bluuebunny/crossref_metadata_2025 huggingface dataset:
The energetics of rapid cellular mechanotransduction
Authors: Young Michael N. , Sindoni Michael J. , Lewis Amanda H. , Zauscher Stefan , Grandl Jörg
Published: February 2023

Cells throughout the human body detect mechanical forces. While it is known that the rapid (millisecond) detection of mechanical forces is mediated by force-gated ion channels, a detailed quantitative understanding of cells as sensors of mechanical energy is still lacking. Here, we combine atomic force microscopy with patch-clamp electrophysiology to determine the physical limits of cells expressing the force-gated ion channels (FGICs) Piezo1, Piezo2, TREK1, and TRAAK. We find that, depending on the ion channel expressed, cells can function either as proportional or nonlinear transducers of mechanical energy and detect mechanical energies as little as ~100 fJ, with a resolution of up to ~1 fJ. These specific energetic values depend on cell size, channel density, and cytoskeletal architecture. We also make the surprising discovery that cells can transduce forces either nearly instantaneously (<1 ms) or with a substantial time delay (~10 ms). Using a chimeric experimental approach and simulations, we show how such delays can emerge from channel-intrinsic properties and the slow diffusion of tension in the membrane. Overall, our experiments reveal the capabilities and limits of cellular mechanosensing and provide insights into molecular mechanisms that different cell types may employ to specialize for their distinct physiological roles.
Effect of fibre orientation and stacking sequence on properties of hybrid composites
Authors: Sakib Sadman , Haque Mohammad Rejaul , Haque M. Merajul , Faruqi Farhana , Ahmed Syed Shaheer Uddin , Hasan Mahbub , Gafur M. A.
Published: February 2023

A novel combination of Borassus Flabellifer Petiole Fibre/Palmyra Palm Petiole Fibre (PP) and Borassus Flabellifer Leaf Stalk Fibre/Palmyra Palm Leaf Stalk Fibre fibres (LS) bonded by vinyl ester is considered as the natural fibre-reinforced hybrid composites. Three-layered composites with various stacking sequences at 30 wt.% fibre loading were studied. Tensile, impact, and hardness properties exhibit increasing trend for different stacking sequences. A maximum increase of 215.8% tensile strength and 310.5% impact strength was observed in the PPLSPP (90/0/90) specimen. The water absorption percentage showed a peak value of 18% and the hardness enhancement was around 75% for the LSPPLS (90/0/90) sample. The Fourier Transform Infrared spectroscopy was performed and Scanning electron micrographs were performed to show the fibre–matrix bonding.
Kate Schroder: Gender equality in STEM
Authors: Van Emmenis Lucie
Published: February 2023

Kate Schroder is a professor and director of the Centre for Inflammation and Disease Research at the Institute for Molecular Bioscience (IMB), University of Queensland, Australia. Her lab, the IMB Inflammasome Laboratory, is interested in the mechanisms that underlie inflammasome activity and inhibition, regulators of inflammasome-dependent inflammation, and caspase activation. We recently got the opportunity to speak with Kate about gender equality in science, technology, engineering, and mathematics (STEM). We covered steps her institute is taking to improve gender equality in the workplace, advice for female early career researchers (ECRs), and how something as simple as a robot vacuum cleaner can make a huge difference to a person’s life.
COOMET.PR-S11 comparison of COLOUR REFLECTED. Final report
Authors: Huriev Mykola , Hovorova Ekaterina , Shirokov Stanislav , Ivashin Eugeniy , Tarasova Olga , Leecharoen Rojana , Meric Seval , Ruoduan Sun , Górnik Sylwia , Muminbekov Bekzod , Najmutdinov Kamoliddin , Rustamov Jamol
Published: February 2023

Main text

This report describes performing the international supplementary comparisons of the values ​​of colour coordinates and L *, a *, b * of reflecting surfaces transmitted by means of measurement standards - transfer standards from the participants of comparisons to the coordinating laboratory.

These comparisons were carried out within the framework of the regional metrological organization (RMO) "Euro-Asian Cooperation of National Metrological Institutions" (COOMET) in accordance with the COOMET 743 / UA / 18 Project.

The National Scientific Center "Institute of Metrology" (NSC "IM", Ukraine) acts as the coordinating laboratory for these comparisons.

Supplementary comparisons are aimed at determining the degree of equivalence (DoE) for the National Photometric Laboratories participating in these comparisons. The DoE shows the deviation of the color coordinates and L *, a *, b * values ​​of the reflecting surfaces obtained by the Participant from the Reference Values (RV) ​​obtained between the National Photometric Laboratories participating in these comparisons.

The comparisons will support the following CMCs from the classification of services in photometry and radiometry: color, reflection, Y, x, y,; color, reflection L *, a *, b *.

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

The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Achieving 1.2 fm/Hz1/2 Displacement Sensitivity with Laser Interferometry in Two-Dimensional Nanomechanical Resonators: Pathways towards Quantum-Noise-Limited Measurement at Room Temperature
Authors: Zhu Jiankai , Wang Luming , Wu Jiaqi , Liang Yachun , Xiao Fei , Xu Bo , Zhang Zejuan , Fan Xiulian , Zhou Yu , Xia Juan , Wang Zenghui
Published: February 2023

Laser interferometry is an important technique for ultrasensitive detection of motion and displacement. We push the limit of laser interferometry through noise optimization and device engineering. The contribution of noises other than shot noise is reduced from 92.6% to 62.4%, demonstrating the possibility towards shot-noise-limited measurement. Using noise thermometry, we quantify the laser heating effect and determine the range of laser power values for room-temperature measurements. With detailed analysis and optimization of signal transduction, we achieve 1.2 fm/Hz1/2 displacement measurement sensitivity at room temperature in two-dimensional (2D) CaNb2O6 nanomechanical resonators, the best value reported to date among all resonators based on 2D materials. Our work demonstrates a possible pathway towards quantum-noise-limited measurement at room temperature.
Optical Stern–Gerlach effect via a single traveling-wave light
Authors: Cui Haihu , Lai Wenxi
Published: February 2023

In this paper, we propose a simplified model of the optical Stern–Gerlach effect based on coherent coupling between the clock transition of alkaline-earth single atoms and a traveling-wave light. It is demonstrated that spin–orbit coupling-induced chiral motion in atom deflection appears under strong atom–light interaction. The strong optical driving removes the perturbation from the Doppler effect and back-action effect to access the coherent system. In this process, the superposition of distant matter waves connected to the arbitrary distribution of the atom internal state could be predicted, which is important for the realization of atom interferometry and quantum-state operation. The influence of atom relaxation and atom–atom interactions is discussed. The basic conditions for the experimental design are given at the end of this work.
The role of defects in the persistent photoconductivity of BaSnO3 thin films
Authors: Figueroa C , Villafuerte M , Straube B , Ferreyra J , Navarro C , Runco Leal V , Bridoux G
Published: February 2023

Time-dependent photoconductivity (PC) and PC spectra have been studied in oxygen deficient BaSnO3 thin films grown on different substrates. X-ray spectroscopy measurements show that the films have epitaxially grown on MgO and SrTiO3 substrates. While on MgO the films are nearly unstrained, on SrTiO3 the resulting film is compressive strained in the plane. Electrical conductivity in dark is increased in one order of magnitude for the films on SrTiO3 in comparison to the one on MgO. This leads to an increase of PC in the latter film in at least one order of magnitude. PC spectra show a direct gap with a value of

E

G

=
3.9

eV for the film grown on MgO while on SrTiO3

E

G

=
3.36

eV. For both type of films, time-dependent PC curves show a persistent behavior after illumination is removed. These curves have been fitted employing an analytical procedure based on the frame of PC as a transmission phenomenon showing the relevant role of donor and acceptor defects as carrier traps and as a source of carriers. This model also suggests that in the BaSnO3 film on SrTiO3 more defects are created probably due to strain. This latter effect can also explain the different transition values obtained for both type of films.
Dynamic data reconciliation to enhance the performance of model free adaptive control
Authors: Xia Tao , Zhang Zhengjiang , Hong Zhihui , Huang Shipei
Published: February 2023

As a novel data-driven control method, model-free adaptive control (MFAC) has a high requirement for the accuracy of the feedback signal. However, the sensor used to obtain the output inevitably contains measurement noise due to its own error or external interference, which may lead to an adverse effect on the control performance. The dynamic data reconciliation (DDR) is proposed and combined with MFAC to improve the control performance in this paper, which uses predicted output and measured data to suppress measurement noise considering Gaussian and non-Gaussian distributed measurement noise. The effectiveness of the DDR combined with MFAC (DDR-MFAC) is illustrated in the single-input single-output and multiple-input multiple-output systems with Gaussian and non-Gaussian distributed measurement noise. DDR-MFAC is also successfully applied to DC–AC converter, which improves its conversion precision.
Recent advances in MOF-bio-interface: a review
Authors: Li Yingfeng , Wang Ru , Liu Xue , Li Ke , Xu Qing
Published: February 2023

Metal-organic frameworks (MOFs), as a class of promising material with adjustable function and controllable structure, have been widely used in the food industry, chemical industry, biological medicine, and sensors. Biomacromolecules and living systems play a critical role in the world. However, the insufficiency in stability, recyclability, and efficiency, significantly impedes their further utilization in slightly harsh conditions. MOF-bio-interface engineering effectively address the above-mentioned shortages of biomacromolecules and living systems, and thereby attracting considerable attentions. Herein, we systematically review the achievements in the area of MOF-bio-interface. In particular, we summarize the interface between MOFs and proteins (enzymes and non-enzymatic proteins), polysaccharides, DNA, cells, microbes, and viruses. Meanwhile, we discuss the limitations of this approach and propose future research directions. We expect that this review could provide new insights and inspire new research efforts towards life science and material science.
A novel CVD graphene-based synaptic transistors with ionic liquid gate
Authors: Feng Xin , Qiao Lei , Huang Jingjing , Ning Jing , Wang Dong , Zhang Jincheng , Hao Yue
Published: February 2023

The synaptic devices based on various electronic materials have been widely investigated to realize functions of artificial information processing with low power consumption. In this work, a novel CVD graphene field-effect transistor is fabricated with ionic liquid gate to study the synaptic behaviors based on the electrical-double-layer mechanism. It is found that the excitative current is enhanced with the pulse width, voltage amplitude and frequency. With different situations of the applied pulse voltage, the inhibitory and excitatory behaviors are successfully simulated, at the same time the short-term memory is also realized. The corresponding ions migration and charge density variation are analyzed in the different time segments. This work provides the guidance for the design of artificial synaptic electronics with ionic liquid gate for low-power computing application.
Electron-impact state-to-state cross sections and rate coefficients for X(ν)→B(ν′) excitation of LiH molecule
Authors: Celiberto R , Laricchiuta A
Published: February 2023

Electron-impact cross sections for thev→v′transitions between the vibrational levels ofX1Σ+and the excitedB1Πelectronic states of LiH molecule, are calculated from threshold to 1000 eV by using thethreshold-modified Mott–Massey approximation. Cross sections for the dissociative process, occurring through the excitation to the continuum spectrum of the vibrational levels of theBstate, are also obtained. Maxwellian rate coefficients for the correspondingbound−to−boundandbound−to−continuumtransitions are presented in the temperature range of 0.1–10 000 eV. Finally, scaling relationships for both thev−v′cross section and rate coefficients are derived in order to represent the calculated quantities in a compact analytic form.
Design and analysis of a d15 mode piezoelectric energy generator using friction-induced vibration
Authors: Xiao Yu , Karnaoukh Sviatoslaw , Wu Nan
Published: February 2023

Research works have been conducted on transverse and longitudinal mode piezoelectric energy generation to collect energy from ambient vibrations. However, the inconsistency with the frequency of the energy source and low output power density remain problems for high energy output. In this work, we propose a shear mode piezoelectric energy generator, which utilizes the friction-induced vibration (FIV) and high shear mode piezoelectric coefficient to improve the energy output. A piezoelectric coupled FIV mathematical model is developed to accurately calculate the dynamic vibration response and voltage output. The dynamic voltage response is validated by experiment, and it proves the possibility of continuous friction-induced high-frequency vibration. The energy generation process is evaluated by transient charging simulation of a storage capacitor through an iteration process, which was experimentally validated in the literature. Parameter studies have been conducted to investigate the influences of the piezoelectric patch dimensional parameters, vibration system parameters, friction model parameters, methods of electrical connections, and different piezoelectric materials on the energy generation performance to provide guidance for better design. Under ideal experiment conditions with proper parameters, a volume of

6.25
×

10

−
8

m3 PZT4 piezoelectric material indicates root mean square (RMS) charging power density of

5.38
×

10
3

Wm−3 and

4.70
×

10
3

Wm−3 with electrically in parallel and electrically in series, respectively. While using the same amount of material and structural setup, the single crystal PMN-PT piezoelectric material shows RMS charging power density of

2.72
×

10
4

Wm−3 and

2.58
×

10
4

Wm−3 with electrically in parallel and electrically in series, correspondingly. These promising results demonstrate that close to W-level RMS charging power output may be realized by structure optimization of energy generator design and incorporating multiple generators together for operation. Possible incorporation into vehicle braking systems can be considered to utilize the wasted friction energy, and it may offer an energy supply for low-power wireless devices.
Effective pressure sensor using the parity-time symmetric photonic crystal
Authors: Zaky Zaky A , Al-Dossari M , Sharma Arvind , Aly Arafa H
Published: February 2023

Monitoring the variations in pressure, distribution, and the magnitude of the emitted gases at the ground surface is very important in different applications. Because of the parity-time symmetric mechanism, a novel one-dimensional photonic crystal as a pressure sensor is proposed. The transmittance spectra are calculated and analyzed using the transfer matrix method. The parity-time symmetric property amplifies the transmittance of the defect mode and gives an additional hand to enhance the magnification and performance of the sensor. The optimum conditions are the normal angle of incidence, defect layer thickness of 1400 nm, the porosity of the porous silicon layer of 80%, and macroscopic Lorentz oscillation intensity of 5 × 10-4. The results show that the position and amplitude sensitivities are 4.9 nm GPa−1 and 1844%/GPa. That means in such sensors, by altering pressure, the desired value of magnified transmittance and sensitivity can be achieved as required according to the optical communication devices. Therefore, the proposed device performs better with high precision and accuracy. Consequently, it is much more helpful in optical communication and optoelectronic devices.
Peridynamic modeling of damage and non-shock ignition behavior of confined polymer bonded explosives under impact loading
Authors: Deng Xiaoliang , Zhao Jibo , Huang Yafei
Published: February 2023

A mechanical-thermal-chemical coupled peridynamic (PD) modeling for analyzing the damage and non-shock ignition behavior of polymer bonded explosives (PBXs) subject to impact loading has been presented. The friction and heat conduction and Arrenhenius law are embedded into the PD theory, ensuring that the simulation model is capable of capturing major features of dynamic damage response of PBX. A PD material model considering plasticity and the asymmetric behaviors of PBX under tensile and compressive loadings is proposed in this study. For a ring-shaped PBX 9501 sample confined by the steel structures, the simulation results indicate that the PBX 9501 in the regions towards the impact face and support face suffers from the serious damage. Meanwhile, the corresponding average temperatures in these two regions are also higher than their counterparts in other regions due to the more intense interaction between PBX 9501 and the steel confinement structures. The ignition time decreases with the increasing impact velocity within the range of 40-120 m/s. The internal steel shell response is analyzed according to its velocity history within a representative box. It is found that the deformation process of internal steel shell is closely related to the complicated flow behaviors of PBX 9501.
RMF accessibility percolation on oriented graphs
Authors: Duque Frank , Ramirez-Gomez Daniel , Roldán-Correa Alejandro , Valencia Leon A
Published: February 2023

Accessibility percolation is a new type of percolation problem inspired by evolutionary biology: a random number, called its fitness, is assigned to each vertex of a graph, then a path in the graph is accessible if fitnesses are strictly increasing through it. In the rough Mount Fuji (RMF) model, the fitness function is defined on the graph as

ω
(
v
)
=
η
(
v
)
+
θ
⋅
d
(
v
)

, where θ is a positive number called the drift, d is the distance to the source of the graph and

η
(
v
)

are i.i.d. random variables. In this paper, we determine values of θ for having RMF accessibility percolation on the hypercube and the two-dimensional lattices

L

2

and

L

a
l
t

2

.
Quantum chaos and circuit parameter optimization
Authors: Kim Joonho , Oz Yaron , Rosa Dario
Published: February 2023

We consider quantum chaos diagnostics of the variational circuit states at random parameters and explore their connection to the circuit expressibility and optimizability. By measuring the operator spreading coefficient and the eigenvalue spectrum of the modular Hamiltonian of the reduced density matrix, we identify the emergence of universal random matrix ensembles in high-depth circuit states. The diagnostics that use the eigenvalue spectrum, e.g. operator spreading and entanglement entropy, turn out to be more accurate measures of the variational quantum algorithm optimization efficiency than those that use the level spacing distribution of the entanglement spectrum, such as r-statistics or spectral form factors.
Selective isolation of actinomycetes for inhibition activity against methicillin-resistant Staphylococcus aureus SK1
Authors: Sangkanu S , Puangsiri W , Sukhoom A
Published: February 2023

205 isolates of actinomycetes bacteria were isolated from soil samples collected from Satun province, Thailand. To have more chances to get diverse groups of actinomycetes bacteria, soil samples were treated using three different methods before inoculated on two selective media, humic acid-vitamin agar and coal vitamin agar. After two months of incubation at 30°C, all typically characteristic colonies of actinomycetes were picked and purified then tested for inhibition activity against a virulent pathogen, methicillin-resistant Staphylococcus aureus SK1 (MRSA SK 1) using double-layer agar plate method. There were 49 isolates (23.90%) showed inhibition zone against MRSA SK 1.
The Effects of Hydroxyapatite Nanoparticles on the Growth and Yield of Ginger (Zingiber officinale Roscoe) from Seedling to Tillering Stage
Authors: Chong W X , Kiew W Y , Low Y C , Lim T H , Tan H Y
Published: February 2023

Ginger (Zingiber officinale Roscoe) is one of the economically important crops in the domestic and global markets due to its versatile properties as a spice, flavoring agent and traditional medicine. Conventional ginger cultivation required a longer time frame to harvest and for soil restoration, which limited the productivity of ginger. Hydroponic systems represent a valuable solution for the problem of land availability with the benefits of shortened time frame, increased production yield and thereby increase the productivity of ginger farming. Besides that, many synthetic fertilizers have low nutrient use efficiency (NUE). Nanofertilizers with the characteristic of delivering nutrients in a controlled manner showed the potential to overcome this problem. The study aims to determine the effects of hydroxyapatite nanoparticles (HANP) on the growth and yield of ginger. In this study, hydroxyapatite nanoparticles were synthesized and characterized. Experiments were conducted to study the effect of different concentrations of hydroxyapatite nanoparticles on the growth, yield, chlorophyll contents and photosynthetic rate of hydroponically cultivated ginger. Cocopeat was selected as the planting medium and the Hoagland solution with modified formula was used for regular fertigation. The results showed that the increment (P<0.05) in number of leaves and chlorophyll content in HANP-treated plants (200 ppm HANP) from week 9 to week 13 and the higher percentage increment in photosynthetic rate from week 11 to week 13 (20-54%) in HANP-treated plants (200-1000 ppm) as compared to the control (10%). This showed the potential use of the HANP treatments for the next developmental stage of ginger.
Development of the lignin extraction method from para rubber wood sawdust with choline chloride-lactic acid deep eutectic solvent
Authors: Phinitphutchaphong J , Yodsri K , Oncharoen N , Srijan K , Wudtipan J , Kaewsara S , Puttarak P , Watcharin W , Chuenchom L
Published: February 2023

This work investigated the extraction of lignin from para rubber wood sawdust by deep eutectic solvent extraction (DES) using choline chloride-lactic acid (ChCl-LA). The DES extraction was operated using ChCl/LA with molar ratio of 1:10, and the lignin was extracted with good yields. To determine the optimal conditions for lignin extraction by this technique, various factors were studied, including extraction temperature (90-150 °C), extraction time (6-24 h), the amount of water required for lignin precipitation (150-300 mL), and precipitation time (24-48 h). The optimized conditions were achieved at 150 °C, 24 h, 300 mL of DI water and 48 h of precipitation time, and the highest extracted lignin content was 17.54%. Moreover, excessive water in the extracted solution can be recovered with evaporation, and it was discovered that similar extracted lignin content could be obtained (16.85%) by only using 150 mL of DI water during lignin precipitation but extending the precipitation time to 48 h. This study provides a simple, inexpensive, and environmentally friendly lignin extraction technique.
Topological phenomena at the oxide interfaces
Authors: Ravindran Kavya , Dey Jayjit Kumar , Keshri Aryan , Roul Basanta , Krupanidhi Saluru Baba , Das Sujit
Published: February 2023

Topological phenomena at the oxide interfaces attract the scientific community for the fertile ground of exotic physical properties and highly favorable applications in the area of high-density low-energy nonvolatile memory and spintronic devices. Synthesis of atomically controlled ultrathin high-quality films with superior interfaces and their characterization by high resolution experimental set up along with high output theoretical calculations matching with the experimental results make this field possible to explain some of the promising quantum phenomena and exotic phases. In this review, we highlight some of the interesting interface aspects in ferroic thin films and heterostructures including the topological Hall effect in magnetic skyrmions, strain dependent interlayer magnetic interactions, interlayer coupling mediated electron conduction, switching of noncollinear spin texture etc. Finally, a brief overview followed by the relevant aspects and future direction for understanding, improving, and optimizing the topological phenomena for next generation applications are discussed.
Trajectories of self-reported hearing and their associations with cognition: evidence from the United Kingdom and United States of America
Authors: Matthews Katey , Dawes Piers , Elliot Rebecca , Pendleton Neil , Tampubolon Gindo , Maharani Asri
Published: February 2023

Objective

This study aimed to investigate the relationships between trajectories of change in self-reported hearing over eight years with subsequent effects on cognition, measured using episodic memory.

Methods

Data were drawn from 5 waves (2008–2016) of the English Longitudinal Study of England (ELSA) and the Health and Retirement Study (HRS), involving 4,875 individuals aged 50+ at the baseline in ELSA and 6,365 in HRS. The latent growth curve modelling was used to identify trajectories of hearing over eight years, and linear regression models were performed to investigate the relationship between hearing trajectory memberships and episodic memory scores, controlling for confounding factors.

Results

Five trajectories of hearing (stable very good, stable fair, poor to fair/good, good to fair, and very good to good) were retained in each study. Individuals whose hearing remains suboptimal and those whose hearing deteriorates within suboptimal levels throughout eight years have significantly poorer episodic memory scores at follow-up than those with stable very good hearing. Conversely, individuals whose hearing declines but is within an optimal category at baseline do not see significantly poorer episodic memory scores than those with consistently optimal hearing. There was no significant relationship between individuals whose hearing improved from suboptimal baseline levels to optimal by follow-up and memory in ELSA. However, analysis using HRS data shows a significant improvement for this trajectory group (−1.260, P < 0.001).

Conclusions

Either stable fair or deterioration in hearing is associated with worse cognitive function, both stable good or improving hearing is associated with better cognitive function specifically episodic memory.
Making a greener planet: nature documentaries promote plant awareness
Authors: Kacprzyk Joanna , Clune Stephanie , Clark Clare , Kane Adam
Published: February 2023

Background and Aims

Plants underpin life on Earth and are essential to human existence. Alarmingly, almost 40% of plant species are under threat of extinction, with plants that are not directly useful to humans being particularly vulnerable. Plant diversity and its untapped resources require urgent protection to safeguard our future, but conservation initiatives are biased towards mammals and birds. Plant awareness disparity, formerly known as plant blindness, describes our tendency to ignore plant life and has been suggested to play a crucial role in the bias against funding and support for plant conservation programmes. Previous studies indicate that nature documentaries can generate shifts in audience awareness of animal species by providing vicarious connections to nature. Here, we investigated whether the plant-focused popular BBC show Green Planet had a similar effect for plants and stimulated audience engagement for information after the broadcast.

Methods

Online searches for further information were considered a form of engagement for evaluation of the interest of the audience in plants portrayed in Green Planet episodes. The big data activities (Google search engine and Wikipedia pageviews trends) related to the plants mentioned in Green Planet episodes were examined over the period covering the broadcast of the show in UK.

Key Results

Analyses indicate that Green Planet generated increased awareness and stimulated audience engagement for further information about plants featured in the show, with audience reaction driven by the screen time.

Conclusions

Natural history films can promote plant awareness, and culturomic tools can be used to assess their impact on the general public, potentially also to inform plant conservation strategies. These are promising findings as we strive to increase public awareness of the value of plant life.
Relative growth rate (RGR) and other confounded variables: mathematical problems and biological solutions
Authors: Lamont Byron B , Williams Matthew R , He Tianhua
Published: February 2023

Background

Relative growth rate (RGR) has a long history of use in biology. In its logged form, RGR = ln[(M + ΔM)/M], where M is size of the organism at the commencement of the study, and ΔM is new growth over time interval Δt. It illustrates the general problem of comparing non-independent (confounded) variables, e.g. (X + Y) vs. X. Thus, RGR depends on what starting M(X) is used even within the same growth phase. Equally, RGR lacks independence from its derived components, net assimilation rate (NAR) and leaf mass ratio (LMR), as RGR = NAR × LMR, so that they cannot legitimately be compared by standard regression or correlation analysis.

Findings

The mathematical properties of RGR exemplify the general problem of ‘spurious’ correlations that compare expressions derived from various combinations of the same component terms X and Y. This is particularly acute when X >> Y, the variance of X or Y is large, or there is little range overlap of X and Y values among datasets being compared. Relationships (direction, curvilinearity) between such confounded variables are essentially predetermined and so should not be reported as if they are a finding of the study. Standardizing by M rather than time does not solve the problem. We propose the inherent growth rate (IGR), lnΔM/lnM, as a simple, robust alternative to RGR that is independent of M within the same growth phase.

Conclusions

Although the preferred alternative is to avoid the practice altogether, we discuss cases where comparing expressions with components in common may still have utility. These may provide insights if (1) the regression slope between pairs yields a new variable of biological interest, (2) the statistical significance of the relationship remains supported using suitable methods, such as our specially devised randomization test, or (3) multiple datasets are compared and found to be statistically different. Distinguishing true biological relationships from spurious ones, which arise from comparing non-independent expressions, is essential when dealing with derived variables associated with plant growth analyses.
LDmat: efficiently queryable compression of linkage disequilibrium matrices
Authors: Weiner Rockwell J , Lakhani Chirag , Knowles David A , Gürsoy Gamze
Published: February 2023

Motivation

Linkage disequilibrium (LD) matrices derived from large populations are widely used in population genetics in fine-mapping, LD score regression, and linear mixed models for Genome-wide Association Studies (GWAS). However, these matrices can reach large sizes when they are derived from millions of individuals; hence, moving, sharing and extracting granular information from this large amount of data can be cumbersome.

Results

We sought to address the need for compressing and easily querying large LD matrices by developing LDmat. LDmat is a standalone tool to compress large LD matrices in an HDF5 file format and query these compressed matrices. It can extract submatrices corresponding to a sub-region of the genome, a list of select loci, and loci within a minor allele frequency range. LDmat can also rebuild the original file formats from the compressed files.

Availability and implementation

LDmat is implemented in python, and can be installed on Unix systems with the command ‘pip install ldmat’. It can also be accessed through https://github.com/G2Lab/ldmat and https://pypi.org/project/ldmat/.

Supplementary information

Supplementary data are available at Bioinformatics online.
Local synchronicity in dopamine-rich caudate nucleus influences Huntington’s disease motor phenotype
Authors: Kasper Jan , Eickhoff Simon B , Caspers Svenja , Peter Jessica , Dogan Imis , Wolf Robert Christian , Reetz Kathrin , Dukart Juergen , Orth Michael
Published: February 2023

Structural grey and white matter changes precede the manifestation of clinical signs of Huntington’s disease by many years. Conversion to clinically manifest disease therefore likely reflects not merely atrophy but a more widespread breakdown of brain function. Here, we investigated the structure–function relationship close to and after clinical onset, in important regional brain hubs, particularly caudate nucleus and putamen, which are central to maintaining normal motor behaviour. In two independent cohorts of patients with premanifest Huntington’s disease close to onset and very early manifest Huntington’s disease (total n = 84; n = 88 matched controls), we used structural and resting state functional MRI.

We show that measures of functional activity and local synchronicity within cortical and subcortical regions remain normal in the premanifest Huntington’s disease phase despite clear evidence of brain atrophy. In manifest Huntington’s disease, homeostasis of synchronicity was disrupted in subcortical hub regions such as caudate nucleus and putamen, but also in cortical hub regions, for instance the parietal lobe. Cross-modal spatial correlations of functional MRI data with receptor/neurotransmitter distribution maps showed that Huntington’s disease-specific alterations co-localize with dopamine receptors D1 and D2, as well as dopamine and serotonin transporters. Caudate nucleus synchronicity significantly improved models predicting the severity of the motor phenotype or predicting the classification into premanifest Huntington’s disease or motor manifest Huntington’s disease.

Our data suggest that the functional integrity of the dopamine receptor-rich caudate nucleus is key to maintaining network function. The loss of caudate nucleus functional integrity affects network function to a degree that causes a clinical phenotype. These insights into what happens in Huntington’s disease could serve as a model for what might be a more general relationship between brain structure and function in neurodegenerative diseases in which other brain regions are vulnerable.
Features of BAFF and APRIL receptors on circulating B cells in antineutrophil cytoplasmic antibody-associated vasculitis
Authors: Shimojima Yasuhiro , Kishida Dai , Ichikawa Takanori , Takamatsu Ryota , Nomura Shun , Sekijima Yoshiki
Published: February 2023

To investigate the features of circulating B cells, their expressing receptors, serum levels of B-cell activation factor of the TNF family (BAFF), and a proliferation-inducing ligand (APRIL) in antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Blood samples from 24 patients with active AAV (a-AAV), 13 with inactive AAV (i-AAV), and 19 healthy controls (HC) were included in this study. The proportion of B cells and their expressing BAFF receptor (BAFF-R), transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), and B-cell maturation antigen were analyzed via flow cytometry. Serum levels of BAFF, APRIL, and interleukin (IL)-4, IL-6, IL-10, and IL-13 were also evaluated using an enzyme-linked immunosorbent assay. The proportion of plasmablasts (PB)/plasma cells (PC) and serum levels of BAFF, APRIL, IL-4, and IL-6 were significantly higher in a-AAV than in HC. Higher serum levels of BAFF, APRIL, and IL-4 were observed in i-AAV than in HC. Lower expression of BAFF-R on memory B cells and higher expression of TACI on CD19+ cells, immature B cells, and PB/PC were demonstrated in a-AAV and i-AAV than in HC. The population of memory B cells was positively associated with serum APRIL levels and BAFF-R expression in a-AAV. In conclusion, decreased expression of BAFF-R on memory B cells and increased expression of TACI on CD19+ cells, immature B cells, and PB/PC, as well as increased serum levels of BAFF and APRIL, were sustained even in the remission phase of AAV. Persistent aberrant signaling of BAFF/APRIL may contribute to disease relapse.
Physician Financial Incentives for Use of Outpatient Intravenous Antimicrobial Therapy: An Interrupted Time Series Analysis
Authors: Staples John A , Ho Meghan , Ferris Dwight , Liu Guiping , Brubacher Jeffrey R , Khan Mayesha , Daly-Grafstein Daniel , Tran Karen C , Sutherland Jason M
Published: February 2023

Background

In 2011, policymakers in British Columbia introduced a fee-for-service payment to incentivize infectious diseases physicians to supervise outpatient parenteral antimicrobial therapy (OPAT). Whether this policy increased use of OPAT remains uncertain.

Methods

We conducted a retrospective cohort study using population-based administrative data over a 14-year period (2004–2018). We focused on infections that required intravenous antimicrobials for ≥10 days (eg, osteomyelitis, joint infection, endocarditis) and used the monthly proportion of index hospitalizations with a length of stay shorter than the guideline-recommended “usual duration of intravenous antimicrobials” (LOS < UDIVA) as a surrogate for population-level OPAT use. We used interrupted time series analysis to determine whether policy introduction increased the proportion of hospitalizations with LOS < UDIVA.

Results

We identified 18 513 eligible hospitalizations. In the pre-policy period, 82.3% of hospitalizations exhibited LOS < UDIVA. Introduction of the incentive was not associated with a change in the proportion of hospitalizations with LOS < UDIVA, suggesting that the policy intervention did not increase OPAT use (step change, −0.06%; 95% confidence interval [CI], −2.69% to 2.58%; P = .97 and slope change, −0.001% per month; 95% CI, −.056% to .055%; P = .98).

Conclusions

The introduction of a financial incentive for physicians did not appear to increase OPAT use. Policymakers should consider modifying the incentive design or addressing organizational barriers to expanded OPAT use.
Against Normative Damages
Authors: Descheemaeker Eric
Published: February 2023

This paper examines an idea which has made some headway into legal scholarship and case law, namely, that the violation of a right ought to sound in substantial (compensatory) damages in and by itself, independently of any factual loss caused to the claimant. This doctrine of ‘normative damages’ was rejected, rightly, by the High Court of Australia in the wrongful imprisonment case of Lewis v. ACT in 2020. However, although the rejection was unanimous, its clarity was undermined by the fact that the issue of normative damages was intertwined with considerations of causal counterfactuals and the definition of false imprisonment. This article considers the doctrine in a broader perspective, examining where it has come from and arguing that normative damages are wrong as a matter of principle: not only do they contradict foundational principles of the Anglo-Commonwealth law of damages, they effectively amount to considering the same injury twice.
Innate immune memory in cardiometabolic disease
Authors: Bahrar Harsh , Bekkering Siroon , Stienstra Rinke , Netea Mihai G , Riksen Niels P
Published: February 2023

Low-grade systemic inflammation is a key pathophysiological component of atherosclerotic cardiovascular disease (CVD), and long-term activation of myeloid cells is thought to be crucial for these effects. Obesity and associated metabolic complications including hyperglycaemia and dyslipoproteinaemia can induce long-lasting inflammatory reprogramming of the innate immune cells and their bone marrow progenitors, which in turn contributes to atherosclerosis. In this review, we discuss the mechanisms through which innate immune cells undergo long-term changes in their functional, epigenetic, and metabolic characteristics upon even short-term exposure to endogenous ligands, a process also termed ‘trained immunity’. Inappropriate induction of trained immunity leads to the development of long-lasting hyperinflammatory and proatherogenic changes in monocytes and macrophages, an important factor in the development of atherosclerosis and CVDs. Knowledge of the specific immune cells and the distinct intracellular molecular pathways involved in the induction of trained immunity will reveal novel pharmacological targets that could be used to prevent or treat CVDs in the future.
Kinematic parameters related to functional capacity, fatigue, and breathlessness during the 6-min walk test in older adults with heart failure with preserved ejection fraction
Authors: Fuentes-Abolafio Iván José , Trinidad-Fernández Manuel , Ricci Michele , Roldán-Jiménez Cristina , Gómez-Huelgas Ricardo , Arjona-Caballero José María , Escriche-Escuder Adrián , Bernal-López María Rosa , Pérez-Belmonte Luis Miguel , Cuesta-Vargas Antonio Ignacio
Published: February 2023

Aims

This paper aims to assess kinematic parameters related to functional capacity, fatigue, and breathlessness during the 6-min walk test (6MWT) in patients with heart failure with preserved ejection fraction (HFpEF).

Methods and results

A cross-sectional study was conducted in which adults 70 years or older with HFpEF were voluntarily recruited between April 2019 and March 2020. An inertial sensor was placed at the L3–L4 level and another on the sternum to assess kinematic parameters. The 6MWT was divided into two 3-min phases. Leg fatigue and breathlessness, assessed by the Borg scale, the heart rate (HR), and the oxygen saturation (SpO2), were measured at the beginning and the end of the 6MWT. The difference in kinematic parameters between the 6MWT two 3-min phases was also calculated. Bivariate Pearson correlations and subsequent multivariate linear regression analysis were performed. Seventy older adults with HFpEF (mean = 80.74 years old) were included. Kinematic parameters explained 81.00% of the functional capacity, 45.50% of the leg fatigue and 66.10% of the breathlessness variance. Moreover, kinematic parameters could explain 30.90% of the SpO2 variance at the end of the 6MWT. Kinematic parameters also explained 33.10% of the SpO2 difference between the beginning and end of 6MWT. Kinematic parameters explained neither the HR variance at the end of 6MWT nor the HR difference between the beginning and end.

Conclusion

Gait kinematics from L3-L4 and sternum explain a part of the variance in subjective outcomes, assessed by the Borg scale, and objective outcomes such as functional capacity and SpO2. The kinematic assessment allows clinicians to quantify fatigue and breathlessness through objective parameters related to the patient’s functional capacity.

Registration

ClinicalTrials.gov NCT03909919.
Coherent mapping of atrial tachycardias in patients with congenital heart disease
Authors: Klehs Sophia , Paech Christian , Bertagnolli Livio , Markel Franziska , Dähnert Ingo , Gebauer Roman
Published: February 2023

Aims

Coherent mapping (CM) uses a new algorithm to identify critical conduction isthmuses of atrial tachycardias (ATs). We analysed our experience of ablation of AT in patients with congenital heart disease (CHD) with this new technology.

Methods and results

All patients with CHD who had CM of AT using the high-density mapping PENTARAY™ catheter and three-dimensional electroanatomic mapping system Carto3 between June 2019 and June 2021 were included retrospectively (n = 27). As a control group, 27 patients with CHD and mapping of AT without CM between March 2016 and June 2019 were included. In total, 54 ablation procedures were performed in 42 patients [median age 35 (interquartile range, IQR 30–48) years] and 64 ATs were induced and mapped (thereof 50 AT intraatrial re-entrant tachycardia and 14 AT ectopic AT). The median procedure duration was 180 (120–214) min and median fluoroscopy time was 10 (5.2–14) min. Acute success was 100% (27/27) in the Coherence group and 74% (20/27) in the non-Coherence group (P = 0.01). During follow-up [median 26 (12–45) months], AT recurred in 28/54 patients, thereof 15 patients needed a re-ablation procedure. Log-rank test showed no difference in recurrence rate between the two groups (P = 0.29). Three minor complications occurred (5.5%).

Conclusion

Mapping of AT in patients with CHD using the PENTARAY™ mapping catheter and the CM algorithm led to excellent acute success. All ATs were possible to map and no complications related to the PENTARAY™ mapping catheter were observed. Thus, the use of the CM algorithm represents a promising tool in patients with CHD and complex AT.
Mapping-guided atrial lead placement determines optimal conduction across Bachmann’s bundle: a rationale for patient-tailored pacing therapy
Authors: van Schie Mathijs S , Ramdat Misier Nawin L , Knops Paul , Heida Annejet , Taverne Yannick J H J , de Groot Natasja M S
Published: February 2023

Aims

Conventional right atrial appendage (RAA) pacing is associated with increased atrial activation time resulting in higher incidences of atrial tachyarrhythmia. Optimal pacing sites ideally shorten inter-atrial conduction delay, thereby decreasing atrial excitation time. We therefore examined the impact of programmed electrical stimulation (PES) from the right atrium (RA) and left atrium (LA) on the electrophysiological properties of Bachmann’s bundle (BB).

Methods and results

High-resolution epicardial mapping of BB was performed during sinus rhythm (SR) and PES in 34 patients undergoing cardiac surgery. Programmed electrical stimulation was performed from the RAA, junction of the RA with inferior caval vein (LRA), and left atrial appendage (LAA). Pacing from either the RAA or LAA resulted in, respectively, right- and left-sided conduction across BB. However, during LRA pacing in most patients (n = 15), activation started in the centre of BB. The total activation time (TAT) of BB during RAA pacing [63 (55–78) ms] was similar to that of SR [61 (52–68) ms, P = 0.464], while it decreased during LRA [45 (39–62) ms, P = 0.003] and increased during LAA pacing [67 (61–75) ms, P = 0.009]. Reduction of both conduction disorders and TAT was most often achieved during LRA pacing (N = 13), especially in patients who already had a higher amount of conduction disorders during SR [9.8 (7.3–12.3) vs. 4.5 (3.5–6.6)%, P < 0.001].

Conclusion

Pacing from the LRA results in a remarkable decrease of TAT compared with pacing from the LAA or RAA. As the most optimal pacing site varies between patients, individualized positioning of the atrial pacing lead guided by mapping of BB may be one of the new frontiers for atrial pacing.