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This article examines the applicability of prognostic scores for decision-making in patients with critical left ventricular outflow tract (LVOT) obstruction and borderline left ventricle (LV) who undergo the Ross-Konno procedure. The study evaluated four scores (Rhodes, Discriminant, CHSS1, and CHSS2) in a cohort of 51 patients treated at a single center. The results showed significant differences between patients who underwent biventricular repair and those who underwent univentricular repair. The study concludes that the validity of these scores is limited in Ross-Konno patients, and using the proposed changes after the procedure may result in an overemphasis on biventricular repair and a loss of specificity. [Extracted from the article]

Results from centrifuge modelling of tunnelling beneath loaded non-displacement piles in clay are presented in this paper; the principal variables were soil strength, pile loading and pile position relative to the tunnel. The details of the experimental set-up and the importance of understanding the loading history of the soil and the piles are presented in a companion paper. The subsurface pile-soil interaction was captured through particle image velocimetry; the effects of pile loading and pile position were found to have a significant impact on pile settlements. Analysis of tunnel-pile interaction through t- z load-transfer modelling of the pile-soil interface is presented using the approach described in the companion paper. The mechanisms observed in the centrifuge tests are predicted reasonably well. A significant improvement in the prediction of the induced pile loading and settlements was achieved with the inclusion of plasticity and simple power-law non-linearity for the soil. [ABSTRACT FROM AUTHOR]

This article discusses the long-term outcomes of the extracardiac Fontan procedure, which is typically performed in patients aged 2-5 years with univentricular heart conditions. However, in some cases, the procedure is delayed until adolescence or adulthood. The study examines eight patients who underwent the procedure at the age of 16 or older. The results show that the extracardiac Fontan procedure can effectively improve the quality of life in these patients. The study also highlights the safety of the procedure and the impressive improvement in the patients' overall well-being. [Extracted from the article]

New developments in both the theory and the practice of tunnelling are covered in the lecture. The important relationship between tunnelling and geotechnics is highlighted, and recent advances in research and practice are described, drawing on model studies, theoretical developments and field measurements from case histories from around the world. Simplified plasticity models are presented that can be used by designers to assess ground movements and tunnel lining loads in complex ground conditions. The important role of pilot tunnels and in situ measurements to validate such models, drawing on a case history from Bolu, Turkey, and on other tunnelling projects, is described. Recent technical advances in earth pressure balance tunnelling are considered, illustrated by measurements from the Channel Tunnel Rail Link project, with emphasis on key factors influencing volume loss, such as face pressure, soil conditioning and effective screw conveyor operation. A recent case history in Bologna is described, in which the innovative use of directional drilling to install curved grout tubes was employed for a compensation grouting project in granular soils. Timedependent ground movements and tunnel lining distortions occurring after tunnelling are discussed, their magnitude depending on the relative permeability of the tunnel lining and soil, the degree of anisotropy of the soil permeability, and the initial pore pressure prior to tunnelling. The effects of tunnelling-induced settlements on pipelines are considered, drawing on centrifuge tests and analytical solutions, and a new design approach is presented, taking into account the reduction of soil stiffness with increasing shear strain as a result of tunnel volume loss. The lecture concludes with a description of a distributed strain sensing technique using fibre optic technology, based on Brillouin optical time domain reflectometry (BOTDR), and its innovative application to field monitoring of a masonry tunnel subjected to new tunnel construction beneath it. [ABSTRACT FROM AUTHOR]

A new theoretical model describing the total pressure gradient and torque in a tunnelling machine screw conveyor is proposed. The theory develops new equations relating the pressure gradient and torque to the screw geometry, the shear stresses acting in the screw conveyor, and the material flow. The equations are expressed in dimensionless form, allowing application to screw conveyors of different scales. The theory is validated against measurements from laboratory model screw conveyor tests with clay soils with varying properties and operating conditions. The theory successfully describes key features of the observed mechanics of the model conveyor operation, and accurately predicts the test measurements. The proposed theory provides insight into the fundamental mechanics of screw conveyor operations, and can be used in the design of tunnelling machine screw conveyors. The theory can also be applied to other forms of screw conveyors and extruders operating with plastic materials. [ABSTRACT FROM AUTHOR]

Aim: To assess potential function of each two-component signal transduction system in the expression of Streptococcus mutans virulence properties. Methods and Results: For each two-component system (TCS), the histidine kinase-encoding gene was inactivated by a polymerase chain reaction (PCR)-based deletion strategy and the effects of gene disruption on the cell’s ability to form biofilms, become competent, and tolerate acid, osmotic, and oxidative stress conditions were tested. Our results demonstrated that none of the mutations were lethal for S. mutans. The TCS-2 (CiaRH) is involved in biofilm formation and tolerance to environmental stresses, the TCS-3 (ScnRK-like) participates in the survival of cells at acidic pH, and the TCS-9 affects the acid tolerance response and the process of streptococcal competence development. Conclusions: Our results confirmed the physiological role of the TCS in S. mutans cellular function, in particular the SncRK-like TCS and TCS-9 as they may represent new regulatory systems than can be involved in S. mutans pathogenesis. Significance and Impact of the Study: Multiple TCS govern important biological parameters of S. mutans enabling its survival and persistence in the biofilm community. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effects of soil loading on large-diameter, close-fitting, nonbonded, flexible sewer liners as typified by ‘cured-in-place pipes’ (CIPP). CIPP is the process whereby a polymeric pipe lining is cast directly against the wall of a deteriorating sewer pipe. The transfer of soil loading to CIPP liners is strongly influenced by the interaction between the existing host pipe and the surrounding soil. In adjusting to deterioration events of the host pipe and possible void formation in the soil, the existing pipe-soil structure deforms and interacts with the liner inside it. By monitoring deformations of the liner and host structure the magnitude of load transfer can be inferred. The paper describes 1/30th scale physical models tested in dry sand under 30g of centrifugal acceleration. The models included: (a) a host pipe with two simulated modes of deterioration; (b) an instrumented close-fitting, nonbonded, flexible liner; (c) voids in the soil; and (d) moving, heavy traffic loading. The tests showed that, even under extreme loading conditions, the deformations of the liner are relatively small (2-3% of diameter), implying that the presence of a thin, flexible non-bonded and close-fitting liner has an important stiffening effect on the response of the deteriorating host pipe. The important influence of void position in the surrounding soil was also demonstrated. [ABSTRACT FROM AUTHOR]

A modification to the load factor approach to estimating undrained volume loss for open-face tunnelling in London Clay is proposed. The modified approach is based on the nature of ground movement observed during construction of the Jubilee Line Extension at St James's Park and Elizabeth House for different stages of open-face shield tunnel construction and tunnelling using sprayed concrete linings, described in a companion paper. The new approach is shown to provide good estimates of the volume loss observed for open-face shield tunnelling in London Clay at Green Park and Regents Park. [ABSTRACT FROM AUTHOR]

This paper describes the nature of ground movement observed during construction of the Jubilee Line Extension at St James's Park and beneath Elizabeth House for different stages of tunnelling in London Clay, using open-face shield construction and sprayed concrete linings respectively. Volume loss is defined as the volume of ground loss as a proportion of the final tunnel volume and is measured in the plane of the tunnel. Volume losses corresponding to different phases of tunnelling at St James's Park and beneath Elizabeth House are identified in the paper. A companion paper presents a new approach to estimating volume losses for each phase of open-face tunnelling in London Clay. [ABSTRACT FROM AUTHOR]

ÀA kinematic plastic solution has been developed for ground movements around a shallow, unlined tunnel embedded within an undrained clay layer. In this solution, the pattern of deformation around the tunnel is idealised by a simple plastic deformation mechanism. Within the boundaries of the deformation mechanism, the soil is required to shear compatibly and continuously with no relative sliding at the boundaries. The soil is regarded here as a rigid plastic (Tresca) material. The plausibility of the proposed mechanism is demonstrated by comparison with limit analysis calculations and centrifuge test results. [ABSTRACT FROM AUTHOR]

Control of the excavation process of an earth pressure balance (EPB) tunnelling machine depends on control of the soil flow through the screw conveyor. An instrumented 1 : 10 scale model screw conveyor was designed and commissioned, and tests were performed with consolidated kaolin and compacted London Clay and Lambeth Group samples pre-conditioned with soil conditioning agents commonly used in EPB tunnelling machines. During steady-state operation, the measured shear stress acting on the conveyor casing was found to be constant along the conveyor, leading to a linear total pressure gradient. The casing shear stress was approximately equal to the undrained shear strength of the soil, and the screw torque increased linearly with the casing shear stress. Effects of varying sample strengths, screw speeds, screw geometry and the discharge outlet restriction on the total pressure gradient, casing shear stress, and screw torque are illustrated by the test results. The tests provide new insight into the behaviour of soil flow through screw conveyors. [ABSTRACT FROM AUTHOR]

This paper reports the findings of a field study of the ground conditions around an old tunnel in London Clay at a greenfield site in Kennington, South London. Ground conditions were identified from a borehole investigation incorporating a programme of in situ pore water pressure monitoring, geotechnical testing and sampling. Additionally, laboratory classification of the samples and a suite of high-quality triaxial tests were carried out. The results of this investigation are presented and discussed in conjunction with published London Clay data. The presence of a tunnel beneath the site allowed the investigation of its influence on the local soil and groundwater conditions. [ABSTRACT FROM AUTHOR]

We report initial NMR studies of continuous flow laser-polarized xenon gas, both in unrestricted tubing, and in a model porous media. The study uses Pulsed Gradient Spin Echo-based techniques in the gas-phase, with the aim of obtaining more sophisticated information than just translational self-diffusion coefficients. Pulsed Gradient Echo studies of continuous flow laser-polarized xenon gas in unrestricted tubing indicate clear diffraction minima resulting from a wide distribution of velocities in the flow field. The maximum velocity experienced in the flow can be calculated from this minimum, and is seen to agree with the information from the complete velocity spectrum, or motion propagator, as well as previously published images. The susceptibility of gas flows to parameters such as gas mixture content, and hence viscosity, are observed in experiments aimed at identifying clear structural features from echo attenuation plots of gas flow in porous media. Gas-phase NMR scattering, or position correlation flow-diffraction, previously clearly seen in the echo attenuation data from laser-polarized xenon flowing through a 2 mm glass bead pack is not so clear in experiments using a different gas mixture. A propagator analysis shows most gas in the sample remains close to static, while a small portion moves through a presumably near-unimpeded path at high velocities. [Copyright &y& Elsevier]

We report a systematic study of xenon gas diffusion NMR in simple model porous media, random packs of mono-sized glass beads, and focus on three specific areas peculiar to gas-phase diffusion. These topics are: (i) diffusion of spins on the order of the pore dimensions during the application of the diffusion encoding gradient pulses in a PGSE experiment (breakdown of the narrow pulse approximation and imperfect background gradient cancellation), (ii) the ability to derive long length scale structural information, and (iii) effects of finite sample size. We find that the time-dependent diffusion coefficient, D(t), of the imbibed xenon gas at short diffusion times in small beads is significantly affected by the gas pressure. In particular, as expected, we find smaller deviations between measured D(t) and theoretical predictions as the gas pressure is increased, resulting from reduced diffusion during the application of the gradient pulse. The deviations are then completely removed when water D(t) is observed in the same samples. The use of gas also allows us to probe D(t) over a wide range of length scales and observe the long time asymptotic limit which is proportional to the inverse tortuosity of the sample, as well as the diffusion distance where this limit takes effect (∼1–1.5 bead diameters). The Pade´ approximation can be used as a reference for expected xenon D(t) data between the short and the long time limits, allowing us to explore deviations from the expected behavior at intermediate times as a result of finite sample size effects. Finally, the application of the Pade´ interpolation between the long and the short time asymptotic limits yields a fitted length scale (the Pade´length), which is found to be ∼0.13b for all bead packs, where b is the bead diameter. [Copyright &y& Elsevier]

Time-resolved photoluminescence spectroscopy has been used to investigate carrier decay dynamics in a In[sub x]Ga[sub 1-x]As[sub 1-y]N[sub y] (x∼0.03, y∼0.01) epilayer grown on GaAs by metal organic chemical vapor deposition. Time-resolved photoluminescence (PL) measurements, performed for various excitation intensities and sample temperatures, indicate that the broad PL emission at low temperature is dominated by localized exciton recombination. Lifetimes in the range of 0.07-0.34 ns are measured; these photoluminescence lifetimes are significantly shorter than corresponding values obtained for GaAs. In particular, we observe an emission energy dependence of the decay lifetime at 10 K, whereby the lifetime decreases with increasing emission energy across the PL spectrum. This behavior is characteristic of a distribution of localized states, which arises from alloy fluctuations. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the polarization of photoemitted electrons from thin Al[subx]Ga[sub1-x]As layers grown by molecular-beam epitaxy as a function of aluminum concentration by varying x in steps of 0.05 from 0 to 0.15. Advantages of photoemission from negative-electron-affinity; Problems in polarized photoemission from gallium arsenide; Ways to achieve a wavelength shift.

The article profiles the 46th Lecture of the British Geotechnical Society speaker Robert J. Mair. It provides a comprehensive discussion on Mair's professional achievements and expertise. It notes his involvement in several tunneling projects which include the Jubilee Line Extension Project, Channel Tunnel Rail Link, and the Waterloo escalator tunnel in London, England. It further states Mair's sense of organization, diplomatic skills and geotechnical expertise.

This article examines the long-term outcomes of pacemaker therapy in extracardiac Fontan patients, who undergo a specific type of heart surgery. The study found that a small percentage of Fontan patients required a pacemaker, and these patients had a lower survival rate compared to those without a pacemaker. The primary causes of heart transplantation or death in patients with pacemakers were ventricular failure and complications related to the Fontan procedure. The study suggests that extracardiac Fontan patients should be closely monitored for long-term complications. [Extracted from the article]

This article discusses the potential use of the lipophilic statin atorvastatin to prevent endocardial fibroelastosis (EFE) in congenital heart defects. EFE is regulated through the TGF-ß pathway via endothelial-to-mesenchymal transition (EndMT) in the endocardium. The study found that atorvastatin treatment reduced EndMT and increased the expression of the zing finger protein Krüppel-like factor 2 (KLF2), which protects the vascular endothelium. In an animal model, atorvastatin treatment resulted in a decrease in EFE thickness and myocardial infiltration. These findings suggest that upregulation of KLF2 with atorvastatin could be a potential treatment approach for patients with EFE. [Extracted from the article]

A research programme conducted at the University of Cambridge geotechnical centrifuge provided high-quality data on the interaction effects of open-faced tunnelling beneath non-displacement piles in clay. This paper presents details of the novel centrifuge package, including the reinforced composite piles used to measure loads during the centrifuge tests. Attention is particularly drawn to the importance of temperature compensation and the corresponding effect on the model piles. Results from maintained pile load tests conducted in the centrifuge are presented; through photogrammetric techniques, these are compared with data from pile load cells. The results, also compared with analytical t- z power-law modelling of the soil stress-strain behaviour based on triaxial tests, illustrate the importance of modelling the full history of both soil and piles prior to any subsequent tunnelling-induced loading. The experimental results of the simulated tunnelling tests on piles are presented and compared with simple analytical solutions in a companion paper. [ABSTRACT FROM AUTHOR]

Time-resolved photoluminescence (PL) spectroscopy was used to investigate carrier distributions in a GaN/AlGaN multiple quantum well (MQW) sample under high excitation intensities necessary to achieve lasing threshold. Room temperature PL spectra showed optical transitions involving both confined and unconfined states in the quantum well structure. Analysis of the experimental results using a microscopic theory, indicates that at high excitation the carrier distributions are characterized by plasma temperatures which are significantly higher than the lattice temperature. The implications of our findings on GaN MQW laser design are also discussed. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Optical resonance modes have been observed in optically pumped microdisk cavities fabricated from 50 Å/50 Å GaN/Al[sub x]Ga[sub 1-x]N(x∼0.07) and 45 Å/45 Å In[sub x]Ga[sub 1-x]N/GaN(x∼0.15) multiple quantum well structures. Microdisks, approximately 9 μm in diameter and regularly spaced every 50 μm, were formed by an ion beam etch process. Individual disks were pumped at 300 and 10 K with 290 nm laser pulses focused to a spot size much smaller than the disk diameter. Optical modes corresponding to (i) the radial mode type with a spacing of 49–51 meV (both TE and TM) and (ii) the Whispering Gallery mode with a spacing of 15–16 meV were observed in the GaN microdisk cavities. The spacings of these modes are consistent with those expected for modes within a resonant cavity of cylindrical symmetry, refractive index, and dimensions of the microdisks under investigation. The GaN-based microdisk cavity is compared with its GaAs counterpart and implications regarding future GaN-based microdisk lasers are discussed. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The paper examines the problem of tunneling beneath buried pipelines and the relationship between soil strains and pipeline bending behavior. Data are presented from centrifuge tests in which tunnel volume loss was induced in sand beneath pipelines of varying stiffness properties. The model tunnel and pipelines were all placed at a Perspex wall of the centrifuge strong box such that image-based deformation analyses could be performed. The method provided detailed data of subsurface soil and pipe displacements and illustrated the soil-pipe interaction mechanisms that occurred during tunnel volume loss, including the formation of a gap beneath the pipes. The relationship between tunnel volume loss, soil strain, and pipe bending behavior is illustrated. Experimental results of pipe bending moments are compared against predictions: (1) assuming the pipe simply follows greenfield displacements; (2) using an elastic continuum solution; and (3) using a new method in which an 'out-of-plane' shear argument, due to soil-pipe interaction, is introduced into the elastic continuum solution. It is shown that the new method gives the best prediction of experimental pipe bending moments. [ABSTRACT FROM AUTHOR]

Diaphragm walls are used to support the sides of deep excavations, and they are often installed close to existing buildings. Construction of these cast-in-place permanent retaining structures can result in substantial soil deformations and potential damage to adjacent structures. A better understanding of this soil-structure interaction problem would greatly benefit safe and economic design. There is particular uncertainty about the interaction and response of piled foundations to diaphragm wall construction, particularly where there could be trench instability at depth. A series of small-scale model tests has been conducted using the 8 m diameter geotechnical centrifuge at Cambridge University to study the installation effects of diaphragm walls on a single adjacent pile in dense fine sand. An instrumented model pile was installed and loaded at various offsets from a slurry-filled model trench. Two trench lengths were investigated. The tests have provided a detailed insight into the movements of the pile and the progressive redistribution of loads along the pile. A generalised mechanism for the pile- trench interaction is also proposed. The main factors affecting the severity of pile response are slurry level (trench pressure), pile offset distance (α) and trench length (L). The experiments showed that the risk of system instability reduced significantly with x/L values above 1.15. [ABSTRACT FROM AUTHOR]

Following a tunnel excavation in low-permeability soil, it is commonly observed that the ground surface continues to settle and ground loading on the tunnel lining changes, as the pore pressures in the ground approach a new equilibrium condition. The monitored ground response following the tunnelling under St James's Park, London, shows that the mechanism of subsurface deformation is composed of three different zones: swelling, consolidation and rigid body movement. The swelling took place in a confined zone above the tunnel crown, extending vertically to approximately 5 m above it. On the sides of the tunnel, the consolidation of the soil occurred in the zone primarily within the tunnel horizon, from the shoulder to just beneath the invert, and extending laterally to a large offset from the tunnel centreline. Above these swelling and consolidation zones the soil moved downward as a rigid body. In this study, soil-fluid coupled three-dimensional finite element analyses were performed to simulate the mechanism of long-term ground response monitored at St James's Park. An advanced critical state soil model, which can simulate the behaviour of London Clay in both drained and undrained conditions, was adopted for the analyses. The analysis results are discussed and compared with the field monitoring data. It is found that the observed mechanism of long-term subsurface ground and tunnel lining response at St James's Park can be simulated accurately only when stiffness anisotropy, the variation of permeability between different units within the London Clay and non-uniform drainage conditions for the tunnel lining are considered. This has important implications for future prediction of the long-term behaviour of tunnels in clays. [ABSTRACT FROM AUTHOR]

A new analytical method is introduced for calculating displacements due to tunnelling. This is conceived within the framework of the bound theorems of plasticity, but allowing for soil strain-hardening. The ground displacements due to tunnelling are idealised by a simple displacement mechanism of distributed shearing in the plane of the tunnel cross-section. The tunnel support pressure corresponding to a certain volume loss is calculated from energy balances of the work dissipated in distributed shear, the potential energy loss of soil flowing into the tunnel, and the work done by this soil against the tunnel support pressure. The calculations are carried out in steps of small volume loss accompanying small reduction in support pressure, after each of which the tunnel geometry is updated. In this way, each reduced tunnel support pressure is related to a complete ground displacement field. A simplified closed-form solution is also provided for the prediction of maximum surface ground settlement for the particular case of deep tunnelling. This closed-form solution is obtained by integrating the vertical equilibrium equation on the tunnel centreline from the tunnel crown up to the ground surface. These two analytical solutions have been validated against five previously published centrifuge tests. [ABSTRACT FROM AUTHOR]

Objectives: To review our experience with fetal aortic valvuloplasty (FAV) in fetuses with critical aortic stenosis (CAS) and evolving hypoplastic left heart syndrome (eHLHS), including short‐ and medium‐term postnatal outcome, and to refine selection criteria for FAV by identifying preprocedural predictors of biventricular (BV) outcome. Methods: This was a retrospective review of all fetuses with CAS and eHLHS undergoing FAV at our center between December 2001 and September 2020. Echocardiograms and patient charts were analyzed for pre‐FAV ventricular and valvular dimensions and hemodynamics and for postnatal procedures and outcomes. The primary endpoints were type of circulation 28 days after birth and at 1 year of age. Classification and regression‐tree analysis was performed to investigate the predictive capacity of pre‐FAV parameters for BV circulation at 1 year of age. Results: During the study period, 103 fetuses underwent 125 FAVs at our center, of which 87.4% had a technically successful procedure. Technical success per fetus was higher in the more recent period (from 2014) than in the earlier period (96.2% (51/53) vs 78.0% (39/50); P = 0.0068). Eighty fetuses were liveborn after successful intervention and received further treatment. BV outcome at 1 year of age was achieved in 55% of liveborn patients in our cohort after successful FAV, which is significantly higher than the BV‐outcome rate (23.7%) in a previously published natural history cohort fulfilling the same criteria for eHLHS (P = 0.0015). Decision‐tree analysis based on the ratio of right to left ventricular (RV/LV) length combined with LV pressure (mitral valve regurgitation maximum velocity (MR‐Vmax)) had a sensitivity of 96.97% and a specificity of 94.44% for predicting BV outcome without signs of pulmonary arterial hypertension at 1 year of age. The highest probability for a BV outcome was reached for fetuses with a pre‐FAV RV/LV length ratio of < 1.094 (96.4%) and for those fetuses with a RV/LV length ratio ≥ 1.094 to < 1.135 combined with a MR‐Vmax of ≥ 3.14 m/s (100%). Conclusions: FAV could be performed with high success rates and an acceptable risk with improving results after a learning curve. Pre‐FAV RV/LV length ratio combined with LV pressure estimates were able to predict a successful BV outcome at 1 year of age with high sensitivity and specificity. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. A video abstract of this article is available online here. [ABSTRACT FROM AUTHOR]

Background Glioblastoma is the most common and aggressive adult brain malignancy against which conventional surgery and chemoradiation provide limited benefit. Even when a good treatment response is obtained, recurrence inevitably occurs either locally (∼80%) or distally (∼20%), driven by cancer clones that are often genomically distinct from those in the primary tumour. Glioblastoma cells display a characteristic infiltrative phenotype, invading the surrounding tissue and often spreading across the whole brain. Cancer cells responsible for relapse can reside in two compartments of residual disease that are left behind after treatment: the infiltrated normal brain parenchyma and the sub-ventricular zone. However, these two sources of residual disease in glioblastoma are understudied because of the difficulty in sampling these regions during surgery. Patient and methods Here, we present the results of whole-exome sequencing of 69 multi-region samples collected using fluorescence-guided resection from 11 patients, including the infiltrating tumour margin and the sub-ventricular zone for each patient, as well as matched blood. We used a phylogenomic approach to dissect the spatio-temporal evolution of each tumour and unveil the relation between residual disease and the main tumour mass. We also analysed two patients with paired primary-recurrence samples with matched residual disease. Results Our results suggest that infiltrative subclones can arise early during tumour growth in a subset of patients. After treatment, the infiltrative subclones may seed the growth of a recurrent tumour, thus representing the 'missing link' between the primary tumour and recurrent disease. Conclusions These results are consistent with recognised clinical phenotypic behaviour and suggest that more specific therapeutic targeting of cells in the infiltrated brain parenchyma may improve patient's outcome. [ABSTRACT FROM AUTHOR]

Objective: To assess the immediate effects of fetal pulmonary valvuloplasty on right ventricular (RV) size and function as well as in-utero RV growth and postnatal outcome.Methods: Patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS) who underwent fetal pulmonary valvuloplasty at our center between October 2000 and July 2017 were included. Echocardiographic data obtained before and after the procedure were analyzed retrospectively (median interval after intervention, 1 (range, 1-3) days) for ventricular and valvular dimensions and ratios, RV filling time (duration of tricuspid valve (TV) inflow/cardiac cycle length), TV velocity time integral (TV-VTI) × heart rate (HR) and tricuspid regurgitation (TR) velocity. Longitudinal data were collected from only those fetuses followed up in our center. Outcome was assessed using the scoring system as described by Roman et al. for non-biventricular outcome.Results: Thirty-five pulmonary valvuloplasties were performed in our institution on 23 fetuses with PAIVS (n = 15) or CPS (n = 8). Median gestational age at intervention was 28 + 4 (range, 23 + 6 to 32 + 1) weeks. No fetal death occurred. Immediately after successful intervention, RV/left ventricular length (RV/LV) ratio (P ≤ 0.0001), TV/mitral valve annular diameter (TV/MV) ratio (P ≤ 0.001), RV filling time (P ≤ 0.00001) and TV-VTI × HR (P ≤ 0.001) increased significantly and TR velocity (P ≤ 0.001) decreased significantly. In fetuses followed longitudinally to delivery (n = 5), RV/LV and TV/MV ratios improved further or remained constant until birth. Fetuses with unsuccessful intervention (n = 2) became univentricular, all others had either a biventricular (n = 15), one-and-a-half ventricular (n = 3) or still undetermined (n = 3) outcome. Five of nine fetuses with a predicted non-biventricular outcome, in which the procedure was successful, became biventricular, while two of nine had an undetermined circulation.Conclusion: In selected fetuses with PAIVS or CPS, in-utero pulmonary valvuloplasty led immediately to larger RV caused by reduced afterload and increased filling, thus improving the likelihood of biventricular outcome even in fetuses with a predicted non-biventricular circulation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The interaction mechanisms between surface structures and tunnelling-induced ground movements were investigated through centrifuge testing. Although numerous studies have considered this soil-structure interaction problem, previous experiments have neglected important building characteristics and field data inherently contain numerous uncertainties related to the soil, the structure and the tunnelling procedure. Consequently, the interpretation of results and validation of computational models can be problematic. In this study, tunnelling beneath three-dimensional printed structural models with varying building characteristics (i.e. position, length and facade openings) was simulated in a centrifuge. The experimental results demonstrate that tunnelling induces soil displacements at the surface and subsurface that are notably altered due to nearby structures. Specifically, different amounts of vertical and horizontal ground movements, soil dilation and widening of settlement troughs were observed. Building distortions and horizontal building strains were also affected by the relative position of the building to the tunnel, the building length and the area of facade openings. The experimental results provide important data for the evaluation of current design methods and verification of computational models. [ABSTRACT FROM AUTHOR]

A series of centrifuge model tests in clay was carried out to investigate the response of an existing tunnel at different clear distances to new tunnelling. A three-dimensional (3D) staged tunnelling model was adopted to simulate a wide range of tail void volume losses for the new tunnel construction while monitoring detailed 3D soil surface settlements and tunnelling-induced strains in the existing tunnel lining. This paper also presents a detailed case study of a similar scenario in the London Underground redevelopment of Bond Street station; various state-of-the-art instrumentation methods, including fibre optic Brillouin optical time domain reflectometry, instrumented tunnel bolts and photogrammetry, were deployed to monitor the response of the existing Royal Mail tunnel due to the new tunnelling works close beneath. The combination of field and centrifuge modelling data provides important new insights into the deformation mechanisms encountered in such complex tunnelling scenarios. [ABSTRACT FROM AUTHOR]

In many nations industrial scale AD of non-agricultural waste materials (such as MSW) has not yet reached its full potential, often constrained by the lack of secure, inexpensive, high quality AD feedstocks, and markets for the resulting digestate material. We tested the output material of a high throughput novel industrial process to define its potential as an AD feedstock (based on quality and consistency). This process, designed to circumvent the constraints of source segregation while still generating segregated waste streams, resulted in the production of a temporally homogenous fibrous material with: an average moisture content of 44.2 (±2.33)%; C:N ratio of ~32.9:1 (±3.46:1), C:P ratio of ~228:1 and gross calorific value of 17.4 (±0.29) MJ/kg(DM). This material provided a CH4 yield of between 201 and 297 m³ CH4/tonne(DM) (271-401 m³ CH4/tonne(vs)) comparable to commonly used AD feedstocks. Material contaminant levels were temporally consistent (P > 0.05), (average values being Cd 0.63 (±0.19), Cu 56.3 (±7.45), Crtot 51.4 (±4.41), Hg < 0.3, Ni 28.9 (±5.17), Pb 79.2 (±23.71), Zn 202 (±44.5), total polyaromatic hydrocarbons (PAH) 2.2 (±0.3), and total polychlorinated biphenyls (PCB) (<0.2) mg/kg(DM)). Calculated digestate contaminant levels were below the median contaminant threshold limits for anaerobic digestates of all countries within the European Union i.e. of Cd 3.35, Cu 535, Crtot 535, Hg 8.15, Ni 185, Pb 397.5, Zn 2100 mg/kg(DM). We suggest that novel high throughput processes that produce high quality AD feedstocks, may have a place in further diversion of waste from landfill. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Fetal aortic valvuloplasty may prevent the progression of aortic stenosis to hypoplastic left heart syndrome and allow biventricular rather than univentricular postnatal treatment. This study aimed to investigate whether blinded simulation of a multidisciplinary team approach aids interpretation of multicenter data to uncover institutional bias in postnatal decision-making following fetal cardiac intervention for aortic stenosis. Methods The study included 109 cases of prenatally diagnosed aortic stenosis from 13 European countries, of which 32 had undergone fetal cardiac intervention. The multidisciplinary team, blinded to fetal cardiac intervention, institutional location and postnatal treatment, retrospectively assigned a surgical pathway (biventricular or univentricular) based on a review of recorded postnatal imaging and clinical characteristics. The team's decisions were the numerical consensus of silent voting, with case review when a decision was split. Funnel plots showing concordance between the multidisciplinary team and the local team's surgical choice (first pathway) and with outcome (final pathway) were created. Results In 105 cases the multidisciplinary team reached a consensus decision regarding the surgical pathway, with no decision in four cases because the available imaging records were inadequate. Blinded multidisciplinary team consensus for the first pathway matched the decision of the surgical center in 93/105 (89%) cases, with no difference in agreement between those that had undergone successful fetal cardiac intervention ( n = 32) and no ( n = 74) or unsuccessful ( n = 3) valvuloplasty (no fetal cardiac intervention) (κ = 0.73 (95% CI, 0.38-1.00) vs 0.74 (95% CI, 0.51-0.96)). However, funnel plots comparing multidisciplinary team individual decisions with those of the local teams displayed more discordance (meaning biventricular-univentricular conversion) for the final surgical pathway following fetal cardiac intervention than they did for cases without such intervention (36/74 vs 34/130; P = 0.002), and identified one outlying center. Conclusions The use of a blinded multidisciplinary team to simulate decision-making and presentation of data in funnel plots may assist in the interpretation of data submitted to multicenter studies and permit the identification of outliers for further investigation. In the case of aortic stenosis, a high level of agreement was observed between the multidisciplinary team and the surgical centers, but one outlying center was identified. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

The regulation of acid production in and the tolerance to low pH of the cariogenic bacterium Streptococcus mutans have garnered considerable attention since both of these properties contribute substantially to the virulence of this organism. Frequent or prolonged exposure to acid end products, mainly lactic acid, that are present following the consumption of dietary sugars erodes the dental enamel, thereby initiating dental caries. Here we report the involvement of the S. mutans VicK sensor kinase in both the acidogenicity and the aciduricity of this bacterium. When cultures were supplemented with glucose, the glycolytic rate of a VicK null mutant was significantly decreased compared to the glycolytic rate of the wild type (P < 0.05), suggesting that there was impaired acid production. Not surprisingly, the VicK deletion mutant produced less lactic acid, while an acid tolerance response assay revealed that loss of VicK significantly enhanced the survival of S. mutans (P < 0.05). Compared to the survival rates of the wild type, the survival rates of the VicK-deficient mutant were drastically increased when cultures were grown at pH 3.5 with or without preexposure to a signal pH (pH 5.5). Global transcriptional analysis using DNA microarrays and S. mutans wild-type UA159 and VicK deletion mutant strains grown at neutral and low pH values revealed that loss of VicK significantly affected expression of 89 transcripts more than twofold at pH 5.5 (P < 0.001). The affected transcripts included genes with putative functions in transport and maintenance of cell membrane integrity. While our results provide insight into the acid-inducible regulon of S. mutans, here we imply a novel role for VicK in regulating intracellular pH homeostasis in S. mutans. [ABSTRACT FROM AUTHOR]

This paper examines the effect that tunnel size, depth and volume loss have on greenfield soil displacements above tunnels in sandy ground. The results of a series of plane-strain centrifuge tests performed on tunnels in a dry silica sand are examined. The cover-to-diameter ratio, /, of the tunnels ranged from 1·3 to 4·4. Features of greenfield settlement trough shape, both surface and subsurface, are illustrated by examining soil displacement data obtained using an image-based deformation measurement technique. The effects of tunnel size, depth and volume loss are demonstrated, and the suitability of typical fitting curves is discussed. The complex volumetric behaviour of drained soil is illustrated by comparing tunnel volume loss with the volume loss experienced by the soil. A set of equations is developed that provide a method of evaluating the change of settlement trough shape with tunnel size, depth and volume loss. [ABSTRACT FROM AUTHOR]

The article presents a study on the impact of acid-stress-induced motilities in the virulence of enterohaemorrhagic Escherichia coli (EHEC) O157:H7. It states that environmental factors such as host-cells, temperature, and culture medium regulate the gene expression of virulence in EHEC infection. It notes that EHEC infection often results to bloody diarrhea or haemolytic uraemic syndrome (HUS). Moreover, it concludes that acid stress is essential in altering the properties of EHEC virulence.

Nuclear magnetic resonance (NMR) experiments are described for gas-fluidized granular beds, which are important systems for many materials-processing operations. Using pulsed field gradient, magnetic resonance imaging, and hyperpolarized gas NMR, detailed information is obtained for the density and motions of both grains and interstitial gas. In particular, dynamic correlations in the grain density are used to measure the bubble velocity and hyperpolarized xenon gas NMR is used to measure the bubble-emulsion exchange rate. A goal of these measurements is to verify in earth gravity first-principles theories of granular flows. [ABSTRACT FROM AUTHOR]

Solutions for the problem of tunneling effects on existing pipelines are given. The solution utilizes a boundary integral formulation for describing the elastic continuum, in conjunction with a limiting force to consider relative pullout failure. The solution requires estimation of soil and pipe elastic properties, relative pipe-soil uplift capacity, and the green field soil settlement profile given in the current paper as a modified Gaussian curve. Normalized graphs for the solution are given as a function of these input parameters. The solution method is compared and evaluated against a limited number of finite-element analysis. [ABSTRACT FROM AUTHOR]

A method is presented for estimating the maximum bending moment for continuous (or rigidly jointed) pipelines affected by tunnel-induced ground movement. The estimation can be made based on the knowledge of tunnel and pipeline geometries, the stiffness of soil and pipeline, and tunnel-induced ground deformation at the pipeline level. The method takes account of soil nonlinearity by an equivalent linear approach, in which the stiffness of the soil is evaluated based on an average deviatoric strain developed along the pipeline. The approach is conservative and promises that the bending moment is not underestimated. The validity of the method as an upper bound approximation is evaluated against centrifuge test results. [ABSTRACT FROM AUTHOR]

An elastic continuum solution and a Winkler solution of the problem of tunnelling effects on existing pipelines are given. A comparison is made between an elastic continuum solution and a closed-form Winkler solution with Vesic subgrade modulus. Although applying the Vesic expression results in the same moments and displace- ments under external loading in a Winkler system and the elastic continuum, it is found that its use is not necessarily adequate for the problem of tunnelling effects on pipelines and may not be conservative owing to possible underestimation of bending moments. An alternative expression for the subgrade modulus is provided, resulting in similar maximum bending moments in the Winkler and elastic continuum systems. [ABSTRACT FROM AUTHOR]

An elastic continuum solution and a Winkler solution of the problem of tunnelling effects on existing pipelines are given. A comparison is made between an elastic continuum solution and a closed-form Winkler solution with Vesic subgrade modulus. Although applying the Vesic expression results in the same moments and displacements under external loading in a Winkler system and the elastic continuum, it is found that its use is not necessarily adequate for the problem of tunnelling effects on pipelines and may not be conservative owing to possible underestimation of bending moments. An alternative expression for the subgrade modulus is provided, resulting in similar maximum bending moments in the Winkler and elastic continuum systems. [ABSTRACT FROM AUTHOR]

The optical properties of Al[sub x]Ga[sub 1-x]N alloys with x varied from 0 to 0.35 have been investigated by picosecond time-resolved photoluminescence (PL) spectroscopy. Our results revealed that while the PL intensity decreases with an increase of Al content, the low-temperature PL decay lifetime increases with Al content. These results can be understood in terms of the effects of tail states in the density of states due to alloy fluctuation in the Al[sub x]Ga[sub 1-x]N alloys. The Al-content dependence of the energy-tail-state distribution parameter E[sub 0], which is an important parameter for determining optical and electrical properties of the AlGaN alloys, has been obtained experimentally. The PL decay lifetime increases with the localization energy and, consequently, increases with Al content. The implications of our findings to III-nitride optoelectronic device applications are also discussed. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Abstract The intralaminar thalamic nuclei (ILn) have been implicated as a critical site of pathology in amnesia. Lesions of the ILn have been found to produce behavioral effects comparable to benzodiazepine (BDZ) receptor agonists. We compared the effects of chlordiazepoxide (CDP), a BDZ agonist, and FG 7142, a partial inverse agonist at the BDZ receptor, in rats with thalamic lesions and in unlesioned controls. Delayed matching-to sample (DMS) performances were studied during treatment with ascending doses of CDP, counterbalanced trials with 2.5 mg/kg CDP and saline, ascending doses of FG 7142, and (for unlesioned controls only) counterbalanced trials with saline and higher doses of CDP. CDP had effects similar to the ILn lesion, decreasing response speed and percent correct responding in a delay-independent fashion. These effects were additive with the impairments associated with the ILn lesion. The effects of FG 7142 were more complex. At lower doses, it increased response speed without affecting response accuracy. At higher doses, it diminished both the speed and the accuracy of DMS responding. These results support the hypothesis that ILn lesions and BDZ agonists have similar effects on DMS performance. The biphasic effects observed for FG 7142 are consistent with other evidence that low doses of this drug enhance while higher doses impair memory performance. Although DMS accuracy was not improved, the enhancement observed for response speed provides evidence that partial inverse BDZ agonists have potential utility as treatments for cognitive impairments associated with amnesia. [ABSTRACT FROM AUTHOR]

The mortality and morbidity of children with pulmonary atresia/intact ventricular septum (PA/IVS) are linked to the degree of right ventricular (RV) hypoplasia. Opening up the pulmonary valve (PV) in fetal life could result in improved growth of the R V making it amenable to biventricular repair postnatally. Successful valvulotomy of the PV was performed in a fetus with heart failure at 28 weeks. Following the procedure there was significant growth of the tricuspid valve and RV. The neonate was delivered at 38 weeks with a RV suitable for biventricular repair. In utero pulmonary valvulotomy is feasible and may change the natural history of the condition in affected fetuses with PA/IVS. [ABSTRACT FROM AUTHOR]

An abstract of the article "Fetal aortic valvuloplasty: investigating institutional bias in multicenter contributions to studies" by H. Gardiner and others is presented.