bluuebunny/crossref_metadata_2025_split huggingface dataset:
DNA Base Identification by Electron Microscopy
Authors: Bell David C. , Thomas W. Kelley , Murtagh Katelyn M. , Dionne Cheryl A. , Graham Adam C. , Anderson Jobriah E. , Glover William R. 
Published: October 2012

AbstractAdvances in DNA sequencing, based on fluorescent microscopy, have transformed many areas of biological research. However, only relatively short molecules can be sequenced by these technologies. Dramatic improvements in genomic research will require accurate sequencing of long (>10,000 base-pairs), intact DNA molecules. Our approach directly visualizes the sequence of DNA molecules using electron microscopy. This report represents the first identification of DNA base pairs within intact DNA molecules by electron microscopy. By enzymatically incorporating modified bases, which contain atoms of increased atomic number, direct visualization and identification of individually labeled bases within a synthetic 3,272 base-pair DNA molecule and a 7,249 base-pair viral genome have been accomplished. This proof of principle is made possible by the use of a dUTP nucleotide, substituted with a single mercury atom attached to the nitrogenous base. One of these contrast-enhanced, heavy-atom-labeled bases is paired with each adenosine base in the template molecule and then built into a double-stranded DNA molecule by a template-directed DNA polymerase enzyme. This modification is small enough to allow very long molecules with labels at each A-U position. Image contrast is further enhanced by using annular dark-field scanning transmission electron microscopy (ADF-STEM). Further refinements to identify additional base types and more precisely determine the location of identified bases would allow full sequencing of long, intact DNA molecules, significantly improving the pace of complex genomic discoveries.
The Nixon shock after forty years: the import surcharge revisited
Authors: IRWIN DOUGLAS A. 
Published: October 2012

AbstractOn 15 August 1971, President Richard Nixon closed the gold window and imposed a 10% surcharge on all dutiable imports in an effort to force other countries to revalue their currencies against the dollar. The import surcharge was lifted four months later after the Smithsonian agreement led to new exchange rate parities. This paper examines the political, economic, and legal issues surrounding this use of trade sanctions to achieve exchange rate adjustments.
Economic institutions: explanations for conformity and room for deviation
Authors: DEQUECH DAVID 
Published: October 2012

AbstractWhy do economic agents conform with existing institutions? Drawing on economics and organizational institutionalism, this article identifies existing explanations, extends or refines some of them, suggests new ones, classifies these various explanations, and integrates them into an organized framework. One set of explanations focuses on conformity out of habit. The other refers to more conscious thought and behavior and considers coordination and increasing returns to adoption, social sanctions, informational differences, uncertainty, legitimacy, naturality, and lack of power/resources to deviate.
Measuring institutions: how to be precise though vague
Authors: SHIRLEY MARY M. 
Published: October 2012

Abstract:In his article on measuring institutions, Stephan Voigt (2012) proposes a pragmatic approach to develop more concrete, objective institutional variables than the broad abstractions used in most cross-country growth regressions. Voigt's approach has important strengths, but cross-country growth regressions, even with precisely measured institutions, are less likely to yield new insights than other methodologies.
Relationships between Δ14C and the molecular quality of dissolved organic carbon in rivers draining to the coast from the conterminous United States
Authors: Butman David , Raymond Peter A. , Butler Kenna , Aiken George 
Published: October 2012

Dissolved organic carbon (DOC) in natural waters possesses chemical and molecular qualities indicative of its source and age. The apportionment of DOC by age into millennial and decadal pools is necessary to understand the temporal connection between terrestrial and aquatic ecosystems in the global carbon cycle. We measured Δ14C‐DOC and chemical composition indices (specific ultraviolet absorbance (SUVA254), fluorescence index (FI), hydrophobic organic acid fraction (HPOA) content) for 15 large river basins in the conterminous United States. Across all rivers the average proportion of HPOA in DOC correlated strongly with SUVA254 (r2 = 0.93 p < 0.001). Individual Δ14C‐DOC ranged from a low of −92.9‰ (726 y.b.p.) in the Colorado River to 73.4‰ (>Modern) in the Altamaha River for the year 2009. When adjusted by total discharge, these U.S. Rivers export modern carbon at between 34 and 46‰, a signal dominated by the Mississippi River. The variation in Δ14C correlates to indices of the aromaticity of the DOC measured by the SUVA254 (r2 = 0.87, p < 0.001), and FI (r2 = 0.6; p < 0.001) as well as differences in annual river discharge (r2 = 0.46, p < 0.006). SUVA254 was further correlated to broad scale vegetation phenology estimated from the Enhanced Vegetation Index derived from the NASA Moderate Resolution Imaging Spectrometer (MODIS). We show that basins with high discharge, high proportions of vegetation cover, and low human population densities export DOC enriched in aromatic material that corresponds to recently fixed atmospheric CO2. Conversely old DOC is exported from low discharge watersheds draining arid regions, and watersheds more strongly impacted by humans. The potential influence from fossil carbon from human inputs to aquatic systems may be important and requires more research.
Formation of recurring slope lineae by liquid brines on present‐day Mars
Authors: Chevrier Vincent F. , Rivera‐Valentin Edgard G. 
Published: October 2012

Recurring Slope Lineae (RSL) are small scale seasonal flow features identified by Mars Reconnaissance Orbiter that present several interesting characteristics such as an albedo contrast, seasonal dependence, and a strong preference for equator‐facing slopes. All of these characteristics strongly suggest a thermally driven mechanism such as a liquid triggered or dominated flow. Here we investigate the possibility that these features are formed by melting of brines of various compositions via a combination of thermodynamic and kinetic numerical models. Results suggest that a solution with a freezing temperature of ∼223 K can best reproduce the observed seasonality. Relatively high surface evaporation rates at the RSL locations make the flows quickly disappear over a single season. Our model reproduces well the seasonality of RSL and can explain the preference for equator‐facing slopes suggesting that brine flows, and therefore liquids, are possible on a small time and space scale today on Mars. However, if the RSL are indeed formed by brines, it may indicate that a recharge mechanism is active in order to maintain a source of brine over even short geological timescales, which would have important implications for the Martian water cycle.
Comparison of dynamically and statistically downscaled seasonal climate forecasts for the cold season over the United States
Authors: Yoon Jin‐Ho , Ruby Leung L. , Correia James 
Published: October 2012

This study compares two approaches, dynamical and statistical downscaling, for their potential to improve regional seasonal forecasts for the United States (U.S.) during the cold season. In the MultiRCM Ensemble Downscaling (MRED) project, seven regional climate models (RCMs) are used to dynamically downscale the Climate Forecast System (CFS) seasonal prediction over the conterminous U.S. out to 5 months for the period of 1982–2003. The simulations cover December to April of next year with 10 ensemble members from each RCM with different initial and boundary conditions from the corresponding ensemble members. These dynamically downscaled forecasts are compared with statistically downscaled forecasts produced by two bias correction methods applied to both the CFS and RCM forecasts. Results of the comparison suggest that the RCMs add value in seasonal prediction application, but the improvements largely depend on location, forecast lead time, variables, and skill metrics used for evaluation. Generally, more improvements are found over the Northwest and North Central U.S. for the shorter lead times. The comparison results also suggest a hybrid forecast system that combines both dynamical and statistical downscaling methods have the potential to maximize prediction skill.
Computer-Based and Paper-Based Reading Comprehension in Adolescents With Typical Language Development and Language-Learning Disabilities
Authors: Srivastava Pradyumn , Gray Shelley 
Published: October 2012

PurposeWith the global expansion of technology, our reading platform has shifted from traditional text to hypertext, yet little consideration has been given to how this shift might help or hinder students' reading comprehension. The purpose of this study was to compare reading comprehension of computer-based and paper-based texts in adolescents with and without language-learning disabilities (LLD).MethodFourteen adolescents with LLD and 25 adolescents with typical language development (TLD) read literary texts in computer-based and paper-based formats and then answered reading comprehension questions.ResultsThe LLD group scored significantly lower than the TLD group on the reading comprehension measure, but there were no significant between-group differences for reading or answering time. In addition, there were no significant within-group differences for the computer-based or paper-based conditions. Predictors for reading comprehension varied by group and condition.ConclusionNeither group appeared to be affected by the additional cognitive load imposed by hypertext in the computer-based condition; however, the load between conditions may not have been sufficient to differentially impact reading comprehension. Based on the regression analyses, it appears that working memory, oral language, and decoding differed in their contribution to reading comprehension for each group and condition.
Stuttering in School-Age Children: A Comprehensive Approach to Treatment
Authors: Yaruss J. Scott , Coleman Craig E. , Quesal Robert W. 
Published: October 2012

Purpose

This letter, prepared through a close collaboration between the authors and more than 100 colleagues, responds to a paper by the editor of
Language, Speech, and Hearing Services in Schools
that highlighted the need for research on treatment for stuttering in school-age children.

Method

Our response addresses 3 themes: First, we offer agreement with the editor’s call for research because more evidence about treatment for children who stutter is certainly needed. Second, we provide an overview of recent literature, demonstrating that the majority of current treatments include strategies for helping children improve speech fluency
in addition to
helping them increase acceptance of their stuttering and diminish the negative consequences of the disorder. Third, we present several strategies designed to help clinicians respond to the individual needs of children who stutter in a data-based, comprehensive manner that focuses on minimizing the adverse impact of stuttering on children’s educational endeavors, and on their lives as a whole.

Conclusion
Much has been learned about the factors that contribute to the successful treatment of stuttering in school-age children, and evidence will continue to accumulate. Meanwhile, speech-language pathologists can help children increase their fluency while simultaneously minimizing the adverse impact of their speaking difficulties and helping them improve their overall communication.
Training Secondary School Teachers in Instructional Language Modification Techniques to Support Adolescents With Language Impairment: A Randomized Controlled Trial
Authors: Starling Julia , Munro Natalie , Togher Leanne , Arciuli Joanne 
Published: October 2012

PurposeThis study evaluated the efficacy of a collaborative intervention where a speech-language pathologist (SLP) trained mainstream secondary school teachers to make modifications to their oral and written instructional language. The trained teachers' uptake of techniques in their whole-class teaching practices and the impact this had on the language abilities of students with language impairment (LI) were evaluated.MethodTwo secondary schools were randomly assigned to either a trained or a control condition. A cohort of 13 teachers (7 trained and 6 control) and 43 Year 8 students with LI (21 trained and 22 control) were tested at pre, post, and follow-up times—teachers by structured interview and students by standardized spoken and written language assessments.ResultsSignificantly increased use of the language modification techniques by the trained teachers was observed when compared to the control group of untrained teachers, with this increased use maintained over time. Results from the trained group of students showed a significant improvement in written expression and listening comprehension relative to the control group of students.ConclusionThis randomized controlled trial is one of the first investigations to evaluate a collaborative intervention that links changes in mainstream secondary teachers' instructional language practices with improvements in the language abilities of adolescents with LI.
When a School-Age Child Stutters, Let’s Focus on the Primary Problem
Authors: Nippold Marilyn A. 
Published: October 2012

Purpose
In this reply to Yaruss, Coleman, and Quesal (2012), I explain why it is reasonable for speech-language pathologists to focus their attention on helping school-age children who stutter (CWS) achieve natural-sounding fluent speech. I also emphasize the necessity for clinical researchers to conduct high-quality treatment efficacy studies of school-age CWS.
Counting single photoactivatable fluorescent molecules by photoactivated localization microscopy (PALM)
Authors: Lee Sang-Hyuk , Shin Jae Yen , Lee Antony , Bustamante Carlos 
Published: October 2012

We present a single molecule method for counting proteins within a diffraction-limited area when using photoactivated localization microscopy. The intrinsic blinking of photoactivatable fluorescent proteins mEos2 and Dendra2 leads to an overcounting error, which constitutes a major obstacle for their use as molecular counting tags. Here, we introduce a kinetic model to describe blinking and show that Dendra2 photobleaches three times faster and blinks seven times less than mEos2, making Dendra2 a better photoactivated localization microscopy tag than mEos2 for molecular counting. The simultaneous activation of multiple molecules is another source of error, but it leads to molecular undercounting instead. We propose a photoactivation scheme that maximally separates the activation of different molecules, thus helping to overcome undercounting. We also present a method that quantifies the total counting error and minimizes it by balancing over- and undercounting. This unique method establishes that Dendra2 is better for counting purposes than mEos2, allowing us to count in vitro up to 200 molecules in a diffraction-limited spot with a bias smaller than 2% and an uncertainty less than 6% within 10 min. Finally, we demonstrate that this counting method can be applied to protein quantification in vivo by counting the bacterial flagellar motor protein FliM fused to Dendra2.
Effect of Feeding–Fasting Cycles on Oxygen Consumption and Bioenergetics of Female Yellow Perch
Authors: Schaeffer Travis W. , Spengler Daniel E. , Schoenebeck Casey W. , Brown Michael L. , Chipps Steven R. 
Published: October 2012

AbstractWe measured growth and oxygen consumption of age‐1 yellow perch Perca flavescens subjected to ad libitum (control) or variable feeding cycles of 2 (i.e., 2 d of feed, 2 d of deprivation), 6, or 12 d for a 72‐d period. Individual, female yellow perch (initial weight = 51.9 ± 0.9 g [mean ± SE]) were stocked in 110‐L aquaria to provide six replicates per treatment and fed measured rations of live fathead minnow Pimephales promelas. Consumption, absolute growth rate, growth efficiency, and oxygen consumption were similar among feeding regimens. However, growth trajectories for fish on the 2‐d cycle were significantly lower than other feed–fast cycles. Hyperphagia occurred in all treatments. Bioenergetics model simulations indicated that consumption was significantly underestimated (t = 5.4, df = 4, P = 0.006), while growth was overestimated (t = −5.5, df = 4, P = 0.005) for fish on the 12‐d cycle. However, model errors detected between observed and predicted values were low, ranging from −10.1% to +7.8%. We found that juvenile yellow perch exhibited compensatory growth (CG), but none of the feed–fast treatments resulted in growth overcompensation. Likewise, we found no evidence that respiration rates varied with CG, implying that yellow perch bioenergetics models could be used to predict the effects of feeding history and CG response on food consumption and fish growth.
Enhanced capacitance ratio and low minimum capacitance of varactor devices based on depletion-mode Ga-doped ZnO TFTs with a drain-offset structure
Authors: Remashan K , Choi Y S , Park S J , Jang J H 
Published: October 2012

Abstract
Depletion-mode Ga-doped ZnO thin-film transistors (TFTs) with a drain-offset configuration were fabricated employing a plasma-enhanced chemical vapour deposited Si3N4 gate insulator and a metal organic chemical vapour deposition grown Ga-doped ZnO channel layer. For comparison, conventional TFTs with drain-to-gate overlap were also fabricated. Capacitance–voltage characteristics of gate-to-drain capacitors and current–voltage characteristics of TFTs were measured. Although drain-offset TFTs exhibit poor device characteristics compared with conventional TFTs, these TFTs show better C
max/C
min ratio and C
min values. The C
max/C
min ratio is as large as 71.83 and C
min is as small as 0.3 fF µm−1 normalized for channel width, demonstrating the potential of these devices as varactors for circuit applications. Their better varactor performance is ascribed to the presence of a very small capacitance in the drain-offset region. The effect of drain-offset length variation on TFT and gate-to-drain capacitor performance is also reported.
Study of ultrasound-assisted radio-frequency plasma discharges in n-dodecane
Authors: Camerotto Elisabeth , Schepper Peter De , Nikiforov Anton Y , Brems Steven , Shamiryan Denis , Boullart Werner , Leys Christophe , Gendt Stefan De 
Published: October 2012

Abstract
This paper investigates the generation of a stable plasma phase in a liquid hydrocarbon (n-dodecane) by means of ultrasound (US) and radio-frequency (RF) or electromagnetic radiation. It is demonstrated for the first time that ultrasonic aided RF plasma discharges can be generated in a liquid. Plasma discharges are obtained for different gas mixtures at a pressure of 12 kPa and at low ignition powers (100 W for RF and 2.4 W cm−2 for US). Direct carbon deposition from the liquid precursor on Cu, Ni, SiO2 and Si substrates has been obtained and no apparent compositional or structural difference among the substrate materials was observed. Characterization of the deposited solid phase revealed an amorphous structure. In addition, structural changes in the liquid precursor after plasma treatment have been analysed. Optical emission spectroscopy (OES) allowed the estimation of several plasma characteristic temperatures. The plasma excitation temperature was estimated to be about 2.3–2.4 eV. The rotational and vibrational temperatures of the discharge in n-dodecane with Ar as a feed gas were 1400 K and 6500 K, respectively. In Ar/O2 plasma, an increased rotational (1630 K) and vibrational temperature (7200 K) were obtained.
Shack–Hartmann type laser wavefront sensor for measuring two-dimensional electron density distribution over extinguishing arc discharge
Authors: Inada Yuki , Matsuoka Shigeyasu , Kumada Akiko , Ikeda Hisatoshi , Hidaka Kunihiko 
Published: October 2012

Abstract
Shack–Hartmann type laser wavefront sensors were developed for measuring a two-dimensional electron density distribution over an arc channel in an extinguishing phase by only a single measurement with high temporal and spatial resolutions. The sensors were applied to pulsed arcs in a 3 mm air gap between rod-to-rod tungsten electrodes with a diameter of 1mm. Electron densities in the arc discharges with currents of several tens of amperes were 2 × 1023 m−3 around the gap centre, which were more than twice lower than those near the anode and cathode.
Characterization of nucleation and growth kinetics of the formation of water-soluble CdSe quantum dots by their optical properties
Authors: Mi Wen , Tian Jintao , Jia Jinqian , Tian Weiguo , Dai Jinhui , Wang Xin 
Published: October 2012

Abstract
The nucleation and growth kinetics of the formation of water-soluble CdSe quantum dots (QDs) was characterized by measurements of their optical properties of ultraviolet–visible and fluorescence spectra. The QDs were synthesized using thioglycolic acid as a capping agent. Two kinetic parameters, reaction temperature and time, were varied over wide ranges 20–90 °C and 0–12 h, respectively. Our results showed that a low reaction temperature was preferable for the nucleation process, resulting in relatively small particles and a narrow size distribution. The subsequent grain growth was mainly achieved within 1 h. The reaction temperature virtually affected the kinetic features of the QDs. The fluorescence measurements revealed largest variations of the fluorescence features for the 70 °C samples. From a viewpoint of controls of fluorescence colour and intensity over a wide range, a reaction temperature of 70 °C was appropriate for the CdSe QD synthesis.
An investigation of the growth of bismuth whiskers and nanowires during physical vapour deposition
Authors: Stanley S A , Stuttle C , Caruana A J , Cropper M D , Walton A S O 
Published: October 2012

Abstract
Bismuth thin films of thickness in the region of 500 nm have been prepared by planar magnetron sputtering onto glass, silicon and GaAs substrates. Electron microscopy of these films reveals that bismuth whiskers grow spontaneously when the substrate is heated to temperatures between 110 and 140 °C during deposition and the optimum temperature for such growth is largely independent of substrate. Depositing films under similar conditions using thermal evaporation does not, however, produce the whisker growth. X-ray diffraction has been employed to investigate film texture with temperature and it has been shown that the film crystallites are predominantly [1 1 0] and [1 1 1] oriented. The [1 1 0] orientation of the crystallites dominates at deposition temperatures above 110 °C for sputter deposition and the [1 1 1] at lower temperatures. The optimum temperature for whisker growth coincides with the temperature for the change between predominant orientations. While sputter deposition appears to favour films with crystallite orientation of [1 1 0], thermal evaporation favours [1 1 1] and has a higher change-over temperature. The whiskers that grow from the film emerge at off-normal angles between 43.3° and 69.2° with a mean of 54 ± 3°. The projected length of whiskers on a 500 nm film on a GaAs substrate shows a wide distribution to a maximum of more than 100 µm. The mean projected length for this sample was 16 ± 1 µm and the diameter is around 0.5 µm. Measurements of the electrical properties of the whiskers at room temperature reveals ohmic behaviour with an estimated resistivity of 2.2 ± 0.2 µΩ m. Detailed examination of scanning electron micrographs, eliminates all growth mechanisms except tip growth by a non-catalysed vapour–solid/vapour–liquid–solid method. By depositing thinner films it is shown that this spontaneous growth of whiskers offers a route to fabricate high quality bismuth nanowires of lengths exceeding 10 µm.