cssi/SciSciGPT-SciSciNet huggingface dataset:
Mental model progression in learning the electron transport chain: effects of instructional strategies and cognitive flexibility

This study investigated the effect of two instructional strategies, segmented and holistic, on the progression over time of learners’ mental models toward that of an expert with the moderator of cognitive flexibility. Sixty-four juniors and seniors in a college metabolism course were randomly assigned to one of the two strategies for instruction on the electron transport chain. The data were analyzed with a repeated measures general linear model. Mental models progressed significantly for both strategies (p < .001), and a significant interaction was found between cognitive flexibility and instructional strategy on mental model progression (p = .02). The segmented strategy was superior for learners with higher cognitive flexibility but inferior to the holistic strategy for lower cognitive flexibility learners. Results have important implications for differentiating instruction on the basis of learner characteristics.
Unsupervised segmentation of spaceborne passive radar images

Abstract Remote sensing over a wide area, such as a rainforest or arctic region, is often done by segmenting multispectral images from a spaceborne passive radar. In such applications, the number and types of segmented regions are often unknown, and boundaries between segmented regions are often fuzzy. An unsupervised segmentation approach utilizing a fuzzy clustering algorithm is presented in this paper, and applied to segmentation of images of arctic regions. The steps to improving processing speed, including preprocessing and reduction of feature space, are also presented. The experimental results with images from SSM/I sensor show that segmented regions found by this fuzzy clustering approach are stable and that the seasonal change can be monitored from the clustered results.
Broadening of Highly Excited Atomic Levels in an Atmosphere of Alkali-Metal Atoms

Interactions between a highly excited atom and another atom in the ground state with nonzero electron affinity lead to a splitting of highly excited levels. This situation provides a mechanism which modifies spectral lines of a Rydberg series. Electronic transitions between components of the quasi molecular level due to interatomic motion are analyzed on the basis of the adiabatic theory. The width of a spectral line near the edge of the series is expressed in terms of the electron affinity of the perturbing atom and other calculable quantities. Comparison of the present theoretical result and experimental data for K and Cs shows that this mechanism is as significant for linewidths as the Fermi process for line shifts.
Changes in strawberry anthocyanins and other polyphenols in response to carbon dioxide treatments

Carbon dioxide-enriched atmospheres are used to reduce the incidence and severity of decay and to extend the postharvest life of strawberries. The influence of CO2 on the postharvest quality parameters of strawberries, particularly the stability of anthocyanins and other phenolic compounds, was investigated. Freshly harvested strawberries were placed in jars ventilated continuously with air or air enriched with 10%, 20%, or 40% CO2 at 5 °C for 10 days. Samples were taken initially, and after 5 and 10 days of storage, and color (L* a* b* color space), pH, TA, TSS, and firmness were measured. Anthocyanins and other phenolics were analyzed by HPLC. Elevated CO2 degraded internal color while air-treated fruit remained red. Internal and external tissues differed in composition and concentration of phenolic compounds. CO2had a minimal effect on the anthocyanin content of external tissues but induced a remarkable decrease in anthocyanin content of internal tissues. Factors, such as pH and copigmentation, that could explain this degradation are discussed.
Pinch Oscillations in Electron-Hole Plasmas. II. Experiment

Most of the measurements concern the spontaneous pinch oscillations that occur when the current exceeds a threshold value. Some properties of oscillations driven at subthreshold conditions are described also. The oscillations are characterized by several parameters: threshold current, amplitude, frequency, and wavelength. The dependency of the spontaneous oscillation properties on current, temperature, and time are reported. An applied longitudinal magnetic field has remarkable effects on the oscillations. In particular, the oscillations are stabilized at a critical magnetic field which depends on the current. The variations of the oscillation amplitude and the mode type with applied magnetic field are also shown. At subthreshold conditions, a driven pinch ($m=0$) oscillation can be readily launched in a pinched plasma; its spatial growth is reported. This type of oscillation is attenuated strongly by the application of a longitudinal magnetic field exceeding 50 G. In a prepinched plasma (low current levels), the driven helical mode ($m=1$) oscillation can be made to grow, if the appropriate magnetic field is applied. The results are divided into two groups for discussion, those results explained by the theory presented in the preceding paper and those not formally explained.
Group-based Microcredit & Emergent Inequality in Social Capital: Why Socio-religious Composition Matters

Microcredit groups have a worldwide presence today due to the popularity of microfinance programs as a development intervention. During the period of microcredit’s rise, development discourse and research has also seen increasing attention focused on “social capital.” This paper is an attempt to identify mechanisms linking religious composition of microcredit groups and their social capital, defined in this paper as the capacity for collective action of the kind required for achieving conventional public goods and “participatory public goods” (those general benefits that can be attained solely through voluntary cooperation/ mobilization). This post-factum identification is based on analyzing qualitative data from real-life cases in India of collective action and sanctioning (to protect women) undertaken by Hindu microcredit groups, and the absence of collective action in Muslim microcredit groups. The paper makes a theoretical contribution by furthering our understanding of emergent inequality in social capital, i.e., unevenness in the way social capital resources and benefits accumulate among different communities and groups of people.
A Strategy for Evaluating the NSF Comprehensive Program for Teacher Education

Afl:;TFACT TIris document presents the design ot an evaluation study c-)r. the Program of Comprehensive Grant for Teacher Education which in i.unded by the National Science Foundation (NSF). The main concerns et the evaluation' were the need to provide context intormation to individual-project directorand to develop a summative strategy for the national program. A total of 17 in:Aruments were selected to collect a variety of cognitive and affect-ive: data for bot !-;cience and mathematics projects from students, teachers and aJministrators. Approximately one-half ot
Genomic structure of chromosome 17 deletions in BRCA1-associated ovarian cancers

The aim of this study was to determine the genomic structure of the deletions on chromosome 17 in ovarian carcinomas from women with inherited BRCA1 mutations. Normal and tumor DNA from 14 ovarian tumors associated with inherited BRCA1 mutations were extracted and tested for loss of heterozygosity (LOH) at microsatellite markers along chromosome 17. Finer mapping using more microsatellite markers and single nucleotide polymorphisms helped further define the LOH margins. The genomic repeated elements within the LOH breakpoint regions were identified using the University of California Santa Cruz Genome Database, and the frequencies were compared to regions of equal GC percentages across the genome. Of the 14 ovarian tumors, 12 showed LOH of the entire chromosome 17. The other two tumors lost the distal end of the 17q arm. The breakpoints of these two tumors occurred in regions with significantly high frequencies of short interspersed nuclear elements (SINE), specifically Alu elements. Ovarian tumors of high grade and stage have large regions of LOH along chromosome 17, with most tumors showing loss of the entire chromosome. In those tumors with retention of part of chromosome 17, LOH margins suggest that a high Alu content may have a role in the deletions.
Evaluating cell matrix mechanics using an integrated nonlinear optical tweezer-confocal imaging system

ABSTRACT Biomechanics plays a central role in breast epithelial morphogenesis. In this study we have used 3D cultures in which normal breast epithelial cells are able to organize into rounde d acini and tubular ducts, the main structures found in the breast tissue. We have identified fiber organization as a main determinant of ductal organization. While bulk rheological properties of the matrix seem to play a negligible role in determining the proportion of acini versus ducts, local changes may be pivotal in shape determination. As such, the ability to make microscale rheology measurements coupled with simultaneous optical imaging in 3D cultures can be critical to assess the biomechanical factors underlying epithelial morphogenesis. This paper describes the inclusion of optical tweezers based microrheology in a microscope that had been designed for nonlinear optical imaging of collagen networks in ECM. We propose two microrheology methods and show preliminary results using a gelatin hydrogel and collagen/Matrigel 3D cultures containing mammary gland epithelial cells. Keywords: Collagen, optical tweezer, confocal, extracellular matrix, mechanics, microrheology, breast epithelial morphogenesis
The customary international law of transboundary fresh waters

Drawing upon the experience of century, nations have constructed a customary international law for transboundary fresh water resources built around the principle of equitable utilisation. The earliest complete formulation of this body of law as the Helsinki Rules on the Uses of International Rivers of the International Law Association of 1966. Like all customary law, this body of international Law retains flexibility by being vague while allowing only for relatively primitive enforcement mechanisms. In an effort to improve things, the United Nations, working initially through the International Law Commission, drafted a convention to codify the customary law. Even before that treaty enters into force, it has become the most cogent summary of the relevant customary international law. Despite certain advances over the customary law in the terms of the treaty, it ultimately fails adequately to integrate the environmental or ecological concerns now emerging in international law into the older body of international water law. This need suggests that a revised Helsinki Rules could serve to complete the unfinished task of adapting international water law to the needs of the twenty-first century.
Aneuploidy and chromosomal instability: a vicious cycle driving cellular evolution and cancer genome chaos

Aneuploidy and chromosomal instability frequently co-exist, and aneuploidy is recognized as a direct outcome of chromosomal instability. However, chromosomal instability is widely viewed as a consequence of mutations in genes involved in DNA replication, chromosome segregation, and cell cycle checkpoints. Telomere attrition and presence of extra centrosomes have also been recognized as causative for errors in genomic transmission. Here, we examine recent studies suggesting that aneuploidy itself can be responsible for the procreation of chromosomal instability. Evidence from both yeast and mammalian experimental models suggests that changes in chromosome copy number can cause changes in dosage of the products of many genes located on aneuploid chromosomes. These effects on gene expression can alter the balanced stoichiometry of various protein complexes, causing perturbations of their functions. Therefore, phenotypic consequences of aneuploidy will include chromosomal instability if the balanced stoichiometry of protein machineries responsible for accurate chromosome segregation is affected enough to perturb the function. The degree of chromosomal instability will depend on specific karyotypic changes, which may be due to dosage imbalances of specific genes or lack of scaling between chromosome segregation load and the capacity of the mitotic system. We propose that the relationship between aneuploidy and chromosomal instability can be envisioned as a “vicious cycle,” where aneuploidy potentiates chromosomal instability leading to further karyotype diversity in the affected population.
The 1987—1988 Taulbee survey

The Computing Research Board's 1987-1988 Taulbee Survey includes the latest statistics on production and employment of Ph.D.'s and faculty in computer science and engineering. Included also are departments offering Ph.D.'s in computer engineering.
A Biphasic Memory Curve in the Chambered Nautilus, Nautilus Pompilius L. (Cephalopoda: Nautiloidea)

SUMMARY Cephalopods are an exceptional taxon for examining the competing influences of ecology and evolutionary history on brain and behaviour. Coleoid cephalopods (octopuses, cuttlefishes and squids) have evolved specialised brains containing dedicated learning and memory centres, and rely on plastic behaviours to hunt prey effectively and communicate intricate visual displays. Their closest living relative, the primitive nautilus, is the sole remnant of an ancient lineage that has persisted since the Cambrian. Nautilus brains are the simplest among the extant cephalopods, and the absence of dedicated learning and memory regions may represent an ancestral condition. It is assumed that the absence of these regions should limit memory storage and recall in nautilus, but this assumption has never been tested. Here we describe the first evidence of learning and memory in chambered nautilus ( Nautilus pompilius ). Using a Pavlovian conditioning paradigm, we demonstrate that chambered nautilus exhibits temporally separated short- and long-term memory stores, producing a characteristic biphasic memory curve similar to that of cuttlefishes. Short-term memory persisted for less than 1 h post-training, whereas long-term memory was expressed between 6 and 24 h after training. Despite lacking the dedicated neural regions that support learning and memory in all other extant cephalopods, nautilus expressed a similar memory profile to coleoids. Thus the absence of these regions in the nautilus brain does not appear to limit memory expression, as hypothesised. Our results provide valuable insights into the evolution of neural structures supporting memory.
Complications of Computer-Aided-Design/Computer-Aided-Machining-Guided (NobelGuide™) Surgical Implant Placement: An Evaluation of Early Clinical Results

Purpose: The aim of this study was to evaluate early clinical results of computer-aided design (CAD)/computer-aided machining (CAM)-guided surgical implant placement (NobelGuide™, Nobel Biocare, Yorba Linda, CA, USA) with focus on surgical and/or prosthetic complications, management, and prevention. Materials and Methods: Thirteen patients rehabilitated between March 2003 and October 2006 with CAD/CAM-guided dental implants and immediate loading (NobelGuide, Nobel Biocare) were evaluated. The treatment planning and procedures were carried out in accordance to the system protocol. The complications encountered in this case series were classified and assessed according to early (planning and procedural – surgical; prosthetic) and late complications (surgical; prosthetic). Results: The prosthetic complications outnumbered surgical complications both in the early and late treatment phases. The main early surgical complication was bony interference that prevented complete seating of the prostheses. Most of the late surgical complications were implant failures with an overall failure rate of 9%. Fracture of the carbon fiber framework prosthesis was the main late prosthetic complication. Conclusions: The NobelGuide system is a reliable treatment modality, but not without its complications. Strict adherence to the system protocol is the key prevention of complications.
Extremely Electron-Rich, Boron-Functionalized, Icosahedral Carborane-Based Phosphinoboranes

We have prepared the first examples of B9-connected trivalent aryl and alkyl phosphinoborane species via Pd-catalyzed phosphination of 9-iodo-meta-carborane. Our studies highlight the unique electronic features of the B9-connected meta-carboranyl moiety as compared to its C1-based analogue. This work suggests that the B9-functionalized meta-carboranyl substituent in these ligands exhibits more electron-releasing character than any other known carbon-based substituent, ultimately laying the foundation for a new class of phosphine ligands with extremely electron-rich character.
Temperament and home environment characteristics as causal factors in the early development of childhood psychopathology

Abstract Results are reported of a 2-year prospective, longitudinal study of young children representing a general population sample. Temperament and home environment characteristics measured at age 2 and again at 3 are used to predict behavioral problems at age 3. The findings indicate that the temperament characteristics of poor adaptability and high intensity of emotional expression more powerfully predict behavior problems than do indices of the interpersonal and material home environment. Beyond the influence of temperament, marital discord operates rather selectively in boys to heighten the risk for a poor outcome.
Electron tunneling rates between atoms and surfaces covered by dielectric films

Abstract Using the complex scaling method, we have investigated how the energy shift and broadening of atomic levels near metal surfaces is modified when thin dielectric films are adsorbed on the surface. The calculation shows that dielectric films can introduce a significant tunneling barrier which can drastically reduce the widths of the atomic levels. Also, the atomic level shift can be strongly modified. Near the metal/film and film/vacuum interface non-image-like shifts occur which can be sufficiently strong to alter the charge transfer.
GABAA receptor modulation in dorsal root ganglia in vivo affects chronic pain after nerve injury

Neuropathic pain (NPP) due to sensory nerve injury is, in part, the result of peripheral sensitization leading to a long-lasting increase in synaptic plasticity in the spinal dorsal horn. Thus, activation of GABA-mediated inhibitory inputs from sensory neurons could be beneficial in the alleviation of NPP symptoms. Dorsal root ganglia (DRG) conduct painful stimulation from the periphery to the spinal cord. Long-lasting down-regulation in GABA tone or sensitivity in DRG neurons has been reported in animals with neuropathy. To determine the function of GABA in DRG in the development of NPP, we examined how the acute pharmacological GABA(A)-receptor modulation of L5 DRG in vivo affects the development of NPP in rats with crush injury to the sciatic nerve. Direct application of muscimol and gaboxadol, GABA(A) agonists, to L5 DRG immediately after injury induced dose-dependent alleviation, whereas bicuculline and picrotoxin, GABA(A) antagonists, worsened NPP postaxonal injury. The pain-alleviating effects of muscimol and gaboxadol were blocked by bicuculline. Muscimol, applied at the time of injury, caused complete and long-lasting abolishment of NPP development. However, when muscimol was applied after NPP had already developed, its pain-alleviating effect, although significant, was short-lived. Using a fluorescent tracer, sodium fluorescein, we confirmed that local DRG application results in minimal spread into the corresponding dorsal horn of the ipsilateral spinal cord. GABA(A) receptors in DRG are important in the development of NPP after peripheral nerve injury, making timely exogenous GABAergic manipulation at the DRG level a potentially useful therapeutic modality.
A Convenient Synthesis of 1-Aryl-Δ2-1,2,4-Triazolin-5-Ones From Arylhydrazines

Abstract 1-Aryl-1,2,4-triazolin-5-ones are prepared from arylhydrazones of α-keto acids by treatment with diphenylphosphoryl azide.
The effect of in situ laser annealing on laser ablation deposited garnet films

Abstract We have studied the influence of in situ laser annealing on the growth of garnet films by pulsed laser deposition. The KrF excimer laser that is used for ablation also provides in situ laser irradiation to the film with an energy density in the range 60–130 mJ/cm 2 . Results show that laser annealing helps crystallize the film and affects the film microstructure dramatically depending upon the annealing laser fluence. When using a substrate temperature of 570°C, a laser irradiation at a low fluence of 60 mJ/cm 2 induces crystallization and the film consists of densely packed grains. At 100 mJ/cm 2 , the film is partially melted resulting in a very smooth film surface and a decrease in crystallization. Ablation starts to occur at an energy density of 130 mJ/cm 2 for these garnet films. We also show that such laser annealing does not lead to a significant reduction in the required substrate temperature for crystallization even though the transient temperature rise can be high enough to melt the film.
Performance of a CMOS Schmitt trigger at liquid nitrogen temperature

Abstract The performance of a typical CMOS Schmitt trigger integrated circuit has been studied at liquid nitrogen temperature. It is shown that the Schmitt trigger parameters V + , V − , ΔV + and ΔV − change at lower temperatures due to a change in the MOSFET's threshold voltage. It has been observed that the forward trigger voltage V + shifts toward the right and the reverse trigger voltage V − shifts toward the left at liquid nitrogen temperature with respect to their corresponding room temperature values. This behaviour results in an increase in forward and reverse hysteresis ranges ΔV + and ΔV − of the Schmitt trigger. Experimental results are found to be in good agreement with theory.
Inversions in ranking data

In this note we prove a conjecture of P. McCullagh that inversions provide a basis for subset effects in ranking data.
Neural Processing of Gravito-Inertial Cues in Humans. IV. Influence of Visual Rotational Cues During Roll Optokinetic Stimuli

Sensory systems often provide ambiguous information. For example, otolith organs measure gravito-inertial force (GIF), the sum of gravitational force and inertial force due to linear acceleration. ...
Bipartite graphs with cycles of all even lengths

Let G = (X, Y, E) be a bipartite graph with X = Y = n. Chvatal gave a condition on the vertex degrees of X and Y which implies that G contains a Hamiltonian cycle. It is proved here that this condition also implies that G contains cycles of every even length when n > 3.
Evaluation of lymphadenectomy in patients receiving neoadjuvant radiotherapy for rectal adenocarcinoma.

Background Accurate pathologic staging has been shown to correlate with outcome in rectal cancer. Because the exact number of examined lymph nodes (LNs) may vary with preoperative therapies, our objective was to measure the impact of neoadjuvant radiation on LN number for rectal adenocarcinoma.
Nonfinitely Based Pseudovarieties and Inherently Nonfinitely Based Varieties

An algebra is a set together with a finite number of finitary operations. The arities of the operations define its type . The variety generated by an algebra A is the class of all algebras of the same type as A which satisfy at least every identity which A does. An equivalent description of this variety is that it is the smallest class containing A which is closed under homomorphisms, subalgebras, and products. A set of identities of A from which every identity of A can be derived in the equational logic constitutes a basis for this variety. The variety is finitely based if it has a finite basis. Equivalently, the algebra A is said to be finitely based. See [2] for background on equational logic and varieties. For the remainder of this note, A will always denote a finite algebra. The p~eudovariety generated by A is the smallest class containing A and closed under homomorphisms, subalgebras, and finite products. Since A generates a locally finite variety, one can show that the pseudovariety generated by A consists of all finite algebras in the variety generated by A. This pseudovariety is finitely based if it consists of the finite algebras of some finitely based variety. Clearly, if A is finitely based then it generates a finitely based pseudovariety. But if A is nonfinitely based, does it necessarily generate a nonfinitely based pseudovariety? Although this general question is open, it has been answered affirmatively by Sapir when A is a semigroup [6,7]. In [3] it is shown that if A, of arbitrary type, has a property called w-bounded (which insures that A is nonfinitely based), then it will generate a nonfinitely based pseudovariety. We will give two examples of w-bounded algebras; Perkins' semigroup and Lyndon's groupoid. Is every nonfinitely based A necessarily w-bounded? If so, then the previous question could be answered in the affirmative as well. A locally finite variety V is inherently nonfinitely based if every locally finite variety W D V is nonfinitely based. In particular, a finite algebra is called inherently nonfinitely based if it does not belong to a locally finite variety which is finitely based. Sapir [6] has shown that Perkins' semigroup has this property, while Bajusz, McNulty, and Szendrei have shown that Lyndon's groupoid does not [1]. Unlike w-bounded algebras, there is no known reason why an inherently nonfinitely based A could not generate a finitely based pseudovariety. We will show that every nonfinitely based finite algebra is either inherently nonfinitely based or w-bounded. Perkins' semigroup falls in the intersection of these classes while Lyndon's groupoid must be w-bounded since it is not inherently nonfinitely based.
Vascular endothelial growth factor‐targeted therapy in metastatic renal cell carcinoma

Inactivation of the von Hippel-Lindau tumor suppressor gene in most sporadic renal cell carcinoma (RCC) tumors leads to a fundamental reliance on elements of this pathway, namely, the potent proangiogenic factor, vascular endothelial growth factor (VEGF). Thus, VEGF-targeted therapeutics have undergone extensive clinical testing in RCC. Approaches to bind circulating VEGF protein (eg, bevacizumab) and small molecule inhibitors of the receptor on which the VEGF ligand binds (eg, sunitinib, sorafenib, axitinib, and pazopanib) have been tested. Robust clinical effects have been observed, including high objective response rates, prolonged progression-free survival, and evidence of long overall survival for patients with metastatic RCC patients who are treated with these agents. Future directions include investigation of combination and sequenced therapy, elucidation of mechanisms of response and resistance, and exploration of the effect of these agents in other disease settings.
Folded gate&#8212;A novel logic gate structure

We propose a new logic gate structure which consists of two semiconducting layers separated by an insulator. The input electrode is a rectifying contact to the top conducting layer which acts as a channel of a switching field-effect transistor. The bottom conductive layer serves as a load. The conducting layers are connected and capacitively coupled. The top layer acts as a gate for the load element whereas the bottom layer acts as a second gate for the top conductive channel. This "folded" gate is a majority-carrier device which may be implemented using different technologies and materials. It allows a CMOS-like operation with a very low power consumption in the stable states, speed comparable or higher then the speed of conventional direct-coupled field-effect transistor logic (DCFL), and a larger voltage swing.
Accurate reduced-order models for a simple rotor blade model using nonlinear normal modes

Herein, a novel reduction procedure is applied to a simplified rotor blade model, yielding a single degree of freedom reduced-order model with exceptional accuracy. This approach is advantageous, as the nonlinear interactions present in rotorcraft systems often necessitate large-scale models when traditional finite-element or linear modal expansion methods are applied. These large models are cumbersome and may incur considerable computational cost for accurate simulations. The proposed procedure may ease this computational burden by producing a reduced set of governing equations which correctly account for the nonlinear behavior of the original system. This reduction is achieved through a Galerkin-based solution for the invariant manifold which governs the nonlinear normal mode of interest for the rotor blade. This solution method is primarily numerical, and is much more accurate than the previous asymptotic approaches. Results are shown for an example of a nine meter blade, for which peak to peak blade amplitudes of one meter can be accurately captured using a single nonlinear normal mode. The reduced-order, single degree of freedom model dynamics are shown to be nearly indistinguishable from those of a reference system which possesses 18 degrees of freedom. Though the blade model used here is quite simple in terms of geometry, the reduction method is easily applicable to much more general blade models, as well as to other nonlinear structural systems.
Furadroxyl as a Growth Stimulant in Broiler Diets

Abstract DODD and Stillman (1944) prepared a series of furan derivatives and tested them for antibacterial activity, discovering that a nitro group substituted for hydrogen in the number 5 position of the furan nucleus conferred marked antimicrobial activity and that substitution of various radicals on the carbon atom in the number 2 position produced compounds varying in ability to affect various microorganisms. Several nitrofurans are well known to the medical and veterinary professions today; two find practical use in the poultry field: nitrofurazone [(5-nitro-2-furaldehyde semicarbazone)] and furazolidone [N(5-nitro-2 furfurylidene)-1-amino-oxazolidone]. They are effective against various pathogenic protozoa and salmonellae (Grumbles et al., 1954; Roberts, 1954; Lucas, 1955; and Smith, 1955). This paper deals primarily with the effect of another nitrofuran, Furadroxyl [5-nitro-2-furaldehyde-2-(2-hydroxyethyl) semicarbazone], on the growth rate of broiler chicks. This drug is still restricted to experimental use and to our knowledge there is no literature dealing with its effect on growth …
Indirect evidence for the presence and physiological role of endogenous extracellular ATP in the semicircular canal.

Abstract Previous studies have shown that low concentrations of exogenous ATP, added to the perilymphatic fluid, could modify the bioelectrical activity of the isolated semicircular canal of the frog (Rana pipiens). To test the hypothesis that ATP is endogenously present and active in the perilymphatic fluid, the influence of two ATP-purinoceptor antagonists, Reactive Blue 2 and suramin, and of the enzyme, nucleotide pyrophosphatase, were examined. When applied by perilymphatic bath substitution, the three compounds reduced, in a dose-dependent manner, the firing of the afferent fibers monitored in the absence of mechanically-applied stimulation. The response of the afferent fibers, recorded when the sensory cells were mechanically inhibited, was also reduced. No modification of the response to the excitatory phase of the mechanical stimulus was observed in the presence of the two antagonists. In contrast, the signal was significantly reduced by the enzyme. None of the three compounds exhibited an influence on the transepithelial potential, or its variation in response to mechanical stimulation. The ATP-induced modification of the firing rate of the afferent fibers, monitored in the absence of mechanical stimulation, was reduced in the presence of the three drugs. No influence of Reactive Blue 2 and suramin was observed on the increase of the spontaneous firing induced by carbachol. In contrast, the effect of carbachol was decreased by nucleotide pyrophosphatase. The excitatory influence of glutamate on the spontaneous firing was not modified by Reactive Blue 2, while it was slightly increased by suramin and nucleotide pyrophosphatase. The observation that the three compounds, by themselves, exhibit opposite effects to those induced by ATP, together with the antagonistic effects of Reactive Blue 2, suramin and nucleotide pyrophosphatase on the ATP-induced responses, support the hypothesis that endogenous extracellular ATP is present in the perilymphatic compartment and exerts, through the activation of purinoceptors, a significant modulatory influence on the physiology of the isolated semicircular canal of the frog.
Assessing the accuracy of the maximum likelihood estimator: Observed versus expected Fisher information

SUMMARY This paper concerns normal approximations to the distribution of the maximum likelihood estimator in one-parameter families. The traditional variance approximation is 1/1.I, where 0 is the maximum likelihood estimator and fo is the expected total Fisher information. Many writers, including R. A. Fisher, have argued in favour of the variance estimate I/I(x), where I(x) is the observed information, i.e. minus the second derivative of the log likelihood function at # given data x. We give a frequentist justification for preferring I/I(x) to 1/.Io. The former is shown to approximate the conditional variance of # given an appropriate ancillary statistic which to a first approximation is I(x). The theory may be seen to flow naturally from Fisher's pioneering papers on likelihood estimation. A large number of examples are used to supplement a small amount of theory. Our evidence indicates preference for the likelihood ratio method of obtaining confidence limits.
Traffic flow on directed square lattice

Abstract The generic phase transition from a phase of freely flowing traffic of electronic data packets to a congested phase is studied in a very simple model. Here the network is an oriented square lattice. Packets are randomly introduced at the nodes located at one boundary with a certain posting rate, they execute a directed diffusive motion transverse to the boundary and are delivered at nodes positioned at the opposite boundary. There exists the possibility of accumulation of packets forming queues at all nodes and at every time-step data packets up to a maximum number m are allowed to move out of every queue on a first-in–first-out (FIFO) basis. A phase transition between a free-flow to a congested phase is observed at a critical value of the posting rate of packets where the mean load of the system diverges. The characteristic time or latency distribution shows log-normal behavior.
The Macroconidium Appendage in Microsporum Gypseum

The macroconidial appendages in Microsporum gypseum are borne by a group of macroconidia whose frequency in one strain varies with age and growth conditions of the culture. Most frequently the appendages are borne singly on the apical cell; infrequently they are borne singly on the basal cell, in pairs on the apical cell, or one at each end of the macroconidium. Regardless of number and position, the appendages are slender, filamentous, aseptate, typically simple but rarely branched, containing 1-5 nuclei. They are formed after the macroconidia have separated from the conidiophores. In contrast to the germ tubes which are proluced by each macroconidial cell, the appendages are of finer width and determinate growth, and their formation is confined to one or both of the terminal cells of the macroconidium. The dermatophytes, as classified by Emmons (1934), are divided into three imperfect genera, Microsporum, Trichophyton, and Epidermophyton, which are primarily differentiated by morphology of the macroconidia. This classification system has remained unchallenged, and its emphasis on characteristics of the macroconidia has proved valuable in recent discoveries and taxonomy of the new perfect species. It is surprising, therefore, that the macroconidium appendage that is so frequently encountered in Microsporum gypseum (Bodin) Guiart & Grigorakis, had passed unnoticed until Stockdale (1963) revised the taxonomy of this complex species and its perfect states. She observed that the "slender, whip-like" appendage, borne on the apical cell of the macroconidium, is formed frequently in certain strains of M. gypseum but rarely in M. fulvum. Little has been known about the development, cytology, and function of the appendages, the aspects that constitute the subject of this
Novel delivery of image processing functions to PACS diagnostic viewing stations

We have developed a new mechanism for the delivery of image processing functions to multi-modality PACS diagnostic viewing stations. The tools use the Java programming language. The core visible element of this system is a graphical user interface component that moves around the image(s) like a magnifying glass. Included with the component are controls that are capable of manipulating the image seen within it. The client-server architecture allows for dynamically adding and removing image processing functions as they are developed. In addition to several standard image-processing functions, the component has several novel functions.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Regularized Product Integration for Hadamard Finite Part Integrals

The computation of the Hadamard finite-part integral is considered as an ill-posed problem and treated by a product integration technique. It is shown that, with an appropriate choice of the mesh width, the method is a regularizing algorithm in the sense of Tikhonov, and an order of convergence is derived.
Advocacy for Emergency Medical Services for Children: Education, Practice, and Policy Implications

Advocacy for maintaining and expanding Emergency Medical Services for Children is needed on many fronts. Pediatric emergency medicine (PEM) physicians are uniquely qualified to serve this role due to their expertise in the acute care of sick or injured pediatric patients. Given this, in addition to maintaining the highest standards in the emergency departments in which they work, PEM physicians also have responsibilities in the education, training, and practice of emergency medical services providers in their region. These providers are also well positioned to advocate for Emergency Medical Services for Children on a policy level at local, regional, and state governments and in organizations that deal with the care of children in both the prehospital and hospital arenas. Greater engagement by PEM physicians in such activities is required to optimize pediatric care across the spectrum of emergency services.
Analyzing survey experiments having spatial variability with an application to a sea scallop fishing experiment

Abstract This paper considers discrete survey sampling in an area, when it can be assumed that observations near each other will be positively correlated. We consider two methods of analyzing such data: classic randomized complete block design (RCBD), and random field linear models (RFLMs) where the spatial covariance function is estimated directly from the data. When normality can be assumed, RFLM reduces to the likelihood analysis for the model Y∼N[Xβ,Σ(θ)]. The mean E(Y)=Xβ is the standard linear model formulation, and the covariance function Σ(θ) is modeled using the exponential, Gaussian, or spherical formulation from geostatistics. Hypothesis tests for β were formulated using standard RCBD-ANOVA; and likelihood ratio and Wald statistics were used for the RFLM model. Simulations indicate that for blocked experimental designs both RCBD-ANOVA and RFLM perform well. For experimental designs in which adequate blocking is unavailable, simulations indicate standard ANOVA can perform poorly, but RFLM may be a useful tool to improve the quality of inference that can be derived. The RCBD-ANOVA and RFLM were applied to catch data from a sea scallop survey experiment in the New York Bight conducted by the Northeast Fisheries Science Center using three research vessels. Both RCBD-ANOVA and RFLM analysis showed there was no significant difference in the fishing power of these vessels.
Ionospheric Virtual Height Measurements at 100 Kilocycles

A simple high-power ionosphere sounding equipment for use at low frequencies is described. Its application to the measurement of virtual height at vertical incidence at a carrier frequency of 100 kc is reported. Results of nearly a year of intermittent night-time measurements showed a remarkably large variation in virtual height which ranged from about 84 km to as high as 106 km. Some evidence was found to indicate that frequently at night the reflecting region consists of clouds or patches of ionization, rather than the more nearly uniform ionization characteristic of the regular layers at high frequencies. A rotation of the polarization of the reflected signal with respect to that of the transmitted signal was observed.
Using Competitive Advantage Theory to Analyze IT Sectors in Developing Countries: A Software Industry Case Analysis

The purpose of this paper is to provide guidance for researchers and analysts on when, why, and how to apply Porter's competitive advantage theory to analysis of IT sectors in developing countries. To date, this theory has been rather poorly applied in such analysis, yet the question of how developing countries—as latecomers—can create competitive advantage in IT industries remains one of critical interest to policy makers, entrepreneurs, and international agencies. Understanding of IT sector growth is particularly important, in light of its significant potential contribution to economic development. From the five IT sectors—goods, software, infrastructure, services, and content— this paper focuses on software. Having provided a thorough explanation of competitive advantage theory, it applies this theory to the case of India's software industry, which it finds does have a competitive advantage, based on variables such as ever-increasing advanced skills, domestic rivalry, clustering, and government policy/vision. To assist researchers, the paper identifies emergent challenges to Porter's theory that can be resolved relatively easily but also some less tractable problems around the issues of government policy, processes of upgrading/innovation, and local/global linkages. All these require some identified amendments to Porter's original ideas. Nonetheless, Porter's theory is seen to be a valuable tool for development informatics/ICT4D research, applicable to a variety of IT sectors—not just software—and offering answers to questions about whether sectors are competitive, why they are or are not competitive, and what should be done to improve or sustain competitive advantage.
In-flight calibration of shortwave active cavity radiometers: approach and results

Beginning in 1984, three Earth Radiation Budget Experiment (ERBE) spacecraft were launched to measure the Earth's radiation budget components: Solar-incident, Earth-emitted, and Earth-reflected radiation. The National Aeronautics and Space Administration's Earth Radiation Budget Satellite was launched in 1984 in a low-inclination orbit, and the National Oceanic and Atmospheric Administration's NOAA-9 and NOAA-10 satellites were launched in Sun-synchronous polar orbits in 1984 and 1986, respectively. This paper describes the method used for correcting for changes in the gains and offsets used for determining the final count conversion coefficients used in processing the in-flight calibration data. We also describe a technique for the determination of WFOV shortwave offsets which proxies for nighttime offsets during months of continuous daytime only orbits near sunrise and sunset when no nighttime measurements are available. The final result covering the period of 1984 through 1991 are discussed in this paper.
Second Generation Gravitational Wave Detectors

Second generation gravitational wave detectors are in the process of being researched, designed, and constructed. They include Advanced LIGO in the United States, Advanced Virgo in Italy, the Large Cryogenic Gravitational-wave Telescope in Japan, GEO High Frequency in Germany, and the Australian International Gravitational Observatory in Australia. It is expected that these second generation detectors will have the sensitivity needed to regularly detect gravitational waves and usher in the era of gravitational astronomy. To achieve this sensitivity, new technology to reduce seismic, thermal, quantum and other noise sources is being developed and implemented. Advanced LIGO, Advanced Virgo, and GEO HF have already been funded and are building and buying new hardware, while LCGT is awaiting a funding decision, and AIGO is preparing to submit a funding proposal.
Growth and development of folk botanical life forms in the Mayan language family

This paper examines the growth of folk botanical life-form categories I for example, “tree,” “vine”) in the Mayan language family of Mesoamerica. Reconstruction of life-form systems for protostages in Mayan language history indicates that the addition of life-form terms to Mayan vocabularies has conformed to an earlier proposal of a botanical life-form encoding sequence (Brown 1977a). In addition, the vast majority of Mayan botanical life forms have been added in very recent times. Apparently, global life-form growth has taken place primarily during the last few thousand years of human history. An explanation of this phenomenon is proposed. Principles underlying botanical nomenclatural development are also formulated and discussed.
Building large-scale digital libraries

In this era of the Internet and the World Wide Web, the long-time topic of digital libraries has suddenly become white hot. As the Internet expands, particularly the WWW, more people are recognizing the need to search indexed collections. The paper discusses some of the Digital Library Initiative (DLI) projects which are a good measure of the research into large scale digital libraries. They span a wide range of the major topics necessary to develop the National Information Infrastructure.
Socialization tactics in wikipedia and their effects

Socialization of newcomers is critical both for conventional groups. It helps groups perform effectively and the newcomers develop commitment. However, little empirical research has investigated the impact of specific socialization tactics on newcomers' commitment to online groups. We examined WikiProjects, subgroups in Wikipedia organized around working on common topics or tasks. In study 1, we identified the seven socialization tactics used most frequently: invitations to join, welcome messages, requests to work on project-related tasks, offers of assistance, positive feedback on a new member's work, constructive criticism, and personal-related comments. In study 2, we examined their impact on newcomers' commitment to the project. Whereas most newcomers contributed fewer edits over time, the declines were slowed or reversed for those socialized with welcome messages, assistance, and constructive criticism. In contrast, invitations led to steeper declines in edits. These results suggest that different socialization tactics play different roles in socializing new members in online groups compared to offline ones.