Developing effective therapeutic relationships with children, young people and their families

It is imperative that nurses caring for children, young people and their families develop and maintain effective, trusting and collaborative therapeutic relationships that sit within the scope of professional boundaries. This relationship is the nurse’s responsibility and should be positive and mutually acceptable to all stakeholders. A unique challenge for children’s nurses is to address and prioritise the child’s care needs, while meeting the needs of, and empowering, the family. The 6Cs – care, compassion, competence, communication, courage, commitment – should underpin care and enable nurses to overcome challenges such as time pressures, acute situations or disturbed family expectation. Confidentiality and safeguarding should always be observed

Uplift histories of Africa and Australia from linear inverse modeling of drainage inventories

We describe and apply a linear inverse model which calculates spatial and temporal patterns of uplift rate by minimizing the misfit between inventories of observed and predicted longitudinal river profiles. Our approach builds upon a more general, non-linear, optimization model, which suggests that shapes of river profiles are dominantly controlled by upstream advec- tion of kinematic waves of incision produced by spatial and temporal changes in regional uplift rate. Here, we use the method of characteristics to solve a version of this problem. A damped, non-negative, least squares approach is developed that permits river profiles to be inverted as a function of up- lift rate. An important benefit of a linearized treatment is low computational cost. We have tested our algorithm by inverting 957 river profiles from both Africa and Australia. For each continent, the drainage network was constructed from a digital elevation model. The fidelity of river profiles extracted from this network was carefully checked using satellite imagery. River profiles were inverted many times to systematically investigate the trade-off between model misfit and smoothness. Spatial and temporal patterns of both uplift rate and cumulative uplift were calibrated using independent geologic and geophys- ical observations. Uplift patterns suggest that the topography of Africa and Australia grew in Cenozoic times. Inverse modeling of large inventories of river profiles demonstrates that drainage networks contain coherent signals that record the regional growth of elevation.This is the final version. It first appeared at http://onlinelibrary.wiley.com/wol1/doi/10.1002/2014JF003297/abstract

Manipulating photon coherence to enhance the security of distributed phase reference quantum key distribution

Distributed-phase-reference (DPR) systems were introduced as a method of decreasing the complexity of quantum key distribution systems for practical use. However, their information-theoretic security has only been proven when the added requirement of block-wise phase randomisation is met. Realisation of this with a conventional approach would result in a cumbersome transmitter, removing any practical advantage held by DPR systems. Here we solve this problem using a light source that allows the coherence between pulses to be controlled on a pulse-by-pulse basis without the need for additional bulky components. The system is modulator-free, does not require a complex receiver, and features an excellent stability without an active stabilisation mechanism. We achieve megabit per second key rates that are almost three times higher than those obtained with the standard Bennet-Brassard 1984 (BB84) protocol

North Atlantic ocean circulation and abrupt climate change during the last glaciation.

The most recent ice age was characterized by rapid and hemispherically asynchronous climate oscillations, whose origin remains unresolved. Variations in oceanic meridional heat transport may contribute to these repeated climate changes, which were most pronounced during marine isotope stage 3, the glacial interval 25 thousand to 60 thousand years ago. We examined climate and ocean circulation proxies throughout this interval at high resolution in a deep North Atlantic sediment core, combining the kinematic tracer protactinium/thorium (Pa/Th) with the deep water-mass tracer, epibenthic δ(13)C. These indicators suggest reduced Atlantic overturning circulation during every cool northern stadial, with the greatest reductions during episodic Hudson Strait iceberg discharges, while sharp northern warming followed reinvigorated overturning. These results provide direct evidence for the ocean's persistent, central role in abrupt glacial climate change

Directly phase-modulated light source

The art of imparting information onto a light wave by optical signal modulation is fundamental to all forms of optical communication. Among many schemes, direct modulation of laser diodes stands out as a simple, robust, and cost-effective method. However, the simultaneous changes in intensity, frequency, and phase have prevented its application in the field of secure quantum communication. Here, we propose and experimentally demonstrate a directly phase-modulated light source which overcomes the main disadvantages associated with direct modulation and is suitable for diverse applications such as coherent communications and quantum cryptography. The source separates the tasks of phase preparation and pulse generation between a pair of semiconductor lasers leading to very pure phase states. Moreover, the cavity-enhanced electro-optic effect enables the first example of subvolt half-wave phase modulation at high signal rates. The source is compact, stable, and versatile, and we show its potential to become the standard transmitter for future quantum communication networks based on attenuated laser pulses

Intra-arterial nitroglycerin as directed acute treatment in experimental ischemic stroke

BACKGROUND: Nitroglycerin (also known as glyceryl trinitrate (GTN)), a vasodilator best known for treatment of ischemic heart disease, has also been investigated for its potential therapeutic benefit in ischemic stroke. The completed Efficacy of Nitric Oxide in Stroke trial suggested that GTN has therapeutic benefit with acute (within 6 hours) transdermal systemic sustained release therapy. OBJECTIVE: To examine an alternative use of GTN as an acute therapy for ischemic stroke following successful recanalization. METHODS: We administered GTN IA following transient middle cerebral artery occlusion in mice. Because no standard dose of GTN is available following emergent large vessel occlusion, we performed a dose-response (3.12, 6.25, 12.5, and 25 µg/µL) analysis. Next, we looked at blood perfusion (flow) through the middle cerebral artery using laser Doppler flowmetry. Functional outcomes, including forced motor movement rotor rod, were assessed in the 3.12, 6.25, and 12.5 µg/µL groups. Histological analysis was performed using cresyl violet for infarct volume, and glial fibrillary activating protein (GFAP) and NeuN immunohistochemistry for astrocyte activation and mature neuron survival, respectively. RESULTS: Overall, we found that acute post-stroke IA GTN had little effect on vessel dilatation after 15 min. Functional analysis showed a significant difference between GTN (3.12 and 6.25 µg/µL) and control at post-stroke day 1. Histological measures showed a significant reduction in infarct volume and GFAP immunoreactivity and a significant increase in NeuN. CONCLUSIONS: These results demonstrate that acute IA GTN is neuroprotective in experimental ischemic stroke and warrants further study as a potentially new stroke therapy

Best-Practice Criteria for Practical Security of Self-Differencing Avalanche Photodiode Detectors in Quantum Key Distribution

Fast gated avalanche photodiodes (APDs) are the most commonly used single photon detectors for high bit rate quantum key distribution (QKD). Their robustness against external attacks is crucial to the overall security of a QKD system or even an entire QKD network. Here, we investigate the behavior of a gigahertz-gated, self-differencing InGaAs APD under strong illumination, a tactic Eve often uses to bring detectors under her control. Our experiment and modelling reveal that the negative feedback by the photocurrent safeguards the detector from being blinded through reducing its avalanche probability and/or strengthening the capacitive response. Based on this finding, we propose a set of best-practice criteria for designing and operating fast-gated APD detectors to ensure their practical security in QKD

Intensity modulation as a preemptive measure against blinding of single-photon detectors based on self-differencing cancellation

Quantum key distribution is rising as an important cryptographic primitive for protecting the communication infrastructure in the digital era. However, its implementation security is often weakened by components whose behavior deviates from what is expected. Here we analyze the response of a self-differencing avalanche photodiode, a key enabler for high speed quantum key distribution, to intense light shone from a continuous-wave laser. Under incorrect settings, the cancellation entailed by the self-differencing circuitry can make the detector insensitive to single photons. However, we experimentally demonstrate that even in such cases intensity modulation can be used as an effective measure to restore the detector's expected response to the input light.A.K.-S. gratefully acknowledges financial support from Toshiba Research Europe Ltd. and the Engineering and Physical Sciences Research Council (EPSRC) through an Industrial CASE studentship Grant No. NMZE\187 (RG84410)

Best-Practice Criteria for Practical Security of Self-Differencing Avalanche Photodiode Detectors in Quantum Key Distribution

Fast-gated avalanche photodiodes (APDs) are the most commonly used single photon detectors for high-bit-rate quantum key distribution (QKD). Their robustness against external attacks is crucial to the overall security of a QKD system, or even an entire QKD network. We investigate the behavior of a gigahertz-gated, self-differencing (In,Ga)As APD under strong illumination, a tactic Eve often uses to bring detectors under her control. Our experiment and modeling reveal that the negative feedback by the photocurrent safeguards the detector from being blinded through reducing its avalanche probability and/or strengthening the capacitive response. Based on this finding, we propose a set of best-practice criteria for designing and operating fast-gated APD detectors to ensure their practical security in QKD