bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological analysis of SZ and X-ray maps of galaxy clusters with Zernike polynomials
Authors: Capalbo Valentina , De Petris Marco , De Luca Federico , Cui Weiguang , Yepes Gustavo , Knebe Alexander , Rasia Elena , Ruppin Florian , Ferragamo Antonio
Published: January 2022

Several methods are used to evaluate, from observational data, the dynamical state of galaxy clusters. Among them, the morphological analysis of cluster images is well suited for this purpose. We report a new approach to the morphology, which consists in analytically modelling the images with a set of orthogonal functions, the Zernike polynomials (ZPs). We validated the method on mock high-resolution Compton parameter maps of synthetic galaxy clusters from The Three Hundred project. To classify the maps for their morphology we defined a single parameter, C, by combining the contribution of some ZPs in the modelling. We verify that C is linearly correlated with a combination of common morphological parameters and also with a proper 3D dynamicalstate indicator available for the synthetic clusters we used. We also show the early results of the Zernike modelling applied on Compton parameter maps of local clusters (z < 0:1) observed by the Planck satellite. At last, we report the preliminary results of this kind of morphological analysis on mock X-ray maps of The Three Hundred clusters.
Many-probes multi-object spatially-resolved analyses of galaxy clusters in the big data era
Authors: Castagna Fabio , Andreon Stefano , Trombetta Alberto , Landoni Marco
Published: January 2022

The thermal Sunyaev-Zeldovich (SZ) effect and the X-ray emission offer separate and highly complementary probes of the thermodynamics of the intracluster medium, particularly on their radial dependence. We already released JoXSZ, the first publicly available code designed to jointly fit SZ and X-ray data coming from various instruments to derive the thermodynamic radial profiles of galaxy clusters, including mass. JoXSZ follows a fully Bayesian forward-modelling approach, adopts flexible parametrization for the thermodynamic profiles and includes many useful options that users can customize according to their needs. We are including shear measurement in our joint analysis, and moving from single-cluster to multi-cluster analyses, allowing to quantify the heterogeneity of thermodynamic properties within the cluster population. At the same time, we are creating a suitable framework that effciently stores and optimally processes huge volumes of data being released by the current and new generation surveys.
CONCERTO at APEX: Installation and first phase of on-sky commissioning
Authors: Catalano A. , Ade P. , Aravena M. , Barria E. , Beelen A. , Benoit A. , Béthermin M. , Bounmy J. , Bourrion O. , Bres G. , De Breuck C. , Calvo M. , Désert F.-X. , Durán C.A , Duvauchelle G. , Eraud L. , Fasano A. , Fenouillet T. , Garcia J. , Garde G. , Goupy J. , Groppi C. , Hoarau C. , Hu W. , Lagache G. , Lambert J.-C. , Leggeri J.-P. , Levy-Bertrand F. , Macías-Pérez J. , Mani H. , Marpaud J. , Marton M. , Mauskopf P. , Monfardini A. , Pisano G. , Ponthieu N. , Prieur L. , Raffin G. , Roni S. , Roudier S. , Tourres D. , Tucker C. , Vivargent L.
Published: January 2022

CONCERTO (CarbON CII line in post-rEionisation and ReionisaTiOn) is a large field-of-view (FoV) spectro-imager that has been installed on the Cassegrain Cabin of Atacama Pathfinder EXperiment (APEX) telescope in April 2021. CONCERTO hosts 2 focal planes and a total number of 4000 Kinetic Inductance Detectors (KID), with an instantaneous FoV of 18.6 arcminutes in the range of 130-310 GHz. The spectral resolution can be easily tuned down to 1 GHz depending on the scientific target. The scientific program of CONCERTO has many objectives, with two main programs focused on mapping the fluctuations of the [CII] line intensity in the reionisation and postreionisation epoch (4.5<z<8.5), and on studying galaxy clusters via the thermal and kinetic Sunyaev-Zel’dovich (SZ) effect. CONCERTO will also measure the dust and molecular gas contents of local and intermediate-redshift galaxies, it will study the Galactic star-forming clouds and finally it will observe the CO intensity fluctuations arising from 0.3<z<2 galaxies.

The design of the instrument, installation at APEX and current status of the commissioning phase and science verification will be presented. Also we describe the deployment and first on-sky tests performed between April and June 2021.
The THREEHUNDRED project: The effect of baryon processes at galaxy cluster scale
Authors: Cui Weiguang
Published: January 2022

The role of baryon models in hydrodynamic simulations is still unclear. Future surveys that use cluster statistics to precisely constrain cosmological models require a better understanding of the baryonic effects. Using the hydro-simulated galaxy clusters from different baryon models (Gadget-MUSIC, Gadget-X and Gizmo-SIMBA) from the THREEHUNDRED project, we can address this question into more details. We find that the galaxy cluster mass change due to different baryon models is at a few per cent level. However, the mass changes can be positive or negative depending on the baryon models. Such a small mass change leaves a weak influence (slightly larger compared to the mass changes) on both the cumulative halo numbers and the differential halo mass function (HMF) above the mass completeness. Similarly to to the halo mass change, the halo mass or the HMF can be increased or decreased with respect to the dark-matter-only (DMO) run depending on the baryon models.
Dust Emission in Galaxies at Millimeter Wavelengths: Cooling of star forming regions in NGC6946
Authors: Ejlali G. , Adam R. , Ade P. , Ajeddig H. , André P. , Artis E. , Aussel H. , Beelen A. , Benoît A. , Berta S. , Bing L. , Bourrion O. , Calvo M. , Catalano A. , de Looze I. , De Petris M. , Désert F.-X. , Doyle S. , Driessen E.F. C. , Galametz M. , Galliano F. , Gomez A. , Goupy J. , Jones A.P. , Hughes A. , Katsioli S. , Kéruzoré F. , Kramer C. , Ladjelate B. , Lagache G. , Leclercq S. , Lestrade J.-F. , Macías-Pérez J.-F. , Madden S.C. , Maury A. , Mauskopf P. , Mayet F. , Monfardini A. , Muñoz-Echeverría M. , Nersesian A. , Perotto L. , Pisano G. , Ponthieu N. , Revéret V. , Rigby A.J. , Ritacco A. , Romero C. , Roussel H. , Ruppin F. , Schuster K. , Shu S. , Sievers A. , Smith M. W. S. L. , Tabatabaei F. S. , Tucker C. , Xilouris E.M. , Zylka R.
Published: January 2022

Interstellar dust plays an important role in the formation of molecular gas and the heating and cooling of the interstellar medium. The spatial distribution of the mm-wavelength dust emission from galaxies is largely unexplored. The NIKA2 Guaranteed Time Project IMEGIN (Interpreting the Millimeter Emission of Galaxies with IRAM and NIKA2) has recently mapped the mm emission in the grand design spiral galaxy NGC6946. By subtracting the contributions from the free-free, synchrotron, and CO line emission, we map the distribution of the pure dust emission at 1:15mm and 2mm. Separating the arm/interarm regions, we find a dominant 2mm emission from interarms indicating the significant role of the general interstellar radiation field in heating the cold dust. Finally, we present maps of the dust mass, temperature, and emissivity index using the Bayesian MCMC modeling of the spectral energy distribution in NGC6946.
Sunyaev Zel’dovich effect in galaxy clusters cavities: Thermal or non-thermal origin?
Authors: Marchegiani Paolo
Published: January 2022

Several galaxy clusters host X-ray cavities, often filled with relativistic electrons emitting in the radio band. In the cluster MS 0735.6+7421 the cavities have been detected through the Sunyaev Zel’dovich (SZ) effect, but it has not been possible to determine if this effect is thermal (produced by a very high temperature gas filling the cavity) or non-thermal (produced by the relativistic electrons that produce the diffuse radio emission detected in the cavity). In this paper we discuss the role of the density of the high temperature gas inside the cavities in determining whether the dominant SZ effect is the thermal or the non-thermal one, and how it can be possible to distinguish between the two possibilities, discussing the role of observations at higher energy bands.
Sunyaev Zel’dovich high resolution view of filamentary structures between galaxy clusters pairs
Authors: Radiconi Federico ,   for the ACT collaboration
Published: January 2022

Strong observational and theoretical evidences suggest that about half of the baryons in the Universe should lie outside galaxy clusters in a lowdensity and hot phase in filaments connecting galaxy clusters. Due to the low density, most of this filamentary plasma can not be detected by X-ray observatories. In particular cases of low redshift cluster pairs in the pre-merging phase, the Sunyaev Zel’dovich (SZ) effect can be used to observe the intercluster regions and detect the imprint of missing baryons.

The Abell 399-401 (A399-401) system is the perfect laboratory to test our ability to detect filamentary structures via the SZ effect with <~ 1′ angular resolution. This pair has been well studied at several frequencies: it exhibits double radio-halos, an excess of X-ray emission in the intercluster region and a synchrotron radio ‘ridge’ connecting the two clusters. Moreover the Planck satellite provided the first SZ detection of the gas between A399-401 despite the poor angular resolution (~ 10′) of its SZ map.

We have used an Atacama Cosmology Telescope (ACT) and Planck satellite Compton-y map (1:65′ angular resolution) that combines ACT data from 2008 to 2019 with Planck maps to study the A399-401 system in detail. We present the data analysis and results.
Mapping the intracluster medium temperature in the era of NIKA2 and MUSTANG-2
Authors: Ruppin F. , Adam R. , Ade P. , Ajeddig H. , André P. , Artis E. , Aussel H. , Beelen A. , Benoît A. , Berta S. , Bing L. , Bourrion O. , Brodwin M. , Calvo M. , Catalano A. , Decker B. , De Petris M. , Désert F.-X. , Doyle S. , Driessen E. F. C. , Eisenhardt P. R. M. , Gomez A. , Gonzalez A. H. , Goupy J. , Kéruzoré F. , Kramer C. , Ladjelate B. , Lagache G. , Leclercq S. , Lestrade J.-F. , Macías-Pérez J.-F. , Maury A. , Mauskopf P. , Mayet F. , McDonald M. , Monfardini A. , Moravec E. , Muñoz-Echeverría M. , Perotto L. , Pisano G. , Ponthieu N. , Revéret V. , Rigby A. J. , Ritacco A. , Romero C. , Roussel H. , Schuster K. , Shu S. , Sievers A. , Stanford S.A. , Stern D. , Tucker C. , Zylka R.
Published: January 2022

We present preliminary results from an on-going program that aims at mapping the intracluster medium (ICM) temperature of high redshift galaxy clusters from the MaDCoWS sample using a joint analysis of shallow X-ray data obtained by Chandra and high angular resolution Sunyaev-Zel’dovich (SZ) observations realized with the NIKA2 and MUSTANG-2 cameras. We also present preliminary results from an on-going Open Time program within the NIKA2 collaboration that aims at mapping the ICM temperature of a galaxy cluster at z = 0.45 from the resolved detection of the relativistic corrections to the SZ spectrum. These studies demonstrate how high angular resolution SZ observations will play a major role in the coming decade to push the investigation of ICM dynamics and non-gravitational processes to high redshift before the next generation X-ray observatories come into play.
Impact of H in H2O thermal scattering data on criticality calculation: uncertainty and adjustment
Authors: Rochman Dimitri , Vasiliev Alexander , Ferroukhi Hakim , Koning Arjan , Sublet Jean-Christophe
Published: January 2022

In this paper, the impact of the thermal scattering data for H in H20 is estimated on criticality benchmarks, based on the variations of the CAB model parameters. The Total Monte Carlo method for uncertainty propagation is applied for 63 keff criticality cases, sensitive to H in H20. It is found that their impact is of a few tenth of pcm, up to 300 pcm maximum, and showing highly non-linear distributions. In a second step, an adjustment is proposed for these thermal scattering data, leading to a better agreement between calculated and experimental keff values, following an increase of scattering contribution. This work falls into the global approach of combining advanced theoretical modelling of nuclear data, followed by possible adjustment in order to improve the performances of a nuclear data library.
Improved accuracy of eddy-current sensor based carrier lifetime measurement using laser excitation
Authors: Krisztián Dávid , Korsós Ferenc , Saegh Ilias , Paráda Gábor , Kovács Martin , Verdon Zita , Jobbágy Csaba , Tüttö Péter , Dong Xueqian , Deng Hao , Wang Shasha , Chen Xiaobo
Published: January 2022

In the manufacturing of modern solar cells, the early-phase quality inspection is crucial to detect harmful impurities and to reduce production waste. Thus, the charge-carrier lifetime measurement is beneficial before slicing the silicon ingot into wafers. Optimization of the widely used eddy-current detected photoconductance decay (e-PCD) technique for lifetime measurements is necessary to keep the pace with the new challenges appearing in photovoltaics. We investigated the dependence of the accuracy of the measurable carrier lifetime on the excitation laser parameters in the entire relevant carrier lifetime range. The complex behaviour of surface-recombination phenomena and its time evolution is studied by computer simulation. We optimized the components and parameters of the measurement setup and found that a 1064 nm laser is rather optimal compared to the 980 nm laser used previously. Using a longer wavelength laser source with elevated photon flux results in an improved accuracy of carrier lifetime recorded at Δn = 1015 cm−3 excess carrier concentration. A convincing similarity is found by comparing results from as-sliced and passivated surfaces. The optimized laser e-PCD method was compared to the flash-lamp based PCD method (known as QSSPC). Results agree very well for longer carrier lifetimes for which both systems evaluates the PCD curves in transient mode. However, for lower carrier lifetimes the universal transient mode operation of the e-PCD method is advantageous in terms of consistency.
Considering mesohabitat scale in ecological impact assessment of sediment flushing
Authors: Doretto Alberto , Espa Paolo , Salmaso Francesca , Crosa Giuseppe , Quadroni Silvia
Published: January 2022

Benthic macroinvertebrates respond to several factors characterizing the physical habitats, as water depth, current and streambed substrate. Thus, anthropogenic disturbances altering these factors may have different effects on benthos, also depending on mesohabitats. These disturbances include sediment flushing operations, commonly carried out to recover reservoir capacity, and investigating their effects at mesohabitat scale could be relevant for an adequate ecological impact assessment of these operations. Here, we compared benthic macroinvertebrate communities sampled before and after a controlled sediment flushing operation in three different mesohabitats (a pool, a riffle and a step-pool) of an Alpine stream. Contrary from expectations, the composition of macroinvertebrate assemblages was not significantly different among mesohabitats. Moreover, the impact of sediment flushing was more significant in terms of density rather than in richness. Two stressor-specific indices were tested, but only one (the Siltation Index for LoTic EcoSystems − SILTES) clearly detected the impact of sediment flushing on the macroinvertebrate community structure. Finally, some differences in the temporal trajectories and recovery times to pre-flushing conditions were observed among mesohabitats, both if the three mesohabitats were considered separately and if all their possible combinations were accounted for. Particularly, riffle was the most sensitive mesohabitat, not fully recovering one year after the sediment disturbance.
Mathematical analysis of Goldstein’s model for time-harmonic acoustics in flows
Authors: Bensalah Antoine , Joly Patrick , Mercier Jean-Francois
Published: January 2022

Goldstein’s equations have been introduced in 1978 as an alternative model to linearized Euler equations to model acoustic waves in moving fluids. This new model is particularly attractive since it appears as a perturbation of a simple scalar model: the potential model. In this work we propose a mathematical analysis of boundary value problems associated with Goldstein’s equations in the time-harmonic regime.
Assessment of radiation protection awareness and safety practices among nurses in nuclear medicine departments in Saudi Arabia
Authors: Alyami A. , Majrashi N. , Shubayr N. , Alomairy N. , Abuhadi N.
Published: January 2022

This study was aimed to evaluate the level of radiation protection awareness and safety practices among nurses working in nuclear medicine departments (NMDs) in governmental, private, and specialized hospitals in Saudi Arabia. A cross-sectional survey was used and distributed to 42 nurses who worked in NMDs without rotation between other radiology departments. A total of 29 nurses (37.9% males and 62.1% females) operating in 12 NMDs across the country responded to the survey, with a 69% response rate. Most of the nurses who responded to this survey were 20–35 years old. Nearly 83% of the nurses in this study had bachelor’s degrees and about 62.1% of the respondents had two to five years of work experience. In the results, it was revealed that the satisfactory awareness score among the nurses working in NMDs was 93.1%, with a mean radiation protection awareness score of 9.58 ± 1.0 (out of 12). However, only 27.5% of the nurses had acceptable safety practices, with a mean score of 2.48 ± 0.1 (out of 6). In the results, it was shown that satisfactory awareness regarding radiation protection among the nurses working in NMDs was significantly associated with gender (P = 0.04,χ2 = 12.6) and nurses who received training courses (P = 0.01,χ2 = 15.2). The findings of this study are an indication of the importance of training and continuing to educate nurses about radiation protection and radiological procedures in NMDs, which improve the levels of radiation protection awareness and safety practices.
Probabilistic risk assessment of radiotherapy application
Authors: Özbay Ç. , Özbay T. , Güler Yiğitoğlu A. , Bayburt M.
Published: January 2022

The recent rapid development and increasing complexity of radiotherapy devices and applications has increased the importance of correct and safe treatment. Risk management is very important in radiotherapy (RT), because incorrect treatment can have serious consequences in terms of mortality or morbidity. However, there are currently few studies on risk analysis in RT. This quantitative and qualitative study of the radiotherapy system (all radiotherapy process) uses the fault tree method, one of the probabilistic risk assessment methods in radiotherapy applications, which is used to devise accident preventive actions. First of all, RT applications were divided into simulation, treatment planning and treatment delivery. For each, work flow charts were determined, and fault trees were created in SAPHIRE (Systems Analysis Programs for Hands-on Integrated Reliability Evaluations) software. Fault probabilities were determined using the expert judgment method. This analysis allowed the identification of the weak points of the system, both qualitatively and quantitatively. The analyzes also revealed that there was a 0.5% occurrence probability of a top event, determined as an incorrect dose or dose distribution in RT. It was determined that the greatest contribution to this probability value was matching error with image guidance, 7.88%. Fault tree analysis (FTA) was found to facilitate a detailed examination of the radiotherapy system. After the risk analysis, the appropriate quality control method for weak points should be determined and implemented for safety management in radiotherapy.
Performance analysis of an M/G/1 queue with bi-level randomized (p, N1, N2)-policy
Authors: Kuang Xinyu , Tang Yinghui , Yu Miaomiao , Wu Wenqing
Published: January 2022

This paper proposes an M/G/1 queueing model with bi-level randomized (p, N1, N2)-policy. That is, after all of the customers in the system are served, the server is closed down immediately. If N1(≥ 1) customers are accumulated in the queue, the server is activated for service with probability p(0 ≤ p ≤ 1) or still left off with probability 1 − p. When the number of customers in the system becomes N2(≥ N1), the server begins serving the waiting customers until the system becomes empty again. Using the total probability decomposition technique and the Laplace transform, we study the transient queue length distribution and obtain the expressions of the Laplace transform of the transient queue-length distribution with respect to time t. Then, employing L’Hospital’s rule and some algebraic operations, the explicit recursive formulas of the steady-state queue-length distribution, which can be used to accurately evaluate the probabilities of queue length, are presented. Moreover, some other important queuing performance indices, such as the explicit expressions of its probability generating function of the steady-state queue-length distribution, the expected queue size and so on, are derived. Meanwhile, we investigate the system capacity optimization design by the steady-state queue-length distribution. Finally, an operating cost function is constructed, and by numerical calculation, we find the minimum of the long-run average cost rate and the optimal bi-level threshold policy
(N*1,N*2)

that satisfies the average waiting time constraints.
Incidence and Outcomes Associated with 6,841 Isolated Distal Deep Vein Thromboses in Patients with 13 Common Cancers
Authors: Mahajan Anjlee , Brunson Ann , Eldredge Joanna , White Richard H. , Keegan Theresa H. M. , Wun Ted
Published: January 2022

Introduction The epidemiology of isolated distal deep venous thrombosis (iDDVT) among cancer patients is not well described, particularly the incidence of recurrent venous thromboembolism (rVTE) and effect on mortality by cancer type.

Methods The cumulative incidence (CI) of iDDVT was determined for patients with 13 common cancers between 2005 and 2017 using the California Cancer Registry linked to the California Patient Discharge and Emergency Department Utilization datasets. The CI of rVTE was calculated and association of incident cancer-associated thrombosis (CT) location with rVTE was determined using Cox proportional hazards regression models. The association of incident CT location with overall and cancer-specific mortality was determined using Cox models, stratified by cancer site, and adjusted for individual characteristics.

Results Among 942,109 cancer patients, CT occurred in 62,003 (6.6%): of these, 6,841 (11.0%) were iDDVT. Compared with more proximal sites of CT, iDDVT was associated with similar risk for rVTE. IDDVT was associated with increased mortality across all cancer types when compared with patients without CT (hazard ratio: 1.56–4.60). The effect of iDDVT on mortality was similar to that of proximal DVT (pDVT) for most cancers except lung, colorectal, bladder, uterine, brain, and myeloma, where iDDVT was associated with a lesser association with mortality.

Conclusion iDDVT represented 11% of CT. The risk of rVTE after iDDVT was similar to other sites of CT and rVTE occurred in more proximal locations after an incident iDDVT. IDDVT was associated with increased mortality and this effect was similar to that of pulmonary embolism or pDVT for most cancer types.
δ-Keto Aminoacrylonitriles and δ-Keto Aminoenones from 1-Pyrrolines, Cyanoacetylenes, and Acetylenic Ketones
Authors: Trofimov Boris A. , Oparina Ludmila A. , Mal’kina Anastasiya G. , Kolyvanov Nikita A. , Ushakov Igor A. , Saliy Ivan V. , Apartsin Konstantin A.
Published: January 2022

The ring-opening/functionalization of 1-pyrrolines by cyano­acetylenes or acetylenic ketones (20–80 °C, MeCN, H2O) affords δ-keto aminoacrylonitriles and δ-keto aminoenones, mostly as the Z-isomers, in up to 85% yields. The synthesis involves C(2)–N bond cleavage in the intermediate hemiaminal resulting from the intermediate 1,3(4)-dipolar 1-pyrroline/acetylene complexes and water.
Synthesis of Dibenzotetrathiafulvalenes of Oxalic Acid with Electron-Rich Aromatic 1,2-Dithiols and Application to Dithioacetalization with 9-Fluorenecarboxylic Acids or Dicarboxylic Acids
Authors: Sakai Norio , Minato Kohei , Nakata Shota , Ogiwara Yohei
Published: January 2022

We have developed a two-step synthesis of dibenzotetrathiafulvalene (DBTTF) derivatives by combining the indium-catalyzed reductive dithioacetalization of oxalic acid and electron-rich aromatic dithiols with a subsequent oxidation of the resultant dithioacetals. The same transformation of electron-rich aromatic dithiols with either 9-fluorenecarboxylic acid derivatives or dicarboxylic acids effectively produced the corresponding benzo-1,3-dithiafulvene derivatives.
Acute Severe Colitis: The Need for Joint Management between Gastroenterologists and Surgeons
Authors: Fleshner Phillip , Melmed Gil Y.
Published: January 2022

The management of hospitalized patients with acute, severe ulcerative colitis involves close coordination among a multidisciplinary team. For patients not improving on intravenous corticosteroids, surgical consultation should be sought. The remaining hospital course requires frequent communications between the gastroenterologist managing the medical aspects of care, and the colorectal surgeon involved in planning for potential surgery, to optimize patient outcomes. This comanagement includes joint decision-making around the timing of surgery, minimizing medications associated with postoperative morbidity, addressing nutritional and psychosocial aspects of the patient's condition, and planning for a coordinated postoperative course. In this review, we highlight these aspects of care and the need for coordination and communication between gastroenterologists and surgeons in the management of acute severe colitis.
A Multi-Disciplinary Approach to Perianal Fistulizing Crohn's Disease
Authors: Wiseman Jacob , Chawla Tanya , Morin Frederic , de Buck van Overstraeten Anthony , Weizman Adam V.
Published: January 2022

Perianal fistulizing Crohn's disease represents a severe phenotype associated with significant morbidity. Patients with perianal fistulizing disease are more likely to have a severe disease course and have significant reductions in quality of life. Moreover, these patients are at risk for the development of distal rectal and anal cancers. Given the complexity and severity of this patient group, the management of perianal Crohn's disease must be undertaken by a multidisciplinary team. The gastroenterologist and colorectal surgeon play a critical role in the diagnosis and management of perianal fistulizing disease. An examination under anesthesia provides critical information and is an essential part of the work-up of complex perianal fistulas. The radiologist also plays a central role in characterizing anatomy and assessing response to treatment. Several imaging modalities are available for these patients with magnetic resonance imaging as the imaging modality of choice. Perianal disease developing after ileal pouch-anal anastomosis represents a particularly challenging form of fistulizing disease and requires a multidisciplinary clinical and radiologic approach to differentiate surgical complications from recurrent Crohn's disease.
Increasing Incidence of Sternoclavicular Joint Infections in Intravenous Drug Users
Authors: Orbay Hakan , Seng Sirivan , Kim Daniel Wonsuk , Geller Charles M.
Published: January 2022

Sternoclavicular joint septic arthritis is rarely seen in the general population. The majority of cases are seen in intravenous drug users. Given the lack of reported cases in the literature, there is no standardized treatment algorithm for this disease. Described treatment methods range from medical management to wide local debridement. The incidence of sternoclavicular joint septic arthritis will likely continue to increase with rising usage of intravenous drugs in the United States. Within the past year, our institution treated four cases.
Technical Aspects of High-Resolution Color-Coded Duplex Sonography for the Design of Perforator Flaps
Authors: Kehrer Andreas , Heidekrueger Paul I. , Lonic Daniel , Klein Silvan , Anker Alexandra , Taeger Christian D. , Biermann Niklas , Jung Ernst Michael , Prantl Lukas , da Silva Natascha Platz Batista
Published: January 2022

Background Technical aspects are of utmost significance for an efficient execution in designing perforator flaps with high-resolution color-coded Duplex sonography (CCDS). The following study evaluates decisive factors for a successful microvessel examination conducted by the microsurgeon.

Methods Technical knowledge presented in this study was based on a series of more than 200 perforator flaps planned with CCDS. Flap reconstructions were performed at the University Hospital Regensburg, Germany, from July 2013 to January 2021. Standard high-resolution ultrasound (US) devices with linear multifrequency transducers of 4 to 18 MHz were used. Modes and device settings were evaluated regarding applicability by microsurgeons. Key steps for safe perforator identification and further optional steps for additional assessment should be discriminated.

Results Different US modes including brightness mode (B-mode), color flow (CF), power Doppler (PD), pulse wave (PW), and blood flow (B-Flow) were used. Transducers from 15 MHz and up were favorable to detect microvessels. Knobology of a standard US device regarding buttons, switches, and specific onscreen options with relevance for perforator mapping was subcategorized in four different groups. For qualitative and quantitative evaluation of microvessels, different US modes were tested with respect to their usefulness.

Vital elements of the CCDS exam are disaggregated into three key steps for safe perforator identification and three optional steps for further perforator characterization. A standardized protocol for the CCDS exams was applied. Downregulation of pulse-repetition frequency/scale to adapt device sensitivity to slow-flow velocities represented the most important criterion to visualize microvessels.

Qualitative microvessel evaluation was performed in B-mode, CCDS, PD mode, and B-Flow mode. Quantitative assessment was executed using PW-mode and CCDS measuring the microvessels' diameter (mm) and flow characteristics. Quantitative information may be obtained using PW-mode and the distance-measuring tool in CF-mode.

Conclusion Technical aspects with respect to proper device trimming and application decisively impact CCDS-guided perforator vessel identification and evaluation.
Symmetry-specific orientational order parameters for complex structures
Authors: Logan Jack A. , Mushnoori Srinivas , Dutt Meenakshi , Tkachenko Alexei V.
Published: January 2022

A comprehensive framework of characterizing complex self-assembled structures with a set of orientational order parameters is presented. It is especially relevant in the context of using anisotropic building blocks with various symmetries. Two classes of tensor order parameters are associated with polyhedral nematic and bond orientational order. For the latter, a variation of classical bond order parameters (BOPs) is introduced, which takes advantage of the symmetry of constituent particles and/or expected crystalline phases. These symmetrized BOPs can be averaged over an entire system or assigned locally to an individual bond. By combining that with the bond percolation procedure, one is able to identify coherent domains within a self-assembled structure. As a demonstration of the proposed framework, we apply it to a simulated hybrid system that combines isotropic and patchy particles with octahedral symmetry. Not only does the methodology allow one to identify individual crystalline domains but also it detects coherent clusters of a peculiar compact amorphous structure that is not space-filling and lacks any long-range order.
Fast estimation of ion-pairing for screening electrolytes: A cluster can approximate a bulk liquid
Authors: Muralidharan Ajay , Yethiraj Arun
Published: January 2022

The propensity for ion-pairing can often dictate the thermodynamic and kinetic properties of electrolyte solutions. Fast and accurate estimates of ion-pairing can thus be extremely valuable for supplementing design and screening efforts for novel electrolytes. We introduce an efficient cluster model to estimate the local ion-pair potential-of-mean-force between ionic solutes in electrolytes. The model incorporates an ion-pair and a few layers of explicit solvent in a gas-phase cluster and leverages an enhanced sampling approach to achieve high efficiency and accuracy. We employ harmonic restraints to prevent solvent escape from the cluster and restrict sampling of large inter-ion distances. We develop a cluster ion-pair sampling tool that implements our cluster model and demonstrate its potential utility for screening simple and poly-electrolyte systems.
Elucidating the solution structure of the K-means cost function using energy landscape theory
Authors: Dicks L. , Wales D. J.
Published: January 2022

The K-means algorithm, routinely used in many scientific fields, generates clustering solutions that depend on the initial cluster coordinates. The number of solutions may be large, which can make locating the global minimum challenging. Hence, the topography of the cost function surface is crucial to understanding the performance of the algorithm. Here, we employ the energy landscape approach to elucidate the topography of the K-means cost function surface for Fisher’s Iris dataset. For any number of clusters, we find that the solution landscapes have a funneled structure that is usually associated with efficient global optimization. An analysis of the barriers between clustering solutions shows that the funneled structures result from remarkably small barriers between almost all clustering solutions. The funneled structure becomes less well-defined as the number of clusters increases, and we analyze kinetic analogs to quantify the increased difficulty in locating the global minimum for these different landscapes.
Learning through digital technologies among pre-primary school children
Authors: Butler Yuko Goto
Published: January 2022

In response to the growing global demand for teaching additional language(s) to very young children (ages 2–6), an increasing supply of digital technologies purports to assist pre-primary school children with their language learning. Focusing on TV/videos, digital picture books, and social robots, this paper examined the small body of empirical research on the effect of these digital technologies on very young second or foreign language learners and bolstered this research with similar studies conducted among very young children learning a first language. The paper identifies possibilities and limitations of using such technologies and documents how they can be used effectively with young language learners. Two key elements for effective use of digital technologies emerged from the examination of the relevant studies: (a) digital devices and applications must have developmentally appropriate content and functions; and (b) children need to have meaningful interaction with adults or digital agents while using digital technology. The paper concludes with two implications for future research: (a) the need to have critical discussions when designing digital technologies for and using digital technologies with young children; and (b) the need to pay greater attention to individual differences in children’s attitudes and preferences concerning different digital technologies.
Child-centred ethics in second language education
Authors: Pinter Annamaria
Published: January 2022

This article aims to provide an overview of the types of questions and concerns adult researchers working with children in L2 education need to consider when it comes to navigating research ethics. Questions and dilemmas relating to ethical practice in child-focussed research are complex, and will be rooted in political, legal and contextual concerns, and interpretations of what is ethical in any one project will depend on the adult researcher’s convictions about research paradigms, their epistemological stance and their beliefs and priorities in the given situation. This article suggests five main questions to consider when it comes to research with children. All five components are equally important and decisions relating to one component will influence all others in the framework. This paper examines the complexities in more detail, discusses some differences relevant in the two main ‘paradigms’ of child-focussed research and how these principles interact with the constraints and the affordances of the local contexts, the focus of the intended study and the background and personal theories of the adult researcher.
Bilateral key comparison EURAMET.EM-K11.1 "AC-DC Voltage Transfer Difference at Low Voltages"
Authors: Renner Jeannine , Heine Gernot , Waldmann Wolfgang
Published: January 2022

Main text

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Part I. Nanobubbles in pulsed laser fields for anticancer therapy: in search of adequate models and simulation approaches
Authors: Kostyukov A S , Isaev I L , Ershov A E , Gerasimov V S , Polyutov S P , Karpov S V
Published: January 2022

We numerically investigate the conditions for the laser-induced formation of nanobubbles in aqueous medium around plasmonic nanoparticles (NPs) bound to the malignant cell membranes that is considered as the method of their irreversible damage. We proposed employing the versatile and accessible simulation software as a research tool based on the finite volume method underlying the ANSYS Fluent package and supplemented with our user-defined functions that adapt it to solution of the stated problems. This adaptation allows to verify the model using experimental data for the same conditions. We determined the conditions for the pressure growth on the cell membrane at the initial moment of bubble formation significantly exceeding the threshold of irreversible damage. The model can be used for investigation of hydrodynamic effects accompanying irradiation of plasmonic NPs using both different types of pulsed lasers and ideally absorbing NPs with resonance in the hemoglobin spectral transparency range, as well as to uncover previously unknown effects. They include the conditions for localization of a damaging factor non-affecting the normal cells, the conditions for generation of ultrahigh pressure pulse that enables to damage the cell membrane and precedes formation of thin vapor shell around NPs, which, unlike large bubbles, requires registration using highly sensitive experimental measurements. An extensive overview of key publications summarizing the state-of-art in this area is presented.
Topological magnetic hysteresis in single crystals of CeAgSb2 ferromagnet
Authors: Prozorov Ruslan , Bud’ko Sergey L , Canfield Paul C
Published: January 2022

Closed-topology magnetic domains are usually observed in thin films and in an applied magnetic field. Here we report the observation of rectangular cross-section tubular ferromagnetic domains in thick single crystals of CeAgSb2 in zero applied field. Relatively low exchange energy, small net magnetic moment, and anisotropic in-plane crystal electric fields lower the domain wall energy and allow for the formation of the closed-topology patterns. The tubular domain structure irreversibly transforms into a dendritic pattern upon cycling the magnetic field. This transition between closed and open topologies results in a ‘topological magnetic hysteresis’— the actual hysteresis in magnetization, not due to the imperfections and pinning, but due to the difference in the pattern morphology. Similar physics was suggested before in pure type-I superconductors and is believed to be a generic feature of other nonlinear single (present case), or two-phase (type-I superconductor) systems where the effects similar to demagnetization (shape-dependent macroscopic variation of properties) lead to pattern formation.
Mitigating effects of sublethal and lethal whole-body gamma irradiation in a mouse model with soluble melanin
Authors: Malo Mackenzie E , Frank Connor , Khokhoev Elbrus , Gorbunov Andrey , Dontsov Alexander , Garg Ravendra , Dadachova Ekaterina
Published: January 2022

The field of radiation countermeasures is growing, however, currently there are no effective and non-toxic compounds which could be administered orally to the individuals post exposure to high doses of ionising radiation. The pigment melanin is ubiquitous through all kingdoms of life and provides selective advantage under radiation stress through its role as a chemical and physical shield, and its capacity to respond and react to exposures. Soluble allomelanin was administered to mice following whole-body exposure to lethal or sublethal doses of gamma radiation to determine its capacity to mitigate the effects of acute radiation syndrome, and its utility as a radiation countermeasure. Allomelanin has shown a trend to improve survival post an 8 Gy sublethal radiation exposure when administered up to 48 h post-irradiation. Furthermore, it improved median and overall survival to a 10 Gy lethal radiation exposure, specifically when administered at 24 h post-irradiation. Histological analysis on the jejunum region of the small intestine of this treatment group indicated that alterations of the mucosal and submucosal architecture, and disruption of the lymphatic system associated with lethal radiation exposure were mitigated when allomelanin was administered at 24 h post-irradiation. Based on this work soluble allomelanin derived from a fungal source could serve as an easily sourced, cost-effective, and viable countermeasure to accidental radiation exposure and merits further investigation.
Development of a thoron chamber for calibration of thoron monitors under natural wind speed conditions
Authors: Lv Lidan , He Zhengzhong , Xiao Detao , Qiu Shoukang
Published: January 2022

To examine the response of diffusion-type detectors for thoron under wind speeds similar to natural air ventilation, a special design thoron chamber was developed with a dynamic circulating air-flow field forced by fans. Wind speeds of 0–0.52 m s−1 were adjusted by control of the fan rotation rate according to a linear model, with higher wind speeds contributing to more homogenous air flow status. Thoron concentrations, ranging between 3.2 × 103 and 3.7 × 104 Bq m−3, were easily available through different injection conditions and 220Rn gas sources with high and stable emanation coefficient. The stability and homogeneity of thoron concentrations was controlled within 5.0% and the concentrations in the direction of wind speed had minimal differences compared with the other direction. Higher wind speeds also improved the stability and homogeneity of thoron concentrations. The design and construction of the thoron chamber functioned well in controlling thoron concentration. The response of an AlphaGUARD monitor to thoron was examined in the thoron chamber under different wind speeds. The study revealed a monitor response to thoron (rates of thoron infiltration into the detection chamber of the monitor) respectively was from 0.044 to 0.065 under winds speeds from 0.05 to 0.51 m s−1. Reproducible and controlled expourse conditions can be provided for testing thoron monitors.
A study on surface-temperature measurement by means of a vacuum-arc cathode under different current conditions
Authors: Yang Zongju , Dai Jingmin , Zhang Jianguo
Published: January 2022

Accurate detection and analysis of the cathode surface temperature delivers an important reference value as regards the prediction of electrode life and corrosion degree, a thorough study of the vacuum-breakdown phenomenon, design and application of the vacuum-arc ion source and vacuum switch. In this paper, multispectral true temperature measurement T of the surface temperature field of pulsed vacuum arc cathode materials under different discharge currents is carried out. Firstly, aiming at solving the problem of synchronous imaging measurement of the temperature field across the cathode of pulsed vacuum arc, a multi-wavelength monochromatic image-acquisition optical path is designed, based upon the image acquisition module of a high-speed monochrome camera. Also, multiple monochromatic spectral radiation images of the target are synchronously acquired on the focal plane of the same monochrome camera detector. As a result, the spectral-radiation image information of multiple wavelengths can be obtained in a single exposure time, which greatly shortens the temperature-field image acquisition time. Secondly, based upon the multispectral true-temperature calculation method, high-speed multispectral imaging measurement of the target temperature field is realized. Finally, the two-dimensional true temperature distribution of the cathode temperature field under different current conditions was studied by setting up an experimental platform for measuring the cathode temperature of the vacuum arc under different current conditions.
Experimentally validated x-ray image simulations of 50 μm x-ray PIV tracer particles
Authors: Parker Jason T , Mäkiharju Simo A
Published: January 2022

We evaluate Beer–Lambert (BL) ray-tracing and Monte Carlo N-Particle (MCNP) photon tracking simulations for prediction and comparison of x-ray imaging system performance. These simulation tools can aid the methodical design of laboratory-scale x-ray particle image velocimetry (XPIV) experiments and tracer particles by predicting image quality. Particle image signal-to-noise ratio (SNR) is used as the metric of system performance. Simulated and experiment data of hollow, silver-coated, glass sphere tracer particles (AGSF-33) are compared. As predicted by the simulations, the AGSF-33 particles are visible with a SNR greater than unity in 100 ms exposure time images, demonstrating their potential as x-ray PIV or particle tracking velocimetry (XPTV) tracers. The BL approach predicts the image contrast, is computationally inexpensive, and enables the exploration of a vast parameter space for system design. MCNP simulations, on the other hand, predict experiment images slightly more accurately, but are more than an order of magnitude more computationally expensive than BL simulations. For most practical XPIV system design applications, the higher computational expense of MCNP is likely not justified by the modest accuracy improvement compared to BL.