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A 128 $\times $ 128 single-photon avalanche diode (SPAD) motion detection-triggered time-of-flight (ToF) sensor is implemented in STMicroelectronics 40 nm CMOS SPAD foundry process. The sensor combines vision and ToF ranging functions to acquire depth frames only when inter-frame intensity changes are detected. The 40 $\mu \text{m}\,\,\times $ 20 $\mu \text{m}$ pixels integrate two 16-bit time-gated counters to acquire ToF histograms and repurpose them to compare two vision frames without the requirement for additional out-of-pixel frame memory resources. An embedded column-parallel ToF and vision processor performs on-chip vision frame comparison and binary frame output compression as well as controlling the time-resolved histogram sampling. The sensor achieves a maximum 32.5 kframes/s in vision modality and 500 frames/s in motion detection-triggered ToF over a measured 3.5 m distance with 1.5 cm accuracy. The vision function reduces the sensor power consumption by 70% over continuous ToF operation and allows the sensor to gate the ToF laser emitter to reduce the system power when no motion activity is observed.

Nonlinear optical devices and their implementation into modern nanophotonic architectures are constrained by their usually moderate nonlinear response. Recently, epsilon-near-zero (ENZ) materials have been found to have a strong optical nonlinearity, which can be enhanced through the use of cavities or nano-structuring. Here, we study the pump dependent properties of the plasmon resonance in the ENZ region in a thin layer of indium tin oxide (ITO). Exciting this mode using the Kretschmann-Raether configuration, we study reflection switching properties of a 60 nm layer close to the resonant plasmon frequency. We demonstrate a thermal switching mechanism, which results in a shift in the plasmon resonance frequency of 20 THz for a TM pump intensity of 70 GW cm

Nonlinear optical devices and their implementation into modern nanophotonic architectures are constrained by their usually moderate nonlinear response. Recently, epsilon-near-zero (ENZ) materials have been found to have a strong optical nonlinearity, which can be enhanced through the use of cavities or nano-structuring. Here, we study the pump dependent properties of the plasmon resonance in the ENZ region in a thin layer of indium tin oxide (ITO). Exciting this mode using the Kretschmann-Raether configuration, we study reflection switching properties of a 60 nm layer close to the resonant plasmon frequency. We demonstrate a thermal switching mechanism, which results in a shift in the plasmon resonance frequency of 20 THz for a TM pump intensity of 70 GW cm−2. For degenerate pump and probe frequencies, we highlight an additional two-beam coupling contribution, not previously isolated in ENZ nonlinear optics studies, which leads to an overall pump induced change in reflection from 1% to 45%., All-optical switching is important for integrated-photonics and communication devices. Here the authors demonstrate all-optical switching of an Epsilon-Near-Zero plasmon resonance using indium tin oxide thin film.

Single-photon detector array technologies have advanced significantly in recent years. Cameras now exist that are not only sensitive to single photons but the individual pixels in the sensor provide photon time-of-arrival information the picosecond regime. Such unprecedented sensitivity and temporal resolution opens up a number of exiting new applications, such as light-in-flight imaging, looking around corners with laser echoes, and seeing through dense scattering media. I will discuss the recent developments of the camera technology and discuss our latest results. I will give details of our latest field trials, where we have been using single-photon detector array sensors to see through fog and smoke. I will also discuss our latest results for high-speed imaging in three dimensions. The latest sensor is able to capture 3D data at frame rates greater than 1000 frames per second. This technology is relevant for the analysis of rapidly changing systems where three dimensional information is necessary.

An ultra-compact 1.4mm $\times 1.4$ mm, $128 \times 120$ SPAD image sensor with a 5-wire interface is designed for time-resolved fluorescence microendoscopy. Dynamic range (DR) is extended by noiseless frame summation in SRAM attaining 126dB time resolved imaging at 15fps with 390ps gating resolution. The sensor SoC is implemented in STMicroelectronics 40nm/90nm 3D-stacked BSI CMOS process with $8 \mu \mathrm{m}$ pixels and 45% fill factor.

PQ Grass represents an allergen-specific immunotherapy for pre-seasonal treatment of patients with seasonal allergic rhinitis (or rhinoconjunctivitis) with or without mild-to-moderate bronchial asthma. It consists of a native pollen extract for 13 grass species, chemically modified with glutaraldehyde, and adsorbed to l-tyrosine in a microcrystalline form with addition of the adjuvant Monophosphoryl Lipid A (MPL® ). Previous non-clinical safety testing, including rat repeat dose toxicity in adult and juvenile animals, rat reproductive toxicity and rabbit local tolerance studies showed no safety findings of concern. A new Good Laboratory Practice compliant rat subcutaneous repeat dose toxicity study to evaluate a higher clinical dose and modified posology (once every 2 weeks for 13 weeks) showed no signs of toxicity. As seen in previous studies, relatively minor, immunostimulatory effects were seen such as reversible increased white cell count (notably neutrophils), increased globulin level (resulting in decreased A/G ratio) and increased fibrinogen as well as minor dose site reaction in the form of inflammatory cell infiltrate. These findings are likely due to the immunostimulatory nature of MPL and/or the presence of l-tyrosine within the adjuvanted vaccine. This new toxicity study with PQ Grass therefore supports longer posology with higher dose levels.

PQ Birch represents an allergen-specific immunotherapy for the treatment of birch pollinosis. It consists of native birch pollen extract chemically modified with glutaldehyde adsorbed to L-tyrosine in its microcrystalline form with addition of the adjuvant Monophosphoryl Lipid A (MPL®). A nonclinical safety testing strategy was designed based upon interpretation of current legislation and regulatory intelligence and comprised genotoxicity studies (bacterial reverse mutation and Chinese hamster ovary micronucleus assays), a rat repeat dose toxicology study and a rabbit local tolerance study. No safety findings of concern were found. Thus, no evidence of genotoxicity was found. Relatively minor, immunostimulatory effects were seen following repeated subcutaneous dosing (once every 2 weeks for 13 weeks) as reversible increased white cell count (notably neutrophils), increased globulin level (resulting in decreased albumin/globulin [A/G] ratio) and increased fibrinogen, as well as minor dose site reaction in the form of inflammatory cell infiltrate. These findings are likely due to the immunostimulatory nature of MPL® and/or the presence of L-tyrosine within the adjuvanted vaccine. Similar dose site inflammatory changes to the injected formulation were also noted in the rabbit local tolerance study.

Light Detection and Ranging (LIDAR) applications pose extremely challenging dynamic range (DR) requirements on optical time-of-flight (ToF) receivers due to laser returns affected by the inverse square law over 2-3 decades of distance, diverse target reflectivity, and high solar background [1]. Integrated CMOS SPADs have a native DR exceeding 140dB, typically extending from the noise floor of few cps to 100’s Mcps peak rate. To deliver this DR to downstream DSP, large SPAD time-resolved imaging arrays must count and time billions of single photon events per second demanding massively parallel on-chip pixel processing to achieve practical I/O power consumption and data rates. Hybrid Cu-Cu bonding offers a mass-manufacturable platform to implement these sensors by providing high-fill-factor SPADs optimised for NIR stacked on dense nanoscale digital processors [2]. Stacked sensor architectures involving pixel-level histogramming, on-chip peak detection and TDC/processor resource sharing are now being investigated [3–5].

Imaging systems with temporal resolution play a vital role in a diverse range of scientific, industrial, and consumer applications, e.g., fluorescent lifetime imaging in microscopy and time-of-flight (ToF) depth sensing in autonomous vehicles. In recent years, single-photon avalanche diode (SPAD) arrays with picosecond timing capabilities have emerged as a key technology driving these systems forward. Here we report a high-speed 3D imaging system enabled by a state-of-the-art SPAD sensor used in a hybrid imaging mode that can perform multi-event histogramming. The hybrid imaging modality alternates between photon counting and timing frames at rates exceeding 1000 frames per second, enabling guided upscaling of depth data from a native resolution of 64 × 32 to 256 × 128 . The combination of hardware and processing allows us to demonstrate high-speed ToF 3D imaging in outdoor conditions and with low latency. The results indicate potential in a range of applications where real-time, high throughput data are necessary. One such example is improving the accuracy and speed of situational awareness in autonomous systems and robotics.

Fragmentation can alter the ecology of rain forest remnants in many ways, but its long-term effects on tree communities are poorly understood. One phenomenon that has received little attention is tree regeneration in fragmented forests (Janzen 1983; Viana et al. 1997). Patterns of regeneration are important because they will ultimately determine the floristic composition of the remnant. Janzen (1983) suggested that fragments of tropical dry forest in Costa Rica are prone to invasions of weedy, generalist plant species from the surrounding modified matrix, which could progressively alter the floristic composition of remnants. Laurance (1991, 1997) proposed that fragments in some tropical regions are chronically disturbed by winds and other factors and may exhibit a general shift toward successional trees, lianas, and vines adapted for recurring disturbance. Using data collected over 13 years, we describe patterns of tree recruitment in a fragmented landscape in central Amazonia. We ask three questions: (1) Do rates of tree recruitment differ between fragmented and continuous forests? (2) Are recruitment rates influenced by fragment area, age, and proximity of forest edge? (3) Are regenerating trees in fragments biased toward successional species or against old-growth species?

Background Day-care open haemorrhoidectomy under local anaesthesia (LH) may be the most cost-effective approach to haemorrhoidectomy. This prospective randomized trial compared outcome after LH from patients' and clinical perspectives with that after day-care open haemorrhoidectomy under general anaesthesia (GH). Methods Forty-one patients with third-degree haemorrhoids were randomized to LH (19) or GH (22). Patient demographics were comparable. A single haemorrhoid was excised in 15 patients, and two and three haemorrhoids in 13 each. Independent nurse-led assessment and clinical evaluation were carried out for 6 months. Outcome measures were mean and expected pain scores at 30, 60 and 90 min, then daily for 10 days, and satisfaction scores at 10 days, 6 weeks and 6 months. Secondary outcomes were journey time within the day-surgery unit and overall cost. Results Pain was worse following LH than GH at 90 min after surgery (P = 0·028), but pain scores on reaching home were similar. Maximum pain was experienced on day 3 after LH and on day 6 after GH. From day 1 onwards, daily pain scores were lower in the LH group, and there was a significant difference on day 8 (mean (95 per cent confidence interval) 3·61 (2·74 to 4·48) for LH versus 5·29 (4·12 to 6·45) for GH; P = 0·027). Mean pain over 10 days, expectation and satisfaction scores were similar in the two groups. LH had a shorter journey time and was less expensive than GH. Conclusion LH has similar tolerance and clinical outcome to GH, and is associated with a shorter journey time and lower cost. Registration number: NCT00503269 (http://www.clinicaltrials.gov).

This article describes how the results of an audit of district nursing care plan documentation have been used to inform practice development in a community trust. The principle aim of the audit was to discover whether the evaluation of patient care was being adequately recorded in nursing care plans. To establish this, four commonly occurring areas of district nursing work were selected and an ideal assessment of care developed from the available evidence. The areas were: the management of leg ulceration, bath care, pressure area care and catheter care. Data capture forms were developed to record whether the features of an ideal assessment of these four areas of care were reflected in the written evaluation of that care. The results of the audit demonstrated that the evaluation of care was often inadequately recorded, which reflected poor written documentation of the initial nursing assessment. The implications of the findings of the audit for practice development in the four areas of care are discussed.

The electronic structure of di-t-butylchlorophosphine [(t-butyl) 2PCl] has been studied by photoemission spectroscopy (PES) and inner-shell electronic spectroscopy. The photoemission spectrum of (t-butyl) 2PCl exhibits features in good agreement with molecular orbital assignments based on modified neglect of differential overlap semiempirical calculations. The unoccupied electronic structure of (t-butyl) 2PCl has been investigated through P 2p, P 2s, Cl 2p, and C 1s core excitation spectra recorded by dipole-regime inner shell electron energy loss spectroscopy (ISEELS). The P 2p and P 2s spectra of (tbutyl) 2PCl exhibit features in common with PCl3 and P(CH3) 3, whereas the Cl 2p spectrum resembles that of PCl 3 and the C 1s spectrum resembles P(CH3) 3. Comparison of the photoemission and the ISEELS results emphasizes the local structural sensitivity of core excitation in contrast to the more extended picture of electronic structure provided by PES. q 1998 Elsevier Science B.V. All rights reserved

The molecular adsorption and desorption of nickelocene, Ni(C 5 H 5 ) 2 , on Ag(100) have been studied by both angle-resolved photoemission and thermal desorption. Photoemission results indicate that the initially adsorbed surface species closely resemble that of molecular nickelocene. The molecular axis is not along the surface normal, as determined by angle-resolved photoemission and angle-resolved thermal desorption spectroscopy. This is a different bonding orientation than that adopted by molecular ferrocene on Ag(100). The molecular nickelocene desorption energies resemble those observed for ferrocene on Ag(100) but are complicated by multiple chemisorption states and steric effects in the desorption process. Nickelocene is unusual in that the molecular orientation is seen to affect the angular dependence of molecular desoprtion.

Thin films of gadolinium, approximately 8 ML thick, have been grown on the corrugated (112) surface of molybdenum and the electronic structure has been investigated with angle-resolved photoelectron spectroscopy. The unfavorable lattice match between the ``steplike'' Mo(112) substrate and the preferred hexagonally ordered Gd film results in an incommensurate Gd structure that appears to be ordered, but strained along the direction of the corrugations. The hexagonal Gd lattice is expanded by more than 20% along the ``step'' lines of the substrate, as determined from the reduced Brillouin-zone size along the \ensuremath{\Gamma}\ensuremath{\Sigma}M high-symmetry line and low-energy electron diffraction. The induced strain substantially alters the conventional Gd 5d/6s bulk bands to exhibit a dispersion opposite to that of the relaxed Gd(0001) structure. Dislocations destroy the long-range crystallographic order in the direction orthogonal to the corrugations, which results in the localization of the bands along the \ensuremath{\Gamma}TK symmetry line. \textcopyright{} 1996 The American Physical Society.

We describe the design, construction, and calibration of Knudsen cell evaporators for the chemical vapor deposition of organic films. The evaporators can easily be constructed using equipment and materials available in most labs. We employed them to codeposit monomers for polyimide formation. The vapor deposition process of polyimide and other polymeric materials can be controlled to form ultrathin films suitable for the investigation of the interaction between the overlayer and the substrate. We describe a deposition system used to produce polyimide films from 2 nm to more than 1000 nm thick on 1‐ to 2‐cm‐diam substrates at growth rates from ∼1 nm/min to more than 10 nm/min.

Richard 0. Bierregaard Jr. is director of the Biological Dynamics of Forest Fragment Project at the National Museum of Natural History, Smithsonian Institution, Washington, DC 20560; his research focuses on avian community structure in Amazonian rainforests, particularly the responses of such communities to forest fragmentation. Thomas E. Lovejoy is the Assistant Secretary for External Affairs of the Smithsonian Institution, Washington, DC 20560. Valerie Kapos is a research associate in the Department of Botany, University of Cambridge, Cambridge CB2 3EA, United Kingdom and at the University of North Wales; her research is on water and nutrient relations and phenology of tropical deciduous trees and edge effects on environment and plant responses. Angelo Augusto dos Santos is the coordinator for international cooperation at Brazil's National Institute for Amazonian Research (INPA) and the Brazilian co-principal investigator of BDFFP at the National Museum of Natural History, Smithsonian Institution, Washington, DC 20560; his research focuses on the structure and ecology of tropical rainforest fragments. Roger W. Hutchings is the field director of BDFFP, Ecologia/V-8, INPA, C.P. 478, 69.011 Manaus, AM, Brazil; his research interests include butterflies in tropical forest fragments and adjacent continuous forest, botanical ecology, and general conservation biology of tropical rainforests. A mosaic of small

We will illustrate how atom beam scattering (ABS) can be used to study the growth and ordering of adsorption of Hg on Cu(001). At low coverage (less than 2% of a monolayer), we obtain that the scattering cross section of He with (adsorbed) Hg is about 50 A2. We find that mercury forms two stable phases on Cu(001) in the temperature range between 200 and 330 K, a c(2×2) and a high density c(4×4) phase. From ABS diffraction data, we can deduce the corrugation of the surface electron charge density of the mercury layer in the two ordered phases. From the analysis of our data, we obtain a Debye temperature for the Hg overlayer of about 115 K. We will report preliminary calculations on the adsorption energy of Hg on Cu(001) and on the interaction of He with a Hg preplated Cu(001) surface.

We have investigated the adsorption of mercury overlayers on Cu(100) by atom beam scattering, low energy electron diffraction and angle resolved photoemission. From our data we have calculated the isosteric heats in the adsorbed Hg layer on Cu(100) and compared these with results obtained for mercury on Fe(100), W(100) and Ni(100). We observe changes in the isosteric heat of adsorption that can be associated with the ordering of a c(2 × 2) Hg overlayer phase and the transition from a c(2 × 2) overlayer to a c(4 × 4) overlayer. The isosteric heat of adsorption is 0.50 ± 0.07 eV/atom (48 ± 7 kJ/mol) at zero coverage and reaches a maximum of 0.73 ± 0.04 eV/atom (70 ± 4 kJ/mol). From a combination of ABS and LEED, the structures of the two equilibrium ordered phases of Hg on Cu(100) have been identified, as well as the structures of several non-equilibrium phases.

Background Our knowledge of allergen structure and function continues to rise and new scientific data on the homology and cross-reactivity of allergen sources should be considered to extend the work of Lorenz et al., 2009 (Int Arch Allergy Immunol. 148(1):1–1, 2009) and the concept of homologous groups. In addition to this, sophisticated techniques such as mass spectrometry (MS) are increasingly utilised to better characterise the complex mix and nature of allergen extracts. Methods Homology models were used of Fag s 1 (Beech) and Cyn d 1 (Bermuda grass) and compared with template crystal structures of Bet v 1 and Phl p 1 from the ‘exemplar’ species of Birch and Timothy grass, respectively. ELISA experiments were performed to assess cross-reactivity of Beech (tree) and Bermuda (grass) extracts to rabbit sera raised to either “3-Tree” (Birch, Alder and Hazel) extract or “Grass” (12-grass mix extract), respectively. The comparability of biochemical stability of different allergen sources was assessed through statistical methods for a range of tree and grass species. Results Allergen cross-reactivity and/or structural homology have been described providing justification for inclusion of Beech within the Birch homologous tree group. Data from Bermuda grass (Cyn d 1) provides further justification for the inclusion of this species into the homologous group of the sweet grasses. However, further characterisation of relevant allergens from Bermuda grass and, in particular, comparison of cross-reactive patterns between subjects specifically in areas with high abundance of both Pooideae and Chloridoideae is sought. Conclusion MS allows the possibility to identify individual proteins or allergens from complex mixes by mass and/or sequence, and this has been extensively applied to the allergen field. New data on the homology, cross-reactivity and biological parameters of allergen sources have been considered to extend the work of Lorenz et al., 2009 in the context of tree and grass species. The concept of homologous groups is certainly dynamic allowing the flexibility and potential in streamlining quality parameters, such as stability profiles, due to extrapolation of exemplar data to a wider range of allergens. Electronic supplementary material The online version of this article (doi:10.1186/s40413-015-0069-9) contains supplementary material, which is available to authorized users.

A switched mode power supply (SMPS) with full digital control has many advantages over analog or mixed-signal implementation. This paper presents a digital controlled SMPS consisting of an AC-DC power factor correction converter and a phase-shifted full-bridge DC-DC converter. Digital algorithm of PFC control, system design of digital PFC and PSFB (phase shifted full bridge) part, PWM strategy for phase-shifted control are discussed. A 500 W prototype has been built and tested under different conditions

We have deposited CoxNiy‐C films with a variety of compositions to verify dependence of the saturation magnetization on the composition. These experiments suggest that we can produce CoxNiy‐C films with a variety of magnetic properties. The CoxNiy‐C films were fabricated by ultraviolet decomposition of cobaltocene and nickelocene. We demonstrated that the photolytic decomposition of these metallocenes produces cyclopentadienyl (C5H5) species, consistent with recent studies of the energetics of the ligand metal bonds.

We used atom beam scattering (ABS), LEED and angle-resolved photo-electron spectroscopy (ARPES) to study bilayer films of Hg on Cu(001). In the surface temperature range of 180 to 330 K, the first Hg layer forms two ordered phases, a c(2×2) (with coverage=0.5 of Cu(001)) and a high density (partially commensurate) c(4×4) (coverage=0.62 ). ARPES data show that there is little or no dispersion of the 5d band of Hg. ABS data show that this layer is not flat, with in-registry Hg atoms lying about 0.15 below the not-in-registry Hg atoms. From ABS we find that the second layer forms a completely registered c(4times;4) phase. From ARPES we obtain that the second layer has an electronic structure, particularly the 5d levels, characteristic of bulk mercury.Preliminary results of calculations of the structure of the bilayer are given.

For the first time an ionic liquid is observed to be appreciably miscible in dense CO2, up to about 7 mass%. The solubility in CO2 is more than one order of magnitude higher than for alkanes of similar carbon number. The investigated P–T phase behavior of four isopleths for the ionic liquid trihexyltetradecylphosphonium chloride in CO2 shows a concentration independence of the isopleths for the investigated compositions similar to the known phase behavior of organic compounds such as adamantane, octacosane and squalane in supercritical CO2 at high pressures. Overall, the results demonstrate that a single-phased ionic liquid–CO2 solvent system for chemical synthesis is conceivable.

We have measured the molecular orientation and bonding of adsorbed ferrocene on Ag(100) and Cu(100) using angle-resolved photoemission spectroscopy (ARPES). The results for molecular adsorption on Ag(100) are complemented by high-resolution electron energy loss spectroscopy (HREELS) measurments and ab initio calculations for the ferrocene vibrational modes. The measurements indicate that ferrocene adsorbs on Ag(100) with the molecular axis perpendicular to the surface. In contrast, as indicated using ARPES and scanning tunneling microscopy, ferrocene adsorbed on the Cu(100) surface is oriented with the molecular axis parallel with the surface. Model calculations allow us to assign all of the observed vibrational modes for the weakly bound molecular ferrocene on Ag(100)−both dipole and impact scattering modes have been observed.

Lunar and solar atmospheric tidal oscillations have been determined with satisfactory accuracy from 17 years 11 months of mean sea-level barometric pressure observations taken at Nandi, Fiji. In many respects, the results are consistent with previous tidal determinations in the south-west Pacific region, although these are few and widely scattered. However, the mean annual amplitude of the lunar tide at Nandi, as determined in this study, ∼88 μb, is much greater than might have been expected from currently available global amplitude maps. Nevertheless, the probable correctness of this result has been confirmed by the analysis of nearly 6 years of similar data from Nausori (∼130 km E.S.E. of Nandi), which yielded a mean annual lunar amplitude of ∼88 μb, compared with a Nandi amplitude of ∼83 μb for a closely corresponding period.