bluuebunny/crossref_metadata_2025 huggingface dataset:
An effective self-collision detection algorithm for multi-degree-of-freedom manipulator
Authors: Liu Zhenyu , Zhang Lianhao , Qin Xiaohong , Li Gang
Published: October 2022

In order to address the self-collision problem associated with the operation of modern industrial robots, this paper proposes a multi-degree-of-freedom collision detection algorithm that can detect self-collision in single arm and double arm robots as well as collision with the load. Firstly, the zero pose of the Denaviti−Hartenberg model is built based on the manipulator configuration, and the coordinate information of each key point is obtained through a rotation and translation operation of the matrix. Then, the positional relation and distance between the detected objects are determined by the spatial geometry theory, and finally, collision is detected using a collision matrix. By simulating two groups of single arms and two groups of double arms, and from the laboratory testing of SR10C in the SIASUN robot factory, it has been verified that the proposed algorithm has good collision detection capability. Without the use of sensors, cameras, and other external devices, the collision between the arm and the load, and the collision between the cooperative robot and the load may be effectively detected and mitigated.
Assessment of incident power density in different shapes of averaging area for radio-frequency exposure above 6 GHz
Authors: Morimoto Ryota , Hirata Akimasa
Published: October 2022

Objective. The International Commission on Non-Ionizing Radiation Protection guidelines and IEEE C95.1-2019 standard for human protection from local electromagnetic field exposure above 6 GHz state that absorbed (or epithelial) power density (APD) and incident power density (IPD), averaged over a square area, are internal and external physical quantities, respectively, that set the exposure limit. Per exposure standards, the measurement procedure and evaluation of the IPD have been established in technical standards, where a circular averaging area is recommended only for non-planar surfaces in IEC/IEEE 63195-1 and -2. In this study, the effects of two averaging shapes on the APD and IPD are evaluated computationally to provide new insights from the viewpoint of exposure standards. Approach. The relation between the APD, IPD, and the steady-state temperature rise (heating factor) in rectangular and human models for exposure to a single dipole, dipole arrays, and the Gaussian beams is investigated computationally with finite-difference method. Main results. The maximum differences in the heating factor of the APD and IPD for square and circular averaging areas were 4.1% and 4.4% for the antenna–model distance >5 mm, respectively. These differences appear when the beam pattern on the model surface has an elliptical shape. For an antenna–model distance ≤5 mm and at frequencies ≤15 GHz, the heating factors for square averaging areas were not always conservative to those for circular ones (−7.8% for IPD), where only the antenna feed point are visible before beam formation. Significance. The heating factors of the APD and IPD for a circular averaging area are conservative for near-field exposure of canonical sources for frequencies up to 300 GHz, except for a beam with a significant major-to-minor axis ratio and an angle of 30°–60° to a square averaging area. This tendency would help bridge the gap between exposure and product standards.
A clinically relevant online patient QA solution with daily CT scans and EPID-based in vivo dosimetry: a feasibility study on rectal cancer
Authors: Chen Liyuan , Zhang Zhiyuan , Yu Lei , Peng Jiyou , Feng Bin , Zhao Jun , Liu Yanfang , Xia Fan , Zhang Zhen , Hu Weigang , Wang Jiazhou
Published: October 2022

Objective. Adaptive radiation therapy (ART) could protect organs at risk (OARs) while maintain high dose coverage to targets. However, there is still a lack of efficient online patient quality assurance (QA) methods, which is an obstacle to large-scale adoption of ART. We aim to develop a clinically relevant online patient QA solution for ART using daily CT scans and EPID-based in vivo dosimetry. Approach. Ten patients with rectal cancer at our center were included. Patients’ daily CT scans and portal images were collected to generate reconstructed 3D dose distributions. Contours of targets and OARs were recontoured on these daily CT scans by a clinician or an auto-segmentation algorithm, then dose-volume indices were calculated, and the percent deviation of these indices to their original plans were determined. This deviation was regarded as the metric for clinically relevant patient QA. The tolerance level was obtained using a 95% confidence interval of the QA metric distribution. These deviations could be further divided into anatomically relevant or delivery relevant indicators for error source analysis. Finally, our QA solution was validated on an additional six clinical patients. Main results. In rectal cancer, the 95% confidence intervals of the QA metric for PTV ΔD
95 (%) were [−3.11%, 2.35%], and for PTV ΔD
2 (%) were [−0.78%, 3.23%]. In validation, 68% for PTV ΔD
95 (%), and 79% for PTV ΔD
2 (%) of the 28 fractions are within tolerances of the QA metrics. one patient’s dosimetric impact of anatomical variations during treatment were observed through the source of error analysis. Significance. The online patient QA solution using daily CT scans and EPID-based in vivo dosimetry is clinically feasible. Source of error analysis has the potential for distinguishing sources of error and guiding ART for future treatments.
Advances in Magnum-PSI probe diagnosis in support of plasma–surface interaction studies
Authors: Costin C , Mihaila I , van der Meiden H J , Scholten J , van Eck H J N , Vernimmen J W M
Published: October 2022

Magnum-PSI is a linear plasma generator equipped with a superconducting magnet, assuring fusion devices relevant conditions at plasma–surface interface. The plasma column was diagnosed using 64 probes embedded in the target. The cross-sectional distributions of plasma parameters (floating potential, ion saturation current and electron temperature) were measured for hydrogen and deuterium plasmas under various discharge conditions. The radial profile of the floating potential across the plasma column can be described by a reversed Mexican hat-like wavelet, having the most negative potential at the center of the plasma column. The negativity of the floating potential diminishes when the discharge current increases or the magnetic field decreases. The axial gradient of the floating potential is reduced by increasing the magnetic field. The ion saturation current is maximum at the center of the plasma column, increasing with both the discharge current and magnetic field. The ion flux to the target, estimated from Thomson scattering (TS) data, was confirmed by probe measurements. The electron temperature estimated from the ion branch of the probe current–voltage characteristic is few times larger than that obtained from TS. By increasing the gas pressure in the target chamber, the time-dependent ion saturation current measured by probes changes from a constant average current (when the plasma column is attached to the target) to a fluctuating average current with scattered peaks (in a partially detached regime) which vanishes completely in the fully detached regime. With respect to hydrogen, the plasma column is wider in deuterium and is characterized by less negative floating potential distributions.
Design and performance research on the actuator of high-speed valve based on shear working mode of magnetorheological fluid
Authors: Dai Jin , Yang Chenghao , Feng Xiangyu , Xiong Shaoping
Published: October 2022

The high-speed valve with advanced performance, which is expected to possess characteristics of large nominal flow and fast response at the same time, plays an important role in enabling efficient digital hydraulics. In order to solve the tradeoff between a large rated flow and less response time, this paper proposed a novel design of high-speed valve actuator called energy coupler actuator (ECA) based on the shear working mode of magnetorheological fluid. The ECA allows a rotary energy source couple/decouple the translational valve spool for fast and long stroke on/off switching. This work developed a multi-physics model of ECA to study its performance and simulation work based on response surface method has been conducted to optimize the ECA design parameters. An ECA prototype with the optimal design solution has been manufactured and experimentally tested. The testing results shows that driven by the power level similar to off-the-shelf solenoid valves, this ECA prototype only took 5 ms to achieve 1.5 mm stroke, which provide a flow area equivalent to a nominal flow of 100 l min−1@5 bar. This prototype also demonstrated the ECA’s design feature of long stroke with quick response by achieving 7 mm stroke in just 16 ms.
Cosmic perturbations from a rotating field
Authors: Co Raymond T. , Harigaya Keisuke , Pierce Aaron
Published: October 2022

Complex scalar fields charged under approximate U(1) symmetries appear in well-motivated extensions of the Standard Model. One example is the field that contains the QCD axion field associated with the Peccei-Quinn symmetry; others include flat directions in supersymmetric theories with baryon, lepton, or flavor charges. These fields may take on large values and rotate in field space in the early universe. The relevant approximate U(1) symmetry ensures that the angular direction of the complex field is light during inflation and that the rotation is thermodynamically stable and is long-lived. These properties allow rotating complex scalar fields to naturally serve as curvatons and explain the observed perturbations of the universe. The scenario imprints non-Gaussianity in the curvature perturbations, likely at a level detectable in future large scale structure observations. The rotation can also explain the baryon asymmetry of the universe without producing excessive isocurvature perturbations.
Dynamical adaptation in photoreceptors with gain control
Authors: Castillo García Miguel , Urdapilleta Eugenio
Published: October 2022

The retina hosts all processes needed to convert external visual stimuli into a neural code. Light phototransduction and its conversion into an electrical signal involve biochemical cascades, ionic regulations, and different kinds of coupling, among other relevant processes. These create a nonlinear processing scheme and light-dependent adaptive responses. The dynamical adaptation model formulated in recent years is an excellent phenomenological candidate to resume all these phenomena into a single feedforward processing scheme. In this work, we analyze this description in highly nonlinear conditions and find that responses do not match those resulting from a very detailed microscopic model, developed to reproduce electrophysiological recordings on horizontal cells. When a delayed light-dependent gain factor incorporates into the description, responses are in excellent agreement, even when spanning several orders of magnitude in light intensity, contrast, and duration, for simple and complex stimuli. This extended model may be instrumental for studies of the retinal function, enabling the linking of the microscopic domain to the understanding of signal processing properties, and further incorporated in spatially extended retinal networks.
Investigating pair-production by Breit–Wheeler process in a collisional plasma
Authors: Malik Hitendra K , Punia Sheetal
Published: October 2022

Positrons have many potential applications in the field of high-energy nuclear and particle physics. For the generation of such high-energy positrons, we propose a mechanism via an interaction of optical vortex laser beams with collisional plasma. Based on the multiphoton Breit–Wheeler mechanism, the production of electron–positron pairs shows to be strongly dependent on the energy associated with the synchrotron radiation. Such radiations are emitted by accelerated charged particles in the plasma channel under quasistatic spontaneous magnetic field that confines the motion of the electrons. For the precise regulation of the accelerated positrons important quantities such as the probabilistic generation of positrons and the angular momentum of the plasma electrons are evaluated and discussed. It is observed that the use of the incident Laguerre–Gaussian laser beam helps to generate on-axis sheath formation to focus and accelerate the produced positrons.
Laser-assisted CP-odd and CP-even Higgs bosons production in THDM
Authors: Ouhammou M , Ouali M , Taj S , Benbrik R , Manaut B , Hrour E
Published: October 2022

In this paper, we have theoretically studied the neutral Higgs pair production in Two Higgs Doublet Model (THDM) in the presence of a circularly polarized laser field. The laser-assisted differential partial cross section is derived in the centre of mass frame at the leading order including Z diagram. The total cross section is computed numerically by integrating the differential cross section over the solid angle

d
Ω

. Two benchmark points are discussed for the THDM parameters. In the first step, we have analysed the total cross section of

e

+

e

−

→

h

0

A

0

by considering H
0 as the standard model (SM)-like Higgs boson. Then, the process

e

+

e

−

→

H

0

A

0

is studied by taking h
0 as the Higgs boson of the SM. For both benchmark points, the laser-assisted total cross section of the studied processes depends on the produced neutral Higgs masses, the centre of mass energy and the laser field parameters. In addition, the maximum cross section occurs at high centre of mass energy for the process

e

+

e

−

→

H

0

A

0

as compared to that of

e

+

e

−

→

h

0

A

0

.
A reduced model for the ITER divertor based on SOLPS solutions for ITER Q = 10 baseline conditions: B. A reduced model based on reversed-direction two point modeling
*
Authors: Stangeby P.C. , Lore J.D. , Pitts R.A. , Canik J.M. , Bonnin X.
Published: October 2022

Edge codes such as SOLPS coupled to neutral codes such as EIRENE have become so comprehensive and sophisticated that they now constitute, in effect, ‘code-experiments’ that, as for actual experiments, can benefit from interpretation using simple models and conceptual frameworks, i.e. reduced models. The first task is the identification of options for the reduced model control parameters that are best suited for control of the action of the divertor, i.e. for control of target power loading and sputter–erosion, primarily. A strong correlation between the electron temperature at the divertor target, T
e,t, and the neutral deuterium D2 density at the target, n
D2,t, flux-tube resolved, has recently been reported for a number of code studies including SOLPS-4.3 modeling of a set of ∼50 ITER baseline cases: Q
DT = 10, q
95 = 3, P
SOL = 100 MW, metallic walls, and Ne seeding (Pitts et al 2019). Part A of the present study reports new results for largely the same ITER cases, confirming the strong correlation reported earlier between local values of T
e,t, and (i) n
D2,t, and (ii) normalized volumetric losses of power and pressure in the divertor. Strong correlations have now also been found, and are reported here for the first time, between T
e,t and all of the divertor target quantities of practical interest. A physical explanation for this surprising result has not as yet been fully identified; nevertheless it has encouraging implications for reduced modeling of the ITER divertor. For such ITER conditions, (i) the global Ne injection rate, InjNe (Ne s−1), and (ii) the electron temperature at the location on the target where the peak power deposition occurs, T
e,t@q⊥,pk (eV), are found to be promising reduced model control parameters. In this part B, a reduced model for the ITER divertor is developed and described in detail, based on reversed-direction two point modeling, Rev2PM. The input to the reduced model is a value of the variable pair

T

e
,
t

@

q

⊥
,
p
k

,
I
n

j

Ne

for a chosen case and the output are values of the various target as well as divertor-entrance quantities of practical interest, e.g. q
⊥,pk, the electron density at the X-point, n
e,Xpt, etc. The reduced model was quantitatively characterized using one half of the code cases; it was then used to successfully predict (replicate) the code values of e.g. n
e,Xpt for the other half.
Safety Cost Estimation of Building Construction with Fuzzy Logic and Artificial Neural Network
Authors: Sari F A K , Latief Y
Published: October 2022

The number of cases of construction work accidents continues to increase every year. To prevent work accidents, especially the fatality rate, Occupational Health and Safety (OHS) must be implemented in the construction project. Implementation of OHS can be a success if the availability of the budget is allocated explicitly for implementing OHS in construction projects. However, respondents’ current OHS budget is currently insufficient when referring to the guidelines regarding OHS costs applied in Indonesia. This condition will increase the initial budget and cause financial losses. So it is necessary to develop a cost estimation model that can estimate costs quickly and accurately. The results from this study will help estimator make OHS cost estimates quickly and accurately so that an estimator does not need a long time to do cost estimations at the beginning of the project, and the results of the estimated cost estimates are accurate. The fuzzy method uses to classify the contract value. The output of the fuzzy process will use as input in learning with the neural network. The Mean Absolute Percentage Error of tested data set for the adapted model is highly accurate (9.906%). The model obtained has a better MAPE value than the estimated cost by using regression analysis.
Flotation of suspended solid by introducing coagulant and fine bubbles in the mobile wastewater treatment plant
Authors: Joni I Made , Sofia Dedeh Rosmaniar , Sulistio Eko , Azhary Sundoro Yoga , Wibawa Bambang Mukti , Panatarani Camellia
Published: October 2022

Turbidity is an essential process variable in water treatment processes for clean water. This study reports the development of a mobile mini wastewater treatment plant (WTTP) intended to provide clean water in flooding incidents, where access to clean water is demanding. The mobile mini-WTTP employed with a fine bubbles generator aims to provide micro and nano bubbles with longer residence in the water expected to promote an effective flotation process. The system was evaluated in removing suspended solid capability to reduce total suspended solids (TSS) or water turbidity. The system consists of a mesh trap, chemical flocculation, dissolved air flotation chamber, and activated carbon–zeolite as a mineral filter. The system was tested on the suspended solid from homogenized clay resulted from a turbid tap water effluent with adjusted turbidity up to 500 FNU on the storage tank. Alum solution with a dosage of 200 mg/L was used as a coagulant agent. In the flotation process was introduced a fine bubbles generator with a pressurized mechanism. The effluent was pumped from a storage tank into a treatment plant with a flow rate of 200 L/h, and the samples were obtained after the separation from the corresponding sub-system at the condition of steady state of water flow. A digital water quality measurement was operated to evaluate the effluent after the separation process. The results show that the separation of turbidity up to 98% was obtained at the end of the processing system. The successful flotation of the suspended solid due to the zeta potential turn to zero up on the addition of flocculants lead to effective fine bubbles flotation. Finally, clean water was achieved in the performance test of mobile mini WTTP utilized with fine bubbles.
Synthesis of boehmite from aluminum trihydrate through facile hydrothermal method
Authors: Chamida Ridha Nurul , Rois Mahardika F. , Widiyastuti W. , Setyawan Heru
Published: October 2022

Boehmite (g-AlOOH) has demonstrated to have superior performance as coating material for battery separator, especially lithium-ion battery, due to its excellent wetting ability and thermal stability. The products of Bayer process from bauxite are typically in the form of aluminum trihydrate (ATH). Observing the phase diagram of Al2O3-H2O, it was assumed that the ATH might be converted into boehmite by controlling the pressure and temperature under hydrothermal condition. Therefore, the purpose of this work is to investigate the effect of operating conditions on the conversion of ATH to boehmite in a hydrothermal reactor. The experiments were carried out in a 100-mL hydrothermal reactor with a liquid filling volume of 30% and 50%. The reaction time was varied from 2 to 8 h. The hydrothermally treated ATH particles were characterized by an X-ray diffraction (XRD) and a scanning electron microscopy (SEM). The XRD patterns exhibited that the ATH has not been converted yet into boehmite at a reaction time of 2 h for all conditions. When the reaction time was prolonged to 4 h, ATH was transformed into boehmite at filling volume of 30% and 50%. It appears that liquid filling volume influences the transformation of ATH into boehmite. As observed by the SEM images, the morphology of particles also changed by the change of the crystalline phase. The particles changed from nearly spherical-shaped to cube and the particle size was typically larger
Occurrences of reciprocal sign epistasis in single- and multi-peaked theoretical fitness landscapes
Authors: Riehl Manda , Phillips Reed , Pudwell Lara , Chenette Nate
Published: October 2022

Fitness landscapes help model the theory of adaption. We consider genetic fitness landscapes abstractly as acyclic orientations of Boolean lattices under the assumptions laid out by Crona et al. We focus on occurrences of reciprocal sign epistasis (RSE) on the faces of the lattice. We computationally study which combinations of numbers of peaks and RSE faces are possible, and we determine limits on occurrences of RSE faces in both single-peaked and multi-peaked landscapes. Our main theorem extends a theorem of Poelwijk to show that any landscape with k peaks contains at least k − 1 RSE faces.
Growth chemistry of cobalt nitride by plasma enhanced atomic layer deposition
Authors: O’Donnell S , Snelgrove M , Shiel K , Weiland C , Hughes G , Woicik J , O’Neill D , Jose F , McFeely C , O’Connor R
Published: October 2022

State-of-the-art atomic layer deposition (ALD) and photoemission characterisation are applied to grow and characterise cobalt nitride, a material that has applications in renewable energy and semiconductor technologies. The growth process is characterised using an in situ cycle-by-cycle methodology to identify the main factors which underpin optimal material growth. The role of co-reactant dosing and substrate temperature is analysed in detail to demonstrate the impact these parameters have on the overall composition of the film. The in situ approach, combined with high-energy synchrotron-based photoemission studies of the resulting films, enables understanding of the bulk chemical properties without need for physical removal of material by sputtering. The results provide an insight into optimising plasma assisted ALD processes for deposition of cobalt nitride, and strategies for minimizing carbon incorporation into the film from the precursor ligands.
The nuanced nature of mesic refugia in arid landscapes: a tale of two peas
Authors: Bradbury Donna , Binks Rachel M , van Leeuwen Stephen , Coates David J , McArthur Shelley L , Macdonald Bronwyn M , Hankinson Margaret , Byrne Margaret
Published: October 2022

Background and Aims

Understanding how genetic diversity is distributed and maintained within species is a central tenet of evolutionary and conservation biology, yet is understudied in arid regions of the globe. In temperate, glaciated environments, high genetic diversity in plant species is frequently found in refugial areas, which are often associated with southern non-glaciated landscapes. In arid, unglaciated environments, landscape features providing mesic conditions are likely to be refugia, although our understanding needs more refinement in these biomes. We test whether refugia and nuclear diversity hotspots occur in high-elevation, topographically complex areas for co-distributed shrubs (Petalostylis labicheoides and Indigofera monophylla; Fabaceae) in the ancient, arid Pilbara bioregion of north-western Australia.

Methods

We conducted extensive sampling of the Pilbara (>1400 individuals from 62 widespread populations) to detect patterns in nuclear diversity and structure based on 13–16 microsatellite loci. Evidence of historical refugia was investigated based on patterns of diversity in three non-coding chloroplast (cp) sequence regions for approx. 240 individuals per species. Haplotype relationships were defined with median-joining networks and maximum likelihood phylogenetic trees.

Key Results

We found cpDNA evidence for a high-elevation refugium in P. labicheoides but not for I. monophylla that instead exhibited extraordinary haplotype diversity and evidence for persistence across a widespread area. Nuclear diversity hotspots occurred in, but were not exclusive to, high-elevation locations and extended to adjacent, low-elevation riparian areas in both species.

Conclusions

Phylogeographic refugia in arid environments may occur in high-elevation areas for some species but not all, and may be influenced by species-specific traits: a mesic montane refugium in P. labicheoides could be related to its preference for growth in water-gaining areas, while a lack of such evidence in I. monophylla could be related to maintenance of cpDNA diversity in a large soil seed bank and dynamic evolutionary history. Mesic environments created by the intersection of topographically complex landscapes with riparian zones can be contemporary reservoirs of genetic diversity in arid landscapes.
Social buffering diminishes fear response but does not equal improved fear extinction
Authors: Gorkiewicz Tomasz , Danielewski Konrad , Andraka Karolina , Kondrakiewicz Kacper , Meyza Ksenia , Kaminski Jan , Knapska Ewelina
Published: October 2022

Social support during exposure-based psychotherapy is believed to diminish fear and improve therapy outcomes. However, some clinical trials challenge that notion. Underlying mechanisms remain unknown, hindering the understanding of benefits and pitfalls of such approach. To study social buffering during fear extinction, we developed a behavioral model in which partner’s presence decreases response to fear-associated stimuli. To identify the neuronal background of this phenomenon, we combined behavioral testing with c-Fos mapping, optogenetics, and chemogenetics. We found that the presence of a partner during fear extinction training causes robust inhibition of freezing; the effect, however, disappears in subjects tested individually on the following day. It is accompanied by lowered activation of the prelimbic (PL) and anterior cingulate (ACC) but not infralimbic (IL) cortex. Accordingly, blocking of IL activity left social buffering intact. Similarly, inhibition of the ventral hippocampus–PL pathway, suppressing fear response after prolonged extinction training, did not diminish the effect. In contrast, inhibition of the ACC–central amygdala pathway, modulating social behavior, blocked social buffering. By reporting that social modulation of fear inhibition is transient and insensitive to manipulation of the fear extinction-related circuits, we show that the mechanisms underlying social buffering during extinction are different from those of individual extinction.
Improved Survival After Liver Transplantation for Patients With Human Immunodeficiency Virus (HIV) and HIV/Hepatitis C Virus Coinfection in the Integrase Strand Transfer Inhibitor and Direct-Acting Antiviral Eras
Authors: Jacob Jake Sheraj , Shaikh Anjiya , Goli Karthik , Rich Nicole E , Benhammou Jihane N , Ahmed Aijaz , Kim Donghee , Rana Abbas , Goss John A , Naggie Susanna , Lee Tzu-Hao , Kanwal Fasiha , Cholankeril George
Published: October 2022

Background

People with human immunodeficiency virus (HIV) with and without hepatitis C virus (HCV) coinfection had poor outcomes after liver transplant (LT). Integrase strand transfer inhibitors (INSTIs) and direct-acting antivirals (DAAs) have changed the treatment landscape for HIV and HCV, respectively, but their impact on LT outcomes remains unclear.

Methods

This retrospective analysis of adults with HIV monoinfection (n = 246) and HIV/HCV coinfection (n = 286) who received LT compared mortality in patients with HIV who received LT before versus after approval of INSTIs and in patients with HIV/HCV coinfection who received LT before versus after approval of DAAs. In secondary analysis, we compared the outcomes in the different eras with those of propensity score–matched control cohorts of LT recipients without HIV or HCV infection.

Results

LT recipients with HIV monoinfection did not experience a significant improvement in survival between the pre-INSTI and INSTI recipients with HIV (adjusted hazard ratio [aHR], 0.70 [95% confidence interval {CI}, .36–1.34]). However, recipients with HIV/HCV coinfection in the DAA era had a 47% reduction (aHR, 0.53 [95% CI, .31–9.2] in 1-year mortality compared with coinfected recipients in the pre-DAA era. Compared to recipients without HIV or HCV, HIV-monoinfected recipients had higher mortality during the pre-INSTI era, but survival was comparable between groups during the INSTI era. HIV/HCV-coinfected recipients also experienced comparable survival during the DAA era compared to recipients without HCV or HIV.

Conclusions

Post-LT survival for people with HIV monoinfection and HIV/HCV coinfection has improved with the introduction of INSTI and DAA therapy, suggesting that LT has become safer in these populations.
Effect of preoperative extracorporeal membrane oxygenation therapy on postventricular assist device outcomes: an analysis of the STS Pedimacs database
Authors: Peer Syed M , Koehl Devin A , Cantor Ryan S , Kirklin James K , Sinha Pranava
Published: October 2022

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) support prior to ventricular assist device (VAD) therapy is frequently used for stabilizing INTERMACS 1 and 2 paediatric patients. Data regarding outcomes with this strategy is limited.

METHODS

Patient characteristics and outcomes post-VAD therapy with and without preop ECMO support were compared. Survival and risk factor analysis was performed for all patients and INTERMACS profile 1 subgroup.

RESULTS

Of 541 INTERMACS 1 and 2 patients enrolled in Paediatric Interagency Registry for Mechanical Circulatory Support registry, 391 received primary VAD implantation and ECMO prior to VAD therapy was utilized in 150 patients. Younger age (P < 0.0001) and shock (P < 0.0001) were more common in group 2, with lower survival at 1, 6 and 12 months compared to group 1 (P < 0.0001). Freedom from infection (P = 0.03) was higher in group 1. Freedom from stroke (P = 0.7) was similar. Paracorporeal continuous flow devices led to poor survival in both groups 1 and 2 (P = 0.4). Implantable continuous flow (P < 0.0001) and paracorporeal pulsatile devices (P = 0.007) had better survival in primary VAD group. INTERMACS profile 1, lower weight, hepatic dysfunction, renal failure, paracorporeal continuous and percutaneous devices were associated with higher mortality. Preop ECMO therapy was not associated with higher mortality (P = 0.12). Survival of INTERMACS profile 1 patient was similar at 1, 6 and 12 months in both groups (P = 0.1).

CONCLUSIONS

INTERMACS profile 1, lower weight, hepatic dysfunction, renal failure and use of paracorporeal continuous flow or percutaneous assist devices are associated with a higher postoperative mortality. Preop ECMO therapy however is not independently associated with higher postop mortality.
Multiple origins, one evolutionary trajectory: gradual evolution characterizes distinct lineages of allotetraploidBrachypodium
Authors: Scarlett Virginia T , Lovell John T , Shao Mingqin , Phillips Jeremy , Shu Shengqiang , Lusinska Joanna , Goodstein David M , Jenkins Jerry , Grimwood Jane , Barry Kerrie , Chalhoub Boulos , Schmutz Jeremy , Hasterok Robert , Catalán Pilar , Vogel John P
Published: October 2022

The “genomic shock” hypothesis posits that unusual challenges to genome integrity such as whole genome duplication may induce chaotic genome restructuring. Decades of research on polyploid genomes have revealed that this is often, but not always the case. While some polyploids show major chromosomal rearrangements and derepression of transposable elements in the immediate aftermath of whole genome duplication, others do not. Nonetheless, all polyploids show gradual diploidization over evolutionary time. To evaluate these hypotheses, we produced a chromosome-scale reference genome for the natural allotetraploid grass Brachypodium hybridum, accession “Bhyb26.” We compared 2 independently derived accessions of B. hybridum and their deeply diverged diploid progenitor species Brachypodium stacei and Brachypodium distachyon. The 2 B. hybridum lineages provide a natural timecourse in genome evolution because one formed 1.4 million years ago, and the other formed 140 thousand years ago. The genome of the older lineage reveals signs of gradual post-whole genome duplication genome evolution including minor gene loss and genome rearrangement that are missing from the younger lineage. In neither B. hybridum lineage do we find signs of homeologous recombination or pronounced transposable element activation, though we find evidence supporting steady post-whole genome duplication transposable element activity in the older lineage. Gene loss in the older lineage was slightly biased toward 1 subgenome, but genome dominance was not observed at the transcriptomic level. We propose that relaxed selection, rather than an abrupt genomic shock, drives evolutionary novelty in B. hybridum, and that the progenitor species’ similarity in transposable element load may account for the subtlety of the observed genome dominance.
Seafloor depth controls seismograph orientation uncertainty
Authors: Sawaki Yasunori , Yamashita Yusuke , Ohyanagi Shukei , Garcia Emmanuel Soliman M , Ito Aki , Sugioka Hiroko , Takahashi Tsutomu , Shinohara Masanao , Ito Yoshihiro
Published: October 2022

This study evaluates the seafloor ambient noise environment that varies with the water depth based on a correction analysis of the horizontal sensor orientation for ocean-bottom seismographs. As ocean-bottom seismographs are mainly deployed as ‘free-fall’ installations, we have no information on which direction a horizontal sensor faces at the seafloor. An accurate sensor orientation is crucial for data processing based on seismic wavefields. Among several seismological approaches that use passive sources to correct the horizontal sensor azimuth, the particle motion of teleseismic Rayleigh waves is widely used for broad-band ocean-bottom seismographs. We performed seafloor seismic observations in the Hyuga-nada region at the western end of the Nankai subduction zone and deployed broad-band and short-period seismographs. However, studies have yet to investigate whether orientation correction via the Rayleigh-wave polarization method is valid for short-period data. The results of the Rayleigh wave method from our campaign observation data showed that the estimation uncertainty of short-period sensor orientations increased with a decreasing water depth; we observed a transition depth for the uncertainty at 2200–2600 m. The measurement quality, or the cross-correlation coefficient between the radial and Hilbert-transformed vertical components, also decreased at depths shallower than 2000 m. Moreover, an analysis of the noise power spectral densities showed that ambient noise levels during long periods (>10 s) increased with decreasing depth. Infragravity waves controlled vertical long-period noise levels, while ocean currents dominated horizontal long-period noise; both of these reduced the Rayleigh-wave signals as a function of environmental noise. Infragravity waves also likely distorted the Rayleigh waveforms. Both mechanisms contributed to the sudden rise in orientation uncertainty and low measurement quality at shallow stations (i.e. <2000 m). We confirmed that the variation in orientation uncertainty with the water depth can be used as an index for the ambient noise environment of the seafloor.
Simulating seismic multifrequency wavefields with the Fourier feature physics-informed neural network
Authors: Song Chao , Wang Yanghua
Published: October 2022

To simulate seismic wavefields with a frequency-domain wave equation, conventional numerical methods must solve the equation sequentially to obtain the wavefields for different frequencies. The monofrequency equation has the form of a Helmholtz equation. When solving the Helmholtz equation for seismic wavefields with multiple frequencies, a physics-informed neural network (PINN) can be used. However, the PINN suffers from the problem of spectral bias when approximating high-frequency components. We propose to simulate seismic multifrequency wavefields using a PINN with an embedded Fourier feature. The input to the Fourier feature PINN for simulating multifrequency wavefields is 4-D, namely the horizontal and vertical spatial coordinates of the model, the horizontal position of the source, and the frequency, and the output is multifrequency wavefields at arbitrary source positions. While an effective Fourier feature initialization strategy can lead to optimal convergence in training this network, the Fourier feature PINN simulates multifrequency wavefields with reasonable efficiency and accuracy.
Everyday capabilities were a path to resilience during COVID-19: a case study of five countries
Authors: Neill Rachel , Neel Abigail H , Cardona Carolina , Bishai David , Gupta Shivam , Mohan Diwakar , Jain Nishant , Basu Sharmishtha , Closser Svea
Published: October 2022

COVID-19 demanded urgent responses by all countries, with wide variations in the scope and sustainability of those responses. Scholarship on resilience has increasingly emphasized relational considerations such as norms and power and how they influence health systems’ responses to evolving challenges. In this study, we explored what influenced countries’ national pandemic responses over time considering a country’s capacity to test for COVID-19. To identify countries for inclusion, we used daily reports of COVID-19 cases and testing from 184 countries between 21st January 2020 and 31st December 2020. Countries reporting test data consistently and for at least 105 days were included, yielding a sample of 52 countries. We then sampled five countries representing different geographies, income levels and governance structures (Belgium, Ethiopia, India, Israel and Peru) and conducted semi-structured key informant interviews with stakeholders working in, or deeply familiar with, national responses. Across these five countries, we found that existing health systems capacities and political leadership determined how responses unfolded, while emergency plans or pandemic preparedness documents were not fit-for-purpose. While all five countries were successful at reducing COVID-19 infections at a specific moment in the pandemic, political economy factors complicated the ability to sustain responses, with all countries experiencing larger waves of the virus in 2021 or 2022. Our findings emphasize the continued importance of foundational public health and health systems capacities, bolstered by clear leadership and multisectoral coordination functions. Even in settings with high-level political leadership and a strong multisectoral response, informants wished that they—and their country’s health system—were more prepared to address the pandemic and maintain an effective response over time. Our findings challenge emergency preparedness as the dominant frame in pandemic preparedness and call for a continued emphasis on health systems strengthening to respond to future health shocks and a pandemic moving to endemic status.
Young adults’ knowledge, perceptions and use of cannabidiol products: a mixed-methods study
Authors: Wysota Christina N , Le Daisy , Clausen Michelle Elise , Ciceron Annie Coriolan , Fuss Caroline , Bennett Breesa , Romm Katelyn F , Duan Zongshuan , Berg Carla J
Published: October 2022

Cannabidiol (CBD) product regulatory efforts must be informed by research regarding consumer perceptions. This mixed-methods study examined CBD product information sources, knowledge, perceptions, use and use intentions among young adults. This study analyzed (i) Fall 2020 survey data from 2464 US young adults (Mage = 24.67, 51.4% ever users, 32.0% past 6-month users) and (ii) Spring 2021 qualitative interviews among 40 survey participants (27.5% past-month users). Overall, 97.9% of survey participants reported having heard of CBD, 51.4% ever/lifetime use and 32.0% past 6-month use. Survey participants learned about CBD from friends/family (58.9%), products/ads at retailers (36.4%), online content/ads (34.8%), CBD stores (27.5%) and social media (26.7%). One-fourth believed that CBD products were required to be US Food and Drug Administration-approved (24.9%), tested for safety (28.8%) and proven effective to be marketed for pain, anxiety, sleep, etc. (27.2%). Survey and interview participants perceived CBD as safe, socially acceptable and effective for addressing pain, anxiety and sleep. Interview findings expanded on prominent sources of marketing and product exposure, including online and specialty retailers (e.g. vape shops), and on participants’ concerns regarding limited regulation and/or evidence regarding CBD’s effectiveness/risks. Given young adults’ misperceptions about CBD, surveillance of CBD knowledge, perceptions and use is critical as the CBD market expands.
Diploid chromosome-level reference genome and population genomic analyses provide insights into Gypenoside biosynthesis and demographic evolution of Gynostemma pentaphyllum (Cucurbitaceae)
Authors: Zhang Xiao , Zhao Yuhe , Kou Yixuan , Chen Xiaodan , Yang Jia , Zhang Hao , Zhao Zhe , Zhao Yuemei , Zhao Guifang , Li Zhonghu
Published: October 2022

Gynostemma pentaphyllum (Thunb.) Makino is a perennial creeping herbaceous plant in the family Cucurbitaceae, which has great medicinal value and commercial potential, but urgent conservation efforts are needed due to the gradual decreases and fragmented distribution of its wild populations. Here, we report the high-quality diploid chromosome-level genome of G. pentaphyllum obtained using a combination of next-generation sequencing short reads, Nanopore long reads, and Hi-C sequencing technologies. The genome is anchored to 11 pseudo-chromosomes with a total size of 608.95 Mb and 26 588 predicted genes. Comparative genomic analyses indicate that G. pentaphyllum is estimated to have diverged from Momordica charantia 60.7 million years ago, with no recent whole-genome duplication event. Genomic population analyses based on genotyping-by-sequencing and ecological niche analyses indicated low genetic diversity but a strong population structure within the species, which could classify 32 G. pentaphyllum populations into three geographical groups shaped jointly by geographic and climate factors. Furthermore, comparative transcriptome analyses showed that the genes encoding enzyme involved in gypenoside biosynthesis had higher expression levels in the leaves and tendrils. Overall, the findings obtained in this study provide an effective molecular basis for further studies of demographic genetics, ecological adaption, and systematic evolution in Cucurbitaceae species, as well as contributing to molecular breeding, and the biosynthesis and biotransformation of gypenoside.
Borrowing strength from clinical trials in analysing longitudinal data from a treated cohort: investigating the effectiveness of acetylcholinesterase inhibitors in the management of dementia
Authors: Knight Ruth , Stewart Robert , Khondoker Mizanur , Landau Sabine
Published: October 2022

Background

Health care professionals seek information about effectiveness of treatments in patients who would be offered them in routine clinical practice. Electronic medical records (EMRs) and randomized controlled trials (RCTs) can both provide data on treatment effects; however, each data source has limitations when considered in isolation.

Methods

A novel modelling methodology which incorporates RCT estimates in the analysis of EMR data via informative prior distributions is proposed. A Bayesian mixed modelling approach is used to model outcome trajectories among patients in the EMR dataset receiving the treatment of interest. This model incorporates an estimate of treatment effect based on a meta-analysis of RCTs as an informative prior distribution. This provides a combined estimate of treatment effect based on both data sources.

Results

The superior performance of the novel combined estimator is demonstrated via a simulation study. The new approach is applied to estimate the effectiveness at 12 months after treatment initiation of acetylcholinesterase inhibitors in the management of the cognitive symptoms of dementia in terms of Mini-Mental State Examination scores. This demonstrated that estimates based on either trials data only (1.10, SE = 0.316) or cohort data only (1.56, SE = 0.240) overestimated this compared with the estimate using data from both sources (0.86, SE = 0.327).

Conclusions

It is possible to combine data from EMRs and RCTs in order to provide better estimates of treatment effectiveness.
Validating a membership disclosure metric for synthetic health data
Authors: El Emam Khaled , Mosquera Lucy , Fang Xi
Published: October 2022

Background

One of the increasingly accepted methods to evaluate the privacy of synthetic data is by measuring the risk of membership disclosure. This is a measure of the F1 accuracy that an adversary would correctly ascertain that a target individual from the same population as the real data is in the dataset used to train the generative model, and is commonly estimated using a data partitioning methodology with a 0.5 partitioning parameter.

Objective

Validate the membership disclosure F1 score, evaluate and improve the parametrization of the partitioning method, and provide a benchmark for its interpretation.

Materials and methods

We performed a simulated membership disclosure attack on 4 population datasets: an Ontario COVID-19 dataset, a state hospital discharge dataset, a national health survey, and an international COVID-19 behavioral survey. Two generative methods were evaluated: sequential synthesis and a generative adversarial network. A theoretical analysis and a simulation were used to determine the correct partitioning parameter that would give the same F1 score as a ground truth simulated membership disclosure attack.

Results

The default 0.5 parameter can give quite inaccurate membership disclosure values. The proportion of records from the training dataset in the attack dataset must be equal to the sampling fraction of the real dataset from the population. The approach is demonstrated on 7 clinical trial datasets.

Conclusions

Our proposed parameterization, as well as interpretation and generative model training guidance provide a theoretically and empirically grounded basis for evaluating and managing membership disclosure risk for synthetic data.