Current Deflection NDE for Defect Screening

The measurement of perturbations in the magnetic field resulting from the deflection of an injected electric current around a defect has been shown to have many potential applications in NDE. Characteristics of such a technique include through-wall sensitivity to defects at tens of millimetres of lift-off between sensor and sample, which makes the technique suitable to a number of traditionally difficult-to-inspect scenarios where extensive insulation and/or coating removal is undesirable. This paper presents a study into the feasibility of using Magnetoresistive (MR) sensors to measure current deflection from corrosion-like defects via an internal or external scan of the pipe. Prediction of the signal due to different defect geometries have been facilitated by a validated FE model, and current deflection measurements using Anisotropic MR sensors have allowed prediction of the sensitivity of the technique. The various practical challenges are explored which include the misalignment of the sensors with the target components of the magnetic field, the influence of nearby ferromagnetic objects, and the effect of pipe features such as bends and crossings. The results suggest that low-powered, inexpensive MR sensors in a gradiometric configuration can be used to measure current deflection from defects occurring on the inner or outer wall of pipes carrying a few amps of current while the coating, insulation and (non-ferromagnetic) cladding remain intact. This has many potential applications, particularly in the oil and gas and power industries

The Impact of a Model Cities Program on the Convergence of Crime Rates in a Model City Area and Residual Areas

One purpose of the national Model Cities Program was to reduce the incidence of crime and delinquency in poverty blighted areas to levels prevailing in the remainder of the community. A measurable goal projected by the Austin program was to reduce crime in its Model City Area (in comparison to the rest of the city) by at least 8.73 per cent during the operational years of the program. The central problem of the study was to examine the relationships between official crime rates in the Austin Model City Area in comparison to residual areas of the city. Robbery, burglary, and auto theft rates were singled out for intensive study over the six year operational period of the program to see if they were converging with comparable rates in the rest of the city. Ultimate implication: the Model Cities Program was probably a contributing factor in the reduction of selected crimes in the Model Neighborhood and census tracts containing it

Study of Metal Magnetic Memory (MMM) Technique Using Permanently Installed Magnetic Sensor Arrays

The Metal magnetic memory (MMM) technique is marketed as a non-destructive testing method to evaluate stress concentration for ferromagnetic materials by measuring variations of the self-magnetic leakage field (SMLF) distribution on the specimen surface. This method has been implemented as a periodic screening inspection tool by several companies, and has been reported to be capable of detecting stress concentration in some instances. However, recent literature has suggested that the performance can be unreliable, with many false-calls; however, the reason for the false calls has not been satisfactorily investigated. In this paper, the normal and tangential components of the stress induced SMLF on the surface of specimens made from L80 steel, which is commonly used for pipes in the petrochemical industry, were measured by two permanently installed magnetic sensor arrays under the earth’s magnetic field. The results show that the SMLF changes are very small (about 10 ~ 30 A/m) in all cases for the material tested and occur mainly in first elastic load cycle. A Finite Element (FE) model has been used to predict the spatial distribution of the magnetic field due to localized MMM. The FE studies show that the defect size and the applied background magnetic field will influence the SMLF signal; however, the signal due to MMM could be swamped by any ferromagnetic material near to the magnetic sensors. The simulation and experimental results demonstrate the high probability of false calls with the MMM technique even if there were a significant MMM effect in the material used

Genetic variability in wild and domestic populations of Inga edulis Mart. (Fabaceae) in Peruvian Amazon

Human activity in the Peruvian Amazon causes native vegetation fragmentation into smaller units resulting on the increase of agricultural systems. Understanding the level, the structure and the origin of morphologic within and among populations variation is essential for planning better management strategies aimed at sustainable use and conservation of Inga edulis Mart. species. We evaluated the genetic variability in wild and domestic population to unfold cultivation changes over the species genetic resources. We have studied 400 adult trees: 200 cultivated on arable land and 200 wild growing in untouched lowland rain forest. The individuals were randomly selected. Sampling sites were selected and defined on the basis of the geographical coordinates: longitude, latitude and altitude. Phenotypic variation was monitored using the proposed descriptor of qualitative and quantitative features (e.g., weight of hundred seeds). For each individual a voucher specimen was kept. The total genomic DNA was extracted from young leaves, conserved in silica gel, with INVITEK, Invisorb ®Spin Plant Mini Kit. Samples were then genotyped with five microsatellite (SSR) loci. One locus (Pel5) was cross-transferred, developed previously for Pithecellobium elegans. The remaining four loci (Inga03, 05, 08, 33) were previously developed for the species. Polymerase chain reaction (PCR) was made using a Biometra® T1 Thermocycler using the following profile: 95 °C for 2 min; 95°C for 15 s, 55/59 °C for 30 s, 72 °C for 30 s, 30 cycles; 72 °C for 15 min. The PCR products were fluorescently labelled. The visualization of fragments was carried out according to standard protocols on genetic analyser, ABI PRISM® 310 (Applied Biosystems), using ABI GENESCAN and GENOTYPER software. The phenotypic and genotypic results of wild versus domestic populations are under evaluation to verify if cultivation is altering the allelic variation considering that morphology is considerably changed.Czech Development Cooperation Project entitled “Sustainable use of natural resources in Peruvian Amazon” Project No. 23/MZe/B/07-10; The Academy of Science of The Czech Republic and the National Council for Science, Technology and Technological Innovation, Peru, binational project entitled “Morphological and genetic diversity of indigenous tropical trees in the Amazon – model study of Inga edulis Mart. in Peruvian Amazon”; Foundation “Nadace Nadání Josefa, Marie a Zdeňky Hlávkových”, Czech Republi

The Color of Childhood: The Role of the Child/Human Binary in the Production of Anti-Black Racism

The binary between the figure of the child and the fully human being is invoked with regularity in analyses of race, yet its centrality to the conception of race has never been fully explored. For most commentators, the figure of the child operates as a metaphoric or rhetorical trope, a non-essential strategic tool in the perpetuation of White supremacy. As I show in the following, the child/human binary does not present a contingent or merely rhetorical construction but, rather, a central feature of racialization. Where Black peoples are situated as objects of violence it is often precisely because Blackness has been identified with childhood and childhood is historically identified as the archetypal site of naturalized violence and servitude. I proceed by offering a historical account of how Black peoples came to inherit the subordination and dehumanization of European childhood and how White youth were subsequently spared through their partial categorization as adults

A new urban landscape in East–Southeast Asia, 2000–2010

East–Southeast Asia is currently one of the fastest urbanizing regions in the world, with countries such as China climbing from 20 to 50% urbanized in just a few decades. By 2050, these countries are projected to add 1 billion people, with 90% of that growth occurring in cities. This population shift parallels an equally astounding amount of built-up land expansion. However, spatially-and temporally-detailed information on regional-scale changes in urban land or population distribution do not exist; previous efforts have been either sample-based, focused on one country, or drawn conclusions from datasets with substantial temporal/spatial mismatch and variability in urban definitions. Using consistent methodology, satellite imagery and census data for >1000 agglomerations in the East–Southeast Asian region, we show that urban land increased >22% between 2000 and 2010 (from 155 000 to 189 000 km2), an amount equivalent to the area of Taiwan, while urban populations climbed >31% (from 738 to 969 million). Although urban land expanded at unprecedented rates, urban populations grew more rapidly, resulting in increasing densities for the majority of urban agglomerations, including those in both more developed (Japan, South Korea) and industrializing nations (China, Vietnam, Indonesia). This result contrasts previous sample-based studies, which conclude that cities are universally declining in density. The patterns and rates of change uncovered by these datasets provide a unique record of the massive urban transition currently underway in East–Southeast Asia that is impacting local-regional climate, pollution levels, water quality/availability, arable land, as well as the livelihoods and vulnerability of populations in the regio

HPV sensitizes OPSCC cells to cisplatin-induced apoptosis by inhibiting autophagy through E7-mediated degradation of AMBRA1

Oropharyngeal squamous cell carcinoma (OPSCC) is an increasing world health problem with a more favorable prognosis for patients with human papillomavirus (HPV)-positive tumors compared to those with HPV-negative OPSCC. How HPV confers a less aggressive phenotype, however, remains undefined. We demonstrated that HPV-positive OPSCC cells display reduced macroautophagy/autophagy activity, mediated by the ability of HPV-E7 to interact with AMBRA1, to compete with its binding to BECN1 and to trigger its calpain-dependent degradation. Moreover, we have shown that AMBRA1 downregulation and pharmacological inhibition of autophagy sensitized HPV-negative OPSCC cells to the cytotoxic effects of cisplatin. Importantly, semi-quantitative immunohistochemical analysis in primary OPSCCs confirmed that AMBRA1 expression is reduced in HPV-positive compared to HPV-negative tumors. Collectively, these data identify AMBRA1 as a key target of HPV to impair autophagy and propose the targeting of autophagy as a viable therapeutic strategy to improve treatment response of HPV-negative OPSCC. Abbreviations: AMBRA1: autophagy and beclin 1 regulator 1; CDDP: cisplatin (CDDP); FFPE: formalin-fixed paraffin-embedded (FFPE); HNC: head and neck cancers (HNC); HPV: human papillomavirus (HPV); hrHPV: high risk human papillomavirus (hrHPV); OCSCC: oral cavity squamous carcinomas (OCSSC); OPSCC: oropharyngeal squamous cell carcinoma (OPSCC); OS: overall survival (OS); qPCR: quantitative polymerase chain reaction; RB1: RB transcriptional corepressor 1; ROC: receiver operating characteristic curve (ROC)

A review of selected topics in physics based modeling for tunnel field-effect transistors

The research field on tunnel-FETs (TFETs) has been rapidly developing in the last ten years, driven by the quest for a new electronic switch operating at a supply voltage well below 1 V and thus delivering substantial improvements in the energy efficiency of integrated circuits. This paper reviews several aspects related to physics based modeling in TFETs, and shows how the description of these transistors implies a remarkable innovation and poses new challenges compared to conventional MOSFETs. A hierarchy of numerical models exist for TFETs covering a wide range of predictive capabilities and computational complexities. We start by reviewing seminal contributions on direct and indirect band-to-band tunneling (BTBT) modeling in semiconductors, from which most TCAD models have been actually derived. Then we move to the features and limitations of TCAD models themselves and to the discussion of what we define non-self-consistent quantum models, where BTBT is computed with rigorous quantum-mechanical models starting from frozen potential profiles and closed-boundary Schr\uf6dinger equation problems. We will then address models that solve the open-boundary Schr\uf6dinger equation problem, based either on the non-equilibrium Green's function NEGF or on the quantum-transmitting-boundary formalism, and show how the computational burden of these models may vary in a wide range depending on the Hamiltonian employed in the calculations. A specific section is devoted to TFETs based on 2D crystals and van der Waals hetero-structures. The main goal of this paper is to provide the reader with an introduction to the most important physics based models for TFETs, and with a possible guidance to the wide and rapidly developing literature in this exciting research field

Monitoring the EU protected Geomalacus maculosus (Kerry Slug): what are the factors affecting catch returns in open and forested habitats?

Geomalacus maculosus is a slug species protected under EU law with a distribution limited to the west of Ireland and north-west Iberia. The species, originally thought to be limited within Ireland to deciduous woodland and peatland, has been found in a number of commercial conifer plantations since 2010. While forest managers are now required to incorporate the protection of the species where it is present, no clear species monitoring protocols are currently available. This study examines the efficacy of De Sangosse refuge traps across three habitats frequently associated with commercial forest plantations in Ireland and compares them with hand searching, a commonly used method for slug monitoring. Catch data during different seasons and under different weather conditions are also presented. Results indicate that autumn is the optimal time for sampling G. maculosus but avoiding extremes of hot or cold weather. While refuge traps placed at 1.5 m on trees in mature conifer plantations and directly on exposed rock in blanket peatlands result in significantly greater catches, hand searching is the most successful approach for clear-fell areas. Hand searches in clear-fell preceded by rain are likely to result in greater numbers caught. The results of this study form, for the first time, the basis for G. maculosus monitoring guidelines for forestry managers. © 2016, The Ecological Society of Japa