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This is a response to the paper published by S. A. Kadam, H. Li, R. F. Wormsbacher, A. Travert, Chem. Eur. J. 2018 , 24, 5489. Key consistencies between our reported results and those reported in this work are also highlighted.
The BFSS matrix model relates flat space M-theory to a large N limit of matrix quantum mechanics describing N non-relativistic D0-branes. M-theory, being a theory of gravity in flat space, has a rich infrared structure that includes various soft theorems and an infinite set of conserved charges associated to asymptotic symmetries. In this work, we ask: to what extent is this infrared structure present in BFSS? We find that all the salient features concerning the infrared structure of M-theory carry over naturally to the quantum mechanics dual. Moreover, we demonstrate that the dual statement of the soft graviton theorem in the matrix model implies that D0-brane scattering amplitudes in BFSS enjoy the full 11d Lorentz symmetry of M-theory, a claim which has been long anticipated. We also offer several first-principle consistency checks for our findings, including a computation of the soft theorem which does not presuppose the BFSS duality and a non-trivial match between several known symmetries of M-theory and BFSS that appear naturally in this formalism. These calculations give non-perturbative evidence in support of the BFSS duality as a model of flat space holography.
Infrared divergences in perturbative gravitational scattering amplitudes have been recently argued to be governed by the two-point function of the supertranslation Goldstone mode on the celestial sphere. We show that the form of this celestial two-point function simply derives from an effective action that also controls infrared divergences in the symplectic structure of General Relativity with asymptotically flat boundary conditions. This effective action finds its natural place in a path integral formulation of a celestial conformal field theory, as we illustrate by re-deriving the infrared soft factors in terms of celestial correlators. Our analysis relies on a well-posed action principle close to spatial infinity introduced by Compère and Dehouck.
We study an attractive scenario, “Sleptonic SUSY”, which reconciles the 125 GeV Higgs scalar and the non-observation of superpartners thus far with potentially pivotal roles for slepton phenomenology: providing viable ongoing targets for LHC discovery, incorporating a co-annihilation partner for detectable thermal relic dark matter, and capable of mediating the potential muon g – 2 anomaly. This is accomplished by a modestly hierarchical spectrum, with sub-TeV sleptons and electroweakinos and with multi-TeV masses for the other new states. We study new elements in the UV MSSM realization of Sleptonic SUSY based on higher-dimensional sequestering and the synergy between the resulting gaugino-mediation, hypercharge D-term mediation and Higgs-mediation of SUSY-breaking, so as to more fully capture the range of possibilities. This framework stands out by harmoniously solving the flavor, CP and μ – Bμ problems of the supersymmetric paradigm. We discuss its extension to orbifold GUTs, including gauge-coupling and b-tau unification. We also develop a non-minimal model with extra Higgs fields, in which the electroweak vacuum is more readily cosmologically stable against decay to a charge-breaking vacuum, allowing a broader range of sleptonic spectra than in the MSSM alone. We survey the rich set of signals possible at the LHC and future colliders, covering both R-parity conservation and violation, as well as for dark matter detection. While the multi-TeV squarks imply a Little Hierarchy Problem, intriguingly, small changes in parameter space to improve naturalness result in dramatic phase transitions to either electroweak-preservation or charge-breaking. In a Multiverse setting, the modest unnaturalness may then be explained by the “principle of living dangerously”.
Interventional radiologists are at risk of exposure to blood-borne pathogens in their day-to-day practice. Percutaneous exposure from unsafe sharps handling, mucocutaneous exposure from body fluid splashes, and glove perforation from excessive wear can expose the radiologist to potentially infectious material. The increasing prevalence of blood-borne pathogens, including hepatitis B and C, and human immunodeficiency virus, puts nurses, residents, fellows, and interventional radiologists at risk for occupational exposure. This review outlines suggestions to establish a culture of safety in the interventional suite.
Early focus of interventional oncologists was developing tools and imaging guidance, performing “procedures” acting as a skillful technician without knowledge of clinical patient outcomes, beyond post-treatment image findings. Interventional oncologists must deliver “treatments” and not “procedures”, and focus on clinically relevant outcomes, provide clinical continuity of care, which means stand at multidisciplinary tumor boards, see patients in consultation before treatment and for follow-up. Interventional oncologists have fought for the same “market” with surgery in a head to head, bloody competition called red ocean strategy in marketing terms, resulting in many aborted trials. Wide adoption of interventional oncology is facing the challenge to build evidence with overall survival as endpoint in randomized trials while the benefits of a treatment on overall survival are diluted by the effects of possible/inevitable subsequent therapies. Because interventional oncology is a disruptive force in medicine achieving same results as others (surgery) using different, less invasive approaches, patients where surgery is irrelevant can be target with a blue ocean strategy (to propose treatment where there is no competition). Recently interventional oncology has been included in the ESMO guidelines for colorectal cancer with oligometastatic disease with both surgical resection, and thermal ablation classified in the same category called “local ablative treatments”. Interventional oncologists have to shape the future by publications in oncologic journal, by being active members of oncology scientific societies, and use modern public megaphone (blog, video sharing, …) to disseminate information and let society know that interventional is not a me-too product but a disruptive treatment.
PurposeKnowledge of medical radiation exposure permits application of radiation protection principles. In our center, the first dedicated real-time, automated patient and staff dose monitoring system (DoseWise Portal, Philips Healthcare) was installed. Aim of this study was to obtain insight in the procedural and occupational doses.Materials and MethodsAll interventional radiologists, vascular surgeons, and technicians wore personal dose meters (PDMs, DoseAware, Philips Healthcare). The dose monitoring system simultaneously registered for each procedure dose-related data as the dose area product (DAP) and effective staff dose (E) from PDMs. Use and type of shielding were recorded separately. All procedures were analyzed according to procedure type; these included among others cerebral interventions (n = 112), iliac and/or caval venous recanalization procedures (n = 68), endovascular aortic repair procedures (n = 63), biliary duct interventions (n = 58), and percutaneous gastrostomy procedure (n = 28).ResultsMedian (±IQR) DAP doses ranged from 2.0 (0.8–3.1) (percutaneous gastrostomy) to 84 (53–147) Gy cm{sup 2} (aortic repair procedures). Median (±IQR) first operator doses ranged from 1.6 (1.1–5.0) μSv to 33.4 (12.1–125.0) for these procedures, respectively. The relative exposure, determined as first operator dose normalized to procedural DAP, ranged from 1.9 in biliary interventions to 0.1 μSv/Gy cm{sup 2} in cerebral interventions, indicating large variation in staff dose per unit DAP among the procedure types.ConclusionReal-time dose monitoring was able to identify the types of interventions with either an absolute or relatively high staff dose, and may allow for specific optimization of radiation protection.
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An effective spectroscopic method for estimating the degree of filling (porosity) of polymeric materials, the average size and the size distribution of the scattering particles of the filler within the polymer matrix, their anisotropy and the degree of orientation is proposed. The obtained spectral data are in good agreement with the results of optical and electron microscopy methods.
The effect of solvent on the structural, frontier orbital energies, global density-based descriptors, vibrational frequencies, and {sup 31}P NMR chemical shifts was examined for the syn-Cp{sub 2}Ti(η{sup 2}-C{sub 6}H{sub 4}-2-OMe)(PMe{sub 3}) complex by the self-consistent reaction field theory (SCRF) based on the polarizable continuum model (PCM). The studied spectroscopic parameters were correlated with the Kirkwood–Bauer–Magat (KBM) equation. Also, the response of the global density-based descriptors (chemical potential and hardness) in the presence of external electric field was studied. EDA, QTAIM, ELF, LOL, and NBO analyses were used for illustration of the Ti–C bond in this complex.
The first author's name is incorrect. The name should read T. Özdemir.
We are developing lumped-element kinetic inductance detectors (LEKIDs) designed to achieve background-limited sensitivity for far-infrared (FIR) spectroscopy on a stratospheric balloon. The spectroscopic terahertz airborne receiver for farinfrared exploration will study the evolution of dusty galaxies with observations of the [CII] 158µm and other atomic fine-structure transitions at z = 0.5–1.5, both through direct observations of individual luminous infrared galaxies, and in blind surveys using the technique of line intensity mapping. The spectrometer will require large format (~1800 detectors) arrays of dual-polarization sensitive detectors with NEPs of 1 × 10 –17 W Hz –1/2 . The low-volume LEKIDs are fabricated with a single layer of aluminum (20-nm-thick) deposited on a crystalline silicon wafer, with resonance frequencies of 100–250MHz. The inductor is a single meander with a linewidth of 0.4µm, patterned in a grid to absorb optical power in both polarizations. As a result, the meander is coupled to a circular waveguide, fed by a conical feedhorn. Initial testing of a small array prototype has demonstrated good yield and a median NEP of 4 × 10 –18 W Hz –1/2 .
Infrared radiation leakage through dielectrics in coaxial cabling can create unwanted quasiparticles in superconducting resonators if allowed to reach devices unattenuated. Modern experimental setups commonly incorporate epoxy-based filter blocks on readout and control lines in order to mitigate this effect; however, most of these multi-channel designs require specialized mounting hardware. Here, this investigation details the design and construction of single-channel inline infrared filters, and finds that their installation in the readout system for an aluminum resonator increased its quality factor by an average of 12% across a range of operating temperatures and powers. The option to incorporate general-purpose inline filters instead of designing custom filter blocks and mounts should prove more convenient for many newer experiments.
Carbon-fiber composite structures may demonstrate a defective behavior due to manufacturing induced anomalies (delamination, dis-bonds) or service related defectives (impact damage, water ingress). Thus, there is a need for a relatively fast and low cost non-intrusive testing schemes such as infrared thermography (IRT). Still, thermography testing requires calibrated samples and coupons to yield best results. The presented research demonstrates the novel use of 3D printing technology to generate IRT calibration samples. In this text, two carbon fiber reinforced polymer samples are 3D printed; the first mimics a 'back-drilled holes' type coupons, while the other is designed to embed air pockets similar to Teflon inserts. The generated samples are then tested using two IRT modalities; namely pulse thermography and lock-in thermography. Furthermore, the resulted thermograms are processed using a principle component analysis, to help highlight the variance of defectives in a consistent manner among the samples. This research findings offer insights on the variation of detectability between embedded and back-printed samples, which might be due to the inserts thickness.