bluuebunny/crossref_metadata_2025 huggingface dataset:
Somatic instability of CTG repeats in the cerebellum of myotonic dystrophy type 1
Authors: Jinnai Kenji , Mitani Maki , Futamura Naonobu , Kawamoto Kunihiko , Funakawa Itaru , Itoh Kyoko
Published: November 2012

Introduction: We statistically analyzed somatic instability of the CTG expansion in the central nervous system and visceral organs in 7 patients with myotonic dystrophy type 1 and also report intracerebellar instability in 2 patients. Methods: CTG repeat expansion was estimated in the samples from autopsied brains and visceral organs by Southern blot analysis. Pathological study was performed. Samples were taken from several sites in the cerebellum to examine intracerebellar instability. Results: The CTG repeat expansion was shortest in the cerebellar cortex among all tissues examined. With regard to the intracerebellar difference, the shortest expansion was seen in the cortices of the hemisphere and vermis, whereas it was moderate in the dentate nucleus and longest in the white matter of the hemisphere and middle cerebellar peduncle. Conclusions: The shortest expansion might be attributable to packed granule cells in the cerebellar cortex. Further analysis of cell‐specific methylation states might elucidate the enigma of somatic instability. Muscle Nerve, 2013
Sonographic evaluation of vascular pulmonary reactivity following oxygen administration in fetuses with normal lung development
Authors: DeKoninck Philip , Lewi Paul , Done Elisa , Richter Jute , Gucciardo Léonardo , Mieghem Tim Van , Deprest Jan A.
Published: November 2012

Objective

This study aimed to establish nomograms for sonographic assessment of fetal pulmonary vascular reactivity following maternal hyperoxygenation.

Study design

Sixty‐two healthy fetuses were assessed at four weekly intervals from 26 weeks onwards. Pulmonary reactivity was evaluated using Doppler ultrasound in the main pulmonary artery and in the first branch of this main pulmonary artery. The difference in pulsatility index (∆PI) during maternal inhalation of a mixture of room air and oxygen (9 L/min) for at least 10 min was expressed as a percentage. Nomograms were constructed, and Kaplan–Meier curves were used to express the occurrence of a reactive test (∆PI ≥ 20%) with advancing gestation.

Results

In the first branch, linear regression analysis revealed a significant correlation of ∆PI (%) with gestational age (r2 = 0.04, p = 0.0057). Large inter‐individual and intra‐individual variability was noted. The ∆PI (%) in the main pulmonary artery remained constant throughout gestation (6.62 ± 17.83%).

Conclusion

Vascular reactivity in the pulmonary circulation increases in the first branch of the pulmonary artery. Large individual variability is limiting its use as a management tool. © 2012 John Wiley & Sons, Ltd.
Microfluidic devices for high‐throughput proteome analyses
Authors: Chao Tzu‐Chiao , Hansmeier Nicole
Published: November 2012

Over the last decades, microfabricated bioanalytical platforms have gained enormous interest due to their potential to revolutionize biological analytics. Their popularity is based on several key properties, such as high flexibility of design, low sample consumption, rapid analysis time, and minimization of manual handling steps, which are of interest for proteomics analyses. An ideal totally integrated chip‐based microfluidic device could allow rapid automated workflows starting from cell cultivation and ending with MS‐based proteome analysis. By reducing or eliminating sample handling and transfer steps and increasing the throughput of analyses these workflows would dramatically improve the reliability, reproducibility, and throughput of proteomic investigations. While these complete devices do not exist for routine use yet, many improvements have been made in the translation of proteomic sample handling and separation steps into microfluidic formats. In this review, we will focus on recent developments and strategies to enable and integrate proteomic workflows into microfluidic devices.
Development and Performance of the W/Sb2O3/KIO4/Lubricant Pyrotechnic Delay in the US Army Hand‐Held Signal
Authors: Poret Jay C. , Shaw Anthony P. , Csernica Christopher M. , Oyler Karl D. , Estes Deven P.
Published: November 2012

Gassy pyrotechnic delays composed of tungsten, antimony(III) oxide, potassium periodate, and various lubricants have been developed for use in the US Army hand‐held signal. The new compositions were developed to replace the current formulation, which contains potassium perchlorate and barium chromate, chemicals that are facing increasing scrutiny due to environmental regulation. The hand‐held signal delay housing was used to demonstrate the burning rate tunability of the new compositions. The addition of 1–5 % of waxy lubricants (stearic acid or calcium stearate) was found to have a profound effect on burning rate. The effect of tungsten content and the Sb2O3/KIO4 ratio on burning rate was also probed. A wide range of inverse burning rates (2 to 15 s cm−1) were demonstrated, which encompasses the 7 to 8.5 s cm−1 range required by the hand‐held signal. The W/KIO4 reaction produces I2, which was observed by visible spectroscopy in the vapor above a sample of combustion residue.
Curcumin Serves as a Human Kv1.3 Blocker to Inhibit Effector Memory T Lymphocyte Activities
Authors: Lian Yi‐Tian , Yang Xiao‐Fang , Wang Zhao‐Hui , Yang Yong , Yang Ying , Shu Yan‐Wen , Cheng Long‐Xian , Liu Kun
Published: November 2012

Curcumin, the principal active component of turmeric, has long been used to treat various diseases in India and China. Recent studies show that curcumin can serve as a therapeutic agent for autoimmune diseases via a variety of mechanisms. Effector memory T cells (TEM, CCR7‐CD45RO+ T lymphocyte) have been demonstrated to play a crucial role in the pathogenesis of T cell‐mediated autoimmune diseases, such as multiple sclerosis (MS) or rheumatoid arthritis (RA). Kv1.3 channels are predominantly expressed in TEM cells and control TEM activities. In the present study, we examined the effect of curcumin on human Kv1.3 (hKv1.3) channels stably expressed in HEK‐293 cells and its ability to inhibit proliferation and cytokine secretion of TEM cells isolated from patients with MS or RA. Curcumin exhibited a direct blockage of hKv1.3 channels in a time‐dependent and concentration‐dependent manner. Moreover, the activation curve was shifted to a more positive potential, which was consistent with an open‐channel blockade. Paralleling hKv1.3 inhibition, curcumin significantly inhibited proliferation and interferon‐γ secretion of TEM cells. Our findings demonstrate that curcumin is able to inhibit proliferation and proinflammatory cytokine secretion of TEM cells probably through inhibition of hKv1.3 channels, which contributes to the potency of curcumin for the treatment of autoimmune diseases. This is probably one of pharmacological mechanisms of curcumin used to treat autoimmune diseases. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of Methyl and Isopropyl N‐methylanthranilates from Choisya ternata Kunth (Rutaceae) on Experimental Anxiety and Depression in Mice
Authors: Radulović Niko S. , Miltojević Ana B. , Randjelović Pavle J. , Stojanović Nikola M. , Boylan Fabio
Published: November 2012

Choisya ternata Kunth (Rutaceae) is a plant species used in Mexican folk medicine for its antispasmodic and simulative properties. Recently, we identified a new alkaloid, isopropyl N‐methylanthranilate, and a related one, methyl N‐methylanthranilate, from the essential oil of this species and have proven them to possess antinociceptive activity even at 0.3 mg/kg. In the present study, anxiolytic and antidepressant effects of the two compounds have been studied in open field, horizontal wire, light/dark, forced swimming and tail suspension tests, as well as the effect on the onset and duration of diazepam‐induced sleep in BALB/c mice. The volatile alkaloids (50–200 mg/kg, administered intraperitoneally), without having a muscle relaxant effect, caused a significant increase in the time the animals spent in an unsecured and putatively dangerous area when compared with the control group but had no effect on the number of crossings between the light/dark compartments. In addition to this anxiolytic activity, a significantly antidepressant‐like effect was apparent at all tested doses, which was not due to an increase in locomotive activity. The anthranilates administered on their own did not induce sleep in mice but significantly prolonged the diazepam‐induced sleep, in a dose‐dependent way, suggesting an interaction with the gamma‐aminobutyric acid receptor complex. Copyright © 2012 John Wiley & Sons, Ltd.
IKE vulnerability discovery based on fuzzing
Authors: Yang Huan , Zhang Yuqing , Hu Yu‐pu , Liu Qi‐xu
Published: November 2012

Internet Key Exchange (IKE) protocol is widely applied on the Internet to protect confidentiality of the Internet communication. However, there are many high‐risk security vulnerabilities in various IKE implementations. Traditional fuzzing approaches with the aim of discovering vulnerabilities have some blind spots, such as time‐consuming, low efficiency, and low degree of automation. This paper introduces a new vulnerability discovering approach based on fuzzing and applies the approach to the IKE protocol. Through summarizing the most comprehensive vulnerable points of IKE protocol and proposing a two‐stage test cases library, an IKE protocol vulnerability discovering tool called IKEProFuzzer is designed and implemented. It is a network protocol fuzzing framework with extensibility and automated Monitor/Debugger designed by ourselves. In the experiments, IKEProFuzzer has discovered 14 vulnerabilities, including nine released vulnerabilities and five unreleased ones, which affect many kinds of routers and applications. The evaluation results prove the feasibility, efficiency, and extensibility of the approach compared with the existing approaches. Copyright © 2012 John Wiley & Sons, Ltd.
Brief Report: Self-Organizing Neuroepithelium from Human Pluripotent Stem Cells Facilitates Derivation of Photoreceptors
Authors: Boucherie Cédric , Mukherjee Sayandip , Henckaerts Els , Thrasher Adrian J. , Sowden Jane C. , Ali Robin R.
Published: November 2012

Retinitis pigmentosa, other inherited retinal diseases, and age-related macular degeneration lead to untreatable blindness because of the loss of photoreceptors. We have recently shown that transplantation of mouse photoreceptors can result in improved vision. It is therefore timely to develop protocols for efficient derivation of photoreceptors from human pluripotent stem (hPS) cells. Current methods for photoreceptor derivation from hPS cells require long periods of culture and are rather inefficient. Here, we report that formation of a transient self-organized neuroepithelium from human embryonic stem cells cultured together with extracellular matrix is sufficient to induce a rapid conversion into retinal progenitors in 5 days. These retinal progenitors have the ability to differentiate very efficiently into Crx+ photoreceptor precursors after only 10 days and subsequently acquire rod photoreceptor identity within 4 weeks. Directed differentiation into photoreceptors using this protocol is also possible with human-induced pluripotent stem (hiPS) cells, facilitating the use of patient-specific hiPS cell lines for regenerative medicine and disease modeling.
Gata4 Blocks Somatic Cell Reprogramming By Directly Repressing Nanog
Authors: Serrano Felipe , Calatayud Carles F. , Blazquez Marina , Torres Josema , Castell Jose V. , Bort Roque
Published: November 2012

Somatic cells can be reprogrammed to induced pluripotent stem (iPS) cells by ectopic expression of the four factors Oct4, Klf4, Sox2, and Myc. Here, we investigated the role of Gata4 in the reprogramming process and present evidence for a negative role of this family of transcription factors in the induction of pluripotency. Coexpression of Gata4 with Oct4, Klf4, and Sox2 with or without Myc in mouse embryonic fibroblasts greatly impaired reprogramming and endogenous Nanog expression. The lack of Nanog upregulation was associated with a blockade in the transition from the initiation phase of reprogramming to the full pluripotent state characteristic of iPS cells. Addition of Nanog to the reprogramming cocktail blocked the deleterious effects observed with Gata4 expression. Downregulation of endogenous Gata4 by short hairpin RNAs during reprogramming both accelerated and increased the efficiency of the process and augmented the mRNA levels of endogenous Nanog. Using comparative genomics, we identified a consensus binding site for Gata factors in an evolutionary conserved region located 9 kb upstream of the Nanog gene. Using chromatin immunoprecipitation, gel retardation, and luciferase assays, we found that Gata4 bound to this region and inhibited Nanog transcription in mouse embryonic stem cells. Overall, our results describe for first time the negative effect of Gata4 in the reprogramming of somatic cells and highlight the role of Gata factors in the transcriptional networks that control cell lineage choices in the early embryo.
Effective Elimination of Cancer Stem Cells By a Novel Drug Combination Strategy
Authors: Yuan Shuqiang , Wang Feng , Chen Gang , Zhang Hui , Feng Li , Wang Lei , Colman Howard , Keating Michael J. , Li Xiaonan , Xu Rui-Hua , Wang Jianping , Huang Peng
Published: November 2012

Development of effective therapeutic strategies to eliminate cancer stem cells, which play a major role in drug resistance and disease recurrence, is critical to improve cancer treatment outcomes. Our study showed that glioblastoma stem cells (GSCs) exhibited low mitochondrial respiration and high glycolytic activity. These GSCs were highly resistant to standard drugs such as carmustine and temozolomide (TMZ), but showed high sensitivity to a glycolytic inhibitor 3-bromo-2-oxopropionate-1-propyl ester (3-BrOP), especially under hypoxic conditions. We further showed that combination of 3-BrOP with carmustine but not with TMZ achieved a striking synergistic effect and effectively killed GSCs through a rapid depletion of cellular ATP and inhibition of carmustine-induced DNA repair. This drug combination significantly impaired the sphere-forming ability of GSCs in vitro and tumor formation in vivo, leading to increase in the overall survival of mice bearing orthotopic inoculation of GSCs. Further mechanistic study showed that 3-BrOP and carmustine inhibited glyceraldehyde-3-phosphate dehydrogenase and caused a severe energy crisis in GSCs. Our study suggests that GSCs are highly glycolytic and that certain drug combination strategies can be used to effectively overcome their drug resistance based on their metabolic properties.
Characteristics of the compact plasma device AIT‐PID with multicusp magnetic confinement
Authors: Takamura Shuichi
Published: November 2012

A unique plasma‐generation device called the “Aichi Institute of Technology‐Plasma Irradiation Device” has been developed for plasma–wall interaction (PWI) studies toward realization of a fusion reactor. It has power‐saving characteristics as well as compactness due to the employment of a multicusp magnetic field configuration instead of a strong axial magnetic field. Helium as well as argon plasmas are generated, showing an outstanding property of production of the hot‐electron component which can be controlled by changing the working gas pressure. Utilizing such outstanding properties, some typical studies on PWI are introduced. An azimuthally asymmetric confinement depending on the direction of magnetic field lines, particularly for energetic electrons, has been found. Some discussions on the physical mechanisms are given. IEEJ Trans 2011 DOI: 10.1002/tee.21801
Maximization of distributed generation by considering system operating limits and protection reach reduction as constraints
Authors: Van Tu Dao , Chaitusaney Surachai , Yokoyama Akihiko
Published: November 2012

Increased distributed generation (DG) in systems always brings about the impacts on maintaining the operation of protection systems. This paper concentrates on the impact on the protection reach reduction and proposes a solution to eliminate this impact by using a suitable DG transformer in parallel with a grounding reactance at the neutral point of the transformer's winding. Based on this, a Tabu search algorithm is proposed to maximize DG when the system operating limits and the protection reach reduction are considered as constraints. In order to illustrate the effectiveness of this algorithm, a case study is performed through an IEEE 34 Node Test Feeder. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Short‐term stability in the intermediate region between quartz crystal oscillation and LC oscillation
Authors: Ruslan Ruzaini Izyan , Satoh Tomio , Akitsu Tetsuya
Published: November 2012

In a quartz crystal oscillator circuit, an LC resonance circuit was inserted that enabled major enlargement of the variable range of frequency compared with the conventional Colpitts or Pierce quartz crystal oscillator. The short‐term stability of the oscillation was measured with Allan variance in the intermediate region between the quartz resonance and LC resonance, showing higher stability compared with the common LC oscillator. The analytical result is presented showing continuous transition from the quartz resonance to the LC resonance. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Spin effects in the antler event topology at hadron colliders
Authors: Edelhäuser Lisa , Matchev Konstantin T. , Park Myeonghun
Published: November 2012

Abstract

We investigate spin correlation effects in the “antler” event topologypp→A(A*) →B1B2→ (ℓ−C1)(ℓ+C2) at the LHC. We study the shapes of several kinematic variables, including the relative pseudorapidity, relative azimuthal angle and the energies of the two leptons, as well as several mass variablesMℓℓ,Meff,$ \sqrt {{{{s}_{{\min }}}}} $,MT2,MCTandMCTx. We focus on the two kinematic extremes of$\sqrt{S}$— threshold and infinity — and derive analytical expressions for the differential distributions of several variables, most notably the cos$\theta_{{\ell -\ell +}}^{*}$variable proposed by Barr in hep-ph/0511115. For all possible spin assignments of particles A, B and C, we derive the cos$\theta_{{\ell -\ell +}}^{*}$differential distribution at threshold, including the effects of spin correlations. Our analytical results help identify the problematic cases for spin discrimination.
Long‐term Follow‐up of the “Wait and See” Approach to Localized Perinatal Adrenal Neuroblastoma
Authors: Cozzi Denis Andrew , Mele Ermelinda , Ceccanti Silvia , Natale Fabio , Clerico Anna , Schiavetti Amalia , Dominici Carlo
Published: November 2012

Background

Evidence‐based guidelines for the management of localized perinatal adrenal neuroblastoma are not yet available. We describe our preliminary experience managing this tumor with a “wait and see” policy.

Methods

A single‐center prospective study (February 2002 to December 2009) was conducted with 12 consecutive patients in whom an adrenal mass was detected antenatally or within the first 3 months of life. Diagnostic workup included the following investigations: measurement of urine catecholamine metabolites, imaging studies (ultrasonography, magnetic resonance imaging, or computed tomography), metaiodobenzylguanidine scintigraphy, and/or core needle biopsy.

Results

The male/female ratio was 1.4:1.0. Median tumor size at presentation was 29 mm (range 10–50 mm). Eight lesions were detected antenatally. Ten lesions were diagnosed as localized neuroblastoma. Of these ten lesions, four were excised because of parental preference (n = 2), tumor enlargement (n = 1) or tumor persistence (n = 1). The remaining six patients underwent watchful clinical observation, which showed progressive tumor shrinkage and complete regression within 10–39 months (median 12.5 months). The final two lesions were small predominantly cystic lesions without a clear‐cut diagnosis. They were managed noninvasively. At an overall median follow‐up of 109 months (range 30–122 months), all patients are alive and disease‐free, although one patient progressed to stage 4 disease despite early excision of the primary tumor.

Conclusions

Spontaneous regression of localized perinatal adrenal neuroblastoma occurs often, and a “wait and see” strategy seems justified in these small infants. Patients with enlarging or stable lesions that have persisted for several months may benefit from surgery, although prompt excision may not prevent tumor progression.
Isolated Avulsion Fracture of the Lesser Tuberosity of the Humerus: Case Report and Literature Review
Authors: Lik-Hang Hung , Kwong-Yin Chung , Ning Tang , Kwok-Sui Leung
Published: November 2012

Isolated avulsion fracture of the lesser tuberosity of the humerus is a rare injury. It is easily missed because the fracture is difficult to visualize in routine plain radiographs of the shoulder. This article reports a man who sustained a right shoulder injury after a fall. Physical examination found local tenderness over the anterior aspect of his right humerus. The initial plain radiographs of shoulder showed no fracture. However, the axillary view demonstrated a rare isolated avulsion fracture of the lesser tuberosity. He was treated nonoperatively with good clinical outcome.
The serum miR‐21 level serves as a predictor for the chemosensitivity of advanced pancreatic cancer, and miR‐21 expression confers chemoresistance by targeting FasL
Authors: Wang Peng , Zhuang Liping , Zhang Juan , Fan Jie , Luo Jianmin , Chen Hao , Wang Kun , Liu Luming , Chen Zhen , Meng Zhiqiang
Published: November 2012

miR‐21 expression in cancer tissue has been reported to be associated with the clinical outcome and activity of gemcitabine in pancreatic cancer. However, resection is possible in only a minority of patients due to the advanced stages often present at the time of diagnosis, and safely obtaining sufficient quantities of pancreatic tumor tissue for molecular analysis is difficult at the unresectable stages. In this study, we investigated whether the serum level of miR‐21 could be used as a predictor of chemosensitivity. We tested the levels of serum miR‐21 in a cohort of 177 cases of advanced pancreatic cancer who received gemcitabine‐based palliative chemotherapy. We found that a high level of miR‐21 in the serum was significantly correlated with a shortened time‐to‐progression (TTP) and a lower overall survival (OS). The serum miR‐21 level was an independent prognostic factor for both the TTP and the OS (HR 1.920; 95% CI, 1.274–2.903, p = 0.002 for TTP and HR 1.705; 95% CI, 1.147–2.535, p = 0.008 for OS). The results from a functional study showed that gemcitabine exposure down‐regulated miR‐21 expression and up‐regulated FasL expression. The increased FasL expression following gemcitabine treatment induced cancer cell apoptosis, whereas the ectopic expression of miR‐21 partially protected the cancer cells from gemcitabine‐induced apoptosis. Additionally, we confirmed that FasL was a direct target of miR‐21. Therefore, the serum level of miR‐21 may serve as a predictor of chemosensitivity in advanced pancreatic cancer. Additionally, we identified a new mechanism of chemoresistance mediated by the effects of miR‐21 on the FasL/Fas pathway.
The Performative Presidency
Authors: Mast Jason L.
Published: November 2012

The Performative Presidency brings together literatures describing presidential leadership strategies, public understandings of citizenship, and news production and media technologies between the presidencies of Theodore Roosevelt and Bill Clinton, and details how the relations between these spheres have changed over time. Jason L. Mast demonstrates how interactions between leaders, publics, and media are organized in a theatrical way, and argues that mass mediated plot formation and character development play an increasing role in structuring the political arena. He shows politics as a process of ongoing performances staged by motivated political actors, mediated by critics, and interpreted by audiences, in the context of a deeply rooted, widely shared system of collective representations. The interdisciplinary framework of this book brings together a semiotic theory of culture with concepts from the burgeoning field of performance studies.
Topics in Critical Point Theory
Authors: Perera Kanishka , Schechter Martin
Published: November 2012

This book introduces the reader to powerful methods of critical point theory and details successful contemporary approaches to many problems, some of which had proved resistant to attack by older methods. Topics covered include Morse theory, critical groups, the minimax principle, various notions of linking, jumping nonlinearities and the Fučík spectrum in an abstract setting, sandwich pairs and the cohomological index. Applications to semilinear elliptic boundary value problems, p-Laplacian problems and anisotropic systems are given. Written for graduate students and research scientists, the book includes numerous examples and presents more recent developments in the subject to bring the reader up to date with the latest research.
Atmospheric infrasound from nonlinear wave interactions during Hurricanes Felicia and Neki of 2009
Authors: Stopa Justin E. , Cheung Kwok Fai , Garcés Milton A. , Badger Nickles
Published: November 2012

Monitoring stations around the globe routinely detect microbarom signals with a dominant frequency of ∼0.2 Hz from regions of marine storminess. International Monitoring System (IMS) infrasound array IS59 in Kailua‐Kona, Hawaii recorded clear signals in close proximity of Hurricanes Felicia and Neki of 2009 for a first‐hand investigation of the detailed source mechanism through a hindcast analysis. A spectral wave model describes the tropical cyclone and ambient sea states through a system of two‐way nested grids with forcing from a blended data set of global, regional, and cyclonic winds. The computed wave conditions are validated with altimetry measurements and utilized in an acoustic model to estimate the intensity and spatial distribution of the microbarom source. The model results elucidate origins of infrasound signals from the tropical cyclone waves as well as their interactions with the ambient conditions consisting of swells, wind seas, and storm waves from nearby systems. The positive correlation between the IS59 observations and the theoretical microbarom estimates, and the saturation of recorded signals from high‐energy sources support the use of infrasound signals for inference of tropical cyclone waves.
Identifying the optimal spatially and temporally invariant root distribution for a semiarid environment
Authors: Sivandran Gajan , Bras Rafael L.
Published: November 2012

In semiarid regions, the rooting strategies employed by vegetation can be critical to its survival. Arid regions are characterized by high variability in the arrival of rainfall, and species found in these areas have adapted mechanisms to ensure the capture of this scarce resource. Vegetation roots have strong control over this partitioning, and assuming a static root profile, predetermine the manner in which this partitioning is undertaken.A coupled, dynamic vegetation and hydrologic model, tRIBS + VEGGIE, was used to explore the role of vertical root distribution on hydrologic fluxes. Point‐scale simulations were carried out using two spatially and temporally invariant rooting schemes: uniform: a one‐parameter model and logistic: a two‐parameter model. The simulations were forced with a stochastic climate generator calibrated to weather stations and rain gauges in the semiarid Walnut Gulch Experimental Watershed (WGEW) in Arizona. A series of simulations were undertaken exploring the parameter space of both rooting schemes and the optimal root distribution for the simulation, which was defined as the root distribution with the maximum mean transpiration over a 100‐yr period, and this was identified. This optimal root profile was determined for five generic soil textures and two plant‐functional types (PFTs) to illustrate the role of soil texture on the partitioning of moisture at the land surface. The simulation results illustrate the strong control soil texture has on the partitioning of rainfall and consequently the depth of the optimal rooting profile. High‐conductivity soils resulted in the deepest optimal rooting profile with land surface moisture fluxes dominated by transpiration. As we move toward the lower conductivity end of the soil spectrum, a shallowing of the optimal rooting profile is observed and evaporation gradually becomes the dominate flux from the land surface. This study offers a methodology through which local plant, soil, and climate can be accounted for in the parameterization of rooting profiles in semiarid regions.
Effect of ship locking on sediment oxygen uptake in impounded rivers
Authors: Lorke A. , McGinnis D. F. , Maeck A. , Fischer H.
Published: November 2012

In the majority of large river systems, flow is regulated and/or otherwise affected by operational and management activities, such as ship locking. The effect of lock operation on sediment‐water oxygen fluxes was studied within a 12.9 km long impoundment at the Saar River (Germany) using eddy‐correlation flux measurements. The continuous observations cover a time period of nearly 5 days and 39 individual locking events. Ship locking is associated with the generation of surges propagating back and forth through the impoundment which causes strong variations of near‐bed current velocity and turbulence. These wave‐induced flow variations cause variations in sediment‐water oxygen fluxes. While the mean flux during time periods without lock operation was 0.5 ± 0.1 g m−2 d−1, it increased by about a factor of 2 to 1.0 ± 0.5 g m−2 d−1within time periods with ship locking. Following the daily schedule of lock operations, fluxes are predominantly enhanced during daytime and follow a pronounced diurnal rhythm. The driving force for the increased flux is the enhancement of diffusive transport across the sediment‐water interface by bottom‐boundary layer turbulence and perhaps resuspension. Additional means by which the oxygen budget of the impoundment is affected by lock‐induced flow variations are discussed.
Smart textiles: Challenges and opportunities
Authors: Cherenack Kunigunde , van Pieterson Liesbeth
Published: November 2012

Smart textiles research represents a new model for generating creative and novel solutions for integrating electronics into unusual environments and will result in new discoveries that push the boundaries of science forward. A key driver for smart textiles research is the fact that both textile and electronics fabrication processes are capable of functionalizing large-area surfaces at very high speeds. In this article we review the history of smart textiles development, introducing the main trends and technological challenges faced in this field. Then, we identify key challenges that are the focus of ongoing research. We then proceed to discuss fundamentals of smart textiles: textile fabrication methods and textile interconnect lines, textile sensor, and output device components and integration of commercial components into textile architectures. Next we discuss representative smart textile systems and finally provide our outlook over the field and a prediction for the future.
Signature of optical absorption in highly strained and partially relaxed InP/GaAs type-II quantum well superlattice structures
Authors: Singh S. D. , Porwal S. , Sharma T. K. , Oak S. M.
Published: November 2012

Signature of optical absorption in highly strained and partially relaxed InP/GaAs type-II quantum well superlattice structures is clearly observed at room temperature. Strong coupling effects between the wavefunctions of confined carriers in the neighbouring quantum wells of InP/GaAs type-II superlattice structures are observed in electroreflectance (ER) spectra. Only ER measurements provide clear signatures of the superlattice feature for partially relaxed superlattice structures. However, both ER and photoreflectance (PR) measurements provide the signature of superlattice features for highly strained superlattice structures. A possible explanation is given in terms of the trapping of photogenerated carriers at defect/trap levels generated by the partial relaxation or due to the presence of oscillatory features in PR spectra. ER being a direct modulation technique, where one applies an external electric field to modulate the built-in electric field, is therefore preferred over PR. Increase in the surface photovoltage magnitude for energies lower than the band edge position of GaAs buffer layer confirms that the absorption takes place between the electronic minibands formed in the type-II superlattice structures.
Porosity tuning of the optical properties of mesoporous silica planar defect in macroporous silica opal
Authors: Peiris F. C. , Murphree J. D. , Rodriguez J. R. , Hatton B. D. , Kitaev V. , Ozin G. A.
Published: November 2012

Periodic mesoporous silica films were embedded between photonic crystals to form defect-based monolithic structures capable of post-growth tuning. Tetramethyl orthosilicate was infiltrated into monolithic structures in order to form silica layers in their void spaces, resulting in changes to the optical spectra. With the increase in the number of infiltration cycles, the optical signatures of the defect-based monolithic structures red-shift, caused mainly by the increase in the effective index of refraction of the entire structure. Furthermore, the red-shift of the optical signatures in monolithic structures deviates when compared to the net-effect of infiltration on stand-alone structures of periodic mesoporous silica films and photonic crystals. Simulations based on scalar wave approximation corroborate the results obtained by ellipsometry, UV-VIS spectroscopy, scanning electron microscopy, and x-ray diffraction experiments.
1,1-diamino-2,2-dinitroethylene under high pressure-temperature
Authors: Bishop Matthew M. , Chellappa Raja S. , Pravica Michael , Coe Josh , Liu Zhenxian , Dattlebaum Dana , Vohra Yogesh , Velisavljevic Nenad
Published: November 2012

The structural phase stability of 1,1-diamino-2,2-dinitroethylene (FOX-7) has been studied up to 10 GPa through isothermal compression at 100 °C and 200 °C using synchrotron mid- and far-infrared spectroscopy. During isothermal compression at 100 °C changes are observed in vibrational spectra with increase in pressure that are indicative of significant distortion to monoclinic α phase or a possible structural transformation to a high pressure α′ phase at 2.2 GPa and α″ phase at 6.1 GPa. At 200 °C, for the far- and mid-IR regimes, the similar changes were observed at 2.1 (2.0) GPa and 5.3 (5.5) GPa, respectively. The observed change is nearly isobaric, consistent with previously reported high pressure and room temperature values, up to the highest temperature of 200 °C reached in our experiments. Over the total P-T range investigated, up to ∼10 GPa and 200 °C, we observed no evidence of sample decomposition. The observed changes are partially reversible with only slight evidence of the high pressure distortion remaining upon complete decompression. Additional isobaric heating at 1.07 GPa was performed in the mid-IR regime, which clearly revealed an onset of decomposition at 360 °C. Further x-ray or neutron diffraction, which are needed to fully resolve the cause of observed changes above 2 and 5 GPa, are ongoing.
Practical aspects of single-pass scan Kelvin probe force microscopy
Authors: Li Guangyong , Mao Bin , Lan Fei , Liu Liming
Published: November 2012

The single-pass scan Kelvin probe force microscopy (KPFM) in ambient condition has a few advantages over the dual-pass lift-up scan KPFM. For example, its spatial resolution is expected to be higher; and its topographical errors caused by electrostatic forces are minimized because electrostatic forces are actively suppressed during the simultaneous topographical and KPFM measurement. Because single-pass scan KPFM in ambient condition is relatively new, it received little attention in the literature so far. In this article, we discuss several major practical aspects of single-pass scan KPFM especially in ambient condition. First, we define the resolution using a point spread function. With this definition, we analyze the relation between the resolution and the scanning parameters such as tip apex radius and tip-surface distance. We further study the accuracy of KPFM based on the point spread function. Then, we analyze the sensitivity of KPFM under different operation modes. Finally, we investigate the crosstalk between the topographical image and the surface potential image and demonstrate the practical ways to minimize the crosstalk. These discussions not only help us to understand the single-pass scan KPFM but also provide practical guidance in using single-pass scan KPFM.
A correlated-polaron electronic propagator: Open electronic dynamics beyond the Born-Oppenheimer approximation
Authors: Parkhill John A. , Markovich Thomas , Tempel David G. , Aspuru-Guzik Alan
Published: November 2012

In this work, we develop an approach to treat correlated many-electron dynamics, dressed by the presence of a finite-temperature harmonic bath. Our theory combines a small polaron transformation with the second-order time-convolutionless master equation and includes both electronic and system-bath correlations on equal footing. Our theory is based on the ab initio Hamiltonian, and is thus well-defined apart from any phenomenological choice of basis states or electronic system-bath coupling model. The equation-of-motion for the density matrix we derive includes non-Markovian and non-perturbative bath effects and can be used to simulate environmentally broadened electronic spectra and dissipative dynamics, which are subjects of recent interest. The theory also goes beyond the adiabatic Born-Oppenheimer approximation, but with computational cost scaling such as the Born-Oppenheimer approach. Example propagations with a developmental code are performed, demonstrating the treatment of electron-correlation in absorption spectra, vibronic structure, and decay in an open system. An untransformed version of the theory is also presented to treat more general baths and larger systems.
Efficient energy transfer in light-harvesting systems: Quantum-classical comparison, flux network, and robustness analysis
Authors: Wu Jianlan , Liu Fan , Ma Jian , Silbey Robert J. , Cao Jianshu
Published: November 2012

Following the calculation of optimal energy transfer in thermal environment in our first paper [J. L. Wu, F. Liu, Y. Shen, J. S. Cao, and R. J. Silbey, New J. Phys. 12, 105012 (2010)10.1088/1367-2630/12/10/105012], full quantum dynamics and leading-order “classical” hopping kinetics are compared in the seven-site Fenna-Matthews-Olson (FMO) protein complex. The difference between these two dynamic descriptions is due to higher-order quantum corrections. Two thermal bath models, classical white noise (the Haken-Strobl-Reineker (HSR) model) and quantum Debye model, are considered. In the seven-site FMO model, we observe that higher-order corrections lead to negligible changes in the trapping time or in energy transfer efficiency around the optimal and physiological conditions (2% in the HSR model and 0.1% in the quantum Debye model for the initial site at BChl 1). However, using the concept of integrated flux, we can identify significant differences in branching probabilities of the energy transfer network between hopping kinetics and quantum dynamics (26% in the HSR model and 32% in the quantum Debye model for the initial site at BChl 1). This observation indicates that the quantum coherence can significantly change the distribution of energy transfer pathways in the flux network with the efficiency nearly the same. The quantum-classical comparison of the average trapping time with the removal of the bottleneck site, BChl 4, demonstrates the robustness of the efficient energy transfer by the mechanism of multi-site quantum coherence. To reconcile with the latest eight-site FMO model which is also investigated in the third paper [J. Moix, J. L. Wu, P. F. Huo, D. F. Coker, and J. S. Cao, J. Phys. Chem. Lett. 2, 3045 (2011)10.1021/jz201259v], the quantum-classical comparison with the flux network analysis is summarized in Appendix C. The eight-site FMO model yields similar trapping time and network structure as the seven-site FMO model but leads to a more disperse distribution of energy transfer pathways.
Full counting statistics in the resonant-level model
Authors: Bernard Denis , Doyon Benjamin
Published: November 2012

We derive the large deviation function, which provides the large-time full counting statistics for the charge transfer, in the non-equilibrium steady state of the resonant-level model. The general form of this function in free fermion models, in terms of transmission coefficients, was proposed by Levitov and Lesovik in 1993 using a particular measurement set-up involving an interacting spin. It was later suggested to hold as well for a proper quantum mechanical measurement of the transferred charge. We give a precise proof of both statements in the resonant-level model. We first give a full description of the model and its steady state. That is, we explain how the decoupled system prepared with a charge differential evolves, with the impurity coupling, towards the Hershfield non-equilibrium density matrix, in the sense of averages of finitely supported operators. We describe how this holds both for the usual resonant-level model with a point-like impurity, and for a regularized model with an impurity spread on a finite region, shedding light on subtleties associated to the point-like impurity. We then prove Levitov-Lesovik formula by recasting the problem into calculating averages of finitely supported operators.
The addition of strain in uniaxially strained transistors by both SiN contact etch stop layers and recessed SiGe sources and drains
Authors: Denneulin Thibaud , Cooper David , Hartmann Jean-Michel , Rouviere Jean-Luc
Published: November 2012

SiN contact etch stop layers (CESL) and recessed SiGe sources/drains are two uniaxial strain techniques used to boost the charge carriers mobility in p-type metal oxide semiconductor field effect transistors (pMOSFETs). It has already been shown that the electrical performances of the devices can be increased by combining both of these techniques on the same transistor. However, there are few experimental investigations of their additivity from the strain point of view. Here, spatially resolved strain mapping was performed using dark-field electron holography (DFEH) on pMOSFETs transistors strained by SiN CESL and embedded SiGe sources/drains. The influence of both processes on the strain distribution has been investigated independently before the combination was tested. This study was first performed with non-silicided devices. The results indicated that in the channel region, the strain induced by the combination of both processes is equal to the sum of the individual components. Then, the same investigation was performed after Ni-silicidation of the devices. It was found that in spite of a slight reduction of the strain due to the silicidation, the strain additivity is approximately preserved. Finally, it was also shown that DFEH can be a useful technique to characterize the strain field around dislocations.
Positive effective Q12 electrostrictive coefficient in perovskites
Authors: Kvasov Alexander , Tagantsev Alexander K.
Published: November 2012

It is demonstrated that for classical perovskites, such as BaTiO3, SrTiO3, and PbTiO3, electrostrictive strain induced by an electric field may not obey traditionally considered “extension along the field and contraction perpendicular to it” behavior if the applied electric field is directed obliquely to the cubic crystallographic directions. A remarkable behavior is predicted for bars of BaTiO3, SrTiO3, and PbTiO3 cut along the [111] crystallographic cubic direction. In this case, in the paraelectric phase in an electric field parallel to the bar, some expansion along all its three dimensions is expected. The situation with the [110] cut is also unusual; the electrostrictive effect in a field along the bar will result in a contraction in one transversal direction and an expansion in the other. In terms of the effective “polarization-strain” electrostrictive coefficients of the sample, this means a positive transversal electrostriction coefficient for some sample orientations.
Prediction of organic molecular crystal geometries from MP2-level fragment quantum mechanical/molecular mechanical calculations
Authors: Nanda Kaushik D. , Beran Gregory J. O.
Published: November 2012

The fragment-based hybrid many-body interaction (HMBI) model provides a computationally affordable means of applying electronic structure wavefunction methods to molecular crystals. It combines a quantum mechanical treatment of individual molecules in the unit cell and their short-range pairwise interactions with a polarizable molecular mechanics force-field treatment of long-range and many-body interactions. Here, we report the implementation of analytic nuclear gradients for the periodic model to enable full relaxation of both the atomic positions and crystal lattice parameters. Using a set of five, chemically diverse molecular crystals, we compare the quality of the HMBI MP2/aug-cc-pVDZ-level structures with those obtained from dispersion-corrected periodic density functional theory, B3LYP-D*, and from the Amoeba polarizable force field. The MP2-level structures largely agree with the experimental lattice parameters to within 2%, and the root-mean-square deviations in the atomic coordinates are less than 0.2 Å. These MP2 structures are almost as good as those predicted from periodic B3LYP-D*/TZP and are significantly better than those obtained with B3LYP-D*/6-31G(d,p) or with the Amoeba force field.
Development and application of a particle-particle particle-mesh Ewald method for dispersion interactions
Authors: Isele-Holder Rolf E. , Mitchell Wayne , Ismail Ahmed E.
Published: November 2012

For inhomogeneous systems with interfaces, the inclusion of long-range dispersion interactions is necessary to achieve consistency between molecular simulation calculations and experimental results. For accurate and efficient incorporation of these contributions, we have implemented a particle-particle particle-mesh Ewald solver for dispersion (r−6) interactions into the LAMMPSmolecular dynamics package. We demonstrate that the solver's \documentclass[12pt]{minimal}\begin{document}$\mathcal {O}(N\log N)$\end{document}O(NlogN) scaling behavior allows its application to large-scale simulations. We carefully determine a set of parameters for the solver that provides accurate results and efficient computation. We perform a series of simulations with Lennard-Jones particles, SPC/E water, and hexane to show that with our choice of parameters the dependence of physical results on the chosen cutoff radius is removed. Physical results and computation time of these simulations are compared to results obtained using either a plain cutoff or a traditional Ewald sum for dispersion.