bluuebunny/crossref_metadata_2025 huggingface dataset:
Electromagnetic Testing System for Measurement of Low Conductivity Objects
Authors: Chen Guang , Li Jichao , Zhou Ke , Li Tianya
Published: October 2023

Electromagnetic testing technology has been widely adopted in industrial process parameter detection, biomedical engineering and other fields due to its fast response, non-contact, non radiation and low cost features. However, measurement of low conductivity objects has always been considered a challenge in the field of electromagnetic testing, due to factors such as low signal sensitivity and data processing complexity, etc. An electromagnetic testing system is presented in this paper, which achieves the detection and extraction of electrical characteristic parameters of low conductivity objects by optimizing sensors, increasing operating frequency, improving effective data transmission and processing etc. Its performance is verified through imaging experiments.
Performance Analysis of Boiling Drying Granulator Cutting Spraying Assisted Wind Field
Authors: Qiao Jibing , Sha Yufeng , Meng Zhaoxin , Liu Jinhui
Published: October 2023

Through computational fluid dynamics (CFD) analysis, the research focused on the influence of fish-scale hole structure and porosity on the airflow uniformity within a cutting and spraying form fluidized bed drying granulator. By optimizing the airflow distribution through simulation calculations, the overall performance of the granulator was improved, leading to enhanced drying efficiency and reduced energy consumption. Furthermore, a comprehensive understanding of the complex airflow patterns and turbulence characteristics within the granulator was gained, facilitating the identification of factors impacting airflow uniformity, such as the structural design and opening rates of the fish-scale hole structure. This knowledge contributed to the development of effective process control and optimization strategies. The research findings demonstrated that the best internal airflow uniformity was achieved when the fish-scale holes had a width of 21mm, a hole height of 3mm, and an overall porosity of 8.4%, or a width of 24mm, a hole height of 2.5mm, and an overall porosity of 8.0%. These results provide guidance for achieving better product outcomes in industrial applications.
Numerical Analysis of a Novel Rotating Piston Blood Pump Based on CFD
Authors: Dong Dianjin , Jiang Jing , Li Dongmei
Published: October 2023

Currently, centrifugal and roller pumps are primarily used as ECMO blood pumps, but their high pressure or high shear force may lead to complications such as hemolysis and platelet activation. Thus, a new blood pump structure was designed by improving the rotating piston pump and applying it to the blood pump. The blood pump flow field was simulated using CFD simulation software to ensure that this pump can produce pulsatile blood flow and guarantee good distribution of flow velocity, pressure, and shear stress in the blood pump. The hemolysis value of the pump was calculated using the Lagrangian particle tracking method. The research results demonstrate that this pump has excellent hemodynamic performance and that most of the shear stresses are less than 100 Pa, as well as a small hemolysis index. Furthermore, the pump combines the advantages of pulsatile and non-pulsatile pumps. This newly developed pump is expected to provide a new direction for ECMO blood pump development and provides important evidence for further optimization and performance evaluation of rotating piston blood pumps.
Study on the Photocatalytic Degradation of Tetracycline Using SrBi4Ti4O15 Nano Photocatalyst Prepared by Electrospinning Method
Authors: Wang Kai , Yu Xiaojiao , Liu Zongbin , Guo Xingru , Zhang Ting , Niu Jinfen , Yao Binhua
Published: October 2023

In this work, an efficient SrBi4Ti4O15 photocatalyst has been successfully synthesized by the electrospinning method. The photocatalytic activity of SrBi4Ti4O15 was estimated by TC as a simulated pollutant. The results of photocatalytic degradation experiments show that the factors such as catalyst dosage, initial concentration, inorganic salts, and water source can all affect the degradation efficiency of SrBi4Ti4O15 on TC. The active species capture test confirmed that h+ and •O2
- play a key role in the TC degradation progress. This work proposed a new direction for designing efficient catalysts for water pollution treatment using solar energy.
Preparation and Performance Evaluation of Quaternary Ammonium Cationic Clay Stabilizer for Oilfield Use
Authors: Xiao Sa , Lin Haonan , Peng Xuefei , Zhao Xing , Wang Gui
Published: October 2023

Acidizing is a crucial technique in the development of low permeability reservoirs in offshore oil fields. The introduction of acid into the formation can lead to the degradation of the clay mineral structure, causing the expansion and migration of clay particles that obstruct the flow of acid channels. The addition of a clay stabilizer with excellent properties can prevent the hydration and expansion of clay, as well as recover damage caused by long-term acidification, such as expansion, dispersion, and migration. To achieve this, the dendritic quaternary ammonium salt ZS-A was synthesized through a quaternization reaction, and subsequently used to develop the clay stabilizer ZSFP. In this study, the properties of clay stabilizer were investigated, including anti-swelling, acid and alkali resistance, water washing resistance, mudstone loss rate, and permeability retention. The results demonstrate that the ZSFP clay stabilizer performs well in terms of anti-swelling, acid-base compatibility, water washing resistance. This clay stabilizer can effectively reduce water-sensitive damage to the reservoir and protect it during acidizing operations.
Equipment layout modeling method for forging lines based on equipment profile layering method
Authors: Zhang Nan , Yuan Chao , Ding Xiaoyue , Zhang Hao , Liu Qingsheng
Published: October 2023

Forging equipment is equipped with an access platform with a size that significantly differs from that of the equipment body, so modeling methods such as envelopes and sequence pairs cannot be used to accurately describe the equipment or layout. In this paper, we propose a profile layering method for forging equipment, and establish a model of production line layout by setting a layering level using the Cartesian coordinate system, so as to lay a foundation for the subsequent research on interference detection, layout optimization and trajectory planning for production lines.
Fracture failure analysis of 5 “drill collar double shoulder external thread in a well
Authors: Hongtao Liu , Fangting Hu , Mifeng Zhao , Jialei Chen , Xianren Kuang , Tao Zhang , Zhengkai Shang
Published: October 2023

This article analyzes a well using 5 “Based on the analysis of the chemical composition of the drill collar, mechanical property testing, metallographic structure analysis, fracture morphology and energy spectrum analysis, as well as the analysis of the stress, bending strength ratio, and double shoulder structure of the drill collar, combined with the deviation of the well section where the drill collar fracture occurred and the drilling pressure during drilling, it is clear that the main reason for the failure of the drill collar is that there is a large well deviation in the area and the drilling pressure is not properly reduced, resulting in The drill collar undergoes severe bending alternating stress and initiates fatigue cracks and propagates at the root of 1-2 threads at the large end of the external thread.
Characterisation of impact resistance of composite reinforced by hybridised carbon-flax fibres in polyfurfuryl alcohol resin
Authors: Lu Yiling , Pawlik Marzena , Ganapathi Shishira P , Wood Paul , Gunputh Urvashi , Le Huirong
Published: October 2023

Research on polyfurfuryl alcohol (PFA) bioresin has increased due to its unique flame-retardant property. This study utilised the hybridisation of carbon and flax fibres in combination with PFA resin to make fibre-reinforced polymer (FRP) composites. The samples were tested for low-velocity impact at an energy of 20 Joules. Results showed that the fibres-hybridised PFA-based sample had higher energy absorption compared to the carbon-fibre only sample. More importantly, the hybridised sample retained almost the same amount of flexural modulus after impact, while carbon fibre only FRP sample lost more than 20% of its flexural modulus. This highlights the benefits of hybridisation in impact resistance and retention of mechanical properties post-impact in the presence of PFA resin, which is consistent with previous reports of epoxy-based FRP composites. In conclusion, the combination of fibre hybridisation and PFA bioresin presents a promising solution to meet strict flame-retardant requirements, impact resistance needs, and reduce environmental carbon footprint for engineering applications.
Determination of the ignorable boundary condition and standard sample for a novel in-situ dynamic mechanical analysis method on soft matter
Authors: Wu Longyan , Tang Lisheng , Huang Ran
Published: October 2023

An in-situ Dynamic Mechanical Analysis (DMA) method for soft matter developed by our group [Wu. et.al. 2022] encounters the problem of irregular samples, which significantly vary in shape and size in practice, therefore a standard sample “large enough” to ignore the boundary and size effects is necessary to determine the baseline of test and build the correspondence between this new method to classical mechanical tests. In this work, we use finite element analysis to approach the optimal size of a brick sample where the stress on the boundaries in three spatial directions are ignorable, and certified the results by testing a series of silicone gel samples on the in-situ DMA device. The stress-strain of tensile and compression are characterized. The material properties of gel are chosen to be close to the biological soft tissue. The size of 40mm(L)×40mm(W)×20mm(H) is determined to be the optimal result.
Edge Thomson scattering diagnostic with compact polychromators on the HL-3 Tokamak
Authors: Gong S.B. , Zhang T.C. , Guo W.P. , Hou Z.P. , Zhai W.Y. , Liu C.H. , Deng B.H. , Shi Z.B. , Chen W. , Zhong W.L. , Xu M. , Duan X.R.
Published: October 2023

The edge Thomson scattering (ETS) diagnostic with compact polychromators on the HL-3
Tokamak was developed recently. The energy and repetition frequency of the Nd: YAG laser are 2.0 J
and 30 Hz, respectively. The laser beam propagates vertically through the plasma region and the
scattered light is observed horizontally. The projected scattering region at the plasma midplane
is from 0.6 < r/a < 1.0. The 5-channel compact polychromator (width 432 mm, depth 472 mm
and height 88 mm) is developed to measure the Thomson scattering spectra. Modular design in the
power supply and the amplifier circuits simplifies the assembly and maintenance of the
polychromator. By using the new narrow band filters with cut-off depth larger than OD 4, the stray
light resulted from Nd: YAG laser has been suppressed by the polychromator. The signal to noise
ratio (SNR) range of each channel is from 10 to 200 depending on plasma parameters. The designed
electron temperature measurement range is from 5 to 1000 eV and electron density measurement range
is from 5 × 1018 to 1 × 1020 m-3. New measurement results of electron
temperature by ETS are compared with that from the electron cyclotron emission (ECE)
radiometer. The time evolution of ETS and ECE matches with each other in different plasma
discharges. Combined with the data from the core Thomson scattering diagnostic system, the plasma
electron temperature profile on the HL-3 tokamak is presented for the first time.
Note on intrinsic resolution in liquid organic scintillators
Authors: Smirnov O.
Published: October 2023

Fluctuations in photon production in scintillator could
contribute to the total energy resolution of a scintillation
detector. This contribution, called intrinsic resolution (IR), is
one of the factors limiting the total energy resolution in detectors
based on liquid organic scintillators (LSs). There are very few
experimental measurements of the IR in LSs available, and the
underlying physics is not completely understood. We propose a
phenomenological description of IR of LSs and systematize the data
available using a single universal parameter that characterizes
IR. We show that all experimental data within the model
demonstrate the presence of extra smearing of energy resolution due
to IR with a typical value of ≃ 2% at 1-MeV energy
release. The model can be used to simulate the effect of IR in
LS-based detectors.
A decoupled Bayesian method for snake robot control in unstructured environment
Authors: Jia Yuanyuan , Ma Shugen
Published: October 2023

This paper presents a method which avoids the common practice of using a complex coupled snake robot model and performing kinematic analysis for control in cluttered environments. Instead, we introduce a completely decoupled dynamical Bayesian formulation with respect to interacted snake robot links and environmental objects, which requires much lower complexity for efficient and robust control. When a snake robot does not interact with obstacles, it runs by a simple serpenoid controller. However, when it exhibits interaction with environments, defined as close proximity or collision with targets and/or obstacles, we extend the conventional Bayesian framework by modeling such interactions in terms of stimuli. The proposed ‘multi-neural-stimulus function’ represents the cumulative effect of both external environmental influences and internal constraints of the snake robot. It implicitly handles the ‘unexpected collision’ problem and thus solve the difficult data association and shape adjustment problems for snake robot control in an innovative way. Preliminary experimental results have demonstrated promising performance of the proposed method comparing with the state-of-the-art.
Exact sharp-fronted solutions for nonlinear diffusion on evolving domains
Authors: Johnston Stuart T , Simpson Matthew J
Published: October 2023

Models of diffusive processes that occur on evolving domains are frequently employed to describe biological and physical phenomena, such as diffusion within expanding tissues or substrates. Previous investigations into these models either report numerical solutions or require an assumption of linear diffusion to determine exact solutions. Unfortunately, numerical solutions do not reveal the relationship between the model parameters and the solution features. Additionally, experimental observations typically report the presence of sharp fronts, which are not captured by linear diffusion. Here we address both limitations by presenting exact sharp-fronted solutions to a model of degenerate nonlinear diffusion on a growing domain. We obtain the solution by identifying a series of transformations that converts the model of a nonlinear diffusive process on an evolving domain to a nonlinear diffusion equation on a fixed domain, which admits known exact solutions for certain choices of diffusivity functions. We determine expressions for critical time scales and domain growth rates such that the diffusive population never reaches the domain boundaries and hence the solution remains valid.
Symmetry structure of integrable hyperbolic third order equations
Authors: Rasin Alexander G , Schiff Jeremy
Published: October 2023

We explore the application of generating symmetries, i.e. symmetries that depend on a parameter, to integrable hyperbolic third order equations, and in particular to consistent pairs of such equations as introduced by Adler and Shabat in (2012 J. Phys. A: Math. Theor.
45 385207). Our main result is that different infinite hierarchies of symmetries for these equations can arise from a single generating symmetry by expansion about different values of the parameter. We illustrate this, and study in depth the symmetry structure, for two examples. The first is an equation related to the potential KdV equation taken from (Adler and Shabat 2012 J. Phys. A: Math. Theor.
45 385207). The second is a more general hyperbolic equation than the kind considered in (Adler and Shabat 2012 J. Phys. A: Math. Theor.
45 385207). Both equations depend on a parameter, and when this parameter vanishes they become part of a consistent pair. When this happens, the nature of the expansions of the generating symmetries needed to derive the hierarchies also changes.
Growth of aligned and twisted hexagonal boron nitride on Ir(110)
Authors: Michely Thomas , Bergelt Jason , Safeer Affan , Bäder Alexander , Hartl Tobias , Fischer Jeison
Published: October 2023

The growth of monolayer hexagonal boron nitride (h-BN) on Ir(110) through low-pressure chemical vapor deposition is investigated using low energy electron diffraction and scanning tunneling microscopy. We find that the growth of aligned h-BN on Ir(110) requires a growth temperature of 1500 K, whereas lower growth temperatures result in coexistence of aligned h-BN with twisted h-BN. The presence of the h-BN overlayer suppresses the formation of the nano-faceted ridge pattern known from clean Ir(110). Instead, we observe the formation of a

(
1
×
n
)

reconstruction, with n such that the missing rows are in registry with the h-BN/Ir(110) moiré pattern. Our moiré analysis showcases a precise methodology for determining both the moiré periodicity and the h-BN lattice parameter on an fcc(110) surface. Aligned h-BN on Ir(110) is found to be slightly compressed compared to bulk h-BN, with a monolayer lattice parameter of

a

h
−
B
N

=
(
0.2489
±
0.0006
)

 nm. The lattice mismatch with the substrate along

1

1
ˉ

0

gives rise to a moiré periodicity of

a

m

=
2.99
±
0.08

 nm.
Extracting mechanical and microstructural properties of Cu–Zr thin film alloys by MEMS, AFM and ellipsometer
Authors: Alarifi Nahed , Al-Gawati Mahmoud A , Alnjiman Fahad , Albrithen Hamad , Alodhayb Abdullah N
Published: October 2023

The quantification of the atomic concentration ratios of thin-film metallic alloys having low atomic ordering is challenging, particularly if they are grown on similar metals and possess different surface chemistries. Micromechanical and optical methods have been used to correlate the elemental ratios with the mechanical and optical properties of the films. The room-temperature growth of Cu–Zn thin-film alloys with varying elemental ratios on cosputtered Si substrates was performed to obtain an amorphous film structure. X-ray diffraction patterns confirmed that the grown films exhibited a very short range ordering, suggesting an amorphous structure. The mechanical properties of the films evaluated using microelectromechanical system (MEMS) indicated that the alloy films with moderate Zr concentrations had lower surface stress compared to those with low and high Zr concentrations. Furthermore, spectroscopic ellipsometry was employed to qualitatively assess the relaxation times of free carriers. The results demonstrated a strong correlation between the relaxation times and surface roughness measurements, showing that the microstructure and resistivity characteristics of the alloys align with the Nordheim semiempirical model. The extinction coefficient of the binary alloy film linearly depends on the metallic bulk concentration ratio in a specific metallic ratio range, paving the way for realizing qualitative elemental percentage assessment in the field of metrology.
Solid solution softening at room temperature and hardening at elevated temperatures: a case by minor Mn addition in a (HfNbTi)85Mo15 refractory high entropy alloy
Authors: Li Xiaolong , Ding Mao , Hu Qiang , Liu Zhiyuan , Mao Huahai , Guo Sheng
Published: October 2023

To address the conflict between room-temperature (RT) ductility and high-temperature (HT) strength in single phase bcc-structured refractory high entropy alloys, here we propose to use minor alloying to achieve solid solution softening at RT and simultaneously, solid solution hardening at HT. Our strategy was manifested by minor Mn additions in a RT brittle (HfNbTi)85Mo15 refractory high entropy alloy, where nominal Mn additions ranging from 2 at. % down to 0.03 at. % were seen to soften the base (HfNbTi)85Mo15 alloy at RT, while to harden the base alloy at the temperature range from 400 to 800 °C. The yield stress in all studied alloys showed a three-stage pattern, characterized by a temperature dependent stage at temperatures below 400 °C, followed by a temperature independent stage at intermediate temperatures ranging from 400 to 800 °C, and finally another temperature dependent stage at temperatures higher than 800 °C. The mechanisms for solid solution softening and solid solution hardening in single phase bcc-structured refractory high entropy alloys were discussed, together with their temperature dependence.
Effect of intercritical quenching soaking time on cryogenic toughness and internal friction characterization of 9Ni steel
Authors: Wang Dihe , Pang Qihang , Cui Juan , Li Weijuan , Du Lin , Lu Guangsheng
Published: October 2023

Quenching, intercritical quenching and high-temperature tempering of 9Ni steel is widely used in large-size and high-capacity liquefied natural gas storage tanks due to its excellent mechanical properties at low temperatures. This paper studied the microstructure, internal friction and mechanical properties of different intercritical quenching heat soaking times on the cryogenic toughness of 9Ni steel. The effect of martensitic strip thickness change on thermal stability and morphology of reversed austenite after intercritical quenching heat soaking time of 9Ni steel was revealed. The findings show that the thickness of the martensitic slats increases by 4.5μm when the intercritical quenching of steel is conducted for 50 min, and the maximum concentration of Ni and Mn reaches 13.5% and 10.25%, respectively. The volume fraction of thin film reversed austenite is about 5%. Different frequency under the condition of isothermal Snoek-Kê-Köster peak changes shows there will be a loss of mechanical energy in the process of phase transition. They are important factors for the maximum volume fraction of 9Ni steel film reversed austenite and the significant improvement of cryogenic toughness.
Measurement of web tension using ambient vibrations in roll-to-roll manufacturing of flexible and printed electronics
Authors: Feng Dan , Morrison Neil , Armstrong Claire , Moyers Ken , Raman Arvind , Wagner Ryan B
Published: October 2023

Web tension measurement and control are important for the quality control of flexible and printed electronics fabricated by roll-to-roll (R2R) manufacturing. The distribution of tension within a R2R web can be calculated from the values of the web’s mechanical resonance frequencies. Typically, such measurements require an active external forcing to be generated and applied to the web. In this work, we show it is possible to obtain the web’s resonance frequencies from forcing due to ambient noise present in the test environment. This result broadens the applicability of noncontact resonance methods for computing web tension as currently available methods of active external forcing cannot be applied to all web materials and all R2R operating environments. We validate the ambient excitation method by comparing it to speaker-based acoustic excitation at atmospheric pressure and find the two methods agree within 0.5%. A calculation of the experimental motion of the web due to finite temperature effects suggests the observed vibration is generated from air-borne or structure-borne noise in the test environments. To show the effectiveness of the approach, we demonstrate the use of ambient excitation at five externally applied tensions, on three different web materials, and at both atmospheric and vacuum pressures.
A new method that automatically regularizes scattering amplitudes
Authors: Prabhu Nagabhushana
Published: October 2023

We present a new regularization procedure called autoregularization. The new procedure regularizes the divergences, encountered previously in a scattering process, using the intrinsic scale of the process. We use autoregularization to calculate the amplitudes of several scattering processes in QED and compare the calculations with experimental measurements over a broad range of center-of-momentum energies (≲MeV to ≳200 GeV). The calculated amplitudes are found to be in good agreement with experimental data.
1

1

Specifically, the O(α) correction to electron’s gyromagnetic ratio predicted by autoregularization agrees with experimental measurement to within 0.06% (Section 3.1), which is to be compared to Schwinger’s O(α) correction which agrees with experimental measurement to within 0.15%; the O(α) estimate of the Lamb shift predicted by autoregularization agrees with the experimental measurements to within 0.33% (section 3.2); the running fine structure constant predicted by autoregularization at O(α) agrees with the prediction of cutoff regularization to within 0.8% over one to four orders of magnitude above the electron’s mass scale (section 3.3); the tree-level prediction of autoregularization for Compton scattering is in better agreement with experimental data than the prediction of the well-known Klein-Nishina formula by about 4.02% (section 3.5.1); the tree-level predicition of autoregularization for pair annihilation at center-of-momentum energy of 206.671 GeV agrees with the experimental data about 0.67 % better than the prediction of the standard QED (section 3.5.2).

To test autoregularization in a non-Abelian gauge theory, we calculate the QCD coupling constant at 1-loop and show that, like the known regularization schemes, autoregularization also predicts asymptotic freedom in QCD. Finally, we show that the vacuum energy density of the free fields in the Standard Model, calculated using autoregularization, is smaller than the current estimate of the cosmic critical density.
RSM modelling and optimization for performance evaluation of biodiesel production process from livistona jenkinsiana using NaOH as a catalyst
Authors: Ahamed Moiching Sajit , Lingfa Pradip , Chandrasekaran Muthumari
Published: October 2023

The production of biodiesel from conventional vegetable oils is limited by the high cost and competition with food supply. Therefore, there is a need to explore new and underutilized feedstocks that can provide abundant and low-cost oil for biodiesel production. Livistona jenkinsiana is a palm species that grows in tropical and subtropical regions of Asia. It produces oil-rich fruits that are usually discarded as waste. In this work, biodiesel was produced from Livistona jenkinsiana through transesterification reaction, and the parametric analysis was carried out. The process parameters such as reaction temperature, molar ratio, reaction time, and catalyst amount were studied, and yield (Y) was modelled using response surface methodology (RSM) as a modelling tool in MINITAB@17.1.0 software. A second-order RSM model for biodiesel yield was developed as a function of temperature, catalyst, and the molar ratio, which could predict the biodiesel yield. ANOVA results showed that temperature, catalyst, and molar ratio played an important role in the transesterification process. The optimization result showed that the optimal conditions were attained at a temperature of 61.78 °C, methanol to oil molar ratio 9.25:1, and catalyst concentration of 0.86 wt%. The highest biodiesel yield predicted was 94.47%. The reaction was carried out at a constant reaction speed of 500 rpm for 1.5 h of reaction time. The physicochemical properties of the produced biodiesel indicate that the biodiesel from Livistona jenkinsiana oil (LJO) is ideal for the production of biodiesel.
Run-of-river hydropower in the UK and Ireland: the case for abstraction licences based on future flows
Authors: Dallison Richard J H , Patil Sopan D
Published: October 2023

Run-of-river hydropower in the United Kingdom (UK) and Ireland is a small but vital component of renewable electricity generation that enhances grid diversification and resilience, contributes to the net-zero emissions targets, and provides local community benefits. Planning approval by environmental regulators for hydropower water abstraction is based on the abstraction licence conditions (ALCs) that dictate when and how much water may be taken from a given stream location. Although ALCs for non-environmentally sensitive rivers vary across England, Wales, Scotland, Northern Ireland, and Ireland, the impacts of these variations on power generation are not fully understood. Here, we investigate how ALC variations across the UK and Ireland have historically impacted water abstraction and power generation and might continue to do so under future climate conditions. Specifically, we apply five distinct ALCs combination sets, as laid out by the five environmental regulators in the region, to historical observed streamflows and future projected flows (modelled for the Representative Concentration Pathway 8.5 scenario using the EXP-HYDRO hydrological model), at 531 hydropower sites across the UK and Ireland. We then calculate the daily water abstraction potential for each hydropower site and the collective power generation potential separately for Great Britain (GB) and the Island of Ireland (IoI). Our results show that the ALCs that permit greater use of lower flows allow for more power generation than those that enable abstraction during high flow conditions. The most optimal combination of ALCs for power generation, when compared to those currently in use, increases future generation potential by 30.4% for GB and 24.4% for the IoI, while maintaining environmental protection as per the Welsh guidelines. Our results suggest that ALC policy and regulatory reforms are needed to provide optimal use of future streamflows for hydropower generation while ensuring protection for the environment is maintained.
CLT-seq as a universal homopolymer-sequencing concept reveals poly(A)-tail-tuned ncRNA regulation
Authors: Su Qiang , Long Yi , Wang Jun , Gou Deming
Published: October 2023

Dynamic tuning of the poly(A) tail is a crucial mechanism for controlling translation and stability of eukaryotic mRNA. Achieving a comprehensive understanding of how this regulation occurs requires unbiased abundance quantification of poly(A)-tail transcripts and simple poly(A)-length measurement using high-throughput sequencing platforms. Current methods have limitations due to complicated setups and elaborate library preparation plans. To address this, we introduce central limit theorem (CLT)–managed RNA-seq (CLT-seq), a simple and straightforward homopolymer-sequencing method. In CLT-seq, an anchor-free oligo(dT) primer rapidly binds to and unbinds from anywhere along the poly(A) tail string, leading to position-directed reverse transcription with equal probability. The CLT mechanism enables the synthesized poly(T) lengths, which correspond to the templated segment of the poly(A) tail, to distribute normally. Based on a well-fitted pseudogaussian-derived poly(A)-poly(T) conversion model, the actual poly(A)-tail profile is reconstructed from the acquired poly(T)-length profile through matrix operations. CLT-seq follows a simple procedure without requiring RNA-related pre-treatment, enrichment or selection, and the CLT-shortened poly(T) stretches are more compatible with existing sequencing platforms. This proof-of-concept approach facilitates direct homopolymer base-calling and features unbiased RNA-seq. Therefore, CLT-seq provides unbiased, robust and cost-efficient transcriptome-wide poly(A)-tail profiling. We demonstrate that CLT-seq on the most common Illumina platform delivers reliable poly(A)-tail profiling at a transcriptome-wide scale in human cellular contexts. We find that the poly(A)-tail-tuned ncRNA regulation undergoes a dynamic, complex process similar to mRNA regulation. Overall, CLT-seq offers a simplified, effective and economical approach to investigate poly(A)-tail regulation, with potential implications for understanding gene expression and identifying therapeutic targets.
sTREM2 is associated with attenuated tau aggregate accumulation in the presence of amyloid-β pathology
Authors: Nabizadeh Fardin
Published: October 2023

Triggering Receptor Expressed on Myeloid Cell 2 (TREM2) plays a crucial role in the transition of microglia from a state of homeostasis to a state associated with the disease. Mutations in TREM2 are strongly linked with a higher risk of developing neurodegenerative diseases, including Alzheimer’s disease. There have been contradictory findings regarding the potential detrimental or protective effects of microglial activation and TREM2-related microglial responses in Alzheimer’s disease. Although previous studies reported increased CSF soluble TREM2 (sTREM2) in different clinical stages of Alzheimer’s disease, the exact association between Alzheimer’s disease hallmarks such as amyloid-beta and tau pathology remains unclear. In the present study, I aimed to investigate the association between TREM2-related microglial responses and tau accumulation in the presence and absence of amyloid-beta pathology in order to give a better view of the role of microglial activation in Alzheimer’s disease development. Imaging data of 178 non-demented participants including 107 amyloid-beta-negative participants, 71 amyloid-beta-positive were recruited from Alzheimer’s disease Neuroimaging Initiative. The CSF sTREM2 was used as an in vivo indicator of microglial responses associated with TREM2. Furthermore, I used longitudinal tau-PET and resting-state functional MRI connectomes in order to investigate the association of TREM2-related microglial activation and tau spreading through functional connections. A higher level of sTREM2 was associated with slower tau aggregate accumulation in non-demented amyloid-beta-positive. Furthermore, measuring the tau spreading through inter-connected regions using functional MRI connectomes confirms that the TREM2-related microglial activity might be a protective factor against tau pathology in brain tissue. These findings demonstrate that in individuals with initial amyloid-beta abnormalities, TREM2-related microglial activation is linked to reduced regional accumulation of tau aggregates and also, spreading across inter-connected brain regions, as evaluated through functional MRI connectomes during the early stages of Alzheimer’s disease.
High-rate leading spikes in propagating spike sequences predict seizure outcome in surgical patients with temporal lobe epilepsy
Authors: Shamas Mohamad , Yeh Hsiang J , Fried Itzhak , Engel Jerome , Staba Richard J
Published: October 2023

Inter-ictal spikes aid in the diagnosis of epilepsy and in planning surgery of medication-resistant epilepsy. However, the localizing information from spikes can be unreliable because spikes can propagate, and the burden of spikes, often assessed as a rate, does not always correlate with the seizure onset zone or seizure outcome. Recent work indicates identifying where spikes regularly emerge and spread could localize the seizure network. Thus, the current study sought to better understand where and how rates of single and coupled spikes, and especially brain regions with high-rate and leading spike of a propagating sequence, informs the extent of the seizure network.

In 37 patients with medication-resistant temporal lobe seizures, who had surgery to treat their seizure disorder, an algorithm detected spikes in the pre-surgical depth inter-ictal EEG. A separate algorithm detected spike propagation sequences and identified the location of leading and downstream spikes in each sequence. We analysed the rate and power of single spikes on each electrode and coupled spikes between pairs of electrodes, and the proportion of sites with high-rate, leading spikes in relation to the seizure onset zone of patients seizure free (n = 19) and those with continuing seizures (n = 18). We found increased rates of single spikes in mesial temporal seizure onset zone (ANOVA, P < 0.001, η2 = 0.138), and increased rates of coupled spikes within, but not between, mesial-, lateral- and extra-temporal seizure onset zone of patients with continuing seizures (P < 0.001; η2 = 0.195, 0.113 and 0.102, respectively). In these same patients, there was a higher proportion of brain regions with high-rate leaders, and each sequence contained a greater number of spikes that propagated with a higher efficiency over a longer distance outside the seizure onset zone than patients seizure free (Wilcoxon, P = 0.0172). The proportion of high-rate leaders in and outside the seizure onset zone could predict seizure outcome with area under curve = 0.699, but not rates of single or coupled spikes (0.514 and 0.566). Rates of coupled spikes to a greater extent than single spikes localize the seizure onset zone and provide evidence for inter-ictal functional segregation, which could be an adaptation to avert seizures. Spike rates, however, have little value in predicting seizure outcome. High-rate spike sites leading propagation could represent sources of spikes that are important components of an efficient seizure network beyond the clinical seizure onset zone, and like the seizure onset zone these, too, need to be removed, disconnected or stimulated to increase the likelihood for seizure control.
Development and assessment of a novel integrated system powered by parabolic trough collectors for combined power, heating and freshwater production
Authors: Siddiqui Mohd Asjad , Almatrafi Eydhah
Published: October 2023

Hybrid solar-based integrated systems represent a viable solution for countries with abundant solar radiation, as they provide energy needs in an environmentally friendly way, offering a sustainable and economically advantageous energy solution that utilizes a free source of energy. Therefore, this research offers a thermodynamic evaluation of a novel integrated system driven by solar energy that aims to produce power, heating and freshwater. The integrated system consists of a parabolic trough collector that uses CO2 as its working fluid and implements the supercritical carbon dioxide cycle to generate power and heating. The integrated system also includes an adsorption desalination system with heat recovery between the condenser and evaporator, which employs a cutting-edge material called an aluminium fumarate metal–organic framework to produce fresh water. For the modelling of a novel system, an engineering equation solver, which is considered a reliable tool for thermodynamic investigations, is employed. The effectiveness of an integrated system is evaluated using a mathematical model and different varying parameters are examined to ascertain their influence on thermal and exergy efficiency, specific daily water production and gained output ratio. The results revealed that the parabolic trough collector achieved a thermal efficiency of 67.2% and an exergy efficiency of 41.2% under certain conditions. Additionally, the thermal efficiencies for electrical and heating were obtained 24.68% and 9.85%, respectively. Finally, the specific daily water production was calculated, showing promising results and an increase from 7.1 to 12.5 m3/ton/day, while the gain output ratio increased from 0.395 to 0.62 when the temperature of hot water increased from 65°C to 85°C, under the selected conditions.
A case of a patient with cutaneous ‘frog spawn’
Authors: Hynes Jason , Aretz Nicholas Kruseman , McCartney Yvonne , Eustace Karen
Published: October 2023

A 60-year-old woman presented with a 7-year history of an erythematous cutaneous eruption involving the right submammary area. She described asymptomatic, small blisters that would exude clear fluid intermittently.
Extracorporeal life support in cardiac arrest: a post hoc Bayesian re-analysis of the INCEPTION trial
Authors: Heuts Samuel , van de Koolwijk Anina F , Gabrio Andrea , Ubben Johannes F H , van der Horst Iwan C C , Delnoij Thijs S R , Suverein Martje M , Maessen Jos G , Lorusso Roberto , van de Poll Marcel C G
Published: October 2023

Aims

Previously, we performed the multicentre INCEPTION trial, randomizing patients with refractory out-of-hospital cardiac arrest (OHCA) to extracorporeal cardiopulmonary resuscitation (ECPR) or conventional cardiopulmonary resuscitation (CCPR). Frequentist analysis showed no statistically significant treatment effect for the primary outcome; 30-day survival with a favourable neurologic outcome (cerebral performance category score of 1–2). To facilitate a probabilistic interpretation of the results, we present a Bayesian re-analysis of the INCEPTION trial.

Methods and results

We analysed survival with a favourable neurologic outcome at 30 days and 6 months under a minimally informative prior in the intention-to-treat population. Effect sizes are presented as absolute risk differences (ARDs) and relative risks (RRs), with 95% credible intervals (CrIs). We estimated posterior probabilities at various thresholds, including the minimal clinically important difference (MCID) (5% ARD), based on expert consensus, and performed sensitivity analyses under sceptical and literature-based priors. The mean ARD for 30-day survival with a favourable neurologic outcome was 3.6% (95% CrI −9.5–16.7%), favouring ECPR, with a median RR of 1.22 (95% CrI 0.59–2.51). The posterior probability of an MCID was 42% at 30 days and 42% at 6 months, in favour of ECPR.

Conclusion

Bayesian re-analysis of the INCEPTION trial estimated a 42% probability of an MCID between ECPR and CCPR in refractory OHCA in terms of 30-day survival with a favourable neurologic outcome.

Trial registration

Clinicaltrials.gov (NCT03101787, registered 5 April 2017).
Complete sternal cleft individualized repair using a 3D-printed polyether ether ketone model: a case report
Authors: Zhang Guangjian , Wang Lei , Dang Peizhu , Yan Yang
Published: October 2023

Background

Bicuspid aortic valve (BAV) is a common anatomical variation that the aortic valve possesses two functional cusps. Sternal cleft is a rare congenital malformation which is caused by failed fusion of sternal bones. Early surgical repair is advised; otherwise, alternative surgical techniques should be performed. Due to their biocompatibility and elasticity, 3D-printed polyether ether ketone (PEEK) implants can be used. Complete sternal cleft coexistence with BAV is infrequent.

Case summary

A 49-year-old man with a 6-month history of paroxysmal shortness of breath and exertional chest tightness presented to our hospital. The man was diagnosed with BAV with severe aortic valve regurgitation and a complete sternal cleft. He underwent aortic valve replacement surgery using the bovine pericardial aortic valve. Concurrently, a 3D-printed PEEK implant surgery was performed to address the sternal cleft. The patient’s postoperative recovery was uneventful.

Discussion

In this case, 3D-printed PEEK implants were used for high biocompatibility and elastic modulus. However, because PEEK material inherently lacks biological activity, enhancing this aspect remains a focal point of clinical research.
CURATE.AI-assisted dose titration for anti-hypertensive personalized therapy: study protocol for a multi-arm, randomized, pilot feasibility trial using CURATE.AI (CURATE.AI ADAPT trial)
Authors: Truong Anh T L , Tan Shi-Bei , Wang Golda Z , Yip Alexander W J , Egermark Mathias , Yeung Wesley , Lee V Vien , Chan Mark Y , Kumar Kirthika S , Tan Lester W J , Vijayakumar Smrithi , Blasiak Agata , Wang Laureen Y T , Ho Dean
Published: October 2023

Aims

Artificial intelligence–driven small data platforms such as CURATE.AI hold potential for personalized hypertension care by assisting physicians in identifying personalized anti-hypertensive doses for titration. This trial aims to assess the feasibility of a larger randomized controlled trial (RCT), evaluating the efficacy of CURATE.AI-assisted dose titration intervention. We will also collect preliminary efficacy and safety data and explore stakeholder feedback in the early design process.

Methods and results

In this open-label, randomized, pilot feasibility trial, we aim to recruit 45 participants with primary hypertension. Participants will be randomized in 1:1:1 ratio into control (no intervention), home blood pressure monitoring (active control; HBPM), or CURATE.AI arms (intervention; HBPM and CURATE.AI-assisted dose titration). The home treatments include 1 month of two-drug anti-hypertensive regimens. Primary endpoints assess the logistical (e.g. dose adherence) and scientific (e.g. percentage of participants for which CURATE.AI profiles can be generated) feasibility, and define the progression criteria for the RCT in a ‘traffic light system’. Secondary endpoints assess preliminary efficacy [e.g. mean change in office blood pressures (BPs)] and safety (e.g. hospitalization events) associated with each treatment protocol. Participants with both baseline and post-treatment BP measurements will form the intent-to-treat analysis. Following their involvement with the CURATE.AI intervention, feedback from CURATE.AI participants and healthcare providers will be collected via exit survey and interviews.

Conclusion

Findings from this study will inform about potential refinements of the current treatment protocols before proceeding with a larger RCT, or potential expansion to collect additional information. Positive results may suggest the potential efficacy of CURATE.AI to improve BP control.

Trial registration number

NCT05376683
Trends in caesarean section rates in Europe from 2015-2019 using Robson's Ten-Group Classification System: A Euro-Peristat registry study
Authors: Amyx M , Philibert M , Farr A , Donati S , Smarason A , Fernandez Elorriaga M , Heller G , Krypianou T , Mierzejewska E , Zile-Velika I
Published: October 2023

Objective

To assess changes in caesarean section (CS) in Europe from 2015-2019 and utilise the Robson Ten Group Classification System (TGCS) to evaluate the contribution of different obstetric populations to overall CS rates and trends

Methods

This was an observational study utilising routine population birth data from 28 European countries participating in the Euro-Peristat network. We included all births ≥22 weeks gestational age, from 2015 to 2019. A federated model used individual-level data from routine sources in each country formatted to common data model to generate anonymous, aggregate data tables on yearly CS rates and the Robson TGCS classification. We computed the Robson group-specific relative size, CS rate, relative and absolute contribution to overall CS rate

Results

Among the 28 European countries, CS rates (2015: 16.0-55.9%; 2019: 16.0-52.2%) and trends varied (-3.7-+4.7%; 9 countries decreasing, 7 stable [ ≤ ±0.2], 12 increasing). Using the Robson Classification (17 countries), in most countries, labour induction increased (Groups 2a, 4a), while multiple pregnancies (Group 8) decreased. In countries with decreasing overall CS rates, CS tended to decrease in most Robson groups, while in countries with increasing overall CS rates, CS tended to increase in most Robson groups. In countries with the greatest increase in CS rates (>1%), absolute contributions of Groups 1 (nulliparous term cephalic singletons, spontaneous labour), 2a and 4a, 2b and 4b (prelabour CS), and 10 (preterm cephalic singletons) to overall CS tended to increase.

Conclusions

Analysis of the Robson Classification shows varying CS trends and rates across Europe. Comparisons between European countries, particularly those with divergent trends, could provide insight into strategies to reduce CS without indication.