bluuebunny/crossref_metadata_2025 huggingface dataset:
Collective behavior and nongenetic inheritance allow bacterial populations to adapt to changing environments
Authors: Mattingly Henry H. , Emonet Thierry
Published: June 2022

Collective behaviors require coordination among a group of individuals. As a result, individuals that are too phenotypically different from the rest of the group can be left out, reducing heterogeneity, but increasing coordination. If individuals also reproduce, the offspring can have different phenotypes from their parent(s). This raises the question of how these two opposing processes—loss of diversity by collective behaviors and generation of it through growth and inheritance—dynamically shape the phenotypic composition of an isogenic population. We examine this question theoretically using collective migration of chemotactic bacteria as a model system, where cells of different swimming phenotypes are better suited to navigate in different environments. We find that the differential loss of phenotypes caused by collective migration is environment-dependent. With cell growth, this differential loss enables migrating populations to dynamically adapt their phenotype compositions to the environment, enhancing migration through multiple environments. Which phenotypes are produced upon cell division depends on the level of nongenetic inheritance, and higher inheritance leads to larger composition adaptation and faster migration at steady state. However, this comes at the cost of slower responses to new environments. Due to this trade-off, there is an optimal level of inheritance that maximizes migration speed through changing environments, which enables a diverse population to outperform a nondiverse one. Growing populations might generally leverage the selection-like effects provided by collective behaviors to dynamically shape their own phenotype compositions, without mutations.
Affinity of disordered protein complexes is modulated by entropy–energy reinforcement
Authors: Hazra Milan Kumar , Levy Yaakov
Published: June 2022

The association between two intrinsically disordered proteins (IDPs) may produce a fuzzy complex characterized by a high binding affinity, similar to that found in the ultrastable complexes formed between two well-structured proteins. Here, using coarse-grained simulations, we quantified the biophysical forces driving the formation of such fuzzy complexes. We found that the high-affinity complex formed between the highly and oppositely charged H1 and ProTα proteins is sensitive to electrostatic interactions. We investigated 52 variants of the complex by swapping charges between the two oppositely charged proteins to produce sequences whose negatively or positively charged residue content was more homogeneous or heterogenous (i.e., polyelectrolytic or polyampholytic, having higher or lower absolute net charges, respectively) than the wild type. We also changed the distributions of oppositely charged residues within each participating sequence to produce variants in which the charges were segregated or well mixed. Both types of changes significantly affect binding affinity in fuzzy complexes, which is governed by both enthalpy and entropy. The formation of H1–ProTa is supported by an increase in configurational entropy and by entropy due to counterion release. The latter can be twice as large as the former, illustrating the dominance of counterion entropy in modulating the binding thermodynamics. Complexes formed between proteins with greater absolute net charges are more stable, both enthalpically and entropically, indicating that enthalpy and entropy have a mutually reinforcing effect. The sensitivity of the thermodynamics of the complex to net charge and the charge pattern within each of the binding constituents may provide a means to achieve binding specificity between IDPs.
Time and skeptical opinion content erode the effects of science coverage on climate beliefs and attitudes
Authors: Nyhan Brendan , Porter Ethan , Wood Thomas J.
Published: June 2022

Although experiments show that exposure to factual information can increase factual accuracy, the public remains stubbornly misinformed about many issues. Why do misperceptions persist even when factual interventions generally succeed at increasing the accuracy of people’s beliefs? We seek to answer this question by testing the role of information exposure and decay effects in a four-wave panel experiment (n= 2,898 at wave 4) in which we randomize the media content that people in the United States see about climate change. Our results indicate that science coverage of climate change increases belief accuracy and support for government action immediately after exposure, including among Republicans and people who reject anthropogenic climate change. However, both effects decay over time and can be attenuated by exposure to skeptical opinion content (but not issue coverage featuring partisan conflict). These findings demonstrate that the increases in belief accuracy generated by science coverage are short lived and can be neutralized by skeptical opinion content.
Photosynthetic biohybrid coculture for tandem and tunable CO
2
and N
2
fixation
Authors: Cestellos-Blanco Stefano , Chan Rachel R. , Shen Yue-xiao , Kim Ji Min , Tacken Tom A. , Ledbetter Rhesa , Yu Sunmoon , Seefeldt Lance C. , Yang Peidong
Published: June 2022

Solar-driven bioelectrosynthesis represents a promising approach for converting abundant resources into value-added chemicals with renewable energy. Microorganisms powered by electrochemical reducing equivalents assimilate CO
2
, H
2
O, and N
2
building blocks. However, products from autotrophic whole-cell biocatalysts are limited. Furthermore, biocatalysts tasked with N
2
reduction are constrained by simultaneous energy-intensive autotrophy. To overcome these challenges, we designed a biohybrid coculture for tandem and tunable CO
2
and N
2
fixation to value-added products, allowing the different species to distribute bioconversion steps and reduce the individual metabolic burden. This consortium involves acetogen
Sporomusa ovata
, which reduces CO
2
to acetate, and diazotrophic
Rhodopseudomonas palustris
, which uses the acetate both to fuel N
2
fixation and for the generation of a biopolyester. We demonstrate that the coculture platform provides a robust ecosystem for continuous CO
2
and N
2
fixation, and its outputs are directed by substrate gas composition. Moreover, we show the ability to support the coculture on a high–surface area silicon nanowire cathodic platform. The biohybrid coculture achieved peak faradaic efficiencies of 100, 19.1, and 6.3% for acetate, nitrogen in biomass, and ammonia, respectively, while maintaining product tunability. Finally, we established full solar to chemical conversion driven by a photovoltaic device, resulting in solar to chemical efficiencies of 1.78, 0.51, and 0.08% for acetate, nitrogenous biomass, and ammonia, correspondingly. Ultimately, our work demonstrates the ability to employ and electrochemically manipulate bacterial communities on demand to expand the suite of CO
2
and N
2
bioelectrosynthesis products.
Immune checkpoint inhibitors unleash pathogenic immune responses against the microbiota
Authors: Hu Zishuo Ian , Link Verena M. , Lima-Junior Djalma S. , Delaleu Jérémie , Bouladoux Nicolas , Han Seong-Ji , Collins Nicholas , Belkaid Yasmine
Published: June 2022

Immune checkpoint inhibitors (ICIs) are essential components of the cancer therapeutic armamentarium. While ICIs have demonstrated remarkable clinical responses, they can be accompanied by immune-related adverse events (irAEs). These inflammatory side effects are of unclear etiology and impact virtually all organ systems, with the most common being sites colonized by the microbiota such as the skin and gastrointestinal tract. Here, we establish a mouse model of commensal bacteria–driven skin irAEs and demonstrate that immune checkpoint inhibition unleashes commensal-specific inflammatory T cell responses. These aberrant responses were dependent on production of IL-17 by commensal-specific T cells and induced pathology that recapitulated the cutaneous inflammation seen in patients treated with ICIs. Importantly, aberrant T cell responses unleashed by ICIs were sufficient to perpetuate inflammatory memory responses to the microbiota months following the cessation of treatment. Altogether, we have established a mouse model of skin irAEs and reveal that ICIs unleash aberrant immune responses against skin commensals, with long-lasting inflammatory consequences.
Photocontrolled crRNA activation enables robust CRISPR-Cas12a diagnostics
Authors: Hu Menglu , Qiu Zhiqiang , Bi Zirong , Tian Tian , Jiang Yongzhong , Zhou Xiaoming
Published: June 2022

CRISPR diagnostics based on nucleic acid amplification faces barriers to its commercial use, such as contamination risks and insufficient sensitivity. Here, we propose a robust solution involving optochemical control of CRISPR RNA (crRNA) activation in CRISPR detection. Based on this strategy, recombinase polymerase amplification (RPA) and CRISPR-Cas12a detection systems can be integrated into a completely closed test tube. crRNA can be designed to be temporarily inactivated so that RPA is not affected by Cas12a cleavage. After the RPA reaction is completed, the CRISPR-Cas12a detection system is activated under rapid light irradiation. This photocontrolled, fully closed CRISPR diagnostic system avoids contamination risks and exhibits a more than two orders of magnitude improvement in sensitivity compared with the conventional one-pot assay. This photocontrolled CRISPR method was applied to the clinical detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, achieving detection sensitivity and specificity comparable to those of PCR. Furthermore, a compact and automatic photocontrolled CRISPR detection device was constructed.
The interaction of ice and law in Arctic marine accessibility
Authors: Lynch Amanda H. , Norchi Charles H. , Li Xueke
Published: June 2022

Sea ice levies an impost on maritime navigability in the Arctic, but ice cover diminution due to anthropogenic climate change is generating expectations for improved accessibility in coming decades. Projections of sea ice cover retreating preferentially from the eastern Arctic suggest key provisions of international law of the sea will require revision. Specifically, protections against marine pollution in ice-covered seas enshrined in Article 234 of the United Nations Convention on the Law of the Sea have been used in recent decades to extend jurisdictional competence over the Northern Sea Route only loosely associated with environmental outcomes. Projections show that plausible open water routes through international waters may be accessible by midcentury under all but the most aggressive of emissions control scenarios. While inter- and intraannual variability places the economic viability of these routes in question for some time, the inevitability of a seasonally ice-free Arctic will be attended by a reduction of regulatory friction and a recalibration of associated legal frameworks.
VEGF is an essential retrograde trophic factor for motoneurons
Authors: Calvo Paula M. , Hernández Rosendo G. , de la Cruz Rosa R. , Pastor Angel M.
Published: June 2022

VEGF was initially discovered due to its angiogenic activity and therefore named “vascular endothelial growth factor.” However, its more recently discovered neurotrophic activity may be evolutionarily more ancient. Our previous work showed that all the changes produced by axotomy on the firing activity and synaptic inputs of abducens motoneurons were completely restored after VEGF administration. Therefore, we hypothesized that the lack of VEGF delivered by retrograde transport from the periphery should also affect the physiology of otherwise intact abducens motoneurons. For VEGF retrograde blockade, we chronically applied a neutralizing VEGF antibody to the lateral rectus muscle. Recordings of extracellular single-unit activity and eye movements were made in alert cats before and after the application of the neutralizing antibody. Our data revealed that intact, noninjured abducens motoneurons retrogradely deprived of VEGF exhibited noticeable changes in their firing pattern. There is a general decrease in firing rate and a significant reduction in eye position and eye velocity sensitivity (i.e., a decrease in the tonic and phasic components of their discharge, respectively). Moreover, by means of confocal immunocytochemistry, motoneurons under VEGF blockade showed a marked reduction in the density of afferent synaptic terminals contacting with their cell bodies. Altogether, the present findings demonstrate that the lack of retrogradely delivered VEGF renders abducens motoneurons into an axotomy-like state. This indicates that VEGF is an essential retrograde factor for motoneuronal synaptic drive and discharge activity.
Hybrid measurement of respiratory aerosol reveals a dominant coarse fraction resulting from speech that remains airborne for minutes
Authors: Shen Yang , Courtney Joseph M. , Anfinrud Philip , Bax Adriaan
Published: June 2022

Accurate measurements of the size and quantity of aerosols generated by various human activities in different environments are required for efficacious mitigation strategies and accurate modeling of respiratory disease transmission. Previous studies of speech droplets, using standard aerosol instrumentation, reported very few particles larger than 5 μm. This starkly contrasts with the abundance of such particles seen in both historical slide deposition measurements and more recent light scattering observations. We have reconciled this discrepancy by developing an alternative experimental approach that addresses complications arising from nucleated condensation. Measurements reveal that a large volume fraction of speech-generated aerosol has diameters in the 5- to 20-μm range, making them sufficiently small to remain airborne for minutes, not hours. This coarse aerosol is too large to penetrate the lower respiratory tract directly, and its relevance to disease transmission is consistent with the vast majority of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections initiating in the upper respiratory tract. Our measurements suggest that in the absence of symptoms such as coughing or sneezing, the importance of speech-generated aerosol in the transmission of respiratory diseases is far greater than generally recognized.
Functionally linked potassium channel activity in cerebral endothelial and smooth muscle cells is compromised in Alzheimer’s disease
Authors: Taylor Jade L. , Pritchard Harry A. T. , Walsh Katy R. , Strangward Patrick , White Claire , Hill-Eubanks David , Alakrawi Mariam , Hennig Grant W. , Allan Stuart M. , Nelson Mark T. , Greenstein Adam S.
Published: June 2022

The brain microcirculation is increasingly viewed as a potential target for disease-modifying drugs in the treatment of Alzheimer’s disease patients, reflecting a growing appreciation of evidence that cerebral blood flow is compromised in such patients. However, the pathogenic mechanisms in brain resistance arteries underlying blood flow defects have not yet been elucidated. Here we probed the roles of principal vasodilatory pathways in cerebral arteries using the APP23 mouse model of Alzheimer’s disease, in which amyloid precursor protein is increased approximately sevenfold, leading to neuritic plaques and cerebrovascular accumulation of amyloid-β similar to those in patients with Alzheimer’s disease. Pial arteries from APP23 mice (18 mo old) exhibited enhanced pressure-induced (myogenic) constriction because of a profound reduction in ryanodine receptor-mediated, local calcium-release events (“Ca2+sparks”) in arterial smooth muscle cells and a consequent decrease in the activity of large-conductance Ca2+-activated K+(BK) channels. The ability of the endothelial cell inward rectifier K+(Kir2.1) channel to cause dilation was also compromised. Acute application of amyloid-β 1-40 peptide to cerebral arteries from wild-type mice partially recapitulated the BK dysfunction seen in APP23 mice but had no effect on Kir2.1 function. If mirrored in human Alzheimer’s disease, these tandem defects in K+channel-mediated vasodilation could account for the clinical cerebrovascular presentation seen in patients: reduced blood flow and crippled functional hyperemia. These data direct future research toward approaches that reverse this dual vascular channel dysfunction, with the ultimate aim of restoring healthy cerebral blood flow and improving clinical outcomes.
Erratic velars in West-Coastal Bantu
Authors: Pacchiarotti Sara , Bostoen Koen
Published: June 2022

In this article, we present the first quantitative study of what we call multiple unconditioned reflexes (MUR) in Bantu, more specifically of Proto-Bantu velar stops *k and *g in the West-Coastal Bantu (WCB) branch of the Bantu language family. MUR, also known as “doubles reflexes” in Bantu studies, represent a situation where one and the same proto-sound has two or more reflexes in a given language which cannot be accounted for by phonological conditioning and/or lexical borrowing. This diachronic irregularity has been explained in Bantu historical linguistics, and Niger-Congo studies more broadly, by reconstructing either an additional series of consonants (phonemic merger) or a latent conditioning that went lost (phonemic split). We show that MUR should not be explained, but rather taken as an indicator of the same pervasive irregularity of sound change reported in other parts of the world that are highly multilingual and lack a neat overlap between distinct languages and communities. Along with widespread multilingualism, we assess lexical diffusion, substrate influence, and spread-over-spread events in Bantu language history as complementary explanations for the rise of MUR in WCB.
Palestinian kindergarten teachers in Israel and Arabic education policy
Authors: Kassem Abeer Shahbari , Amara Muhammad
Published: June 2022

This study aims to explore language education policy among Palestinian Arab kindergarten teachers in Israel, employing the framework of language policy proposed bySpolsky (2009), based on three major components: language practices, language ideologies, and language management. A mixed-method research approach consisting of both quantitative and qualitative methods of data collection is employed. A questionnaire was completed by a total of 509 kindergarten teachers. In addition, a semi-structured interview was carried out with 12 kindergarten teachers, selected from among those who answered the questionnaire, in order to gain a deeper understanding about Arabic language education policy. The data revealed that Palestinian Arab kindergarten teachers in Israel mostly use a mixture of Standard Arabic (StA) and Spoken Arabic (SpA) as the medium of instruction, using Hebrew or foreign words only sparingly. They express positive attitudes towards Arabic’s role as an important language in Israel. They also show positive attitudes about StA, believing that it is necessary to master it, yet facing difficulties while using it when speaking with the children. Regarding language management, they conduct activities that help develop StA skills, both for themselves and their students. Finally, there are significant interrelations between the kindergarten teachers’ background variables (religion, type of city they live in, seniority, education, and district) and language practice, ideology, and management. Based on these findings, it is important to construct a clearly-defined StA educational policy in Arab kindergartens.
Blood flow meets mitophagy
Authors: Akmeriç Emir Bora , Gerhardt Holger
Published: June 2022

Since its discovery as a mechanosensitive transcription factor in endothelial networks, Klf2’s varying expression levels under different blood flow patterns remained a mystery. In this study, Coon et al. (2022. J. Cell Biol.https://doi.org/10.1083/jcb.202109144) discover a connection between sustained laminar shear stress and mitochondrial flux that contributes to Klf2’s transcriptional dynamics.
Development of Time-of-Flight Polarized Neutron Imaging at the China Spallation Neutron Source
Authors: Salman Ahmed , Zhou Jianrong , Yang Jianqing , Zhang Junpei , Huang Chuyi , Ye Fan , Qin Zecong , Jiang Xingfen , Amir Syed Mohd , Kreuzpaintner Wolfgang , Sun Zhijia , Wang Tianhao , Tong Xin
Published: June 2022

A time-of-flight polarized neutron imaging setup was realized by integrating an in situ pumped polarized 3He spin filter and energy dispersive neutron camera on the neutron technique development beamline (BL-20) of the China Spallation Neutron Source (CSNS). Test experiments were performed with a solenoid with aluminum wire as a sample. These demonstrated that polarized radiography with a field of view in diameter 2.0 cm at different wavelengths can be obtained. The wavelength-dependent polarization was used to distinguish the neutron polarization behavior for different positions inside and outside the solenoid. The results of this work show the possibility of applying the technique at CSNS and marks a milestone for future polarized neutron imaging developments.
Emergence of Superconductivity on the Border of Antiferromagnetic Order in RbMn6Bi5 under High Pressure: A New Family of Mn-Based Superconductors
Authors: Yang Peng-Tao , Dong Qing-Xin , Shan Peng-Fei , Liu Zi-Yi , Sun Jian-Ping , Dun Zhi-Ling , Uwatoko Yoshiya , Chen Gen-Fu , Wang Bo-Sen , Cheng Jin-Guang
Published: June 2022

We report the discovery of superconductivity on the border of antiferromagnetic order in a quasi-one-dimensional material RbMn6Bi5 via measurements of resistivity and magnetic susceptibility under high pressures. Its phase diagram of temperature versus pressure resembles those of many magnetism-mediated superconducting systems. With increasing pressure, its antiferromagnetic ordering transition with T
N = 83 K at ambient pressure is first enhanced moderately and then suppressed completely at a critical pressure of P
c ≈ 13 GPa, around which bulk superconductivity emerges and exhibits a dome-like T
c(P) with a maximal

T
c

onset

≈
9.5

K at about 15 GPa. In addition, the superconducting state around P
c is characterized by a large upper critical field μ
0
H
c2(0) exceeding the Pauli paramagnetic limit, implying a possible unconventional paring mechanism. The present study, together with our recent work on KMn6Bi5 (the maximum

T
c

onset

≈
9.3

K), makes AMn6Bi5 (A = alkali metal) a new family of Mn-based superconductors with relatively high T
c.
Phase Diagram of the BCS–Hubbard Model in a Magnetic Field
Authors: Xu Dong-Hong , Yu Yi-Cong , Han Xing-Jie , Chen Xi , Wang Kang , Qin Ming-Pu , Liao Hai-Jun , Xiang Tao
Published: June 2022

We propose an extended BCS–Hubbard model and investigate its ground state phase diagram in an external magnetic field. By mapping the model onto a model of spinless fermions coupled with conserving Z
2 variables which are mimicked by pseudospins, the model is shown to be exactly solvable along the symmetric lines for an arbitrary on-site Hubbard interaction on the bipartite lattice. In the zero field limit, the ground states exhibit an antiferromagnetic order of pseudospins. In the large field limit, on the other hand, the pseudospins are fully polarized ordered. With the increase of the applied field, a first-order phase transition occurs between these kinds of phases when the on-site Coulomb interaction is less than a critical value U
c. Above this critical U
c, a novel intermediate phase emerges between the fully polarized and antiferromagnetic phases. The ground states in this phase are macroscopically degenerate, like in a spin ice, and the corresponding entropy scales linearly with the lattice size at zero temperature.
Pressure-Induced Superconductivity in Flat-Band Kagome Compounds Pd3P2(S1 – x
Se
x
)8
Authors: Li Shuo , Han Shuo , Yan Shaohua , Cui Yi , Wang Le , Wang Shanmin , Chen Shanshan , Lei Hechang , Yuan Feng , Zhang Jinshan , Yu Weiqiang
Published: June 2022

We performed high-pressure transport studies on the flat-band Kagome compounds, Pd3P2(S1 – x
Se
x
)8 (x = 0, 0.25), with a diamond anvil cell. For both compounds, the resistivity exhibits an insulating behavior with pressure up to 17 GPa. With pressure above 20 GPa, a metallic behavior is observed at high temperatures in Pd3P2S8, and superconductivity emerges at low temperatures. The onset temperature of superconducting transition T
C rises monotonically from 2 K to 4.8 K and does not saturate with pressure up to 43 GPa. For the Se-doped compound Pd3P2(S0.75Se0.25)8, the T
C is about 1.5 K higher than that of the undoped one over the whole pressure range, and reaches 6.4 K at 43 GPa. The upper critical field with field applied along the c axis at typical pressures is about 50% of the Pauli limit, suggesting a 3D superconductivity. The Hall coefficient in the metallic phase is low and exhibits a peaked behavior at about 30 K, which suggests either a multi-band electronic structure or an electron correlation effect in the system.
Self-Supervised Graph Neural Networks for Accurate Prediction of Néel Temperature
Authors: Kong Jian-Gang , Li Qing-Xu , Li Jian , Liu Yu , Zhu Jia-Ji
Published: June 2022

Antiferromagnetic materials are exciting quantum materials with rich physics and great potential for applications. On the other hand, an accurate and efficient theoretical method is highly demanded for determining critical transition temperatures, Néel temperatures, of antiferromagnetic materials. The powerful graph neural networks (GNNs) that succeed in predicting material properties lose their advantage in predicting magnetic properties due to the small dataset of magnetic materials, while conventional machine learning models heavily depend on the quality of material descriptors. We propose a new strategy to extract high-level material representations by utilizing self-supervised training of GNNs on large-scale unlabeled datasets. According to the dimensional reduction analysis, we find that the learned knowledge about elements and magnetism transfers to the generated atomic vector representations. Compared with popular manually constructed descriptors and crystal graph convolutional neural networks, self-supervised material representations can help us to obtain a more accurate and efficient model for Néel temperatures, and the trained model can successfully predict high Néel temperature antiferromagnetic materials. Our self-supervised GNN may serve as a universal pre-training framework for various material properties.
Effects of magnetic monopole charge on Joule–Thomson expansion of regular Ayón Beato–García black hole
Authors: Feng Qi-Min , Pu Jin , Jiang Qing-Quan
Published: June 2022

We investigate Joule–Thomson (J–T) expansion process of the regular Ayón Beato–García (ABG) black hole, and compare the J–T expansion process between the regular ABG black hole and the singular AdS black holes. We find that the inversion curves are unclosed and closely related to magnetic monopole charge (MMC) in the black hole solution. The results show that the temperature decreases/increases with the increase of MMC parameter at low/high pressure, in contrast to a branch of the inversion curves for singular AdS black holes. The ratio between the minimum inversion temperature and the critical temperature is also greater than that of any known ratio of singular AdS black holes. In addition, the minimum inversion mass is greater than the minimum mass, so there are some isenthalpic curves without inversion points below the inversion curves, which means that the regular black hole is always in heating process. In contrast of singular charged AdS black holes, the isenthalpic curves cannot exist below the inversion curves, because the event horizon cannot be defined here. Furthermore, we obtain that the minimum inversion mass and the minimum mass depend only on MMC parameter. By fixing the parameters of MMC and the black hole mass, we find that a repulsive core near the origin of the regular black hole may lead to different results from that of the singular AdS black holes in the J–T expansion process.
Student understanding of thermodynamic processes, variables and systems
Authors: Brown Benjamin , Singh Chandralekha
Published: June 2022

This work focuses on students’ common struggles with thermodynamic processes, variables and systems found via a research-based multiple-choice survey. The analysis of data from more than a thousand students using the validated survey administered at six different higher education institutions in the US shows that not only introductory but also advanced physics students have many common difficulties with these concepts after traditional lecture-based instruction in relevant concepts. Findings related to common challenges encountered by students with thermodynamic processes, variables and systems can help instructors teaching these courses improve student understanding of these concepts. These findings can also be valuable for developing effective evidence-based curricula and pedagogies to reduce student difficulties and help students develop a solid grasp of these fundamental thermodynamic concepts.
An ultra-thin transparent multi-functional sensor based on silk hydrogel for health monitoring
Authors: Qiu Yu , Wang Yi-Lin , Tang Wen-Jie , Wu Tong-Jing , Huang Peng , Yu Qian , Xu Li , Zhang Xiao-Sheng
Published: June 2022

With the gradual improvement of people’s health awareness, wearable devices occupy an important position in daily health care and human physiological activity monitoring. As traditional silicon-based electronic products face problems such as interface mismatch, silk fibroin has gradually become an alternative choice for next-generation wearable electronic devices due to its excellent performance. Herein, an ultra-thin transparent and flexible multi-functional sensor based on silk hydrogel with self-patterned microstructure is proposed. The silk hydrogel exhibits superior transparency (>82%) and thin thickness (∼100 μm). Furthermore, the self-patterned microstructure on the silk hydrogel surface is beneficial for the high sensitivity of pressure sensing response (1.6 kPa−1). This device exhibits advantageous performance on temperature (top sensitivity of 6.25% °C−1) and humidity (top sensitivity of 0.16% RH−1) sensing response. It also shows fast response (0.16 s) and durable stability (over 2000 dynamic cycles). Moreover, this device can be applied to monitor human facial expression, joint movements, temperature change, breathing and other health indicators. It is worth mentioning that this multi-functional sensor can monitor the signal of breathing and throat, so it can be applied to the clinical physiological activity monitoring of patients with upper respiratory tract infection. In addition, we also demonstrate a grasping and relaxing experiment of intelligent manipulator to verify the pressure and temperature sensing performance, providing a possibility for its application in the field of prosthetics. According to these advantages, the reported ultra-thin transparent multi-functional sensor based on silk hydrogel has broad prospects in the fields of health monitoring, intelligent prosthetics, and electronic skin, etc.
Flexible V-shaped piezoelectric-triboelectric device for biomechanical energy harvesting and sensing
Authors: Naval Sourav , Beigh Nadeem Tariq , Mukherjee Dibyajyoti , Jain Ankesh , Mallick Dhiman
Published: June 2022

The vast proliferation of wearables and smart sensing devices in the last decade has created an immense demand for new and efficient powering solutions. The research focus has shifted towards developing simple, cost-effective, flexible device topologies capable of capturing kinetic energy associated with the human body. Piezoelectric and triboelectric mechanisms are widely employed to convert biomechanical energy to electrical power due to their inherent merits in terms of affordable designs and high energy conversion efficiencies. In this work, we propose a flexible hybrid generator topology incorporating both piezoelectric and triboelectric mechanisms to achieve high electrical output from human motion. To enhance the efficiency and obtain a symmetric output, dual triboelectric generators are employed, which generate time-multiplexed output across the same set of electrodes. The device displays a characteristic ability to distinguish between different body movements as its output depends on the contact area as well as the pressure generated by the motion. This creates numerous avenues for employing the device in self-powered tactile sensing applications. The unique single substrate design makes the device robust and increases its longevity. The V-shaped prototype having an active area of 3.5 cm × 2 cm, is tested under a wide range of biomechanical stimuli, including touching, tapping, and pressing motions. The practical applications of the proposed device as an add-on patch on fabrics, as an in-sole device, and for powering commercial electronics are demonstrated. Apart from this, the reported generator can also fuel low-power devices from various other day-to-day human activities.
Electric field induced spin resolved graphene p–n junctions on magnetic Janus VSeTe monolayer
Authors: Hu Yang , Ma Yongjie , Ren Weiwei , Pang Rui , Hao Dongfeng , Han Xiaoyu , Wang Fei , Cui Bin , Li Chong , Jia Yu
Published: June 2022

Graphene basedp–njunctions exhibit intriguing and distinctive electronic properties, making them promising candidates for spintronic and spin photonic devices. While the attendant realization of magnetized graphenep–njunctions is highly desirable. Using first-principles calculations, we show that in the presence of magnetic proximity coupling effect of graphene supported on Te-termination magnetic Janus VSeTe monolayer (VSeTe/G), the graphene is readily spin-polarized and the Dirac bands near Fermi level keep intact. More interestingly, the external electric field (Eex) could significantly influence the bands of the spin down channel near Fermi level, due to the dominant electronic Coulomb screening effect. When theEexexceeds 0.35 eV Å−1with opposite direction to intrinsic dipole moment, the VSeTe/G heterostructure would turn intontype doping from the initial lightptype doping in the spin down channel. However, those of the spin up channel in the vicinity of Fermi level are inert and still preserve initialptype against external electric field. In terms of such distinctive differences between the Dirac bands in the spin up and spin down channels, we propose a featured spin resolved graphenep–njunctions on magnetic Janus VSeTe by applying appropriate external electric field. Our findings are generally applicable to other similar magnetic Janus systems (i.e. graphene/FeICl) and might provide a feasible strategy to realize stable spin resolved graphenep–njunctions extendedly.
British nuclear test veteran family trios for the study of genetic risk
Authors: Rake Christine , Gilham Clare , Scholze Martin , Bukasa Laurette , Stephens Jade , Simpson Jayne , Peto Julian , Anderson Rhona
Published: June 2022

The risk of radiation effects in children of individuals exposed to ionising radiation remains an ongoing concern for aged veterans of the British nuclear testing programme. The genetic and cytogenetic family trio (GCFT) study is the first study to obtain blood samples from a group of British nuclear test veterans and their families for the purposes of identifying genetic alterations in offspring as a consequence of historical paternal exposure to ionising radiation. In this report, we describe the processes for recruitment and sampling, and provide a general description of the study population recruited. In total, blood samples were received from 91 (49 test and 42 control) families representing veteran servicemen from the army, Royal Air Force and Royal Navy. This translated to an overall response rate of 14% (49/353) for test veterans and 4% (42/992) for control veterans (excluding responders known to be ineligible). Due to the lack of dose information available, test veterans were allocated to a three-point exposure rank. Thirty (61%) test veterans were ranked in the lower group. Nineteen (39%) of the 49 test veterans were classified in the mid (5 veterans; 10%)/high (14 veterans; 29%) exposure ranks and included 12 veterans previously identified as belonging to the special groups or listed in health physics documents. An increased number of test veteran families (20%), compared with control families (5%), self-reported offspring with congenital abnormalities (p = 0.03). Whether this observation in this small group is reflective of the entire UK test veteran cohort or whether it is selection bias requires further work. The cohort described here represent an important and unique family trio grouping whose participation is enabling genetic studies, as part of the GCFT study, to be carried out. The outcomes of these studies will be published elsewhere. ISRCTN Registry: 17461668.
Measurement method of a microspring-supported force plate with an external laser displacement meter
Authors: Sugimoto Takumi , Kawasaki Yuta , Toda Hirofumi , Takahashi Hidetoshi
Published: June 2022

Ground reaction force (GRF) is a significant factor for the evaluation of animal locomotion. Recently, micro force plates have been implemented as a GRF measurement method for tiny insects. Previous micro force plates were highly sensitive, but fragile and laborious to fabricate, because of the use of strain-sensing elements. Here, we applied high-resolution 3D printing and a noncontact displacement meter to a micro force plate for a fruit fly. 3D printing is suitable for easier, reproducible, and complex three-dimensional fabrication so that a force plate structure, which consists of a plate and four supporting 3D microsprings, is developed as an integrated unit. By detecting the displacement of the plate centre externally, when a fruit fly lands on the plate surface, the vertical GRF of the whole device is calculated via the spring constant. The force plate is sufficiently tough due to the supporting 3D microsprings. The spring constant of the microspring is designed to be approximately 5.98 N m−1, which enables a high-resolution external laser displacement meter to realize a force resolution of less than 1/50 of the body weight of a fruit fly. Providing that the four springs have the same spring constant and the displacement meter aligns at the plate centre, in principle, there is no positional error when converting from displacement to force. However, fabrication error does lead to spring constant differences. Here, we theoretically and experimentally determined the measurement point of the displacement sensor where the positional error caused by the difference in the spring constant of the four microsprings is compensated for. It was confirmed in the experiment that the calibration process improved the position error to be within ±1.5%. Finally, we demonstrated the GRF measurement of a fruit fly. The average GRF was 6.5 μN, which was equal to the weight of a fruit fly. Our proposed device can help evaluate the biomechanics of tiny insects.
90Y-CA/SPIONs for dual magnetic hyperthermia-radionuclide nanobrachytherapy of solid tumours
Authors: Vukadinović Aleksandar , Milanović Zorana , Ognjanović Miloš , Janković Drina , Radović Magdalena , Mirković Marija , Karageorgou Maria-Argyro , Bouziotis Penelope , Erić Slavica , Vranješ-Đurić Sanja , Antić Bratislav , Prijović Željko
Published: June 2022

Radiolabelled superparamagnetic iron oxide nanoparticles (SPIONs) are a promising nanomaterial for the development of dual radiation/hyperthermia cancer therapy. To that purpose, flower-shaped SPIONs with an exceptional heating capability were synthesised and coated with citrate, dextran or (3-aminopropyl)triethoxysilane. Both non-coated and coated SPIONs were nontoxic to CT-26 mouse colon cancer cells up to 1.0 mg ml−1
in vitro. In an oscillating magnetic field, citrate-coated SPIONs (CA/SPIONs) displayed the highest heating rate (SAR ∼ 253 W g−1) and the strongest hyperthermia effects against CT-26 cells. Labelling of the CA/SPIONs by the 90Y radionuclide, emitting β− radiation with an average/maximum energy of 0.94/2.23 MeV, and deep tissue penetration generated 90Y-CA/SPIONs intended for the therapy of solid tumours. However, intravenous injection of 90Y-CA/SPIONs in CT-26 xenograft-bearing mice resulted in low tumour accumulation. On the contrary, intratumoural injection resulted in long-term retention at the injection site. A single intratumoural injection of 0.25 mg CA/SPIONs followed by 30-min courses of magnetic hyperthermia for four consecutive days caused a moderate antitumour effect against CT-26 and 4T1 mouse tumour xenografts. Intratumoural application of 1.85 MBq/0.25 mg 90Y-CA/SPIONs, alone or combined with hyperthermia, caused a significant (P ≤ 0.01) antitumour effect without signs of systemic toxicity. The results confirm the suitability of 90Y-CA/SPIONs for monotherapy or dual magnetic hyperthermia-radionuclide nanobrachytherapy (NBT) of solid tumours.
Joint image reconstruction algorithm in Compton cameras
Authors: Roser J , Barrientos L , Bernabéu J , Borja-Lloret M , Muñoz E , Ros A , Viegas R , Llosá G
Published: June 2022

Objective. To demonstrate the benefits of using an joint image reconstruction algorithm based on the List Mode Maximum Likelihood Expectation Maximization that combines events measured in different channels of information of a Compton camera. Approach. Both simulations and experimental data are employed to show the algorithm performance. Main results. The obtained joint images present improved image quality and yield better estimates of displacements of high-energy gamma-ray emitting sources. The algorithm also provides images that are more stable than any individual channel against the noisy convergence that characterizes Maximum Likelihood based algorithms. Significance. The joint reconstruction algorithm can improve the quality and robustness of Compton camera images. It also has high versatility, as it can be easily adapted to any Compton camera geometry. It is thus expected to represent an important step in the optimization of Compton camera imaging.
A deep learning approach to estimate pulse rate by remote photoplethysmography
Authors: Lampier Lucas Côgo , Valadão Carlos Torturella , Silva Leticia Araújo , Delisle-Rodríguez Denis , Caldeira Eliete Maria de Oliveira , Bastos-Filho Teodiano Freire
Published: June 2022

Objective. This study proposes a U-net shaped Deep Neural Network (DNN) model to extract remote photoplethysmography (rPPG) signals from skin color signals to estimate Pulse Rate (PR). Approach. Three input window sizes are used in the DNN: 256 samples (5.12 s), 512 samples (10.24 s), and 1024 (20.48 s). A data augmentation algorithm based on interpolation is also used here to artificially increase the number of training samples. Main results. The proposed model outperformed a prior-knowledge rPPG method by using input signals with window of 256 and 512 samples. Also, it was found that the data augmentation procedure only increased the performance for the window of 1024 samples. The trained model achieved a Mean Absolute Error (MAE) of 3.97 Beats per Minute (BPM) and Root Mean Squared Error (RMSE) of 6.47 BPM, for the 256 samples window, and MAE of 3.00 BPM and RMSE of 5.45 BPM for the window of 512 samples. On the other hand, the prior-knowledge rPPG method got a MAE of 8.04 BPM and RMSE of 16.63 BPM for the window of 256 samples, and MAE of 3.49 BPM and RMSE of 7.92 BPM for the window of 512 samples. For the longest window (1024 samples), the concordance of the predicted PRs from the DNNs and the true PRs was higher when applying the data augmentation procedure. Significance. These results demonstrate a big potential of this technique for PR estimation, showing that the DNN proposed here may generate reliable rPPG signals even with short window lengths (5.12 s and 10.24 s), suggesting that it needs less data for a faster rPPG measurement and PR estimation.
A helical grid equivalent circuit model for an intra-layer no-insulation coil
Authors: Wang Kangshuai , Wang Qiuliang , Liu Jianhua , Qin Lang , Zhou Benzhe , Wang Lei , Zhang Zili , Dai Yinming
Published: June 2022

The intra-layer no-insulation (LNI) coil, which has the advantages of self-protection and high magnetic field homogeneity, is of great potential in HTS NMR and MRI applications. Compared to the more commonly-used double-pancake coils, the transient characteristics are more complex due to additional axial current. While the present circuit model cannot accurately describe the geometry of the LNI coil and the internal characteristics of each turn of the coil, a helical grid equivalent circuit model with consideration of types of mutual inductances is proposed in this paper. In the circuit model, details of the coil are characterized with subdivided helical surface elements in each turn, and each helical surface element can be equivalent to corresponding circuit parameters. The circuit model is verified by a comparison experiment with an intra-layer insulation coil. And elaborate current distributions in each turn of the LNI coil can be obtained with this circuit model. Analysis results demonstrate that the azimuthal current and the axial current are always symmetrically distributed about the middle plane, and the radial current is always anti-symmetrically distributed about the midplane. The circuit model can be used to simulate the quench electromagnetic characteristics of the LNI coil in the future.
Low-noise second-order gradient SQUID current sensors overlap-coupled with input coils of different inductances
Authors: Xu Da , Li Jinjin , Wang Shijian , Ma Mengze , Cao Wenhui , Wang Xueshen , Zhang Mingyu , Zhao Jianting , Zhong Qing
Published: June 2022

In this study, we developed a series of second-order gradient overlap-coupling octagonal superconducting quantum interference device (SQUID) current sensors for transition edge sensor (TES) applications. According to the requirements of TESs, we designed various parameters of SQUID current sensors, including different Josephson junction (JJ) sizes, different hysteresis and screening parameters, input coils with different inductances. The superconducting loop, input coil, and feedback coil of the SQUID current sensors adopt a second-order gradient structure, which can effectively enhance their anti-interference electromagnetic capability. Further, all the coupling structures between the superconducting loop and input/feedback coil adopt overlap-coupling octagonal structures, which can effectively enhance the coefficient of coupling mutual inductance. A series of second-order gradient SQUID current sensors overlap-coupled with input coils of 1.5, 2.5, and 5.5 turns based on Nb/Al–AlO
x
/Nb JJs were successfully fabricated on 2 inch silicon wafers by optimising the fabrication processes. From the simulation results, a minimal magnetic coupling factor of 0.02 between the feedback coil and input coil is obtained in the overlapped structure of the SQUID current sensor with an input coil of 1.5 turns; thus the magnetic interference between the feedback coil and input coil in this design is negligible. According to the measurement results at liquid–helium temperatures, SQUID current sensors with second-order gradient overlap-coupling octagonal structures have an excellent capability to weaken environmental electromagnetic interference. The SQUID current sensor with an input coil of 5.5 turns has the smallest current sensitivity, 2.4 μA/Φ0 and lowest current noise, 1 pA (√Hz)−1 compared with those of other input coils of different turns. The SQUID current sensor with an input coil of 2.5 turns has the lowest flux noise, 0.3 μΦ0 (√Hz)−1, and the lowest coupled noise energy, 11 h, among all the three different input coils, which are balanced results between the input inductance and the device noise. SQUID current sensors with second-order gradient overlap-coupling octagonal structures show low flux noise, low current noise, and low coupled noise energy, which can be compared with the state-of-art SQUID current sensor worldwide, and can satisfy the requirements of TES applications.