cssi/SciSciGPT-SciSciNet huggingface dataset:
Nanometer-Scale Corrosion of Copper in De-Aerated Deionized Water

The need for increasingly more-functional electronics and the industry’s ability to fabricate high density integrated circuits have led to an ever-increasing generation of waste heat in advanced electronics systems. The increases in heat generation has often been handled by improvements in materials or components configuration. However, it is now generally acknowledged that the cooling requirements for advanced electronics exceed the heat-removal capability of conventional cooling techniques. Liquid-based cooling 1-7 may remedy thermal management issues that have plagued development and deployment of enhanced electronic systems. Due to its exceptional heat transfer characteristics, particularly in the phase change process, water is considered to be a suitable cooling fluid, so long as issues related to its electrical properties can be addressed. Numerous studies have been conducted to develop high performance water heat sinks. 8-13 These studies often utilize micro- or nanostructures to enhance heat transfer at the solid-liquid interface. Traditionally, copper has been the material of choice in water heat exchangers, and, as it is generally understood that copper does not corrode in deaerated deionized water, copper micro/nanostructures are implemented to benefit from the associated enhanced heat transfer characteristics. The performance of micro/nanoscale copper structures has, however, been observed to degrade with time. Ju et al. 14 reported that corrosion in copper microfluidic channels used in a two-phase cooling system caused performance degradation. Since the cooling performance is intricately related to functionality of the liquid-vapor interface and fluid flow through a structure, 15 even small rates of corrosion can impair performance of a micro/nanostructured interface. Thus, an ability to predict and mitigate copper corrosion is needed. The corrosion of copper in aerated media is relatively well understood. In acidic chloride solutions, for example, the corrosion of copper takes place by a mechanism that involves formation of CuCl −1 from a CuCl intermediate. 16 The reaction process is reported to be diffusion controlled with no evidence of a protective oxide layer. 17 This mechanism has been presented as valid for temperatures as high as 165 ◦ C. 18 A similar body of work does not exist for corrosion of copper micro/nanoscale structures in heat exchangers, though this area may be closely related to the body of work associated with plans for encasing nuclear waste in copper cladding. The standard equilibrium potential for the copper dissolution reaction has a value of 0.337 V with reference to the hydrogen reaction; 19 therefore, copper is commonly believed to be immune to corrosion in neutral deionized deaerated
Fast lossy Internet image transmission

Images are usually transmitted across the Internet using a lossless protocol such as TCP/IP. Lossless protocols require retransmission of lost packets, which substantially increases transmission time. We introduce a fast lossy Internet image transmission scheme (FLIIT) for compressed images which eliminates retransmission delays by strategically shielding important portions of the image with redundancy bits. We describe a joint source and channel coding algorithm for images which minimizes the expected distortion of transmitted images. The algorithm efficiently allocates quantizer resolution bits and redundancy bits to control quantization errors and expected packet transmission losses. We describe an implementation of this algorithm and compare its performance on the Internet to lossless TCP/IP transmission of the same images. In our experiments, the FLIIT scheme transmitted images five times faster than TCP/IP during the day, with resulting images of equivalent quality.
Shortness of breath as a predictor of depressive symptoms in a community sample of older adults.

Objectives Physical symptoms are known to be associated with late life depression both cross-sectionally and over time. We attempted to determine if self-reported shortness of breath (SoB) is associated with depressive symptoms at long-term (3-year) follow-up in a community sample of older (65+) adults. Methods A sample of 2926 elderly subjects from the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE) were evaluated at baseline and at 3-year follow-up. Depressive symptoms were assessed by a modified version of the Center for Epidemiologic Studies—Depression Scale (CES-D) and SoB was assessed by a three-item scale administered at baseline. The analyses were controlled for factors known to be associated with depressive symptoms and SoB. Both bivariate and multivariate analyses were performed. Results Eighty-three percent of subjects who experienced SoB survived for three years. Within the analysis sample of those participating at follow-up, 36 percent experienced SoB at baseline. In biavriate analyses, SoB, older age, female sex, history of a heart attack, higher body mass index (BMI), depressive symptoms at baseline, cognitive impairment, and functional impairment were associated with follow-up depressive symptoms. When controlled variables were included in a linear regression model, SoB was a significant predictor of depressive symptoms at follow-up (p < 0.0001) as well as baseline depressive symptoms, sex, BMI, and functional status. No two-way interaction terms with SoB were significant. Conclusions SoB is a significant predictor of depressive symptoms at 3-year follow-up. Given that SoB is a symptom that is responsive to therapeutic intervention, active intervention to relieve the symptom when identified could reduce the incidence of depressive symptoms. Copyright © 2010 John Wiley & Sons, Ltd.
Transformer winding loss caused by skin and proximity effects including harmonics in pulse-width modulated DC¿DC flyback converters for the continuous conduction mode

High-frequency (HF) transformers used in pulse-width-modulated power converters conduct periodic non-sinusoidal HF currents, which give rise to additional winding losses caused by harmonics. This study presents expressions for winding power losses in a two-winding transformer with periodic non-sinusoidal primary and secondary current waveforms for flyback converters operating in the continuous conduction mode (CCM). Dowell's equation, which takes into account both the skin and proximity effects, is used to determine the primary and secondary winding resistances as functions of frequency. Fourier series of the primary and secondary current waveforms and the winding resistances are used to determine the winding power losses at harmonic frequencies. The harmonic primary and secondary winding loss factors FRph and FRsh are introduced for CCM operation. The theory is illustrated by performance evaluation of the transformer in a flyback converter in CCM over the entire range of converter operation. Power losses in the primary and secondary transformer windings are illustrated as functions of the output power and the DC input voltage.
Gaussian fluctuation in random matrices.

Let $N(L)$ be the number of eigenvalues, in an interval of length $L$, of a matrix chosen at random from the Gaussian orthogonal, unitary, or symplectic ensembles of $N$ by $N$ matrices, in the limit $N\ensuremath{\rightarrow}\ensuremath{\infty}$. We prove that $[N(L)\ensuremath{-}〈N(L)〉]/\sqrt{\mathrm{ln}L}$ has a Gaussian distribution when $L\ensuremath{\rightarrow}\ensuremath{\infty}$. This theorem, which requires control of all the higher moments of the distribution, elucidates numerical and exact results on chaotic quantum systems and on the statistics of zeros of the Riemann zeta function.
Assessment of warnings based on an ergonomic accident sequence model

Abstract The contribution of effective warnings to accident prevention has become a matter of high concern in the design, manufacture, sales, and use of products, and to the courts that are called upon to resolve disputes between these parties. Although there are many materials available in the Ergonomics/Human Factors literature that address the characteristics of warnings, this paper summarizes these rules and principles into a structure which is easily understood and recalled through reference to an ergonomic based accident sequence model. The accident sequence model describes four basic ergonomic oriented stages from human perception to action, along with the relevant warning principles associated with each stage. Specifically, the Perception stage involves warnings that are Noticeable and Readable; the hazard Cognition stage requires a warning to be Comprehensible and Practical; for the Decision stage a warning must be Motivational and Justifiable; in the Avoidance stage the warning must describe an action or inaction that is Possible. A reasonable way of estimating warning effectiveness through the use of systematic analysis is described.
On the spectral radius of the product of matrix exponentials

Abstract Cohen, Friedland, Kato, and Kelly conjectured that F ( t )≡log r ( e At e Bt ) is convex for real t when A is nonnegative and B is diagonal; here r is the spectral radius. While the conjecture is correct for dimension n =1 or 2, it is shown here to be false for n ⩾3. Similarly t → logTrace( e At e Bt ) k need not be convex when n ⩾3.
Assessing the trypanocidal potential of natural and semi-synthetic diketopiperazines from two deep water marine-derived fungi

Human African trypanosomiasis (HAT, commonly known as African sleeping sickness) is categorized as a neglected disease, as it afflicts >50,000 people annually in sub-saharan Africa, and there are few formal programs in the world focused on drug discovery approaches for this disease. In this study, we examined the crude extracts of two fungal strains (Aspergillus fumigatus and Nectria inventa) isolated from deep water sediment which provided >99% growth inhibition at 1microg/mL of Trypanosoma brucei, the causative parasite of HAT. A collection of fifteen natural products was supplemented with six semi-synthetic derivatives and one commercially available compound. Twelve of the compounds, each containing a diketopiperazine core, showed excellent activity against T. brucei (IC(50)=0.002-40microM), with selectivity over mammalian cells as great as 20-fold. The trypanocidal diketopiperazines were also tested against two cysteine protease targets Rhodesain and TbCatB, where five compounds showed inhibition activity at concentrations less than 20microM. A preliminary activity pattern is described and analyzed.
A model of cluster searching based on classification

Abstract The use of document clusters has been suggested as an efficient file organization for a document retrieval system. It is possible that by using this information about the relationships between documents that the effectiveness of the system (i.e. its ability to distinguish relevant from non-relevant documents) may also be improved. In this paper a probabilistic model of cluster searching based on query classification is described. This model is tested with retrieval experiments which indicate that it can be more effective than heuristic cluster searches and cluster searches based on other models. It can also be more effective than a full search in which every document is compared to the query. The efficiency aspects of the implementation of the model are discussed.
Erythromycin enhances delayed gastric emptying in dogs after Roux-Y antrectomy

Delayed gastric emptying occurs in up to 50% of patients after truncal vagotomy and Roux-Y antrectomy and is often resistant to nonsurgical therapy. This study evaluates the effect of erythromycin, metoclopramide, and motilin on delayed gastric emptying in four dogs after Roux-Y antrectomy. Solid food gastric emptying was measured using a radionuclide technique. Study groups were: (1) saline control; (2) erythromycin 1 mg/kg intravenously over 1 hour; (3) erythromycin 3 mg/kg by mouth 45 minutes prior to feeding; (4) metoclopramide 0.6 mg/kg intravenously over 1 hour; and (5) motilin 500 ng/kg intravenously over 1 hour. After Roux-Y antrectomy, saline control dogs had 73% +/- 5% (SEM) gastric retention at 2 hours. After intravenous and oral erythromycin, gastric emptying improved at 2 hours to 27% +/- 6% and 39% +/- 5% (p less than 0.01 compared with control). Erythromycin intravenously and by mouth improved gastric emptying compared with metoclopramide (64% +/- 8%, p less than 0.05). Motilin enhanced gastric emptying to a similar degree as erythromycin, with a 2-hour gastric retention of 37% +/- 4% (NS). Erythromycin improved gastric emptying in dogs with severe Roux-Y gastroparesis and may have clinical application.
A packaged workshop for teaching critical reading of the medical literature.

The purpose, goals and format of a series of teaching seminars for critical analysis of the medical literature is described. Developed as part of a faculty development program, the packaged course of instruction has been found to be a useful and popular method of teaching research methodology and critical reading skills to residents, medical students and primary care physicians.
Dinitrogen and acetylide complexes of low-valent chromium.

Reaction of trans-(dmpe)2CrCl2 (dmpe = 1,2-bis(dimethylphosphino)ethane) with one equivalent of LiCCSiMe3 and one equivalent of nBuLi in THF under a dinitrogen atmosphere affords dark orange trans,trans-[(Me3SiCC)(dmpe)2Cr]2(µ-N2)·hexane (1). Under similar conditions but in the absence of acteylide ligand, the reaction of trans-(dmpe)2CrCl2 with 2 equivalents of nBuLi yields the previously characterized complex trans-(dmpe)2Cr(N2)2 (2), while the reaction of trans-(dmpe)2CrCl2 with 2 equivalents of LiCCSiMe3 in THF yields trans-(dmpe)2Cr(CCSiMe3)2 (3). Compound 3 can also be synthesized by irradiating a mixture of trans-(dmpe)2CrMe2 and HCCSiMe3 or by reduction of HCCSiMe3 with compound 2. The magnetic properties, electrochemistry, and crystal structure of trans,trans-[(Me3SiCC)(dmpe)2Cr]2(µ-N2) are consistent with the complex containing two CrI ions bridged by a neutral N2 moiety, with a 1.178(10) A N≡N bond distance. For complex 1 redox processes centered at E1/2 = –1.69 V (ΔEp = 185 mV) and –1.43 V (ΔE...
The Maine coastal current: spring climatological circulation.

Abstract Computational results are presented for the climatological circulation in the Gulf of Maine, with special emphasis on its coastal current in the periods March-April and May-June. The simulations use a 3-D prognostic Finite Element model. The computational domain includes the entire Gulf plus adjacent waters, with a higher resolution coastal domain nested within. A series of six bimonthly Gulf-wide simulations establishes the spring conditions within the annual climatological cycle. The distinctive Gulf of Maine cyclonic circulation is persistent, with significant bimonthly modulation of key Maine coastal current features. In all cases there is a significant barotropic pressure variation of order 5 cm along the margin of the coastal current, accompanying detailed, variable interactions between it and the interior Gulf. In the spring periods of emphasis, a well-developed coastal current is present. Numerical drifters generally confirm the existence of branch points south of Penobscot Bay, east of Cape Ann, and at Great South Channel. Important differences between the March-April and May-June circulation are apparent. In particular, both the offshore transport at the Penobscot branch point and the along-shore transport at Cape Ann are strong, dominant features in March-April; both are weak in May-June. The more highly resolved, nested calculations replicate the general structure of the Gulf-wide circulation provided the correct boundary conditions are applied, confirming the pervasive dynamical influence of the Gulf-scale circulation on the coastal current. The nested calculations also expose finer structure due to river sources, heat flux, and topographic refinement. The separate influences of local (tidal rectification, local wind, local baroclinicity, river discharges) and remote (Gulf-scale) forcing are examined. Tidal rectification in the Eastern Gulf and wind-driven return flow near-shore are both important contributors to the details of the coastal current. Local baroclinicity is critical and must be in balance with the offshore pressure conditions; otherwise unrealistic exchanges with the Gulf occur. An approximate division of local and remote dynamical regimes lies near the 100-m isobath. Implications are drawn for future modeling studies.
Mice (Mus musculus) reared with rat aunts: the role of rat-mouse contact in mediating behavioural and physiological changes in the mouse.

Abstract Prior research has found that mice reared and nursed by a lactating rat mother or reared in the presence of a non-lactating adult rat (an ‘aunt’) gave a significantly smaller adrenocortical response to a novel stimulus than did control mice. Although the aunt studies eliminated the rat mother's milk as the critical variable, the experimental effect was not as profound as that originally observed using rat mothers. This may be because the rat aunt did not interact with the mice as much as the rat mother. In the first experiment we maximized the extent of the ratmouse behavioural interaction by using as an aunt a rat who had just given birth but was unable to nurse because her nipples had been previously removed (thelectomy). As hypothessized, the experimental effect was greater than previously obtained using other aunt preparations and approximated the effect obtained using rat mothers. There was no difference in body weight, but mice reared with aunts had a higher mortality rate between birth and weaning as compared to controls. In the second study experimental mice were reared by their natural mothers in the presence of a thelectomized rat (control aunt) or a thelectomized rat which had had immediate parturitional experience (post partum aunt), while control mice were reared by their natural mothers. Ratings of the maternal behaviour of rat aunts confirmed the a priori assumption that post partum aunts would be more maternal toward the mouse young than would control aunts. Mice reared with post partum aunts were found to be less active in the open field and gave a lesser adrenal corticosterone response to a novel stimulus as compared to mice reared with control aunts or control mice. In addition, within the post partum aunt group a significant correlation of −0·61 was obtained between maternal ratings and the adrenal corticosterone response of the mice. Further, the corticosterone response was positively correlated with openfield activity. The relevance of this latter finding to the interpretation of mouse open-field activity is discussed.
In vivo validation of a novel intracranial hemorrhage detector using microwaves

A novel method for identifying and localizing brain hemorrhage is presented. This method uses electromagnetic waves in the microwave and RF region and a modified algorithm previously used for the estimation of the angle of arrival of radar signals. Results are presented applying this device for detecting epidural and intracerebroventricular hemorrhages in anesthetized pig.
Maternal arrhythmia management during pregnancy in patients with structural heart disease

Abstract Arrhythmia is a common management challenge in patients with structural heart disease. During pregnancy, the severity of arrhythmia frequently worsens, sometimes irreversibly. At the same time, therapeutic options are constrained by potential teratogenicity from anti-arrhythmic medications and the risk of radiation from electrophysiological procedures. A paucity of data on the use of anti-arrhythmic medications in pregnancy has resulted in a preference for the use of β-blockers, digoxin and flecainide based on relatively successful experiences in treating maternal hypertension and fetal supraventricular tachycardia. Due to the lack of data on the safety profile of these and other agents, particularly in the first trimester, anti-arrhythmic agents should be avoided during the first trimester, whenever feasible. If radiofrequency ablation or pacemaker/defibrillator implantation is indicated, it should be performed before planned pregnancy to avoid radiation exposure to the fetus and to facilitate maternal arrhythmia management during pregnancy. DC cardioversion or atrial overdrive pacing via a permanent pacemaker or transesophageal pacing can be used to treat dysrhythmias while avoiding the side effects of anti-arrhythmic agents on the fetus. This article reviews physiological, pharmacological, electrophysiological, hemodynamic and practical considerations in the planning and management of pregnancy in the patient with congenital heart disease at risk for arrhythmia.
Merged Dictionary Code Compression for FPGA Implementation of Custom Microcoded PEs

Horizontal Microcoded Architecture (HMA) is a paradigm for designing programmable high-performance processing elements (PEs). However, it suffers from large code size, which can be addressed by compression. In this article, we study the code size of one of the new HMA-based technologies called No-Instruction-Set Computer (NISC). We show that NISC code size can be several times larger than a typical RISC processor, and we propose several low-overhead dictionary-based code compression techniques to reduce its code size. Our compression algorithm leverages the knowledge of “don't care” values in the control words and can reduce the code size by 3.3 times, on average. Despite such good results, as shown in this article, these compression techniques lead to poor FPGA implementations because they require many on-chip RAMs. To address this issue, we introduce an FPGA-aware dictionary-based technique that uses the dual-port feature of on-chip RAMs to reduce the number of utilized block RAMs by half. Additionally, we propose cascading two-levels of dictionaries for code size and block RAM reduction of large programs. For an MP3 application, a merged, cascaded, three-dictionary implementation reduces the number of utilized block RAMs by 4.3 times (76%) compared to a NISC without compression. This corresponds to 20% additional savings over the best single level dictionary-based compression.
A simpler tool for estimation of HIV incidence from cross-sectional, age-specific prevalence data

Background HIV incidence estimates are crucial in understanding and predicting the HIV/AIDS epidemic and identifying sub-populations and regions most at risk for the epidemic. However, incidence estimation is a challenge due to the nature of the disease and type of data available. This paper aims to present a simple and creative HIV incidence estimation method for resource constrained settings with scarce data. Methods The authors developed a simple user-friendly non-iterative spreadsheet estimation method, which can produce incidence estimates by age group using observed cross-sectional, age-specific HIV prevalence. Data from two prospective FHI microbicide Phase III clinical trials in Nigeria were used to validate the spreadsheet method. Since both the clinical trials involved condom use promotion to reduce HIV risk, the authors also used the AVERT software to estimate the extent of incidence reduction due to the intervention. Results The spreadsheet incidence estimates after accounting for AVERT adjusted reductions, for age groups 18–20, 21–25 and 26–30 were: 1.69%, 0.96% and 1.12% in the SAVVY trial, and 2.11%, 1.47% and 1.28% in the CS trial respectively. The corresponding actual observed incidence rates were 1.62%, 2.39%, and 1.13% in the SAVVY trial and 1.93%, 1.78% and 1.40% in the CS trial. Conclusion Comparisons of the spreadsheet-estimated incidence with the actual incidence from the clinical trials demonstrated that the method is reasonably accurate in its estimation. Because of the method9s limitations it should not be used to evaluate HIV/AIDS prevention interventions or without understanding the direction of the bias in the case of an evolving HIV epidemic.
The role of the bulk spin-dependent scattering on the origin of the enhanced magnetoresistance in magnetic multilayers

Abstract A detailed analysis of the current density distribution along the perpendicular direction of a spin-valve-like structure is presented. It is shown that, even when only bulk spin-dependent scattering is considered, the carriers responsible for the enhanced magnetoresistance in these systems are flowing in a narrow strip of the ferromagnetic layer close to the ferromagnetic/nonmagnetic interface. A modification of the bulk transport properties of this region affects drastically the giant magnetoresistance (GMR) of the overall structure.
Human Perceptions of Animals and Animal Awareness: The Cultural Dimension

Culture is generally a powerful determinant of human perceptions of animals and the treatment animals receive in a given society. For example, Plains Indians’ views of the status of animals—their capacities, their awareness, and their place in the world relative to mankind—differ radically from those characteristic of Western thought. Many of the contemporary Crow Indians, a group of native Americans among which I have recently carried out anthropological field research, continue to look upon their horses according to traditional tribal belief. Their particular attitude toward horses conflicts with that of the dominant white society with which the Indians and their horses must interact. Mutual hostility results from a lack of understanding between members of the two cultures who, though living in proximity, remain worlds apart in ethos. Two other examples from ethnographic literature involving the habitual treatment of mules in a community of farmers and of sled dogs by a group of Eskimos also highlight the importance of cultural attitudes in affecting interactions with animals in those societies. It is vital to strive to understand the many complex factors which determine views toward animals, including their capacities for awareness, in alien cultures whose value-systems may be foreign to our own.
Obesity as a Prospective Predictor of Depression in Adolescent Females

Objective: Both obesity and depression are prominent during adolescence, and it is possible that obesity is a trigger for adolescent depression. The purpose of this paper is to evaluate whether overweight or obese status contributes to the development of depression in adolescent girls. Design: Participants were 496 adolescent girls who completed interview based measures of depression and had their height and weight measured at four yearly assessments. Repeated measures logistic regressions with generalized estimating equations were used to evaluate whether overweight or obese status were associated with major depression or an increase in depressive symptoms the following year. Main Outcome Measures: Major depression and depressive symptoms were evaluating using a modified version of the K-SADS interview. Overweight and obese status was determined by using standardized protocols to measure height and weight. Results: Results showed that obese status, not overweight status, was associated with future depressive symptoms, but not major depression. This study demonstrated that obesity is a risk factor for depressive symptoms, but not for clinical depression. Conclusions: As depressive symptoms are considered along the spectrum of depression with clinical depression at the high end, these results suggest that weight status could be considered a factor along the pathway of development of depression in some adolescent females.
Fast Elastic Peak Detection for Mass Spectrometry Data Mining

We study a data mining problem concerning the elastic peak detection in 2D liquid chromatography-mass spectrometry (LC-MS) data. These data can be modeled as time series, in which the X-axis represents time points and the Y-axis represents intensity values. A peak occurs in a set of 2D LC-MS data when the sum of the intensity values in a sliding time window exceeds a user-determined threshold. The elastic peak detection problem is to locate all peaks across multiple window sizes of interest in the data set. We propose a new data structure, called a Shifted Aggregation Tree or AggTree for short, and use the data structure to find the different peaks. Our method, called PeakID, solves the elastic peak detection problem in 2D LC-MS data yielding neither false positives nor false negatives. The method works by first constructing an AggTree in a bottom-up manner from the given data set, and then searching the AggTree for the peaks in a top-down manner. We describe a state-space algorithm for finding the topology and structure of an efficient AggTree to be used by PeakID. Our experimental results demonstrate the superiority of the proposed method over other methods on both synthetic and real-world data.
Contribution to the development of thermal stabilization system for vinylidene chloride co‐polymers

Selected compounds of phosphorus and tin improve the thermal stability of vinylidene chloride co-polymers. Although offering superior intermediate color stability, incorporation of polyols will result in erratic processing of the PVdC. Combinations rather than individual compounds appear to stabilize PVdC more effectively and an explanation of the stabilization mechanism is attempted for some compounds.
VHDL simulation and modeling of an all-digital RF transmitter

We describe a simulation technique that uses an event-driven VHDL simulator to model an RF wireless transmitter. The technique is well suited to investigate complex interactions in large SoC systems, where traditional RF and analog simulation tools do not work effectively. The oscillator phase noise characteristics are described using time-domain equations. The flip-flop metastability effects on the system performance are also modeled. The VHDL simulation environment was selected for its high simulation speed, the direct correlation between the simulated and built circuits and its ability to model mixed-signal systems of high complexity. The presented simulation technique has been successfully applied and validated in a single-chip GSM/EDGE transceiver IC fabricated in a digital 90 nm process.
Monte Carlo modeling of X-valley leakage in quantum cascade lasers

This paper presents the first comprehensive Monte Carlo simulation of GaAs/AlGaAs quantum cascade lasers (QCLs) that takes both Γ- and X-valley transport into account and investigates the effect of X-valley leakage on the QCL performance. Excellent agreement with experimental data is obtained for the GaAs/Al0.45Ga0.55As QCL at cryogenic and room temperatures. The model reveals two carrier-loss mechanisms into the X valley: coupling of the Γ continuum-like states with the X states in the same stage, and coupling between the Γ localized states in the simulated stage with the X states in the next stage. Simulation results demonstrate that the 45% Al QCL has small X-valley leakage at both 77 K and 300 K, due to the very good confinement of the Γ states, stemming from the high Al content.
Decoding Near-Threshold Perception of Fear from Distributed Single-Trial Brain Activation

Instead of contrasting functional magnetic resonance imaging (fMRI) signals associated with 2 conditions, as customarily done in neuroimaging, we reversed the direction of analysis and probed whether brain signals could be used to ‘‘predict’’ perceptual states. We probed the neural correlates of perceptual decisions by ‘‘decoding’’ brain states during near-threshold fear detection. Decoding was attempted by using support vector machines and other related techniques. Although previous decoding studies have employed relatively ‘‘blocked’’ data, our objective was to probe how the ‘‘moment-to-moment’’ fluctuation in fMRI signals across a population of voxels reflected the participant’s perceptual decision. Accuracy increased from when 1 region was considered (~64%) to when 10 regions were used (~78%). When the best classifications per subject were averaged, accuracy levels ranged between 74% and 86% correct. An information theoretic analysis revealed that the information carried by pairs of regions reliably exceeded the sum of the information carried by individual regions, suggesting that information was combined ‘‘synergistically’’ across regions. Our results indicate that the representation of behavioral choice is ‘‘distributed’’ across several brain regions. Such distributed encoding may help prepare the organism to appropriately handle emotional stimuli and regulate the associated emotional response upon the conscious decision that a fearful face is present. In addition, the results show that challenging brain states can be decoded with high accuracy even when ‘‘single-trial’’ data are employed and suggest that multivariate analysis strategies have considerable potential in helping to elucidate the neural correlates of visual awareness and the encoding of perceptual decisions.
KCC2 expression supersedes NKCC1 in mature fiber cells in mouse and rabbit lenses.

Purpose Na-K-Cl cotransporter 1 (NKCC1) and K-Cl cotransporter 2 (KCC2) have fundamental roles in neuron differentiation that are integrated with gamma-aminobutyric acid (GABA) and glutamate receptors, GABA synthesized by GAD25/65/67 encoded by GAD1/GAD2 genes, and GABA transporters (GATs). Cells in the eye lens express at least 13 GABA receptor subunits, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl D-aspartate (NMDA) glutamate receptors, GAD1/GAD2, GAT1–4 and vGAT, and NKCC1. NKCC1:KCC2 ratios determine the switch in GABA actions from trophic/growth promoting early in development to their classic inhibitory roles in adult neurons. Lens epithelial cells cover the anterior surface and differentiate to elongated fiber cells in the lens interior with comparable morphology and sub-cellular structures as neurons. NKCC1 is expressed before KCC2 in neuron development and increases cell chloride, which stimulates differentiation and process formation. Subsequently, KCC2 increases and extrudes cell chloride linked with maturation. KCC2 has an additional structural moonlighting role interacting with F-actin scaffolding in dendritic spine morphogenesis. We examined KCC2 versus NKCC1 spatial expression in relation to fiber cell developmental status within the lens.
Contrasting Tactics in Motor Control by Vertebrates and Arthropods

Vertebrates and arthropods share the common problem of controlling a rigid, articulated skeleton using neurally-controlled, striated muscle. Since this condition has arisen independently in the two groups, there is no reason to assume, a priori, that the control mechanisms used by the two groups will be the same. Indeed, there appear to be fundamental differences in the tactics used by the two groups. Insects and crustaceans use small numbers of heterogeneous motoneurons, while vertebrates (mammals especially) use many, more homogeneous, motor axons. In particular, arthropods make extensive use of peripheral neuromodulation to alter the properties of both neuromuscular junctions and muscle fibers. There has been little consideration of the functional consequences of these differences. I suggest that, faced with a size constraint on the number of motor units available, arthropods use peripheral modulation of muscle properties to achieve the flexibility and dynamic range that vertebrates achieve through recruitment of motor units.
Kinesin-13 Regulates Flagellar, Interphase, and Mitotic Microtubule Dynamics in Giardia intestinalis

Microtubule depolymerization dynamics in the spindle are regulated by kinesin-13, a nonprocessive kinesin motor protein that depolymerizes microtubules at the plus and minus ends. Here we show that a single kinesin-13 homolog regulates flagellar length dynamics, as well as other interphase and mitotic dynamics in Giardia intestinalis, a widespread parasitic diplomonad protist. Both green fluorescent protein-tagged kinesin-13 and EB1 (a plus-end tracking protein) localize to the plus ends of mitotic and interphase microtubules, including a novel localization to the eight flagellar tips, cytoplasmic anterior axonemes, and the median body. The ectopic expression of a kinesin-13 (S280N) rigor mutant construct caused significant elongation of the eight flagella with significant decreases in the median body volume and resulted in mitotic defects. Notably, drugs that disrupt normal interphase and mitotic microtubule dynamics also affected flagellar length in Giardia. Our study extends recent work on interphase and mitotic kinesin-13 functioning in metazoans to include a role in regulating flagellar length dynamics. We suggest that kinesin-13 universally regulates both mitotic and interphase microtubule dynamics in diverse microbial eukaryotes and propose that axonemal microtubules are subject to the same regulation of microtubule dynamics as other dynamic microtubule arrays. Finally, the present study represents the first use of a dominant-negative strategy to disrupt normal protein function in Giardia and provides important insights into giardial microtubule dynamics with relevance to the development of antigiardial compounds that target critical functions of kinesins in the giardial life cycle.
Polyacrylamide gel electrophoresis of rat brain acetylcholinesterase: isoenzyme changes following parathion poisoning.

— Brain acetylcholinesterase (EC 3. 1. 1. 7) isoenzymes of 15- and 30-day-old rats were found to be inhibited by 2.5 mg/kg and 1.25 mg/kg dosage levels of intraperitoneally administered parathion (E-605; O, O-diethyl-p-nitrophenyl phosphorothionate). With 2.5 mg/kg dose level, the response of isoenzymes in 15- and 30-day-old rats was similar. At both ages, there was no significant sex difference in the degree of depression of the isoenzymes. There were no significant regional differences in the degree of inhibition of acetylcholinesterase isoenzymes in the rat brain. At 1.25 mg/kg dosage level, a differential isoenzyme inhibition was evident, with the major isoenzyme (isoenzyme 3) exhibiting the greatest sensitivity to the inhibitor in all brain areas examined. The course of isoenzyme depression and recovery following the administration of parathion differed in brain, serum and skeletal muscle. Whereas brain isoenzymes exhibited most marked inhibition at 2 h after injection, inhibition of serum and skeletal muscle isoenzymes was more prolonged. At 4 h after injection, these isoenzymes were still inhibited while brain isoenzymes had recovered to a substantial degree. Twenty four h following the injection of parathion, when brain and serum acetylcholinesterase isoenzymes had returned to control activity levels, isoenzymes of skeletal muscle demonstrated only minimal recovery.
Environment and health: 9. The science of risk assessment

Potential hazards surround us at home, in the workplace, in our cars and even in health care facilities. Given exposure to these hazards, we may want to evaluate the risk that an adverse event will occur or that it will occur at some level of severity. In this article we introduce some concepts
Tailored Mesoporous Silicas: From Confinement Effects to Catalysis

Ordered mesoporous silicas continue to find widespread use as supports for diverse applications such as catalysis, separations, and sensors. They provide a versatile platform for these studies because of their high surface area and the ability to control pore size, topology, and surface properties over wide ranges. Furthermore, there is a diverse array of synthetic methodologies for tailoring the pore surface with organic, organometallic, and inorganic functional groups. In this paper, we will discuss two examples of tailored mesoporous silicas and the resultant impact on chemical reactivity. First, we explore the impact of pore confinement on the thermochemical reactivity of phenethyl phenyl ether (PhCH2CH2OPh, PPE), which is a model of the dominant {beta}-aryl ether linkage present in lignin derived from woody biomass. The influence of PPE surface immobilization, grafting density, silica pore diameter, and presence of a second surface-grafted inert 'spacer' molecule on the product selectivity has been examined. We will show that the product selectivity can be substantially altered compared with the inherent gas-phase selectivity. Second, we have recently initiated an investigation of mesoporous silica supported, heterobimetallic oxide materials for photocatalytic conversion of carbon dioxide. Through surface organometallic chemistry, isolated M-O-M species can be generated on mesoporous silicas that,more » upon irradiation, form metal to metal charge transfer bands capable of converting CO{sub 2} into CO. Initial results from studies of Ti(IV)-O-Sn(II) on SBA-15 will be presented.« less
Optimization and experimental validation of electrostatic adhesive geometry

This paper introduces a method to optimize the electrode geometry of electrostatic adhesives for robotic gripping, attachment, and manipulation applications. Electrostatic adhesion is achieved by applying a high voltage potential, on the order of kV, to a set of electrodes, which generates an electric field. The electric field polarizes the substrate material and creates an adhesion force. Previous attempts at creating electro-static adhesives have shown them to be effective, but researchers have made no effort to optimize the electrode configuration and geometry. We have shown that by optimizing the geometry of the electrode configuration, the electric field strength, and therefore the adhesion force, is enhanced. To accomplish this, Comsol Multiphysics was utilized to evaluate the average electric field generated by a given electrode geometry. Several electrode patterns were evaluated, including parallel conductors, concentric circles, Hilbert curves (a fractal geometry) and spirals. The arrangement of the electrodes in concentric circles with varying electrode widths proved to be the most effective. The most effective sizing was to use the smallest gap spacing allowable coupled with a variable electrode width. These results were experimentally validated on several different surfaces including drywall, wood, tile, glass, and steel. A new manufacturing process allowing for the fabrication of thin, conformal electro-static adhesive pads was utilized. By combining the optimized electrode geometry with the new fabrication process we are able to demonstrate a marked improvement of up to 500% in shear pressure when compared to previously published values.
Theoretical evaluation of new nucleic acid bases. II. Ab initio study on tautomerism of pyrazolo[4,3-d]pyrimidine-5,7 (4H,6H)-dione

Abstract The four most important tautomers of the title compound were studied by the ab initio LCAO-MO method at the MP2/ 6-31G**//HF/3-21G level. All calculated structures are minima at the HF/3-21G potential energy surface with the dioxo tautomer 1 being the global minimum. Also in a polar environment 1 is predicted to be a predominant form. The second most stable species, oxo—hydroxy tautomer 2 has a relative energy of 38.7 kJ mol −1 MP2/6-31G** + 0.9 ZPE). For the 1 → 2 transition the calculated energy gap corresponds to an equilibrium constant of 10 −1 which is only one order larger than the estimated frequency threshold of spontaneous mutations and it strongly suggests that π is a new purine base with reduced probability of spontaneous mutations.
West nile virus surveillance: A simple method for verifying the integrity of RNA in mosquito (Diptera: Culicidae) pools

In a West Nile virus (WNV) -free ecosystem, it is essential to verify the integrity of RNA before concluding that RNA extracted from mosquito specimens is negative for WNV gene sequences. The primary objective of our study was to develop a rapid molecular assay to rapidly screen mosquitoes for the presence of 18S RNA and WNV gene sequences. Mosquitoes, collected from multiple sites on the island of O'ahu, were pooled into groups of 1-50 mosquitoes according to capture site, date, and species. Using primer design software and the GenBank database, generic oligonucleotide primer pairs were designed to amplify mosquito18S rRNA gene sequences from different species. RNA was extracted from mosquito pools, and reverse transcriptase-polymerase chain reaction (RT-PCR) was performed for the presence of mosquito18S rRNA and WNV gene sequences. Three of the seven primer pairs successfully detected 18S rRNA sequences for both Aedes and Culex by RT-PCR, and one primer pair successfully amplified 18S rRNA sequences for 15 different mosquito species. All 64 mosquito pools from 10 different sites on the island of Oahu, Hawaii, were negative for WNV nonstructural protein-5 gene sequences. This simple, one-step RT-PCR method for screening mosquito pools for arboviruses will become an increasingly valuable tool as WNV becomes endemic throughout the Americas.
Exchange Rates And Equity Markets: Evidence From Some European Countries

This paper employs cointegration analysis, vector error correction and vector autoregressive modeling along with Granger causality tests to examine the effect of exchange rates on the stock market indexes for a group of European Union countries using daily data from 1999-2009. The results suggest that the transmitting mechanism for the influence of the exchange rate in the stock market is foreign investment. Evidence also highlights that there is no clear causality from stock market to exchange rates, or vice versa, for the direction of the causation, suggesting that exchange rates and stock markets operate as an integrated system continuously influencing each other.
Applying tumor genotyping and new clinical approaches to the management of colorectal cancer.

The last two decades have seen a dramatic improvement in outcomes for patients with metastatic colorectal cancer (mCRC) with median survival now more than 30 months. This improvement in outcomes has come from a multidisciplinary approach to the care of patients with mCRC that combines systemic chemotherapy with improved surgical techniques, sophisticated radiologic interventions, and local therapy, and from the use of targeted drugs that have ushered in an era of genomic analysis in the standard care of mCRC. Treatment of mCRC is now individualized both based on pattern and extent of metastatic disease and tumor genetics, particularly mutations in oncogenes, such as KRAS, NRAS, and BRAF, and inactivation of the mismatch repair enzymes. In this special issue of the Journal of Gastrointestinal Oncology (JGO), applying tumor genotyping and new clinical approaches to the management of colorectal cancer, experts in the field review key advances in the management of CRC patients. The topics addressed in this issue encompass a variety of timely themes. Several articles address the use of genetic information in the management of CRC. Sylvester and Vakiani discuss genetic progression in mCRC and tumor heterogeneity between primary and metastatic CRC. Kawakami, Zaanan, and Sinicrope review implications of mismatch repair-deficient status on the management of early stage colorectal cancer. Clarke and Kopetz summarize the emerging understanding of BRAF mutant CRC as a distinct subset in CRC, and Corcoran discusses exciting early results in the targeting of these tumors. Finally, Lipsyc and Yaeger discuss recent data that oncogene mutations may affect the pattern of metastases of CRC. Several authors discuss advances in the treatment of patients with limited metastatic disease. McAuliffe, Qadan, and D’Angelica review advances in liver resection and hepatic arterial therapy for patients with colorectal cancer liver metastases. Ridge and Solomon review the use of radiofrequency ablation to treat colorectal lung metastases. Guend, Patel, and Nash discuss advances in the treatment of peritoneal-limited colorectal metastases and the use of intraperitoneal therapies. We believe this special issue of the JGO addresses many of the challenges and new approaches in the management of CRC. We hope you find it informative and enjoyable.