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Bringing high-grade arteriovenous malformations under control: clinical outcomes following multimodality treatment in children.
OBJECTIVE:Brain arteriovenous malformations (AVMs) consist of dysplastic blood vessels with direct arteriovenous shunts that can hemorrhage spontaneously. In children, a higher lifetime hemorrhage risk must be balanced with treatment-related morbidity. The authors describe a collaborative, multimodal strategy resulting in effective and safe treatment of pediatric AVMs. METHODS:A retrospective analysis of a prospectively maintained database was performed in children with treated and nontreated pediatric AVMs at the University of California, San Francisco, from 1998 to 2017. Inclusion criteria were age ≤ 18 years at time of diagnosis and an AVM confirmed by a catheter angiogram. RESULTS:The authors evaluated 189 pediatric patients with AVMs over the study period, including 119 ruptured (63%) and 70 unruptured (37%) AVMs. The mean age at diagnosis was 11.6 ± 4.3 years. With respect to Spetzler-Martin (SM) grade, there were 38 (20.1%) grade I, 40 (21.2%) grade II, 62 (32.8%) grade III, 40 (21.2%) grade IV, and 9 (4.8%) grade V lesions. Six patients were managed conservatively, and 183 patients underwent treatment, including 120 resections, 82 stereotactic radiosurgery (SRS), and 37 endovascular embolizations. Forty-four of 49 (89.8%) high-grade AVMs (SM grade IV or V) were treated. Multiple treatment modalities were used in 29.5% of low-grade and 27.3% of high-grade AVMs. Complete angiographic obliteration was obtained in 73.4% of low-grade lesions (SM grade I-III) and in 45.2% of high-grade lesions. A periprocedural stroke occurred in a single patient (0.5%), and there was 1 treatment-related death. The mean clinical follow-up for the cohort was 4.1 ± 4.6 years, and 96.6% and 84.3% of patients neurologically improved or remained unchanged in the ruptured and unruptured AVM groups following treatment, respectively. There were 16 bleeding events following initiation of AVM treatment (annual rate: 0.02 events per person-year). CONCLUSIONS:Coordinated multidisciplinary evaluation and individualized planning can result in safe and effective treatment of children with AVMs. In particular, it is possible to treat the majority of high-grade AVMs with an acceptable safety profile. Judicious use of multimodality therapy should be limited to appropriately selected patients after thorough team-based discussions to avoid additive morbidity. Future multicenter studies are required to better design predictive models to aid with patient selection for multimodal pediatric care, especially with high-grade AVMs
Higgs Physics with a gamma gamma Collider Based on CLIC 1
We present the machine parameters and physics capabilities of the CLIC Higgs
Experiment (CLICHE), a low-energy collider based on CLIC 1, the
demonstration project for the higher-energy two-beam accelerator CLIC. CLICHE
is conceived as a factory capable of producing around 20,000 light Higgs bosons
per year. We discuss the requirements for the CLIC 1 beams and a laser
backscattering system capable of producing a total (peak)
luminosity of cms with GeV. We show how CLICHE could be used to measure accurately
the mass, , and decays of a light Higgs boson.
We illustrate how these measurements may distinguish between the Standard Model
Higgs boson and those in supersymmetric and more general two-Higgs-doublet
models, complementing the measurements to be made with other accelerators. We
also comment on other prospects in and physics with
CLICHE.Comment: 34 pages, 20 figures, Latex. submitted to Eur. Phys. Jou
CLIC Beam Delivery System
We review the present design for the CLIC beam delivery system as configured for 3 TeV and for 500 GeV, describe some recent developments (including the combined effect of solenoid, crab cavity, and crossing angle), highlight open questions, and outline future studies
Long-Term Warming Alters Carbohydrate Degradation Potential in Temperate Forest Soils
As Earth\u27s climate warms, soil carbon pools and the microbial communities that process them may change, altering the way in which carbon is recycled in soil. In this study, we used a combination of metagenomics and bacterial cultivation to evaluate the hypothesis that experimentally raising soil temperatures by 5°C for 5, 8, or 20 years increased the potential for temperate forest soil microbial communities to degrade carbohydrates. Warming decreased the proportion of carbohydrate-degrading genes in the organic horizon derived from eukaryotes and increased the fraction of genes in the mineral soil associated with Actinobacteria in all studies. Genes associated with carbohydrate degradation increased in the organic horizon after 5 years of warming but had decreased in the organic horizon after warming the soil continuously for 20 years. However, a greater proportion of the 295 bacteria from 6 phyla (10 classes, 14 orders, and 34 families) isolated from heated plots in the 20-year experiment were able to depolymerize cellulose and xylan than bacterial isolates from control soils. Together, these findings indicate that the enrichment of bacteria capable of degrading carbohydrates could be important for accelerated carbon cycling in a warmer world
Design Status of the CLIC 3-TeV Beam Delivery System and Damping Rings
We describe the present design status of beam delivery and damping rings for CLIC at 3 TeV cm energy, and outline our future plans. The beam delivery system comprises collimation, final focus and post-IP exit line. Critical design aspects include halo collimation, machine protection, beam removal, and thermal stability analysis. In order to attain the design spot size at the collision point, the damping rings must provide beams of extremely small emittances. In this paper, we focus on collimation and spent beam
Exact Three Dimensional Casimir Force Amplitude, -function and Binder's Cumulant Ratio: Spherical Model Results
The three dimensional mean spherical model on a hypercubic lattice with a
film geometry under periodic boundary conditions is
considered in the presence of an external magnetic field . The universal
Casimir amplitude and the Binder's cumulant ratio are calculated
exactly and found to be and
A discussion on the relations
between the finite temperature -function, usually defined for quantum
systems, and the excess free energy (due to the finite-size contributions to
the free energy of the system) scaling function is presented. It is
demonstrated that the -function of the model equals 4/5 at the bulk critical
temperature . It is analytically shown that the excess free energy is a
monotonically increasing function of the temperature and of the magnetic
field in the vicinity of This property is supposed to hold for any
classical -dimensional model with a film geometry under periodic
boundary conditions when . An analytical evidence is also presented to
confirm that the Casimir force in the system is negative both below and in the
vicinity of the bulk critical temperature Comment: 12 pages revtex, one eps figure, submitted to Phys. Rev E A set of
references added with the text needed to incorporate them. Small changes in
the title and in the abstrac
Mesons on a transverse lattice
The meson eigenstates of the light-cone Hamiltonian in a coarse transverse
lattice gauge theory are investigated. Building upon previous work in pure
gauge theory, the Hamiltonian and its Fock space are expanded in powers of
dynamical fields. In the leading approximation, the couplings appearing in the
Hamiltonian are renormalised by demanding restoration of space-time symmetries
broken by the cut-off. Additional requirements from chiral symmetry are
discussed and difficulties in imposing them from first principles in the
leading approximation are noted. A phenomenological calculation is then
performed, in which chiral symmetry in spontaneously broken form is modelled by
imposing the physical pion-rho mass splitting as a constraint. The light-cone
wavefunctions of the resulting Hamiltonian are used to compute decay constants,
form factors and quark momentum and spin distributions for the pion and rho
mesons. Extensions beyond leading order, and the implications for first
principles calculations, are briefly discussed.Comment: 31 pages, 7 figure
Photon-Photon and Electron-Photon Colliders with Energies Below a TeV
We investigate the potential for detecting and studying Higgs bosons in and collisions at future linear colliders with energies below a TeV. Our study incorporates realistic spectra based on available laser technology, and NLC and CLIC acceleration techniques. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson based on a devoted low energy machine with GeV; b) the heavy MSSM Higgs bosons; and c) charged Higgs bosons in collisions.We investigate the potential for detecting and studying Higgs bosons in and collisions at future linear colliders with energies below a TeV. Our study incorporates realistic spectra based on available laser technology, and NLC and CLIC acceleration techniques. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson based on a devoted low energy machine with GeV; b) the heavy MSSM Higgs bosons; and c) charged Higgs bosons in collisions
Prospective Environmental Life Cycle Assessment of Nanosilver T-Shirts
A cradle-to-grave life cycle assessment (LCA) is performed to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For nanosilver production and textile incorporation, we investigate two processes: flame spray pyrolysis (FSP) and plasma polymerization with silver co-sputtering (PlaSpu). Prospective environmental impacts due to increased nanosilver T-shirt commercialization are estimated with six scenarios. Results show significant differences in environmental burdens between nanoparticle production technologies: The "cradle-to-gate" climate footprint of the production of a nanosilver T-shirt is 2.70 kg of CO2-equiv (FSP) and 7.67-166 kg of CO2-equiv (PlaSpu, varying maturity stages). Production of conventional T-shirts with and without the biocide triclosan has emissions of 2.55 kg of CO2-equiv (contribution from triclosan insignificant). Consumer behavior considerably affects the environmental impacts during the use phase. Lower washing frequencies can compensate for the increased climate footprint of FSP nanosilver T-shirt production. The toxic releases from washing and disposal in the life cycle of T-shirts appear to be of minor relevance. By contrast, the production phase may be rather significant due to toxic silver emissions at the mining site if high silver quantities are require
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