cssi/SciSciGPT-SciSciNet huggingface dataset:
Action of eledosin on isolated vascular strips.

Des bandelettes aortiques du lapin sont fortement stimulees par l'eledoisine. Apres pretraitement du lapin a la reserpine, l'aorte devient deux fois plus sensible a l'eledoisine que normalement. Cette sensibilisation envers l'eledoisine diminue apres incubation de l'aorte isolee avec la noradrenaline. Le meme pretraitement a la reserpine n'a pas augmente l'effet de l'eledoisine sur la veine isolee du lapin. Cette preparation par contre devient facilement tachyphylactique.
Properties of Slow, Cumulative Sodium Channel Inactivation in Rat Hippocampal CA1 Pyramidal Neurons

Sodium channels in the somata and dendrites of hippocampal CA1 pyramidal neurons undergo a form of long-lasting, cumulative inactivation that is involved in regulating back-propagating action potential amplitude and can influence dendritic excitation. Using cell-attached patch-pipette recordings in the somata and apical dendrites of CA1 pyramidal neurons, we determined the properties of slow inactivation on response to trains of brief depolarizations. We find that the amount of slow inactivation gradually increases as a function of distance from the soma. Slow inactivation is also frequency and voltage dependent. Higher frequency depolarizations increase both the amount of slow inactivation and its rate of recovery. Hyperpolarized resting potentials and larger command potentials accelerate recovery from slow inactivation. We compare this form of slow inactivation to that reported in other cell types, using longer depolarizations, and construct a simplified biophysical model to examine the possible gating mechanisms underlying slow inactivation. Our results suggest that sodium channels can enter slow inactivation rapidly from the open state during brief depolarizations or slowly from a fast inactivation state during longer depolarizations. Because of these properties of slow inactivation, sodium channels will modulate neuronal excitability in a way that depends in a complicated manner on the resting potential and previous history of action potential firing.
Software testing: a research travelogue (2000–2014)

Despite decades of work by researchers and practitioners on numerous software quality assurance techniques, testing remains one of the most widely practiced and studied approaches for assessing and improving software quality. Our goal, in this paper, is to provide an accounting of some of the most successful research performed in software testing since the year 2000, and to present what appear to be some of the most significant challenges and opportunities in this area. To be more inclusive in this effort, and to go beyond our own personal opinions and biases, we began by contacting over 50 of our colleagues who are active in the testing research area, and asked them what they believed were (1) the most significant contributions to software testing since 2000 and (2) the greatest open challenges and opportunities for future research in this area. While our colleagues’ input (consisting of about 30 responses) helped guide our choice of topics to cover and ultimately the writing of this paper, we by no means claim that our paper represents all the relevant and noteworthy research performed in the area of software testing in the time period considered—a task that would require far more space and time than we have available. Nevertheless, we hope that the approach we followed helps this paper better reflect not only our views, but also those of the software testing community in general.
Answering “What-If” Deployment and Configuration Questions With WISE: Techniques and Deployment Experience

Designers of content distribution networks (CDNs) often need to determine how changes to infrastructure deployment and configuration affect service response times when they deploy a new data center, change ISP peering, or change the mapping of clients to servers. Today, the designers use coarse, back-of-the-envelope calculations or costly field deployments; they need better ways to evaluate the effects of such hypothetical “what-if” questions before the actual deployments. This paper presents What-If Scenario Evaluator (WISE), a tool that predicts the effects of possible configuration and deployment changes in content distribution networks. WISE makes three contributions: 1) an algorithm that uses traces from existing deployments to learn causality among factors that affect service response time distributions; 2) an algorithm that uses the learned causal structure to estimate a dataset that is representative of the hypothetical scenario that a designer may wish to evaluate, and uses these datasets to predict hypothetical response-time distributions; 3) a scenario specification language that allows a network designer to easily express hypothetical deployment scenarios without being cognizant of the dependencies between variables that affect service response times. Our evaluation, both in a controlled setting and in a real-world field deployment on a large, global CDN, shows that WISE can quickly and accurately predict service response-time distributions for many practical what-if scenarios.
Measuring the impact of translation on the accuracy and fluency of vocabulary acquisition of English

HighlightsWe study how translation affects ESL vocabulary learning.A reading tutor using language technologies measures each student's learning.Use of translation increases the retrieval time of L2 lexical items.Excessive use of translation decreases long-term retention of L2 lexical items. This article assesses the impact of translation on the acquisition of vocabulary for higher-intermediate level students of English for Speakers of Other Languages (ESOL). The use of translation is a relevant issue in the research of Second Language (L2) acquisition and different authors provide arguments on both sides of the issue. Language technologies serve this issue in both the usability of automatic translation and the automatic detection of lexical phenomena. This paper will explore translation as it affects the acquisition of new words in context when students are given real texts retrieved from the Internet in a web-based interface. The students can instantly obtain the dictionary definition of a word and its translation to their native language. This platform can accurately measure how much each student relies on translation and compare this to their accuracy and fluency on a lexical retrieval task using words seen in the texts. Results show that abundant use of translation may increase accuracy in the short term, but in the longer term, it negatively affects accuracy and possibly fluency. However, students who use translation in moderation seem to benefit the most in this lexical task. This paper provides a focused and precise way to measure the relevant variables for each individual student, and new findings that contribute to our understanding of the impact of the use of translation in language learning.
Nonlinear stochastic trends

Abstract A nonlinear growth process has its change equal to a positive function of the lagged series plus an innovation whose variance depends on the lagged series. If the innovations were identically zero the resulting deterministic trends take a wide variety of shapes. The balance between growth in mean and variance to guarantee eventual growth of the process is determined, the relationship between stochastic and deterministic trends found, parametric and nonparametric estimates of the functions considered and applications analysed. The natural bivariate generalization is found to produce a form of cointegration and a nonlinear error-correction model.
An Expanded Taxonomy of Sorting Algorithms

I present an expanded taxonomy of sorting algorithms that is based upon Merritt's inverted taxonomy [1] and Lau's logic‐based derivations [2, 3]. The inverted taxonomy was based on a higher level, more abstract, and conceptually simple top‐down approach to sorting than the traditional taxonomy such as that given by Knuth [4], Work done in automatic program synthesis suggested the approach. Sorts were divided into two categories, hardsplit/easyjoin and easysplit/hardjoin, of which quicksort and mergesort are the canonical examples, respectively. Lau's [2, 3] logic‐based derivations strengthen the inverted taxonomy by deriving comparison‐based sorting algorithms that fall into the two categories of hardsplit/easyjoin and easysplit/hardjoin. Moreover, they expand the taxonomy by deriving distributive algorithms in a symmetric way.
Alkalinization in the Isolated and Perfused Anterior Midgut of the Larval Mosquito, Aedes aegypti

In the present study, isolated midguts of larval Aedes aegypti L. (Diptera: Culicidae) were mounted on perfusion pipettes and bathed in high buffer mosquito saline. With low buffer perfusion saline, containing m-cresol purple, transepithelial voltage was monitored and luminal alkalinization became visible through color changes of m-cresol purple after perfusion stop. Lumen negative voltage and alkalinization depended on metabolic energy and were stimulated in the presence of serotonin (0.2 micromol l(-1)). In some experiments a pH microelectrode in the lumen recorded pH values up to 10 within minutes after perfusion stop. The V-ATPase inhibitor concanamycin (50 micromol l(-1)) on the hemolymph side almost abolished V(te) and inhibited luminal alkalinization. The carbonic anhydrase inhibitor, methazolamide (50 micromol l(-1)), on either the luminal or hemolymph-side, or the inhibitor of anion transport, DIDS (1 mmol l(-1)) on the luminal side, had no effect on V(te) or alkalinization. Cl(-) substitution in the lumen or on both sides of the tissue affected V(te), but the color change of m-cresol purple was unchanged from control conditions. Hemolymph-side Na(+) substitution or addition of the Na(+)/H(+) exchange inhibitor, amiloride (200 micromol l(-1)), reduced V(te) and luminal alkalinization. Luminal amiloride (200 micromol l(-1)) was without effects on V(te) or alkalinization. High K(+) (60 mmol l(-1)) in the lumen reduced V(te) without affecting alkalinization. These results indicate that strong luminal alkalinization in isolated and perfused anterior midgut of larval A. aegypti depends on basolateral V-ATPase, but is apparently independent of carbonic anhydrase, apical Cl(-)/HCO(3)(-) exchange or apical K(+)/2H(+) antiport.
Stable nitrogen and carbon isotope ratios of beach tars on South Texas barrier islands

Abstract Stable nitrogen and carbon isotope analyses have been used to characterize two major oil spills in the northwestern Gulf of Mexico. Stable isotope ratios were determined on both the crude material and on discrete chemical fractions of the whole oil (aliphatic, aromatic and NOS). A comparison of these isotopic compositions, of the crude materials and their chemical fractions, with those from samples of beach tars collected from south Texas barrier islands has indicated at least sixteen distinct isotopic signatures in the beach tars, excluding those resembling the major spills. This variation may be indicative of multiple sources of oils stemming from exploration and transport activities. Multiple isotope analysis can be a useful tool in the resolution of origins of spilled oils and tars.
DARPA FCS unmanned ground vehicle research initiatives

The Defense Advanced Research Projects Agency (DARPA) and the US Army (ASAALT) have jointly funded several FCS research initiatives in ground robotics. The Unmanned Ground Combat Vehicle (UGCV) and Perception for Off-Road Mobility (PerceptOR) programs are the major elements of this joint ground robotic effort. These programs were initiated in fiscal year 2001 and have progressed through their first phase. The UGCV program, now in Phase IB, has downselected from 11 concepts designs to 4. Phase IB focuses on detailed design of teams' concepts in anticipation of the prototype construction Phase II and initial vehicle roll-out near the end of the 2002 calendar year. This paper highlights program findings to date as a result of the initial phase, and illustrates plans for Phase II prototype testing. The PerceptOR program, currently in Phase II, has completed its Phase I which involved development of a perception system for operation on a commercial All Terrain Vehicle. This paper describes the effort of the first phase, and outlines the plans for vehicle testing in Phases II and III.
Regulation of ribosomal RNA synthesis in sea urchin embryos and oocytes.

Abstract The steady-state concentrations and absolute rates of synthesis of ribosomal RNA (rRNA) molecules were measured in oocytes, eggs, embryos, and larvae of the Hawaiian sea urchin Tripneustes gratilla . The steady-state concentration per genome of the RNA precursor sequences measured by hybridization to a cloned rDNA fragment was approximately 100- to 300-fold greater in the RNA obtained from oocytes and eggs than in the RNA extracted from embryos and larvae. Since the rate of processing of the rRNA precursor at different stages is not greatly different, the rates of rRNA synthesis must be considerably greater in oocytes than in embryo cells. The absolute rate of RNA synthesis in oocytes and embryos was determined from the incorporation of [ 3 H]guanosine into cellular GTP pools and into both precursor and mature rRNA species. The data indicate an approximately 40-fold higher rate of rRNA synthesis in oocytes than that measured in embryos or previously in larvae ( J. Griffith and T. Humphreys, 1979, Biochemistry 18, 2178–2185 ). Together these results indicate that the ribosomal genes are transcribed much more rapidly during sea urchin oogenesis than during embryogenesis or larval stages.
Therapist specific communication styles and patient resistance: An analogue study

Abstract Two contrasting pairs of verbal therapist communication styles were covaried with three areas of communication loci and were studied in relation to subjects' choices of resistant or resonant ‘patient responses’. Thirty medical students, serving as vicarious patients, observed a videotape of a simulated psychotherapy session and made response choices in relation to 12 therapists' well-specified communications. Contrary to expectations, subjects chose fewer resistant responses following engaged styles of communication than with disengaged styles. Collaborative style of communication, as hypothesized, was followed by less resistant responses than was unidirectional style. Communications that were cast in terms of transferential relationships were generally followed by significantly lower resistant choices than were those relating to past and current relationship loci. No gender differences were observed. Rationale, findings and possible inferences were in relation to dyadic interpersonal influences....
Scaling down photonic waveguide devices on the SOI platform

We discuss the challenges encountered when scaling down photonic waveguide devices, and demonstrate possible solutions in silicon-on-insulator (SOI) platform. First, sources of waveguide birefringence such as waveguide geometry and stress in the waveguiding layer are discussed. Birefringence sensitivity to inaccuracy of waveguide dimensions is compared for different waveguide geometries, including trapezoidal and rectangular cross-sections. Results show that trapezoidal waveguides are more robust, which makes fabrication tolerances less stringent. Methods for minimizing the waveguide birefringence using stress induced by an over-cladding dielectric film, and by inducing form birefringence through deposition of thin layers of high and low refractive index materials, are discussed. Compact arrayed waveguide grating (AWG) devices are presented, with internal loss of -5.9 dB, crosstalk better than -20 dB, and polarization dependent wavelength shift of <0.05 nm. We discuss and quantify the sources of loss and crosstalk in our AWG devices, and review the methods we have developed for compensation of the polarization dependent wavelength shift, including etched compensator and silicon-oxide-silicon (SOS) compensator. The latter exploits form birefringence of a thin buried oxide layer sandwiched between silicon waveguide core and a silicon over-layer, and is simple to fabricate by standard oxide and amorphous silicon or polysilicon deposition techniques. The calculated loss penalty of the SOS compensator is less than 0.2 dB for both TE and TM polarization.
Increment thresholds against pulsed and steady backgrounds

Cornsweet and Pinsker reported that ΔL/L was constant at all values of L for briefly pulsed fields (ΔL was the luminance increment required for discriminating which of two nearby flashed fields was brighter). We obtain the same result when the subject must detect which of two briefly (4-msec) flashed backgrounds contains an increment at its center. However, when the background and increment are flashed at a longer duration (200 msec) ΔL/L decreases with increasing L as is obtained with a steady background. Two previous models which handle earlier work do not readily accommodate this result; we suggest a theoretical approach that does.
Drug Stability in Liposomal Suspensions: Hydrolysis of Indomethacin, Cyclocytidine, and p-Nitrophenyl Acetate

First-order rate constants (kL) for hydrolysis of p-nitrophenyl acetate, cationic cyclocytidine, and anionic indomethacin in the presence of buffered liposomal suspensions of positive, negative, and neutral charge were compared to those determined in the corresponding buffers (kB) using the ratio, Rk = kL/kB. Association between the reactants and the liposomes was evaluated by comparing assays for concentration in the filtrates (CF) with the total concentration in the liposomal suspension (CT) using RC = CF/CT. Liposomes did not influence cyclocytidine hydrolysis rates and no association was observed (Rk congruent to RC congruent to 1). In contrast, indomethacin showed approximately 80% reduction in hydrolysis rate and approximately 80% liposome association value (Rk congruent to 0.2 congruent to RC). In neutral and negatively charged liposomal suspensions, p-nitrophenyl acetate displayed approximately 30% decrease in kB (Rk congruent to 0.7) together with approximately 90% liposomal association (RC congruent to 0.1). However, hydrolysis was greatly accelerated in positively charged liposomal suspensions. Loss was described by a biexponential equation where alpha is the fast and beta is the slow pre-exponential coefficient and alpha/beta/kB = 39:6:1. The observed relationships between hydrolysis rates and reactant-liposome associations are reconciled in terms of the hydrophilicity of the reactants and the potential influence of the liposomes on the expected transition states for the hydrolysis reactions.
Solution Rheology of Saline and Polysaccharide Systems

The problem of the characterization of the solution properties of water soluble polymers is long-standing. These polymers tend to form aggregated supramolecular gels that are resistant to molecular dispersion. These materials are being widely used in a variety of industrial applications. Their principle functions are as rheological modifiers, where they thicken or gel solutions in products such as hair-care, detergents, air fresheners and foods; as flocculants for particle separation as applied to water clarification, sewage, and effluent treatment, and as stabilizers to control the properties of concentrated suspension and emulsions, for example in paints, pesticides, dyes, and pharmaceutical industries. Therefore it is important to understand their rheological properties under various operating conditions such as stress, strain, temperature etc, which will induce gelation. The rheological properties of starch gels of high concentration (up to 86% starch) have been investigated before [1]. In this paper we have investigated experimentally the shear viscosity and viscoelasticity properties of saline and polysaccharide suspensions at various low concentrations and pH at different temperatures using controlled stress and strain rheometers (Vilastic-3 and AR 2000). The data were then fitted with the power law and Cross model for low and higher concentrations respectively. The present results show that the viscosity/elasticity does not significantly change for low concentrations at different pH values. The maximum viscosity/elasticity was obtained around pH 5-7.4 at higher concentrations.Copyright © 2006 by ASME
A dynamic screen technique for shaded graphics display of slice-represented objects

Abstract We present a very rapid method of constructing realistic images of 3-dimensional (3D) objects on a 2-dimensional (2D) display screen. Our technique is well suited to objects represented by slices, since it traverses the slices in a front-to-back sequence relative to the observer, accessing each slice just once. A dynamic data structure—the dynamic screen—is used to represent the unlit screen pixels. When each slice is accessed, only unlit pixels are processed and newly-lit pixels are efficiently removed from the data structure. Implementation of the method for large medical objects results in display times significantly faster than previous software methods.
Memory effects during collisional energy transfer from highly excited CS2

Abstract Time dependent thermal lensing has been used to monitor energy transfer from CS 2 (optically excited at 31250 cm −1 ) to Kr gas at 50–600 Torr. The results show that the energy transferred per collision is significantly more efficient at lower collision frequencies: a memory effect. This can be explained with a model which includes collision-free radiationless transitions between excited electronic states and collisional vibrational relaxation within each electronic state. The model also explains why the bulk average energy transfer exhibits a dramatic transition in energy transfer efficiency at bulk average energies corresponding to the triplet state origin.
RALPH: rapidly adapting lateral position handler

Nearly 15,000 people die each year in the US in single vehicle roadway departure crashes. These accidents are often caused by driver inattention, or driver impairment (e.g. fatigued or intoxicated drivers). A system capable of warning the driver when the vehicle starts to depart the roadway, or controlling the lateral position of the vehicle to keep it in its lane, could potentially eliminate many of these crashes. This paper presents a system called RALPH (Rapidly Adapting Lateral Position Handler) which decomposes the problem of steering a vehicle into three steps, 1) sampling of the image, 2) determining the road curvature, and 3) determining the lateral offset of the vehicle relative to the lane center. The output of the later two steps are combined into a steering command, which can be compared with the human driver's current steering direction as part of a road departure warning system, or sent directly to the steering motor.
A comparison of reduced order model techniques

Four techniques for constructing reduced order models are compared. The techniques are based on: 1) truncating the balanced realization; 2) Laguerre series expansion; 3) Kautz series expansion; and 4) continued fraction expansion. These techniques will be used to construct reduced order models for the same (very simple) plant transfer function. Each reduced order model is then used to design a controller to achieve the same design objectives. Finally, the performance of the closed loop control systems that result from using each controller with the full order plant are compared. Several model reduction techniques produce virtually identical models and hence virtually identical.
Impact of Pharmacist-Conducted Medication Reconciliation at Discharge on Readmissions of Elderly Patients With COPD

Purpose: Beginning in fiscal year 2015, the Centers for Medicare and Medicaid Services will measure all-cause readmissions for patients admitted for exacerbation of chronic obstructive pulmonary disease (COPD). Hospitals will incur a payment penalty for unplanned 30-day readmissions. Elderly patients frequently present a challenge because of polypharmacy, which contributes to a greater risk for medication-related readmissions. Objective: To determine whether pharmacist-conducted medication reconciliation at discharge decreased medication discrepancies and reduced 30-day readmissions for elderly patients with COPD. Methods: Patients aged 65 years and olderadmitted for a COPD exacerbation between January 31, 2012, and February 29, 2012, were included. The pharmacist reviewed the discharge form for discrepancies. Patients who were readmitted within 30 days of discharge were identified. The rate of 30-day readmission was compared with baseline data. Length of stay and cost for admission versus readmission wer...
A New Treatment of Electron Tube Oscillators with Feed-Back Coupling

In an electron tube oscillator with feed-back coupling, the ratio E g /E p may be expressed as ϵ|i, in which ϵ and Φ are respectively called "excitation" and "phase difference." For the maintenance of self-oscillation it is absolutely necessary to have a correct Φ, and for the optimum intensity of self-oscillation there is usually a most favorable ϵ for a given oscillator. The complex ratio E g /E p is a function entirely of the constants outside of the tube (i. e., independent of the tube characteristics), provided the grid current and the effect of resistances on the oscillation frequency are assumed negligible. Expressions for E g /E p are given for several types of oscillators, which are derived from a general oscillator network containing three parallel resonant circuits connecting the plate, grid, and filament. All ordinary oscillators are subderivatives of these types and their expressions for E g /E p are easily obtained by applying special conditions. Numerical computations have been made for practically all special oscillators and the resulting values for ϵ and Φ are illustrated by curves from which considerable information concerning the operating behaviors of oscillators can be obtained. In a two-mesh oscillator there are two frequencies, at either of which the oscillation may take place. It is shown that only the wave which gives the correct Φ can be excited. Experimental check of the theory has been found quite satisfactory in most cases.
Xenobiotic-induced hepatotoxicity: mechanisms of liver injury and methods of monitoring hepatic function

Xenobiotic-induced liver injury is a clinically important etiology of hepatic disease that, if not recognized, can lead to hepatic failure. In this article we discuss the mechanisms of xenobiotic-induced liver injury, various factors that can alter the risk and severity of injury, the clinical and laboratory manifestations of injury, and the methods used to detect the presence of injury and (or) functioning liver mass.
Statins inhibit oxidized-LDL-mediated LOX-1 expression, uptake of oxidized-LDL and reduction in PKB phosphorylation

Objectives: LOX-1, a lectin-like receptor on endothelial cells, facilitates the uptake of oxidized-LDL. Expression of LOX-1 is involved in the pathobiological effects of oxidized-LDL in endothelial cells, including apoptosis, suppression of cNOS activity and cell adhesion. Recent studies show that intracellular signal protein kinase B (PKB) is involved in the regulation of cNOS. Further, HMG CoA reductase inhibitors (statins) may affect LOX-1 expression. In this study, we examined the modulation of LOX-1 expression and PKB activity in response to oxidized-LDL by two different statins (simvastatin and atorvastatin). Methods and results: Cultured human coronary artery endothelial cells (HCAECs) were used in this study. Oxidized-LDL (40 μg/ml) was found to upregulate the expression of LOX-1 (mRNA and protein), enhance [125I]-ox-LDL uptake and to reduce the phosphorylation of PKB (p-PKB). Two different statins, simvastatin and atorvastatin (each 1 and 10 μM), upregulated the activity of PKB and decreased LOX-1 expression and [125I]-ox-LDL uptake. A high concentration of statins (10 μM) gave a more potent effect than the low concentration (1 μM). The effects of the two different statins were similar. Conclusions: These observations show that statins decrease LOX-1 expression, a novel oxidized-LDL endothelial receptor, and uptake of oxidized-LDL in HCAECs. The effect of statins on LOX-1 expression is associated with an increase in PKB activity in HCAECs.
Knowledge management in non-collocated environments: a look at centralized vs. distributed design approaches

In the domain of project management, types of knowledge can be characterized as "knowledge in projects", "knowledge about projects", and "knowledge from projects". The use of information technology in the realm of knowledge management has been approached from two main angles: codification and personalization. In the following paper, we look at the implications that each technological approach has on the aggregation, transfer, and sensemaking of knowledge in distributed environments. Drawing on the strengths and limitations of each technique, we propose a hybrid model. Research questions pertaining to the management of knowledge systems are presented.
The ABCs of SMC proteins: two-armed ATPases for chromosome condensation, cohesion, and repair.

The first draft of the human genome sequence was reported a year ago. It may be a good time to remind ourselves that the genetic information encoded in the ∼3000-Mb sequence is stored not only in the public or private databases but also in the tiny space of the cell nucleus. The total length of human genomic DNA, which resides in 23 chromosomes, reaches approximately one meter. It is by no means a simple task to fold up the long DNA molecules and package them within a cell nucleus whose diameter is only ∼10 μm. Even more striking is that the DNA molecules are faithfully duplicated and segregated into two daughter cells in an extremely limited space. Although more than 100 years have passed since Walther Flemming first described the dynamic behavior of chromosomes (or mitosis) during cell division, it remains highly mysterious how this remarkable process of chromosome segregation is achieved at a mechanistic level. From a cytological point of view, two dramatic events occur on chromosomes during mitosis. The first one is the conversion of an amorphous mass of interphase chromatin into a discrete set of rod-shaped chromosomes (chromosome condensation), which occurs from prophase to metaphase (Koshland and Strunnikov 1996; Hirano 2000). The second is the splitting of chromosomes into two halves, which takes place highly synchronously at the onset of anaphase (Dej and Orr-Weaver 2000; Nasmyth et al. 2000). As a crucial prerequisite for these events, duplicated chromosomes (sister chromatids) must be held together immediately after DNA replication in S phase and throughout G2 phase. The importance of this process (sister chromatid cohesion) has been fully appreciated only recently because the pairing of sister chromatids cannot be visualized by classical cytology before chromosomes condense in early mitosis. Recent genetic and biochemical studies have begun to shed light on the molecular mechanisms underlying cohesion, condensation, and separation of chromosomes during the mitotic cell cycle. One of the unexpected findings is that chromosome condensation and sister chromatid cohesion are regulated by distinct, yet structurally similar, protein complexes termed condensin and cohesin, respectively. At the heart of the two protein complexes lie members of a family of chromosomal ATPases, the structural maintenance of chromosomes (SMC) family. Equally intriguing, SMC proteins are found in most, if not all, bacterial and archaeal species, implicating that their fundamental contribution to chromosome dynamics started even before the acquisition of histones during evolution. The goal of this review article is to discuss the current understanding of higher-order chromosome dynamics with an emphasis on the role of SMC proteins. I start with the basic description and classification of SMC proteins and then summarize emerging information on the diverse chromosomal functions supported by SMC proteins. Finally, I discuss the mechanistic aspects of bacterial and eukaryotic SMC proteins and try to make an integrated picture of their seemingly different actions.
Effects of Anesthesia on Sensory Evoked Potentials in Chicken Brain

Abstract In the course of experiments tracing sensory pathways in the brain of chickens, several anesthetics were used at various times, and it became of interest to determine what effect different anesthetics might be having on the results. This information is also helpful in comparing results of authors using different anesthetics. The anesthetics we used were pentobarbital sodium, urethan, and alpha chloralose. Responses recorded from chronically-implanted electrodes to standard flash stimuli were compared in each bird using all three anesthetics and no anesthetic. The birds used for the experiments were a series of chickens with permanently implanted electrodes that were being used for studies of behavior evoked by intracranial electrical stimulation. Each of these birds had fifteen electrodes implanted stereotaxically in various parts of the brain. The electrodes were soldered to the contacts of an Amphenol cable connector cemented to the skull. After behavior testing was completed the birds were tested…
Metabolic Interactions of Alcohol and Folate

The goals and objectives of these studies, conducted over the past 30 y, were to determine: a) how chronic alcoholism leads to folate deficiency and b) how folate deficiency contributes to the pathogenesis of alcoholic liver disease (ALD). The intestinal absorption of folic acid was decreased in binge drinking alcoholics and, prospectively, in volunteers fed alcohol with low folate diets. Monkeys fed alcohol for 2 y developed decreased hepatic folate stores, folic acid malabsorption and decreased hepatic uptake but increased urinary excretion of labeled folic acid. Micropigs fed alcohol for 1 y developed features of ALD in association with decreased translation and activity of intestinal reduced folate carrier. Another study in ethanol-fed micropigs demonstrated abnormal hepatic methionine and DNA nucleotide imbalance and increased hepatocellular apoptosis. When alcohol feeding was combined with folate deficiency, micropigs developed typical histological features of ALD in 14 wk, together with elevated plasma homocysteine levels, reduced liver S-adenosylmethionine and glutathione and increased markers for DNA and lipid oxidation. In summary, chronic alcohol exposure impairs folate absorption by inhibiting expression of the reduced folate carrier and decreasing the hepatic uptake and renal conservation of circulating folate. At the same time, folate deficiency accelerates alcohol-induced changes in hepatic methionine metabolism while promoting enhanced oxidative liver injury and the histopathology of ALD.
Implementation of online distributed system-level diagnosis theory

The practical application and implementation of online distributed system-level diagnosis theory is documented. Proven distributed diagnosis algorithms are shown to be impractical in real systems due to high resource requirements. A distributed system-level diagnosis algorithm called Adaptive DSD is shown to minimize network resources and has resulted in a practical implementation. Adaptive DSD assumes a distributed network, in which network nodes can test other nodes and determine them to be faulty or fault-free. Tests are issued from each node adaptively and depend on the fault situation of the network. Test result reports are generated from test results and forwarded between nodes in the network. Adaptive DSD is proven correct in that each fault-free node reaches an accurate independent diagnosis of the fault conditions of the remaining nodes. No restriction is placed on the number of faulty nodes; any fault situation with any number of faulty nodes is diagnosed correctly. An implementation of the Adaptive DSD algorithm is described. >
Fabrication of Nanoshell Arrays Using Directed Assembly of Nanospheres

Extraordinary transmission of light has been observed when light is incident on periodic nanostructures patterned metal films, which results from the interaction between the incident photons and the excited surface plasmon polaritons with wavenumbers constrained by the geometry and periodicity of the surface structure. Usually, the surface patterns are fabricated by Focused Ion Beam (FIB) milling, which is expensive and has low throughput. We employ the nanosphere lithography method to fabricate periodic nanoshell arrays on a gold film as an alternative to FIB milling. In this process, polystyrene nanospheres are deposited on glass substrates as a template for subsequent gold deposition. This results in the close-packed hexagonal nanoshell arrays patterned gold surface. The transmission spectra of the patterned surfaces show strong enhanced transmission in the red and IR wavelength regions, and the peak enhanced transmission wavelengths vary with the chemical environments above the surface.
Small‐comet “atmospheric holes” are instrument noise

Frank and Sigwarth claim that dark pixel clusters observed by the VIS Earth Camera are atmospheric holes created by small comets. We have examined their catalog, which contains about 700,000 of these “atmospheric holes”, for consistency with this small-comet hypothesis and with instrument noise. A geometrical requirement of the small-comet hypothesis is that the number of pixels in a typical cluster must vary by a factor > 100 with spacecraft altitude because of the inverse-square law of the apparent cluster area versus distance. We find no systematic variation of duster size with spacecraft altitude. The Iowa catalog data are consistent with instrument noise because neither the size distribution nor the event rate of dark pixel clusters depend on altitude. At altitudes outside of the radiation belts during the one day of available raw data, more than 75% of the dark pixel dusters result from the process that Frank and Sigwarth employ to remove bright pixels caused by energetic particles. This data processing also causes additional meaningless dark pixel clusters to occur in the dark sky or over the dark Earth.
The Implications of the “Virtual Water Trade” and Virtual Environmental Degradation Trade for the São Francisco River Basin in Brazil

Food production has an enormous impact on natural systems in both hydrological and ecological ways. In 2000, agriculture accounted for 67% of the total freshwater withdrawal in the world (UNEP, 2002). For the period of 1998-2002, that figure was 62% for Brazil (FAO, 2005). Water used in the production process of an agricultural or industrial good is ‘virtual water’ contained in the product. The ‘virtual water’ flow between nations is usually accompanied by a virtual environmental degradation current. Nations are exchanging surface and groundwater depletion, water pollution, soil erosion, and other negative externalities, which result from crop production. Such commerce involves trade-offs and unaccounted and unpaid environmental costs. Brazil has historically played the role of exporter of primary products, and consequently exports ‘virtual water’ to world food markets. The exportation of agricultural products causes a net transference of freshwater resources among regions and nations. I employ Hoekstra and Hung (2002)’s method to estimate the virtual water exported by the Rio Sao Francisco (SF) River Basin through grapes and mangos. What are the implications for semi-arid regions such as the Brazilian Northeast, which have chronically suffered from water shortage? What are other environmental consequences? This research analyzes the hydrological and ecological implications for local and regional systems resulting from selected primary sector activity taking into account virtual water transference and provides recommendations on more sustainable practices to reduce the loss of water and the environmental degradation of that river basin environment.
How ProÞtable Is Capital Structure Arbitrage

This paper examines the risk and return of the so-called capital structure arbitrage, which exploits the mispricing between a companys debt and equity. SpeciÞcally, a structural model connects a companys equity price with its credit default swap (CDS) spread. Based on the deviation of CDS market spreads from their theoretical counterparts, a convergence-type trading strategy is proposed and analyzed using 135,759 daily CDS spreads on 261 obligors. At the level of individual trades, the risk of the strategy arises when the arbitrageur shorts CDS and the market spread subsequently skyrockets, forcing the arbitrageur into early liquidation and engendering large losses. An equally-weighted portfolio of all trades produces Sharpe ratios similar to those of other Þxed-income arbitrage strategies and hedge fund industry benchmarks. However, the monthly excess returns on this portfolio are not signiÞcantly correlated with either equity or bond market factors.
Characterization of the beta 2-microglobulin endocytic pathway in rat proximal tubule cells

The uptake mechanism(s) of low-molecular-weight proteins by proximal tubule cells remains incompletely characterized. We utilized a biochemical and semiquantitative morphological approach to better characterize the endocytic pathway of an anionic protein, beta 2-microglobulin (beta 2M), in the rat proximal tubule. Indirect immunogold techniques revealed beta 2M was taken up via a classic receptor-mediated endocytic pathway. In vitro biochemical and morphological characterization of iodinated beta 2M and gold-conjugated beta 2M (gold-beta 2M) binding to isolated brush-border membrane vesicles (BBMV) documented specific and quantitatively similar binding interactions of the modified beta 2M with BBMV. Kinetic characterization of the in vivo endocytic pathway of gold-beta 2M was undertaken using microinfusion of individual tubules. beta 2M initially bound at the apical surface, was internalized into subapical coated vesicles and delivered to endosomal-like structures within 5 min, and, finally, was concentrated in lysosomal-like structures within 15 min. This uptake was inhibited by excess unconjugated beta 2M. In addition, we directly showed that uptake did not occur across the basolateral surface. Finally, by passing solubilized BBMV over beta 2M affinity columns we were able to isolate binding activity.
The Developmental Toxicity of Complex Silica-Embedded Nickel Nanoparticles Is Determined by Their Physicochemical Properties.

Complex engineered nanomaterials (CENs) are a rapidly developing class of structurally and compositionally complex materials that are expected to dominate the next generation of functional nanomaterials. The development of methods enabling rapid assessment of the toxicity risk associated with this type of nanomaterial is therefore critically important. We evaluated the toxicity of three differently structured nickel-silica nanomaterials as prototypical CENs: simple, surface-deposited Ni-SiO2 and hollow and non-hollow core-shell Ni@SiO2 materials (i.e., ~1–2 nm Ni nanoparticles embedded into porous silica shells with and without a central cavity, respectively). Zebrafish embryos were exposed to these CENs, and morphological (survival and malformations) and physiological (larval motility) endpoints were coupled with thorough characterization of physiochemical characteristics (including agglomeration, settling and nickel ion dissolution) to determine how toxicity differed between these CENs and equivalent quantities of Ni2+ salt (based on total Ni). Exposure to Ni2+ ions strongly compromised zebrafish larva viability, and surviving larvae showed severe malformations. In contrast, exposure to the equivalent amount of Ni CEN did not result in these abnormalities. Interestingly, exposure to Ni-SiO2 and hollow Ni@SiO2 provoked abnormalities of zebrafish larval motor function, indicating developmental toxicity, while non-hollow Ni@SiO2 showed no toxicity. Correlating these observations with physicochemical characterization of the CENs suggests that the toxicity of the Ni-SiO2 and hollow Ni@SiO2 material may result partly from an increased effective exposure at the bottom of the well due to rapid settling. Overall, our data suggest that embedding nickel NPs in a porous silica matrix may be a straightforward way to mitigate their toxicity without compromising their functional properties. At the same time, our results also indicate that it is critical to consider modification of the effective exposure when comparing different nanomaterial configurations, because effective exposure might influence NP toxicity more than specific “nano-chemistry” effects.
The Supreme Court's Quiet Expansion of the Qualified Immunity Defense

This essay discusses the Supreme Court’s tendency in recent opinions to covertly expand the reach of the qualified immunity defense available to public officials in § 1983 civil rights suits. In particular, the article points out that the Court, often in per curiam rulings, has described qualified immunity in increasingly broad terms and has qualified and retreated from its precedents, without offering any explanation or even acknowledging that it is deviating from past practice.In making this claim, I focus on three specific issues: the manner in which the Court characterizes the standard governing the qualified immunity defense; the question whether lower court opinions can clearly establish constitutional law so as to defeat a claim of qualified immunity; and the relationship between qualified immunity and Fourth Amendment doctrine. In each of these areas, the essay demonstrates, the Court has inexplicably broadened the protection qualified immunity affords government officials in § 1983 litigation.The article concludes that, while the most troubling aspect of this pattern is the suggestion that only the Supreme Court can create clearly established law, the differences in the terminology the Court has recently used in describing the qualified immunity defense and in comparing it to Fourth Amendment standards are not inconsequential. In particular, this change in tone runs the risk of placing a thumb on the scales favoring public officials in civil rights litigation.
Are intracytoplasmic sperm injection and high serum estradiol compounding risk factors for adverse obstetric outcomes in assisted reproductive technology

Objective To evaluate whether intracytoplasmic sperm injection (ICSI) use and E 2 on the final day of assisted reproductive technology (ART) stimulation are associated with adverse obstetric complications related to placentation. Design Retrospective cohort study. Setting Large private ART practice. Patient(s) A total of 383 women who underwent ART resulting in a singleton live birth. Intervention(s) None. Main Outcome Measure(s) Adverse placental outcomes composed of placenta accreta, placental abruption, placenta previa, intrauterine growth restriction, preeclampsia, gestational hypertension, and small for gestational age infants. Result(s) Patients with adverse placental outcomes had higher peak serum E 2 levels and were three times more likely to have used ICSI. Adverse placental outcomes were associated with increasing E 2 (odds ratio 1.36, 95% confidence interval 1.13–1.65) and ICSI (odds ratio 3.86, 95% confidence interval 1.61–9.27). Adverse outcomes increased when E 2 was >3,000 pg/mL and continued to increase in a linear fashion until E 2 was >5,000 pg/mL. The association of ICSI with adverse outcomes was independent of male factor infertility. Interaction testing suggested the adverse effect of E 2 was primarily seen in ICSI cycles, but not in conventional IVF cycles. Estradiol >5,000 pg/mL was associated with adverse placental events in 36% of all ART cycles and 52% of ICSI cycles. Conclusion(s) ICSI and elevated E 2 on the day of hCG trigger were associated with adverse obstetric outcomes related to placentation. The finding of a potential interaction of E 2 and ICSI with adverse placental events is novel and warrants further investigation.