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Structure-from-motion (SfM) modeling has dramatically increased the speed of generating geometrically accurate orthophoto mosaics of paleoseismic trenches, but some aspects of this technique remain time and labor intensive. Model accuracy relies on control points to establish scale, reduce distortion, and orient 3D models. Traditional SfM methods use total station or Global Navigation Satellite System (GNSS) surveys to constrain models, but collecting control points along a vertical trench wall is often inhibited by poor line of sight to the survey sensor or limited sky view and requires many hours in the field and office. We used physical scale bars printed with coded targets to constrain SfM models of a dusty, 46-m-long trench excavation across the Teton fault (Wyoming, U.S.A.). We present a workflow for generating quick and accurate 3D SfM models and orthophoto mosaics and compare the effectiveness of using scale bar, GNSS, and total-station control in the models. Our results show that the scale bar model deviates from total station survey points by an average of 3.1 cm (maximum of 5.3 cm). In addition, the scale-bar model only deviates an average of 1.7 cm (maximum 3.5 cm) when compared to the best model alternative, the SfM model controlled by the total station survey. Scale bars eliminate several hours needed to collect and incorporate control points from total station or GNSS surveys and significantly simplify the workflow, at the cost of slightly increased 3D model and orthophoto mosaic error. Our results further suggest that trench models can be constrained with at least four physical scale bars, but using five to six physical scale bars provides redundant control for field deployment and model optimization. The scale bar method for paleoseismic trenches proves to be portable and fast, minimizes the need for specialized survey equipment, and maintains model accuracy needed for mapping trench walls.

This paper provides an overview of typical non-destructive test (NDT) procedures currently used for pavement structural evaluation applications. In particular, surface deflection measurements, spectral analysis of surface waves (SASW), and ground penetrating radar (GPR) approaches are described and discussed. Data interpretation and application, including problems encountered with each type of measurement, are also covered. Potential future developments in this field are discussed.

Knowledge of the state of stress in Earth’s crust is key to understanding the forces and processes responsible for earthquakes. Historically, low rates of natural seismicity in the central and eastern United States have complicated efforts to understand intraplate stress, but recent improvements in seismic networks and the spread of human-induced seismicity have greatly improved data coverage. Here, we compile a nationwide stress map based on formal inversions of focal mechanisms that challenges the idea that deformation in continental interiors is driven primarily by broad, uniform stress fields derived from distant plate boundaries. Despite plate-boundary compression, extension dominates roughly half of the continent, and second-order forces related to lithospheric structure appear to control extension directions. We also show that the states of stress in several active eastern United States seismic zones differ significantly from those of surrounding areas and that these anomalies cannot be explained by transient processes, suggesting that earthquakes are focused by persistent, locally derived sources of stress. Such spatially variable intraplate stress appears to justify the current, spatially variable estimates of seismic hazard. Future work to quantify sources of stress, stressing-rate magnitudes and their relationship with strain and earthquake rates could allow prospective mapping of intraplate hazard.

When advised that I had been proposed to receive the Institute’s Hothersall Memorial Award and invited to present the Hothersall Memorial Lecture at the 2016 AGM my thought was what would be my the...

The coronavirus disease 2019 crisis has caused a sharp rise in demand for ventilators and respiratory therapists (RTs) who are trained to operate them. Shortages of these resources in hospitals have put patients who need them at increased risk. In this Perspective, researchers describe a model they developed to help assess needs and to allocate ventilators and RTs efficiently among hospitals in order to minimize patient wait time.

Flip-chip heterogeneously integrated n-p-n InGaP/GaAs heterojunction bipolar transistors (HBTs) with integrated thermal management on wide-bandgap AlN substrates followed by GaAs substrate removal are demonstrated. Without thermal management, substrate removal after integration significantly aggravates self-heating effects, causing poor $I$ – $V$ characteristics due to excessive device self-heating. An electrothermal codesign scheme is demonstrated that involves simulation (design), thermal characterization, fabrication, and evaluation. Thermoreflectance thermal imaging, electrical-temperature sensitive parameter-based thermometry, and infrared thermography were utilized to assess the junction temperature rise in HBTs under diverse configurations. In order to reduce the thermal resistance of integrated devices, passive cooling schemes assisted by structural modification, i.e., positioning indium bump heat sinks between the devices and the carrier, were employed. By implementing thermal heat sinks in close proximity to the active region of flip-chip integrated HBTs, the junction-to-baseplate thermal resistance was reduced over a factor of two, as revealed by junction temperature measurements and improvement of electrical performance. The suggested heterogeneous integration method accounts for not only electrical but also thermal requirements providing insight into realization of advanced and robust III-V/Si heterogeneously integrated electronics.

Research in educational leadership and management spans settings from early childhood to tertiary education and life-long learning. From its mid-20th-century beginnings as a tool for organizing educational systems, the wide range of methodologies in present use reflects the shifting focus of the field. The current mix of quantitative and qualitative approaches indicates differing epistemological stances and a range of purposes from instrumental responses to government policy initiatives, through investigation of issues of social justice, to personal enquiry into leadership influence on environments for learning. Research in the field encompasses the values and dilemmas underpinning educational leadership roles, the enactment of middle leadership, teacher leadership and student leadership, and includes leaders conducting research to improve their own practice. Multiple aspects of decision-making are involved in educational leadership research. The philosophical assumptions of researchers inform their positivist or interpretivist stance and the associated choices of quantitative or qualitative methodology. The external drivers of the investigation, together with its purpose and scope, influence the choice of research approach —for example, data-mining, survey, case study, action research—and technique—interview, questionnaire, documentary analysis, narrative, and life-history. These approaches and techniques in turn invite a range of analytical methods, from statistical modeling, systematic qualitative data analysis and discourse analysis to auto-ethnographic critical reflection and reflective narrative. The interpretation of the analysis hinges on the purpose of the research: to understand, inform, improve, or bring about change. Twenty-first-century challenges for the field include expanding theory beyond a largely Western-centric focus; responding to the development of new theories of leadership, including the voice of non-leaders in perspectives on leadership; ensuring that research informs policy rather than vice versa; and addressing the sheer volume and nature of data available through emerging technologies.

California Senate Bill 1953 requires structural and nonstructural upgrades to hospital buildings to enhance resilience to seismic events. This report estimates the costs to hospitals of compliance, focusing on the 2030 deadline. The potential costs have raised significant concerns regarding the financial burden on hospital systems and the opportunity costs associated with hospitals investing large pools of capital to implement seismic upgrades.

Our teacher leadership story comes from two schools collaborating on a New Zealand Teacher Led Innovation Fund (TLIF) project exploring the effect of student-led learning practices on literacy achievement within modern learning environments (MLEs). Our rationale is that learning which is individualised for all learners leads to more equitable outcomes for all. It also enables student ownership of learning, which in turn increases success for all learners, measured through improved student engagement, positive shifts in attitude, and improved progress and achievement. We undertook two cycles of participatory action-based inquiry to find out how successful collaboration and student ownership within the MLEs could impact on literacy engagement and achievement. We noted considerable progress in the development of key competencies, influenced by the transfer of ownership from teacher to student through choice, sharing of the curriculum, and engagement with the wider range of resources readily available in an MLE. Giving students a say in their topic and context increased their engagement and led to improved outcomes in literacy achievement. The support provided by our school management for teacher-leadership of the innovations has enabled research-informed student-led pedagogy to be developed at both schools.

This paper presents the recommendations of the Global Bioanalytical Consortium Harmonization Team on method transfer, partial validation, and cross validation. These aspects of bioanalytical method validation, while important, have received little detailed attention in recent years. The team has attempted to define, separate, and describe these related activities, and present practical guidance in how to apply these techniques.

Coastlines above subduction zones slowly emerge from the sea despite repeated drowning by great, shallow earthquakes. Analysis of the Chilean coast suggests that moderate-to-large, deeper earthquakes may be responsible for the net uplift.

Step-stress experiments on high-voltage Npn InGaP/GaAs HBTs are shown to reveal a number of degradation mechanisms, singly or in combinations: defect buildup in the emitter depletion region, defect buildup in the neutral base region, possible degradation of Ohmic contacts or increase in epitaxial layer resistances. Defect buildup in the emitter depletion region often precedes other types of degradation. Two less commonly reported degradation mechanisms are also suggested: base Ohmic metal punch-through to the collector and deterioration of the die attach material. It was found that the vast majority of devices failed within 5% of a maximum attainable power level, but when stressed just shy of this catastrophic level, electrical characteristics typically degraded gradually.

This article explores challenges in ensuring effective student transition from school or college to university. It examines the complex liaison needed for students to progress to appropriate courses, settle into university life and succeed as higher education learners. Secondary data (international literature on transition and the formation of learner identity) are analysed to identify underpinning concepts. Primary data are taken from two studies of student transition in England using student and staff surveys, student focus groups, staff interviews and staff–student conferences that discussed selected project data sets. The article goes on to offer a model of the process of transition and the formation of learner identity. It proposes that the development of higher education learner identity is essential to student achievement and is initially encouraged where schools, colleges and universities adopt integrated systems of transition. This has clear implications for practice for higher education administ...

SUMMARY. Ornithobacterium rhinotracheale is a gram-negative bacterium responsible for the sporadic outbreaks of airsacculitis in poultry, accounting for millions of dollars in losses to the poultry industry annually. Although the organism was originally classified as non–b-hemolytic, recent North American field isolates of O. rhinotracheale obtained from pneumonic lungs and air sacs indicated hemolytic activity on blood agar plates upon extended incubation for 48 hr at room temperature in air after initial incubation at 37 C for 48 hr under 7.5% CO2. This report characterizes the b-hemolytic activity of O. rhinotracheale isolates by using in vitro kinetic hemolysis assays with sheep red blood cells, western blotting with leukotoxin-specific monoclonal antibodies, and isobaric tagging and relative and absolute quantitative (iTRAQ) analysis of O. rhinotracheale outer membrane protein digest preparations. The kinetic analyses of the hemolytic activity with red blood cells indicated that the protein is a pore former. iTRAQ analysis with membrane preparations revealed four peptides with homolog yt oMannheimia haemolytica leukotoxin and two peptides with homology to Actinobacillus actinoacetemcomitans leukotoxin. This is the first report that North American field isolates of O. rhinotracheale may express a hemolysin-like activity.

Professional identities in further education (FE) colleges and schools in England have been substantially affected by recent educational reform; additionally, recent reform of provision for the 14–19 age group requires close collaboration between the two sectors. Drawing on case-study data from four English FE colleges, this paper takes as its empirical base an analysis of professional identities of middle leaders in FE colleges in order to explore implications for professional practice in both colleges and schools. Three elements of professional identity are proposed and examined: professional values (What I profess), professional location (The profession to which I belong) and professional role (My role within the institution). These are used to explore commonality, difference and differential status across middle managers holding a range of roles in FE, and a model for analysing professional practice is proposed. The study indicates problems of professional identity that need to be resolved if the two ...

The purpose of this article is to exemplify and enhance the place of modelling as a qualitative process in educational research. Modelling is widely used in quantitative research as a tool for analysis, theory building and prediction. Statistical data lend themselves to graphical representation of values, interrelationships and operational systems. This article argues that qualitative data can likewise be modelled, to enable further analysis of the phenomenon investigated, to stimulate theorising about the relationship of factors within the modelled system, and to enable predictions for future scenarios to be formulated. Although this approach has been advocated by qualitative research theorists, it is not commonly used in the field of educational management. The extended example offered in this article therefore demonstrates how modelling can be used as both a conceptual and a practical tool in this field of study, enabling both the construction of theory and the process of organisational development and...

Over the past two years noteworthy experimental and theoretical progress has been made towards the top-level scientific question for the US programme on heavy-ion-fusion-science and high energy density physics: ‘How can heavy-ion beams be compressed to the high intensity required to create high energy density matter and fusion conditions?’ New results in transverse and longitudinal beam compression, high-brightness transport and beam acceleration will be reported. Central to this campaign is final beam compression. With a neutralizing plasma, we demonstrated transverse beam compression by an areal factor of over 100 and longitudinal compression by a factor of >50. We also report on the first demonstration of simultaneous transverse and longitudinal beam compression in plasma. High beam brightness is key to high intensity on target, and detailed experimental and theoretical studies on the effect of secondary electrons on beam brightness degradation are reported. A new accelerator concept for nearterm low-cost target heating experiments was invented, and the predicted beam dynamics validated experimentally. We show how these scientific campaigns have created new opportunities for interesting target experiments in the warm dense matter regime. Finally, we summarize progress towards heavy-ion fusion, including the demonstration of a compact driver-size high-brightness ion injector. For all components of our high intensity campaign, the new results have been obtained via tightly coupled efforts in experiments, simulations and theory.

Arecent study of middle managers in English further education (FE) colleges (Briggs, 2004 and in preparation) explored the concept of professionalism as displayed by the various types of manager in the study. The study tracked the shifting patterns of professional identity in the sector.Within any one college, individual managers may hold differing constructs of professionalism; however, the effective function of the organisation depends upon mutual understanding which enables middle managers to value each other’s professional identity and work successfully together. Issues of professional identity are important to organisational leadership, as they lie at the meeting-point of agency and structure. A person’s professional identity is based upon their personal perceptions of self-image and self-efficacy in relation to their working context (Busher, 2005). This identity is central to the individual's sense of agency (Busher, 2005; Giddens, 1991), developed through interactions with others in their working context in constructing social systems and structures (Giddens, 1984). Professional identity is thus both a product and an agent of the systems and structures within which the individual's working life is located.

Beta titanium alloys have been available since the 1950s (Ti-13V-11Cr-3Mo or B120VCA), but significant applications of these alloys, beyond the SR-71 Blackbird, have been slow in coming. The next significant usage of a β alloy did not occur until the mid-1980s on the B-1B bomber. This aircraft used Ti-15V-3Cr-3Al-3Sn sheet due to its capability for strip rolling, improved formability, and higher strength than Ti-6Al-4V. The next major usage was on a commercial aircraft, the Boeing 777, which made extensive use of Ti-10V-2Fe-3Al high-strength forgings. Ti-15V-3Cr-3Al-3Sn environmental control system ducting, castings, and springs were also used, along with Ti-3Al-8V-6Cr-4Mo-4Zr (β-C) springs. Beta-21S was also introduced for high-temperature usage. More recent work at Boeing has focused on the development of Ti-5Al-5Mo-5V-3Cr, a high-strength alloy that can be used at higher strength than Ti-10V-2Fe-3Al and is much more robust; it has a much wider, or friendlier, processing window. This, along with additional studies at Boeing, and from within the aerospace industry in general will be discussed in detail, summarizing applications and the rationale for the selection of this alloy system for aerospace applications.

A contacted electroreflectance technique was used to investigate AlGaN/GaN heterostructures and their intrinsic electric field-induced properties. By studying variations in the electroreflectance with applied field, spectral features associated with the AlGaN barrier, the two-dimensional electron gas at the interface, and bulk GaN were identified. Barrier-layer composition and electric field were determined from the AlGaN Franz–Keldysh oscillations. For a high mobility heterostructure grown on SiC, measured AlGaN polarization electric field and two-dimensional electron gas density approached values predicted by a standard bandstructure model. The two-dimensional electron gas produced a broad, field-tunable first derivative electroreflectance feature. With a dielectric function calculation, we describe the line shape and relative amplitude of the two-dimensional electron gas electroreflectance feature for a wide range of electron density and applied field values.

The thermal stability of Au/Ti/WSi x contacts on 4H-SiC was examined by Auger electron spectroscopy and current–voltage measurements. The silicide-based contacts on SiC are found to exhibit improved thermal stability compared to pure W contacts. The Au/Ti/WSi x contacts show a maximum Schottky barrier height of ∼1.15 eV as obtained from current–voltage ( I – V ) measurements. After 500 °C anneals, the Ti diffuses to the surface of the contact structure, followed by a Au-rich layer and finally the WSi x . After 1000 °C anneals, the Ti and Au showed significant mixing. Particulates formed on the surface in the latter case were Au-rich phases.

The pathophysiology of infantile hydrocephalus is poorly understood, and shunt treatment does not always lead to a normal neurological outcome. To investigate some of the neurochemical changes in infantile hydrocephalus and the response to shunt treatment, we have used high-resolution 1H-NMR spectroscopy to analyze extracts of cerebral cortex from H-Tx rats, which have inherited hydrocephalus with an onset in late gestation. Hydrocephalic rats and rats with shunts placed at either 4 or 12 days after birth were studied at 21 days after birth, together with age-matched control littermates. In hydrocephalic rats there was a 46–62% reduction in the following compounds: myo-inositol, creatine, choline-containing compounds, N-acetyl aspartate, taurine, glutamine, glutamate, aspartate, and alanine. Phosphocreatine, glycine, GABA, and lactate were also reduced but not significantly. These changes are consistent with neuronal atrophy rather than ischemic damage. In hydrocephalic rats that received shunt treatment at 4 days, there were no significant reductions in any chemicals, indicating a normal complement of neurons. However, some compounds, particularly taurine, were elevated above control. After treatment at 12 days, N-acetyl aspartate and aspartate remained significantly reduced, suggesting continued neuronal deficiency.

Al0.2Ga0.8N/GaN HEMTs have been fabricated from MOCVD-grown epilayers on (0 0 0 1) sapphire substrates. DC current densities from 0.5 to ∼1 A/mm were achieved for gate lengths ranging from 0.75 to 0.1 μ m. A maximum transconductance of 207 mS/mm was measured for short gate length devices. From s-parameter measurements, ft of 59 GHz and fmax of 90 GHz were extracted. Load pull results from 0.25×150 μm 2 gate dimension devices indicated an output power density of 2.75 W/mm at 3 GHz and 1.7 W/mm at 10 GHz. Small signal modeling of the measured s-parameters is also presented.

Emitter orientation effects in AlGaAs/GaAs heterojunction bipolar transistors (HBTs) in which DC current gain was greater for the [0 1 1] emitter orientation compared to the [0 1 1 ] orientation were previously attributed to the piezoelectric effect, however no effects of dielectric overlayers were examined. In this work, we establish that for InGaP/GaAs HBTs, dielectric passivation effects can be as important as the piezoelectric effect. Non-self-aligned InGaP/GaAs HBTs with ECR SiON dielectric deposited at 25 °C exhibited greater stress and showed less current gain difference and lower base current ideality factors for these orientations than identical HBTs that were passivated with plasma enhanced chemical vapor deposition (PECVD) SiN dielectric. Non-self-aligned HBTs with ECR SiON passivation also showed slightly better rf performance for the [0 1 1] orientation with ft of 48 GHz compared to ft of 44 GHz for the [0 1 1 ] orientation. These differences in dielectrics are attributed to higher dielectric-induced damage in emitter–base space-charge region for the PECVD SiN film.

The temperature and gate length effects on dc performance of AlGaN/GaN high-electron mobility transistors (HEMTs) grown on AlN/SiC templates or sapphire substrates are reported. The defect density in the structures grown on the AlN/SiC template is significantly lower than those grown on sapphire, as measured by transmission electron microscopy. Reverse breakdown voltages above 40 V were obtained for 0.25 μm gate length devices on both types of substrate. Extrinsic transconductances of ∼200 mS/mm for HEMTs on sapphire and ∼125 mS/mm for devices on AlN/SiC were achieved, with the latter devices showing significantly lower self-heating effects. Both types of HEMTs showed similar trends of drain current and transconductance with increasing temperature. There was a clear signature of optical phonon scattering as the dominant scattering mechanism from room temperature to 300 °C.

Pasteurella multocida serotype B:2 is the causative agent of hemorrhagic septicemia in cattle and buffaloes in Asia. It is an acute fatal disease and is considered one of the most economically important diseases in this region of the world. We present here the draft genome sequences of strains 2213 and 3213 of P. multocida .

The DC performance of AlGaN/GaN high electron mobility transistors grown by plasma-assisted molecular beam epitaxy was investigated for gate lengths in the range 0.1–1.2 μm. On 0.25 μm gate length devices we obtained 40 V DS operation with >50 mA peak I D . The peak drain current density was 0.44 A/mm for 100 μm gate width devices with 1.2 μm gate lengths. The extrinsic transconductance ( g m ) decreased with both gate length and gate width and was ⩾75 mS/mm for all gate widths for 0.25 μm devices. E-beam written gates typically produced a slightly lower Schottky barrier height than optically patterned gates.

The aim of this study was to retrospectively review the clinical presentation, diagnostic features, in particular cervical vestibular evoked myogenic potentials (cVEMPs), and the outcomes of surgical repair for superior semicircular canal dehiscence syndrome (SSCDS). SSCDS is a well-described syndrome of auditory and vestibular symptoms due to a bony dehiscence of the superior semicircular canal in the middle cranial fossa. A series of six procedures on five patients with SSCDS who underwent surgical repair via a middle fossa craniotomy were retrospectively reviewed. Preoperative and postoperative audiometric and vestibular symptoms as well as investigation findings were reviewed. Auditory and vestibular symptoms improved and hearing was preserved in all patients. The low frequency pseudo-conductive loss was corrected in four out of five patients, and the lowered preoperative cVEMP thresholds normalised following successful middle cranial fossa repair. In this series, middle fossa repair of SSCD was safe and effective with excellent sensorineural hearing preservation.

Plankton survey data from 1982, 1985 and 1995 were used to estimate the annual production of Nephrops norvegicus (L.) larvae in the Irish Sea. The larval abundance data from each set of surveys were analysed using the same temperature-to-stage-duration relationships. The production of larvae was similar in all 3 yr at approx. 360 × 109 Stage I larvae per year. The estimated production in the eastern Irish Sea was 5% of the value for the western Irish Sea. This corresponded well to the sizes of the fisheries and the relative areas of the mud patches. Larvae in both areas were found to hatch over 5½ wk, centred on the first week in May. The time lag between onset of production of each stage reflected the estimated stage durations, but the lag between maximum production of each stage was much shorter than expected.

The influx and death of polymorphonuclear leukocytes within the infected lung are hallmarks of bovine pasteurellosis. Recent reports have shown that thePasteurella haemolyticaleukotoxin (LKT) and other RTX toxins bind β2-integrins on target cells. In this study we demonstrate that exposure of bovine neutrophils to recombinant bovine interleukin-1β upregulates β2-integrins (CD11a/CD18), which in turn enhance the binding and amplify the biological effects of partially purified LKT on these cells. LKT binding and cytotoxicity were inhibited by addition of an anti-integrin antibody (CD11a/CD18). These findings help to clarify the early events that occur in bovine pasteurellosis and support the hypothesis that inflammatory mediators might increase the severity of pasteurellosis by causing upregulation of β2-integrins that serve as an LKT receptor on bovine neutrophils.

Learning Resource Centres (LRCs) are an increasingly common provision in Further Education Colleges. As they have derived from other types of open‐access learning facilities — libraries, Open Learning centres, subject‐based workshops — there is no common pattern of management. Rugby College set up a small facility in 1996, with a view to further expansion the following year. The study was used to support the developments, and as a management tool for the expanded Learning Resource Centre. Students attending the College in 1997 were surveyed to produce profiles of users and non‐users of the existing facility. Attractions and constraints upon use were examined in more detail through interviews with key members of the College staff. From the profiles generated by both surveys, a succession of models were built, showing the interaction of factors which influence utilisation. The key elements were: the College infrastructure; methods of curriculum delivery; the physical and social provision of the fac...

A survey of ohmic contact materials and properties to GaAs, InP, GaN will be presented along with critical issues pertaining to each semiconductor material. Au-based alloys (e.g., GeAuNi for n-type GaAs) are the most commonly used contacts for GaAs and InP materials for both n- and p-type contacts due to the excellent contact resistivity, reliability, and usefulness over a wide range of doping levels. Research into new contacting schemes for these materials has focused on addressing limitations of the conventional Au-alloys in thermal stability, propensity for spiking, poor edge definition, and new approaches for a non-alloyed contact. The alternative contacts to GaAs and InP include alloys with higher temperature stability, contacts based on solid phase regrowth, and contacts that react with the substrate to form lower bandgap semiconductors alloys at the interface. A new area of contact studies is for the wide bandgap group III-Nitride materials. At present, low resistivity ohmic contact to p-type GaN has not been obtained primarily due to the large acceptor ionization energy and the resultant difficulty in achieving high free hole concentrations at room temperature. For n-type GaN, however, significant progress has been reported with reactive Ti-based metalization schemes or the use of graded InGaN layers. The present status of these approaches will be reviewed.