cssi/SciSciGPT-SciSciNet huggingface dataset:
On link asymmetry and one-way estimation in wireless sensor networks

Link asymmetry is one of the unique challenges that wireless sensor networks pose in the design of network protocols. We observe, based on testbed experiments, that a substantial percentage of links are asymmetric, many are even unidirectional. We also find that the reliability of synchronous acknowledgments is considerably higher than that of asynchronous messages. Thus the norm of estimating link quality bidirectionally via asynchronous beacons underestimates the link reliability of asymmetric links. This leads us to investigate how to exploit asymmetric links in order to improve network functions such as convergecast routing in sensor networks via one-way link estimation. We propose a new one-way link metric ETF (for the expected number of transmissions over forward links) and present a local procedure for its estimation. We use ETF to identify reliable forward links, and we use dynamic retransmission thresholding for error control. Via experiments on testbeds of CC1000 radios and CC2420 radios (an IEEE 802.15.4-compliant radio), we quantify the performance improvement in ETF as compared with ETX. We also study the performance improvement of ETF over ETX when no special mechanism is employed to discover asymmetric links or to control retransmissions.
Acute D2/D3 dopaminergic agonism but chronic D2/D3 antagonism prevents NMDA antagonist neurotoxicity.

Background Antagonists of the N-methyl-D-aspartate (NMDA) glutamate receptor, most likely by producing disinhibtion in complex circuits, acutely produce psychosis and cognitive disturbances in humans, and neurotoxicity in rodents. Studies examining NMDA Receptor Hypofunction (NRHypo) neurotoxicity in animals, therefore, may provide insights into the pathophysiology of psychotic disorders. Dopaminergic D2 and/or D3 agents can modify psychosis over days to weeks, suggesting involvement of these transmitter system(s). Methods We studied the ability of D2/D3 agonists and antagonists to modify NRHypo neurotoxicity both after a one-time acute exposure and after chronic daily exposure. Results Here we report that D2/D3 dopamine agonists, probably via D3 receptors, prevent NRHypo neurotoxicity when given acutely. The protective effect with D2/D3 agonists is not seen after chronic daily dosing. In contrast, the antipsychotic haloperidol does not affect NRHypo neurotoxicity when given acutely at D2/D3 doses. However, after chronic daily dosing of 1, 3, or 5 weeks, haloperidol does prevent NRHypo neurotoxicity with longer durations producing greater protection. Conclusions Understanding the changes that occur in the NRHypo circuit after chronic exposure to dopaminergic agents could provide important clues into the pathophysiology of psychotic disorders.
Measuring Colloidal Forces Using Differential Electrophoresis

Differential electrophoresis is a technique for studying the forces holding two Brownian particles in a doublet configuration. The technique is based on the concept that particles having different zeta potentials (ζ) try to move at different velocities in an electric field but the colloidal forces holding the particles together frustrate the electrophoretic motion. A doublet with a dipole moment of ζ will rotate in an electric field; by measuring the angular velocity or stationary-state angular distribution, one is able to make conclusions about the rigidity of the doublet (i.e., whether or not there are forces acting tangentially to the surfaces of the two particles). At a sufficiently high electric field, the doublet aligns with the field and an electrophoretic displacement force tries to pull apart the doublet; this force, which is typically in the range 0.1−50 pN for micron size particles, can be calculated precisely from the electric field and known properties of the system. The doublet breaks if the...
Dose response to inhaled nitric oxide in pediatric patients with pulmonary hypertension and acute respiratory distress syndrome

Abstract Objective: To determine the pulmonary vascular functional dose response to inhaled nitric oxide (NO) for infants and children with acute respiratory distress syndrome and pulmonary artery hypertension. Design: Prospective, clinical observational study. Setting: Thirteen-bed pediatric intensive care unit at a 168-bed children's hospital. Patients: Infants and children requiring mechanical ventilation with an oxygenation index greater than 10. Methods: Children with severe acute respiratory distress syndrome received inhalation therapy with NO after conventional mechanical ventilation failed to result in improvement. Inhaled NO was sequentially titrated from 10 parts per million to 20, 40, 60, and 80 ppm at 10-minute intervals. A reduction of at least 30% in the pulmonary vascular resistance index (PVRI), or a reduction in mean pulmonary artery pressure of at least 10%, or an increase in the hypoxemia score of at least 20%, or a decrease in the oxygenation index of at least 20% from pretreatment values was considered a therapeutic response. After sequential titration, children who responded received continuous inhaled NO at the lowest dose associated with a therapeutic response. Results: Fourteen children received 15 trials with inhaled NO (median age, 63.4 months; range, 0.4 to 201 months). One patient's condition deteriorated during the titration phase, unrelated to NO treatment, and the patient was withdrawn from the study protocol. The mean (±SD) pretreatment oxygenation index was 35 ± 15, which decreased to 32 ± 20 at 80 ppm of inhaled NO ( p = 0.01). Ten children had pulmonary artery catheter measurements. The PVRI decreased by 30% or greater in seven children (70%). One child had a minimal decrease in PVRI during the titration phase but demonstrated an increase of more than 30% after NO therapy was discontinued. Mean pretreatment PVRI (270 ± 105) decreased to 207 ± 92 dynes/sec per cubic centimeter per square meter at 80 ppm of inhaled NO ( p = 0.06). Pretreatment mean pulmonary artery pressure (31 ± 7) decreased to 28 ± 5 mm Hg at 80 ppm of inhaled NO ( p = 0.04). Six trials (43%) showed an increase of 20% or greater in their hypoxemia score. Maximum improvement in the hypoxemia score and reduction in OI, PVRI, and mean pulmonary artery pressure occurred at 20 to 40 ppm of NO. Ten trials led to continuous inhaled NO therapy ranging from 7 to 661.5 hours, with a median of 47 hours. Systemic hypotension was not observed in any patient, and the maximum methemoglobin level was 5%. Conclusion: Inhaled NO appears to be a safe, although variably effective, therapy for the treatment of infants and children with acute respiratory distress syndrome. The maximum dose response occurs between 20 and 40 ppm of inhaled NO. Systemic side effects did not occur in any child who received NO therapy. (J Pediatr 1997;131:63-9)
Brain surface scanning using structured light

A significant problem in 3D reconstruction of biological tissue from histological material is alignment of the individual sections. We are developing a method to determine the surface of the tissue prior to cryosectioning and then utilize that information to guide registration. Toward that end, we have developed a structured light techniuqe for imaging frozen rat brains. The imaging approach relies on a novel coding scheme for the projected light which is based on 2D perfect submaps. Perhaps submaps are r by v c-ary arrays in which every n by m c-ary submatrix is unique. This coding scheme offers two major advantages over previous structured light patterns critical in the present application. It permits rapid image capture and, because each subwindow is unique, is robust in the presence of partial occlusion. To examine the accuracy of this technique, we compare the points mapped using it to the surface produced by block-face imaging. In the later approach, the tissue block is imaged prior to collecting each of the tissue sections. Since the block can be accurately repositioned after each cutting stroke, reconstruction of the surface from the block-face images is straightforward.
Multi‐functional coordination crosslinks in poly(vinylamine) complexes with cobalt chloride

Poly(vinylamme) complexes with cobalt chloride hexahydrate exhibit the largest glass transition temperature enhancements that have been measured in this laboratory. Tg increases from 56°C in the undiluted polymer to 193°C when the molar concentration of cobalt is only 3%, based on the moles of polymeric repeat units. This translates to a 45°C enhancement in Tg per mol% cobalt. Higher glass transition temperatures have been measured for other polymeric complexes with d-block salts, but this study reports the largest ΔTg=Tg(complex)-Tg(undiluted polymer) when transition-metal catalyzed chemical crosslinking reactions do not occur. A plausible explanation for this effect is based on the fact that cobalt chloride hexahydrate maintains pseudo-octahedral symmetry in the undiluted crystalline state and in an amorphous glassy complex with the polymer. The lone pair on nitrogen in the amino sidegroup is a strong base and, most likely, displaces all four waters of hydration that coordinate directly to the metal center. In fact, estimates of the ligand field splitting and the ligand field stabilization energy for octahedral cobalt complexes that contain methyl amine (CH3NH2) model ligands suggest that five or six amino sidegroups from several different chains might coordinate to each metal center, drastically reducing the mobility of the polymer. Both chloride anions remain near each divalent Co2+ center, but either one or two Cl− might not reside in the first-shell coordination sphere of the transition metal. This bonding picture suggests that octahedral cobalt acts as a multi-functional bridge between five or six amino sidegroups. Empirical ligand field stabilization calculations support the concept that octahedral Co2+ is a multi-functional coordination crosslinking agent, and the inorganic literature provides experimental verification that similar small-molecule complexes (i.e., [Co(NH3)6]2+) exist. It is proposed that the onset of Tg occurs when sufficient thermal energy is supplied to remove either x or (x-1) amino sidegroup ligands from the coordination sphere of cobalt, where x is either 5 or 6. This is an endothermic process based on bond energies, as well as calculations which focus on the relative energies of the metal d-electrons.
NMR and computational study of Ba8CuxGe46-x clathrate semiconductors

Ba 8 Cu x Ge 46x is a type-I clathrate material that forms as a semiconductor in a narrow composition range corresponding to the electron-balanced Zintl composition, withx= 5.3. We use NMR spectroscopy combined withab-initioelectronic structure calculations to probe the electronic and structural behavior of these materials. Computational results based on a superstructure model for the atomic configuration of the alloy provide good agreement with the electric quadrupole-broadened NMR lineshapes. Modeling using the modified Becke-Johnson (TB-mBJ) exchange potential is also shown to agree well with experimental NMR Knight shifts. The results indicate that the Cu-Ge balance is the main factor determining the carrier density, within a narrow stability range near the ideal Zintl composition.
Optical properties and laser action of H3 center in synthetic diamond

Color centers in diamond have a potential for opto-electronic applications. Laser action of H3 centers in natural diamond has been already reported. Our interest is focused on the possibility of laser action using synthetic diamond. A first attempt was made to produce H3 centers with high density in synthetic diamond. Optical properties of the H3 centers were investigated. Sample-dependent luminescence decay time and long lived transient absorption were observed. Laser action using the H3 centers in synthetic diamond occurred though the efficiency was as low as 0.1%.
Effects of molasses-based creep-feeding supplementation on growth performance of pre- and post-weaned beef calves

Abstract Two 2-year experiments were conducted to evaluate the effects of molasses-based creep-feeding supplements fortified with DL-methionine hydroxyl analog (MHA; Exp 1), or different supplemental nitrogen sources (Exp. 2), on growth performance of pre- and post-weaned beef calves. In both experiments, cows and calves were stratified by calving date and randomly assigned to pastures ( n =8 and 12 pastures for Exp. 1 and 2, respectively). Treatments were randomly assigned to pastures. In Exp. 1, treatments consisted of no creep-feeding supplementation ( NoCreep ), creep-feeding supplementation of sugarcane molasses plus 4% of a 50:50 urea+hot water blend (as-fed; Mol+U ) or Mol+U plus 0.22% of MHA (as-fed; Mol+MHA ). In Exp. 2, treatments consisted of NoCreep, creep-feeding supplementation of sugarcane molasses added with 4% of 50:50 urea+hot water blend (50:50, as-fed; Mol+U ) or 20% cottonseed meal (as-fed; Mol+CSM ). Calves were supplemented in cow exclusion areas for 122, 117, 104 and 102 days prior to weaning in years 1 and 2 of Exp. 1 and 2, respectively. In year 2 (Exp. 2), 18 heifers (2 heifers/pen; 3 pens/treatment) were randomly selected for a 17-day post-weaning evaluation and were provided free-choice access to a grain-based concentrate. In Exp. 1, Mol+U calves had similar ( P =1.00) voluntary creep-feed supplement intake in year 1, but greater ( P P =0.39) by treatment. In Exp. 1, but not in Exp. 2, creep-feeding supplementation increased ( P ≤0.01) calf BW at weaning and pre-weaning ADG compared with NoCreep calves. Calves supplemented with MHA had lesser ( P =0.03) pre-weaning ADG than Mol+U calves. In Exp. 2, nitrogen source added to creep-feed supplement did not affect ( P =0.15) calf pre-weaning ADG. Additionally, pre-weaning creep-feeding supplementation of heifers did not affect ( P ≥0.25) post-weaning growth performance or plasma concentrations of haptoglobin and fibrinogen during the receiving period. At weaning, heifers fed Mol+U had greater ( P =0.03) plasma concentrations of ceruloplasmin (Cp) than Mol+CSM heifers (23.8 versus 18.7±1.62 mg/dL, respectively), with NoCreep heifers being intermediate. On day 9, relative to weaning, Mol+U heifers had greater ( P =0.03) plasma Cp concentrations than NoCreep heifers (31.6 versus 26.6±1.62 mg/dL, respectively), with Mol+CSM heifers being intermediate. In conclusion, molasses-based creep-feed supplements increased pre-weaning growth performance of calves in Exp. 1, but not in Exp. 2, and did not affect post-weaning growth performance of heifers.
Protein aggregation and protein instability govern familial amyotrophic lateral sclerosis patient survival.

The nature of the “toxic gain of function” that results from amyotrophic lateral sclerosis (ALS)-, Parkinson-, and Alzheimer-related mutations is a matter of debate. As a result no adequate model of any neurodegenerative disease etiology exists. We demonstrate that two synergistic properties, namely, increased protein aggregation propensity (increased likelihood that an unfolded protein will aggregate) and decreased protein stability (increased likelihood that a protein will unfold), are central to ALS etiology. Taken together these properties account for 69% of the variability in mutant Cu/Zn-superoxide-dismutase-linked familial ALS patient survival times. Aggregation is a concentration-dependent process, and spinal cord motor neurons have higher concentrations of Cu/Zn-superoxide dismutase than the surrounding cells. Protein aggregation therefore is expected to contribute to the selective vulnerability of motor neurons in familial ALS.
The strategic audit: A game theoretic approach to corporate competitive strategy

To bring the highly developed quantitative approaches of middle management in accounting and control to the aid of corporate strategists is not easy. Specific operational problems are less overt and therefore formal optimization techniques are less easy to apply. The paper considers that the difficulty lies less in the absence of techniques and more in the failure of top management to state its objectives with precision. To do this a strategic audit is suggested. This can aid in goal specification. Industrial economics and game theory can then be applied to the problem so delineated.
Neuirofibroma of penis

Abstract We report a case of an isolated neurofibroma of the penis in a child with the stigmata of systemic neurofibromatosis (von Recklinghausen's disease).
Parameter Requirements for Noncooperative Satellite Maneuver Reconstruction Using Adaptive Filters

The Responsive Orbits division of the Center for Space Research and Assurance in the Aeronautics and Astronautics Department of the Air Force Institute of Technology investigates short-term tactical satellite missions that require frequent maneuvers. Pairing research in designing and conducting avoidance maneuvers with research in detecting and tracking maneuvering satellites sets the stage for developing and improving both areas. Strategies in stochastic filtering, smoothing, multiple model adaptive estimation, and maneuver reconstruction are developed to track a high-priority satellite. The article develops a wide range of simulations that modify the maneuver type, tracking antenna performance, antenna coverage, reconstruction method, filtering approach, and number of postmaneuver passes collected. The results determine the levels of error covariance necessary to perform successful maneuver reconstructions. Additionally, the results provide maneuver reconstruction confidence percentages based on the est...
CRYSTALLIZATION AND STRUCTURE FORMATION OF POLY(L-LACTIDE-CO-MESO-LACTIDE) RANDOM COPOLYMERS: A TIME-RESOLVED WIDE- AND SMALL-ANGLE X-RAY SCATTERING STUDY

Abstract Time-resolved synchrotron simultaneous wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) experiments were used to investigate the crystallization behavior and microstructure development of poly( l -lactide), PLLA, and two random copolymers containing l -lactide (predominately) and randomly placed R stereochemical defects. The general features of crystallization of PLLA and the copolymers are similar except that the copolymers crystallize much more slowly and to a lesser extent than PLLA, as expected. Lamellar thicknesses derived from SAXS experiments are in very good agreement with mean thicknesses determined in a tapping mode AFM study of the same materials. The reduction in lamellar thickness and crystallinity with increasing meso -lactide content supports significant exclusion of the R stereoisomer from crystalline lamellae. In a separate series of time-resolved WAXD/SAXS experiments, each (co)polymer was crystallized for a fixed time, then heated to above its melting point. The observed behavior suggests a model for crystallization of the copolymers in which thinner lamellae form between ‘primary’ lamellar stacks during crystallization, with an average lamellar thickness that decreases with increasing R stereoisomer content.
Practical Parallel Lempel-Ziv Factorization

In the age of big data, the need for efficient data compression algorithms has grown. A widely used data compression method is the Lempel-Ziv-77 (LZ77) method, being a subroutine in popular compression packages such as gzip and PKZIP. There has been a lot of recent effort on developing practical sequential algorithms for Lempel-Ziv factorization (equivalent to LZ77 compression), but research in practical parallel implementations has been less satisfactory. In this work, we present a simple work-efficient parallel algorithm for Lempel-Ziv factorization. We show theoretically that our algorithm requires linear work and runs in O(log2 n) time (randomized) for constant alphabets and O(nϵ) time (ϵ <; 1) for integer alphabets. We present experimental results showing that our algorithm is efficient and achieves good speedup with respect to the best sequential implementations of Lempel-Ziv factorization.
An analysis of paramedic verbal reports to physicians in the emergency department trauma room.

Objective. To measure the verbal communication between emergency medical technician-paramedics (EMT-Ps) and physicians in an emergency department trauma room (EDTR) before and after an educational intervention. Methods. Using a before-after design, we audio-recorded paramedic verbal trauma reports in a large EDTR over a 12-week period. Trained research assistants subsequently queried physicians about information from the paramedic report in a separate interview. Physician recall was quantified. Midway through the study, a web-based, educational intervention designed to enhance paramedic communication skills was administered to the three participating emergency medical services (EMS) systems. Physician recall of more severely injured trauma cases (red triage) was compared with their recall of less severely injured cases (yellow triage). Further comparisons were made between pre- and post-intervention physician recalls, and the extent to which physicians recalled three distinct categories of paramedic verba...
Abstract 1033: Inhibiting bladder cancer metastasis with a dietary supplement

INTRODUCTION AND OBJECTIVE: Hyaluronic acid (HA) and HYAL-1 hyaluronidase (HAase) family molecules are potential markers for BCa diagnosis and prognosis and promote tumor growth and metastasis. 4-Methylumbelliferone (4-MU) is an orally bioavailable dietary supplement that inhibits HA synthesis. Epithelial-to-mesenchymal transition (EMT) is the hallmark of invasion and metastasis. Since HA promotes tumor metastasis and EMT, we evaluated the expression of EMT markers in bladder tissues and antitumor effects of 4-MU in BCa models. METHODS: Quantitative PCR was used to measure mRNA expression of EMT genes (β-catenin, Twist, and Snail) in 66 bladder tissue specimens (27 normal; 39 tumor); follow-up: 26±4.3 months; median 20 months. The effect of 4-MU (40 - 120 µg/ml) on cell proliferation, apoptosis, intracellular signaling, and the expression of HA receptors and EMT genes were examined in BCa cell lines, 253J-Lung and HT1376. Effect of 4-MU on tumor growth was analyzed in subcutaneous xenografts. RESULTS: Among the EMT genes, Snail and Twist were differentially expressed in BCa tissues when compared to normal bladder (P 50 for HA synthesis, 4-MU inhibited proliferation (∼ 2.5-fold) and induced apoptosis (3-fold) in BCa cells. 4-MU induced caspase-8, -9 and -3 activation and up-regulation of Fas and FADD. 4-MU caused 4-10-fold downregulation of HA-receptors (CD44, RHAMM), and EMT promoters - β-catenin, Snail and Twist, but increased E-cadherin expression by 2-fold. In xenograft studies, 4-MU significantly decreased tumor growth (> 3-fold) when treatment was started either on the day of tumor cell injection or after tumors became palpable. No weight loss or serum or organ toxicity was observed in treated mice. Tumors showed reduced microvessel density (∼3-fold) and HA expression but increased TURNEL positive cells. CONCLUSION: This study shows that expression of EMT determinants correlates with clinical outcome. Furthermore, the non-toxic dietary supplement 4-MU has potent antitumor activity and reverses EMT. Support: R01 CA 123063-04 (VBL); R01 CA 72821-11 (VBL). Citation Format: Kelly T. Hoye, Travis Yates, David Alonzo, Vinata B. Lokeshwar. Inhibiting bladder cancer metastasis with a dietary supplement. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1033. doi:10.1158/1538-7445.AM2014-1033
Replies to commentators on Saving Truth From Paradox

Vann raises a number of important issues. One is over whether truth is basically just a logical notion. I take it to be clear that one purpose of a notion of truth is purely logical: to enable us to formulate generalizations that would otherwise be inexpressible, and to reason with them in appropriate ways. But is this its sole purpose, or even its central purpose? Many believe that truth has a more central role in linguistics and psychology, via truth-conditional approaches to meaning and content. This is a dispute on which I've written elsewhere: as Vann notes, my early writings took the view that the role of truth in truth-conditional semantics was primary, while my later writings have taken the view that truth is purely a logical notion. In writing the book I was determined not to discuss or take sides in that dispute, though I'm sure that at some points I express views that are more typical of those with the logical view than with the truth-conditional semantics view. I do see the book as providing a bit of indirect support for the logical view, in that if the paradoxes were to compel us to give up the transparency of truth (the equivalence between True( ) and A), that would probably seem more of an embarrassment for the logical view than for the truth-theoretical semantics view. (If 'true' were primarily a theoretical term in psychology and linguistics, then its not obeying expected laws wouldn't be that much of a shock: we're all used to discoveries that theoretical terms in science don't obey the naive principles that common sense lays
Direct Detection of the Thermodynamics and Structural Kinetics of a 2-Color SERCA Biosensor by Transient Time-Resolved FRET

We are investigating the structural dynamics of the calcium pump SERCA, using a 2-color biosensor and time-resolved FRET measurements. SERCA couples ATP hydrolysis to Ca2+ transport across the sarcoplasmic or endoplasmic reticulum membrane. Crystal structures suggest that SERCA structure changes dramatically during active Ca2+ transport, including large movements in the cytoplasmic N and A domains, coupled to more subtle changes in the transmembrane domain. However, there is little direct evidence showing how changes in SERCA structure coordinate, in solution and in cells, with individual steps in the pump's ATPase and Ca2+ transport cycles. Furthermore, SERCA is a viable therapeutic target for a host of diseases_heart failure, diabetes, and cancer_so it is important to understand how the ATPase and Ca2+ transport cycles are coupled to changes in the protein's structure. We are addressing these questions using a recombinant 2-color SERCA biosensor (RFP and GFP fused to the N and A domains) developed by Robia and coworkers for live-cell work. Here we use it in isolated membrane fragments to detect changes in SERCA structure in response to changes in Ca2+ and nucleotide concentrations, both at equilibrium and in the transient phase after rapid mixing. Our results: 1) reveal critical changes in the structural-dynamics of the SERCA cytoplasmic domains upon Ca2+ and nucleotide binding; and 2) suggest a structural-kinetic mechanism for Ca2+ activation of ATPase cycling with coordinated changes in the position of the cytoplasmic domains in association with sequential binding of Ca2+ ions and ATP. 3) These results also allow direct testing of x-ray crystal structure models in solution and in living cells and inform the discovery of novel SERCA modulators that directly target the pump's structural dynamics.
Gas chromatographic determination of residual levels of tert.-butanol from lyophilized liposomal formulations

The use of liposomal formulations is rapidly gaining popularity in pharmaceutical research and development. Their preparation often involves the use of organic solvents such as tert.-butanol to dissolve lipophilic lipids. To improve the physicochemical stability of the liposomes, lyophilizing the product is one of the best available means. A gas chromatographic method for the determination of tert.-butanol residual levels in lyophilized liposomes, employing sec.-butanol as internal standard, using a flame ionization detector (FID) detector and a cross-linked dimethylpolysiloxane capillary column, was developed. The method described is simple, sensitive, rugged, reliable and reproducible and requires less time than other reported methods for the quantitation of tert.-butanol; it also has pharmaceutical applications.
A second‐order ADI scheme for three‐dimensional parabolic differential equations

A second-order unconditionally stable ADI scheme has been developed for solving three-dimensional parabolic equations. This scheme reduces three-dimensional problems to a succession of one-dimensional problems. Further, the scheme is suitable for simulating fast transient phenomena. Numerical examples show that the scheme gives an accurate solution for the parabolic equation and converges rapidly to the steady state solution. © 1998 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 14:159–168, 1998
Delay and number of food reinforcers: Effects on choice and latencies.

Pigeons were given a choice between two identical-duration situations (terminal links of chain schedules). One terminal link of the choice pair provided two food deliveries, and the other provided five. The exact times of these food deliveries differed between the terminal links and were varied over conditions. A single response during the initial link gave immediate access to the corresponding terminal link. Forced trials, during which only one of the initial-link keys was lighted, were interspersed with choice trials during which both initial-link keys were lighted. Choice tended to favor whichever terminal link was correlated with the higher sum of the immediacies (i.e., the sum of the reciprocals of the delays to each of the reinforcers following the choice, with all delays measured from the choice). Latencies on forced trials and on choice trials also were related (negatively) to the sum of the immediacies. This correlation among response measures (choice and latencies) suggests that both measures are manifestations of the effect of conditioned reinforcement on response tendencies.
Thermal gradient effects in direct resistance heated metal matrix composites

Abstract In order to rapidly thermally cycle a metal matrix composite, the direct resistance heating method is often employed. There is concern about temperature gradients induced by the testing method; such gradients may not occur in applications. By performing a finite difference heat transfer calculation, it is shown that temperature gradients transverse to the specimen length are negligibly small, both for a typical metal fiber and also for a typical refractory fibre. This result allows us to consider the central hot-zone of the specimen as uniformly thermally cycled.
Perceptive agents and systems in virtual reality

1. THE VISION: A REALITY EMULATOR Imagine a computer-simulated world that approaches the realism and complexity of the real world. Inhabited by lifelike flora and fauna, this virtual world is populated by synthetic humans that look, move, and behave like natural humans. These autonomous agents are endowed with functional bodies and brains supporting motor control and locomotion, computational vision and audition, speech synthesis, natural language recognition, adaptive behavior, as well as cognitive skills, such as learning and reasoning. Such a Reality Emulator could be used in revolutionary ways and its impact across multiple scientific disciplines would be profound. Offering unprecedented predictive power, the Emulator would enable experimentation with complex and/or dangerous scenarios that cannot be attempted safely or repeatedly in real life. For example, it could simulate the reactions of crowds in crisis situations, such as terrorist bombings, in order to assess likely consequences and plan appropriate emergency responses. A realistic simulation of a fire in a virtual building occupied by virtual humans could help assess the visibility and accessibility of exits and plan rescue and evacuation procedures as a function of the location and type of fire, smoke dispersal, ventilation, and so on. A less dramatic scenario would be the realistic simulation of automated CCD surveillance cameras directed in the lobbies and concourses of a busy train station or airport, in order to facilitate the development and testing of a distributed, vision-based human surveillance system capable of detecting suspicious behavior. Although VR’s holy grail may be a real-time, interactive synthetic reality of the sort portrayed in the motion picture “The Matrix”, by no means need our Emulator run in real time for it to be of immediate value in the sorts of applications described above. Rather, the fidelity and usefulness of such simulations is ultimately dependent on a detailed modeling of the abilities and limitations of human bodies, perception systems, and mental processes under real-world conditions. A non-real-time Reality Emulator of the sort described above is well within reach if one could deploy a web-based, distributed implementation infrastructure that would elicit the participation of a broad, multidisciplinary community of researchers.
Central exclusive production issue: Introduction

I give a brief introduction to central exclusive production in hadron–hadron collisions, the subject of this special issue of the International Journal of Modern Physics A.
Realizing Benefits from Enterprise Resource Planning: Does Strategic Focus Matter?

A key driver of the recent wave of enterprise resource planning (ERP) implementations was the assumption that the integration of business information would provide firms with a competitive advantage, yet concrete business benefits have been uneven across adopting firms. A possible explanation is that although the resource-based view holds that competitive advantage is derived from inimitable resources, ERP software has become a commodity. Socio-technical theory suggests that internal organizational resources based on a foundation of ERP technology may be the true drivers of ERP benefits. A firm's strategic configuration is posited to influence the portfolio of organizational competencies available to leverage the benefits of integrated business information, and a number of hypotheses are developed based on the notion that firms with different strategic objectives will realize different operational benefits from the adoption of ERP systems. Survey data from North American manufacturing firms that have implemented ERP systems demonstrate that ERP adopters seeking operational performance improvements are likely to realize these benefits. On the other hand, those seeking external market and supply chain performance improvements must first establish a foundation of internal operational performance improvements before customer satisfaction and supply chain benefits can be realized.
Calculating with acyclic and cyclic lists

Abstract We use a relational model of pointer structures to calculate a number of standard algorithms on singly linked lists, both acyclic and cyclic. This shows that our techniques are not just useful for tree-like structures, but apply to general pointer structures as well.
Cardiorespiratory response to exercise after the Fontan operation: a serial study.

Abstract Objectives. The purpose of this study was to assess whether there is deterioration of aerobic capacity over time after the Fontan operation in individual patients. Background. We previously observed that maximal aerobic capacity after the Fontan operation was lower in older patients than in younger patients. It was unclear whether this represented a decrease in aerobic capacity with time after operation or was a function of studying patients of different ages at different times postoperatively. Methods. All patients who had more than one postoperative exercise study were included. There were 25 patients (19 male, 6 female), aged 3.8 to 39 years at the time of the operation. The first exercise test was performed, on average, 2.2 years after the Fontan operation, and the last exercise test was performed, on average, 5.9 years (range 1.8 to 13) after the operation. In 11 patients, coronary sinus drainage was left on the pulmonary venous side. Five patients had had a previous Glenn operation. Exercise was performed to exhaustion with use of a 3-min incremental cycle protocol. Results. Exercise duration, oxygen uptake, blood pressure, respiratory rate, minute ventilation, pulmonary blood low index, exercise factor, ST-T wave changes and the prevalence of arrhythmias were similar during the first and last tests. Exercise systemic arterial blood oxygen saturation decreased from the first to the last postoperative test (p Conclusions. In this select group of patients, exercise tolerance remained relatively unchanged over the range of 13 years after the Fontan operation. Heart rate at rest and during maximal exercise decreased more than predicted for age in older patients. A small but significant progressive decrease in systemic arterial blood oxygen saturation was found. The former might represent abnormal sinus node function in patients with functional single ventricle, and the latter might represent a tendency toward development of abnormal ventilation/perfusion patterns resulting from the development of small pulmonary arteriovenous fistulas or an effect of position of the coronary sinus postoperatively.
Constructions of representations of o(2 n + 1, C) that imply Molev and Reiner-Stanton lattices are strongly Sperner

Two infinite families of distributive lattices parameterized by positive integers n and k are considered. The first family of lattices, here denoted LRSB(k,2n), was introduced by Reiner and Stanton (J. Algebraic Combin. 7 (1998) 91) as the distributive lattices Good(k,2n) of certain partitions. There, Reiner and Stanton showed that these lattices are rank symmetric and rank unimodal and conjectured that they are strongly Sperner. The second family of lattices introduced here is denoted LMolB(k, 2n) because of its connection to certain representation constructions of the odd orthogonal Lie algebras obtained by Molev (J. Phys. A 33 (2000) 4143). For fixed n and k, the two lattices have the same rank generating function, but the lattices are isomorphic as posets if and only if k = 1. In this paper, the lattices LRSB(k,2n) and LMolB(k,2n) are used to produce two different constructions of the irreducible representation of the odd orthogonal Lie algebra o(2n + 1, C) isomorphic to the largest irreducible component in the kth symmetric power of the defining representation of o(2n + 1, C). Constructions of the analogous infinite family of irreducible representations of G2 are obtained as a special case. These constructions use the elements of the lattices to index bases for the representing spaces, and explicit formulas for the matrix entries of the representing matrices for certain Lie algebra generators are given. These constructions together with a result of Proctor imply that both lattices are rank symmetric, rank unimodal, and strongly Sperner.
Bladder Oxidative Stress in Sleep Apnea Contributes to Detrusor Instability and Nocturia

Purpose: Obstructive sleep apnea is associated with voiding symptoms in humans and animals, and yet its effects on the urinary tract are poorly understood. We examined bladder structure and function, markers of oxidative damage and the redox survival pathway in a rat model of obstructive sleep apnea to identify changes.Materials and Methods: To model obstructive sleep apnea we used a rat oxycycler system to create cyclical interruption in breathing oxygen, thereby producing intermittent hypoxemia. Male Sprague Dawley® rats were divided into an obstructive sleep apnea, a sham treated and a control group of 8 each. After 8-week exposure to obstructive sleep apnea conditions we assessed daytime and nighttime rat voiding behavior in metabolic cages. Cystometrograms were done and bladder tissue was processed for biochemical assays, enzyme-linked immunosorbent assay and transmission electron microscopy.Results: Increased urinary frequency and total urine output developed in rats exposed to obstructive sleep apn...
Open Biopsy for Chronic Diffuse Infiltrative Lung Disease: Clinical, Roentgenographic, and Physiological Correlations in 502 Patients

Clinical, physiological, roentgenographic, and histological data concerning 502 patients who had open biopsy for chronic "interstitial" lung disease were reviewed. Mortality was 0.3%, the rate of complications was 2.5%, and the diagnostic yield was 92.2%. A modified Chamberlain approach in the second interspace is preferred for easy access to all lobes and mediastinum. Brief tube drainage is mandatory. Atelectasis and hemorrhage in the specimen are prevented by avoiding palpation and clamps, by delineating the wedge during full inflation, and by instant fixation. Customary biopsies of the tip of the lingula or middle lobe are avoided because these are common sites of inflammation, scarring, and passive congestion. Often, the most abnormal regions are biopsied apparently to aid the pathologist. Such selection has been the most important cause of meaningless histological findings and poor pathological, physiological, and roentgenographic correlations because these regions usually show end-stage disease of unrecognizable origin. Average lung is more likely to show an active and recognizable process.
Equilibria in open common value auctions

Abstract A sufficient condition for uniqueness of Nash equilibrium in second-price, common value auctions is identified. We establish that there exists a continuum of equilibria in irrevocable exit, common value auctions. For the case of two bidders, we provide plausible sufficient conditions under which the expected seller revenue is maximized at the symmetric equilibrium. An example in which the auctioneer's revenue at the symmetric equilibrium in a second-price auction is strictly greater than the revenue at many asymmetric equilibria in the corresponding irrevocable exit auction is provided.
Intermittent Electron Transfer Activity From Single CdSe/ZnS Quantum Dots

Electron transfer activity from excited single CdSe/ZnS core/shell quantum dots (QDs) to adsorbed Fluorescein 27 was studied by single QD fluorescence spectroscopy. In comparison with QDs, the QD-acceptor complexes showed a shorter average and broader distribution of QD emission lifetimes due to electron transfer to adsorbates. Large fluctuation of lifetimes in single QD/dye complexes was observed, indicating intermittent electron transfer activity from QDs.
Role of Organic and Inorganic Reactions in Development of Secondary Porosity in Sandstones: ABSTRACT

The development of secondary porosity in many sandstones is the result of aluminosilicate and/or carbonate dissolution. The dissolution of aluminosilicates and creation of secondary porosity is a problem of aluminum mobility. Our experimental data demonstrate that it is possible to increase significantly the mobility of aluminum and to transport it as an organic complex in aliphatic acid solutions. The same aliphatic acid solutions have the capability of destroying carbonate cements and debris. Carothers and Kaharka have shown that concentrations of aliphatic acid anions range up to 5,000 ppm over the temperature range 80 to 200°C in some oil field formation waters. Our experiments show that acetic acid solutions at the same concentrations and over the same temperature range can increase the solubility of aluminum by a half an order of magnitude, whereas oxalic acid solutions increase the solubility of aluminum by an order of magnitude. The textural relations observed in the experiments are identical to those observed in sandstones containing secondary porosity as a result of aluminosilicate dissolution. A natural consequence of the burial of sedimentary prisms is the maturation of organic material. These maturation reactions result in the evolution of significant amounts of organic acids and carbon dioxide. The experiments suggest that the development of secondary porosity in a sandstone as a result of aluminosilicate or carbonate dissolution is the natural consequence of the interaction of organic and inorganic reactions during progressive diagenesis. The degree to which secondary porosity develops depends on the ratio of organic to inorganic matter, the sequence, rates and magnitude of diagenetic reactions, fluid flux, and sand/shale geometry. End_of_Article - Last_Page 635------------
Common statistical concerns in clinical trials

Statistics are an integral part of clinical trials. Elements of statistics span clinical trial design, data monitoring, analyses, and reporting. A solid understanding of statistical concepts by clinicians improves the comprehension and the resulting quality of clinical trials. This manuscript outlines common statistical concerns in clinical trials that are important for clinicians to understand.
Symbiotic bacteria contribute to innate immune defenses of the threatened mountain yellow-legged frog, Rana muscosa

Symbiotic microorganisms influence health and disease and may contribute to the innate immune defenses of amphibians. The mountain yellow-legged frog, Rana muscosa, is currently undergoing unprecedented population declines. One cause of recent declines is the pathogenic chytrid fungus, Batrachochytrium dendrobatidis (Bd). Skin swabs for detection of Bd, skin peptide secretions, and symbiotic skin bacteria were collected from 70 adult R. muscosa from two populations designated “Sixty Lake” and “Conness” in 2004–2005. The Conness population has persisted with the presence of Bd for at least 6 years whereas the Sixty Lake population is newly infected and declining. Of the frogs sampled at Conness, 67.5% were infected; whereas 96.7% of the Sixty Lake frogs were infected. Sixty Lake frogs were also more intensely infected than frogs at Conness. We isolated symbiotic bacteria that may contribute to immune defense. A significantly greater proportion of individuals with at least one anti-Bd bacterial species present were found at Conness (85%) than at Sixty Lake (62%). We observed no apparent differences in total skin peptides recovered; however, peptide mixtures from frogs at Sixty Lake showed better growth inhibitory activity against Bd than peptides from frogs at Conness. By MALDI-TOF MS analysis, there were no differences between the two populations in the previously described antimicrobial peptides (ranatuerin-2Ma, ranatuerin-2Mb, and temporin-1M). Antimicrobial skin peptides are only one factor in the resistance of R. muscosa to Bd infection. We suggest that symbiotic bacteria with the ability to persist in the presence of mucosal peptides may inhibit infection and colonization of the skin by Bd and increase the effectiveness of innate defense mechanisms in the skin.
Kleo: A Bootstrapping Learning-by-Reading System

KLEO is a bootstrapping learning-by-reading system that builds a knowledge base in a fully automated way by reading texts for a domain. KLEO’s initial knowledge base is a small knowledge base that consists of domain independent knowledge and KLEOexpands the knowledge base with the information extracted from texts. A key facility in KLEO is knowledge integration which combines new information gleaned from individual sentences of the texts, along with prior knowledge, to form a comprehensive and computationally useful knowledge base. This paper introduces the architecture of KLEO, especially the knowledge integration facility, and presents our evaluation plan. The knowledge acquisition bottleneck has been the major obstacle to building large-scale knowledge bases. Despite enormous past efforts, it is still costly and tedious to build knowledge bases manually. As a solution to this problem, a new approach has been gaining much attention due to the advance of natural language processing and the proliferation of texts on the Internet. The approach is to construct a knowledge base with knowledge extracted from texts. KLEO 1 is a such Learning-by-Readingsystem which op