bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of the shape of a conducting chamber on the stability of rigid ballooning modes in a mirror trap
Authors: Zeng Qiusun , Kotelnikov Igor
Published: May 2024

MHD stabilization of flute and ballooning modes in an axisymmetric mirror trap is studied under the assumption of strong finite Larmor radius effect that suppresses all perturbations with azimuthal numbers

m
⩾
2

and makes the m = 1 mode ‘rigid’. The rigid mode can be effectively suppressed using perfectly conducting lateral wall without any additional means of stabilization or in combination with end MHD anchors. Numerical calculations were carried out for an anisotropic plasma produced in the course of neutral beam injection into the minimum of the magnetic field at the right angle to the trap axis. The stabilizing effect of the conducting shell made of a straightened cylinder is compared with a proportional chamber, which, on an enlarged scale, repeats the shape of the plasma column. It is confirmed that for convincing wall stabilization of the rigid modes, the plasma beta (β, the ratio of the plasma pressure to the magnetic field pressure) must exceed some critical value

β

cr
2

. When conducting lateral wall is combined with conducting end plates imitating MHD end anchors, there are two critical betas and, respectively, two stability zones

β
<

β

cr
1

and

β
>

β

cr
2

that can merge, making the entire range

0
<
β
<
1

of betas allowable for stable plasma confinement. The dependence of the critical betas on the plasma anisotropy, mirror ratio, width of the vacuum gap between the plasma column and the lateral wall, radial pressure profile and the axial magnetic field profile is examined.
Designing, modeling and controlling the angular bending of a foldable soft actuator without using a curvature sensor
Authors: My Nu Ho Thi , Viet Luong Quoc , Truyen Le The
Published: May 2024

Soft actuators have recently attracted considerable attention owing to their inherent flexibility and adaptability. Nevertheless, for a soft robot to successfully engage with its surroundings and perform tasks with optimal effectiveness, it encounters a range of obstacles, including the need for precise and skillful movement, the capacity to perceive its own position and motion and the ability to effectively regulate its flexible structures. Researchers have developed techniques to integrate curvature sensors onto flexible devices, enabling them to detect and react to their positions. However, the integration of curvature sensors into flexible structures presents a substantial challenge in the structural manufacturing process. To address these concerns, this article presents a technique for designing, dynamic modeling and controlling the bending angle of foldable soft actuator without the need for curvature sensors. An optimal design for the geometric dimensions of the soft structure utilizing origami concepts to guarantee the requisite bending properties is suggested. A model-based control method that considers both the motion dynamic and the air dynamic is proposed for controlling the angular bending of the actuator. The motion dynamic was developed using the constant volume principle of the elastomer material and the neo-Hookean hyperelastic theory to establish the correlation between the applied pressure and bending angle. This dynamic model incorporates both the hyperelastic material characteristics of silicone rubber and the geometry of the actuator. Soft actuators have variations in the air chamber’s volume during operation and accurately measuring this variation is challenging. In order to tackle this problem, the fuzzy active disturbance rejection controller is used to predict these variations. The controller possesses exceptional position-tracking capability. This control strategy exhibited excellent responsiveness throughout the range of steady-state error values from approximately 1°–2°. Removing the curvature sensor increases the longevity of this soft actuator and promotes the efficiency of the manufacturing process, hence enhancing the practical application possibilities for the soft actuator made from super elastic material.
A Novel Two-dimensional Low-redundancy Array Design for Solar Radio Imaging
Authors: Zhang 张 Weidan 卫丹 , Wang 王 Bing 冰 , Wu 武 Zhao 昭 , Lu 路 Guang 光 , Chen 陈 Yao 耀 , Fabao 严 Yan 发宝
Published: May 2024

The radioheliograph is an extensive array of antennas operating on the principle of aperture synthesis to produce images of the Sun. The image acquired by the telescope results from convoluting the Sun’s true brightness distribution with the antenna array’s directional pattern. The imaging quality of the radioheliograph is affected by a multitude of factors, with the performance of the “dirty beam” being simply one component. Other factors such as imaging methods, calibration techniques, clean algorithms, and more also play a significant influence on the resulting image quality. As the layout of the antenna array directly affects the performance of the dirty beam, the design of an appropriate antenna configuration is critical to improving the imaging quality of the radioheliograph. Based on the actual needs of observing the Sun, this work optimized the antenna array design and proposed a two-dimensional low-redundancy array. The proposed array was compared with common T-shaped arrays, Y-shaped arrays, uniformly spaced circular arrays, and three-arm spiral arrays. Through simulations and experiments, their performance in terms of sampling point numbers, UV coverage area, beam-half width, sidelobe level, and performance in the absence of antennas are compared and analyzed. It was found that each of these arrays has its advantages, but the two-dimensional low-redundancy array proposed in this paper performs best in overall evaluation. It has the shortest imaging calculation time among the array types and is highly robust when antennas are missing, making it the most suitable choice.
Power and isotope effects in the ITER baseline scenario with tungsten and tungsten-equivalent radiators in DIII-D
Authors: Sips A.C.C. , Turco F. , Greenfield C.M. , Schmitz L. , Luce T. , Odstrčil T. , McLean A. , Bykov I. , Hyatt A. , Osborne T.
Published: May 2024

Experiments in DIII-D document the ITER Baseline Scenario (IBS) at q
95 ∼ 3 and P
IN/P
LH ∼ 1–2, in both deuterium and hydrogen utilizing Kr and Xe as Tungsten-equivalent radiators. The power threshold for H-mode operation (P
LH) was determined experimentally without added impurities and found to be about a factor of two higher than the scaling law. In recent IBS experiments in deuterium, intrinsic levels of metals such as Tungsten (W) or molybdenum and inconel are present that reduce the pedestal pressure by 20%–25%. A complete radiative collapse of deuterium IBS plasmas occurs at W core concentrations C
W = 10−5. Simulations show that for core temperatures expected for ITER, the plasmas would not have a radiative collapse at C
W = 1 × 10−5, moreover Q = 8–10 would still be achieved for C
W up to 3 × 10−5. In contrast to deuterium, the IBS in hydrogen is not affected by intrinsic high-Z impurities, indicating that hydrogen H-modes in ITER may not inform the D-T phase with respect to W accumulation and discharge survival. Compared to deuterium, the pedestal pressure in hydrogen is ∼25% lower, with much higher ELM frequency of 150 Hz, decreasing with input power. Krypton was injected in a matrix scan of input power and impurity flow in IBS hydrogen discharges. Krypton impurity density profiles in hydrogen are similar to deuterium plasmas, but at Kr flows that are 2–3 times higher for the same input power. Krypton is transported into the core and affects the whole radius; at the highest injection rates a radiative collapse occurs at core radiation fractions of 0.3–0.35, consistent with the expected maximum W radiation fraction for ITER core plasmas. Comparing the results with previous International Tokamak Physics Activity database studies of the IBS confirms that at higher radiation fraction due to high-Z impurities, a drop in H
98 of >10% is observed. On the other hand, the results using Kr as a W-equivalent radiator indicate that metal (W) devices at lower core temperatures than ITER may provide overly pessimistic performance extrapolations to ITER for deuterium-tritium operation. The new DIII-D results support a more attractive option for the ITER Research Plan with a short hydrogen phase for system commissioning, transitioning to deuterium operations as soon as possible to provide relevant conditions for deuterium-tritium operations.
New methodology for estimating the influence of Cu content of Ferrous Scrap materials in the Total Cost of Operation (TCO) of scrap mix in Electric Arc Furnace steelmaking
Authors: Nuñez E. , Priyadarshi H. , Picco M. , Vicente A.
Published: May 2024

Scrap is the main raw material of the electric arc furnace (EAF) route of steelmaking and an important one in the primary route. The decarbonisation commitment acquired by the most relevant steelmaking companies, will only increase the amount of scrap used by both routes, making it a critical component to succeed in the worldwide challenge of reducing CO2 emissions. While being a very relevant material, scrap characterisation is complex due to its heterogeneity, but furthermore, its quality is worsening as its demand increases. This includes the sterile content, such as copper. Higher sterile content scrap comes at a lower price, while scrap with a lower content in undesired elements is most costly. Being able to balance the cost and benefit of purchasing scrap with a higher or lower content of copper with a respective, lower or higher purchase cost would be of interest to optimise the mix and produce the required quality steel at the lowest possible cost. Nowadays, this cost benefit analysis can only be done by performing Total Cost of Operation (TCO) calculations that require a considerable amount of information, including but not limited to the complete chemical composition of scrap, market parameters, production forecast and other relevant data; moreover, involving an arduous optimization process. Based on a parametric study of the TCO calculation, this work proposes a mathematical model to estimate the impact on the TCO of a predefined scrap mix when only modifying the specifics of one given scrap type. The results would facilitate the decision making by comparing the two scenarios as a factor of cost. This mathematical model can be easily programmed and requires only 5 parameters to be run, while providing a low error result.
Biochar as a slag foaming agent in EAF – A novel experimental setup
Authors: Hoikkaniemi E , Sulasalmi P , Visuri V-V , Fabritius T
Published: May 2024

Slag foaming practice is employed widely in electric arc furnace steelmaking to improve the energy efficiency, protect the furnace structures and reduce noise pollution. Slag foaming is typically launched by injecting fossil-based carbonaceous material (e.g. coke dust) into the melt. In this study, a novel laboratory-scale experimental setup was used for studying the substitution of fossil carbon by biochar as slag foaming agent. The setup was equipped with an injection device for feeding carbon and a camera system for observing the foaming phenomenon and recording the process. A set of experiments was conducted for studying the foaming in slag-carbon systems using two carbonaceous materials: 1) coke dust was used as a reference material and 2) a high-quality biochar was used as a possible replacement. In the experiments, sufficient foaming was achieved with both of the carbonaceous materials. The biochar produced almost equal foaming behavior as coke dust. The results indicate that biochar could be used to substitute carbon for slag foaming in the EAF.
Antiferromagnetism in two-dimensional materials: progress and computational challenges
Authors: Olsen Thomas
Published: May 2024

We present a perspective on the status of antiferromagnetism in two-dimensional (2D) materials. Various types of spin-compensated orders are discussed and include non-collinear order, spin spirals and altermagnetism. Spin–orbit effects ultimately determine, whether compounds exhibit long range order, Kosterlitz-Thouless physics, or multiferroic properties and we discuss the basic magnetic prototypes that may arise in 2D materials depending on the magnetic anisotropy and ordering vector. A summary of 2D antiferromagnets that have been characterized experimentally is provided—with particular emphasis on magnetic anisotropies and Neel temperatures. We then outline the ingredients needed to describe the magnetic properties using density functional theory. In particular, the systematic determination of magnetic ground states from the generalized Bloch theorem and the magnetic force theorem, which may be used to calculate magnetic excitations from the Heisenberg model with parameters determined from first principles. The methods are exemplified by application to the monolayer helimagnet NiBr2. Finally, we present a summary of predicted and prospective 2D antiferromagnets and discuss the challenges associated with the prediction of Néel temperatures from first principles.
Study on the hot deep drawing performance and microstructural evolution of AZ91D magnesium alloy sheets
Authors: Shi Yongze , Deng Peiran , Hou Jinyu , Chong Xiwen , Wang Yuxuan
Published: May 2024

Magnesium alloys are attractive because of their low density and high specific strength and stiffness; however, secondary phase strengthening and the low number of slip systems lower formability especially for the strongest magnesium alloys such as AZ91D. The formability of AZ91D sheets is investigated through orthogonal experiments, which show that AZ91D has no deep drawing properties at room temperature and that plastic forming is only possible under hot forming conditions. When the temperature is increased from room temperature to 400 °C, the limiting drawing ratio of the sheet increases significantly to 1.91, and the thinning rate reaches a minimum value of 6% at approximately 400 °C because of the improved plastic flowability. The optimum process parameters for hot deep drawing are a temperature of 400 °C, blank holder force of 5 kN, and punch speed of 3 mm s−1. The microstructural evolution shows that plastic deformation of the AZ91D magnesium alloy at high temperatures is markedly accommodated by twinning and that, with heating, this twinning deformation mechanism is activated and overcomes the hindrances of the reinforcing phases to achieve better forming properties.
Experimental confirmation of the linear relation between plasma current and external vertical magnetic field in EXL-50 spherical torus energetic electron plasmas
Authors: DONG 董 Lili 力立 , WANG 王 Mingyuan 明远 , LIU 刘 Wenjun 文军 , SHI 石 Yuejiang 跃江 , DONG 董 Jiaqi 家齐 , GUO 郭 Dong 栋 , SUN 孙 Tiantian 恬恬 , GU 顾 Xiang 翔 , SONG 宋 Xianming 显明 , YUAN 袁 Baoshan 保山 , PENG 彭 Yueng-Kay Martin 元凯 , Team the ENN
Published: May 2024

A three-fluid equilibrium plasma with bulk plasma and energetic electrons has been observed on the Xuanlong-50 (EXL-50) spherical torus, where the energetic electrons play a crucial role in sustaining the plasma current and pressure. In this study, the equilibrium of a multi-fluid plasma was investigated by analyzing the relationship between the external vertical magnetic field (B
V), plasma current (I
p), the poloidal ratio (β
p) and the Shafranov formula. Remarkably, our research demonstrates some validity of the Shafranov formula in the presence of multi-fluid plasma in EXL-50 spherical torus. This finding holds significant importance for future reactors as it allows for differentiation between alpha particles and background plasma. The study of multi-fluid plasma provides a significant reference value for the equilibrium reconstruction of burning plasma involving alpha particles.
Relationship between deposition techniques and nanoparticle dispersions for flexible and printed electronics
Authors: Oliveira P Q , Arbi R , Munir M , Patil L , Turak A Z
Published: May 2024

Reverse micelles composed of polystyrene-b-poly(2-vinylpyiridine) have been used to synthesize nanoparticles composed of a wide range of materials, including metals, metal oxides, dielectrics, semiconductors perovskites, and core–shell nanoparticles. In this contribution, we examine the effect of deposition parameters on two-dimensional nanoparticle arrangements from colloidal solutions created using spin coating, dip coating, slot-die coating, and electrospray deposition. Despite the importance of achieving uniform coatings of ordered arrays of colloidal particles, previous studies have not thoroughly addressed this challenge. We show that the adjustability of interparticle distance depends on the deposition technique used and only occurs within the stable defect-free operating window of the deposition parameters. Establishing the specific operating window for each technique for a model system, we propose general guidelines that can be used for ensuring uniform coatings regardless of precursor loading and provide a guide for adjusting the deposition conditions when coating defects occur. We introduces a novel application of ellipsometry to evaluate interparticle spacing in nanoparticle arrays, enhancing our ability to assess film uniformity, allowing for quick and easy tuning of nanoparticle dispersion. Comparisons between spin, dip, and slot-die coating techniques reveal insights into the correlation between interparticle spacing and ordering, highlighting the importance of fitting relationships for various coating samples. This comprehensive comparison and discussion provide a roadmap for future research, outlining current challenges and trends and offering insights into achievable spacings and ordering in coating processes. This allows the classification of various deposition techniques with respect to their suitability for tailored applications.
Dewetting-assisted inkjet printing and optimized solvent mixture of Cd-free InP quantum dots for high-resolution pixel-pattern
Authors: Lee Youngwoo , Jeong Yong-Cheol
Published: May 2024

Direct-printed quantum dot (QD) patterns utilizing inkjet method are a next-generation alternative to achieve high-resolution quantum dot light-emitting diodes (QLED). However, research on high-resolution pixel patterns is still limited due to issues such as thickness uniformity. In this study, we explored the feasibility of direct printing QLEDs to attain high-resolution pixel-patterned displays. Here, we successfully fabricated arrays of green QLED devices with a resolution of 200 pixels per inch, employing a precise 1 pL fine printer nozzle and optimizing ink formulation to achieve superior surface roughness and uniformity at the desired thickness. The inkjet-printed QD layers demonstrated a surface roughness of 1.9 nm and a flatness ratio of 0.2, comparable to those achieved through conventional spin-coating processes. This investigation offers the potential for extending the methodology to the fabrication of cost-effective, high-resolution full-color QLED displays.
Sur7 mediates a novel pathway for PI4,5P2 regulation in C. albicans that promotes stress resistance and cell wall morphogenesis
Authors: Lanze Carla E. , Konopka James B.
Published: May 2024

The human fungal pathogen Candida albicans can cause lethal systemic infections due to its ability to resist stress from the host and to undergo invasive hyphal growth. Previous studies showed that plasma membrane MCC/eisosome domains were important for virulence by promoting the ability of Sur7 to mediate normal cell wall morphogenesis and stress resistance. The sur7Δ mutant displayed abnormal clusters of PI4,5P2, suggesting that misregulation of this lipid underlies the sur7Δ phenotype. To test this, we increased PI4,5P2 levels by deleting combinations of the three PI4,5P2 5′ phosphatase genes ( INP51, INP52, and INP54) and found that some combinations, such as inp51Δ inp52Δ, gave phenotypes similar the sur7Δ mutant. In contrast, deleting one copy of MSS4, the gene that encodes the 5′ kinase needed to create PI4,5P2, reduced the abnormal PI4,5P2 clusters and also decreased the abnormal cell wall and stress sensitive phenotypes of the sur7Δ mutant. Additional studies support a model that the abnormal PI4,5P2 patches recruit septin proteins, which in turn promote aberrant cell wall growth. These results identify Sur7 as a novel regulator of PI4,5P2 and highlight the critical role of PI4,5P2 in the regulation of C. albicans virulence properties.
Drains in Breast Reduction: How Good Is the Recommendation Not to Use Them?
Authors: Behroozian Tara , Hircock Caroline , Dunn Emily , Thoma Achilles
Published: May 2024

A clinical practice guideline (CPG) from the American Society of Plastic Surgeons recommended not to use drains in breast reduction. This CPG was based on 3 randomized controlled trials (RCTs). The objective of this review was to double-check the methodological quality of the 3 RCTs. These RCTs were critically appraised using: (1) the “User's Guide to the Surgical Literature” checklist to critically appraise the methodological quality, (2) the CONSORT guidelines for reporting quality, and (3) the Cochrane risk-of-bias tool 2 (RoB 2) for risk of bias. Weaknesses were identified in all assessments for the 3 RCTs. Items with the poorest adherence in the “User's Guide” included: “Were patients stratified?,” “Was follow-up complete?,” and “Were all clinically important outcomes considered?” The overall adherence to the CONSORT reporting checklist across all 3 studies was moderate with 40.0%, 62.1%, and 48.3% adherence. All 3 RCTs had a similar low to moderate risk of bias, with no areas with a high risk of bias. None of the studies took into consideration a single critical outcome (such as major hematoma) and the outcome's minimally important difference as the basis for the sample size and power calculation of the study. All 3 RCTs additionally lacked clear reporting of treatment effect sizes or precision of estimates. Our re-examination of the evidence questions the recommendation of the CPG. We believe that the recommendation should have been: “We remain uncertain whether drains in breast reduction have a salutary effect.” As such, we recommend that a methodologically robust RCT be conducted to resolve the question of whether drains should be used in breast reduction.
A one-step low-cost molecular test for SARS-CoV-2 detection suitable for community testing using minimally processed saliva
Authors: da Silva Sofia M , Amaral Catarina , Malta-Luís Cláudia , Grilo Diana , Duarte Américo G , Morais Inês , Afonso Gonçalo , Faria Nuno , Antunes Wilson , Gomes Inês , Sá-Leão Raquel , Miragaia Maria , Serrano Mónica , Pimentel Catarina
Published: May 2024

The gold standard for coronavirus disease 2019 diagnostic testing relies on RNA extraction from naso/oropharyngeal swab followed by amplification through reverse transcription-polymerase chain reaction (RT-PCR) with fluorogenic probes. While the test is extremely sensitive and specific, its high cost and the potential discomfort associated with specimen collection made it suboptimal for public health screening purposes. In this study, we developed an equally reliable, but cheaper and less invasive alternative test based on a one-step RT-PCR with the DNA-intercalating dye SYBR Green, which enables the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directly from saliva samples or RNA isolated from nasopharyngeal (NP) swabs. Importantly, we found that this type of testing can be fine-tuned to discriminate SARS-CoV-2 variants of concern. The saliva RT-PCR SYBR Green test was successfully used in a mass-screening initiative targeting nearly 4500 asymptomatic children under the age of 12. Testing was performed at a reasonable cost, and in some cases, the saliva test outperformed NP rapid antigen tests in identifying infected children. Whole genome sequencing revealed that the antigen testing failure could not be attributed to a specific lineage of SARS-CoV-2. Overall, this work strongly supports the view that RT-PCR saliva tests based on DNA-intercalating dyes represent a powerful strategy for community screening of SARS-CoV-2. The tests can be easily applied to other infectious agents and, therefore, constitute a powerful resource for an effective response to future pandemics.
Single-cell transcriptomic analysis identifies infiltrating plasmacytoid dendritic cells in psoriasis epidermis
Authors: Luo Longlong , Cheng Huaitao , Liu Zhuang , Olszewski Pawel , Pasquali Lorenzo , Xu Ning , Enge Martin , Pivarcsi Andor , Sonkoly Enikö
Published: May 2024

Our study unveils the cellular and molecular dynamics in psoriasis epidermis, revealing diverse cell states and their interactions driving inflammation and altered developmental trajectories. Importantly, a previously overlooked plasmacytoid dendritic cell cluster with inflammatory properties was identified in the epidermis of chronic psoriasis lesions, suggesting a potential role for these cells in chronic psoriasis.
Adult Safeguarding Inequalities in Northern Ireland: An Exploratory Study
Authors: Montgomery Lorna , Doyle Laura , Bunting Lisa , Gleghorne Nicole
Published: May 2024

Whilst studies of child welfare inequalities have identified the impact of socio-economic deprivation on child protection rates, little is known about how this relates to intervention with adults who have care and support needs. This article examines the impact of area-level deprivation on adult safeguarding (AS) rates in Northern Ireland (NI). Routinely gathered statistics for community AS referrals (2015–2017) were linked to area-level deprivation across NI using service users’ postcode. The relationship between deprivation and the screening, investigation and safeguarding planning stages of intervention was examined. Our analysis identified a clear social gradient in relation to AS referrals; the higher the level of deprivation, the higher the rates of AS screening and protection plans. Findings for investigations showed more variability. Further research is needed to explore the factors associated with areas of high deprivation that shape AS social work responses. To our knowledge, this is the first time AS rates have been explored in relation to deprivation. The study findings, that structural factors play a significant role in AS interventions, will help to determine how and where social work interventions are best focused, helping to shape policy and AS theory.
Auctions to reveal consumers’ willingness to pay for low-carbon hydrogen projects: combining lessons from renewables and natural-gas industries
Authors: Vazquez Miguel , Hallack Michelle
Published: May 2024

Low-carbon hydrogen is expected to play a key role in realizing net-zero and sustainable development plans. Nonetheless, there is a gap between the cost of producing low-carbon hydrogen and its potential users’ willingness to pay for such hydrogen. To implement support for the development of the industry, we propose using low-carbon hydrogen long-term agreements allocated through auction mechanisms. The objectives are 2-fold: (i) matching supply and demand volumes considering the time horizon and geographical delivery point specification and (ii) allocating the subsidy. This perspective article innovates by proposing a reference price indexed to liquid to natural-gas prices, which is the main product that low-carbon hydrogen aims to substitute. The premium and the production cost are defined through a double-sided auction. This aims to minimize the public policy funds required to incentivize the low-carbon hydrogen market while facilitating long-term agreements and mitigating price risks that may hinder investment.
Emergence of carbonaceous material for hydrogen storage: an overview
Authors: Soni Khemlata , Panwar Narayan Lal , Lanjekar Pranay Rajendra
Published: May 2024

Hydrogen has gained enormous relevance due to its lower carbon footprint and its potential role in balancing energy supply and demand. It is being considered as a sustainable substitute for conventional fuels. The generation of hydrogen using renewable energy sources is still in development, with a significant challenge lying in the efficient and safe storage of hydrogen due to its low energy density. This challenge hinders the widespread adoption of hydrogen. Compression and liquefaction methods of storage face issues of losses that reduce their effectiveness. The technology for hydrogen storage has advanced significantly in the past few years, driven by recent enhancements in synthesizing carbonaceous materials with hydrogen storage capabilities. This article critically reviews novel carbonaceous materials for hydrogen storage, including biochar, activated carbon, carbon nanotubes, carbon nanocomposites, carbon aerogel, fullerenes, MXenes, graphite, graphene and its derivatives. Effective hydrogen adsorption using microporous materials, such as activated carbons, is crucial, sparking interest in economically viable options for hydrogen storage. Despite this, a significant amount of work still needs to be accomplished before the potential and advantages of the hydrogen economy can be fully realized and utilized by manufacturers and academics.
Exact determination of MFPT for random walks on rounded fractal networks with varying topologies
Authors: Liu Yuanyuan , Chen Jing , Sun Weigang
Published: May 2024

Random walk is a stochastic process that moves through a network between different states according to a set of probability rules. This mechanism is crucial for understanding the importance of nodes and their similarities, and it is widely used in page ranking, information retrieval and community detection. In this study, we introduce a family of rounded fractal networks with varying topologies and conduct an analysis to investigate the scaling behaviour of the mean first-passage time (MFPT) for random walks. We present an exact analytical expression for MFPT, which is subsequently confirmed through direct numerical calculations. Furthermore, our approach for calculating this interesting quantity is based on the self-similar structure of the rounded networks, eliminating the need to compute each Laplacian spectrum. Finally, we conclude that a more efficient random walk is achieved by reducing the number of polygons and edges. Rounded fractal networks demonstrate superior efficiency in random walks at the initial state, primarily due to the minimal distances between vertices.
Physiologically informed organismal climatologies reveal unexpected spatiotemporal trends in temperature
Authors: Foulk Aubrey , Gouhier Tarik , Choi Francis , Torossian Jessica L , Matzelle Allison , Sittenfeld David , Helmuth Brian
Published: May 2024

Body temperature is universally recognized as a dominant driver of biological performance. Although the critical distinction between the temperature of an organism and its surrounding habitat has long been recognized, it remains common practice to assume that trends in air temperature—collected via remote sensing or weather stations—are diagnostic of trends in animal temperature and thus of spatiotemporal patterns of physiological stress and mortality risk. Here, by analysing long-term trends recorded by biomimetic temperature sensors designed to emulate intertidal mussel temperature across the US Pacific Coast, we show that trends in maximal organismal temperature (‘organismal climatologies’) during aerial exposure can differ substantially from those exhibited by co-located environmental data products. Specifically, using linear regression to compare maximal organismal and environmental (air temperature) climatologies, we show that not only are the magnitudes of body and air temperature markedly different, as expected, but so are their temporal trends at both local and biogeographic scales, with some sites showing significant decadal-scale increases in organismal temperature despite reductions in air temperature, or vice versa. The idiosyncratic relationship between the spatiotemporal patterns of organismal and air temperatures suggests that environmental climatology cannot be statistically corrected to serve as an accurate proxy for organismal climatology. Finally, using quantile regression, we show that spatiotemporal trends vary across the distribution of organismal temperature, with extremes shifting in different directions and at different rates than average metrics. Overall, our results highlight the importance of quantifying changes in the entire distribution of temperature to better predict biological performance and dispel the notion that raw or ‘corrected’ environmental (and specially air temperature) climatologies can be used to predict organismal temperature trends. Hence, despite their widespread coverage and availability, the severe limitations of environmental climatologies suggest that their role in conservation and management policy should be carefully considered.
Migratory behaviours are risk-sensitive to physiological state in an elevational migrant
Authors: Denryter Kristin , Stephenson Thomas R. , Monteith Kevin L.
Published: May 2024

Accretion of body fat by animals is an important physiological adaptation that may underpin seasonal behaviours, especially where it modulates risk associated with a particular behaviour. Using movement data from male Sierra Nevada bighorn sheep (Ovis canadensis sierrae), we tested the hypothesis that migratory behaviours were risk-sensitive to physiological state (indexed by body fat). Sierra bighorn face severe winter conditions at high elevations and higher predation risk at lower elevations. Given that large body fat stores ameliorate starvation risk, we predicted that having small body fat stores would force animals to migrate to lower elevations with more abundant food supplies. We also predicted that body fat stores would influence how far animals migrate, with the skinniest animals migrating the furthest down in elevation (to access the most abundant food supplies at that time of year). Lastly, we predicted that population-level rates of switching between migratory tactics would be inversely related to body fat levels because as body fat levels decrease, animals exhibiting migratory plasticity should modulate their risk of starvation by switching migratory tactics. Consistent with our predictions, probability of migration and elevational distance migrated increased with decreasing body fat, but effects differed amongst metapopulations. Population-level switching rates also were inversely related to population-level measures of body fat prior to migration. Collectively, our findings suggest migration was risk-sensitive to physiological state, and failure to accrete adequate fat may force animals to make trade-offs between starvation and predation risk. In complex seasonal environments, risk-sensitive migration yields a layer of flexibility that should aid long-term persistence of animals that can best modulate their risk by attuning behaviour to physiological state.
A terpenoids database with the chemical content as a novel agronomic trait
Authors: Li Wenqian , Chen Yinliang , Yang Ruofei , Hu Zilong , Wei Shaozhong , Hu Sheng , Xiong Xinjun , Wang Meijuan , Lubeiny Ammar , Li Xiaohua , Feng Minglei , Dong Shuang , Xie Xinlu , Nie Chao , Zhang Jingyi , Luo Yunhao , Zhou Yichen , Liu Ruodi , Pan Jinhai , Kong De-Xin , Hu Xuebo
Published: May 2024

Natural products play a pivotal role in drug discovery, and the richness of natural products, albeit significantly influenced by various environmental factors, is predominantly determined by intrinsic genetics of a series of enzymatic reactions and produced as secondary metabolites of organisms. Heretofore, few natural product-related databases take the chemical content into consideration as a prominent property. To gain unique insights into the quantitative diversity of natural products, we have developed the first TerPenoids database embedded with Content information (TPCN) with features such as compound browsing, structural search, scaffold analysis, similarity analysis and data download. This database can be accessed through a web-based computational toolkit available at http://www.tpcn.pro/. By conducting meticulous manual searches and analyzing over 10 000 reference papers, the TPCN database has successfully integrated 6383 terpenoids obtained from 1254 distinct plant species. The database encompasses exhaustive details including isolation parts, comprehensive molecule structures, chemical abstracts service registry number (CAS number) and 7508 content descriptions. The TPCN database accentuates both the qualitative and quantitative dimensions as invaluable phenotypic characteristics of natural products that have undergone genetic evolution. By acting as an indispensable criterion, the TPCN database facilitates the discovery of drug alternatives with high content and the selection of high-yield medicinal plant species or phylogenetic alternatives, thereby fostering sustainable, cost-effective and environmentally friendly drug discovery in pharmaceutical farming.

Database URL: http://www.tpcn.pro/
Long-Term Effects of Equal Sharing: Evidence from Inheritance Rules for Land
Authors: Bartels Charlotte , Jäger Simon , Obergruber Natalie
Published: May 2024

What are the long-term economic effects of a more equal distribution of wealth? We investigate consequences of land inequality, exploiting variation in land inheritance rules that traverse political, linguistic, geological and religious borders in Germany. In some German areas, inherited land was to be shared or divided equally among children, while in others land was ruled to be indivisible. Using a geographic regression discontinuity design, we first show a more equal land distribution in areas with equal division; other potential drivers of growth are smooth at the boundary and equal division areas were not historically more developed. Today, equal division areas feature higher average incomes and more entrepreneurship which goes hand in hand with a right-shifted skill, income and wealth distribution. We show evidence consistent with the more even distribution of land leading to more innovative industrial by-employment during Germany’s transition from an agrarian to an industrial economy that, in the long run, led to more entrepreneurship.
Sequence reliance of the Drosophila context-dependent transcription factor CLAMP
Authors: Hodkinson Lauren J , Gross Julia , Schmidt Casey A , Diaz-Saldana Pamela P , Aoki Tsutomo , Rieder Leila E
Published: May 2024

Despite binding similar cis elements in multiple locations, a single transcription factor (TF) often performs context-dependent functions at different loci. How factors integrate cis sequence and genomic context is still poorly understood and has implications for off-target effects in genetic engineering. The Drosophila context-dependent TF chromatin-linked adaptor for male-specific lethal proteins (CLAMP) targets similar GA-rich cis elements on the X-chromosome and at the histone gene locus but recruits very different, locus-specific factors. We discover that CLAMP leverages information from both cis element and local sequence to perform context-specific functions. Our observations imply the importance of other cues, including protein–protein interactions and the presence of additional cofactors.
College students’ perceptions of electronic cigarette risks and benefits: a concept mapping study
Authors: Liao Li-Ling , Chang Li-Chun , Lee Chia-Kuei , Lai I-Ju
Published: May 2024

The use of electronic cigarettes (e-cigarettes) is on the rise among young adults, with higher public acceptance than traditional tobacco. A study in Taiwan employed concept mapping to explore risk and benefit perceptions of e-cigarette use among college students. The study involved 100 college students from 11 Taiwanese universities, with 50 being e-cigarette users and 50 non-users. Data collection and analysis were done with the GroupWisdom™ platform. Participants engaged in brainstorming, rating and sorting their perceptions, which were analyzed using multidimensional scaling and hierarchical cluster analyses. The participants’ mean age was 19.24 years, and 55% were male. This process resulted in the identification of 10 clusters encompassing 64 statements, with 3 clusters focused on risk perceptions, 6 on benefit perceptions, and 1 dealing with e-cigarette regulations. Notably, risk perceptions were rated higher than benefit perceptions. Non-users held significantly higher risk perceptions and lower benefit perceptions across the nine clusters related to e-cigarette use. Concept mapping proved to be an effective tool for understanding college students’ perceptions. These findings can assist health educators in comprehending college students’ viewpoints on e-cigarette use and in developing targeted interventions. Additionally, exploring benefit perceptions may enhance students’ critical thinking skills regarding e-cigarette advertising.
How Social Workers Can Be Deployed to Assist with the Ongoing Opioid Crisis
Authors: Blanford Courtney , Rowell-Cunsolo Tawandra
Published: May 2024

The opioid epidemic has claimed more than 1 million lives in the United States over the past two decades. The persistent increase in deaths indicates that current strategies intended to decrease the negative consequences of opioid use are inadequate. Harm reduction strategies are designed to promote safer substance usage and reduce overdose mortality rates, yet the implementation of harm reduction programs is inhibited by community- and provider-level stigma against people who use opioids, coupled with limited understanding and insufficient education about harm reduction approaches. Despite ongoing research, engagement in opioid treatment programs remains a challenge, and the opioid crisis continues to disproportionately harm marginalized populations. This article describes how social workers are prepared to play a larger role in opioid use treatment because they are trained with the skill set and values necessary to facilitate access to harm reduction programs, promote engagement in substance use treatment, and create and advocate for interventions to address problematic substance use, especially in high-need communities.
The Dimension of the Set of ψ-Badly Approximable Points in All Ambient Dimensions: On a Question of Beresnevich and Velani
Authors: Koivusalo Henna , Levesley Jason , Ward Benjamin , Zhang Xintian
Published: May 2024

Let $\psi :{\mathbb{N}} \to [0,\infty )$, $\psi (q)=q^{-(1+\tau )}$ and let $\psi $-badly approximable points be those vectors in ${\mathbb{R}}^{d}$ that are $\psi $-well approximable, but not $c\psi $-well approximable for arbitrarily small constants $c>0$. We establish that the $\psi $-badly approximable points have the Hausdorff dimension of the $\psi $-well approximable points, the dimension taking the value $(d+1)/(\tau +1)$ familiar from theorems of Besicovitch and Jarník. The method of proof is an entirely new take on the Mass Transference Principle (MTP) by Beresnevich and Velani (Annals, 2006); namely, we use the colloquially named “delayed pruning” to construct a sufficiently large $\liminf $ set and combine this with ideas inspired by the proof of the MTP to find a large $\limsup $ subset of the $\liminf $ set. Our results are a generalisation of some $1$-dimensional results due to Bugeaud and Moreira (Acta Arith, 2011), but our method of proof is nothing alike.
Testing and Treatment Interventions in Community Settings Key to Controlling a Recent Human Immunodeficiency Virus Outbreak Among People Who Inject Drugs in Glasgow: A Modeling Study
Authors: Allen Lara I , Fraser Hannah , Stone Jack , McAuley Andrew , Trayner Kirsten M A , Metcalfe Rebecca , Peters S Erica , Hutchinson Sharon J , Vickerman Peter , Hickman Matthew
Published: May 2024

Background

A human immunodeficiency virus (HIV) outbreak was identified among people who inject drugs (PWID) in Glasgow in 2015, with >150 diagnoses by the end of 2019. The outbreak response involved scaling up HIV testing and improving HIV treatment initiation and retention.

Methods

We parameterized and calibrated a dynamic, deterministic model of HIV transmission among PWID in Glasgow to epidemiological data. We use this model to evaluate HIV testing and treatment interventions. We present results in terms of relative changes in HIV prevalence, incidence, and cases averted.

Results

If the improvements in both testing and treatment had not occurred, we predict that HIV prevalence would have reached 17.8% (95% credible interval [CrI], 14.1%–22.6%) by the beginning of 2020, compared to 5.9% (95% CrI, 4.7%–7.4%) with the improvements. If the improvements had been made on detection of the outbreak in 2015, we predict that peak incidence would have been 26.2% (95% CrI, 8.8%–49.3%) lower and 62.7% (95% CrI, 43.6%–76.6%) of the outbreak cases could have been averted. The outbreak could have been avoided if the improvements had already been in place.

Conclusions

Our modeling suggests that the HIV testing and treatment interventions successfully brought the HIV outbreak in Glasgow under control by the beginning of 2020.
Onnamide A suppresses the severe acute respiratory syndrome-coronavirus 2 infection without inhibiting 3-chymotrypsin-like cysteine protease
Authors: Hayashi Yasuhiro , Higa Nanami , Yoshida Tetsuro , Tyas Trianda Ayuning , Mori-Yasumoto Kanami , Yasumoto-Hirose Mina , Tani Hideki , Tanaka Junichi , Jomori Takahiro
Published: May 2024

Given the continuous emergence of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the development of new inhibitors is necessary to enhance clinical efficacy and increase the options for combination therapy for the coronavirus disease 2019. Because marine organisms have been a resource for the discovery of numerous bioactive molecules, we constructed an extract library of marine invertebrates collected from the Okinawa Islands. In this study, the extracts were used to identify antiviral molecules against SARS-CoV-2. Using a cytopathic effect (CPE) assay in VeroE6/TMPRSS2 cells, an extract from the marine sponge Theonella swinhoei was found to reduce virus-induced CPE. Eventually, onnamide A was identified as an antiviral compound in the extract using column chromatography and NMR analysis. Onnamide A inhibited several SARS-CoV-2 variant-induced CPEs in VeroE6/TMPRSS2 cells as well as virus production in the supernatant of infected cells. Moreover, this compound blocked the entry of SARS-CoV-2 pseudo-virions. Taken together, these results demonstrate that onnamide A suppresses SARS-CoV-2 infection, which may be partially related to entry inhibition, and is expected to be a candidate lead compound for the development of anti-SARS-CoV-2 drugs.