bluuebunny/crossref_metadata_2025 huggingface dataset:
Location and dynamics of an active promoter in Escherichia coli K-12
Authors: Sánchez-Romero María-Antonia , Lee David J. , Sánchez-Morán Eugenio , Busby Stephen J. W.
Published: September 2011

In the present paper, we report that transcription affects the location of a DNA target in Escherichia coli K-12. A strain whose chromosome had been engineered to encode a lac repressor–GFP (green fluorescent protein) fusion was used as a host for a low copy number plasmid that carries an array of five lac operator sites. Individual cells of this strain exhibited a diffuse fluorescence signal, suggesting that the plasmid is distributed throughout the cell cytoplasm. However, a derivative of this plasmid carrying a cloned constitutive promoter is targeted to a location at the edge of the nucleoid towards the pole of the host cell. We conclude that transcription from the cloned promoter is driving the location of the plasmid and that specific locations in bacterial cells may favour gene expression.
The high-resolution crystal structure of periplasmicHaemophilus influenzaeNAD nucleotidase reveals a novel enzymatic function of human CD73 related to NAD metabolism
Authors: Garavaglia Silvia , Bruzzone Santina , Cassani Camilla , Canella Laura , Allegrone Gianna , Sturla Laura , Mannino Elena , Millo Enrico , De Flora Antonio , Rizzi Menico
Published: September 2011

Haemophilus influenzae is a major pathogen of the respiratory tract in humans that has developed the capability to exploit host NAD(P) for its nicotinamide dinucleotide requirement. This strategy is organized around a periplasmic enzyme termed NadN (NAD nucleotidase), which plays a central role by degrading NAD into adenosine and NR (nicotinamide riboside), the latter being subsequently internalized by a specific permease. We performed a biochemical and structural investigation on H. influenzae NadN which determined that the enzyme is a Zn2+-dependent 5′-nucleotidase also endowed with NAD(P) pyrophosphatase activity. A 1.3 Å resolution structural analysis revealed a remarkable conformational change that occurs during catalysis between the open and closed forms of the enzyme. NadN showed a broad substrate specificity, recognizing either mono- or di-nucleotide nicotinamides and different adenosine phosphates with a maximal activity on 5′-adenosine monophosphate. Sequence and structural analysis of H. influenzae NadN led us to discover that human CD73 is capable of processing both NAD and NMN, therefore disclosing a possible novel function of human CD73 in systemic NAD metabolism. Our data may prove to be useful for inhibitor design and disclosed unanticipated fascinating evolutionary relationships.
Electron dynamics and plasma jet formation in a helium atmospheric pressure dielectric barrier discharge jet
Authors: Algwari Q. Th. , O'Connell D.
Published: September 2011

The excitation dynamics within the main plasma production region and the plasma jets of a kHz atmospheric pressure dielectric barrier discharge (DBD) jet operated in helium was investigated. Within the dielectric tube, the plasma ignites as a streamer-type discharge. Plasma jets are emitted from both the powered and grounded electrode end; their dynamics are compared and contrasted. Ignition of these jets are quite different; the jet emitted from the powered electrode is ignited with a slight time delay to plasma ignition inside the dielectric tube, while breakdown of the jet at the grounded electrode end is from charging of the dielectric and is therefore dependent on plasma production and transport within the dielectric tube. Present streamer theories can explain these dynamics.
Impurity flows and plateau-regime poloidal density variation in a tokamak pedestal
Authors: Landreman M. , Fülöp T. , Guszejnov D.
Published: September 2011

In the pedestal of a tokamak, the sharp radial gradients of density and temperature can give rise to poloidal variation in the density of impurities. At the same time, the flow of the impurity species is modified relative to the conventional neoclassical result. In this paper, these changes to the density and flow of a collisional impurity species are calculated for the case when the main ions are in the plateau regime. In this regime, it is found that the impurity density can be higher at either the inboard or outboard side. This finding differs from earlier results for banana- or Pfirsch-Schlüter-regime main ions, in which case the impurity density is always higher at the inboard side in the absence of rotation. Finally, the modifications to the impurity flow are also given for the other regimes of main-ion collisionality.
Elastic wave propagation in a solid layer with laser-induced point defects
Authors: Mirzade Fikret
Published: September 2011

The results of the studies of the propagation of plane harmonic waves and vibrations in an isotropic, elastic solid layer with atomic point defects (interstitial atoms, vacancies, and electron-hole pairs) generated by a pulsed laser beam are presented. The study is based on coupled evolution equations for the elastic displacement of the medium and atomic defect density fields. The defect dynamics are governed by the strain-stimulated generation, diffusion, and annihilation processes. The frequency equations corresponding to the symmetric and antisymmetric elastic-concentration modes of vibration of the layer are obtained. Some limiting cases and special cases of the frequency equations are considered and a procedure for determining the phase velocity and the attenuation (or amplification) constants is discussed.
Multiple time scale molecular dynamics for fluids with orientational degrees of freedom. I. Microcanonical ensemble
Authors: Omelyan Igor P. , Kovalenko Andriy
Published: September 2011

We propose a new approach to eliminate the resonance instabilities inherent in multiple time step molecular dynamics simulations. The approach is developed within the microcanonical ensemble on the basis of an energy-constrained technique in the presence of orientational degrees of freedom. While the single and standard multiscale methods are restricted to small time steps of 5 and 8 fs, respectively, it is shown in simulations of water that the algorithms we have derived postpone the appearance of the instabilities to larger steps of about 16 fs. Such steps are close to the upper theoretical limit of 20 fs peculiar to the microcanonical ensemble and can be used without affecting static and dynamical properties.
A single centre water splitting dye complex adsorbed on rutile TiO2(110): Photoemission, x-ray absorption, and optical spectroscopy
Authors: Weston Matthew , Reade Thomas J. , Britton Andrew J. , Handrup Karsten , Champness Neil R. , O'Shea James N.
Published: September 2011

A single centre water splitting dye complex (aqua(2,2′-bipyridyl-4,4′-dicarboxylic acid)-(2,2′:6′,6′′-terpyridine)Ruthenium(II)), along with a related complex ((2,2′-bipyridyl-4,4′-dicarboxylic acid)-(2,2′:6’,6′′-terpyridine)chloride Ruthenium(II)), has been investigated using photoemission and compared to molecules with similar structures. Dye molecules were deposited in situ using ultra-high vacuum electrospray deposition, which allows for the deposition of thermally labile molecules, such as these dye molecules. Adsorption of the dye molecules on the rutile TiO2(110) surface has been studied using core-level and valence photoemission. Core-level photoemission spectra reveal that each complex bonds to the surface via deprotonation of its carboxylic acid groups. A consideration of the energy level alignments reveals that both complexes are capable of charge transfer from the adsorbed molecules to the conduction band of the rutile TiO2 substrate.
Electron-ion dynamics in laser-assisted desorption of hydrogen atoms from H-Si(111) surface
Authors: Bubin Sergiy , Varga Kálmán
Published: September 2011

In the framework of real time real space time-dependent density functional theory we have studied the electron-ion dynamics of a hydrogen-terminated silicon surface H-Si(111) subjected to intense laser irradiation. Two surface fragments of different sizes have been used in the simulations. When the intensity and duration of the laser exceed certain levels (which depend on the wavelength) we observe the desorption of the hydrogen atoms, while the underlying silicon layer remains essentially undamaged. Upon further increase of the laser intensity, the chemical bonds between silicon atoms break as well. The results of the simulations suggest that with an appropriate choice of laser parameters it should be possible to remove the hydrogen layer from the H-Si(111) surface in a matter of a few tens of femtoseconds. We have also observed that at high laser field intensities (2–4 V/Å in this work) the desorption occurs even when the laser frequency is smaller than the optical gap of the silicon surface fragments. Therefore, nonlinear phenomena must play an essential role in such desorption processes.
Optical gain characteristics of non-polar Al-rich AlGaN/AlN quantum well structures
Authors: Park Seoung-Hwan
Published: September 2011

Optical properties of non-polar Al-rich AlGaN/AlN quantum well (QW) structures were investigated using the multiband effective-mass theory and non-Markovian optical model with the many-body effect. These results are compared with those of the c-plane, i.e., the (0001)-oriented QW structures. The theoretical PL transition wavelength is found to agree well with the experimental result. The optical gain for the x′-polarization is much larger than that for the y′-polarization because the optical matrix element for the x′-polarization is larger than for the y′-polarization. The x′-direction in the non-poalr plane corresponds to c-axis direction. Also, the optical gain for the x′-polarization is shown to decrease with increasing Al composition. This is mainly attribute to the fact that the optical matrix element is decreased due to the reduction in the electron-hole overlap for QW structures with higher Al contents.
Highly mobile type II twin boundary in Ni-Mn-Ga five-layered martensite
Authors: Sozinov A. , Lanska N. , Soroka A. , Straka L.
Published: September 2011

Twin relationships and stress-induced reorientation were studied in Ni2Mn1.14Ga0.86 single crystal with five-layered modulated martensite crystal structure. Very low twinning stress of about 0.1 MPa was found for twin boundaries which deviated a few degrees from the (011¯) crystallographic plane. However, twin boundaries oriented exactly parallel to the (011¯) plane exhibited considerably higher level of twinning stress, above 1 MPa. X-ray diffraction experiments and calculations based on approximation of the martensite crystal lattice as a tetragonal lattice with a slight monoclinic distortion identified the two different kinds of twin interfaces as type II and type I twin boundaries.
Influence of localized electric field on the bandedge emission of hybrid Au-GaN/InGaN quantum wells
Authors: Gryczynski Karol G. , Rekha Vemuri Padma , Watson Ian , Neogi Arup
Published: September 2011

The modification in the bandgap of single GaN/InGaN quantum wells in the presence of a gold thin film with surface plasmon polariton energy off-resonant and resonant to the photoluminesnce emission energy is studied. The quantum well emission energy can be either blue shifted or red-shifted depending on the localized electric field induced by the metal thin film. A theory of electrostatic image charge induced alteration of the confinement potential is presented to explain the observed experimental shifts.
Chemical states and photoluminescence of Si0.3Ge0.7-nitride film formed by N2+ gas
Authors: Lee Y. M. , Jang S. H. , Han M. , Jung M.-C.
Published: September 2011

We investigated chemical states and photoluminescence of Si0.3Ge0.7-nitride film with a surface that was modified by N2+ ion implantation and rapid thermal annealing (RTA). By increasing the implantation time, the chemical bonding between Si and Ge was directly broken, and subnitrides were formed. We also observed the N2 vibration mode peak in the x-ray absorption spectra, but after RTA, this peak disappeared completely. SiNx was transformed to the stable Si3N4. However, GeNx with various chemical states, including Ge3N4 and nanocrystalline Ge, were formed. Photoluminescence observations at room temperature showed strong visible luminescence at wavelengths of 460 and 515 nm.
Large enhancement of the effective lifetime of n-type multicrystalline silicon by two step spin-on phosphorus diffusion and SiO2 passivation
Authors: Ben Jaballah A. , Moumni B. , Dhamrin M. , Saitoh T. , Kamisako K. , Bessais B.
Published: September 2011

A large improvement of the effective lifetime of n-type phosphorus doped multicrystalline silicon to reach 950 μs has been realized by combining both two step phosphorus treatments and surface oxidation. The average lifetime increases after the phosphorus diffusion process is mainly attributed to the remove of killer impurities which induces impurity gettering effects at the external surfaces. But an evident decrease of the electrical activity of some grain boundaries after that process was also observed due to the formation of heavily n+-type front layer of a floating junction and tunneling oxide along them. Moreover, low quality n-type substrates with an oxide passivated emitter are shown to suppress the effect of light induced degradation.
Band structure engineering and vacancy induced metallicity at the GaAs-AlAs interface
Authors: Upadhyay Kahaly M. , Nazir S. , Schwingenschlögl U.
Published: September 2011

We study the epitaxial GaAs-AlAs interface of wide gap materials by full-potential density functional theory. AlAs thin films on a GaAs substrate and GaAs thin films on an AlAs substrate show different trends for the electronic band gap with increasing film thickness. In both cases, we find an insulating state at the interface and a negligible charge transfer even after relaxation. Differences in the valence and conduction band edges suggest that the energy band discontinuities depend on the growth sequence. Introduction of As vacancies near the interface induces metallicity, which opens great potential for GaAs-AlAs heterostructures in modern electronics.
Presence of histone H3 acetylated at lysine 9 in male germ cells and its distribution pattern in the genome of human spermatozoa
Authors: Steilmann C. , Paradowska A. , Bartkuhn M. , Vieweg M. , Schuppe H. -C. , Bergmann M. , Kliesch S. , Weidner W. , Steger K.
Published: September 2011

During spermatogenesis, approximately 85% of histones are replaced by protamines. The remaining histones have been proposed to carry essential marks for the establishment of epigenetic information in the offspring. The aim of the present study was to analyse the expression pattern of histone H3 acetylated at lysine 9 (H3K9ac) during normal and impaired spermatogenesis and the binding pattern of H3K9ac to selected genes within ejaculates. Testicular biopsies, as well as semen samples, were used for immunohistochemistry. Chromatin immunoprecipitation was performed with ejaculated sperm chromatin. HeLa cells and prostate tissue served as controls. Binding of selected genes was evaluated by semiquantitative and real-time polymerase chain reaction. Immunohistochemistry of H3K9ac demonstrated positive signals in spermatogonia, spermatocytes, elongating spermatids and ejaculated spermatozoa of fertile and infertile men. H3K9ac was associated with gene promoters (CRAT, G6PD, MCF2L), exons (SOX2, GAPDH, STK11IP, FLNA, PLXNA3, SH3GLB2, CTSD) and intergenic regions (TH) in fertile men and revealed shifts of the distribution pattern in ejaculated spermatozoa of infertile men. In conclusion, H3K9ac is present in male germ cells and may play a role during the development of human spermatozoa. In addition, H3K9ac is associated with specific regions of the sperm genome defining an epigenetic code that may influence gene expression directly after fertilisation.
A nucleolar protein,
H19
opposite tumor suppressor (
HOTS
), is a tumor growth inhibitor encoded by a human imprinted
H19
antisense transcript
Authors: Onyango Patrick , Feinberg Andrew P.
Published: September 2011

The
H19
gene, which localizes within a chromosomal region on human chromosome 11p15 that is commonly lost in Wilms tumor (WT), encodes an imprinted untranslated RNA. However, the biological significance of the
H19
noncoding transcript remains unresolved because replacement of the RNA transcript with a neocassette has no obvious phenotypic effect. Here we show that the human
H19
locus also encodes a maternally expressed, translated gene, antisense to the known
H19
transcript, which is conserved in primates. This gene, termed
HOTS
for

H
19

o
pposite
t
umor
s
uppressor, encodes a protein that localizes to the nucleus and nucleolus and that interacts with the human enhancer of rudimentary homolog (ERH) protein. WTs that show loss of heterozygosity of 11p15 or loss of imprinting of
IGF2
also silence
HOTS
(7/7 and 10/10, respectively). Overexpression of
HOTS
inhibits Wilms, rhabdoid, rhabdomyosarcoma, and choriocarcinoma tumor cell growth, and silencing
HOTS
by RNAi increases in vitro colony formation and in vivo tumor growth. These results demonstrate that the human
H19
locus harbors an imprinted gene encoding a tumor suppressor protein within the long-sought WT2 locus.
Receptor for hyaluronan-mediated motility isoform B promotes liver metastasis in a mouse model of multistep tumorigenesis and a tail vein assay for metastasis
Authors: Du Yi-Chieh Nancy , Chou Chen-Kung , Klimstra David S. , Varmus Harold
Published: September 2011

The gene encoding the receptor for hyaluronan-mediated motility (RHAMM) is overexpressed in many human cancers. However, it is unclear whether RHAMM plays a causal role in tumor initiation or progression. Using somatic gene transfer in a mouse model of islet cell tumorigenesis, we demonstrate that RHAMM isoform B (RHAMM
B
) promotes tumor growth and metastases to lymph nodes and the liver. The propensity of RHAMM
B
-expressing cells to metastasize to the liver was confirmed using an experimental metastasis assay in which cells were injected into the tail vein of immunodeficient mice. However, RHAMM
B
did not increase cell migration or proliferation in culture. In initial efforts to identify signaling pathways activated by RHAMM
B
, we found that RHAMM
B
induced phosphorylation of epidermal growth factor receptor (EGFR), Erk1/2, and STAT3 and conferred susceptibility to apoptosis after treatment with an EGFR inhibitor, gefitinib. Taken together, the results indicate that RHAMM
B
promotes hepatic metastasis by islet tumor cells, perhaps through growth factor receptor-mediated signaling.
Modeling Regional Variation in Riverine Fish Biodiversity in the Arkansas–White–Red River Basin
Authors: Schweizer Peter E. , Jager Henriette I.
Published: September 2011

The patterns of biodiversity in freshwater systems are shaped by biogeography, environmental gradients, and human‐induced factors. In this study, we developed empirical models to explain fish species richness in subbasins of the Arkansas–White–Red River basin as a function of discharge, elevation, climate, land cover, water quality, dams, and longitudinal position. We used information‐theoretic criteria to compare generalized linear mixed models and identified well‐supported models. Subbasin attributes that were retained as predictors included discharge, elevation, number of downstream dams, percent forest, percent shrubland, nitrate, total phosphorus, and sediment. The random component of our models, which assumed a negative binomial distribution, included spatial correlation within larger river basins and overdispersed residual variance. This study differs from previous biodiversity modeling efforts in several ways. First, obtaining likelihoods for negative binomial mixed models, and thereby avoiding reliance on quasi‐likelihoods, has only recently become practical. We found the ranking of models based on these likelihood estimates to be more believable than that produced using quasi‐likelihoods. Second, because we had access to a regional‐scale watershed model for this river basin, we were able to include model‐estimated water quality attributes as predictors. Thus, the resulting models have potential value as tools with which to evaluate the benefits of water quality improvements to fish.
Soviet Perceptions of the Iranian Revolution
Authors: Akhavi Shahrough
Published: September 2011

Since the Iranian Revolution, Soviet writers have evidenced two general perceptions of that phenomenon. On the one hand, they perceive it as an anti-imperialist movement motivated by desires for socioeconomic development free of capitalist fetters. On the other hand, they cannot easily fit this revolution into the general theory of social change that is to be found in writings dating from Lenin and Stalin to more contemporary doctrines of the National Democratic State and the Revolutionary Democratic State.

This paper assesses the Soviet image of the Iranian Revolution by comparing and contrasting the arguments adopted by such theoreticians as Primakov, Stepaniants, Demchenko, Ulianovskii, Zagvozdkina, Vasil'ev, Timofeev, Nikol'skii, Trubetskoi, and others. They have tried to clarify the differences between what they term Islamic “orthodoxy” (fundamentalism), Islamic “reformism,” and Islamic “modernism.” In their view, the classification scheme is based on two factors: (1) the linkage of the movement to Islamic dogma; (2) the class basis of the movement.
Power of Ambiguity: Cultural Improvisations on the Theme of Temporary Marriage
Authors: Haeri Shahla
Published: September 2011

Law…is local knowledge; local not just as to place, time, class, and variety of issues, but as to accent--vernacular characterizations of what happens connected to vernacular imaginings of what can.

The objective of this paper is to describe cultural improvisations on the theme of temporary marriage, mut'a (sigheh in colloquial Persian) in Iran; I wish to bring to light the relationship between the law of the institution of temporary marriage, and certain common motifs of behavior of the Iranian people. I do not presume that the following is an exhaustive compilation of such improvisations; rather, it consists of those that I have been able to identify. While the terminology used is partly mine and partly indigenous, the descriptions of sigheh variations is entirely indingenous.
Ukrainian Nationalism and the 1918 Law on National - Personal Autonomy
Authors: Liber George
Published: September 2011

Traditionally in Eastern Europe, one national group constituted a majority in the countryside but a minority in the urban areas. Thus, while the cities of Eastern Europe possessed a disproportionate share of an area's political and socio-economic resources, for the most part they were ethnically alien to the peasantry. This was not a problem until the nineteenth century, which by 1914 turned Eastern Europe into a cauldron of inter-ethnic and anti-Semitic tensions. In the subsequent struggle for power, the national movements of both the urban and rural areas claimed the cities as well as the surrounding countryside. Inasmuch as these movements did not possess a common set of interests, whatever the proposed solution — whether territorial autonomy, irredentism, independence, expansion, or the maintenance of the status quo — hardly any provision was made for minority rights.
The Polish Peasant Movement and the Jews: The Polish Peasant Movement and the Jews, 1918-39
Authors: Wynot Edward W.
Published: September 2011

The relationship between peasant and Jew in Poland has presented a complex picture of mutual dependency and ambivalent feeling for centuries. Each needed the other for economic survival, yet simultaneously they often regarded each other with suspicion, mistrust, and, occasionally, loathing and fear. Nonetheless, until the emergence of a formally organized peasant movement in the late nineteenth century, it was extremely difficult to measure the actual perceptions and attitudes the peasantry held regarding the Jews. This essays traces the evolution of the stance toward the Polish Jews adopted by the peasant movement in the independent Polish Republic between the two world wars. It notes the passage of this stance from varieties of political indifference and economic concern through a phase of overt anti-Semitism, to the final stage of de-emphasizing the “Jewish Question” as a major factor in the political program and strategy of the movement.
The Nationality Question in Contemporary Hungarian-Romanian Relations
Authors: Knigth Gregory D.
Published: September 2011

The historical feud between Hungary and Romania over Transylvania has escalated in proportion and intensity in recent years. Territorial dispute is no longer central to the present debate. Rather, it is the treatment of approximately two million ethnic Hungarians residing in Transylvania that has generated considerable tension between the governments of Janos Kadar and Nicolae Ceausescu. Transylvania's ethnic Hungarians represent an obstacle to Ceausescu's policy of “national communism,” which promotes “Romanianism” to the detriment of the country's minority populations. In Hungary, reformists both within and outside the Kadar government have pressed the regime for a satisfactory solution to the perceived mistreatment of Hungarians living in neighboring socialist countries. By complicating relations between the two countries, the nationality question also effectively limits the degree to which Hungary and Romania can cooperate succesfully on regional endeavors. Finally, particularly in the case of Romania, exacerbation of the nationality question has attracted increased concern among “external” players, including the Soviet Union and the United States.
Trends in Judaism in the Soviet Union
Authors: Greenbaum Avraham
Published: September 2011

The history of Judaism in the Soviet Union is not a happy one. The Soviet Union, in a policy reminiscent of the premodern age, has persecuted the Jewish religion and not—with the exception of the 1948-53 period—Jews as persons. This does not mean that there was not discrimination. Anti-Jewish discrimination began about 1944 and presumably still continues in spite of Gorbachev's reported attempts to ease it. But we see no clear signs that the purges of the thirties were directed at Jewish party members as such. Recent research also does not credit the once common belief that the liquidation of the “Evsektsiia” (Jewish sections of the Communist party) in 1930 was an anti-Jewish act.
A Changing Economy in a Changing Society
Authors: Terk Erik
Published: September 2011

Changing through the Ages

Over different historical periods the Estonian economy has exhibited quite a different character in terms of its international context. To be more specific, we can mention the medieval flourishing of the free Hanseatic towns of northern Europe when Tallinn and other Estonian Hanseatic centers played an important role in trade between the east (Novgorod) and the west (basically towns of northern Germany and the Netherlands). Later, after an intervening period when Estonia was part of the Swedish Kingdom, it evolved as a western region of Tsarist Russia with its own specificity, somewhat different from the rest of Russia.
Estonian National Independence Party (ENIP)
Authors: Mäe Andres
Published: September 2011

The Estonian National Independence Party (ENIP) was founded on August 20, 1988, by former political prisoners, human rights activists, representatives of independent youth groups and intellectuals, at a risky time, when the political power in occupied Estonia was still monopolized by the communists.
Estonian Rural Center Party on Reforming Estonian Agriculture
Authors: Raig Ivar
Published: September 2011

Introduction

The Estonian Rural Center Party (ERCP) was established on April 7, 1990. It is participating in the international network of centrist parties and political movements (INC).
The Estonian Rural Union During the Restoration of Independence
Authors: Siredni Arvo
Published: September 2011

The Estonian Rural Union (Eesti Maaliit, EML) was created during the national independence struggle in 1917. The EML shared power in Estonia's inter-war independence period and was left in a state of oblivion during the occupation years. The party was revived first as a popular movement in 1989 and two years later as a political party.
Programming Plans and Programming Expertise
Authors: Gilmore D. J. , Green T. R. G.
Published: September 2011

This paper addresses issues of the nature of expertise in programming and asks whether “programming plans” represent the underlying deep structure of a program. It reports an experiment that investigated the effect, on experienced programmers, of highlighting the plan structure of a computer program, while they were performing both plan-related and unrelated tasks. The effect was examined in both Pascal and BASIC. For Pascal programmers, perceptual cues to the plan structure were useful only for plan-related tasks, but the same cues were of no benefit to experienced BASIC programmers in any of the tasks. These results suggest that the actual content of programming plans does not generalise across different languages, although it is possible that the BASIC programmers can use other plans. From these results a more detailed description of programming plans and their role in programming expertise can be developed. The fact that BASIC programmers were not sensitive to the same plans as Pascal programmers implies that plans cannot represent the underlying deep structure of the programming problem.
Movement and Working Memory: Patterns and Positions in Space
Authors: Smyth Mary M. , Pearson Norma A. , Pendleton Lindsay R.
Published: September 2011

Five experiments are reported in which subjects were asked to remember short, visually presented sequences of whole body movement patterns, words, and spatial positions. The items were recalled in order in a memory span paradigm. During presentation of the items to be remembered subjects simply watched, or they carried out a concurrent activity involving articulatory suppression, movement to external spatial targets, or body-related movement. When the movement patterns to be remembered were familiar to subjects, movement span was not disrupted by articulatory suppression or movement to spatial targets but was disrupted by body-related movement. This movement suppression task, however, did not interfere with performance on a spatial span task or on verbal span. It is concluded that the memory for patterns of limb movement differs from memory for movement to spatial targets and that accounts of visuo-spatial processes in working memory involve the latter type of movement.
Forced Revision in Fast Typing: A Note
Authors: Shaffer L. H.
Published: September 2011

Forced revision during transcription was brought about by having the text change suddenly at a preset distance ahead of the current motor output. The adaptiveness of the motor system to change was studied as a function of this trigger distance. Two out of five typists tested were able to assimilate the change with minimum disruption of typing fluency. The timescale of revision by these two appears to be within earlier estimates of the time course of motor programming in normal conditions. It shows some sensitivity to syntax, being larger if the change was triggered within the word rather than in the previous word.
The Double Step Analysis of Rapid Manual Aiming Movements
Authors: Barrett Nicholas C. , Glencross Denis J.
Published: September 2011

The present paper examines the control principles underlying rapid manual tracking responses to horizontal double-step stimuli. The paper reports an experiment concerned with responses made to step-stimuli presented in quick succession. The amplitude of the second-step was varied between the initial step-position and the home-base. Double-step response parameters were analysed as a function of the determinant time interval (D) between the second step and the onset of the initial response. The initial response amplitude was observed to vary as a function of D. Amplitude transition functions were constructed representing the transition of the initial response amplitude between the two step positions; their slopes, furthermore, depended on the amplitude of the second target step. No delays in the initial reaction time with the interstimulus interval were observed. Minor delays to the onset of a corrective response were observed. These delays were in part related to a movement time constraint that is independent of any limitations in central processing capacity. The present findings for the manual control system are compared to double-step tracking analyses of the oculomotor control system.
A Philosophical and Empirical Analysis of Subjects’ Modes of Inquiry in Wason's 2–4–6 Task
Authors: Tukey David D.
Published: September 2011

Investigations of hypothesis-testing behaviour typically conclude that subjects’ methods are characterized by “confirmation bias.” However, these studies (a) relied exclusively upon Karl Popper's philosophy of science, (b) only described subjects’ strategies via a falsificationist terminology, and (c) failed to determine subjects’ precise intentions in the task situations. Alternative philosophies of science can be used to describe hitherto ignored aspects of rule discovery in Wason's (1960) 2–4–6 task as well as reinterpret findings from previous research. Using Wason's task, Experiment 1 adopted J. S. Mill's inductive methodology in order to assess better the extent of elimination in experimentation. While it was found that subjects did eliminate a large proportion of their hypotheses rather than merely confirm them, Mill's eliminative methods applied to this task failed to account for the entirety of subjects’ behaviours. Experiment 2 examined subjects’ methods in more depth by asking subjects during the task either to: (1) describe their procedures, (2) select from a list of methodology terms those that best characterized their methods, and (3) state on each learning trial their preferred hypotheses and their subjective assessments that those hypotheses were correct. Although subjects were generally unable to describe their methods of inquiry, they were able to typify them via the methodology terms as if their methods were tacitly held skills. Contrary to presumptions of previous research, analyses indicated that subjects were not testing particular hypotheses on every trial but were often examining possible instances of the rule “at random” or “different from ones examined” to that trial. It is also suggested that subjects’ decisions to announce rules and their thematic lines of inquiry be given further consideration by researchers.
The Relationship between Eye Movements and Spatial Attention
Authors: Shepherd Martin , Findlay John M. , Hockey Robert J.
Published: September 2011

Most previous studies of the attentional consequences of making saccadic eye movements have used peripheral stimuli to elicit eye movements. It is argued that in the light of evidence showing automatic “capture” of attention by peripheral stimuli, these experiments do not distinguish between attentional effects due to peripheral stimuli and those due to eye movements. In the present study, spatial attention was manipulated by varying the probability that peripheral probe stimuli would appear in different positions, while saccades were directed by a central arrow, enabling the effects of attention and eye movements to be separated. The results showed that the time to react to a peripheral stimulus could be shortened both by advance knowledge of its likely position and, separately, by preparing to make a saccade to that position. When the saccade was directed away from the most likely position of the probe, the targets for attention and eye movements were on opposite sides of the display. In this condition, the effects of preparing to make a saccade proved to be stronger than the effects of attentional allocation until well after the saccade had finished, suggesting that making a saccade necessarily involves the allocation of attention to the target position. The effects of probe stimuli on saccade latencies were also examined: probe stimuli that appeared before the saccade shortened saccade latencies if they appeared at the saccade target, and lengthened saccade latencies if they appeared on the opposite side of fixation. These facilitatory and inhibitory effects were shown to occur at different stages of saccade preparation and suggest that attention plays an important role in the generation of voluntary eye movements. The results of this study indicate that while it is possible to make attention movements without making corresponding eye movements, it is not possible to make an eye movement (in the absence of peripheral stimulation) without making a corresponding shift in the focus of attention.
Digit Span, Reading Rate, and Linguistic Relativity
Authors: Naveh-Benjamin Moshe , Ayres Thomas J.
Published: September 2011

The relations between reading time and memory span were studied in four languages: English, Spanish, Hebrew, and Arabic. Reading rate was measured either in speeded reading of digits or in normal-pace reading of stories. Faster speeded reading and normal-pace reading rates for a given language were associated with larger memory span for speakers of that language. These relations, which were shown to be monotonically related to the number of syllables or phonemes per item, extend the within-language word-length effect reported by Baddeley, Thomson and Buchanan (1975), across languages. In addition, these findings demonstrate a form of linguistic relativity: a relation between simple surface-structural features of language (number of syllables) and cognitive processing (memory span and reading rate). It is argued that this linguistic relativity may be limited by trade-offs between surface features and common linguistic practice.
Repetition priming of face recognition
Authors: Ellis Andrew W. , Young Andrew W. , Flude Brenda M. , Hay Dennis C.
Published: September 2011

Three experiments investigating the priming of the recognition of familiar faces are reported. In Experiment 1, recognizing the face of a celebrity in an “Is this face familiar?” task was primed by exposure several minutes earlier to a different photograph of the same person, but not by exposure to the person's written name (a partial replication of Bruce and Valentine, 1985). In Experiment 2, recognizing the face of a personal acquaintance was again primed by recognizing a different photograph of their face, but not by recognizing the acquaintance from that person's body shape, clothes etc. Experiment 3 showed that maximum repetition priming is obtained from prior exposure to an identical photograph of a famous face, less from a similar photograph, and least (but still significant) from a dissimilar photograph.

We argue that repetition priming is a function of the degree of physical similarity between two stimuli and that lack of priming between different stimulus types (e.g., written names and faces, or bodies and faces) may be attributable to lack of physical similarity between prime and test stimuli. Repetition priming effects may be best explained by some form of “instance-based” model such as that proposed by McClelland and Rumelhart (1985).
Spatial Coordinates and Reading: Comments on Monk (1985)
Authors: Kennedy Alan , Murray Wayne S.
Published: September 2011

Subjects are able to process some texts when they are presented, word-by-word, in a single physical location. As differential spatial information is not available in this task, Monk (1985a) argues that it need not be derived in normal reading. We suggest this conclusion is unwarranted, because subjects make large and very accurate regressive saccades to regions of previously fixated text. Without a representation of spatial coordinates this should not occur.
Parsing Temporarily Ambiguous Complements
Authors: Rayner Keith , Frazier Lyn
Published: September 2011

Holmes, Kennedy and Murray (1987) recently claimed that the empirical support for the Minimal Attachment Strategy of sentence parsing had been weakened by results they reported. They found that reading time for an ambiguous string of words did not decrease when it was preceded by an overt complementizer, which should have disambiguated it. Thus, they suggested that results that we (Frazier and Rayner, 1982) earlier attributed to Minimal Attachment were not due to “garden-path” effects, but rather reflected the extra complexity caused by having to process two sets of clausal relations instead of just one. In the present experiment, we replicated their experiment using eye movement data rather than the subject-paced reading task they used. We found that readers processed Nonminimal Attachment sentences with overt complementizers considerably faster than those without a complementizer. Our results showed that the complexity of Nonminimal Attachment sentences cannot be attributed to their clausal status per se. Differences between the tasks that might contribute to the different pattern of results across the experiments are discussed.
How Simple Complex Words Can Be: Morphological Processing and Word Representations
Authors: Bergman Marijke W. , Hudson Patrick T. W. , Eling Paul A. T. M.
Published: September 2011

In four lexical decision experiments we studied the effect of morphological complexity on word recognition. Some potentially relevant linguistic aspects of derived nouns were varied: the location of the affix (prefix vs. suffix); the genuineness of the affix (real vs. pseudo); the orthographic legality of pseudo-stems; semantic compositionality; the nature of the stem (free vs. bound); the origin of the complex word (Latinate vs. Germanic); the currency of the stem (current vs. moribund). Furthermore, in the first two experiments, we systematically varied the proportion of complex and simple words to see whether strategies influence morphological effects on recognition times. Consistent with Taft's notion of affix stripping, pseudoprefixed words show longer mean decision times and higher error rates than truly prefixed words. Further, the prefixed and nonprefixed (but not pseudoprefixed) words are processed equally rapidly, indicating that a decompositional process is efficient. No differences were found, however, for suffixed, pseudosuffixed, and nonsuffixed words. There was no effect of the proportion of simple and complex words. There are some indications that the etymological origin of words may affect recognition times, but no other linguistic aspects of derivations do so. The results of the four experiments are interpreted as supporting a left-to-right process for word recognition in which morphemes are extracted automatically. During this process information encoded by morphological structure becomes available for other processes.
Selective Attention, Visual Laterality, Awareness, and Perceiving the Meaning of Parafoveally Presented Words
Authors: Lambert Anthony J. , Beard Caroline T. , Thompson Rebecca J.
Published: September 2011

Four experiments are reported investigating the effect of selective attention on the semantic encoding of parafoveally presented words. In Experiments 1 and 2 a right visual field (RVF) performance bias was found when subjects attended to words that could appear either left or right of centre (attend-side condition). When subjects attended centrally and ignored lateral distractor words (attendcentre condition) there was an inhibitory effect of word meaning from left visual field (LVF) distractors. Both inhibitory and facilitatory effects of semantic category were observed from unattended words in Experiments 3 and 4. The pattern of effects depended upon the direction of spatial bias in an attend-side condition. Both kinds of effect occurred even for subjects who were unable to make consciously directed semantic category decisions to words at the same eccentricity (4°) and exposure time (15 msec) as ignored distractors in the attend-centre condition. Implications of these findings for theories of selective attention, for the issue of semantic encoding independent of conscious awareness, and for theories of the relationship between lateral performance biases and functional hemispheric asymmetry are discussed.
The Topology of Performance Curves during 72 Hours of Sleep Loss: A Memory and Search Task
Authors: Babkoff Harvey , Mikulincer Mario , Caspy Tamir , Kempinski Daniel , Sing Helen
Published: September 2011

Three levels of working memory load of a visual search (Memory and Search) task were tested in a 72-hour sleep deprivation paradigm. General performance and accuracy decrease over time with monotonic and rhythmic components. The signal detection discriminability index, d', decreases monotonically with rhythmic variations. The index of response bias, β, shows no monotonic trend, but significant circadian rhythmicity. The extent of the monotonic and rhythmic changes in accuracy and in d’ is directly related to the level of working memory load. The amplitude of the circadian component of accuracy and d’ is enhanced for the higher levels of working memory load. The implication of potentiated circadian rhythmicity as a function of cumulative sleep loss is discussed.
Probabilistic Judgements in Deluded and Non-Deluded Subjects
Authors: Huq S. F. , Garety P. A. , Hemsley D. R.
Published: September 2011

An experiment is described in which deluded subjects were compared with a non-deluded psychiatric control group and a normal control group on a probabilistic inference task. Deluded subjects were found to request less information before reaching a decision and to express higher certainty levels than either control group. They also exhibited over-confidence on estimates of the probability of a future event.

Delusion. A false personal belief based on incorrect inference about external reality and firmly sustained in spite of what almost everyone else believes and in spite of what constitutes incontrovertible and obvious proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person's subculture. [American Psychiatric Association, 1980]
Chronometric Evidence for Central Postponement in Temporally Overlapping Tasks
Authors: Pashler Harold , Johnston James C.
Published: September 2011

When the stimuli from two tasks arrive in rapid succession (the overlapping tasks paradigm), response delays are typically observed. Two general types of models have been proposed to account for these delays. Postponement models suppose that processing stages in the second task are delayed due to a single-channel bottleneck. Capacity-sharing models suppose that processing on both tasks occurs at reduced rates because of sharing of common resources. Postponement models make strong and distinctive predictions for the behaviour of variables slowing particular second-task stages, when assessed in single- and dual-task conditions. In Experiment 1, subjects were required to make manual classification responses to a tone (S1) and a letter (S2), presented at stimulus onset asynchronies of 50, 100, and 400 msec, making R1 responses to S1 as promptly as possible. The second response, R2, but not R1, was delayed in the dual task condition, and the effects of two S2 variables (degradation and repetition) on R2 response times in dual- and single-task conditions closely matched the predictions of a postponement model with a processing bottleneck at the decision/response-selection stage. In Experiment 2, subjects were encouraged to emit both responses close together in time. Use of this response grouping procedure had little effect on the magnitude of R2 response times, or on the pattern of stimulus factor effects on R2, supporting the hypothesis that the same underlying postponement process was operating. R1 response times were, however, dramatically delayed, and were now affected by S2 difficulty variables. The results provide strong support for postponement models of dual-task interference in the overlapping tasks paradigm, even when response times are delayed on both tasks.