cssi/SciSciGPT-SciSciNet huggingface dataset:
Repetition in Conversation: A Look at "First and Second Sayings"

Repetition has been described as one of the most misunderstood phenomena in psycholinguistics (Ochs & Schieffelin, 1983). Indeed, repetition is a human, social activity, clearly part of our everyday conduct and behavior and not just a marker of a "disfluent" or "sloppy" speaker (Schegloff, 1987). Using the framework of conversation analysis, I discuss one form of repetition found in ordinary conversation, a form in which a speaker produces a "first saying" and, subsequent to that, a "second saying" within the same turn. Moreover, an inserted element comes between the first and second sayings. I propose that this particular form of repetition is used by speakers as a storytelling technique in the accomplishment of the action of resumption. What might be at stake in this form of repetition is something that might be referred to as unspoken repair (or unspoken repair projection). By extension, if one considers this form of repetition as an oral practice of everyday conversation (Hall, 1993), one might consid...
Comparison of viscous-shock-layer heating analysis with Shuttle flight data in slip flow regime

Comparison of STS-2 Shuttle flight heating data along the windward centerline has been made with two-dimensional nonequilibrium viscous shock-layer solutions obtained with shock and wall-slip conditions at an altitude range of 90 to 110 km. The shock slip condition used is the modified Rankine-Hugoniot relations of Cheng as used by Davis, and the wall-slip conditions are based on the first order consideration derived from kinetic theory as given by Scott and Hendricks. The results indicate that the calculated heating distributions with slip boundary conditions agree better with the flight data than those without slip conditions. The agreement improves when the accommodation coefficient or freestream density is decreased to one-half, suggesting the possibility of less than full accommodation for the tile surface and (or) an overestimate of freestream density using the Jacchia-Roberts model. Heating reduction due to the slip effect becomes very pronounced as the flow becomes more rarefied, and the effect is more significant for the stagnation region than the aft region of the vehicle.
Fiber Coupling Components

This paper reviews in a tutorial fashion the coupling of radiation from electrolumi-nescent sources into fiber waveguide transmission lines. A brief discussion of the splice coupling and data distribution components is also presented.© (1975) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Temporal patterns of uncoupling between oxidative metabolism and regional cerebral blood flow demonstrated by functional magnetic resonance imaging.

RATIONALE AND OBJECTIVES Brain activation can be detected by functional magnetic resonance imaging. Termination of stimulation can cause drop of postactivation signal below preactivation baseline; the nature of this "undershoot" remains controversial. The authors investigated postactivation signal after stimulation of the visual cortex with photic stimuli of different duration. METHODS Activation of visual cortex in 11 healthy subjects was studied. The authors underwent short and long stimulation. The relation between activation and postactivation signal was investigated after both durations of stimulation. RESULTS Average postactivation signal after short stimulation was -1.71 +/- 2.66% and after long stimulation 0.82 +/- 1.59% (P < or = 0.01). Significant "undershoot" was detected after short stimulation in the majority of cases, although this was typically absent after long stimulation. CONCLUSIONS The authors propose that "undershoot" is caused by decreased oxygen content in venous blood compared with the preactivation level and may reflect increased extraction of oxygen as a result of glycolytic metabolism. The absence of "undershoot" after longer stimulation suggests a gradual shift from uncoupling between regional cerebral blood flow and oxygen consumption toward a steady state.
Characterization of a Resting State Model of Peroxidases by ab Initio Methods: Optimized Geometries, Electronic Structures, and Relative Energies of the Sextet, Quartet, and Doublet Spin States

Ferric aquo heme complexes comprise the active site of three major families of heme proteins, the peroxidases, the cytochrome P450s, and metmyoglobin. There is ample evidence from a variety of spectroscopic studies of wild type (wt) and mutant enzymes that in these resting state complexes, the sextet, quartet, and doublet states are very close in energy and the predominant spin state observed is a sensitive function of the number, nature, and geometry of the axial ligands. One correlation that is very difficult to determine experimentally is the relationship between spin state and geometry in the same heme complex. This coupling of geometry and spin state in the same complex can be functionally important since spin state changes are often a key part of function, for example, in the enzymatic cycle of the cytochrome P450s. To further explore the relationship between geometry and spin state, we report here for the first time the use of ab initio methods to calculate optimized geometries and electronic struc...
Formation of Siphons in Lamellibranchia

THE mantle edge in the Lamellibranchia consists, as is well known, of three lobes. Of these the one adjacent to the shell (Fig. I, I) is concerned with the secretion of this, while the bounding periostracum is secreted as a thread from the base of the groove (PG) between this and the next lobe. This middle lobe (2) has sensory functions, bearing tentacles and in certain cases, for example, Pecten and Spondylus, eyes. The innermost lobe (3) is characteristically muscular. It contains radial muscles attached to the shell along the pallial line and, between upper and lower strands of these, other muscle running longitudinally. Action of these muscles, in conjunction with distension caused by pressure of blood, is responsible for the movements of this lobe, usually known as the velum or, better, the pallial curtain. By this means the entrance of water into the mantle cavity is controlled, for example, in Ostrea1. In extreme cases, such as Pecten and Lima, it also controls the direction in which water is expelled during the swimming movements2.
Response Set in the Measurement of Stimulation-Seeking.

The effect of social desirability response set on a measure of individual differences in stimulation—seeking—the Sensation-Seeking Scale—was studied in a 2 × 3 × 5 design consisting of factors of sex, instructions (fake good, fake bad, and control) and five subscales, with 15 undergraduate Ss per cell, making a total of 90 Ss. No significant effect of instructions was found, nor were any interactions of any variables significant. However, a significant (p < .01) main effect associated with sex was obtained, with males scoring significantly higher than females. In addition, a significant (p < .01) main effect of subscales was found, indicating significant variation among subscale means. It was concluded that response set, as aroused, was not a significant factor in this measure.
Investigation of rational syntheses of heteroleptic porphyrinic lanthanide (europium, cerium) triple-decker sandwich complexes.

The use of lanthanide triple-decker sandwich molecules containing porphyrins and phthalocyanines in molecular information storage applications requires the ability to attach monomeric triple decker...
Flow Through a Curved Duct Using Nonlinear Two-Equation Turbulence Models

Standard isotropic and nonlinear two-equation turbulence closures are employed to calculate the flow through a 90-deg rectangular duct. The models used include the two-layer k-e model, the k-ω model, and two nonlinear variants of the k-ω model based on quadratic and cubic constitutive relations, respectively. Comparisons of the computed results with the measurements show that the cubic nonlinear k-ω closure is the only model that successfully reproduces most of the experimentally observed features of both the mean flow and turbulence fields. This work demonstrates, for the first time, that near-wall, nonisotropic, two-equation models offer a promising alternative to Reynolds-stress transport closures for developing practical computational fluid dynamics methods able to predict complex shear flows of engineering interest.
The carceral aesthetic: Seeing prison on film during the early cinema period

This article examines how actuality and fictional films about prisoners made during the early cinema period construct a carceral imaginary that appropriated visual tropes from the Middle Ages while experimenting with motion picture’s unique signifying properties. The essay constructs a genealogy of prison-set motion pictures made before 1914, a period overlooked in standard prison film histories, starting with actualities of prisoners including The Lock Step (1899) and Female Prisoners: Detroit House of Corrections (1899), and fictional one-reelers Scenes of Convict Life (1905) and Children’s Reformatory (1907). Aspects of prison iconicity explored in this essay include the cell as a penitential but occasionally anarchic space, the lockstep and prison uniform, and the representation of escape. The trick film’s mocking of penal authority via the metamorphoses of convicts’ bodies in When Prison Bars and Fetters are Useless (1909) and the subversion of time in The Impossible Convicts, provides a potentially ...
Maintenance of Brine Transparency in Salinity Gradient Solar Ponds

Presentation des methodes de controle de la croissance d'algues dans les bassins solaires, dont la transparence est affectee. Description de la methode chimique (ajout de sulfate d'aluminium pour precipiter les phosphates solubles), de faible cout, utilisee dans un bassin solaire experimental de 1000 m 2 aux Etats-Unis et presentation des resultats obtenus
Laminin and Heparan Sulfate Proteoglycan Mediate Epithelial Cell Polarization in Organotypic Cultures of Embryonic Lung Cells: Evidence Implicating Involvement of the Inner Globular Region of Laminin β 1 Chain and the Heparan Sulfate Groups of Heparan Sulfate Proteoglycan

The extracellular matrix and in particular the basement membrane (BM) play an important role in the induction of organotypic rearrangement of cells in culture. This process involves cell aggregation, sorting into epithelial and mesenchymal components, epithelial cell polarization, and lumen formation. In this study, a combination of laminin (LM) and heparan sulfate proteoglycan (HSPG), two major BM constituents, induced organotypic rearrangement of embryonic mouse lung cells. In the absence of LM/HSPG supplementation, the cells sorted into epithelial and mesenchymal compartments but epithelial cell polarization and lumen formation did not occur. Neither LM nor HSPG alone could trigger this process. Synthetic peptide F-9, representing an amino acid sequence from the inner globular region of the laminin beta1 chain (RYVVLPRPVCFEKGMNYTVR) induced organotypic cell rearrangement when substituted for LM. Exogenous LM as well as peptide F-9 were localized at the epithelial-mesenchymal interface of organotypic cultures, where a BM-like structure is formed de novo. Organotypic cell rearrangement was blocked by heparin, heparan sulfate, or antibodies against peptide F-9. Binding assays indicated that peptide F-9 interacts with HSPG but not with LM or type IV collagen. Preincubation of embryonic lung cells with peptide F-9 resulted in a significant increase in cell attachment to HSPG but not to other major BM constituents. These findings suggest that the interaction between LM and BM HSPG is critical for the development of epithelial cell polarization and lumen formation. This interaction occurs at the epithelial-mesenchymal interface and is mediated by a site in the LM molecule represented by peptide F-9 and the heparan sulfate groups of HSPG.
Noninvasive diagnosis of pulmonary arterial hypertension in chronic obstructive pulmonary disease: right ventricular ejection fraction at rest.

Abstract Because right ventricular ejection fraction (RVEF) depends on impedance to RV ejection, the hypothesis was tested that an abnormality in radionuclide-determined RVEF would be a useful noninvasive predictor of pulmonary artery (PA) hypertension in patients with chronic obstructive pulmonary disease (COPD). Simultaneous measurements of resting RVEF and PA pressure were made in 30 patients with COPD. All were stable and without clinical evidence of respiratory decompensation or congestive heart failure. Eleven patients had normal ( 45%) and 25 patients depressed RVEF. An inverse linear relation between mean PA pressure and RVEF was present (r = −0.74). In the group with normal PA pressure, RVEF averaged 48% (range 42 to 60%). In the group with PA hypertension, RVEF averaged 36% (range 29 to 44%). RVEF was significantly higher in the group with PA hypertension. Using RVEF
Magnetic resonance imaging evaluation of recipient for cryopreserved aortic allograft

Aortic valve replacement with a cryopreserved aortic allograft is the procedure of choice for many patients with aortic valvular heart disease. We have used magnetic resonance imaging preoperatively to determine annular size and coronary artery orientation in the recipient, which not only has enabled us to select an allograft of appropriate size from a distant tissue bank, but also has helped us to identify preoperatively the recipient with a truly bicuspid valve in which the coronary arteries are oriented 180 degrees apart. Sixteen consecutive patients were evaluated preoperatively, the aortic annulus being measured with both magnetic resonance imaging and echocardiography. Cryopreserved aortic allografts were ordered on the basis of the magnetic resonance imaging measurement. Annular size was then measured intraoperatively with calibrated sizers. Magnetic resonance imaging annular measurements correlated highly with those found at operation (r = 0.92), whereas echocardiographic measurements correlated less well (r = 0.69). Coronary orientation was accurately predicted in every case (r = 1.0). Therefore, we have found magnetic resonance imaging to be useful in the preoperative evaluation of patients for aortic valve replacement with a cryopreserved aortic allograft.
Composition dependence of giant magnetoresistance in Fe/Ag/CoxFe1-x sandwiches

Abstract The magnitude of the giant or spin-valve magnetoresistance in ferromagnet/paramagnet/ferromagnet sandwiches depends on the choice of ferromagnet. In this study, the dependence of the giant magnetoresistance on the composition of the alloy layer in a series of Fe/Ag/CoxFe1-x sandwiches has been varied in order to get some insight into the fundamental origin of the effect. The CoxFe1-x alloy layers can be grown in the bcc phase throughout the range 0≤x≤1 using molecular beam epitaxy. The anisotropic magnetoresistance of these sandwiches shows a simple linear dependence on x, the Co fraction, but the giant magnetoresistance has a non-monotonic composition dependence.
Scaling of building affected plume rise and dispersion in water channels and wind tunnels—Revisit of an old problem

Abstract The high cost and site-specific results of field experiments have made water channels and wind tunnels important tools for the investigation of urban air quality. However, the applicability of laboratory studies depends on the correct scaling of the dominant physical properties. Simulation of the urban dispersion problems in laboratory facilities requires correct scaling of mean flow, plume rise, and turbulence governed plume spread. In this paper, a method for scaling the urban dispersion parameters in water channels and wind tunnels is presented. This method has been previously proposed and studied for the plume rise from isolated stacks; however, it has not been evaluated for cases of plume rise affected by surrounding buildings. Water channel experiments show that plume rise associated with relatively low-level buoyant sources in urban areas is highly affected by the complex flows induced by surrounding buildings, an effect which current plume rise models are not able to accurately reproduce. Based on these experiments, a new method for calculating the plume rise in urban areas, which accounts for the effect of surrounding buildings, is developed. The similarity of flow and plume rise, by matching the densimetric Froude number and relaxing initial density condition at the source, enables correct scaling of the concentration measurements from the laboratory to the field through the non-dimensional Gaussian dispersion model. This technique allows us to investigate the dispersion of buoyant emissions from low-level sources in urban areas through water channel or wind tunnel simulations. The sensitivity of this scaling technique under specific urban conditions is investigated.
Dynamic factorization in large-scale optimization

Factorization of linear programming (LP) models enables a large portion of the LP tableau to be represented implicitly and generated from the remaining explicit part. Dynamic factorization admits algebraic elements which change in dimension during the course of solution. A unifying mathematical framework for dynamic row factorization is presented with three algorithms which derive from different LP model row structures: generalized upper bound rows, pure network rows, and generalized network rows. Each of these structures is a generalization of its predecessors, and each corresponding algorithm exhibits just enough additional richness to accommodate the structure at hand within the unified framework. Implementation and computational results are presented for a variety of real-world models. These results suggest that each of these algorithms is superior to the traditional, non-factorized approach, with the degree of improvement depending upon the size and quality of the row factorization identified.
Chlordimeform: Uncoupling activity against rat liver mitochondria☆

Abstract The pesticide chlordimeform [ N′ -(4-chloro- o -tolyl)- N,N -dimethylformamidine] at 0.04 μmoles/mg protein uncouples 50% of respiratory-chain phosphorylation of rat liver mitochondria. This uncoupling activity depends on mitochondrial protein concentration and can be reversed either by the addition of bovine serum albumin or by washing. The normal inhibition of state 3 respiration by oligomycin and atractylate is completely reversed by chlordimeform. Uncoupling concentrations of chlordimeform elicit high adenosine triphosphatase activity. This activity is blocked by the above inhibitors of mitochondrial energy-transfer reactions. Evidence is presented which shows that unprotonated chlordimeform is the form effective in uncoupling. It is concluded that chlordimeform is an uncoupling agent with a potency and site of action close to but probably not identical to that of the classical uncoupler 2,4-dinitrophenol.
Implications of a scalar dark force for terrestrial experiments

A long-range intergalactic force between dark matter (DM) particles, mediated by an ultralight scalar, is tightly constrained by galactic dynamics and large scale structure formation. We examine the implications of such a ‘‘dark force” for several terrestrial experiments, including Eotvos tests of the Weak Equivalence Principle (WEP), direct-detection DM searches, and collider studies. The presence of a dark force implies a nonvanishing effect in Eotvos tests that could be probed by current and future experiments depending on the DM model. For scalar DM that is a singlet under the standard model gauge groups, a dark force of astrophysically relevant magnitude is ruled out in large regions of parameter space by the DM relic density and WEP constraints. WEP tests also imply constraints on the Higgs-exchange contributions to the spin-independent (SI) DM-nucleus direct-detection cross section. For WIMP scenarios, these considerations constrain Higgs-exchange contributions to the SI cross section to be subleading compared to gauge-boson mediated contributions. In multicomponent DM scenarios, a dark force would preclude large shifts in the rate for Higgs decay to two photons associated with DM-multiplet loops that might otherwise lead to measurable deviations at the LHC or a future linear collider. The combination of observations from galactic dynamics, large scale structure formation, Eotvos experiments, DM-direct-detection experiments, and colliders can further constrain the size of new long-range forces in the dark sector.
Antitumor efficacy and pharmacokinetic analysis of 4-hydroperoxycyclophosphamide in comparison with cyclophosphamide ± hepatic enzyme effectors

4-Hydroperoxycyclophosphamide is an oxazaphosphorine which is readily converted without enzymatic involvement to 4-hydroxycyclophosphamide-a key intermediate in the antitumor activity of this class of drugs. The efficacy of 4-hydroperoxycyclophosphamide as a systemically administered antitumor drug was examined in mice bearing EMT-6 mammary carcinoma and in rats bearing 13762 mammary carcinoma in comparison with other oxazaphosphorines. 4-Hydroperoxycyclophosphamide was a more potent tumor cell killing agent than cyclophosphamide or ifosfamide in animals bearing the EMT-6 tumor. There were no significant differences in the toxicity to bone marrow amongst the three oxazaphosphorines. 4-Hydroperoxycyclophosphamide (90 mg/kg) on days 7, 9 and 11 produced 11.5 days of tumor growth delay compared with 10.4 days and 7.1 days for cyclophosphamide (150 mg/kg) and ifosfamide (150 mg/kg) administered on the same schedule, respectively. 4-Hydroperoxycyclophosphamide was tolerated at 90 mg/kg daily for 5 days and at 75 mg/kg twice daily for 4 days producing tumor growth delays of 14.4 days and 16.6 days, respectively. In rats bearing 13762 tumors, 4-hydroperoxycyclophosphamide (90 mg/kg) on days 8, 10 and 12 produced a tumor growth delay of 14.5 days compared with 8.9 days for cyclophosphamide (100 mg/kg) administered on the same schedule. Treatment of 13762 tumor-bearing rats with phenobarbital, pentobarbital or etanidazole increased the tumor growth delay produced by cyclophosphamide while treatment with cimetidine decreased the tumor growth delay produced by cyclophosphamide but not significantly. Administration of 4-hydroperoxycyclophosphamide (90 mg/kg) produced blood concentrations of 4-hydroxycyclophosphamide three-fold higher than those produced by administration of cyclophosphamide (100 mg/kg) at 15 min after drug injection. Treatment with phenobarbital or pentobarbital increased 4-hydroxycyclophosphamide blood concentration while pretreatment with cimetidine decreased 4-hydroxycyclophosphamide blood concentration from cyclophosphamide. 4-Hydroperoxycyclophosphamide is an effective antitumor agent worthy of further investigation.
Conflicting effects of nitric oxide and oxidative stress in chronic heart failure: potential therapeutic strategies

Chronic heart failure (CHF) is characterized by decreased nitric oxide (NO) bioavailability. In addition, the beneficial NO turns to be deleterious when it reacts with superoxide anion, leading to peroxynitrite formation. Numerous experimental and clinical studies have reported increased production of reactive oxygen species (superoxide, hydrogen peroxide, hydroxyl radical) both in animals and patients with CHF. Moreover, there are indicative data suggesting mechanisms associated with endothelial dysfunction in states of CHF, mainly attributed to decreased NO bioavailability and enhanced inactivation of the latter. Thus, such molecules appear to be potential targets in patients with CHF. These patients are strong candidates to receive a variety of therapeutic agents, some of which have known antioxidant effects. Classic treatment with statins or angiotensin converting enzyme inhibitors has been found to be beneficial in restoring NO and improving myocardial function and structure. Other agents such as sildenafil and b-blockers along with novel agents such as NO synthase transcription enhancers have been proved to be also beneficial, but their use for such a purpose is still controversial. Approaches using more-effective antioxidants or targeting myocardial oxidant-producing enzymes and oxidative or nitrosative stress might be promising strategies in the future.
Durkheim's theories of deviance and suicide: a feminist reconsideration.

In the Division of Labor in Society, Durkheim conceptualizes deviance as an essentially asocial phenomenon, and the conceptualizes "woman" as an essentially asocial being. Both theories contradict Durkheim's characteristic social determinism, and both encounter, in Suicide, two further contradictions. First, Suicide demonstrates conclusively that relatively asocial individuals, women, are actually much less prone to deviance than relatively social individuals, men. Second, Suicide introduces the theory that deviance is an essentially social phenomenon that is produced by pathological social forces or "currents" rather than by "excessive individualization" and "insufficient socialization." Durkheim's second theory of deviance thus simultaneously rescues his theory of the social nature of men and his theory of the asocial nature of women.
Limited Awareness of Vaccines Recommended for Adolescents and Other Results from Two National Consumer Health Surveys in the United States

Abstract Purpose This study describes the vaccine-related knowledge and attitudes of adolescents aged 11–18 years and parents of adolescents aged 11–18 years. Methods We analyzed the 2007 HealthStyles and YouthStyles surveys related to vaccine knowledge and attitudes of parents (n = 1,208) and adolescents (n = 1,087). Results In all, 21% of parents and 11% of adolescents correctly identified the three vaccines recommended at the time of the survey for adolescents. Regarding the hypothetical scenario that minor adolescents should be allowed to consent to vaccination without parental knowledge, 70% of parents and 72% of adolescents disagreed. The majority of parents and adolescents recognized the importance of vaccines in protecting an adolescent's health yet a substantial minority of both groups also reported concerns about vaccine safety. Conclusions Many parents and adolescents surveyed were not aware of all vaccine recommendations for adolescents and did not support adolescents receiving vaccinations independent of parental knowledge and/or consent.
The burden of angina pectoris and its complications complications

Between 10 to 30% of patients with coronary disease still suffer from symptoms of angina pectoris in contemporary clinical practice. This article summarizes analytic tools for measuring angina, as well as, its prevalence based on community based surveys, registries and in randomized controlled trials. Additionally, the impact of angina symptoms on patients' survival rates, functional status, quality of life and health-related costs is reviewed. The effectiveness of treatment, revascularization and medical therapies, on reducing angina symptoms is also reviewed.
Complexity analysis of scalable motion-compensated wavelet video decoders

Scalable wavelet video coders based on Motion Compensated Temporal Filtering (MCTF) have been shown to exhibit good coding efficiency over a large range of bit-rates, in addition to providing spatial, temporal and SNR scalabilities. However, the complexity of these wavelet video coding schemes has not been thoroughly investigated. In this paper, we analyze the computational complexity of a fully-scalable MCTF-based wavelet video decoder that is likely to become part of the emerging MPEG-21 standard. We model the change in computational complexity of various components of the decoder as a function of bit-rate, encoding parameters such as filter types for spatial and temporal decomposition and the number of decomposition levels, and sequence characteristics. A key by-product of our analysis is the observation that fixed-function hardware accelerators are not appropriate for implementing these next generation fully scalable video decoders. The absolute complexity of the various functional units as well as their relative complexity varies depending on the transmission bit-rate, thereby requiring different hardware/software architecture support at different bit-rates. To cope with these variations, a preliminary architecture comprising of a reconfigurable co-processor and a general purpose processor is proposed as an implementation platform for these video decoders. We also propose an algorithm to utilize the co-processor efficiently.
Cerebral amyloid angiopathy and astrocytic gliosis in Alzheimer's disease

Astrocytic reaction at amyloid infiltrated cortical vessels was studied using glial fibrillary acidic protein (GFAP) stain in two cases of Alzheimer's disease (AD). Sections from the visual and prefrontal cortex were stained with HE there was no constant excessive gliosis around vessels with severe amyloid deposits. However, if amyloid infiltrating the vessel wall protruded into the perivascular neuropil of the cortex, then prolific reaction of astroglia, similar to that seen at interstitial senile plaques was apparent, and a neuritic component was distinct. It appears that once amyloid of AD type is deposited in the neuropil, whether in form of interstitial plaque or perivascular plaque, it causes a similar astroglial and neuritic reaction.
One plasmid selection system for the rapid evolution of aminoacyl-tRNA synthetases

We have developed a rapid, straightforward, one plasmid dual positive/negative selection system for the evolution of aminoacyl-tRNA synthetases with altered specificities in Escherichia coli. This system utilizes an amber stop codon containing chloramphenicol acetyltransferase/uracil phosphoribosyltransferase fusion gene. We demonstrate the utility of the system by identifying a variant of the Methanococcus jannaschii tyrosyl synthetase from a library of 10(9) variants that selectively incorporates para-iodophenylalanine in response to an amber stop codon.
HaND: Fast Handoff with Null Dwell Time for IEEE 802.11 Networks

How to reduce the handoff delay and how to make appropriate handoff decisions are two fundamental challenges in designing an effective handoff scheme for 802.11 networks to provide seamless and satisfactory data roaming services to mobile users. In this paper, we propose a unique fast handoff scheme called HaND (Handoff with Null Dwell time). HaND adopts a novel zero-channel-dwell-time architecture which leverages on the communication backbone between APs to relay the information about wireless channels, and allows the AP (rather than the station) to make appropriate handoff decisions aiming at providing fair service satisfaction to all stations. HaND is a software-only solution and compatible with the 802.11 standard without modifying the 802.11 protocol or introducing new wireless frames. We have implemented it in the Madwifi device driver and demonstrated its effectiveness via experiments.
Usability evaluation of web-based interfaces for Type2 Diabetes Mellitus

This study investigates and critiques existing Type 2 Diabetes Mellitus (T2DM) websites for usability concerns and provides design recommendations to improve it. A web search for T2DM and diabetes education based on Alexa and Google provided the basis for the study. A discounted usability evaluation technique, heuristic evaluation was applied. The heuristic evaluation resulted in 12 usability issues for American Diabetes Association (ADA) website; 11 usability issues for WebMD; and 15 usability issues for National Diabetes Education Program (NDEP) website. The top five usability problems were presented and discussed in detail. The site that had the best usability was ADA. Findings from this study will be essential for future research to assure that users have a great user experience with T2DM information websites and gain meaningful and relevant information on how to prevent the disease.
Complex length and persistence of limit cycles in a neighborhood of a hyperbolic polycycle

Complex limit cycle located in a neighborhood of a hyperbolic polycycle can not vanish under a small deformation that preserves the characteristic values of the vertexes of the polycycle. The cycles either change holomorphically under the change of the parameter, or come to the boundary of the fixed neighborhood of the polycycle. The present paper makes these statements rigorous and proves them.
The Strength of the Methodological Warrants for the Findings of Research on Program Evaluation Use

Considerable research has been conducted on the use of the findings of program evaluation, but little, if any, attention has been paid to the soundness of the methods of this research. If the methods are not sound or not well described in the research, the strength of the conclusions of the research is unknown. The authors examine the empirical studies reported in five widely cited reviews of the literature on program evaluation use and summarize the types of methods used, the professions for which they were conducted, and the extent to which they met two basic criteria for soundness. It was concluded that, by and large, the body of studies does not adequately address the criteria. With care, the findings of the research literature on the use of evaluations might provide guidance for evaluators, but they lack sufficient scientific credibility for other uses.
Oxygen surface exchange in mixed ionic electronic conductor membranes

Abstract We discuss the different oxygen surface exchange coefficients and the net surface exchange flux i=ciki0[exp(nμg/RT)−exp(2nμ/RT)] at gas–MIEC oxide interfaces, where ki=ki0(p/p0)n is the surface exchange coefficient, derived from isotope exchange experiments, p is the oxygen pressure, μg and μ are the chemical potentials of the gas and of the ion–electron hole pairs at the interface and ci is the oxygen ion concentration. The model is applied to oxygen permeation in planar and tubular membranes.
Genetic transformation of Ascochyta rabiei using Agrobacterium-mediated transformation

In order to study pathogenic mechanisms of the plant pathogen Ascochyta rabiei, conditions for efficient transformation using Agrobacterium-mediated transformation were investigated. Hygromycin B resistance (hph) was superior to geneticin resistance (nptII) for selecting transformants, and the hph gene was more efficiently expressed by the Aspergillus nidulans trpC promoter than by the Cauliflower mosaic virus 35S promoter CaMV35S. Co-cultivation on solid media for 72 h was optimal for generating transformants, but increasing the ratio of bacterial cells to conidia did not affect transformation efficiency. All hygromycin B-resistant transformants carried transfer-DNA (T-DNA) as determined by polymerase chain reaction (PCR) and the T-DNA integrations appeared to be random and in single copy as detected by Southern hybridization. Transformants remained resistant to hygromycin B in the absence of selection. Variations in colony morphology were observed in the presence of hygromycin B under different culture conditions, and a variety of altered phenotypes including reduced virulence were observed among 550 transformants. Inverse PCR was more efficient than TAIL-PCR in identifying flanking genomic sequences from T-DNA borders, and the possible causes are discussed. This transformation technique and recovery of flanking DNA using inverse PCR will provide a useful tool for genetic studies of A. rabiei.
Activation Barriers to Structural Transition Determine Deposition Rates of Alzheimer's Disease Aβ Amyloid

Abstract Brainamyloid composed of the ≈40-amino-acid human β-amyloid peptide Aβ is integral to Alzheimer's disease pathology. To probe the importance of a conformational transition in Aβ during amyloid growth, we synthesized and examined the solution conformation and amyloid deposition activity of Aβ congeners designed to have similar solution structures but to vary substantially in their barriers to conformational transition. Although all these peptides adopt similar solution conformations, a covalently restricted Aβ congener designed to have a very high barrier to conformational rearrangement was inactive, while a peptide designed to have a reduced barrier to conformational transition displayed an enhanced deposition rate relative to wild-type Aβ. The hyperactive peptide, which is linked to a heritable Aβ amyloidosis characterized by massive amyloid deposition at an early age, displayed a reduced activation barrier to deposition consistent with a larger difference in activation entropy than in activation enthalpy relative to wild-type Aβ. These results suggest that in Alzheimer's disease, as in the prion diseases, a conformational transition in the depositing peptide is essential for the conversion of soluble monomer to insoluble amyloid, and alterations in the activation barrier to this transition affect amyloidogenicity and directly contribute to human disease.
A modeled comparison of direct and food web-mediated impacts of common pesticides on Pacific salmon.

In the western United States, pesticides used in agricultural and urban areas are often detected in streams and rivers that support threatened and endangered Pacific salmon. Although concentrations are rarely high enough to cause direct salmon mortality, they can reach levels sufficient to impair juvenile feeding behavior and limit macroinvertebrate prey abundance. This raises the possibility of direct adverse effects on juvenile salmon health in tandem with indirect effects on salmon growth as a consequence of reduced prey abundance. We modeled the growth of ocean-type Chinook salmon (Oncorhynchus tshawytscha) at the individual and population scales, investigating insecticides that differ in how long they impair salmon feeding behavior and in how toxic they are to salmon compared to macroinvertebrates. The relative importance of these direct vs. indirect effects depends both on how quickly salmon can recover and on the relative toxicity of an insecticide to salmon and their prey. Model simulations indicate that when exposed to a long-acting organophosphate insecticide that is highly toxic to salmon and invertebrates (e.g., chlorpyrifos), the long-lasting effect on salmon feeding behavior drives the reduction in salmon population growth with reductions in prey abundance having little additional impact. When exposed to short-acting carbamate insecticides at concentrations that salmon recover from quickly but are lethal to invertebrates (e.g., carbaryl), the impacts on salmon populations are due primarily to reductions in their prey. For pesticides like carbaryl, prey sensitivity and how quickly the prey community can recover are particularly important in determining the magnitude of impact on their predators. In considering both indirect and direct effects, we develop a better understanding of potential impacts of a chemical stressor on an endangered species and identify data gaps (e.g., prey recovery rates) that contribute uncertainty to these assessments.
Role of Ca2+ in the Regulation of Nickel-Inducible Cap43 Gene Expression

We have recently cloned a gene, Cap43, that was significantly induced by exposure to nontoxic levels of both water-soluble and -insoluble Ni(2+) compounds. In this paper, we utilized the expression levels of this gene as a tool to identify second messengers involved in nickel-inducible transcription. We report here that the Ca(2+) ionophore A23187 substantially stimulated Cap43 gene expression. In addition, we found that BAPTA-AM, a specific chelator of free intracellular Ca(2+), consistently attenuated the induction of Cap43, indicating that elevation of intracellular Ca(2+) was essential for this response. TPEN, a chelator of heavy metals, such as Ni(2+) with a very low affinity for Ca(2+), did not attenuate Cap43 induced by Ni or calcium ionophore, suggesting that elevations of Ca(2+) but probably not elevations of other metal ions were involved in the induction of Cap43. A direct measurement of Ca(2+) levels using the fluorescent probe Fluo-3 AM showed elevations of free intracellular Ca(2+) in Ni-treated cells. A strong induction of Cap43 by okadaic acid suggested the involvement of a serine/threonine phosphorylation in a signaling pathway that was presumably activated by Ni and that led to enhanced Cap43 gene expression. However, calcium-dependent protein kinase(s) involved in the nickel-activated signaling pathway remains to be identified.
Decay of Nuclear Giant Resonance States Following Electroexcitation

Nucleon emission following inelastic electron scattering by a nucleus is described as a two-step process, in which a single isolated nuclear level is excited by the incident electron, and then subsequently decays to a state of the daughter nucleus by emitting a proton or neutron. General formulas are derived for the nucleon and electron angular distributions with the help of Racah algebra. Wigner $R$-matrix theory is then used to interpret the angular distributions in the reactions $^{12}\mathrm{C}(e,{e}^{\ensuremath{'}}p)^{11}\mathrm{B}$ and $^{16}\mathrm{O}(e,{e}^{\ensuremath{'}}p)^{15}\mathrm{N}$ with excitation of the $^{12}\mathrm{C}$ and $^{16}\mathrm{O}$ giant dipole states, as measured by Dodge and Barber.
Keeping at Arm’s Length during Regeneration

Regeneration of a lost appendage in adult amphibians and fish is a remarkable feat of developmental patterning. Although the limb or fin may be years removed from its initial creation by an embryonic primordium, the blastema that emerges at the injury site fashions a close mimic of adult form. Central to understanding these events are revealing the cellular origins of new structures, how positional identity is maintained, and the determinants for completion. Each of these topics has been advanced recently, strengthening models for how complex tissue pattern is recalled in the adult context.
Burkholderia glumae and B. gladioli Cause Bacterial Panicle Blight in Rice in the Southern United States

Bacterial panicle blight (BPB) is among the three most limiting rice diseases in Louisiana and the southern United States. The identity and characterization of pathogens associated with this disease was unclear. This research details studies carried out on the pathogens causing BPB on rice in Louisiana and other rice producing southern states. Bacterial strains were isolated from BPB-infected sheath, panicle, or grain samples collected from rice fields in Louisiana, Arkansas, Texas, and Mississippi. In greenhouse inoculation tests, 292 of 364 strains were pathogenic on rice seedlings or panicles. Identification of strains in the pathogen complex by growth on S-PG medium, carbon source utilization profile (Biolog), cellular fatty acid analysis, and polymerase chain reaction (PCR) methods revealed that 76 and 5% of the strains were Burkholderia glumae and B. gladioli, respectively. The other strains have not been conclusively identified. Although strains of both species produced similar symptoms on rice, B. glumae strains were generally more aggressive and caused more severe symptoms on rice than B. gladioli. Virulent strains of both species produced toxoflavin in culture. The two species had similar growth responses to temperature, and optima ranged from 38 to 40°C for B. glumae and 35 to 37°C for B. gladioli. PCR was the most sensitive and accurate method tested for identifying the bacterial pathogens to the species level. The 16S rDNA gene and 16S-23S rDNA internal transcribed spacer (ITS) region sequences of the B. glumae and B. gladioli strains from rice showed more than 99% sequence homology with published sequences. A real-time PCR system was developed to detect and quantify this pathogen from infected seed lots. Our results clearly indicate that B. glumae and B. gladioli were the major pathogens causing BPB in the southern United States.
Interview Practice U.S. Style: A Workshop for International Students.

The author describes a practice interview workshop customized for international graduate students. The session covered cultural and communication dynamics in the interview process, practice exercises, and a question-and-answer period.
Photochemical rearrangement of 8-oxabicyclo[3.2.1]oct-6-en-2-ones

Abstract Irradiation of 8-oxabicyclo[3.2.1]oct-6-en-2-ones results in a 1,3-acyl rearrangement. The initial photoproduct undergoes a subsequent reaction involving hydrogen transfer followed by intramolecular cycloaddition of a ketene intermediate.
Properties of compatibilized nylon 6/ABS blends. Part I. Effect of ABS type

Abstract Blends of nylon 6 with four acrylonitrile–butadiene–styrene (ABS) materials were investigated over a range of compositions using an imidized acrylic (IA) polymer as the compatibilizing agent. The IA material is miscible with the SAN matrix and is able to react with the amine end groups of nylon 6 during melt processing. The effects of ABS type and blend composition on the morphological, rheological and mechanical behavior of these blends were explored at a fixed (5 wt.%) compatibilizer content. In general, incorporation of the IA polymer can lead to super tough blends using a broad range of ABS materials. Of the ABS materials used, those with a monodisperse population of butadiene rubber particles and low melt viscosity were found to generate blends with superior low temperature toughness compared to those with broad particle size distributions and higher viscosity. In several compatibilized blends, increasing the ratio of nylon 6 to ABS improved the modulus and yield strength and did not significantly affect the room temperature impact strength up to a certain level; however, the ductile-to-brittle transition temperatures of these blends were quite sensitive to the amount of rubber in the blend, and increased steadily with increasing nylon 6/ABS ratio. The effect of compatibilizer content on blend properties was determined at a fixed ratio of nylon 6 to ABS. Super tough materials can be generated using very small (0.5 wt.%) amounts of the imidized acrylic polymer. Further increases in compatibilizer content did not significantly affect the room temperature impact strength, but did improve the low temperature toughness. When processing characteristics are considered, there is no justification to use more than about 2 wt.% of this compatibilizer.
Skin care management practices for premature infants.

OBJECTIVE: To describe current skin care practices for preterm infants in neonatal intensive care units in the United States. We hypothesized that there would be little consensus among facilities. STUDY DESIGN: Neonatal intensive care units (n = 823) listed in the 1996 United States Neonatologists Directory (American Academy of Pediatrics, Section on Perinatal Pediatrics) were sent a 28-question survey dealing with many aspects of neonatal skin care along with descriptive data about their neonatal intensive care unit. Descriptive data analysis was performed. RESULTS: A total of 305 surveys were returned (37% return rate); of these, 241 of the respondents reported admitting infants weighing ≤1000 gm. Some neonatal skin care practices showed wide consensus (>70%) (e.g., scrub procedure for staff; use of a skin barrier under tapes/adhesives), whereas other practices showed little consensus (<30%) (e.g., routine surveillance cultures; use of Aquaphor). CONCLUSION: Consensus on skin care practices was not found among neonatal intensive care units. Data from this survey can be used to develop studies to examine whether certain skin care management practices can improve neonatal outcomes.
The coding capacity of mismatched Gaussian channels (Corresp.)

Bounds on the coding capacity of Gaussian channels are obtained when the power constraint on the signal is mismatched to the channel noise. In the case of some feedback channels in which the noise has a Cramer-Hida representation of finite multiplicity, an exact expression for the coding capacity is given.
Ethics in Entertainment Television

(2004). Ethics in Entertainment Television. Journal of Popular Film and Television: Vol. 31, No. 4, pp. 146-148.
Incomplete inactivation and rapid recovery of voltage-dependent sodium channels during high-frequency firing in cerebellar Purkinje neurons

Purkinje neurons can spike very rapidly for sustained periods. We examined the cycle of sodium channel gating during high-frequency firing of Purkinje neurons, focusing on the kinetics of sodium ch...