bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of electron cyclotron resonance heating on ion-driven fishbone instability
Authors: Zhang Runzhe , Cai Huishan , Chen Wei , Li Ding
Published: August 2023

The effect of electron cyclotron resonance heating (ECRH) on fishbone instability is studied based on the generalized energy principle. Off-axis ECRH plays a stabilizing role in fishbone instability, while on-axis ECRH does not distinctly change the growth rate. The frequency of fishbone instability increases (decreases) for off-axis (on-axis) ECRH. The effect of ECRH is greatest when power is deposited near the rational surface. More concentrated power deposition has a better stabilizing effect. Furthermore, the non-resonance effect of trapped energetic electrons is the main factor behind the stabilization effect in the off-axis case, while it has a weak effect in the on-axis case. The frequency of fishbone instability is changed mainly by the Shafranov shift effect on trapped energetic ions since it can change the precessional drift frequency. The Shafranov shift effect can also affect the growth rate because the onset threshold of energetic ion beta is related to the frequency. The effects of magnetic Reynolds number and slowing-down critical energy are weak and can be neglected. This provides the possibility of using off-axis ECRH targeted to the rational surface to control fishbone instability.
High temperature spin-triplet topological superconductivity in K2Cr3As3
Authors: Zheng Guo-qing
Published: August 2023

Spin-triplet superconductors are novel materials capable of harboring Majorana bound states that can be used in topological quantum computing. However, such bulk materials are still rare. Here we review the results that established K2Cr3As3 as a spin-triplet superconductor with transition temperature Tc
as high as 6.5 K. We focus on the multiple-phases feature, and its exquisite distance to a ferromagnetic quantum critical point which is likely responsible for the high Tc
. We touch on the topological aspects of the superconducting state, and suggest that it is a new route to the technical implementation using a topological spin-triplet superconductor at the highest temperature ever.
The in- and out-of-plane magnetisation of highly underdoped YBa2Cu3O6+x single crystals
Authors: Kokanović I , Cooper J R
Published: August 2023

Previously we have shown how measurements of static magnetic susceptibility χc(T) of YBa2Cu3O6+x single crystals for magnetic fields applied along the c-axis, and χab(T) for fields in the ab-plane, can give useful information about their thermodynamic properties which are still being hotly debated. SQUID magnetometry above the superconducting (s/c) transition temperature Tc is used for larger crystals, while piezolever torque magnetometry gives χc(T)-χab(T) for tiny crystals. Here we present new data for more heavily under-doped crystals with hole concentrations per CuO2 plane, p =0.058 to 0.073. We again find that the T-dependent anisotropy well above Tc arises from the pseudogap and the g-factor anisotropy, while at lower T there are Gaussian s/c fluctuations with a strong cut-off. This is possibly a different region where neutron scattering studies give evidence for competition between incommensurate magnetic short-range order and superconductivity. We have studied crystals with three values of x, measuring χc(T) and χab(T) immediately after fixing x by quenching on to a copper block and again after allowing sufficient time at room temperature for the Cu-O chains to order. Thus, we report data for three pairs of underdoped (UD) crystals with Tc ranging from 13 to 36 K, namely UD13 and UD20, UD15 and UD30, UD23 and UD36. As found previously for polycrystalline samples, ordering the Cu-O chains increases Tc and substantially reduces the Curie term. These are isotropic, in contrast to the Pauli-like susceptibility from the CuO2 planes where there is g factor anisotropy, and this allows us to make a powerful novel analysis. At higher T, χc(T)- χab(T) varies as a + bT where the bT term arises from the pseudogap. At lower T, deviations from this behaviour are analysed in terms of 2D or 3D Gaussian s/c fluctuations to obtain in-plane coherence lengths and upper critical fields as T→0.
Peak Effect Induced by Heavy-ion Irradiation in 2H-NbSe2 Single Crystals
Authors: Li Wenjie , Pyon Sunseng , Okayasu Satoru , Tamegai Tsuyoshi
Published: August 2023

Peak effect has been studied in 2H-NbSe2 single crystals with splayed columnar defects introduced by 320 MeV Au irradiation. Through the magnetic relaxation experiments, correspondence between the peak effect and magnetic relaxation has been observed. However, by calculating the critical current density (J
c) much before the first measurement using a SQUID magnetometer based on the relaxation rate S, it is found that the peak effect is present even at the very early stage of relaxation, indicating that it is caused by the magnetic field dependence of pinning force.
Stable operation characteristics and perspectives of the large-current HTS STARS conductor
Authors: Yanagi N , Narushima Y , Onodera Y , Garfias-Dávalos D , Ito S , Terazaki Y , Hamaguchi S , Chikaraishi H , Takada S , Hirano N , Takahata K
Published: August 2023

The High-Temperature Superconducting (HTS) magnet option has been explored for fusion reactors as well as for next-generation fusion experimental devices. The Stacked Tapes Assembled in Rigid Structure (STARS) conductor uses HTS tapes with simple stacking without twisting and transposition. A practically applicable STARS conductor is presently being developed with an operating current of 18 kA at 20 K temperature and ~15 T magnetic field. The conductor is required to have a high current density of 80 A/mm2. For the second stage of the conductor development, internal electrical insulation is applied between the copper stabilizer casing and the outer stainless-steel jacket, and a 6-m conductor sample was fabricated in a solenoid coil shape with a 600-mm diameter and three turns. The coiled sample was tested in 8 T, 20 K using a facility equipped with a maximum 13-T, 700-mm bore solenoid coil. Excitation up to the rated current of 18 kA was successfully attained with stable operation. The characteristics of the conductor observed during the excitation test are discussed.
Performance evaluation of superconductive-assisted machining (SUAM) with superconducting tape and two permanent magnets
Authors: Iwasaki S , Ishii H , Kinoshita Y , Otabe E S , Matsuo K , Nakasaki T , Suzuki K
Published: August 2023

In this study, the repulsive force causing magnetic levitation for superconductive-assisted machining (SUAM) is calculated using the finite element method. Although bulk superconductors have been used for SUAM, here, we propose a magnetic levitation tool that uses superconducting tape. To obtain a stronger repulsive force, various models of a SUAM are designed and calculated. The results show that a strong repulsive force can be obtained by using two permanent magnets. In addition, even if the superconducting tape is rotated during stacking due to stacking errors, the repulsive force is not affected, indicating that there is no need to optimize the stacking method. Therefore, we expect that increasing the number of layers will generate a repulsive force that is greater than that obtained with bulk superconductors.
Orientation degrees in Dy123 powders by using Linear-drive type Modulated Rotating Magnetic Field system
Authors: Ali W B , Adachi S , Kimura F , Horii S
Published: August 2023

Bi-axial magnetic alignment of DyBa2Cu3Oy (y ~ 7) grains with high in-plane orientation degrees has been achieved using only permanent magnets as magnetic field sources. When compared to electromagnets such as a superconducting magnet, arrayed magnets offer a lower cost and greater versatility as magnetic field sources for magnetic alignment. In this study, permanent magnets were arranged in such a way that they were able to create a rotating magnetic field with a strength of 0.8 T-class. This helps with the magnetic alignment of functional materials like cuprate superconductors.
Trapping Magnetic Field in Bulk Iron-based Superconductor Sintered under High Pressure
Authors: Wu Wenxi , Pyon Sunseng , Tamegai Tsuyoshi
Published: August 2023

We fabricated two bulk superconductors of (Ba,Na)Fe2As2 using a cubic press and hot press sintering technique. For bulk #1 sintered by cubic press, despite its small dimensions, with diameter 4.1 mm and height 3.64 mm, a trapped field value of ~9.97 kG has been achieved on its surface, which is only 230 G lower than the value reported in a bulk with a diameter of 10 mm before. Critical current density (J
c) is estimated to be 81.2 kA cm−2 at 4.2 K under self-field, which is larger than the value reported before. It suggests that the improvement of J
c achieved by high pressure could make up for the negative influence from the smaller dimensions and achieve a large trapped field. In the second larger bulk #2 sintered by hot pressing technique, with diameter 9.45 mm and height 4.58 mm, the value of J
c is ~ 33.9 kA cm−2 and the trapped field is ~8.81 kG on the surface. The expected better texturing has not been observed. Possible origins for inferior properties of bulk #2 are discussed.
Demonstration and thermal equilibrium analysis of a 10 kJ capacity energy storage coil made of MgB2 with liquid hydrogen indirect cooling
Authors: Inomata R , Onji T , Yagai T , Makida Y , Shintomi T , Komagome T , Hirano N , Hamajima T
Published: August 2023

We have demonstrated an advanced superconducting power conditioning system, in which a superconducting magnetic energy storage (SMES) device, a generator based on a fuel cell (FC), and an electrolyzer are used to compensate for electricity fluctuations over a wide frequency range, combined with a liquid hydrogen storage system to both cool the SMES and provide pure hydrogen gas to the FC and other gas-dependent systems. To manufacture the coils for the SMES, we used MgB2, whose critical temperature is below the boiling temperature of hydrogen. We developed a 10 kJ SMES coil system indirectly cooled by liquid hydrogen using thermosyphon passive heat exchange to isolate the flammable hydrogen from the electrical components. We performed a successful demonstration of this system for both DC and AC currents ramped at different rates. In the present study, we use computer simulations involving heat balance equations to evaluate the stability of the system. The results obtained are expected to lead to the design of future large-capacity energy storage systems, such as the MJ class, which offer comparable performance to conventional NbTi SMES devices.
Electromagnetic analysis of fully superconducting motors employing dilute gas rotor and liquid hydrogen stator cooling structure
Authors: Terao Yutaka , Akasaka Kazuki , Ohsaki Hiroyuki , Okai Keiichi , Taguchi Hideyuki
Published: August 2023

This paper deals with fully superconducting motors (FSCMs) applied in the electric aircraft propulsion systems; the stator employs the MgB2-superconductor (SC) armature windings cooled at 20 K by using liquid hydrogen, while the rotor has the field windings made of REBCO SC wires cooled below 50 K via heat conduction and convective heat transfer by using dilute gas. The cooling structure of rotor can be simplified by adopting this type of design. The authors evaluated the optimal design for FSCM by using analytical equations and loss analysis via FEM. The FSCM characteristics were compared between ones using electromagnetic shield made of stainless steel (SUS) and ones using the shield made of copper (Cu); the results show that the output density using the SUS shield achieved 18.3 kW/kg, and that in terms of the loss estimation via FEM, both the motors had the efficiency over 98.5%.
Removal of SUS304 fine particles transformed into martensite by the high gradient magnetic separation under dry condition
Authors: Chen H , Yang Y , Miura O
Published: August 2023

The interfusion of impurities such as metallic wear debris has been a major issue in the manufacturing process of foods, medicines and industrial products. Such debris originates with wearing of stainless-steel pipe joints or mechanical moving parts. Since the debris shows ferromagnetic properties by undergoing the strain-induced martensitic transformation of non-magnetic SUS304 (X5CrNi18-10), the magnetic separation system is much efficient to remove such debris from raw materials. In order to study the magnetic separation properties for the martensitic transformation fine particles, the several kinds of magnetic powder with different magnetization were prepared by controlling the amount of martensitic transformation by heat-treating SUS304 powders. The magnetic separation performance was evaluated by the high gradient magnetic separation (HGMS) experiments using the multilayer unidirectional magnetic wire filter under dry condition. The experimental results and FEM particle trajectory simulations revealed that the SUS304 powders transformed into martensite were removed at high speed of 0.1 m/s by the superconducting HGMS in a relatively low magnetic field.
Birational maps from polarization and the preservation of measure and integrals
Authors: McLachlan Robert I , McLaren David I , Quispel G R W
Published: August 2023

The main result of this paper is the discretization of second-order Hamiltonian systems of the form

x
¨

=
−
K
∇
W
(
x
)

, where K is a constant symmetric matrix and

W
:

R

n

→

R

is a polynomial of degree

d
⩽
4

in any number of variables n. The discretization uses the method of polarization and preserves both the energy and the invariant measure of the differential equation, as well as the dimension of the phase space. This generalizes earlier work for discretizations of first order systems with d = 3, and of second order systems with d = 4 and n = 1.
Explicit expressions for stationary states of the Lindblad equation for a finite state space
Authors: Fernengel Bernd Michael , Drossel Barbara
Published: August 2023

The Lindblad equation describes the time evolution of a density matrix of a quantum mechanical system. Stationary solutions are obtained by time-averaging the solution, which will in general depend on the initial state. We provide an analytical expression for the steady states of the Lindblad equation using the quantum jump unraveling, a version of an ergodic theorem, and the stationary probabilities of the corresponding discrete-time Markov chains. Our result is valid when the number of states appearing the in quantum trajectory is finite. The classical case of a Markov jump-process is recovered as a special case, and differences between the two are discussed.
Targeted micro-heterogeneity in bioinks allows for 3D printing of complex constructs with improved resolution and cell viability
Authors: Maciel Bruna R , Grimm Alisa , Oelschlaeger Claude , Schepers Ute , Willenbacher Norbert
Published: August 2023

Three-dimensional bioprinting is an evolving versatile technique for biomedical applications. Ideal bioinks have complex micro-environment that mimic human tissue, allow for good printing quality and provide high cell viability after printing. Here we present two strategies for enhancing gelatin-based bioinks heterogeneity on a 1–100 µm length scale resulting in superior printing quality and high cell viability. A thorough spatial and micro-mechanical characterization of swollen hydrogel heterogeneity was done using multiple particle tracking microrheology. When poly(vinyl alcohol) is added to homogeneous gelatin gels, viscous inclusions are formed due to micro-phase separation. This phenomenon leads to pronounced slip and superior printing quality of complex 3D constructs as well as high human hepatocellular carcinoma (HepG2) and normal human dermal fibroblast (NHDF) cell viability due to reduced shear damage during extrusion. Similar printability and cell viability results are obtained with gelatin/nanoclay composites. The formation of polymer/nanoclay clusters reduces the critical stress of gel fracture, which facilitates extrusion, thus enhancing printing quality and cell viability. Targeted introduction of micro-heterogeneities in bioinks through micro-phase separation is an effective technique for high resolution 3D printing of complex constructs with high cell viability. The size of the heterogeneities, however, has to be substantially smaller than the desired feature size in order to achieve good printing quality.
Studying the structural and optical properties of Er3+ doped TiO2 powders synthesized by the sol-gel process
Authors: Le T T Giang , Tran Kim Chi , Cao T M Dung , Nguyen T P Thanh , Van Tran T T
Published: August 2023

A series of TiO2:xEr powders (with x from 0% to 1% at.) was synthesised by a simple sol–gel process. The structural and optical properties were studied in detail using diffusion reflection spectroscopy, x-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy, and energy-dispersive x-ray spectroscopy, to systematically determine the band edge, morphology, and structural properties of both undoped and Er-doped TiO2 samples. Notably, the introduction of Er dopants in the TiO2 matrix results in a decrease in both the band gap and crystallite size as well as the anatase phase of host matrix TiO2 remained in the anatase phase even at 800 °C. The heat treatment temperature has an insignificant effect on the green/red emission ratio of Er ions. However, this ratio strongly depends on excitation wavelengths corresponding to down-conversion and up-conversion processes. The colour emission of TiO2:Er is easily tunable from green to yellow under different excitations. The emission mechanism of TiO2:Er is proposed based on spectroscopy techniques. These findings reveal that the TiO2:Er powders are potential materials for labelling and photocatalyst applications.
Charge transport properties of interstitially doped graphene: a first-principles study
Authors: Rositawati Dwi Nugraheni , Absor Moh. Adhib Ulil , Triyana Kuwat , Santoso Iman
Published: August 2023

The role of interstitial atomic doping on transport properties of graphene was systematically studied using first-principles density functional theory (DFT). The study revealed that interstitial Au doping results in a p-type transfer of holes to graphene as the dopant concentration increases to 25%, with the Dirac point shifting to the Fermi level and localised states of atomic dopants appearing at the Fermi level and at energy of −1 eV. Ca, Ag and Al interstitial doping induces an n-type transfer of electrons to graphene with the Dirac point moving away from the Fermi level and localised states appearing at the Fermi level and at energy levels of ∼2 eV for Ca, around −3.5 eV for Ag, −3.5 eV and ∼1.6 eV for Al. As the dopant concentration increases further to 50%, the number of holes (or electrons) decreases for all dopants, except for Ca, as the localised state at the Fermi level disappears, and the Dirac point returns towards the Fermi level. Our research provides insights into how to reconcile the localised state and the number of charge carriers that play a significant role in the transport properties of interstitial doped graphene.
Mechanical properties and fracture behavior of Al(111)/MgAlB4(0001) interface in Al matrix composites: a first-principle calculation study
Authors: Wang Mingjie , Zhang Yijie , Zheng Hongxing , Ru Zhongyun , Yang Xiaoyu
Published: August 2023

Hexagonal crystal MgAlB4 is a strengthening phase in Al matrix composites, which can significantly improve ultimate tensile strength. In this paper, the surface perform, interfacial bonding characteristic, fracture mechanism, and electronic properties of the Al(111)/MgAlB4(0001) interface were thoroughly investigated by the first principles method. The results reveal that the top-site and bridge-site configurations were more unstable than the hollow-site. Besides, from the calculated results of interfacial energy and work of adhesion, the hollow-stacked Al(111)/B(Al)-terminated/MgAlB4(0001) interface expresses stronger stability than other interfacial models, which is attributable to the higher work of adhesion and lower interfacial energy of the hollow-stacked Al(111)/B(Al)-terminated/MgAlB4(0001) interface. Analysis of electronic structure reveals that the Al-termination and Mg-termination Al(111)/MgAlB4(0001) interface presents Al-Al and Al-Mg metallic bonds at the interface, respectively, but the B(Al)-termination Al(111)/MgAlB4(0001) interface expresses strong Al-B covalent bonds characteristic, which leads to the highest interface stability. The results of tensile fracture revealed that the HCP stacked B(Al)-termination interface transferred the external stress to Al bulk, due to the Al-B covalent bond formed near the interface. Therefore, ceramic phase MgAlB4 can effectively promote the particle reinforcement of Al matrix composites.
Possible linkage of sea surface height anomaly, surface wind stress and sea surface temperature with the falling ice radiative effects under a gradual warming scenario
Authors: Tsai Yu-Cian , Li Jui-Lin F , Xu Kuan-Man , Lee Wei-Liang , Jiang Jonathan H , Fetzer Eric J , Yu Jia-Yuh
Published: August 2023

This study investigates the possible linkage of sea surface height anomaly (SSHA), sea surface temperature (SST) and surface wind stress (TAU) with the falling ice radiative effects (FIREs) over the Pacific Ocean under the CMIP5 scenario of 1% CO2 increase per year (1pctCO2) for 140 years. Two sensitivity experiments using the fully-coupled ocean-atmosphere CESM1-CAM5 model are compared: one with FIREs (SON) and the other without (NOS). The warming period of the last 20 year is compared to the control period of the first 20 years. The mean state of the first 20 years exhibits a stronger west-east SSHA gradient in SON than in NOS over the Pacific Ocean, attributed to the stronger prevailing easterly trade winds and the SST pattern of being warmer in the western Pacific but colder in the eastern Pacific. In the last 20 years, SON continues to display a stronger SSHA west-east gradient with higher sea level and SST over the western Pacific Ocean compared to NOS. In the southwest Pacific, stronger trade winds are linked with the wind-evaporation-SST feedback, leading to a more significant decline in SSHA there in SON than in NOS. The CMIP5 ensemble mean shows similar relationships of SSHA with TAU and SST to those of NOS when both are compared against SON, highlighting the importance of FIREs in the SSH projection over the Pacific Ocean and the impact of FIREs on the changing relationships between SSHA, SST and TAU under global warming.
Strengths-based Approaches—Perspectives from Practitioners
Authors: Caiels James , Silarova Barbora , Milne Alisoun J , Beadle-Brown Julie
Published: August 2023

Despite its popularity, relatively little is known about strengths-based approaches in adult social work. In order to explore how strengths-based models and approaches are developed and implemented in social work and social care in England, and how these models are impacting practice, a two-stage project was conducted between December 2020 and October 2021. An online survey was completed by thirty-two respondents and a sub-sample of ten semi-structured interviews were conducted with social work and social care professionals involved in organising, managing, delivering or commissioning strengths-based approaches. The majority of participants were social workers. A range of positive outcomes were reported including improved reported well-being and satisfaction for people accessing services and enriched interactions (greater empathy, trust, better rapport), particularly for social workers. Challenges included incompatibility of systems and organisational structures; workload pressures and a depleted workforce; limited resources and applying the model at crisis point. The principles and values associated with adopting a strengths-based approach appear consistent with providing high-quality social work. The challenge for researchers—and to some extent practitioners—is how to meaningfully capture the nuanced impact of such a multi-dimensional approach. The challenge for policy is how to operationalise and replicate the benefits.
Exploring the merits of geographical diversification of solar PV power plants for a resilient PV-dominated electricity grid in India
Authors: Ghosh Saikat , Roy Jatindra Nath , Chakraborty Chandan
Published: August 2023

India is highly dependent on solar photovoltaics (PV) to harness its vast solar resource potential and combat climate change. However, $\sim$90% of the installed PV capacity in India is concentrated in the top nine states, with the remaining states lagging behind. The research reveals that during monsoons, heavy cloud cover and rain lead to high solar resource variability, intermittency and the risk of very low PV generation, which can result in reliability issues in future PV-dominated electricity grids. Although energy storage can help in overcoming high intermittency, there are multiple challenges associated with it. The novelty of this study lies in demonstrating the benefits of combining multiple PV sites in various regions to mitigate the risks of low PV generation and high variability. The variability of individual sites was found to be up to $\sim$3.5 times higher than the variability of combined generation. During noon, prominent solar park sites like Bhadla and NP Kunta experience a decrease in power generation to values as low as $\sim$10% of the rated PV capacity. However, the minimum generation of the large-scale dispersed PV generation is $>$30%. Furthermore, the research identifies other benefits of dispersing PV generation across the country, viz., reduction of seasonal variability by adding PV capacity in the southern region, widening of the PV generation span, more room for PV capacity addition, reduction in storage and ramping needs, utilization of hydroelectric potential of the north-east and PV potential of Ladakh, and creating opportunities for sustainable development in rural agrarian regions through agrivoltaics.
Genetic testing in focal segmental glomerulosclerosis: in whom and when?
Authors: Tato Ana María , Carrera Noa , García-Murias Maria , Shabaka Amir , Ávila Ana , Mora Mora María Teresa , Rabasco Cristina , Soto Karina , de la Prada Alvarez Francisco Jose , Fernández-Lorente Loreto , Rodríguez-Moreno Antolina , Huerta Ana , Mon Carmen , García-Carro Clara , González Cabrera Fayna , Navarro Juan Antonio Martín , Romera Ana , Gutiérrez Eduardo , Villacorta Javier , de Lorenzo Alberto , Avilés Beatriz , Garca-González Miguel Angel , Fernández-Juárez Gema
Published: August 2023

Background

Genetic causes are increasingly recognized in patients with focal segmental glomerulosclerosis (FSGS), but it remains unclear which patients should undergo genetic study. Our objective was to determine the frequency and distribution of genetic variants in steroid-resistant nephrotic syndrome FSGS (SRNS-FSGS) and in FSGS of undetermined cause (FSGS-UC).

Methods

We performed targeted exome sequencing of 84 genes associated with glomerulopathy in patients with adult-onset SRNS-FSGS or FSGS-UC after ruling out secondary causes.

Results

Seventy-six patients met the study criteria; 24 presented with SRNS-FSGS and 52 with FSGS-UC. We detected FSGS-related disease-causing variants in 27/76 patients (35.5%). There were no differences between genetic and non-genetic causes in age, proteinuria, glomerular filtration rate, serum albumin, body mass index, hypertension, diabetes or family history. Hematuria was more prevalent among patients with genetic causes. We found 19 pathogenic variants in COL4A3–5 genes in 16 (29.3%) patients. NPHS2 mutations were identified in 6 (16.2%) patients. The remaining cases had variants affecting INF2, OCRL, ACTN4 genes or APOL1 high-risk alleles. FSGS-related genetic variants were more common in SRNS-FSGS than in FSGS-UC (41.7% vs 32.7%). Four SRNS-FSGS patients presented with NPHS2 disease-causing variants. COL4A variants were the most prevalent finding in FSGS-UC patients, with 12 patients carrying disease-causing variants in these genes.

Conclusions

FSGS-related variants were detected in a substantial number of patients with SRNS-FSGS or FSGS-UC, regardless of age of onset of disease or the patient's family history. In our experience, genetic testing should be performed in routine clinical practice for the diagnosis of this group of patients.
Whole Blood DNA Methylation Changes Are Associated with Anti-TNF Drug Concentration in Patients with Crohn’s Disease
Authors: Lin Simeng , Hannon Eilis , Reppell Mark , Waring Jeffrey F , Smaoui Nizar , Pivorunas Valerie , Guay Heath , Chanchlani Neil , Bewshea Claire , Bai Benjamin Y H , Kennedy Nicholas A , Goodhand James R , Mill Jonathan , Ahmad Tariq
Published: August 2023

Background and Aims

Anti-tumour necrosis factor [TNF] treatment failure in patients with inflammatory bowel disease [IBD] is common and frequently related to low drug concentrations. In order to identify patients who may benefit from dose optimisation at the outset of anti-TNF therapy, we sought to define epigenetic biomarkers in whole blood at baseline associated with anti-TNF drug concentrations at week 14.

Methods

DNA methylation from 1104 whole blood samples from 385 patients in the Personalised Anti-TNF Therapy in Crohn’s disease [PANTS] study were assessed using the Illumina EPIC Beadchip [v1.0] at baseline and weeks 14, 30, and 54. We compared DNA methylation profiles in anti-TNF-treated patients who experienced primary non-response at week 14 if they were assessed at subsequent time points and were not in remission at week 30 or 54 [infliximab n = 99, adalimumab n = 94], with patients who responded at week 14 and when assessed at subsequent time points were in remission at week 30 or 54 [infliximab n = 99, adalimumab n = 93].

Results

Overall, between baseline and week 14, we observed 4999 differentially methylated positions [DMPs] annotated to 2376 genes following anti-TNF treatment. Pathway analysis identified 108 significant gene ontology terms enriched in biological processes related to immune system processes and responses. Epigenome-wide association [EWAS] analysis identified 323 DMPs annotated to 210 genes at baseline associated with higher anti-TNF drug concentrations at Week 14. Of these, 125 DMPs demonstrated shared associations with other common traits [proportion of shared CpGs compared with DMPs] including body mass index [23.2%], followed by C-reactive protein [CRP] [11.5%], smoking [7.4%], alcohol consumption per day [7.1%], and IBD type [6.8%]. EWAS of primary non-response to anti-TNF identified 20 DMPs that were associated with both anti-TNF drug concentration and primary non-response to anti-TNF with a strong correlation of the coefficients [Spearman’s rho = -0.94, p <0.001].

Conclusion

Baseline DNA methylation profiles may be used as a predictor for anti-TNF drug concentration at week 14 to identify patients who may benefit from dose optimisation at the outset of anti-TNF therapy.
Sex differences in symptoms of anxiety, depression, post-traumatic stress disorder, and cognitive function among survivors of out-of-hospital cardiac arrest
Authors: Grand Johannes , Fuglsbjerg Cecilie , Borregaard Britt , Wagner Mette Kirstine , Kragh Astrid Rolin , Bekker-Jensen Ditte , Mikkelsen Astrid Duus , Møller Jacob Eifer , Glud Heidi , Hassager Christian , Kikkenborg Selina , Kjaergaard Jesper
Published: August 2023

Aims

Anxiety, depression, and post-traumatic stress disorder (PTSD) among out-of-hospital cardiac arrest (OHCA) survivors may impact long-term recovery. Coping and perception of symptoms may vary between sexes. The aim was to explore sex differences in psychological consequences following OHCA.

Methods and results

This was a prospective observational study of OHCA survivors who attended a structured 3-month follow-up. Symptoms of anxiety/depression were measured using the Hospital Anxiety and Depression Scale, range 0–21, with a cut-off score of ≥8 for significant symptoms; PTSD was measured with the PTSD Checklist for DSM-5 (PCL-5), range 0–80. A score of ≥33 indicated PTSD symptoms. Cognitive function was assessed by the Montreal Cognitive Assessment. From 2016 to 2021, 381 consecutive comatose OHCA survivors were invited. Of these, 288 patients (76%) participated in the follow-up visit [53 (18%) females out of 80 survivors and 235 (82%) males out of 300 alive at follow-up (78%)]. Significant symptoms of anxiety were present in 47 (20%) males and 19 (36%) females (P = 0.01). Significant symptoms of PTSD were present in 30% of males and 55% of females (P = 0.01). Adjusting for pre-specified covariates using multivariable logistic regression, female sex was significantly associated with anxiety [odds ratio (OR): 2.18, confidence interval (CI): 1.09–4.38, P = 0.03]. This difference was especially pronounced among young females (below median age, ORadjusted: 3.31, CI: 1.32–8.29, P = 0.01) compared with young males. No significant sex difference was observed for depression or cognitive function.

Conclusion

Symptoms of anxiety and PTSD are frequent in OHCA survivors, and female survivors report significantly more symptoms of anxiety and PTSD compared with males. In particular, young females were significantly more symptomatic than young males.
Genetic Ablation of Prorenin Receptor in the Rostral Ventrolateral Medulla Influences Blood Pressure and Hydromineral Balance in Deoxycorticosterone-Salt Hypertension
Authors: Mathieu Natalia M , Fekete Eva M , Muskus Patricia C , Brozoski Daniel T , Lu Ko-Ting , Wackman Kelsey K , Gomez Javier , Fang Shi , Reho John J , Grobe Connie C , Vazirabad Ibrahim , Mouradian Gary C , Hodges Matthew R , Segar Jeffrey L , Grobe Justin L , Sigmund Curt D , Nakagawa Pablo
Published: August 2023

Non-enzymatic activation of renin via its interaction with prorenin receptor (PRR) has been proposed as a key mechanism of local renin–angiotensin system (RAS) activation. The presence of renin and angiotensinogen has been reported in the rostral ventrolateral medulla (RVLM). Overactivation of bulbospinal neurons in the RVLM is linked to hypertension (HTN). Previous studies have shown that the brain RAS plays a role in the pathogenesis of the deoxycorticosterone (DOCA)-salt HTN model. Thus, we hypothesized that PRR in the RVLM is involved in the local activation of the RAS, facilitating the development of DOCA-salt HTN. Selective PRR ablation targeting the RVLM (PRRRVLM-Null mice) resulted in an unexpected sex-dependent and biphasic phenotype in DOCA-salt HTN. That is, PRRRVLM-Null females (but not males) exhibited a significant delay in achieving maximal pressor responses during the initial stage of DOCA-salt HTN. Female PRRRVLM-Null subsequently showed exacerbated DOCA-salt-induced pressor responses during the “maintenance” phase with a maximal peak at 13 d on DOCA-salt. This exacerbated response was associated with an increased sympathetic drive to the resistance arterioles and the kidney, exacerbated fluid and sodium intake and output in response to DOCA-salt, and induced mobilization of fluids from the intracellular to extracellular space concomitant with elevated vasopressin. Ablation of PRR suppressed genes involved in RAS activation and catecholamine synthesis in the RVLM but also induced expression of genes involved in inflammatory responses. This study illustrates complex and sex-dependent roles of PRR in the neural control of BP and hydromineral balance through autonomic and neuroendocrine systems.

Graphical abstract
Genome Report: chromosome-scale genome assembly of the African spiny mouse (Acomys cahirinus)
Authors: Nguyen Elizabeth Dong , Fard Vahid Nikoonejad , Kim Bernard Y , Collins Sarah , Galey Miranda , Nelson Branden R , Wakenight Paul , Gable Simone M , McKenna Aaron , Bammler Theo K , MacDonald Jim , Okamura Daryl M , Shendure Jay , Beier David R , Ramirez Jan Marino , Majesky Mark W , Millen Kathleen J , Tollis Marc , Miller Danny E
Published: August 2023

There is increasing interest in the African spiny mouse (Acomys cahirinus) as a model organism because of its ability for regeneration of tissue after injury in skin, muscle, and internal organs such as the kidneys. A high-quality reference genome is needed to better understand these regenerative properties at the molecular level. Here, we present an improved reference genome for A. cahirinus generated from long Nanopore sequencing reads. We confirm the quality of our annotations using RNA sequencing data from 4 different tissues. Our genome is of higher contiguity and quality than previously reported genomes from this species and will facilitate ongoing efforts to better understand the regenerative properties of this organism.
Phenotypic defects from the expression of wild-type and pathogenic TATA-binding proteins in new Drosophila models of Spinocerebellar Ataxia Type 17
Authors: Patel Nikhil , Alam Nadir , Libohova Kozeta , Dulay Ryan , Todi Sokol V , Sujkowski Alyson
Published: August 2023

Spinocerebellar Ataxia Type 17 (SCA17) is the most recently identified member of the polyglutamine (polyQ) family of disorders, resulting from abnormal CAG/CAA expansion in the TATA box-binding protein (TBP), an initiation factor essential for of all eukaryotic transcription. A largely autosomal dominant inherited disease, SCA17, is unique in both its heterogeneous clinical presentation and low incidence of genetic anticipation, the phenomenon in which subsequent generations inherit longer polyQ expansions that yield earlier and more severe symptom onset. Like other polyQ disease family members, SCA17 patients experience progressive ataxia and dementia, and treatments are limited to preventing symptoms and increasing quality of life. Here, we report 2 new Drosophila models that express human TBP with polyQ repeats in either wild-type or SCA17 patient range. We find that TBP expression has age- and tissue-specific effects on neurodegeneration, with polyQ-expanded SCA17 protein expression generally having more severe effects. In addition, SCA17 model flies accumulate more aggregation-prone TBP, with a greater proportion localizing to the nucleus. These new lines provide a new resource for the biochemical characterization of SCA17 pathology and the future identification of therapeutic targets.
Motivations to use multifunctional public goods in organizations: using agent-based modeling to explore differential uses of enterprise social media
Authors: Foote Jeremy , Treem Jeffrey W , van den Hooff Bart , Honcoop Marjolijn
Published: August 2023

This work conceptualizes enterprise social media (ESM) as a multifunctional public good that both supports communication that connects users directly and allows users to contribute or access communal information. We show how differing motivations to use an ESM—connective or communal goals—interact with individuals’ perceptions of activity on a platform, and the consequences this has for individual participation decisions and the viability of the digital space. We begin with a case study of the adoption of an ESM platform within a single organization. We then apply findings from this case study, combined with broader theories of technology adoption, to create agent-based simulations. We show that the connective and communal aspects of an ESM complement each other and can spur adoption; we also identify the importance of information decay as a variable influencing collective adoption. We end with a discussion of the theoretical and practical implications of our results.
Novel SCCmec variants in clonal complex 398 and lineage-specific pseudo-SCCmec identified in ST88 MRSA from invasive bloodstream infections in China
Authors: Zhou Wangxiao , Jin Ye , Shen Ping , Chen Weiwei , Chen Yunbo , Xiao Yonghong
Published: August 2023

Background

Methicillin resistance in Staphylococcus aureus is primarily due to the mecA gene found in highly diverse staphylococcal cassette chromosome mec (SCCmec) elements, with an increasing number of variants being continually discovered.

Objectives

To characterize two novel SCCmec variants identified in clonal complex (CC) 398 strains and lineage-specific pseudo-SCCmec elements in the ST88 clone.

Methods

WGS and comparative genomic analysis were used to elucidate the SCCmec element diversity of representative isolates.

Results

The non-typeable 47 kb SCCmec found in the CC398 strain SKLX55795 represents a novel subtype of XIV, showing significant differences in structural organization and genetic content within the joining regions compared with the XIV element from the prototype strain SC792. This unique subtype comprised remnants from various mobile genetic elements that encode antimicrobial resistance genes, ultimately forming a large MDR region. Genome analysis of CC398 strain SKLX61416 revealed the presence of a novel 50 kb composite SCCmec with two distinct domains, carrying the ccr gene complexes 5/8 and containing genes for the detoxification of arsenic and sulphide. Further sequence analysis disclosed that 44.23% (23/52) of ST88 strains in our collection carried a lineage-specific pseudo-SCCmec, termed ΨSCCmecST88. This ΨSCCmecST88 harboured the mec gene complex C2, along with a series of genes associated with heavy metal resistance, but lacked an approximately 28 kb region encompassing the ccr gene complex.

Conclusions

Our findings provide evidence for the ongoing evolution of SCCmec elements within the CC398 and ST88 clones, underscoring the need for further surveillance to understand the biological significance of these elements.
Disinfection by-products in drinking water and risk of colorectal cancer: a population-based cohort study
Authors: Helte Emilie , Säve-Söderbergh Melle , Larsson Susanna C , Martling Anna , Åkesson Agneta
Published: August 2023

Background

Colorectal cancer is the third most common malignancy worldwide and is strongly linked to lifestyle and environmental risk factors. Although several drinking-water disinfection by-products are confirmed rodent carcinogens, the evidence in humans for carcinogenicity associated with these by-products, including colorectal cancer, is still inconclusive.

Methods

We assessed the association of long-term exposure to trihalomethanes (THMs), the most prevalent disinfection by-products in chlorinated drinking water, with incidence of colorectal cancer in 58 672 men and women in 2 population-based cohorts. Exposure was assessed by combining long-term information of residential history with drinking water–monitoring data. Participants were categorized according to no exposure, low exposure (<15 µg/L), and high exposure (≥15 µg/L). Incident cases of colorectal cancer were ascertained by use of the Swedish National Cancer Register.

Results

During an average follow-up of 16.8 years (988 144 person-years), 1913 cases of colorectal cancer were ascertained (1176 cases in men and 746 in women, respectively). High THM concentrations in drinking water (≥15 µg/L) were associated with increased risk of colorectal cancer in men (hazard ratio = 1.26, 95% confidence interval = 1.05-1.51) compared with no exposure. When subsites were assessed, the association was statistically significant for proximal colon cancer (hazard ratio = 1.59, 95% confidence interval = 1.11 to 2.27) but not for distal colon cancer or rectal cancer. In women, we observed overall no association of THMs with colorectal cancer.

Conclusion

These results add further evidence that disinfection by-products in drinking water may be a possible risk factor for proximal colon cancer in men. This observation was made at THM concentrations lower than those in most previous studies.
The Making of a Gentleman and a Detective: Tales of Crime, Respectability, and Surveillance from a Colonial Metropolis
Authors: Ghosh Anindita
Published: August 2023

Priyanath Mukhopadhyay (also referred to as PM subsequently) enjoyed an extraordinary career in the colonial police force in Calcutta, where he served as a detective from 1878 to 1911. In his later life, he wrote as a bhadralok and a detective—both important parts of his fashioned self-identity—using narratives of crime to showcase his rare professional expertise and his responsibilities as a cultured upholder of the law. Through an examination of Priyanath’s serialized police tales, it is possible to see how crime writing forged the values of respectability and civic sensibilities, and shaped the moral fiber of an urban society that appeared to be falling apart at its seams. Examining criminal activities in colonial Calcutta as recoverable from PM’s writings affords glimpses of a city being reordered by its material wealth, social aspirations, and moral attitudes. PM’s tales attempt to face this challenge by forging a moral authority in the finely calibrated colonial order. His readers too were evidently invested in it as they endorsed this stand with their purse, leading to soaring circulation figures. The middle classes of Calcutta emerge in these tales as part and parcel of Priyanath’s policing, providing neighborhood and community surveillance networks and backing up the efforts of their detective hero. PM wrote very much as a social commentator as well as a police officer, reaffirming traditional social and domestic values, and frowning upon transgression of class and gender boundaries. What also comes alive is the city itself—the spaces laid bare or concealed by crime—the writing providing access to different topographies of urban knowledge and information networks.
Promoter deletion in the soybean Compact mutant leads to overexpression of a gene with homology to the C20-gibberellin 2-oxidase family
Authors: Liu Xing , Wickland Daniel P , Lin Zhicong , Liu Quilin , Dos Santos Lucas Borges , Hudson Karen A , Hudson Matthew E
Published: August 2023

Height is a critical component of plant architecture, significantly affecting crop yield. The genetic basis of this trait in soybean remains unclear. In this study, we report the characterization of the Compact mutant of soybean, which has short internodes. The candidate gene was mapped to chromosome 17, and the interval containing the causative mutation was further delineated using biparental mapping. Whole-genome sequencing of the mutant revealed an 8.7 kb deletion in the promoter of the Glyma.17g145200 gene, which encodes a member of the class III gibberellin (GA) 2-oxidases. The mutation has a dominant effect, likely via increased expression of the GA 2-oxidase transcript observed in green tissue, as a result of the deletion in the promoter of Glyma.17g145200. We further demonstrate that levels of GA precursors are altered in the Compact mutant, supporting a role in GA metabolism, and that the mutant phenotype can be rescued with exogenous GA3. We also determined that overexpression of Glyma.17g145200 in Arabidopsis results in dwarfed plants. Thus, gain of promoter activity in the Compact mutant leads to a short internode phenotype in soybean through altered metabolism of gibberellin precursors. These results provide an example of how structural variation can control an important crop trait and a role for Glyma.17g145200 in soybean architecture, with potential implications for increasing crop yield.