the five Andean countries of South America between 1923 and 1931, this article is an attempt to indicate the possibilities for fruitful research into various dimensions of foreign economic advising.