826 research outputs found
Using modern methods for missing data analysis with the social relations model: A bridge to social network analysis
Femoral lengthening in young patients : an evidence-based comparison between motorized lengthening nails and external fixation
BACKGROUND
Femoral lengthening is a procedure of great importance in the treatment of congenital and acquired limb deficiencies. Technological advances have led to the latest designs of fully implantable motorized intramedullary lengthening nails. The use of these nails has increased over the last few years.
AIM
To review and critically appraise the literature comparing the outcome of femoral lengthening in children using intramedullary motorized lengthening nails to external fixation.
METHODS
Electronic databases (MEDLINE, CINAHL, EMBASE, Cochrane) were systematically searched in November 2019 for studies comparing the outcome of femoral lengthening in children using magnetic lengthening nails and external fixation. The outcomes included amount of gained length, healing index, complications and patient reported outcomes.
RESULTS
Of the 452 identified studies, only two (retrospective and non-randomized) met the inclusion criteria. A total of 91 femora were included. In both studies, the age of patients treated with nails ranged from 15 to 21 years compared to 9 to 15 years for patients in the external fixation group. Both devices achieved the target length. Prevalence of adverse events was less in the nail (60%-73%) than in the external fixation (81%-100%) group. None of the studies presented patient reported outcomes.
CONCLUSION
The clinical effectiveness of motorized nails is equivalent or superior to external fixation for femoral lengthening in young patients. The available literature is limited and does not provide evidence on patient quality of life or cost effectiveness of the interventions
Quality of life of children during distraction osteogenesis : a comparison between intramedullary magnetic lengthening nails and external fixators
Background
Distraction osteogenesis is a very demanding process. For decades, external fixation was the only reliable option for gradual deformity correction. Recently, intramedullary magnetic nails have gained popularity. This research aimed to assess the quality of life in children during gradual deformity correction using intramedullary lengthening nails compared to external fixation.
Method
Prospective analysis included children who had gradual lower limb deformity correction between 2017 and 2019. Group A included children who had magnetic lengthening nails; patients in group B had external fixation devices. Child health utility 9D (CHU- 9D) and EuroQol 5D youth (EQ- 5D-Y) were used to measure the quality of life at fixed points during the distraction osteogenesis process. The results were used to calculate the utility at each milestone and the overall quality of life adjusted years (QALYs).
Results
Thirty-four children were recruited, group A had 16 patients, whilst group B had 18 patients. The average ages were 16.0 years and 14.7 years for groups A and B, respectively. Group A patients reported significantly better utility compared to group B. This was observed during all stages of treatment (P = 0.00016). QALYs were better for group A (0.44) compared to group B (0.34) (P < 0.0001).
Conclusion
The quality of life was generally better in group A compared to group B. In most patients, the health utility progressively improved throughout treatment. In the same way, QALYs were better with the lengthening nails compared to external fixators. The magnetic lengthening devices (PRECICE nails) which were used in this research were recently relabelled to restrict their applications in children; this study was conducted before these restrictions
Мультипарадигмальний підхід до аналізу феномену нігілізму
У статті розглянуто нігілізм як неоднозначне й поліморфне поняття. Досліджено різні підходи до
тлумачення та розв’язання питань, пов’язаних із нігілізмом. Розкрито людиномірність нігілізму в контексті
відстеження варіативного смислового навантаження феномену. Встановлено, що нігілізм потрібно
позиціонувати як спосіб пробудження людського духу, заперечення деструктивного конформізму й
відсутності опору (пасивний песимізм).В статье рассмотрен нигилизм как неоднозначное и полиморфное понятие. Исследованы различные подходы
к толкованию и решению вопросов, связанных с нигилизмом. Раскрыта человекомерность нигилизма
в контексте отслеживания вариативной смысловой нагрузки феномена. Установлено, что нигилизм нужно
позиционировать как способ пробуждения человеческого духа, отрицание деструктивного конформизма и
отсутствия сопротивления (пассивный пессимизм).Nihilism is considered as ambiguous and polymorphic concept. Different approaches to the interpretation and solution of
issues associated with nihilism are investigated. Human measurement of nihilism in the context of tracking meaning of
varied semantic capacity of the phenomenon is revealed. It is determined that nihilism must be positioned as a way of
awakening of the human spirit, denial of destructive conformism and absence of resistance (passive pessimism)
Rotating Resonator-Oscillator Experiments to Test Lorentz Invariance in Electrodynamics
In this work we outline the two most commonly used test theories (RMS and
SME) for testing Local Lorentz Invariance (LLI) of the photon. Then we develop
the general framework of applying these test theories to resonator experiments
with an emphasis on rotating experiments in the laboratory. We compare the
inherent sensitivity factors of common experiments and propose some new
configurations. Finally we apply the test theories to the rotating cryogenic
experiment at the University of Western Australia, which recently set new
limits in both the RMS and SME frameworks [hep-ph/0506074].Comment: Submitted to Lecture Notes in Physics, 36 pages, minor modifications,
updated list of reference
How much does paediatric femoral lengthening cost? A cost comparison between magnetic lengthening nails and external fixators
Aim: Motorised intramedullary lengthening nails are considered more expensive than external fixators for limb lengthening. This research aims to compare the cost of femoral lengthening in children using the PRECICE magnetic lengthening nail with external fixation. Methods: Retrospective analysis of 50 children who underwent femoral lengthening. One group included patients who were treated with PRECICE lengthening nails, the other group included patients who had lengthening with external fixation. Each group included 25 patients aged between 11 and 17 years. The patients in both groups were matched for age. Cost analysis was performed following micro-costing and analysis of the used resources during the different phases of the treatments. Results: Each group's mean patient age was 14.7 years. Lengthening nails were associated with longer operative times compared with external fixators, both for implantation and removal surgery (p-values of 0.007 and < 0.0001, respectively). Length of stay following the implantation surgery, frequency of radiographs and frequency of outpatient department appointments were all lower with lengthening nails. The overall cost of lengthening nails was £1393 more than external fixators, however, this difference was not statistically significant (p-value = 0.088). Conclusion: The difference in the mean costs between femoral lengthening with lengthening nails versus external fixators was not statistically significant. Further research to review the effectiveness of the devices and the quality of life during the lengthening process is crucial for robust health economic evaluation
The Bethe-Ansatz for N=4 Super Yang-Mills
We derive the one loop mixing matrix for anomalous dimensions in N=4 Super
Yang-Mills. We show that this matrix can be identified with the Hamiltonian of
an integrable SO(6) spin chain with vector sites. We then use the Bethe ansatz
to find a recipe for computing anomalous dimensions for a wide range of
operators. We give exact results for BMN operators with two impurities and
results up to and including first order 1/J corrections for BMN operators with
many impurities. We then use a result of Reshetikhin's to find the exact
one-loop anomalous dimension for an SO(6) singlet in the limit of large bare
dimension. We also show that this last anomalous dimension is proportional to
the square root of the string level in the weak coupling limit.Comment: 35 pages, 3 figures, LaTeX; v2 references added, typos corrected,
\Lambda fixed; v3 expanded discussion of higher loops in conclusion, matches
published versio
Accounting for the impact of conservation on human well-being
Conservationists are increasingly engaging with the concept of human well-being to improve the design and evaluation of their interventions. Since the convening of the influential Sarkozy Commission in 2009, development researchers have been refining conceptualizations and frameworks to understand and measure human well-being and are starting to converge on a common understanding of how best to do this. In conservation, the term human well-being is in widespread use, but there is a need for guidance on operationalizing it to measure the impacts of conservation interventions on people. We present a framework for understanding human well-being, which could be particularly useful in conservation. The framework includes 3 conditions; meeting needs, pursuing goals, and experiencing a satisfactory quality of life. We outline some of the complexities involved in evaluating the well-being effects of conservation interventions, with the understanding that well-being varies between people and over time and with the priorities of the evaluator. Key challenges for research into the well-being impacts of conservation interventions include the need to build up a collection of case studies so as to draw out generalizable lessons; harness the potential of modern technology to support well-being research; and contextualize evaluations of conservation impacts on well-being spatially and temporally within the wider landscape of social change. Pathways through the smog of confusion around the term well-being exist, and existing frameworks such as the Well-being in Developing Countries approach can help conservationists negotiate the challenges of operationalizing the concept. Conservationists have the opportunity to benefit from the recent flurry of research in the development field so as to carry out more nuanced and locally relevant evaluations of the effects of their interventions on human well-being
Recovery of NMDA receptor currents from MK-801 blockade is accelerated by Mg2+ and memantine under conditions of agonist exposure
AbstractMK-801 is a use-dependent NMDA receptor open channel blocker with a very slow off-rate. These properties can be exploited to ‘pre-block’ a population of NMDARs, such as synaptic ones, enabling the selective activation of a different population, such as extrasynaptic NMDARs. However, the usefulness of this approach is dependent on the stability of MK-801 blockade after washout. We have revisited this issue, and confirm that recovery of NMDAR currents from MK-801 blockade is enhanced by channel opening by NMDA, and find that it is further increased when Mg2+ is also present. In the presence of Mg2+, 50% recovery from MK-801 blockade is achieved after 10′ of 100 μM NMDA, or 30′ of 15 μM NMDA exposure. In Mg2+-free medium, NMDA-induced MK-801 dissociation was found to be much slower. Memantine, another PCP-site antagonist, could substitute for Mg2+ in accelerating the unblock of MK-801 in the presence of NMDA. This suggests a model whereby, upon dissociation from its binding site in the pore, MK-801 is able to re-bind in a process antagonized by Mg2+ or another PCP-site antagonist. Finally we show that even when all NMDARs are pre-blocked by MK-801, incubation of neurons with 100 μM NMDA in the presence of Mg2+ for 2.5 h triggers sufficient unblocking to kill >80% of neurons. We conclude that while synaptic MK-801 ‘pre-block’ protocols are useful for pharmacologically assessing synaptic vs. extrasynaptic contributions to NMDAR currents, or studying short-term effects, it is problematic to use this technique to attempt to study the effects of long-term selective extrasynaptic NMDAR activation.This article is part of the Special Issue entitled ‘Glutamate Receptor-Dependent Synaptic Plasticity’
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