cssi/SciSciGPT-SciSciNet huggingface dataset:
PepT1 expressed in immune cells has an important role in promoting the immune response during experimentally induced colitis

We and others have shown that the dipeptide cotransporter PepT1 is expressed in immune cells, including macrophages that are in close contact with the lamina propria of the small and large intestines. In the present study, we used PepT1-knockout (KO) mice to explore the role played by PepT1 in immune cells during dextran sodium sulfate (DSS)-induced colitis. DSS treatment caused less severe body weight loss, diminished rectal bleeding, and less diarrhea in PepT1-KO mice than in wild-type (WT) animals. A histological examination of colonic sections revealed that the colonic architecture was less disrupted and the extent of immune cell infiltration into the mucosa and submucosa following DSS treatment was reduced in PepT1-KO mice compared with WT animals. Consistent with these results, the DSS-induced colitis increase in colonic myeloperoxidase activity was significantly less in PepT1-KO mice than in WT littermates. The colonic levels of mRNAs encoding the inflammatory cytokines CXCL1, interleukin (IL)-6, monocyte chemotactic protein-1, IL-12, and interferon-γ were significantly lower in DSS-treated PepT1-KO mice than in DSS-treated WT animals. Colonic immune cells from WT had significantly higher level of proinflammatory cytokines then PepT1 KO. In addition, we observed that knocking down the PepT1 expression decreases chemotaxis of immune cells recruited during intestinal inflammation. Antibiotic treatment before DSS-induced colitis eliminated the differential expression of inflammatory cytokines between WT and PepT1-KO mice. In conclusion, PepT1 in immune cells regulates the secretion of proinflammatory cytokines triggered by bacteria and/or bacterial products, and thus has an important role in the induction of colitis. PepT1 may transport small bacterial products, such as muramyl dipeptide and the tripeptide L-Ala-gamma-D-Glu-meso-DAP, into macrophages. These materials may be sensed by members of the nucleotide-binding site-leucine-rich repeat family of intracellular receptors, ultimately resulting in altered homeostasis of the intestinal microbiota.
Radical diffusion limits to photoinhibited superresolution lithography

Photoinhibited superresolution (PInSR) lithography is a two-color, one-photon scheme that promises high throughput far-field patterning at deep subwavelength scales. The technique requires that active species are confined for some minimum time to the illuminated area where they are generated. We investigate here the extent to which this condition is met for published materials. Using spatial and temporal control of focused beams as well as fluorescence recovery after photobleaching (FRAP), we probe the dynamics of photoinhibition in the PInSR material system. Our results indicate fast out-diffusion of unreacted photoinhibitor from the submicron optical spot during the polymerization interval, resulting in uniform rather than structured inhibition. Published results are consistent with this mechanism, indicating that superresolved polymer confinement with PInSR has not yet been shown with structured inhibition. To address the issue, we propose modifications to the material and exposure to slow inhibitor out-diffusion and accelerate polymer gelation.
Determination of griseofulvin by time-resolved phosphorimetry

Abstract The phosphorescence lifetimes of griseofulvin and dechlorogriseofulvin are shown to be 0.11 sec and 1.16 sec, respectively. This tenfold difference is shown to enable the use of time-resolved phosphorimetry for the determination of griseofulvin in mixtures with dechlorogriseofulvin.
Compositional decoupling of savanna canopy and understory tree communities in Serengeti

Questions What is the pattern of compositional similarity for woody plants across the demographic bottleneck (i.e. canopy trees >2 m vs understorey trees <2 m) commonly observed in savannas? Does compositional similarity between woody plants in the canopy and understorey change across environmental gradients, and if so, which resource or disturbance factors explain the pattern? Finally, does disturbance history, i.e. whether individuals are newly established seedlings or top-killed resprouts, help to explain the compositional similarity between canopy and understorey woody plants across sites? Location The Serengeti ecosystem, Tanzania, East Africa. Methods We compared the observed similarity to that expected from a simulated null model, and investigated the association between compositional similarity and soil bulk density, mean annual rainfall, fire return interval and elephant damage using a model selection approach. Moreover, we asked if disturbance history, i.e. whether individuals were newly established seedlings or top-killed resprouts, helped explain compositional similarity between the canopy and understorey. Results The composition of canopy (>2 m) and understorey (<2 m) trees was surprisingly distinct: Acacia robusta (37.9%) and Acacia tortilis (23.7%) dominated the canopy, while Ormocarpum trichocarpum (43.0%) and Dichrostachys cinerea (19.6%) dominated the understorey. Compositional similarity between canopy and understorey woody plants generally decreased with soil bulk density, while for top-killed individuals there was support for an increase in compositional similarity with fire return interval. Conclusions Our results suggest that the similarity between the canopy and recruitment communities is primarily associated with soil factors. Our results also suggest that long fire return intervals (i.e. infrequent fires) lead to increased similarity between the composition of the canopy and the recruitment pool, suggesting that disturbance promotes heterogeneity in the community across demographic bottlenecks. Despite the prominent role that megaherbivores and disturbance play in driving structural changes in savannas, our results suggest that previously unreported but pervasive species decoupling across demographic bottlenecks is primarily driven by resource availability or other bottom-up constraints.
Lipid peroxidation and morphological changes in mammalian cells treated with the glutathione oxidant, diamide☆

Abstract Chinese hamster ovary cells treated with the glutathione oxidant diamide formed large amounts of lipid peroxide. This effect was greater at 18 °C than at 0 °C and was apparently not a direct consequence of glutathione oxidation because it occurred at concentrations well above those needed to oxidize cellular glutathione. The reagent was toxic at 18 °C but not at 0 °C and caused extensive blebbing in 50% of the treated cells at this temperature. Electron microscopic examination of rabbit polymorphonuclear neutrophils disclosed that diamide caused formation of a large, organelle-free bleb and a band of fibrogranular material. It also inhibited phagocytosis of yeast particles by these cells. These effects were reversed when the cells were incubated at 37 °C in the absence of diamide. The results indicate that, although diamide is relatively specific for glutathione under some circumstances, effects observed with intact cells under most experimental conditions may reflect processes other than oxidation of endogenous glutathione.
Samarium chemisorption on group-IV semiconductors

Note: Univ wisconsin,dept phys,madison,wi 53706. Franciosi, a, univ minnesota,dept chem engn & mat sci,minneapolis,mn 55455.ISI Document Delivery No.: SR778 Reference LSE-ARTICLE-1984-008doi:10.1103/PhysRevB.29.5611 Record created on 2006-10-03, modified on 2017-05-12
A Comparison between Markovian and Non-Markovian Closures in Simulations of Nonlinear Dynamos with Application to the Protogalactic Dynamo

Nonhelical magnetohydrodynamic (MHD) turbulence and the nonlinear dynamo are investigated numerically using two statistical closures: the direct interaction approximation, or DIA (Kraichnan), and the realizable Markovian closure, or RMC (Bowman et al.). The RMC is an approximate version of the DIA that can be used to simulate wider ranges of wavenumbers for longer stretches of time. In a controlled numerical experiment, it is found that the DIA and RMC lead to comparable results in simulations of the nonlinear dynamo. This helps justify the use of the RMC and other Markovian closures for the dynamo problem, thereby supporting the result of Pouquet, Frisch, & Leorat that an initially weak magnetic field grows up to rough equipartition with the kinetic energy on all scales. The result obtained by Pouquet, Frisch, & Leorat is also reproduced directly with a numerical DIA calculation. A separate DIA calculation produces k-3/2 spectra for steady state isotropic MHD turbulence, in accord with the physical arguments of Kraichnan. A rough preliminary calculation based upon the RMC suggests that the magnetic energy grows to approximately 6% of the kinetic energy during the collapse of the protogalaxy in the theory of Kulsrud et al. In a technical aside, a geometric algorithm is presented for calculating wavenumber-bin volume factors in three-dimensional closure calculations.
Dielectric relaxation study of hydrogen exposure as a source of two-level systems in Al2O3

Abstract An important question in the manufacture of superconducting electronics is how to control the two-level systems found in amorphous insulators. The present article shows that hydrogen has a marked impact on the two-level systems in thin films of reactively sputtered Al 2 O 3 , a standard tunnel oxide for Josephson junctions. The magnitude of dielectric relaxation current in Al 2 O 3 films, believed to be caused by two-level systems, is shown to increase monotonically with the flow rate of H 2 into the chamber during deposition. This points toward a potential need for controlling hydrogen during the manufacture of superconducting electronics utilizing Al 2 O 3 .
Verification tests in solid mechanics

Code verification against analytical solutions is a prerequisite to code validation against experimental data. Though solid-mechanics codes have established basic verification standards such as patch tests and convergence tests, few (if any) similar standards exist for testing solid-mechanics constitutive models under nontrivial massive deformations. Increasingly complicated verification tests for solid mechanics are presented, starting with simple patch tests of frame-indifference and traction boundary conditions under affine deformations, followed by two large-deformation problems that might serve as standardized verification tests suitable to quantify accuracy, robustness, and convergence of momentum solvers used in solid-mechanics codes. These problems use an accepted standard of verification testing, the method of manufactured solutions (MMS), which is rarely applied in solid mechanics. Body forces inducing a specified deformation are found analytically by treating the constitutive model abstractly, with a specific model introduced only at the last step in examples. One nonaffine MMS problem subjects the momentum solver and constitutive model to large shears comparable to those in penetration, while ensuring natural boundary conditions to accommodate codes lacking support for applied tractions. Two additional MMS problems, one affine and one nonaffine, include nontrivial traction boundary conditions.
The Limit of Spectator Interaction

In this paper I establish a normative limit of spectator interaction. I argue that attempts by non-participants (e.g. spectators) to affect the outcome of a contest, whether intended or merely foreseeable, are unsporting and ought to be discouraged because they undermine fairness, which is a fundamental premise of ideal competition. Because this is at odds with the participatory ethos of contemporary sports fanaticism (e.g. ‘12th man’ campaigns, visual distractions by spectators, etcetera) I anticipate several potential objections. I refute concerns that my thesis is empirically dubious; that it is impractical; that it is subordinate to financial considerations; that it is nullified by participant acquiescence; and that it is subordinate to spectator interests.
Technology assessment for clean energy technologies: The case of the Pacific Northwest

Abstract This study presents a technology assessment for clean power generation in the Pacific Northwest. Our goal is to incorporate clean production principles into the evaluation process for power alternatives. Two types of technologies are considered: one is for a renewable energy source (wind) and the other is for a traditional, fossil fuel based energy source (coal). The Analytical Hierarchy Process is used to assess the feasibility of both the wind energy and clean burning coal energy technologies. Criteria such as location, cost, feasibility, and availability are used for evaluations. For the wind energy, cost was determined to be the most important criterion when making a technology decision. For the SO2 emissions technology, the regenerative process was determined to be the best technology to scrub SO2 emissions from the air. Additionally, efforts towards renewable energy in Oregon should continue. Both federal and state governments offer tax credits that can help mitigate costs and facilitate the adoption of renewable energy options for power companies.
Low-Absorption Grating Beam Samplers

A development program involving the design, fabrication and testing of low-efficiency, low-absorption grating beam samplers is described. Two different basic designs were selected for development. The first design is a low-efficiency grating with a high reflectivity multi-layer dielectric coating. The second design is a "buried grating", which consists of a blazed grating under a ZnSe spacer layer, with a high reflectivity multilayer overcoat. The fabrication problems associated with each type of beam sampler are discussed. The comparison of experimentally measured absorptivity and efficiency with values obtained from computer cal-culations are presented. An additional effort currently underway to make very low absorptivity beam samplers by generating periodic refractive index variations in the dielectric stack is also discussed.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Nano-Structured Polymer Coatings for Ultraviolet Protection

Polymer materials such as Kevlar that are susceptible to UV degradation may be protected by appropriate coatings. We are using zinc oxide and titanium dioxide nanoparticles with an average particle size ranging from 25 to 70 nm. Five weight percent nanoparticles were dispersed in acrylic coatings, the dispersion is assisted by addition of a non-ionic surfactant, mechanical stirring and ultrasonication. The UV protective mechanism of nanoparticle-embedded coatings is theoretically explained using Mie theory. We estimated the minimum thickness of a 5 weight % nanoparticle-embedded coatings that is required to prevent the UV radiation from reaching the base of the substrate. Results obtained from nanoparticle-embedded acrylic-coated Kevlar fabric and neat acrylic-coated Kevlar fabric after exposure to UV radiation in QUV weatherometer show that the nanoparticle coating offers protection. UV-visible spectroscopy was used to obtain quantitative results.
Influencing student beliefs: The design of a "high impact" teacher education program

Abstract The purpose of the study was to investigate a teacher education program that has been documented as having strong influence on the teaching beliefs and subsequent actions of program graduates. Data collection included formal and informal interviews, non-participant observation, and document analyses. The results indicate that the following nine program features are logical candidates for explaining why students appear to retain the influence of the program: (a) thematic approach, (b) cohort groups, (c) constant programmatic reinforcement, (d) professional development courses, (e) professional conduct expectations, (f) progressive and compatible internships, (g) awareness of studentship, (h) faculty consensus, and (i) political involvement.
Aviator performance during day and night terrain flight

Terrain flying both day and night is now an Army Aviation tactical requirement. The present investigation compared terrain flight for Low Level (LL) and Nap-of-the-Earth (NOE) profiles for 1) day flight with the unaided eye, 2) night flight with the unaided eye, and 3) night flight using Night Vision Goggles. Data was acquired through use of the Helicopter In-flight Monitoring System (HIMS). The total set of in-flight measures for LL and NOE were analyzed separately with further analysis on the subsets of pilot control variables, and aircraft status variables. Multiple discriminant analysis techniques were used to determine which measures best discriminated between visual conditions.
The incidental learning of associative responses to given stimulus words.

Abstract : This study was undertaken as a test of the following hypothesis: the maintenance of a set to emit a given stimulus word will facilitate the incidental learning of its verbal associative responses. The set to emit the given stimulus word was developed in two stages. The subjects (Ss) first undertook to identify the given word as it was projected on a screen at successive levels of clarity. The Ss were then told to indicate when the already identified word appeared in a series of projected items. These items included a group of associates of the critical stimulus word along with associates having no apparent relationship to the given stimulus word. The results indicated significantly better retention of the associates of the given stimulus word than was the case for unrelated associates. The results appeared to support the experimental hypothesis. The interpretation is in terms of the concept of response priming and what the authors designate as the extent to which stimulus items elicit distinctive meaningful response patterns. (Author)
Yeast excision repair gene RAD2 encodes a single-stranded DNA endonuclease

IN eukaryotes nucleotide excision repair of DNA damaged by ultraviolet radiation requires several gene products; defects in this process result in the cancer-prone syndrome xeroderma pigmento-sum (XP) in humans1,2. TheRAD2 gene is one of at least seven genes indispensable for excision repair in the yeast Saccharomyces cerevisiae2, and its encoded protein shares remarkable homology with the XP group-G gene product3. Here we overproduce the RAD2-encoded protein in S. cerevisiae, purify it to near homogeneity, and show that RAD2 protein in the presence of magnesium degrades circular single-stranded DNA. The RAD2 endonuclease is specific for single-stranded DNA as it does not act on doublestranded DNA. Given the absolute requirement for RAD2 in the incision step of excision repair, our findings directly implicate RAD2 protein and its human homologue XPG protein as a catalytic component that incises the damaged DNA strand during excision repair. Furthermore, our results indicate that eukaryotes probably employ two distinct endonuclease activities to mediate the dual incision at the damage site.
Consumer information‐seeking behaviour in the travel decision‐making process

One popular tourism promotional medium available to tourism destination marketing organizations is destination-specific travel information packages made available to potential visitors upon request. This paper discusses the importance of the tourist-directed information package as a promotional tool. The findings of this study indicate significant differences between information-seeking tourists and non-information-seeking tourists with regard to their socio-economic and vacation travel characteristics.
Control of ribonucleic acid function by oligonucleoside methylphosphonates

Resume Les oligodesoxyribonucleosides methylphosphonates contiennent des liaisons internucleotidiques methylphosphonates non ioniques liees en 3′–5′ a la place des liaisons phosphodiesters chargees normales des acides nucleiques naturels. Ces oligomeres sont resistants a l'hydrolyse nucleasique, ils peuvent passer a travers les membranes de cellules de mammiferes en culture et peuvent former des complexes stables a liaisons hydrogene avec les sequences nucleotidiques complementaires des RNA cellulaires, tels que les RNA messagers. Ces oligomeres sont facilement synthetises sur des supports polymeriques insolubles. Leur longueur de chaine et leur sequence nucleotidique peuvent etre determinees par des processus chimiques. Les oligonucleosides methylphosphonates complementaires de l'extremite 5′, de la region du codon d'initiation, ou de la region codante du mRNA de globine de lapin, inhibent la traduction du RNA messager dans les lysats de reticulocytes de lapin ainsi que la synthese de la globine dans les reticulocytes de lapin. Cette inhibition provient de l'interaction entre les oligomeres et le RNA messager et l'importance de l'inhibition est influencee par la structure secondaire du RNA messager ainsi que par la localisation des sites d'attachement de l'oligomere sur cet RNA. Les oligomeres complementaires des regions des codons d'initiation des mRNA des proteines N, NS et G du virus de la stomatite vasculaire (VSV) inhibent la synthese de proteines virales dans des cellules L de souris infectees par le VSV. Ces oligomeres n'affectent ni la synthese des proteines ni la croissance des cellules L. La synthese et la croissance de ces proteines virales peuvent egalement etre selectivement inhibees par les oligonucleosides methylphosphonates complementaires des sites d'epissages du donneur ou de l'accepteur du pre-mRNA viral. Un oligomere complementaire du site d'epissage du donneur du mRNA du grand antigene T de SV40 inhibe la synthese de l'antigene T dans les reins de singes verts africains infectes par SV40, mais n'inhibe pas la synthese des proteines cellulaires totales. Un oligomere complementaire des sites d'epissages des mRNA 4 et 5 precoces du virus de l'Herpes simplex type 1 reduit la production virale de deux unites log chez des cellules Vero infectees par HSV-1 et HSV-2. Cet oligomere n'affecte pas la viabilite des cellules Vero. Les resultats de ces etudes suggerent que les methylphosphonates oligodesoxyribonucleosides peuvent etre utilises pour controler de facon specifique l'expression des genes dans les cellules vivantes en intervenant dans la traduction ou dans l'epissage du RNA messager. Etant donne que la specificite de ces composants reside dans leur capacite a se lier aux sequences complementaires d'acide nucleique, il devrait etre possible de construire des oligomeres pouvant etre utilises pour sonder et peut-etre pour controler la fonction de proteines specifiques dans des cellules normales, transformees, ou infectees par un virus.
Community child health in crisis

Commentary on the leading article by Mather (see pp 697–704) In her personal view, Dr Mather has hit the nail on the head when she describes the world as currently viewed by many community paediatricians.1 On the one hand, most paediatricians who hold a post with the word “community” somewhere in their title or job description would talk enthusiastically about the uniquely varied, challenging, and frequently rewarding nature of their clinical work. However, they will also readily identify and expand on the frustrations, anxieties, and challenges identified within the paper. Community child health does appear to have somewhat of an image problem. It can be difficult to describe in a few sentences to a layperson what it is exactly that community paediatricians do. Colleagues in other braches of child health would have no difficulties in this respect and would accurately convey an easily understood image of their profession by saying “I look after sick newborn babies” or “I am a children’s doctor who specialises in diseases of the nervous system”. I challenge any community colleague to summarise their work in a similar fashion without resorting to such jargon as “social paediatrics”, “health promotion”, or “child advocacy”, terms which, though admirable in their own right, do not easily lend to an appreciation of who community paediatricians are or of their unique contribution to child health and welfare. This confusion may not be limited to the public. I remember some years ago referring a child with chronic nephrotic syndrome to a tertiary …
PERSPECTIVES ON MECHANISMS OF GENE REGULATION BY 1,25-DIHYDROXYVITAMIN D3 AND ITS RECEPTOR

Abstract 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) functions as a systemic signal in vertebrate organisms to control the expression of genes whose products are vital to the maintenance of calcium and phosphorus homeostasis. This regulatory capability is mediated by the vitamin D receptor (VDR) which localizes at DNA sites adjacent to the promoter regions of target genes and initiates the complex events necessary for transcriptional modulation. Recent investigations using chromatin immunoprecipitation techniques combined with various gene scanning methodologies have revealed new insights into the location, structure and function of these regulatory regions. In the studies reported here, we utilized the above techniques to identify key enhancer regions that mediate the actions of vitamin D on the calcium ion channel gene TRPV6, the catabolic bone calcium-mobilizing factor gene RankL and the bone anabolic Wnt signaling pathway co-receptor gene LRP5. We also resolve the mechanism whereby 1,25(OH)2D3 autoregulates the expression of its own receptor. The results identify new features of vitamin D-regulated enhancers, including their locations at gene loci, the structure of the VDR binding sites located within, their modular nature and their functional activity. Our studies suggest that vitamin D enhancers regulate the expression of key target genes by facilitating the recruitment of both the basal transcriptional machinery as well as the protein complexes necessary for altered gene expression.
Fracto-Emission from Interfacial Failure

Fracto-Emission is the emission of particles and photons during and after fracture of materials. The observed emission includes electrons, negative and positive ions, neutral species in both ground states and in excited states, and visible photons. This emission can often serve as a sensitive probe of crack growth and may prove to be a useful tool for investigating molecular and microscopic events accompanying crack growth and for studying the details of failure modes in a variety of materials. Interfacial failure provides unique fracto-emission signals due to the extensive charge separation accompanying separation of dissimilar materials. Here we present the results of several recent studies of interfacial failure involving a variety of materials and relate them to electronic and mechanical processes accompanying failure.
The Effect of Incidental Conversation on Memory for Focal Colors

Plog, Stephen 1986a Group Mobility and Locational Strategies: Tests of Some Settlement Hypotheses. In Spatial Organization and Exchange: Archaeological Survey on Northern Black Mesa. Stephen Plog, ed. Pp. 187-223. Carbondale: Southern Illinois University Press. 1986b Patterns of Demographic Growth and Decline. In Spatial Organization and Exchange: Archaeological Survey on Northern Black Mesa. Stephen Plog, ed. Pp. 224-255. Carbondale: Southern Illinois University Press. 1986c Understanding Cultural Change in the Northern Southwest. In Spatial Organization and Exchange: Archaeological Survey on Northern Black Mesa. Stephen Plog, ed. Pp. 310-336. Carbondale: Southern Illinois University Press. Plog, Stephen, and Shirley Powell 1984 Patterns of Cultural Change: Alternative Interpretations. In Papers on the Archaeology of Black Mesa, Arizona, Vol. 2. Stephen Plog and Shirley Powell, eds. Pp. 209-216. Carbondale: Southern Illinois University Press. Powell, Shirley L. 1983 Mobility and Adaptation: The Anasazi of Black Mesa, Arizona. Carbondale: Southern Illinois University Press. Powell, Shirley, Peter P. Andrews, Deborah L. Nichols, and F. E. Smiley 1983 Fifteen Years on the Rock: Archae-
Utilization of purines by an HPRT variant in an intelligent, nonmutilative patient with features of the Lesch-Nyhan syndrome.

The patient, H.Chr.B., was among the first reported with hyperuricemia and central nervous system symptoms. He has been found to have a variant of hypoxanthine guanine phosphoribosyl transferase (HPRT; E.C.2.4.2.8) distinct from the enzyme present in patients with the Lesch-Nyhan syndrome. The patient had chroeoathetosis, spasticity, dysarthric speech, and hyperuricemia. However, his intelligence was normal and he had no evidence of self-mutilation. There was no activity of HPRT in the lysates of erythrocytes and cultured fibroblasts when analyzed in the usual manner. Using a newly developed method for the study of purine metabolism in intact cultured cells, this patient was found to metabolize some 9% of 8-14C-hypoxanthine, and 90% of the isotope utilized was converted to adenine and guanine nucleotides. In contrast, cells from patients with the Lesch-Nyhan syndrome were virtually completely unable to convert hypoxanthine to nucleotides. The patient's fibroblasts were even more efficient in the metabolism of 8-14C-guanine, which was utilized to the extent of 27%, over 80% of which was converted to guanine and adenine nucleotides. The growth of the cultured fibroblasts of this patient was intermediate in media containing hypoxanthine aminopterin thymidine (HAT), whereas the growth of Lesch-Nyhan cells was inhibited and normal cells grew normally. Similarly in 8-azaguanine, 6-thioguanine, and 8-azahypoxanthine, the growth of the patient's cells was intermediate between normal and Lesch-Nyhan cells. These observations provide further evidence for genetic heterogeneity among patients with disorders in purine metabolism involving the HPRT gene. They document that this famous patient did not have the Lesch-Nyhan syndrome.
Effect of stimulus modality and task complexity on discrimination and reversal learning in preschool children

Abstract Two form discrimination experiments involving the visual and tactual modalities were conducted on 3 to 4-year-old S s. Discrimination and reversal learning in the tactual modality were found to be more rapid than in the visual modality. It was hypothesized that the tactual modality facilitated S' s learning by imposing restraints that led S to attend to more subtle cues. When analogous restraints were imposed on the visual discrimination (i.e., S was required either to look at each discriminandum separately or to draw the discriminandum to be selected) visual reversal learning was significantly facilitated.
A Persistent Feature of Multiple Scattering of Waves in the Time-Domain: A Tutorial

The equations for frequency-domain multiple scattering are derived for a scalar or electromagnetic plane wave incident on a collection of particles at known positions, and in the time-domain for a plane wave pulse incident on the same collection of particles. The calculation is carried out for five different combinations of wave types and particle types of increasing geometrical complexity. The results are used to illustrate and discuss a number of physical and mathematical characteristics of multiple scattering in the frequency- and time-domains. We argue that frequency-domain multiple scattering is a purely mathematical construct since there is no temporal sequencing information in the frequency-domain equations and since the multi-particle path information can be dispelled by writing the equations in another mathematical form. However, multiple scattering becomes a definite physical phenomenon in the time-domain when the collection of particles is illuminated by an appropriately short localized pulse.
Liquation Cracking in Aluminum Welds

Liquation cracking in the partially melted zone (PMZ) of aluminum welds was studied. The PMZ is the region immediately outside the fusion zone where the material is heated above the eutectic temperature. Highly crack-susceptible alloys 2024 and 7075 were welded using gas-metal arc welding (GMAW) with filler metals 1100 and 4043, respectively. Circular-patch welds were made on 3.2 mm thick workpiece with full penetration, and single-pass welds were made on 9.5 mm thick workpiece with partial penetration. Liquation cracking was observed in all welds. Dualpass welds were also made on 9.5 mm thick workpiece, with overlapping between the penetration tips of the two partial-penetration passes made on the opposite sides of the workpiece. Liquation cracking was found in the first pass but not in the second pass. The results were explained using TfS (temperature vs. fraction solid) curves of the weld metal (WM) and the PMZ based on the following criterion proposed recently: liquation cracking can occur if WM fS > PMZ fS during PMZ solidification.
A longitudinal study of programmers' backtracking.

Programming often involves reverting source code to an earlier state, which we call backtracking. We performed a longitudinal study of programmers’ backtracking, analyzing 1,460 hours of fine-grained code editing logs collected from 21 people. Our analysis method keeps track of the change history of each abstract syntax tree node and looks for backtracking instances within each node. Using this method, we detected a total of 15,095 backtracking instances, which gives an average backtracking rate of 10.3/hour. The size of backtracking varied considerably, ranging from a single character to thousands of characters. 34% of the backtracking was performed by manually deleting or typing the desired code, and 9.5% of all backtracking was selective, meaning that it could not have been performed using the conventional undo command present in the IDE. The study results show that programmers need better backtracking tools, and also provide design implications for such tools. Keywords—empirical study; backtracking; undo; interactive development environments (IDE)
Analysis of Gas Purification by Pressure Swing Adsorption: Priming the Parametric Pump

Abstract The transients during start-up of a pressure-swing adsorber lead to material and energy losses. A dynamic mathematical model is developed to analyze the PSA process to elucidate the conditions under which losses may be minimized. It is based on an ideal binary mixture comprised of components that have linear isotherms. A processing alternative that virtually eliminates losses is suggested. The alternative is formulated by considering the PSA process as a specific type of parametric pump. It follows intuively that, as in an ordinary pump, the parametric pump will commence operation at steady-state if it is primed. In the case of PSA, that amounts to purging the initial adsorber contents with the less strongly adsorbed component. Illustrations are provided of both single-bed and dual-bed processes. For a specific gas mixture and adsorbent, the effect of varying the ratio of the high and low pressures that occur in a cycle is examined. Results indicate that there is a significant advantage in primin...
Coupling constants and vertex functions in string theories

We describe the structure of the vertex functions that must be inserted into the path integral for the S-matrix to describe the emission and absorption of general particles in bosonic string theories. The constant factors in these vertex functions and in the path integral itself are calculated in terms of the string tension and a single free coupling constant.
Acculturation and meanings of smoking among Asian--American college students.

Abstract We investigated meanings of smoking in white and Asian–American college students with different acculturation patterns. The associations between meanings of smoking and smoking behaviors were also examined. A survey was administered to two post secondary institutions in Southern California. A total of 460 Asian and 115 White students completed the survey. Results of this study demonstrate that the determinants of smoking may vary across cultural groups. A culturally appropriate smoking education curriculum tailored to different acculturation patterns and ethnicities is necessary.
Seasonal variations in the diurnal rhythm of pituitary prolactin content in the white-throated sparrow, Zonotrichia albicollis.

Abstract Marked diurnal rhythms of pituitary prolactin content occur both in May and in August. However, the phase of the rhythm with respect to the photoperiod differs at the two seasons. In May, the peak occurs at noon, but in August it occurs at midnight. It is concluded that the time of the diurnal release of pituitary prolactin is an important regulator of seasonal physiological and behavioral conditions in the White-throated Sparrow.
The Early History of the National Contest in Public Discussion.

More than 3,000 students have participated in the National Contest in Public Discussion, and more than 200 copies of the winning tapes have been distributed to colleges and universities that requested them for educational purposes. The finals of the annual contests have constituted sectional meetings at speech association conventions almost every year. The present article is the history of the Contest from its inception in 1951 through 1963.
Wave-Field Continuation and Decomposition for Passive Seismic Imaging Under Deep Unconsolidated Sediments

Abstract The coastal plains of the central and eastern United States contain deep sections of unconsolidated to poorly consolidated sediments. These sediments mask deeper crustal and upper-mantle converted phases in teleseismic receiver functions through large amplitude, near-surface reverberations. Thick sediments also amplify ambient noise levels to generally reduce data signal-to-noise ratios. Removing shallow-sediment wave-propagation effects is critical for imaging deep lithospheric structures. A propagator matrix formalism is used to downward-continue the wave field for teleseismic P waves into the midcrust and then to separate the upgoing S -wave field from the total teleseismic response of the P wave to expose deep Sp conversions. This method requires that the Earth model from the surface to the reference depth be known. Teleseismic P -wave data for the Memphis, Tennessee, station (MPH) are analyzed using a reference-station deconvolution technique to produce vertical and radial P -wave transfer functions. These transfer functions are modeled using a simple model parameterization for sediment structure through grid inversion. The inverted Earth model is incorporated into the wave-field continuation and decomposition technique to estimate the upgoing S -wave field at 10 km depth in the crust. Moho and possible deeper Ps conversions are identified with this process.
A Bayesian belief network (BBN) for combining evidence from multiple CO2 leak detection technologies

A Bayesian belief network (BBN) methodology is developed for integrating CO2 leak detection inferences from multiple monitoring technologies at a geologic sequestration site. The methodology is demonstrated using two monitoring methods: near-surface soil CO2 flux measurement and near-surface perfluoromethylcyclohexane (PMCH) tracer monitoring, from the Zero Emission Research and Technology (ZERT) release test in 2007. Statistical models are fitted to natural background soil CO2 flux and background PMCH tracer concentrations to determine critical levels for leak inference. Leakage-induced increments of soil CO2 flux and PMCH tracer concentrations are computed through TOUGH2 simulations for different leakage rates and subsurface permeabilities. The background characterizations and the simulation results are subsequently used to determine the conditional probabilities of leak detection in the BBN model. The BBN model is illustrated for use in evaluating the performance of alternative monitoring networks in a network design phase, and for combining inferences from multiple observations in the operational phase of a site. The detection capabilities of combined networks with different monitoring densities for soil CO2 flux and PMCH tracer concentration are compared. Given the test condition, the greater sensitivity of the PMCH tracer allows it to detect smaller leaks, while detection by the soil CO2 flux monitors implies that a larger leak is most likely present. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Solving propositional satisfiability problems

We describe an algorithm for the satisfiability problem of prepositional logic, which is significantly more efficient for this problem than is a general mixed-integer programming code. Our algorithm is a list processor using a tree-search method, and is based on Loveland's form of the algorithm of Davis and Putnam.
Homology between HL-23V and primate viruses and search for proviral DNA sequences of simian sarcoma associated virus and baboon endogenous virus in DNA from human leukemic cells.

Abstract A type C virus isolate (HL-23V) from leukemic cells is a mixture of baboon endogenous virus (BAV) and simian sarcoma associated virus (SSAV). There is 13% or less homology between BAV 30S RNA and SSAV 30S RNA. RNA (30S) isolated from HL-23 virions appears to consist only of BAV 30S RNA and SSAV 30S RNA. DNA from the spleen or peripheral blood leukemic cells of 25 different leukemia patients, DNA from the spleen, kidney or lung of 15 different patients with other neoplasias and DNA from normal tissues of 14 different individuals were examined for the presence of SSAV or BAV proviral DNA sequences. Cellular DNA excess hybridization to purified 3 H-labeled 30S viral RNA revealed that SSAV-RNA or BAV-RNA hybridized to the same extent with leukemic human DNA's and normal human DNA's.
Immune components in normal and inflamed human dental pulp.

Abstract Normal and inflamed human pulpal tissues were examined for the presence of humoral immune components. The results indicate that normal pulpal tissue is essentially devoid of components necessary for localized immunoglobulin synthesis as shown by the absence of any immunoglobulin-containing cells (ICC). Tissue fluorescence was observed only in the unwashed samples and mainly with the fluoresceinated IgG reagent. This fluorescence was essentially eliminated by prewashing prior to the application of the fluoresceinated antiserums. On the other hand, inflamed pulpal tissues showed the presence of various ICC. IgG ICC were preponderant, constituting more than 60 per cent of ICC observed. Significant numbers of IgA and IgE ICC were also observed in each sample examined; whereas IgM ICC were present in only 3 of 12 specimens. At the tissue level, fluorescence was observed both in unwashed and prewashed tissues, predominantly with the labelled IgG antiserum. The presence of ICC, as well as extracellular immunoglobulin in inflamed pulpal tissue suggests that the potential exists for immune mechanisms to contribute to the pathological periapical changes seen as sequelae to pulpal inflammation.
Thermo-acoustic instabilities in lean premixed swirl-stabilized combustion and their link to acoustically coupled and decoupled flame macrostructures

Abstract We investigate the onset of thermo-acoustic instabilities and their link to the mean flame configurations – or macrostructures – under acoustically coupled and decoupled conditions. Methane–hydrogen mixtures are used to explore the role of the fuel in changing the flame macrostructure, as determined by chemiluminescence, as the equivalence ratio ( ϕ ) varies. We observe four different configurations: a columnar flame (I); a bubble-columnar flame (II); a single conical flame (III); and a double conical flame (IV). We also observe different thermo-acoustic modes in the lean regime investigated, ϕ ∈ [ 0.5 - 0.75 ] , that correspond to different flame configurations. By changing the combustor length without affecting the underlying flow, the resonant modes of the combustor are shifted to higher frequencies allowing for the decoupling of heat release fluctuations and the acoustic field over a range of equivalence ratio. We find that the same flame macrostructures observed in the long, acoustically coupled combustor arise in the short, acoustically decoupled combustor and transition at similar equivalence ratios in both combustors. The onset of the first fully unstable mode in the long combustor occurs at similar equivalence ratio as the flame transition from configuration III to IV. In the acoustically decoupled case, this transition occurs gradually starting with the intermittent appearance of a flame in the outer recirculation zone (ORZ). Spectral analysis of this phenomenon, referred to as “ORZ flame flickering” shows the existence of an unsteady event occurring over a narrow frequency band centered around 28 Hz along with a weaker broadband region at lower frequency in the range [1–10] Hz. The tone at 28 Hz is shown to be associated with the azimuthal advection of the flame by the outer recirculation zone flow. Changes in the fuel composition, by adding hydrogen (up to 20%), do not affect the correspondence between the thermo-acoustic modes and the flame macrostructures, but shift the transition points to lower equivalence ratio.
Glacial Deposition Along an Ice‐Contact Slope: An Example from the Southern Lake District, Chile

Glacially derived sediments and structures vary systematically with topographic position along ice-contact slopes near the margin of former temperate piedmont glaciers in the southern Lake District, Chile. Features along lower positions of the slopes include glaciolacustrine sediments and large-scalethrusting. Middle slope features include low-angle subglacial thrusting of thin slices of lacustrine sediment. Upper slope features include high-angle thrusting, and lodgement and flow till. Locally, the same ordering of these features occurs in vertical sequence. A common theme that unifies the processes represented by these features is the distribution of hydrostatic pressure. Thicker ice (producing higher glacier overburden pressures) and aquicludes of fine-grained sediments toward the center of the basin result in high hydrostatic pressures, whereas thin ice and porous out-wash reduce these pressures at the top of the ice-contact slopes.However, such a distribution cannot completely explain the observed vertical sequences; hence, local variations in hydrostatic pressure because of lithologic contrasts probably play a role. Nowhere along the ice-contact slope are pervasively deformed glacial sediments observed; therefore they cannot be invoked to explain the low glacier profiles of these piedmont glacier lobes.
Estradiol-induced phosphorylation of ERK1/2 in explants of the mouse cerebral cortex: the roles of heat shock protein 90 (Hsp90) and MEK2.

Confocal laser scanning microscopy was used to identify the cells within organotypic slice cultures of the developing mouse cerebral cortex that respond to estradiol treatment by phosphorylation of ERK1 and ERK2. Estrogen-responsive cells resembled neurons morphologically and expressed the neuronal marker microtubule-associated protein 2B. The intracellular distribution of the phospho-ERK signal was both cytoplasmic and nuclear, but inhibition of protein synthesis abolished the appearance of the nuclear signal. ERK1and ERK2 also coimmunoprecipitated with heat shock protein 90 (Hsp90) in the cerebral cortical explants. Geldanamycin effectively disrupted this association and prevented ERK phosphorylation. Surprisingly, MEK2 but not MEK1 was the principal mediator of estradiol-induced activation of ERK. Our data demonstrate the requirement for Hsp90 in estrogen-induced activation of ERK1 and ERK2 by MEK2 in the developing mouse cerebral cortex and also provide insight into alternative mechanisms by which estradiol may influence cytoplasmic and nuclear events in responsive neurons via the MAP kinase cascade.
Cyclotron resonance of Si(001) inversion layers

Based on a memory-function formalism, the cyclotron data of Wagner, Kennedy, McCombe, and Tsui on inversion-layer electrons in Si metal-oxide---semiconductor field-effect transistors are analyzed. The cyclotron effective mass and the relaxation time of these electrons are evaluated as functions of density. Our theoretical results are found to be in good agreement with the data, if the impurity density is assumed to be 0.037 \ifmmode\times\else\texttimes\fi{} ${10}^{12}$ ${\mathrm{cm}}^{\ensuremath{-}2}$.