cssi/SciSciGPT-SciSciNet huggingface dataset:
Potential for augmentative biological control of black bean aphid in California sugarbeet

In northern California, black bean aphid (Aphis fabae Scopoli complex) can be a major pest of sugarbeet, particularly in spring-planted fields. The major natural enemies of the aphid are predators, including the coccinellidsHippodamia convergens Guerin,Coccinella novemnotata Herbst &C. septempunctata L., and the chrysopidsChrysopa oculata Say &C. nigricornis Burmeister. Augmentative releases of eggs of eitherChrysoperla carnea (Stephens) orC. rufilabris (Burmeister) failed to significantly reduce aphid populations under field conditions. This was attributed in part to incompatibility between black bean aphids and lacewing larvae from commercial sources. Application of food sprays containing yeast hydrolysate, sucrose and molasses resulted in increased densities of eggs and adults ofC. carnea in treated plots. These results suggest that the potential for augmentative biological control of black bean aphid through the application of food sprays is greater than that for release of commercially available lacewings. Regardless of method, an holistic approach to augmentation that takes into account the ecological structure of the target agroecosystem will be required. Some aspects of “pre-emptive” biological control are discussed.
Apoptosis and p53 expression in rat adjuvant arthritis.

The kinetics of apoptosis and the apoptosis-regulating gene p53 in adjuvant arthritis (AA) were investigated to assess the value of the AA rat model for testing apoptosis-inducing therapies. Very few terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) nick end-labeling (TUNEL)-positive cells were detected during the early phases of AA, but on day 23 (chronic arthritis) the percentage of TUNEL-positive cells was significantly increased. Expression of p53 in synovial tissue gradually increased from days 5-23, which was markedly higher than p53 levels in rheumatoid arthritis (RA) synovium. Significant apoptosis only occurs late in rat AA and is concordant with marked p53 overexpression, making it useful model for testing proapoptotic therapies, but rat AA is not the best model for p53 gene therapy because dramatic p53 overexpression occurs in the latter stages of the disease.
Detection of Aliasing in Persistent Signals

We explain why aliasing can be detected in a generic temporallysampled stationary signal process. We then define a concept of stationarity that makes sense for single waveforms. (This is done without assuming that the waveform is a sample path of some underlying stochastic process.) We show how to use this concept to detect aliasing in sampled waveforms. The constraint that must be satisfied to make detection of aliasing possible is shown to be fairly unrestrictive. We use simple harmonic signals to elucidate the method. We then demonstrate that the method works for continuous-spectrum �.
Occupation of topological Floquet bands in open systems

Floquet topological insulators are noninteracting quantum systems that, when driven by a time-periodic field, are described by effective Hamiltonians whose bands carry nontrivial topological invariants. A longstanding question concerns the possibility of selectively populating one of these effective bands, thereby maximizing the system's resemblance to a static topological insulator. We study such Floquet systems coupled to a zero-temperature thermal reservoir that provides dissipation. We find that the resulting electronic steady states are generically characterized by a finite density of excitations above the effective ground state, even when the driving has a small amplitude and/or large frequency. We discuss the role of reservoir engineering in mitigating this problem.
Persistence of the viral genome in adenovirus type 12-infected hamster cells.

Abstract Induction of T antigen by adenovirus type 12 was studied in growing and growth-inhibited cultures of the Nil-2 line of Syrian hamster cells. At a viral input multiplicity of 10, neoantigen was present in 100% of the cells by 24 hr. T antigen gradually disappeared in descendants of these cells so that 2 weeks after infection only 1% gave specific immunofluorescence. When cellular replication was prevented by addition of fluorodeoxyuridine, T antigen persisted in all cells for the 2-week period. Upon infection of growing cultures with purified 3H-labeled adenovirus type 12 and autoradiographic analysis of the cells at various times thereafter, a gradual reduction in labeled nuclear loci was noted which paralleled the decrease in T antigen-containing cells. In nongrowing cultures, no change in labeled loci was noted. Correlation of T antigen and labeled loci revealed that fluorescent cells contained, on the average, about 10 times more silver grains than nonfluorescent cells. All of 92 preselected fluorescent cells showed labeled loci, whereas, of 100 nonfluorescent cells, 18 were free of silver grains. The implications of these findings are discussed.
Viscoplastic models for high temperature applications

Abstract The information specific to the material deformation behavior in stress analyses of structures and manufacturing processes is contained in the material model or the constitutive equation. In the past these models had to be linear and simple to perform the stress analyses economically. Large safety (ignorance) factors made up for the simplicity. The availability of inexpensive computing power and the demands of society for reliability and safety require an improvement of stress analyses by using new and realistic constitutive equations of nonlinear, inelastic behavior of metals and their alloys. Presently used nonlinear models such as plasticity and creep theory are by far the oldest link in the stress analysis package. Test results obtained with modern mechanical testing machines and theoretical developments during the past several decades suggest that viscoplastic models using state variables are much-improved models. It is recommended that these models be carefully reviewed, further developed when needed and recommended by interdisciplinary, technology specific committees of materials, mechanics, testing and computing experts. Rather than having databases with material constants, databases containing `the constitutive model' for different alloys and associated constants should be established. The analyst would call up `the model', say, for annealed stainless steel and load it into the stress analysis program.
Molecular mechanisms in hepatocellular carcinoma development

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. It usually develops in patients with chronic viral hepatitis, aflatoxin exposure, or excessive alcohol use. Most patients with HCC present with advanced disease and have a poor prognosis. The implementation of antiviral drugs and the availability of a vaccine for hepatitis B should help reduce the incidence of HCC. Considerable effort has now focused on unraveling the molecular pathogenesis of HCC in order to design better treatments, or to prevent the disease altogether. However, so far, the pathogenesis of HCC appears to be quite heterogenous among patients. In particular, several mechanisms of tumorigenesis seem to be involved, including loss of tumor suppressor gene function, oncogene activation, direct viral effects, DNA methylation, and angiogenesis. It is not clear which events are critical in tumor initiation versus tumor progression. RNA expression arrays and proteomics hold promise to provide further clues about this common and complex cancer.
Estimation of failure probability based on significant damages

Abstract This article presents a technique for estimating the failure probability based on damages that exceed a threshold value. It assumes that the number of earthquakes over a given interval follows a non-homogeneous Poisson process and that repairs are applied in proportion to the intensity of this process. It uses simulated data for demonstration.
Pyrophosphate-dependent sucrose metabolism and its activation by fructose 2, 6-bisphosphate in sucrose importing plant tissues

In the presence of pyrophosphate and uridine diphosphate, sucrose was cleaved to form glucose 1-phosphate and fructose with soluble extracts from sucrose importing plant tissues. The glucose 1-phosphate then was converted through glycolysis to triose phosphates in a pyrophosphate-dependent pathway which was activated by fructose 2, 6-bisphosphate. Much less activity,
Preventing estrogen receptor action with dimer-interface peptides.

Abstract The human estrogen receptor-α (hER) is a ligand-activated transcription factor that functions as a homodimer. We sought to further understand the molecular processes involved in dimerization, and to develop a reagent that may function as an antiestrogen independent of the ligand binding site. To this end, we designed a 16-residue ‘dimer-interface’ oligopeptide derived from the helical region of the hER which is directly involved in dimerization. This peptide, termed the I-box peptide, has a high helical propensity in aqueous solution. The I-box peptide blocks hER action by causing aggregation and precipitation of both the ligand-bound and apo-hER. This effect is dependent on the helical nature of the peptide. A single Ile to Pro mutation in the helical region of the I-box peptide significantly reduces the helical content and abolishes the precipitation activity. Furthermore, the peptide activity appears to be specific for the hER. The I-box peptide does not significantly affect other proteins or steroid receptors tested. A homologous peptide derived from the nuclear receptor RXRα dimer interface, and a LXXLL-containing peptide from the coactivator TIF2 have no detectable in vitro effect on hER function or solubility. Our data suggest that rationally designed molecules capable of affecting steroid receptor quaternary structures may be potential avenues for the development of specific inhibitors of this class of proteins.
A Lumped Parameter Mathematical Model of the Splanchnic Circulation

A lumped parameter mathematical model to describe the propulsion of blood in the splanchnic circulation was developed by integrating the principles of mechanics and physiology. A set of governing equations by derived by specifically considering the contractility of the portal vein, hepatic vein, liver sinusoids, and of the draining lymphatics. These equations were then simulated on a computer. The present simulation results substantiate previous experimental observations that hepatic venous pressure leads to portal hypertension and increased liver interstitial fluid volume.
Effect of chromium on room temperature ductility and fracture mode in Fe3Al

The unique electrical, magnetic, and corrosion resistance properties of iron-aluminides with compositions near that of Fe/sub 3/Al have long stimulated the interest of material scientists. Combined with low cost of iron and aluminum, lower density compared with steels, and adequate strength at temperatures below 600/sup 0/C, iron aluminides are attractive candidates for structural applications in many industries. However, the lack of ductility at ambient temperatures and a sharp drop in strength above 600/sup 0/C have been major obstacles to their development as structural materials. The authors studies, conducted using a base alloy of Fe-28 at.% Al, have indicated that the room temperature ductility can be improved by a factor of at least two by additions of chromium of up to 6 at.%. It has been found that, although the room temperature strengths are decreased slightly, the elongation to fracture is increased from below 4% with no chromium to 8-10% for additions of 2-6 at.% chromium. Elongations of up to 13% were produced by varying the rolling schedule and/or a post-rolling heat treatment.
SU-E-T-324: Multi-Institution Comparison for TrueBeam Commissioning Data and Beam Modeling Verification Using An Anisotropic Analytical Algorithm

Purpose: To perform a dosimetric comparison of TrueBeam(TB) commissioning data between UAMS and other institutions; verify the beam modeling accuracy. Methods: Dosimetric data including percentage depth dose (PDD), penumbra, mlc transmission leakage(TL) and dosimetric leaf gap(DLG) for 6MV, 6MV FFF, 10MV and 10MV FFF X‐ray beams were compared with two published papers (Chang et.al (Publication #1) and Jan et.al (Publication #2)). The beam modeling accuracy was evaluated by comparing the PDD, absolute point dose and patient dose from Eclipse TPS calculation using AAA algorithm and from measurements. Point dose was measured using calibrated ion chambers of different sizes at different depths, different field sizes for all four energies. Patient IMRT and VMAT doses were verified using PTW Octavius ion chamber and SunNuclear ArcCheck diode array. Results: The comparison of UAMS TB commissioning data with published data shows that the differences for PDDs are within 1% except for 10MV FFF beam, where the maximum difference is within 3% as compared with Publication #2. The differences for penumbra are within 1mm for all four energies. At UAMS, the mlc TL and DLG are 1.21% and 0.45mm for 6MV; 1.02% and 0.348mm for 6MV FFF; 1.39% and 0.545mm for 10MV; and 1.2% and 0.484mm for 10MV FFF beams respectively. These results are in good agreement with those from the other two institutions. For Eclipse beam modeling evaluation, all point dose measurements are within 3% compared with the Eclipse TPS calculation except for the 1.0 cm2 field size, where the maximum difference is 5%. All patient QAs were acceptable with a gamma agreement index score of 95% or higher based on the 3%, 3mm criteria. Conclusion: Commissioning data for the UAMS TB was clinically identical with the published data from two other institutions. The beam modeling verification shows that Eclipse modeling of these four beams is accurate.
Biologics in Foot and Ankle Surgery

This article is another review of clinical application of the use of bone morphogenetic proteins, specifically rhBMP2 Infuse Bonegraft, in the treatment of both acute and chronic fracture and fusion situations. Overall experience is reported with particular detail to the use of biologics in the treatment of problems involving the tibia, foot, and ankle.
Effects of SAG12-ipt expression on cytokinin production, growth and senescence of creeping bentgrass (Agrostis stolonifera L.) under heat stress

The study was conducted to determine the effects of expression of a transgene encoding adenine isopentenyl transferase (ipt), which controls cytokinin synthesis, on growth and leaf senescence of creeping bentgrass (Agrostis stolonifera L.), subjected to heat stress. Creeping bentgrass (cv. Penncross) was transformed with ipt ligated to a senescence-activated promoter (SAG12). Eight SAG12-ipt transgenic lines exhibiting desirable turf quality and a transgenic control line (transformed with the empty vector) were evaluated for morphological and physiological changes under normal growth temperature (20°C) and after 14 days of heat stress (35°C) in growth chambers. Six of the SAG12-ipt lines developed more tillers than the control line during establishment under normal growth temperature of 20°C. Following 14 days of heat stress, four of the SAG12-ipt lines had increased 65–83% of roots and for all six SAG12-ipt lines root elongation continued, whereas root production ceased and total root length decreased for the control line. Root isopentenyl adenine (iPA) content increased 2.5–3.5 times in five of the SAG12-ipt lines, whereas in the control line iPA decreased 20% after 14 days at 35°C. Total zeatin riboside (ZR) content was maintained at the original level or increased in five of the SAG12-ipt lines, whereas in the control line ZR decreased under heat stress. Our results suggest expression of SAG12-ipt in creeping bentgrass stimulated tiller formation and root production, and delayed leaf senescence under heat stress, suggesting a role for cytokinins in regulating cool-season grass tolerance to heat stress.
The emergence of social play in infancy: A proposed developmental sequence of infant-adult social play

Adults engage in social interactions with infants from the moment of birth. Many of these interactions take the form of early social play, often thought to begin when peer interaction begins. This article proposes a developmental sequence of adult-infant social play. The proposed sequence is based on, and approximately reverses, the Howes (1980) peer play scale. Support for the developmental sequence is culled from pertinent literature. The sequence is proposed as a starting point for further discussion and research.
K+p interactions near 3 GeV/c (II): Baryon resonance production

Abstract Baryon resonance production in quasi-two-body reactions has been studied for the channels K+p→K°pπ+, K+nπ+ and K+pπ° at beam momenta of 2.53, 2.76 and 3.20 GeV/c. The production cross sections, four-momentum transfer distributions and density matrix elements are given for the Δ(1236), N∗(1400), N∗(1500) and N∗(1680) states. The reaction K+p→K°Δ++(1236) is compared to the line reversed reaction K − n → K °Δ − and the charge-exchange SU(3) sum rule for pseudo-scalar meson plus Δ(1236) is tested.
Mutagenesis of human fibrinogen γ chain 259-411 synthesized in E. coli. Further characterization of the role of the disulfide bond CYS326-CYS339 in calcium binding

We have produced human fibrinogen γ259–411 in Escherichia coli in order to study the relationship between the calcium binding activity of the polypeptide and the integrity of the disulfide bond cysteine326-cysteine339. The polypeptide was produced from a plasmid expression vector at approximately 5 micrograms per milliliter of bacterial culture. The identity of the polypeptide was confirmed by N-terminal amino acid sequence analysis. The expression vector was modified by oligonucleotide directed mutagenesis to remove the nucleotides encoding cysteines γ326 and γ339. The calcium binding activity of wild-type and altered polypeptides were compared using a solid phase assay. Our results indicate that removal of the two cysteine residues had no appreciable effect on calcium binding activity. We conclude that the integrity of the disulfide bond cysteine326-cysteine339 is not critical for calcium binding to γ259–411.
Shared Decision Making in Mental Health Treatment: Qualitative Findings from Stakeholder Focus Groups

Purpose This article reports on findings from seven stakeholder focus groups conducted in exploring shared decision making (SDM) between provider and consumer in mental health (MH) treatment in public MH. Basic Procedures Seven focus groups were conducted with stakeholders—consumers, family members, prescribers, MH clinicians, and rural providers. Each of the focus groups was recorded digitally, transcribed into text, and analyzed qualitatively for recurring themes. Main findings Provider barriers to SDM include history of the medical model, MH crises, lack of system support, and time. Consumer-related barriers included consumer competency, fears, insight, literacy, and trauma from past experiences. Information-exchange issues include consumer passivity, whether consumers could be viewed as experts, and importance of adequate history information. New skills needed to practice SDM included provider's knowledge about alternative treatments, mastery of person-first language, and listening skills; consumer's ability to articulate their expert information; and computer skills for both providers and consumers. Outcomes expected from practice of SDM include greater sharing of power between provider and consumer, greater follow-through with treatment plans, greater self-management on the part of consumers, and improved therapeutic alliances. Principal conclusions Implementing SDM in public MH will impact consumers and their families, providers, prescribers, and administrators. More SDM trials in public MH are needed to answer some of the many questions that remain.
Comparative Growth Rates of Selected Anaerobic Species in Four Commonly Used Broth Media

Generations times (g(t)) of selected anaerobic species were compared in four culture media commonly used for anaerobic bacteria to evaluate these media for growing inocula for anaerobic antibiotic susceptibility determinations. Twenty-two clinical isolates of Bacteroides fragilis, Fusobacterium spp., Clostridium perfringens, and Clostridium spp. were tested in Schaedler broth, supplemented Lombard-Dowell broth, supplemented thioglycolate broth, and supplemented peptone-yeast extract-glucose broth. Growth curves were performed in an anaerobic chamber; changes in cell density were followed by viable count procedures and, in some cases, turbidometric procedures. The clostridia did not appear to have significantly different g(t) values in different media. The g(t) values for the five clostridial species tested ranged from 18 to 45 min. The fusobacteria also showed no apparent differences in g(t) values in the four media; values ranged from 51 to 60 min. The two subspecies of B. fragilis tested showed no significant differences in g(t) values when compared with each other in the same media. The combined data, however, indicated that the growth rate in Schaedler broth was faster than in the other media (average g(t), 45.1 min), whereas the growth rate in peptone-yeast extract-glucose was slower (average g(t), 58.2 min). The growth rates in supplemented thioglycolate and supplemented Lombard-Dowell broth (average g(t), 53.6 min and average g(t), 51.0 min, respectively) were not significantly different.
Stimulus size affects rod influence on tritan chromatic discrimination

A signal-detection procedure was used to measure the influence of rods on S-cone-mediated ("tritan") chro- matic discrimination in normal trichromatic human observ- ers. Rod influence on discriminability of both increments and decrements in S-cone excitation was assessed by com- paring cone-plateau (minimizes rod influence) and dark adapted (maximizes rod influence) conditions. For 1° stim- uli, rods impaired tritan discrimination, especially for S- cone decrements. For 8° stimuli, rods had no systematic effects. This confirms that rods have the same direction of effect (impairment) on tritan discrimination as has been shown for Rayleigh (L-M) discrimination. However, the size dependence of the rod effect on tritan discrimination is opposite to that previously shown for either Rayleigh dis- crimination or hue appearance. This provides further evi- dence for separable rod influences on S-cone and L-M cone pathways. © 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S65-S68,
On simplicial commutative algebras with vanishing André-Quillen homology

In this paper, we study the Andre-Quillen homology of simplicial commutative l-algebras, l a field, having certain vanishing properties. When l has non-zero characteristic, we obtain an algebraic version of a theorem of J.-P. Serre and Y. Umeda that characterizes such simplicial algebras having bounded homotopy groups. We further discuss how this theorem fails in the rational case and, as an application, indicate how the algebraic Serre theorem can be used to resolve a conjecture of D. Quillen for algebras of finite type over Noetherian rings, having non-zero characteristic.
A Role for 12-lipoxygenase in Nerve Cell Death Caused by Glutathione Depletion

An early and highly specific decrease in glutathione (GSH) in the substantia nigra is associated with Parkinson's disease, and low levels of GSH lead to the degeneration of cultured dopaminergic neurons. Using immature cortical neurons and a clonal nerve cell line, it is shown that a decrease in GSH triggers the activation of neuronal 12-lipoxygenase (12-LOX), which leads to the production of peroxides, the influx of Ca2+, and ultimately to cell death. The supporting evidence includes: 1) inhibitors of arachidonate metabolism and 12-LOX block cell death induced by GSH depletion; 2) there is an increase in 12-LOX activity and a membrane translocation in HT22 cells, and an induction of the enzyme in primary cortical neurons following the reduction of GSH; 3) 12-LOX is directly inhibited by GSH; and 4) exogenous arachidonic acid potentiates cell death. These data show that the LOX pathway is a critical intermediate in at least some forms of neuronal degeneration.
Infiltrated lanthanum strontium chromite anodes for solid oxide fuel cells: Structural and catalytic aspects

Abstract Infiltration is a widely used fabrication method for solid oxide fuel cell (SOFC) composite electrodes. Here we report a study of the structure and electrocatalytic properties of SOFC anodes composed of a layer of lanthanum, strontium chromite (La0.8Sr0.2CrO3, LSCr), both with and without added transition metal dopants, infiltrated into a porous yttria-stabilized zirconia (YSZ) matrix. The structural evolution of the electrode upon reduction and under typical SOFC operating conditions is compared to that reported previously for La0.8Sr0.2Cr0.5Mn0.5O3–YSZ composite anodes. For the transition metal doped materials, a portion of the metal dopants were found to be exsolved from the LSCr lattice upon reduction and to be effective in promoting electro-oxidation of hydrogen. Exsolved cobalt particles were also found to be relatively stable when exposed to hydrocarbon fuels with low activity for the formation of carbon deposits.
Rigorous thermodynamic treatment of gas adsorption

Multicomponent adsorption equilibria are predicted from theories based on experimental data for single-gas adsorption isotherms. Theories of multicomponent adsorption differ in the details of their results but should agree in special cases such as low surface coverage and ideal solution behavior. This paper is a summary of rules, limits, and consistency requirements that apply to adsorption of single gases and their mixtures. These rules and limits provide a basis for comparing theories with each other and with experimental data.
Enzymatic and nonenzymatic mechanisms for ferric leghemoglobin reduction in legume root nodules

Abstract Evidence is presented for the operation in nodules of at least four systems for restoring functional ferrous leghemoglobin (LB2+) from its inactive, ferric form. (i) Reduction of ferric leghemoglobin (LB3+) by a reductase. The enzyme is a flavoprotein of 100 kDa with two equally sized subunits andexhibits a Km of 9 microM for soybean LB3+ component a and a Km of 51 microM for NADH. NADPH is only 30% (initial velocities) as effective as NADH. LB3+ reductase converts 215 nmol of LB3+ to LB2+.CO (or Lb2+.O2) per mg of protein per min and does not require an exogenous electron carrier. The enzyme shows similar affinity for soybean, bean, and cowpea LB3+, but different Vmax values. The reductase is inactive with LB3+ is bound to nicotinate or NO2-. (ii) Direct reduction of LB3+ by NAD(P)H, ascorbate, and cysteine. Reduction by NAD(P)H is greatly stimulated by trace amounts of metals such as Mn2+. (iii) Reduction of Lb3+ by the flow of electrons from NAD(P)H to free flavins to LB3+. The reaction does not occur via O2.- or H2O2, and thus NAD(P)H-reduced flavins can directly reduce LB3+. The efficiency of the reaction follows the order riboflavin > FMN > FAD. (iv) Reduction of LB3+ by an unknown compound, B, of nodules. B has a molecular mass < 1 kDa and is heat-stable. The reaction mediated by B differs from those mediated by flavins and metals in several ways, requires NAD(P)H, and generates O2.-.
How does dementia affect driving in older patients

Driving is a complex activity that always becomes impaired at some point in older adults with degenerative dementia. Over time, disruption of the visual processing circuits of the brain that link the occipital and prefrontal regions, particularly in the right hemisphere, leads to increasing degrees of driving impairment that ultimately preclude safe driving. Neuropsychological tests of visuospatial ability, executive function and attention that tap into the integrity of these brain regions provide the clinician with important information regarding the need for a formal determination of driving competence. Enhancement of cognitive function in these domains through anti-dementia therapy and exercise may partially mitigate risk; however, all drivers with dementia must ultimately retire from driving when dementia becomes moderately severe, and often in earlier stages of the illness. Future efforts to improve screening tests for hazardous driving and to develop interventions to help prolong the time that drivers with mild dementia can continue to drive safely are needed for our increasingly aged and mobile population.
Variable rules and literary style

Since the time when Labov1 introduced the notion of the variable linguistic rule, several researchers into linguistic variability have suggested that the idea may be of use in the study of style. Cedergren and D. Sankoff claim that the idea of the variable rule "has wide ramifications for stylistics,"2 echoing a sentiment expressed by G. Sankoff.3 And Enkvist states that "Labov's method is of potential interest.. . to students of style precisely because it shows us an example of how probabilistic quantification can be built into a generative grammar."4 But as yet no effort has been made to determine whether stylistic variation can in fact be described in the framework of variable rules. This paper reports on a preliminary attempt to describe some aspects of the metrical styles of Robert Herrick and Ben Jonson according to the model of variable rules presented in Cedergren and D. Sankoff.s Metrical style was chosen as the area of investigation for two reasons. Cedergren points out that "Phonology has provided the first testing ground for theories of linguistic variability partly due to the possibility of constructing data sets large enough for simultaneous analysis along many dimensions of variation. With massive data, we are more likely to be bound by the patterning existing in the data, and less likely to resort to generating biased artificial data in order to. fill vacant 'cells' in tables, to be tempted into lengthy a posteriori speculations to explain away each piece of data which does not fit our models, or to dismiss systematically patterned exceptions as 'performance error.' "6 A phonological aspect of stylistic variability-specifically, the presence or absence of the phonological feature of stress-is desirable as a "first testing ground" for the theory of stylistic variability precisely because it enables us to generate massive data sets. A 1136 line sample of iambic pentameter verse from Herrick and Jonson provided an opportunity to measure the variable of stress 4544 times, a number sufficient for a consideration of many relevant dimensions of variation. A syntactic or lexical variable would not readily supply us with a large enough data set. A second reason for choosing metrical style is that there exists already a generative grammar of iambic pentameter which provides a ready-made framework for the investigation of metrical variation according to a variable rule. The Halle-Keyser theory7 regards the underlying structure of the iambic pentameter line as a series of positions:
Adaptations in AMPA receptor transmission in the nucleus accumbens contributing to incubation of cocaine craving

Cue-induced cocaine craving in rodents intensifies or "incubates" during the first months of withdrawal from long access cocaine self-administration. This incubation phenomenon is relevant to human users who achieve abstinence but exhibit persistent vulnerability to cue-induced relapse. It is well established that incubation of cocaine craving involves complex neuronal circuits. Here we will focus on neuroadaptations in the nucleus accumbens (NAc), a region of convergence for pathways that control cocaine seeking. A key adaptation is a delayed (~3-4 weeks) accumulation of Ca(2+)-permeable AMPAR receptors (CP-AMPARs) in synapses on medium spiny neurons (MSN) of the NAc. These CP-AMPARs mediate the expression of incubation after prolonged withdrawal, although different mechanisms must be responsible during the first weeks of withdrawal, prior to CP-AMPAR accumulation. The cascade of events leading to CP-AMPAR accumulation is still unclear. However, several candidate mechanisms have been identified. First, mGluR1 has been shown to negatively regulate CP-AMPAR levels in NAc synapses, and it is possible that a withdrawal-dependent decrease in this effect may help explain CP-AMPAR accumulation during incubation. Second, an increase in phosphorylation of GluA1 subunits (at the protein kinase A site) within extrasynaptic homomeric GluA1 receptors (CP-AMPARs) may promote their synaptic insertion and oppose their removal. Finally, elevation of brain-derived neurotrophic factor (BDNF) levels in the NAc may contribute to maintenance of incubation after months of withdrawal, although incubation-related increases in BDNF accumulation do not account for CP-AMPAR accumulation. Receptors and pathways that negatively regulate incubation, such as mGluR1, are promising targets for the development of therapeutic strategies to help recovering addicts maintain abstinence. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.
Optical tolerances and electric fields in resonant reflectors.

The importance of flatness, parallelism, and equality in thickness of the elements and spacers of a resonant reflector is discussed. Using the matrix method, the reflectivity vs wavelength is computed for several types of resonators, the thicknesses of whose elements were subject to variations. For a two-element device, the exact mechanical thickness of the spacer is not important, but the equality of thickness of the dielectric elements is critical. For a three- or four-element device, the exact thickness of the center element is least important to reflectivity, but the reflectivity decreases if the total error in orders on either side of the center approaches ½. The results indicate that it is extremely difficult to produce a practical device of this complexity. Pressure and temperature scanning is discussed. Experimental results were obtained for two-element devices showing the importance in equality of thickness and the sensitivity to nonparallelism of the spacer. The relative electric field strengths within the reflector were mapped to investigate susceptibility to radiation damage. The amplitude of the field and the position in the resonator where damage would first occur depends upon the reflectivity at the wavelength used.
Delayed matching-to-sample in rats in a Y-maze: Instances of facilitation and immediate cross-modal transfer

Of 6 rats initially trained on matching-to-sample (MTS) with black/white stimuli, 3 learned the problem and, on delayed matching, produced a stable forgetting function. One rat that failed with black/white stimuli learned hardware cloth/smooth floor MTS. Two of the 4 learners showed immediate transfer of matching to an alternate stimulus dimension. All rats that learned were trained with a differential outcome condition that was shifted to equal outcomes after clear preference for superior outcome had developed, that is, after they attended to the appropriate dimension. All rats under this condition learned in fewer than 700 trials.
Changes over time in position and periodontal probing status of retained third molars.

Purpose This study was designed to assess changes over time in third molar position relative to the occlusal plane and in the periodontal probing status of third molars in asymptomatic subjects who had at least 1 third molar below the occlusal plane at baseline and retained all third molars to follow-up. Patients and Methods Between 1998 and 2002, healthy subjects with 4 asymptomatic third molars and adjacent second molars were enrolled in an institutional review board (IRB)-approved longitudinal study. Clinical and radiographic data of 146 subjects who had at least 1 third molar not fully erupted at baseline with at least 2-year follow-up were analyzed. At baseline and longest follow-up, full mouth periodontal probing, 6 sites per tooth, including third molars was conducted. An indicator variable was used to record periodontal status (probed, not probed) for each third molar. A periodontal probing depth (PD) greater than or equal to 4 mm in the third molar region was considered indicative of periodontal pathology. Panoramic radiographs were analyzed to assess whether unerupted third molars erupted to the occlusal plane. To assess descriptively the influence of age and length of follow-up on the change in third molar position and periodontal status, subjects were stratified by age at enrollment as younger ( Results Sixty-six percent of the 146 subjects were less than 25 years old at enrollment. The majority were female and Caucasian. Sixty-eight percent of the 97 younger subjects and 43% of the 49 older subjects presented at baseline with all 4 third molars not fully erupted. Of 584 third molars evaluated, 79% were not fully erupted at baseline; of 462 molars, 80% could not be probed at baseline. Eruption to the level of the occlusal plane occurred in all 4 strata although only a third of the unerupted molars reached the occlusal plane even in the younger subjects with the longer follow-up. Of 369 molars that could not be probed at baseline, approximately 35% could be probed at follow-up with the highest percentage of change in the older subjects with the longer follow-up (46%). Conclusions The anatomic position of third molars was not static over time even if subjects were greater than 25 years old. Thus, unerupted third molars should be monitored for changes in position and periodontal pathology as long as the teeth are retained.
Target detection from TVSS shallow-water data using a multichannel subband adaptive filtering scheme

In processing the Toroidal Volume Search Sonar (TVSS) data, the primary challenge is to detect targets in highly reverberant environments. This may be done by processing each sonar channel separately and estimating the time delays associated with the specular returns and then isolating these components from the background noise prior to beamforming. However, if there is significant reverberation it is difficult to accurately estimate time delays using only one sonar channel. Therefore, a multi-channel method is introduced that exploits the interdependency of adjacent sonar stave data. The method starts by enhancing signal to noise by combining multiple stave data after suitable phase compensation for array geometry. Next, time delays of the specular returns are estimated from the discrete wavelet sub-bands of the combined signal using a least squares method. The new method has been tested on several TVSS data sets, and the results are promising for even the most reverberant cases.
Isolated upright gastroesophageal reflux is not a contraindication for antireflux surgery.

Abstract Background. Patients with gastroesophageal reflux disease who reflux only in the upright position are thought to have a less severe abnormality. Controversy exists over whether these patients should be considered candidates for antireflux surgery. Methods. A total of 224 consecutive patients with increased esophageal acid exposure on 24-hour pH monitoring were classified as having upright (n = 54), supine (n = 72), or bipositional (n = 98) reflux and were evaluated by manometry and endoscopy. Of these, 116 patients had a laparoscopic Nissen fundoplication. Their clinical outcome at a median of 12 months (range 4 to 44 months) was compared. Results. Patients with upright reflux had a lower prevalence of a structurally defective lower esophageal sphincter, fewer hiatal hernias, and less esophageal injury when compared to those with bipositional reflux (p Conclusions. Patients with upright reflux have less complicated, earlier disease and have results equivalent to those patients with supine and bipositional reflux after antireflux surgery.
On the architecture of regulatory systems: evolutionary insights and implications.

Interspecific comparisons reveal remarkable diversity in patterns of gene expression, even among closely related species. Combinatorial regulatory mechanisms could facilitate the evolution of this diversity. However, the high degree of interdependence characteristic of combinatorial networks would represent a major constraint on evolution and might generate many features that have no direct adaptive value.
Influence of monitor luminance and tone scale on observers' search and dwell patterns

The goal of this study was to measure the influence of monitor display luminance and tone scale on diagnostic performance and visual search behavior. Radiologists viewed 50 pairs of mammograms in two experiments. The first experiment changed the monitor's tone scale from its default (non-linearized) scale to the DICOM Barten scale (perceptually linearized). The second study compared an 80 ftL with a 140 ftL monitor. Eye- position was recorded. Performance with the Barten was higher than with the default curve. Performance with the 140 ftL was higher than with the 80 ftL monitor. Viewing time did not differ for tone scale, but was significantly shorter for 140 ftL vs 80 ftL. The number of fixation clusters generated was higher for the 80 ftL and the default tone scale. The difference was significant for lesion-free images. Median decision dwell times were longer in the default and 80 ftL conditions. Display luminance and tone scale affect diagnostic and search performance when using monitors. Lower luminance levels and a non-linearized display prolong search and recognition of normal, lesion-free areas compared to lesion- containing areas -- radiologists are having more trouble deciding that areas are truly normal. It is recommended that such factors as monitor luminance and choice of tone scale be taken into account when deciding to use CRT monitors for viewing radiographic images in the clinical environment.
Student-generated personality scales

A laboratory exercise, based on Jackson’s (1975) procedure, was developed in which four groups of undergraduates each generated a rationally derived, 10-item personality scale to measure one of four personality traits. Student responses on these and corresponding scales from Jackson’s (1974) Personality Research Form (PRF) were correlated with self-ratings and peer ratings of the students. The median validity (i.e., scale-rating correlation) for the student-generated scales was .42, compared with .55 for the PRF scales; however, the PRF scale accounted for an appreciably larger proportion of the criterion rating variance than did the corresponding student scale in only 6 of the 16 comparisons. The results generally were consistent with past work demonstrating the validity of student-generated, rationally derived scales of personality. Furthermore, the exercise proved useful in illustrating principles of item analysis and scale validation for the participating students.
A novel whole-embryo culture model for pharmaceutical and developmental studies.

Abstract Introduction This report introduces a new vertebrate whole-embryo culture model for the direct application of pharmaceuticals and/or toxins into developing embryos. This method uses a terrestrial amphibian system and therefore has eliminated the problem of mammalian placental and uterine concerns. To test the utility and effectiveness of this method, we investigated the effect of fluoxetine on craniofacial development. Fluoxetine is one of the most commonly prescribed selective serotonin reuptake inhibitor (SSRI) on the market and treatment of depression during pregnancy is commonly deemed necessary. Previous studies have shown that SSRIs may promote developmental defects and congenital malformations of the heart. Methods This model utilized the egg/embryos of the directly developing Puerto Rican coqui frog, Eleutherodactylus coqui. The E. coqui embryo clutches were placed on filter paper in a Petri dish and were directly exposed (chronically) to fluoxetine concentrations ranging from 0.10 mM to 1.0 mM. Traditional whole-mount bone (Alizarin red) and cartilage (Alcian blue) staining was utilized to show the effect of fluoxetine on craniofacial development. Results Whole-mount staining revealed profound defects in cartilage development, particularly in the nasal capsule, mandible, and the brain case. Further, fluoxetine-treated embryos developed significantly slower compared to control animals. Discussion We found that the E. coqui culture model was an effective and sensitive technique for pharmaceutical studies, particularly since it allows the direct application of drugs and toxins into the developing embryo without the hindrance of the uterus and placenta. Chromatographic analysis revealed that fluoxetine infiltrated and penetrated embryonic tissue. It was found that altering serotonergic activity during development, via fluoxetine, stunted craniofacial development and organization.
The microsomal mixed function oxidase system of amphibians and reptiles: components, activities and induction

Abstract This article reviews current research in amphibian and reptilian cytochromes P450, important to the overall understanding of xenobiotic metabolism in the ecosystem and the evolution of P450s. Amphibians and reptilians contain the normal mixed function oxidase system (MFO). In general the MFO content and activities are less than those found in mammals, but only a few of the known activities have been examined in these vertebrate classes. Research to date has focused on two families of cytochromes P450, CYP1 and 2. The isoforms examined catalyze the classic activities but there have been notable absences. The total number of isoforms present and the breadth of substrates metabolized are yet unknown. Induction by foreign compounds (xenobiotics) is lengthier and yields lower levels of induced activity than is typically found in mammals. When these animals are pretreated with 3-methylcholanthrene (3MC) and β -naphthaflavone (BNF), which are known to induce the same isoform in mammals, multiple isoforms are induced with different activities. Phenobarbital-pretreatment in turtles and alligators induces cytochromes P450 and suggestive data indicates induction in the lizard Agama lizard and the newt Pleurodeles waltl . In amphibians and reptiles a CYP2B protein does appear to be present along with constitutive activities associated with the 2 family of cytochromes P450. The markedly different response to classic inducers combined with lower or absent activities alters the view of how amphibians and reptilians respond to xenobiotic challenges.
The effect of recombinant growth hormone on the strength of ileal anastomoses in a rat model

In gynecologic surgery, the ileum is the primary site of bowel injury. Recombinant growth hormone (rGH) has been shown to improve the strength of colonic anastomoses in experimental models. The purpose of this study is to evaluate the effect of rGH on small bowel anastomoses, specifically in the ileum. Twenty large female rats underwent segmental ileal resections and end-to-end ileoileostomies. The rats were randomized to be treated for 7 postoperative days with either rGH (2.0 mg /kg /day) or placebo starting on the day of surgery. On the seventh postoperative day, a segment of ileum surrounding the anastomosis was resected. The anastomoses were tested for breaking strength on a tensiometer and for tissue concentrations of hydroxyproline. The ileal anastomotic breaking strength in the rGH group was 163.5 ± 6.0 g (mean ±standard error). In the placebo group, the breaking strength of ileal anastomoses was 125.0 ± 3.0 g (P <.001). No significant difference was demonstrated with respect to the hydroxyproline concentration between the rGH group (15.2 ± 2.0 μg/mg) and the placebo group (14.6 ± 1.0 μg/mg). In an animal model, a 31% increase in ileal anastomotic breaking strength was induced by rGH administration. With further research this may translate into decreases in the surgical complications that occur in ileal anastomoses. Furthermore, these serve as preliminary data to a study that evaluates the effect of rGH on ileal anastomoses in radiation-injured bowel.