Lateral Box Research Articles

Validation of Endogenous Control Genes by Real-Time Quantitative Reverse Transcriptase Polymerase Chain Reaction for Acute Leukemia Gene Expression Studies.

Reference genes are used as internal reaction controls for gene expression analysis, and for this reason, they are considered reliable and must meet several important criteria. In view of the absence of studies regarding the best reference gene for the analysis of acute leukemia patients, a panel of genes commonly used as endogenous controls was selected from the literature for stability analysis: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Abelson murine leukemia viral oncogene human homolog 1 (ABL), Hypoxanthine phosphoribosyl-transferase 1 (HPRT1), Ribosomal protein lateral stalk subunit P0 (RPLP0), β-actin (ACTB) and TATA box binding protein (TBP). The stability of candidate reference genes was analyzed according to three statistical methods of assessment, namely, NormFinder, GeNorm and R software (version 4.0.3). From this study's analysis, it was possible to identify that the endogenous set composed of ACTB, ABL, TBP and RPLP0 demonstrated good performances and stable expressions between the analyzed groups. In addition to that, the GAPDH and HPRT genes could not be classified as good reference genes, considering that they presented a high standard deviation and great variability between groups, indicating low stability. Given these findings, this study suggests the main endogenous gene set for use as a control/reference for the gene expression in peripheral blood and bone marrow samples from patients with acute leukemias is composed of the ACTB, ABL, TBP and RPLP0 genes. Researchers may choose two to three of these housekeeping genes to perform data normalization.

Connection Between Track Geometry Quality and Dynamic Vehicle Response at Various Speeds

Track geometry measurements are widely used for describing track quality. However, derailments and track deterioration are caused by forces arising in vehicle-track system. This research focuses on two types of vehicle response. Firstly, the influence of the longitudinal level irregularities on the vertical wheel-rail forces was examined. Secondly, the correlation between the lateral axle box acceleration and the cross level irregularities was investigated. Track geometry and vehicle response data were acquired simultaneously by a track recording car, formed from a passenger car, at various speeds up to 130 km/h. Vehicle-track forces were calculated based on accelerometers mounted on the car body, bogies and axle boxes, considering mass and moment of inertia. Non-linear regressions resulted in vertical vehicle-track force estimation functions. It was proven that the use of second spatial derivatives of the longitudinal level gave a better estimation than the use of reference TQIs according to European Standard EN 13848-6. A linear relationship was found between the speed and standard deviation of vertical vehicle-track forces. On straight sections with constant speed, correlation coefficients of around 0.8 were found between second spatial derivatives of cross level and lateral axle box acceleration.

PENGARUH LATIHAN LADDER 5HOPS+RUN DAN LATERAL BOX JUMP TERHADAP KELINCAHAN (AGILITY) DAN KECEPATAN (SPEED)

Ladder drill is a jump exercise using a ladder. Box jump is an exercise to jump over a box using one or two legs. Both exercises are two improve agility and speed. The target of this research was male students of class XI MAN 1 Gresik, totaling 101 studens. The type of research used is quantitative with quasi-experimental methods. The design of this study uses the non equivalent control-group before-after design, data analysis uses ANOVA. The data collection process was carried out with a hexagon test and 30 meter sprint. Furthermore, the research data were analyzed using the SPSS application series 22.0. The results showed: (1) there was a4significant effect between the ladder 5hop+run training program on an increase in agility by 3.23% and speed by 3.47%; (2) there is4a significant effect between the lateral box jump training program on an increase in agility of 3.71% and speed of 3.17%; (3) there is4a significant effect between the ladder 5hop+run and the lateral box jump training program on increasing agility by 6.94% and speed by 6.64%.

Avoidance behaviour in laboratory house mice (Musmusculus) and Norway rats (Rattus norvegicus) towards predator odours.

Mus musculus and Rattus sp. are considered pest species because they reach high densities in urban areas, crop fields and food storage and productive systems such as breeding farms and orchards. Their control relies mainly on rodenticide application, but the effectiveness of this application is reduced due to behavioural responses and resistance. Novel methods are based on the use of chemical signals as odours that may be attractants, repellents or may reduce the reproductive success of pest species. The aim of this paper is to study the aversive effect of TMT, cat urine and cat body odour on predator-inexperienced Mus musculus and Rattus norvegicus under laboratory conditions. The experimental apparatus comprised three boxes connected by PVC pipes in a linear arrangement. In lateral boxes, odour sources or distilled water were introduced, while animals were placed in the central box at the beginning of the experiment. Rats showed freezing behaviour, reduced visits in the presence of TMT and cat fur. Mice reduced their visits with cat body and cat urine. This study provides evidence of the usefulness of using fear responses as a way to control rodent pests, which must be adapted to the environment and species to be applied.

Impact of wheel profile evolution on wheel-rail dynamic interaction and surface initiated rolling contact fatigue in turnouts

Hollow wear is a common type of wheel profile evolution in high-speed railway, causing special contact characteristics in turnouts. Taking into account the flexibility of wheelsets and rails in turnout as well as complex constraint conditions, the vehicle-turnout coupling model is built and wheel-rail dynamic interaction in turnouts is analyzed. After calculating the wheel-rail non-Hertz contact behavior with wheel profile evolution, the accumulated surface initiated rolling contact fatigue (RCF) of turnouts are evaluated based on the shakedown theory. Results indicate that the wheel transition position is shifted backwards with wheel profile evolution. The vertical wheel-rail force is contributed by wheelset bending modes in the switch panel, and its maximum value decreases by 22% due to the 87% reduction in vertical contact irregularity in the crossing panel. The severe contact between the false flange and wing rail leads to the aggravation of lateral axle box acceleration (ABA) while the positions of its characteristic frequencies are changed from the point rail to wing rail. When the degree of hollowing becomes medium, wheel profile evolution improves the conformal contact that decreases the accumulated surface initiated RCF in the switch panel. As the degree of hollowing becomes severe, the false flange's contact with the wing rail is prone to RCF in the crossing panel.

Large effect of lateral box size in molecular dynamics simulations of liquid-solid friction.

Molecular dynamics simulations are a powerful tool to characterize liquid-solid friction. A slab configuration with periodic boundary conditions in the lateral dimensions is commonly used, where the measured friction coefficient could be affected by the finite lateral size of the simulation box. Here we show that for a very wetting liquid close to its melting temperature, strong finite size effects can persist up to large box sizes along the flow direction, typically ∼30 particle diameters. We relate the observed decrease of friction in small boxes to changes in the structure of the first adsorbed layer, which becomes less commensurable with the wall structure. Although these effects disappear for lower wetting cases or at higher temperatures, we suggest that the possible effect of the finite lateral box size on the friction coefficient should not be automatically set aside when exploring unknown systems.

Shear-stress relaxation in free-standing polymer films

Using molecular dynamics simulation of a polymer glass model we investigate free-standing polymer films focusing on the in-plane shear modulus $\mu$ and the corresponding shear-stress relaxation modulus $G(t)$ as functions of temperature $T$, film thickness $H$ (tuned by means of the lateral box size $L$) and sampling time $\Delta t$. Various observables are seen to vary linearly with $1/H$ demonstrating thus the (to leading order) linear superposition of bulk and surface properties. In agreement with recent studies on three-dimensional polymer glass-formers, $\mu$ and $G(t)$ are found to decrease continuously with $T$. A jump-singularity is not observed. Confirming the time-translational invariance of our systems, the $\Delta t$-dependence of $\mu$ is traced back to $G(t)$.

Phase diagram of Janus particles: The missing dimension of pressure anisotropy.

Brownian dynamics simulations of single-patch Janus particles under sedimentation equilibrium reveal that the phases found at fixed temperature and volume fraction are extremely sensitive to small changes in lateral box dimension. We trace this sensitivity to an uncontrolled parameter, namely, the pressure component parallel to the hexagonally ordered layers formed through sedimentation. We employ a flexible-cell constant-pressure scheme to achieve explicit control over this usually overlooked parameter, enabling the estimation of phase behavior under given pressure anisotropy. Our results show an increase in the stability range of an orientationally ordered lamellar phase with lateral layer compression and suggest a novel mechanism to control solid-solid phase transitions with negligible change in system volume, thus showing prospect for design of novel structures and switchable crystals from anisotropic building blocks.

SU-G-IeP2-02: A Proposed Solution to Accurate Delineation of External Body Contour Within CT Extended Field of View (eFOV) and the Evaluation of Dosimetric Impact from Image Distortion in EFOV

Purpose: When a patient's anatomy spans beyond the scan field of view (sFOV) in a CT scanner, extrapolation techniques are applied to reconstruct data in the extended field of view (eFOV). However, it's challenging to delineate the external body contour accurately due to image distortions within eFOV. Our proposed solution is to apply TargetTape, a disposable radio-opaque adhesive strip, to patients. Our study investigates the accuracy of geometric reconstruction and the dosimetric impact when using TargetTape in eFOV. Methods: With a GE Optima CT, a cylindrical water phantom was scanned centrally within the sFOV as a reference image. Additional scans were acquired with the phantom extended at 2cm interval from the edge of sFOV to the edge of eFOV. All scans were performed with and without TargetTape. An anthropomorphic pelvic phantom was scanned with a lateral offset to assess the dosimetric impact. Two calculations were performed; one with the automatic external body contour and the other with the manual edits of external body contour based on the visualization of TargetTape. Results: With the aid of TargetTape, the external body contour was accurately delineated within eFOV. The auto-contouring tool in our TPS overestimated the phantom diameter by 0.7cm. For 6MV lateral POP, four-field box, seven-field IMRT and single arc VMAT plans on the pelvic phantom, the dose differences at isocentre were 1.3%, 0.8%, 0.5% and 0.4% respectively. Discrepancy in the DVH was more pronounced for lateral POP and four-field box techniques. Conclusion: The usage of TargetTape on anatomy extending beyond the sFOV provides clear visualization of the body. Although our study reveals small dose difference, our pelvic phantom underestimates the discrepancy. A real patient has image distortion on both sides of the pelvis whereas our phantom only has distortion on one side. Our next study will involve real patient datasets. This study was partially supported by TargetTape.

(Invited) Gate-All-Around Nanowire FETs vs. Triple-Gate FinFETs: On Gate Integrity and Device Characteristics

Triple-gate finFET manufacturing implementation has been successfully enabling continuance of CMOS scaling and Moore’s law [1], but it faces increased scaling challenges for sub-10nm nodes. Gate-all-around (GAA) nanowire (NW) FETs with the thin-body of the device, in a lateral or vertical configuration, fully wrapped around by the gate can be considered the ultimate scaling limit of finFETs [2-4]. They have the potential to offer superior short-channel electrostatics, and are thus regarded as one of the most promising candidates to further support the CMOS roadmap. In this work, we report a comprehensive evaluation of these two different device architectures from a device and circuit perspective, focusing on the key topics of gate stack integrity, leakage, reliability and noise performance and on the impact of the process options used. For simplicity, all devices were built on SOI substrates, with GAA lateral NWFETs obtained via a fins release process at replacement metal gate (RMG) module, which is high density compatible, and wherein diluted-HF was used to remove the BOX under the fins in areas previously covered by the dummy-gates [while the rest of the wafer is covered by the inter-layer dielectric level-zero oxide (ILD0)]. The gate stack used consists of: interfacial layer (IL)-SiO2/HfO2 followed by the effective work function (EWF)-metal (TiN or a TiAl-based stack) and W fill-metal. Examples of TEM images taken across a wire (GAA-NWFET) or a fin (triple-gate finFET) after full processing are shown in Fig.1 [4]. Intrinsic transistor performance (ITP) characteristics show that GAA-NWFETs clearly outperform finFETs when normalizing ION-IOFF per footprint. Furthermore, an evaluation of several doping strategies for both type of devices, using ion implantation (I/I), allowed a comparison of inversion-mode (IM) FETs built with conventional junctions or an extensionless (Extless) scheme [4,5] vs. junctionless (JL) transistors [4,6]. To note that the latter are particularly advantageous in their process simplicity (no junction formation requirements) and compatibility with lower thermal budget flows. Reliability wise, optimized JL and Extless can be very attractive options thanks to a lower oxide field (Eox) at operating conditions. This is indeed confirmed by the GAA-NWFETs in Fig.2. Control of the lateral BOX recess during the fins release process in the GAA flow, and hence of the lateral bottom-gate overlap, is important not only for parasitic reasons but also for reliability purposes. Indeed, TCAD predicts a higher Eox at the bottom-gate edges in case of excessive lateral BOX recess which can lead to degraded BTI behavior for GAA-NWFET vs. finFET. The impact is however considerably less for Extless and JL, increasing the robustness of these devices against process variations in the lateral BOX recess. JL devices were also seen to have improved on and off state hot carrier (HC) reliability behavior as compared to other IM GAA-NWFETs [7]. Interestingly, improved subthreshold slope (SS) values after HC stress were also measured in some JL GAA-NWFETs as a result of the improved electrostatic control and the generation and location of acceptor type of interface traps in the wires of slightly concave sidewalls shape. Low-frequency (LF) noise analysis results suggest to a first order no significant impact of the device architecture on the gate stack integrity in regards to traps/defects. In addition, in agreement with BTI and HC results, JL GAA-NWFETs also show reduced noise. These characteristics, together with the devices smaller IOFF values yielding ring oscillators with substantially lower power dissipation, indicate JL can be an attractive option for low power circuits. Improvements in noise, reliability and mobility performance were also obtained in GAA-NWFETs by introduction of a TiAl-based EWF-metal [4,8], in line with the results previously reported in [9] on finFETs using Al diffusion mechanisms for EWF modulation.

The Teatro Cervantes in Alcalá: CHAPTER 3 The 1990s:Recovery and Restoration

The Teatro Cervantes in Alcalá CHAPTER 3 The 1990s:Recovery and Restoration John J. Allen The author writes: “In the first part of this series on the Teatro Cervantes in Alcalá I expressed my intention to follow it with a series of pieces on that playhouse as well as to publish the material separately in book form in Spanish. Delays in publication of the second piece in the series prompted me to prioritize the Spanish version of the material, which has now appeared in Barcelona, published by TC/12 in Barcelona, with the title La piedra de Rosetta del teatro comercial en Europa. To facilitate accessibility of the material to Elizabethan scholars who do not know Spanish, the editors of Bulletin of the Comediantes have encouraged me to continue the English version here, where I began it. What follows is Chapter 3.” Juan Sanz Ballesteros, Miguel Ángel Coso Marín, and Mercedes Higuera Sánchez-Pardo had saved the Teatro Cervantes from destruction and blocked implementation of ill-informed and hasty operations that would have obscured the evidence of its successive transformations. The city had sought authoritative guidance for its reconstruction and the advisory commission had fully endorsed the insistence of the three young researchers that the work “not destroy the remains of any of the three main historical phases through which it has passed.” “The policy,” the commission report said, “must not be to restore one specific phase in the evolution of this building but rather to reveal the evidence it offers of this continuous history of theatrical life.” The work of recovery and restoration could now begin. The first step in moving ahead was to get as clear an idea as possible of the physical arrangements in the initial corral stage of the playhouse. In his history of the Teatro Cervantes, José Antonio Rayón had provided a thorough account of the conversion of the rectangular coliseum into the Romantic ellipse, but what was known of the initial conversion from corral to coliseum? Rayón must have seen the coliseum structure as a single, independent building since, as we have seen, he never fully grasped the nature of the lateral box evolution. This is [End Page 197] actually quite puzzling, given that he understood the initial corral conformation of his theater perfectly. As he says, the Teatro Cervantes, “designed on the plan of the Corral de la Cruz in Madrid and similar to it, consisted only of stands at each side of the covered stage, and facing it, windows and boxes” (“habiéndose formado a la traza y semejanza del Patio de la Cruz de Madrid, no constaba más que de andamios a los lados del teatro cubierto y, a su frente, ventanas y aposentos”).1 This statement makes it clear that he was not misled, as were later investigators, by the collapsed chronology of this process in the Madrid corrales given by Casiano Pellicer. And as we have seen, he knew that rooms on alien property in the inn next door to his own playhouse on the right had been converted to lateral boxes in 1602, when the entrance to the women’s cazuela was opened there. He also knew of a royal decree, to which he alluded in his account, that had prohibited linking theaters like his with neighboring buildings, and consequently he knew that some of his own patrons who had previously accessed their boxes directly from the inn next door were by then no longer allowed to do so. Since he himself transformed the coliseum into the Romantic ellipse, Rayón obviously also knew exactly what the rectangular coliseum looked like. Given that knowledge of the whole sequence of events prior to 1830, how is it possible that he saw the coliseum structure as a single independent building, dismissing the deal made for the boxes on the north side as an anomaly? It is difficult to imagine that the elements could have come together into what seemed like a single structure before 1746, when the whole property first came under single ownership. And it seems clear that the latest it could have been accomplished was 1769, when the entire set of structures was...

Fundamental Mode Estimation for Modern Cable-Stayed Bridges Considering the Tower Flexibility

The design of cable-stayed bridges is typically governed by the dynamic response. This work provides designers with essential information about the fundamental vibration modes, proposing analytical expressions based on the mechanical and geometrical properties of the structure. Different bridge geometries are usually considered in the early design stages until the optimum solution is defined. In these design stages, the analytical formulation is advantageous, because finite-element models are not required and modifying the bridge characteristics is straightforward. The influence of the tower flexibility is included in this study, unlike in previous attempts on mode estimation. The dimensions and proportions of the canonical models proposed in the analytical study stem from the previous compilation of the dimensions of a large number of constructed cable-stayed bridges. Five tower shapes, central or lateral cable-system layouts and box- or U-shaped deck sections, have been considered. The vibration properties of more than 1,000 cable-stayed bridges with main spans ranging from 200 to 800 m long were extracted within an extensive parametric analysis. The Vaschy-Buckingham theorem of dimensional analysis was applied to the numerical results to propose the formulation for period estimation. Finally, the formulas were validated with the vibration properties of 17 real cable-stayed bridges constructed in different countries. The importance of the tower flexibility is verified, and the errors observed are typically below 15%, significantly improving the estimations obtained by previous research works.

Can carotid-sparing radiotherapy approaches replace with conventional techniques for the patients with T1 glottic laryngeal cancer?

This study aims to compare the carotid artery doses applied with various radiotherapy techniques for the treatment of T1N0 glottic larynx cancer. Five patients were simulated with using computed tomography (CT). Clinical (CTV) and planning target volumes (PTV) were created for T1N0 glottic larynx cancer. Planning risk volumes (PRV) were constructed for carotid arteries and spinal cord. Three irradiation planning, opposed lateral box field (OLBF), three dimension conformal radiation therapy (3DCRT), intensity modulated radiation therapy (IMRT) were done for each patient. Over 95% of planned target volumes were loaded with predetermined dose (a total of 62.25 Gy of 2.25 Gy daily dose). The comparison of the treatment planning of five T1 glottic larynx cancer, three involving the right vocal cord and two involving the left vocal cord, the technique of IMRT planning was provided the best carotid-sparing doses. Mean carotid V35, V50, and V63 values including OLBF, 3DCRT, and IMRT were 70%, 47%, 35%; 55%, 15%, 5% and 28%, 6%, 0%, respectively. The statistical comparison of V35, V50 and V63 revealed significant values for OLBF and IMRT. Dose of spinal cord did not exceed 45 Gy for any of radiation treatment planning. Between the three techniques, there was no significant difference in terms of conformity index and dose distribution was homogenous with all techniques. It is obvious that IMRT planning technique can decrease the carotid artery radiation doses in early stage glottic larynx cancer.

3 Different Types of Strength Training in Older Women

The objective of the present study was to evaluate and compare the neuromuscular, morphological and functional adaptations of older women subjected to 3 different types of strength training. 58, healthy women (67 ± 5 year) were randomized to experimental (EG, n=41) and control groups (CG, n=17) during the first 6 weeks when the EG group performed traditional resistance exercise for the lower extremity. Afterwards, EG was divided into three specific strength training groups; a traditional group (TG, n=14), a power group (PG, n=13) that performed the concentric phase of contraction at high speed and a rapid strength group (RG, n=14) that performed a lateral box jump exercise emphasizing the stretch-shortening-cycle (SSC). Subjects trained 2 days per week through the entire 12 weeks. Following 6 weeks of generalized strength training, significant improvements occurred in EG for knee extension one-repetition (1RM) maximum strength (+19%), knee extensor muscle thickness (MT, +15%), maximal muscle activation (+44% average) and onset latency ( -31% average) for vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) compared to CG (p<0.05). Following 6 more weeks of specific strength training, the 1RM increased significantly and similarly between groups (average of +21%), as did muscle thickness of the VL (+25%), and activation of VL (+44%) and VM (+26%). The onset latency of RF (TG=285 ± 109 ms, PG=252 ± 76 ms, RG=203 ± 43 ms), reaction time (TG=366 ± 99 ms, PG=274 ± 76 ms, RG=201 ± 41 ms), 30-s chair stand (TG=18 ± 3, PG=18 ± 1, RG=21 ± 2) and counter movement jump (TG=8 ± 2 cm, PG=10 ± 3 cm, RG=13 ± 2 cm) was significantly improved only in RG (p<0.05). At the end of training, the rate of force development (RFD) over 150 ms (TG=2.3 ± 9.8 N·s(-1), PG=3.3 ± 3.2 N·s(-1), RG=3.8 ± 6.8 N·s(-1), CG=2.3 ± 7.0 N·s(-1)) was significantly greater in RG and PG than in TG and CG (p<0.05). In conclusion, rapid strength training is more effective for the development of rapid force production of muscle than other specific types of strength training and by consequence, better develops the functional capabilities of older women.

Direct Fourier Analysis of Lipid Bilayer Fluctuations in Particle-Based Simulations

The particles in the lipid bilayer undergo fluctuations from their equilibrium positions. These motions are best described in terms of correlated monolayer motions (undulations), anticorrelated monolayer motions (thickness fluctuations) and number density correlations, both within and between the monolayers. Particle-based computer simulations, atomistic or coarse-grained, can be used to calculate the spectra of these equilibrium fluctuations. This has conventionally been done by interpolating the particle structure onto a grid to facilitate for the discrete Fourier transform. However, the gridding introduces artifacts and an upper cutoff on the available wave vectors. Here, we instead analyze the simulations directly in Fourier space, circumventing the need for a grid approximation. The fluctuation spectra can then be calculated at high precision up to any wave vector desired, and the low wave vectors are only bounded by the size of the lateral simulation box. From the analysis, a picture emerges which bridges a continuum regime at low wave vectors, and a domain that can be attributed to the in-plane bilayer molecular structure at high wave vectors. We calculate spectra for undulations, thickness fluctuations, and the spectrum of the number density along the undulating surface, and we discuss how the shape of the spectra in the low-wave vector and high-wave vector regimes are related to membrane material constants, and give some predictions from an analytical theory based on equilibrium correlation functions.

The effect of load weight on balance control during lateral box transfers

Few studies have endeavoured to measure balance control during manual material handling. This study examined the effects of load weight during a stationary manual material handling task. In total, 36 healthy participants completed 180° lateral transfer tasks of a loaded (5% of body weight) and an unloaded box. The projection of the centre of mass onto the base of support, as measured via a passive-marker 3-D motion analysis system, was used to quantify balance control. Muscle activities of lower extremity muscles were also measured. When moving the loaded box, individuals ventured ≥ 1 cm closer to the edges of the base of support and increased centre of mass movement up to 14%. In addition, muscle electromyographic activity on both sides of the shank increased. In summary, during loaded configurations, vulnerability to loss of balance was increased and individuals appeared to adapt by increasing co-contraction of the shank muscles suggesting increased ankle stiffness. Statement of Relevance: Industries requiring manual material handling have a particularly high rate of injuries due to falls. This study suggests that larger load weights during lateral material handling tasks adversely affect balance control and may create a vulnerability to imbalance throughout the entire manoeuvre.

Left visual neglect: is the disengage deficit space- or object-based?

Attention can be directed to spatial locations or to objects in space. Patients with left unilateral spatial neglect are slow to respond to a left-sided target when it is preceded by a right-sided "invalid" cue, particularly at short cue-target intervals, suggesting an impairment in disengaging attention from the right side in order to orient it leftward. We wondered whether this deficit is purely spatial, or it is influenced by the presence of a right-sided visual object. To answer this question, we tested 10 right brain-damaged patients with chronic left-neglect and 41 control participants on a cued response time (RT) detection task in which targets could appear in either of two lateral boxes. In different conditions, non-informative peripheral cues either consisted in the brightening of the contour of one lateral box (onset cue condition), or in the complete disappearance of one lateral box (offset cue condition). The target followed the cue at different stimulus-onset asynchronies (SOAs). If the disengagement deficit (DD) is purely space-based, then it should not vary across the two cueing conditions. With onset cues, patients showed a typical DD at short SOAs. With offset cues, however, the DD disappeared. Thus, patients did not show any DD when there was no object from which attention must be disengaged. These findings indicate that the attentional bias in left-neglect does not concern spatial locations per se, but visual objects in space.

A Numerical Modeling of Rayleigh–Marangoni Steady Convection in a Non-Uniform Differentially Heated 3D Cavity

A numerical study of a buoyancy driven convection flow in presence of thermocapillarity has been developed. The fluid is a silicone oil (Prandtl number equal to 105) contained in a three-dimensional box bounded by rigid and impermeable walls with top free surface exposed to a gaseous phase. At the lateral box walls a different non-uniform temperature distribution is assumed so to induce horizontal convection and to keep separated thermocapillary and buoyancy effects. The vorticity-velocity formulation of the time-dependent Navier–Stokes equations for a non-isothermal incompressible fluid is used. A procedure based on a linearized fully implicit finite difference second order scheme has been adopted. We obtained very complex steady configurations for several values of the temperature difference at the lateral walls, ΔTe30, 40 and 50°C. Along the direction perpendicular to the lateral walls, for ΔT increasing, we observe a physically meaningful growth of heat transfer. Confidence in these results is supported by a comparison with recent experimental and numerical observations.

Dynamics of retreating slabs: 2. Insights from three‐dimensional laboratory experiments

A laboratory analogue of a three‐layer linear viscous slab‐upper mantle‐lower mantle system is established in a silicone putty, honey and crystallized honey tank experiment. The same setup as in the numerical investigation (part 1) is used. We focus on the interaction of the slab with the induced passive mantle flow by widely varying the mantle volume flux boundary conditions. In our numerical experiments the lateral volume flux was set to zero. In interpreting the results relative to the real Earth, the base of the box is taken as the bottom of the mantle convection system, while the lateral boundaries may be associated with the presence of other nearby slabs. Dynamic force equilibrium, assessed on the basis of an analytical review of forces, is described for four different phases: (1) the subduction initiation instability, (2) the accelerating dynamic free fall phase of the slab, (3) the dynamic interaction with the 660‐km discontinuity, and (4) a final phase of steady state trench retreat. Phase 3 is an important feature not observed in the numerical experiments. This highly dynamic phase of interrupted trench retreat can therefore be attributed to boundary conditions on mantle volume flux. On the basis of integration constants of force equilibrium in phases 2 and 4 we identify two different classes of volume flux: one in which the lateral boundary can be considered open and the other class where it is “closed.” Closed boundary condition cases are obtained if any of the lateral box boundaries are 600 km away from the slab. Assuming a one‐to‐one relation between trench retreat and back arc spreading, enigmatic observations of episodic opening of back arc basins can be explained by our experimental observations.

Modulating the attentional bias in unilateral neglect: the effects of the strategic set.

Left unilateral neglect is a neurological condition characterized by an impairment in orienting and responding to events occurring on the left side. To gain insight into the brain mechanisms of space processing and to provide theoretical foundations for patient rehabilitation, it is important to explore the attentional bias shown by neglect patients in the light of existing models of normal attentional orienting. Three experiments tested the hypothesis that attentional bias in neglect involves primarily exogenous, or stimulus-based, orienting of attention, with relatively preserved endogenous, or voluntary, orienting. Six patients with right hemisphere damage and left unilateral neglect and 18 age-matched participants without brain damage performed a cued reaction time (RT) task to targets which could appear in one of two lateral boxes. Cues consisted of a brief brightening of the contour of one of the boxes. The target followed the cue at 150, 550, or 1000 ms stimulus-onset asynchrony (SOA). In experiment 1, the cues were not informative about the future location of the target, and thus elicited a purely exogenous orienting of attention. Controls showed slowed RTs to the cued locations at SOAs > 150 ms, consistent with the notion of inhibition of return (IOR). Neglect patients had no evidence of IOR for right targets; they showed a disproportionate cost for left targets preceded by right (invalid) cues; this cost was maximal at the shortest SOA, consistent with the idea of a biased exogenous orienting in neglect. In experiment 2, 80% of the cues were valid (i.e., they correctly predicted the location of the impending target), thus inducing an initially exogenous, and later endogenous, attentional shift toward the cued box. Neglect patients showed again a cost for left invalidly cued targets, which this time persisted at SOAs > 150 ms, as if patients' attention had been cued to the right side not only exogenously, but also endogenously, thus rendering more difficult an endogenous reorienting toward the left. In experiment 3, only 20% of the cues were valid, so that the best response strategy was to endogenously orient attention toward the box opposite to the cued one. Controls were able to take advantage of invalid cues to rapidly respond to targets. In this condition, neglect patients were able to nullify their spatial bias; they achieved their fastest RTs to left targets, which were in the range of their RTs to right targets. However, for neglect patients fast responses to left targets occurred only at 1000 ms SOA, while controls were able to redirect their attention to the uncued box already at 550 ms SOA. Altogether, these results suggest that endogenous orienting is relatively spared, if slowed, in unilateral neglect.