bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuner Loop Based on FPGA for Petra Cavity at TPS Booster Ring
Authors: Changf F.Y. , Liu Z. K. , Yeh M.S. , Lo C. H. , Chung F. T , Chen L. J. , Chang M. H. , Lin M. C. , Chang S. W. , Li Y. T. , Wang C.
Published: January 2024

The low-level radio frequency system of the Taiwan Photon Source, TPS, booster ring was replaced by the digital low-level RF system, DLLRF, in 2018. After that, the phase drift compensation loop for energy-saving operation and the tuner loop were also implemented in the DLLRF system sequentially. We used Altera-DE3 to build the core of DLLRF and handle the high-speed ADC/DAC procedure for RF signal sampling. As we con-sider the response time of the tuner, we choose an-other low-cost board, Altera-DE0-Nano, to develop the tuner loop for 5-Cell-Petra-Cavity. It has an eight-channel 12-bits-ADC, 150 ksps, ADC128S022, to detect the positions of two tuners and two transmitted powers sampled from two cells of the 5-Cell-Petra-Cavity for a power balance function. The phase information of for-ward power and cavity gap voltage will come from the Altera-DE3 to tell the tuner loop in the Altera-DE0-Nano whether the cavity is on resonance or not. The tuner loop controls the cavity to work not only at the resonance frequency but also with a balanced electric field distribution. This study presents the tuner loop’s architecture, including the locking resonance frequency and field balance functions. The performance of the field balance function is observed by the archive data of the two tuners positions and two transmit power signals.
Installation and integrated testing of magnets for the ESS Linac
Authors: Trachanas E , Gevorgyan A , McKenzie D , Tabatadze L , Svensson F , Jones B , Martins C , Fereira M J , Nicosia D , Castranovo D , Aden P
Published: January 2024

The European Spallation Source (ESS) linear accelerator is designed to accelerate a 62.5 mA, 2.86 ms, 14 Hz proton beam up to 2 GeV at the entrance of a rotating tungsten (W) target. Normal Conducting Linac (NCL) and Superconducting Linac (SCL) parts of the accelerator contain over 200 quadrupole, dipole and corrector magnets of different types and parameters for beam envelope and trajectory control. All magnets have been provided to ESS by in-kind collaborators and research institutes across Europe. Following the delivery of these components and their respective power converters to ESS, this proceeding presents the status of the installation together with the methodology and first obtained results from system local and integrated testing phase.
Damage experiment with superconducting sample coils - experimental setup and observations during beam impact
Authors: Gancarcik D. , Abusaif F. , Bordini B. , Bernhard A. , Bonura M. , Favre M. , Glamann N. , Grau A. , Hernalsteens C. , Saez de Jauregui D. , Müller A.-S. , Senatore C. , Thomsen S. D. , Wiesner C. , Wollmann D. , Zurmuehle D.
Published: January 2024

The damage mechanisms and limits of superconducting accelerator magnets due to the impact of high-intensity particle beams have been subject to extensive studies in the past years at CERN. Recently an experiment with dedicated sample coils made from Nb–Ti and Nb3Sn strands was performed at CERN’s HiRadMat facility. This paper describes the design and construction of the sample coils as well as the results of their qualification before the beam impact. In addition, the experimental setup will be discussed. Finally, measurements during the beam experiment like the beam-based alignment, the observations during the impact of 440GeV protons on the sample coils and the achieved hot-spots and temperature gradients will be presented.
Investigations on NbTi superconducting racetrack coils under pulsed-current excitations
Authors: Abusaif F , Bernhard A , Bründermann E , Gancarcik D , Glamann N , Grau A , Saez de Jauregui D , Müller A-S
Published: January 2024

One of the key issues in the technology of superconductors is the protection against quenches. When designing a superconductor as a magnet, a coil or even current leads, the design should be made such that the superconductor withstands all operational conditions, especially those occurring rapidly, as fast discharges or pulsed loads. A model for a superconducting racetrack coil based on NbTi winding is investigated under pulsed transport current conditions (zero external field) utilizing finite element analysis within the Simulia Opera platform. A pulse duration of a few milliseconds and a peak current exceeding 1 kA is yielded by discharging a capacitor into an RLC circuit that includes the superconductor coil as an element. A quench multi-physics analysis has been performed comprising both thermal and electromagnetic solutions. The transition to normal state and quench occurrence has agreed with the expected critical curve together with the load-line estimated for the existing coil geometry.
A nanosecond pulse power supply for grid-controlled electron gun used in HALF
Authors: Xu C Y , Shang L , Shang F L , Song W B
Published: January 2024

Hefei Advanced Light Facility (HALF) uses a grid-controlled thermionic cathode gun as its electron source of the linear accelerator. The nanosecond grid-controlled power supply is an important part of the electron gun power supply system, and its performance will affect the quality of the beam. To achieve the requirements of the electron gun for nanosecond pulse power supply, we use the series-parallel multi-stage avalanche transistor scheme to achieve nanosecond fast pulse output. The test results show that the power supply not only can meet the requirements of HALF for its electron gun but also have good waveform repeatability and amplitude stability.
Using supervised machine learning in power converters design for particle accelerators – Application to magnetic components design
Authors: Cajander D , Aguglia D , Viarouge I , Viarouge P
Published: January 2024

This paper presents an efficient application of Ma-chine Learning (ML) to derive models for accurately predicting the inductance value and mechanical constraints in widely used air-cored inductors in power electronics systems for accelerators. The ML is trained on Finite Elements Analyses (FEA) obtained data. The obtained Artificial Neural Network (ANN) based models are then used in a numerical optimization environment able to efficiently provide optimal solution in terms of speed and accuracy.
Design and experimental research of UHV flanges for the Hefei Advanced Light Facility
Authors: Bian Baoyuan , Hong Yuanzhi , Wang Sihui , Fan Le , Ge Xiaoqin , Fang Jianwei , Zhang Wenli , Wang Yong
Published: January 2024

The Hefei Advanced Light Facility (HALF) is a diffrac-tion-limited storage ring (DLSR) light source based on the compact multi-bend achromat (MBA) lattice. There-fore, the gaps between those focusing magnets are small. The commonly used ConFlat® flange, with a large axis dimension, is not suitable for the compact lattice in HALF. In this work, a stainless steel tapered flange fas-tened by a chain clamp has been designed for its smaller axis dimension. Two types of sealing structures are used, which are knife-edge and spring-energized metal C-ring structures, respectively. The copper gaskets with and without silver coating are used for knife-edge flange, respectively. Besides, the spring-energized metal C-ring is manufactured by SUS 304 with a tin layer of 50 μm. These flanges and chain clamps were made of SUS 304, and their vacuum properties were tested. The results indi-cate that these UHV flanges can meet the demands for the vacuum system of HALF.
Operational experience of a low beam coupling impedance injection kicker magnet for the CERN SPS ring
Authors: Barnes M J , Bartmann W , Díaz M , Ducimetière L , Favia G , Feliciano L , Kramer T , Namora V , Standen D , Stadlbauer T , Trubacova P , Velotti F , Zannini C
Published: January 2024

The CERN SPS injection kicker magnets (MKP) were developed in the 1970’s, before beam power deposition was considered an issue. There are two types of these magnets in the SPS: MKP-S (small aperture) and MKP-L (large aperture) versions. The MKP-L magnets are very lossy from a beam impedance perspective: this would be an issue during SPS operation with the higher intensity beams needed in the future for HL-LHC. Hence, a beam screen has been developed, which is inserted in the aperture of each MKP-L module. The screen consists of silver fingers applied to alumina U-shaped chambers: the fingers have been optimized to achieve both adequately low beam induced power deposition and good high voltage (HV) behaviour. A surface coating, with a low secondary electron yield, is applied to the inner surface of the alumina chambers to reduce dynamic vacuum. The low-impedance MKP-L has been extensively HV tested in the lab before installation in the SPS. This paper briefly presents the design and focuses on the operational experience in the SPS, including heating and vacuum.
Beam-Impact Validation of HL-LHC Collimator Materials: The “MultiMat-2” Experiment
Authors: Carra F , Accettura C , Bertarelli A , Berthomé E , Bruce R , Charitonidis N , Dalemir M , Farina E , Valenzuela J Guardia , Guinchard M , Lechner A , Nuiry F-X , Marcone A Perillo , Pfeiffer S , Glaude D , Rigutto E , Sacristan de Frutos O , Simon P , Redaelli S , Perez-Fontenla A T , Vollenberg W
Published: January 2024

In 2017, a proton-impact test on HL-LHC collimator materials was carried out in the HiRadMat facility at CERN. The experiment, called “MultiMat”, enabled the testing of uncoated and coated material composites and alloys, in most of the cases developed at CERN, for different beam collimation functionalities. Manufacturing of these materials was then passed to industry, leading to a series production for use in the collimators installed in the LHC during Long Shutdown 2 (LS2). The industrial versions of bulk and coating materials were tested in HiRadMat in 2021 in the “MultiMat-2” experiment, that efficiently re-used the same experimental test bench as for “MultiMat”. This new experiment demonstrated the reliability of the absorbers installed in LS2, and confirmed the possible use of alternative materials and coatings for the next LS3 collimator production. This paper describes the preparation and beam parameters of “MultiMat-2”, the experimental setup and the main results of the experiment.
Overview of material choices for HL-LHC collimators
Authors: Accettura C. , Biancacci N. , Bruce R. , Carra F. , Mounet N. , Kurtulus A. , Nuiry F.-X. , Marcone A. Perillo , Redaelli S.
Published: January 2024

In view of the High-Luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN, different materials were investigated for the upgrade of the LHC collimation system. A key objective was to determine how the jaws of the new collimators could be manufactured to meet the demanding requirements of HL-LHC, such as thermo-mechanical robustness and stability, beam coupling impedance, Ultra-High Vacuum (UHV), etc. During the Long-Shutdown 2 (LS2), five primary and ten secondary low-impedance collimators were already produced using novel materials. For LS3, in addition to more secondary collimators, the production and installation of other types of devices, including tertiaries and physics-debris collimators, is planned. This paper details the final mate-rial choices and rationale for each collimator family.
Progress Toward TURBO: A Novel Beam Delivery System for Charged Particle Therapy
Authors: Yap J SL , Steinberg A F , Clarke S J , Norman H XQ , Appleby R B , Sheehy S L
Published: January 2024

TURBO – Technology for Ultra Rapid Beam Operation – is a novel beam delivery system (BDS) in development at the University of Melbourne. The BDS determines several aspects of treatment delivery where a key bottleneck is the deadtime associated with beam energy variation. Beamlines at treatment facilities have a ±1% momentum acceptance range, requiring all the magnetic fields to adjust to deliver different energy beams at multiple depths in the tumour volume. A BDS using Fixed Field Alternating Gradient (FFA) optics could reduce the energy layer switching time (ELST) by enabling the transport of a large range of beam energies within the same fixed fields. We present recent progress and ongoing developments with TURBO, a proof-of-concept demonstrator adapted for low energy protons. Characterisation measurements were performed to determine realistic parameters for beam transport and particle tracking modelling. Simulation and experimental studies are shown for an energy degrader. We mention considerations of canted-cosine-theta magnets and further work to explore the clinical feasibility of a scaled-up BDS for charged particle therapy.
Overview of FLASHlab@PITZ: the new R&D platform for FLASH radiation therapy and radiation biology
Authors: Li X.-K. , Amirkhanyan Z. , Aftab N. , Boonpornprasert P. , Dmytriiev D. , Frohme M. , Georgiev G. , Grebinyk A. , Gross M. , Hoffmann A. , Komar Y. , Krasilnikov M. , Loisch G. , Oppelt A. , Richard C. , Riemer F. , Philipp S. , Schmitz M. , Müller F. , Obier F. , Vashchenko G. , Worm S. , Stephan F.
Published: January 2024

An R&D platform for electron FLASH radiation therapy and radiation biology is being prepared at the Photo Injector Test facility at DESY in Zeuthen (FLASHlab@PITZ). This platform is based on the unique beam parameters available at PITZ: ps scale electron bunches of up to 22 MeV with up to 5 nC bunch charge at MHz bunch repetition rate in bunch trains of up to 1 ms in length repeating at 1 to 10 Hz. It works together with the Technical University of Applied Sciences Wildau (TH Wildau) as partner in close vicinity for the biological resources.

A startup beamline has been installed to allow dosimetry studies and irradiation experiments on chemical, biochemical and biological samples after a 60-degree dispersive arm. The measured dose and dose rates under different beam conditions and first experimental results will be reported in this paper. In addition, a dedicated beamline for FLASHlab@PITZhas been designed for better control of the high brightness electron beams. This includes a dogleg to translate the beam and a 2D kicker system to scan the tiny beam focused by quadrupoles across the samples within less than 1 ms. Simulation studies will be presented to demonstrate the extremely flexible dose parameters with various irradiation options for electron FLASH radiation therapy and radiation biology studies.
A beam line setup for flash radiation therapy with focused electron beams at the PITZ facility at desy in zeuthen: Basic concept and dosimetry simulations
Authors: Amirkhanyan Z. , Aboulbanine Z. , Grebinyk A. , Gross M. , Krasilnikov M. , Kuhl T. , Li X.-K. , Oppelt A. , Philipp S. , Richard C. , Riemer F. , Stephan F. , Khachatryan V.
Published: January 2024

The objective of this study is demonstration of the principal possibility to increase the electron beam dose deposition at the certain depth of the sample for radiation therapy purposes. Electron bunches of 22 MeV within train generated at PITZ are focused inside the sample using a dedicated fast deflector and a solenoid magnet. To explore the capabilities of the proposed setup, dose distributions are calculated for multiple electron bunches focused in a single point inside a water phantom. Electron beam focusing produces dose peaks with a tunable maximal dose depth which is interesting for healthy tissue sparing at the surface and enhancing treatment quality. The duration of the full bunch train is 1 ms. During this time interval, the FLASH effect could be efficiently triggered inside the irradiated target volume. Monte Carlo simulations based on the FLUKA code were performed to evaluate the depth dose curves distributions in a water phantom. Using the PITZ electron beam parameters, simulations have shown the possibility to produce a peak dose in water seven times higher than compared to the dose at the surface. Moreover, the RMS size homogeneous area around the maximal dose is approximately 25 mm.
Conceptual design of the high-power electron beam irradiator using niobium-tin superconducting cavity
Authors: Sakai H , Yamamoto M , Tanaka O , Honda Y , Umemori K , Yamada T , Shimizu H , Morikawa Y , Kamiya Y , Nakamura N , Harada K , Higashi N
Published: January 2024

In recent years, there has been an increasing demand for high-intensity beams in the field of electron beam irradiation. This includes mass production of nuclear medicine examinations using 99Mo and high-efficiency production through material modification via material irradiation. Although superconducting cavities can achieve high-current beam acceleration, a compact accelerator is desirable for general-purpose irradiation beams. In this paper, we designed a practical 10 MeV, 50 mA high-current beam irradiator using a new Nb3Sn superconducting cavity.
Magnetic field simulations and measurements on the mini-ICAL detector
Authors: Khindri Honey , Satyanarayana B. , Indumathi D. , Datar V.M. , Shinde R. , Dalal N. , Prabhakar S. , Ajith S.
Published: January 2024

The ICAL (Iron Calorimeter) is a 51 kton magnetized
detector proposed by the INO collaboration. It is designed to detect
muons with energies in the 1–20 GeV range. A magnetic field of
∼ 1.5 T in the ICAL detector will be generated by passing a DC
current through suitable copper coils. This will enable it to
distinguish between μ- and μ+ that will be generated from
the interaction of atmospheric νμ and νμ
with iron. This will help in resolving the open question of mass
ordering in the neutrino sector. Apart from charge identification,
the magnetic field will be used to reconstruct the muon momentum
(direction and magnitude). Therefore it is important to know the
magnetic field in the detector as accurately as possible. We present
here an (indirect) measurement of the magnetic field in the 85 ton
prototype mini-ICAL detector working in Madurai, Tamil Nadu, for
different coil currents. A detailed 3-D finite element simulation
was done for the mini-ICAL geometry using Infolytica MagNet software
and the magnetic field was computed for different coil
currents. This paper presents, for the first time, a comparison of
the magnetic field measured in the air gaps with the simulated
magnetic field, to validate the simulation using real time
data. Using the simulations the magnetic field inside the iron is
estimated.
Exciton-carrier coupling in a metal halide perovskite nanocrystal assembly probed by two-dimensional coherent spectroscopy
Authors: Rojas-Gatjens Esteban , Otto Tiede David , Koch Katherine A , Romero-Perez Carlos , Galisteo-López Juan F , Calvo Mauricio E , Míguez Hernán , Srimath Kandada Ajay Ram
Published: January 2024

The surface chemistry and inter-connectivity within perovskite nanocrystals play a critical role in determining the electronic interactions. They manifest in the Coulomb screening of electron–hole correlations and the carrier relaxation dynamics, among other many-body processes. Here, we characterize the coupling between the exciton and free carrier states close to the band-edge in a ligand-free formamidinium lead bromide nanocrystal assembly via two-dimensional coherent spectroscopy. The optical signatures observed in this work show: (i) a nonlinear spectral lineshape reminiscent of Fano-like interference that evidences the coupling between discrete electronic states and a continuum, (ii) symmetric excited state absorption cross-peaks that suggest the existence of a coupled exciton-carrier excited state, and (iii) ultrafast carrier thermalization and exciton formation. Our results highlight the presence of coherent coupling between exciton and free carriers, particularly in the sub-100 femtosecond timescales.
An open-source robust machine learning platform for real-time detection and classification of 2D material flakes
Authors: Uslu Jan-Lucas , Ouaj Taoufiq , Tebbe David , Nekrasov Alexey , Bertram Jo Henri , Schütte Marc , Watanabe Kenji , Taniguchi Takashi , Beschoten Bernd , Waldecker Lutz , Stampfer Christoph
Published: January 2024

The most widely used method for obtaining high-quality two-dimensional (2D) materials is through mechanical exfoliation of bulk crystals. Manual identification of suitable flakes from the resulting random distribution of crystal thicknesses and sizes on a substrate is a time-consuming, tedious task. Here, we present a platform for fully automated scanning, detection, and classification of 2D materials, the source code of which we make openly available. Our platform is designed to be accurate, reliable, fast, and versatile in integrating new materials, making it suitable for everyday laboratory work. The implementation allows fully automated scanning and analysis of wafers with an average inference time of 100 ms for images of 2.3 Mpixels. The developed detection algorithm is based on a combination of the flakes’ optical contrast toward the substrate and their geometric shape. We demonstrate that it is able to detect the majority of exfoliated flakes of various materials, with an average recall (AR50) between 67% and 89%. We also show that the algorithm can be trained with as few as five flakes of a given material, which we demonstrate for the examples of few-layer graphene, WSe2, MoSe2, CrI3, 1T-TaS2 and hexagonal BN. Our platform has been tested over a two-year period, during which more than 106 images of multiple different materials were acquired by over 30 individual researchers.
3D printed modular Bouligand dissipative structures with adjustable mechanical properties for gradient energy absorbing
Authors: Xiao Junfeng , Zhang Mengxing , Zhai Fei , Wei Hongrui , Liu Sen , Wang Peng , Liu Zhiyang , Ji Zhongying , Wang Xiaolong
Published: January 2024

Three-dimensional (3D) printing allows for the creation of complex, layered structures with precise micro and macro architectures that are not achievable through traditional methods. By designing 3D structures with geometric precision, it is possible to achieve selective regulation of mechanical properties, enabling efficient dissipation of mechanical energy. In this study, a series of modular samples inspired by the Bouligand structure were designed and produced using a direct ink writing system, along with a classical printable polydimethylsiloxane ink. By altering the angles of filaments in adjacent layers (from 30° to 90°) and the filament spacing during printing (from 0.8 mm to 2.4 mm), the mechanical properties of these modular samples can be adjusted. Compression mechanical testing revealed that the 3D printed modular Bouligand structures exhibit stress-strain responses that enable multiple adjustments of the elastic modulus from 0.06 MPa to over 0.8 MPa. The mechanical properties were adjusted more than 10 times in printed samples prepared using uniform materials. The gradient control mechanism of mechanical properties during this process was analyzed using finite element analysis. Finally, 3D printed customized modular Bouligand structures can be assembled to create an array with Bouligand structures displaying various orientations and interlayer details tailored to specific requirements. By decomposing the original Bouligand structure and then assembling the modular samples into a specialized array, this research aims to provide parameters for achieving gradient energy absorption structures through modular 3D printing.
Stability of resonances for the Dirac operator
Authors: Mokeev D.
Published: January 2024

The Dirac operator on the semi-axis with a compactly supported potential is investigated. Let

(

k
n

)

n
≥
1

(k_n)_{n\geq 1}

be the sequence of its resonances, taken with multiplicities and ordered so that

|

k
n

|

|k_n|

do not decrease as

n
n

grows. It is proved that for any sequence

(

r
n

)

n
≥
1

∈

ℓ
1

(r_n)_{n\geq 1} \in \ell ^1

such that the points

k
n

+

r
n

k_n + r_n

remain in the lower half-plane for all

n
≥
1

n\geq 1

, the sequence

(

k
n

+

r
n

)

n
≥
1

(k_n + r_n)_{n\geq 1}

is also a sequence of resonances of a similar operator. Moreover, it is shown that the potential of the Dirac operator changes continuously under such perturbations.
Weighted CLR type bounds in two dimensions
Authors: Frank Rupert , Laptev Ari , Read Larry
Published: January 2024

We derive weighted versions of the Cwikel–Lieb–Rozenblum inequality for the Schrödinger operator in two dimensions with a nontrivial Aharonov–Bohm magnetic field. Our bounds capture the optimal dependence on the flux and we identify a class of long-range potentials that saturate our bounds in the strong coupling limit. We also extend our analysis to the two-dimensional Schrödinger operator acting on antisymmetric functions and obtain similar results.
YACHT: an ANI-based statistical test to detect microbial presence/absence in a metagenomic sample
Authors: Koslicki David , White Stephen , Ma Chunyu , Novikov Alexei
Published: January 2024

Motivation

In metagenomics, the study of environmentally associated microbial communities from their sampled DNA, one of the most fundamental computational tasks is that of determining which genomes from a reference database are present or absent in a given sample metagenome. Existing tools generally return point estimates, with no associated confidence or uncertainty associated with it. This has led to practitioners experiencing difficulty when interpreting the results from these tools, particularly for low-abundance organisms as these often reside in the “noisy tail” of incorrect predictions. Furthermore, few tools account for the fact that reference databases are often incomplete and rarely, if ever, contain exact replicas of genomes present in an environmentally derived metagenome.

Results

We present solutions for these issues by introducing the algorithm YACHT: Yes/No Answers to Community membership via Hypothesis Testing. This approach introduces a statistical framework that accounts for sequence divergence between the reference and sample genomes, in terms of ANI, as well as incomplete sequencing depth, thus providing a hypothesis test for determining the presence or absence of a reference genome in a sample. After introducing our approach, we quantify its statistical power and how this changes with varying parameters. Subsequently, we perform extensive experiments using both simulated and real data to confirm the accuracy and scalability of this approach.

Availability and implementation

The source code implementing this approach is available via Conda and at https://github.com/KoslickiLab/YACHT. We also provide the code for reproducing experiments at https://github.com/KoslickiLab/YACHT-reproducibles.
Accuracy of point-of-care testing devices for haemoglobin in the operating room: meta-analysis
Authors: Ahn Hilalion (San) , Lenet Tori , Gilbert Richard W D , Mallick Ranjeeta , Shaw Julie L V , Fergusson Dean A , McIsaac Daniel I , Martel Guillaume
Published: January 2024

Background

Point-of-care tests (POCT) for haemoglobin are increasingly used to guide intraoperative transfusion. However, their accuracy compared to central laboratory tests is unknown. The objective was to perform a systematic review and meta-analysis of method comparison studies assessing the accuracy of POCT versus central laboratory haemoglobin tests in patients undergoing surgery.

Methods

Electronic databases were searched from inception to April 2020 (updated August 2023). Any methodological approach comparing haemoglobin measurements between POCT and central laboratory in patients undergoing surgery under anaesthesia in the operating room were included. Data abstraction was guided by PRISMA and risk of bias was assessed by QUADAS-2. Data were extracted independently and in duplicate by two reviewers. Outcomes included mean differences between POCT and central laboratory haemoglobin with associated standard deviations and 95% limits of agreement (LOA).

Results

Of 3057 citations, 34 studies were included (n = 2427, 6857 paired measurements). Several devices were compared (pulse co-oximetry, n = 25; HemoCue, n = 10; iSTAT, n = 6; blood gas analysers, n = 10; haematology analyser, n = 2). Median sample size was 41 patients, and 11 studies were funded by device manufacturers. Fifteen of 34 studies had low risk of bias. Pooled mean differences (95% LOA) were: pulse co-oximeters 2.3 g/l (−25.2–29.8), HemoCue −0.3 g/l (−11.1–10.5), iSTAT −0.3 g/l (−8.4–7.8) and blood gas analysers −2.6 g/l (−17.8–12.7).

Conclusion

All POCT examining intraoperative haemoglobin measurement yielded pooled mean difference LOAs larger than the allowable limit difference of ±4 g/dl. Intraoperative haemoglobin measured by POCT should not be considered interchangeable with central laboratory values and caution is necessary when using these tests to guide intraoperative transfusion.
Giant left sinus of Valsalva aneurysm as a rare cause of acute myocardial infarction: a case report
Authors: Maqableh Ghaith M , Yuan Mengshi , Moody William , Baig Shanat , Khan Sohail Q
Published: January 2024

Background

Sinus of Valsalva aneurysm (SVA) is a rare but potentially life-threatening condition. Acute myocardial infarction (MI) is a rare consequence of aneurysmal dilatation of one or more sinuses of Valsalva. We present a case of an unruptured and partially thrombosed left SVA, presenting as anterior MI and congestive heart failure.

Case summary

A 55-year-old gentleman was admitted with pulmonary oedema and a late presenting ST-elevation MI with Q wave. After initial treatment on furosemide infusion, a coronary angiography showed significant stenosis in both his left main stem (LMS) and left anterior descending artery (LAD). This is likely a result of external compression, potentially from the enlarged left sinus of Valsalva. A subsequent transthoracic echocardiogram and transoesophageal echocardiogram (TOE) confirmed large SVA involving the left coronary cusp measured 9.9 cm compressing both LMS and LAD.

Discussion

Left SVAs are rare and frequently asymptomatic, typically being identified incidentally. Due to the close proximity of the left coronary system, they can present with myocardial ischaemia due to extrinsic compression of the coronary system. We were able to perform a comprehensive multi-modality assessment of left SVA, which helped establish this unusual diagnosis and guide management. Transthoracic echocardiogram and TOE helped assess the SVA and demonstrated the thrombus in situ, aortic valve insufficiency, and cardiac function. The computed tomography scan aided in accurately defining the extent of the aneurysm and the extent of compression of the left coronary system and cardiac magnetic resonance scan was able to demonstrate viability in LAD and circumflex territory.
Effects of albiglutide on myocardial infarction and ischaemic heart disease outcomes in patients with type 2 diabetes and cardiovascular disease in the Harmony Outcomes trial
Authors: Krychtiuk Konstantin A , Marquis-Gravel Guillaume , Murphy Shannon , Alexander Karen P , Chiswell Karen , Green Jennifer B , Leiter Lawrence A , Lopes Renato D , Del Prato Stefano , Jones William Schuyler , McMurray John J V , Hernandez Adrian F , Granger Christopher B
Published: January 2024

Aims

Large outcome trials have demonstrated cardiovascular benefits of selected glucagon-like peptide-1 (GLP-1) receptor agonists. We examined coronary disease outcomes in the Harmony Outcomes trial of the GLP-1 receptor agonist albiglutide.

Methods and results

Harmony Outcomes was an event-driven, multicenter, double-blind, and placebo-controlled trial involving 9463 patients >40 years of age with type-2 diabetes and established atherosclerotic cardiovascular disease. It tested the effects of albiglutide on the occurrence of a composite primary endpoint, consisting of cardiovascular death, myocardial infarction (MI), or stroke. Within this post-hoc analysis, the effects of albiglutide on MI subtypes and other ischaemic endpoints were analysed.

During the median-follow up of 1.6 years, a total of 421 patients (4.5%) experienced at least one MI, with 72 patients having more than one event. Treatment with albiglutide reduced both first events [hazard ratio (HR) 0.75 (0.62–0.91)] and overall events [HR 0.75 (0.61–0.91)] as well as first type 1 [HR 0.73 (0.57–0.92)] and type 2 myocardial infarctions [HR 0.65 (0.46–0.92)]. The effect of albiglutide treatment was consistent for ST-segment elevation [HR 0.69 (0.38–1.26)] and non-ST elevation (HR 0.86 (0.66–1.2) MI.

Conclusion

Treatment with the GLP-1 receptor agonist albiglutide resulted in a 25% relative risk reduction in MI that was consistent for type of infarction and presence or absence of ST elevation. Our findings add novel information about the effects of GLP-1 receptor agonists on ischaemic events in patients with type 2 diabetes.
Molecular magnetic resonance imaging of myeloperoxidase activity identifies culprit lesions and predicts future atherothrombosis
Authors: Nadel James , Wang Xiaoying , Saha Prakash , Bongers André , Tumanov Sergey , Giannotti Nicola , Chen Weiyu , Vigder Niv , Chowdhury Mohammed M , da Cruz Gastao Lima , Velasco Carlos , Prieto Claudia , Jabbour Andrew , Botnar René M , Stocker Roland , Phinikaridou Alkystis
Published: January 2024

Aims

Unstable atherosclerotic plaques have increased activity of myeloperoxidase (MPO). We examined whether molecular magnetic resonance imaging (MRI) of intraplaque MPO activity predicts future atherothrombosis in rabbits and correlates with ruptured human atheroma.

Methods and results

Plaque MPO activity was assessed in vivo in rabbits (n = 12) using the MPO-gadolinium (Gd) probe at 8 and 12 weeks after induction of atherosclerosis and before pharmacological triggering of atherothrombosis. Excised plaques were used to confirm MPO activity by liquid chromatography–tandem mass spectrometry (LC–MSMS) and to determine MPO distribution by histology. MPO activity was higher in plaques that caused post-trigger atherothrombosis than plaques that did not. Among the in vivo MRI metrics, the plaques’ R1 relaxation rate after administration of MPO-Gd was the best predictor of atherothrombosis. MPO activity measured in human carotid endarterectomy specimens (n = 30) by MPO-Gd–enhanced MRI was correlated with in vivo patient MRI and histological plaque phenotyping, as well as LC–MSMS. MPO-Gd retention measured as the change in R1 relaxation from baseline was significantly greater in histologic and MRI-graded American Heart Association (AHA) type VI than type III–V plaques. This association was confirmed by comparing AHA grade to MPO activity determined by LC–MSMS.

Conclusion

We show that elevated intraplaque MPO activity detected by molecular MRI employing MPO-Gd predicts future atherothrombosis in a rabbit model and detects ruptured human atheroma, strengthening the translational potential of this approach to prospectively detect high-risk atherosclerosis.
Genomic Data Reveal Diverse Biological Characteristics of Scleractinian Corals and Promote Effective Coral Reef Conservation
Authors: Shinzato Chuya , Yoshioka Yuki
Published: January 2024

Reef-building corals (Scleractinia, Anthozoa, Cnidaria) are the keystone organisms of coral reefs, which constitute the most diverse marine ecosystems. Since the first decoded coral genome reported in 2011, about 40 reference genomes are registered as of 2023. Comparative genomic analyses of coral genomes have revealed genomic characters that may underlie unique biological characteristics and coral diversification. These include existence of genes for biosynthesis of mycosporine-like amino acids, loss of an enzyme necessary for cysteine biosynthesis in family Acroporidae, and lineage-specific gene expansions of DMSP lyase-like genes in the genus Acropora. While symbiosis with endosymbiotic photosynthetic dinoflagellates is a common biological feature among reef-building corals, genes associated with the intricate symbiotic relationship encompass not only those shared by many coral species, but also genes that were uniquely duplicated in each coral lineage, suggesting diversified molecular mechanisms of coral-algal symbiosis. Coral genomic data have also enabled detection of hidden, complex population structures of corals, indicating the need for species-specific, local-scale, carefully considered conservation policies for effective maintenance of corals. Consequently, accumulating coral genomic data from a wide range of taxa and from individuals of a species not only promotes deeper understanding of coral reef biodiversity, but also promotes appropriate and effective coral reef conservation. Considering the diverse biological traits of different coral species and accurately understanding population structure and genetic diversity revealed by coral genomic analyses during coral reef restoration planning could enable us to “archive” coral reef environments that are nearly identical to natural coral reefs.
Exome-Wide Sequencing Study Identified Genetic Variants Associated With Sarcopenic Obesity
Authors: Xu Qian , Zhao Qi-Gang , Ma Xin-Ling , Yan Shan-Shan , Han Bai-Xue , Song Zi-Tong , Bu Fan , Li Kuan , Zhang Lei , Pei Yu-Fang
Published: January 2024

Sarcopenic obesity (SO) is an age-related disease characterized by the coexistence of excessive adiposity and low muscle mass or function. Although obesity and sarcopenia are heritable conditions, the genetic determinants of SO have not been fully understood. We conducted a large-scale exome-wide association analysis of SO in a sequenced sample of 2 887 cases and 113 284 controls and an imputed sample of 4 003 cases and 161 990 controls in the UK Biobank cohort. Single-variant association analysis identified one locus 1q41 (lead SNP rs1417066, LYPLAL1-AS1, odds ratio [OR] = 1.15, 95% confidence interval [CI] = [1.11–1.19], p = 1.75 × 10−14) that was significantly associated with SO at the exome-wide significance level (p < 1 × 10-8). Colocalization analysis in the Genotype-Tissue Expression expression quantitative trait locus database showed that LYPLAL1-AS1 was colocalized with SO in multiple musculoskeletal-related tissues. Gene-based burden test of rare loss-of-function variants identified 5 genes at the gene-wise significance level (p < 4.3 × 10−6): PDE3B (OR = 2.48, p = 1.10 × 10−6), MYOZ3 (OR = 25.49, p = 1.41 × 10−7), SLC15A3 (OR = 4.75, p = 6.82 × 10−7), RNF130 (OR = 25.83, p = 4.07 × 10−6), and TNK2 (OR = 4.25, p = 8.75 × 10−8). Overall, our study uncovered the genetic effects of both common and rare variants on SO susceptibility, expanded existing knowledge of the genetic architecture of SO, and improved understanding of the genetic mechanisms underlying SO.
Mental Health Impacts of COVID-19: Does Prepandemic Cognition and Dementia Status Matter?
Authors: Nichols Emma , Petrosyan Sarah , Lee Jinkook
Published: January 2024

Background

The coronavirus disease 2019 (COVID-19) pandemic disrupted daily life and led to sharp shocks in trends for various health outcomes. Although substantial evidence exists linking the pandemic and mental health outcomes and linking dementia and mental health outcomes, little evidence exists on how cognitive status may alter the impact of COVID-19 on mental health.

Methods

We used prepandemic data from the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia study and 9 waves of data from the Real-Time Insights of COVID-19 in India study (N = 1 182). We estimated associations between measures of prepandemic cognition (continuous cognition based on 22 cognitive tests, dementia status) and mental health measures during the pandemic (Patient Health Questionnaire [PHQ]-4 [9 time points], PHQ-9 [2 time points], Beck Anxiety Inventory [3 time points]), adjusting for age, gender, rural/urban residence, state, education, and prepandemic mental health.

Results

Summarizing across time points, PHQ-9 score was marginally or significantly associated with prepandemic cognition (PHQ-9 difference: −0.38 [−0.78 to 0.14] points per SD higher cognition; p = .06), and prepandemic dementia (PHQ-9 difference: 0.61 [0.11–1.13] points for those with dementia compared to no dementia; p = .02). Associations with BAI were null, whereas associations with PHQ-4 varied over time (p value for interaction = .02) and were strongest during the delta wave, when pandemic burden was highest.

Conclusions

We present initial evidence that mental health impacts of COVID-19 or other acute stressors may be unequally distributed across strata of cognitive outcomes. In dynamically changing environments, those with cognitive impairment or dementia may be more vulnerable to adverse mental health outcomes.
Sensory Health Among Older Adults in the United States: A Neighborhood Context Approach
Authors: Goldman Alyssa W , Pinto Jayant M
Published: January 2024

Objectives

Sensory health declines with age but remains critical to the navigation and enjoyment of everyday life. Neighborhoods are key sites of environmental exposure, social engagement, and access to resources that can shape sensory health, yet the residential neighborhood is understudied as a determinant of sensory function.

Methods

We use data from Rounds 1 and 2 of the National Social Life, Health, and Aging Project to examine how subjective and objective measures of older adults’ residential areas are associated with sensory health in a series of cross-sectional and multilevel regression models.

Results

In cross-sectional models, higher levels of perceived neighborhood social ties are associated with significantly better self-rated vision. Older adults who reside in more densely populated tracts are more likely to have significantly worse olfactory identification, whereas residing in tracts with higher levels of concentrated disadvantage is associated with significantly lower levels of self-rated vision. In multilevel models, residing in more densely populated tracts is associated with significantly worse olfactory identification, whereas tract-level concentrated disadvantage is associated with significantly worse hearing and vision.

Discussion

We propose that neighborhood characteristics could influence certain environmental exposures, the amount of time that older adults spend out of the home, patterns of social engagement, and access to preventative care that collectively affect sensory health. Residential neighborhoods may be important sites of potential intervention to slow age-related sensory declines and other related conditions.
Infant mortality in Ghana: investing in health care infrastructure and systems
Authors: Poulin Danielle , Nimo Gloria , Royal Dorian , Joseph Paule Valery , Nimo Tiffany , Nimo Tyra , Sarkodee Kofi , Attipoe-Dorcoo Sharon
Published: January 2024

Child and infant mortality is a global problem. Almost half of deaths of children under age 5 years occur in the neonatal period, the first 28 days of life, with 2.4 million neonatal deaths globally in 2020. Sub-Saharan Africa has disproportionately high numbers of neonatal deaths. Ghana's neonatal mortality rate is 22.8 per 1000 live births and remains behind targets set by the United Nations Sustainable Development Goals. Quality antenatal care, postnatal monitoring, breastfeeding support, and postnatal family planning are important in preventing neonatal deaths. While Ghana has made progress in making care more financially accessible, it has not been matched with the improvements in the critical infrastructure required to ensure quality health care. The improvements have also not eliminated out-of-pocket costs for care, which have hindered progress in decreasing infant mortality. Policymakers should consider investments in health care infrastructure, including expanding public–private partnerships. Policies that improve workforce development programs, transportation infrastructure, and health insurance systems improvements are needed.
Determination of Acrylamide in Coffee, Cereals, Baby Food, Cocoa, Dry Pet Food, Potato Products, Vegetable Crisps, Biscuits, Tea, Nuts, and Spices by LC-MS/MS in a Single-Laboratory Validation: First Action 2023.01
Authors: Bebius Aude , Reding Frédérique , Theurillat Viviane , Valérie Leloup , Konings Erik , Delatour Thierry , Desmarchelier Aurélien
Published: January 2024

Background

Acrylamide (AA) is a process contaminant naturally formed during the cooking of starchy food at high temperatures. Considering existing risks of misquantification inherent to the analysis of AA, an AOAC initiative raised the need for a consensus standard to determine AA in a broad variety of food.

Objective

A quantitative LC-MS/MS method for AA determination in food was validated in a single-laboratory study. Targeted performance requirements in terms of target matrixes, limit of quantification, recovery, and precision were as defined per Standard Method Performance Requirement (SMPR®) 2022.006.

Method

The proposed method derives from EN 16618:2015 standard pending modifications brought to the (1) sample preparation (simplified, potentially automated); (2) scope of application (significantly extended); and (3) LC conditions (improved selectivity). Confirmatory detection of AA is conducted by LC-MS/MS in the Selected Reaction Monitoring mode (SRM), and isotopic dilution was applied for quantification approach using either 2,3,3-d3-acrylamide (d3-AA), or 13C3-2,3,3-d3-acrylamide (13C3-d3-AA) as labeled internal standard.

Results

A total of 16 laboratory samples from nine matrix categories were included in the validation process. A full validation was conducted on coffee (instant, roast), infant cereal, cocoa powder, pet food (croquettes), tea (green tea), spices (black pepper), and nuts (roasted almonds) with satisfactory performances both in terms of recovery (97–108%) and precision (RSDr and RSDiR <12%). The method applicability was further demonstrated through the analysis of quality control materials and reference materials including French fries, potato crisps, vegetable crisps, instant coffee, infant food, and biscuits (cookies), with accuracy values determined within a 94–107% range.

Conclusions

The performances of the presented method are in agreement with the acceptance criteria stipulated in SMPR 2022.006.

Highlights

The Expert Review Panel for acrylamide approved the present method as AOAC Official First Action 2023.01.
A Comparison of Teleburn to In-Person Consultation of Pediatric Patients in a Children’s Emergency Department
Authors: Ayers Claci , Byrd Hannah , Kidd Rebecca , Solomon Barbara , Gondek Stephen , Wagner Anne , Mubang Ronnie
Published: January 2024

Pediatric burn care is an essential component of emergency care and there are disparities in access to regional burn centers. Teleburn is a tool that enables providers without a certified burn center to provide photos of a burn to experts and receive recommendations. The purpose of this study is to evaluate the effectiveness of a Teleburn system to the in-person consultation regarding burn infection rate, clinic follow-up rate, postburn admission rate, and 72-h bounce back rate.

Data were collected from December 2019 to March 2022 through the electronic medical record. A total of 416 patient encounters that met the criteria were analyzed. A non-inferiority study was designed comparing proportional outcomes of Teleburn initial visits to emergency department visits regarding burn infection rate, clinic follow-up rate, postburn admission rate, and 72-h bounce back rate. The data were compared with a difference of greater than 10% being considered inferior.

No differences were identified in rates of readmission—1.67% difference (95% CI −27%< x < 23.8%) and return within 72 h—0.7% difference (−18.4%< x < 19.7%). Teleburn patients were 12.6% less likely to follow-up (2.7%< x < 22.40%). Only one infection was identified, which was insufficient to conclude non-inferiority.

While convenient, Teleburn consult could not be demonstrated to be non-inferior to in-person consultation. No differences in infection rates were identified, and differences in readmission and return were clinically insignificant. This study demonstrates that Teleburn may be effective and feasible for regional burn centers if follow-up can be improved.