bluuebunny/crossref_metadata_2025 huggingface dataset:
Fairness- and Uncertainty-Aware Data Generation for Data-Driven Design Based on Active Learning
Authors: Xie Jiarui , Zhang Chonghui , Sun Lijun , Zhao Yaoyao Fiona
Published: January 2024

The design dataset is the backbone of data-driven design. Ideally, the dataset should be fairly distributed in both shape and property spaces to efficiently explore the underlying relationship. However, the classical experimental design focuses on shape diversity and thus yields biased exploration in the property space. Recently developed methods either conduct subset selection from a large dataset or employ assumptions with severe limitations. In this paper, fairness- and uncertainty-aware data generation (FairGen) is proposed to actively detect and generate missing properties starting from a small dataset. At each iteration, its coverage module computes the data coverage to guide the selection of the target properties. The uncertainty module ensures that the generative model can make certain and thus accurate shape predictions. Integrating the two modules, Bayesian optimization determines the target properties, which are thereafter fed into the generative model to predict the associated shapes. The new designs, whose properties are analyzed by simulation, are added to the design dataset. This constructs an active learning mechanism that iteratively samples new data to improve data representativeness and machine learning model performance. An S-slot design dataset case study was implemented to demonstrate the efficiency of FairGen in auxetic structural design. Compared with grid and randomized sampling, FairGen increased the coverage score at twice the speed and significantly expanded the sampled region in the property space. As a result, the generative models trained with FairGen-generated datasets showed consistent and significant reductions in mean absolute errors.
Probing an Easy-to-Deploy Multi-Agent Manufacturing System Based on Agent Computing Node: Architecture, Implementation, and Case Study
Authors: Wang Liping , Nie Qingwei , Zhang Zequn , Tang Dunbing , Liu Changchun
Published: January 2024

Due to the widespread adoption of personalized customization services, the application contexts within discrete manufacturing workshops have become increasingly intricate, necessitating the modern industry to evolve toward a more adaptable production trajectory. The pre-established production rules in a traditional centralized control manufacturing system present difficulties in accommodating dynamic situations. Although a multi-agent manufacturing system (MAMS) yields natural advantages in handling dynamic emergencies, the current research is limited to the computer simulation level and lacks integration with the underlying physical devices. In order to mitigate said challenges, the standardization modeling approach for the agent computing node (ACN) to facilitate the implementation of a readily deployable MAMS was proposed in the present study. Initially, adapters encompassing communication, decision, and control modules were developed within the industrial personnel computer-based computing node to accommodate the heterogeneous interface protocols of diverse machines. These adapters enable communication and interaction among machines while laying the computational foundation for the ACN. Accordingly, the models of the machine agent, the part agent, and the monitoring agent were constructed based on ACNs and could perceive the dynamic production information and support the enabling application. Subsequently, to guide ACNs in making scheduling decisions beneficial to global performance, an improved negotiation mechanism in MAMS was achieved in real-time. Finally, the proposed MAMS based on the ACN was deployed in an actual flexible machining workshop. Comparative experiments were implemented and, as exhibited from the experimental results, the proposed ACNs possessed the capabilities of achieving optimal global decision-making and facilitating straightforward deployment.
Bayesian-Optimized Riblet Surface Design for Turbulent Drag Reduction via Design-by-Morphing With Large Eddy Simulation
Authors: Lee Sangjoon , Moazam Sheikh Haris , Lim Dahyun D. , Gu Grace X. , Marcus Philip S.
Published: January 2024

A computational approach is presented for optimizing new riblet surface designs in turbulent channel flow for drag reduction, utilizing design-by-morphing (DbM), large Eddy simulation (LES), and Bayesian optimization (BO). The design space is generated using DbM to include a variety of novel riblet surface designs, which are then evaluated using LES to determine their drag-reducing capabilities. The riblet surface geometry and configuration are optimized for maximum drag reduction using the mixed-variable Bayesian optimization (MixMOBO) algorithm. A total of 125 optimization epochs are carried out, resulting in the identification of three optimal riblet surface designs that are comparable to or better than the reference drag reduction rate of 8%. The Bayesian-optimized designs commonly suggest riblet sizes of around 15 wall units, relatively large spacing compared to conventional designs, and spiky tips with notches for the riblets. Our overall optimization process is conducted within a reasonable physical time frame with up to 12-core parallel computing and can be practical for fluid engineering optimization problems that require high-fidelity computational design before materialization.
Multi-Objective Optimization Design of a Cobweb-Like Channel Heat Sink Using Particle Swarm Algorithm
Authors: Wei Hongmei , Yu Ruien
Published: January 2024

The cobweb-like microchannel heat sink is acknowledged for its exceptional heat transfer capabilities in comparison to other biomimetic microchannel heat sinks. The objective of this article is to improve the performance of the cobweb-like microchannel heat sink by optimizing its geometric structure parameters through a multi-objective approach. The Box–Behnken design method was utilized to conduct response surface analysis on the design variables, and the Pareto solution set was obtained by applying the multi-objective particle swarm optimization algorithm to the fitted functions of pressure and temperature. The TOPSIS method was used to select the most appropriate solution from the Pareto solution set. The performance of a microchannel heat sink was evaluated using the computational fluid dynamics (CFD) analysis. The optimized structure of the cobweb-like microchannel heat sink led to a decrease in the average temperature by 3 K and a reduction in pressure drop by 1514 Pa, as compared to the original design. This significant improvement in the overall performance highlights the importance of a well-designed channel structure in further enhancing the comprehensive performance of the microchannel heat sink.
Compressor Water Extraction
Authors: Farman Judith R. , Day Ivor J. , Dickens Tony M. J. , Taylor James V. , Hussain Zahid
Published: January 2024

The effect of putting a bleed slot behind the rotor or stator of a modern representative intermediate pressure compressor stage has been investigated using a purpose-built test rig. The first part of the paper goes over the construction and operation of a rig, which for the first time allows for accurate measurement of water extraction and rapid testing of a variety of bleed slot geometries. Using this test rig, it was found that the use of a bleed slot behind the rotor increases water extraction by up to 40 percentage points compared to placing it behind the stator. The overall extraction efficiency for the rotor exit was above 70% for all bleed rates considered from 0% to 30% and is relatively constant. Whilst rotor exit bleed might be advantageous for water extraction, further improvements in extraction efficiency are required for future engines with low fan speed and low blade solidity. The final part of the paper looks at the effect of a bleed lip protrusion to improve water extraction, as this can be retrofitted in engines. An extra 5 percentage points can be achieved by doing this without a penalty operability. This has been explained using 3D computational fluid dynamics by examining the flow separation topology.
Study on the Influence of Fan and Fan Cowl on Intake Air Parameters of Cooling Module
Authors: Zhang Zhenxing , Wang Dan , Guo Yue , Shen Lei , Wang Xiaodan
Published: January 2024

Due to the increase in heat load, the demand for heat dissipation of the cabin cooling module has increased. The fan arrangement and the design of the fan cowl can significantly affect the intake air parameters, thereby affecting the performance of the heat exchangers. In this paper, the whole vehicle model was set up and the effect of the fan installation distance, the fan cowl coverage ratio, and the radial extension of the fan cowl outlet was researched by numerical simulation. The results show that due to the relative position of the layout of the cooling module, the effect of the fan arrangement and the fan cowl design on the intake parameters of the radiator is greater than that of the intercooler. The improvement of the air velocity uniformity can reduce the intake air average temperature for better heat dissipation; a 2% improvement in air intake velocity uniformity can lead to a 6% reduction in air intake average temperature event at a low air mass flow. The extended installation distance of the fan or the increased closure degree of the fan cowl leads to more favorable intake parameters, thereby optimizing the cooling performance of the heat exchangers. Moreover, when the fan cowl coverage ratio reaches 0.9, the air intake average temperature increases by 5.6%, which means that the fan cowl coverage should not be too high. This study will provide useful reference information for the design of cooling modules in the cabin.
Multi-Physical Field Numerical Simulation of Electromagnetic Heating in Heavy Oil Reservoirs With Different Well Configurations
Authors: Chen Hong-Wei , Zhang Shan-Shan , Li Yang , Xu Chi , Qin Shu-Xing
Published: January 2024

Stable and efficient extraction of heavy oil is crucial for addressing the current shortage of crude oil resources. Electromagnetic (EM) heating effectively reduces oil viscosity and improves oil recovery rate by heating oil layers with EM radiation. However, the selection of well configurations for EM heating oil recovery has yet to be thoroughly studied. This article uses numerical simulation methods to study the effect of different well configurations on the oil recovery efficiency of EM heating heavy oil reservoirs. A complex EM heating model coupled with an EM temperature seepage field was established to simulate two different well configurations: vertical and horizontal wells. The results indicate that the horizontal well configuration is more efficient in heating heavy oil reservoirs in the same area than the vertical well configuration. Vertical heating wells facilitate the swift creation of a flow channel around the wellbore due to the direction of heavy oil flow coinciding with that of the well. However, the horizontal configuration takes longer for a flow channel to form. Despite this, the temperature distribution in the reservoir under the horizontal configuration is more uniform, and high temperatures do not accumulate around the heating wells. On the other hand, with a vertical configuration, the heat accumulates at the bottom of the well along with the flow of heavy oil. Increasing EM power and frequency can lead to a rise in reservoir temperature and facilitate the flow of heavy oil. However, it is important to note that beyond a certain point, the benefits of increased power and frequency become limited and may result in an excessively high temperature of heavy oil. These results can guide the selection of appropriate well configurations for EM heating in heavy oil reservoirs.
Experimental Investigation on the Thermal Performances of a New Design of Pulsating Heat Pipe With Two Condensers
Authors: Nikolaenko Yu. E. , Solomakha A. S. , Melnyk R. S. , Lipnitskyi L. V. , Kravets V. Yu. , Kozak D. V. , Pekur D. V.
Published: January 2024

In this paper, for the first time, a novel design of pulsating heat pipe (PHP) with one evaporator and two condensers located on both sides of the evaporator at an angle to the horizon was proposed, manufactured, and experimentally investigated for the purpose of use in cooling systems for electronic devices operating in a tilted position. The PHP body is made of a copper capillary tube with an inner diameter of 1.5 mm. The working fluid is methanol. The number of turns is 4. The heating zone dimensions are 60 mm × 36 mm, and the cooling zone dimensions are 200 mm × 35 mm. The РНР condensers were cooled by aluminum radiators blown by two fans with an air flowrate of 5.2 m3 h–1. The launch of the РНР began with a power of 30 W at all positive tilt angles and in a horizontal position. The dependences of the temperature in the heating and cooling zones and the PHP thermal resistance both on the power input (from 30 W to 200 W) and on the orientation in space (at tilt angles of 0 deg, 15 deg, 30 deg, 60 deg, 90 deg) were obtained. It is shown that when the evaporator is located below the condensers, the РНР works stably. Moreover, in the power range from 120 W to 200 W, the tilt angle practically does not affect the thermal resistance of the PHP. A comparison of the thermal resistance of the developed РНР with known РНРs filled with methanol showed the high efficiency of the developed РНР: at power input from 120 W to 200 W, the thermal resistance was from 0.2 °С W–1 to 0.18 °С W–1. The developed РНР design is promising for use in air cooling systems, for instance, of radar transmit/receive modules and high-power LED lighting systems.
Dynamic Behaviors of Delaminated Nanofilms Partly Bonded on Substrates With Sub-Nanoscale van der Waals Dynamic Boundaries
Authors: Dong Zhi-Qi , Hu Kai-Ming , Lin Hui-Yue , Deng Xin-Lu , Xin Yi-Hang , Meng Guang , Zhang Wen-Ming
Published: January 2024

Dynamic behaviors of delaminated nanofilms on substrates are universal and essential phenomena in nanoelectromechanical systems (NEMS). Van der Waals (vdWs) interactions play an important role in the dynamic behaviors of delaminated nanofilms on substrates due to the interaction distances at nanoscale or even sub-nanoscale in NEMS. Therefore, it is interesting yet challenging to reveal the effect of intermolecular vdWs interactions on dynamic behaviors of delaminated nanofilms on substrates. By considering sub-nanoscale dynamic boundary effects induced by intermolecular vdWs interactions, a parametric excitation nonlinear vibration model for dynamic behaviors of delaminated nanofilms partly bonded on substrates is established. Effects of sub-nanoscale vdWs dynamic boundaries on transient and steady-state responses of dynamically delaminated nanofilms on substrates are analyzed. The sub-nanoscale vdWs dynamic boundaries lead the dynamic responses of delaminated-nanofilm/substrate systems very sensitive to initial conditions. The bending and shifting frequency response results demonstrated that the system nonlinearities can be greatly amplified by the sub-nanoscale vdWs dynamic boundary effect. Moreover, the spontaneous symmetry breaking and violent interfacial tearing/healing phenomena can be also triggered in the systems. Based on spontaneous symmetry breaking, a trans-scale relationship between nanofilm equilibrium positions and intermolecular vdWs interactions is established, which can provide a promising route for trans-scale measurements of molecular scale interfacial interactions. The work can also be helpful for the dynamic design of resonant NEMS devices based on nanofilm/substrate systems.
Enhancing minority carrier lifetime in Ge: Insights from HF and HCl cleaning procedures
Authors: Chapotot Alexandre , Chrétien Jérémie , Fesiienko Oleh , Pargon Erwine , Cho Jinyoun , Dessein Kristof , Boucherif Abderraouf , Hamon Gwenaëlle , Darnon Maxime
Published: January 2024

Efficiently passivating germanium (Ge) surfaces is crucial to reduce the unwanted recombination current in high-performance devices. Chemical surface cleaning is critical to remove surface contaminants and Ge oxides, ensuring effective surface passivation after dielectric deposition. However, Ge oxides can rapidly regrow upon air exposure. To understand the surface evolution after wet cleaning, we present a comprehensive study comparing HF and HCl deoxidation steps on p-type Ge surfaces and monitor the surface as a function of air exposure time. Distinct oxide regrowth dynamics are observed: HF-treated samples exhibit swift regrowth of all Ge oxide states, whereas HCl-treated Ge surfaces exhibit a lower concentration of low degrees of oxidation and slower or no regrowth of high oxide states even after 110 min of air exposure. In addition, the presence of Ge–Cl bonds induces different oxidation dynamics compared to the Ge–OH bonds resulting from HF cleaning. This leads to varying surface electronic band structures, with HF-treated Ge exhibiting a strong positive band bending (+0.20 eV). Conversely, HCl-treated samples display a lower band curvature (+0.07 eV), mostly due to the presence of Ge–Cl bonds on the Ge surface. During air exposure, the increased GeOx coverage significantly reduces the band bending after HF, while a constant band bending is observed after HCl. Finally, these factors induce a reduction in the surface recombination velocity after wet etching. Combining both chemical and field-induced passivation, HF-treated Ge without rinsing exceeds 800 μs.
Active learning with moment tensor potentials to predict material properties: Ti0.5Al0.5N at elevated temperature
Authors: Bock F. , Tasnádi F. , Abrikosov I. A.
Published: January 2024

Transition metal nitride alloys possess exceptional properties, making them suitable for cutting applications due to their inherent hardness or as protective coatings due to corrosion resistance. However, the computational demands associated with predicting these properties using ab initio methods can often be prohibitively high at the conditions of their operation at cutting tools, that is, at high temperatures and stresses. Machine learning approaches have been introduced into the field of materials modeling to address the challenge. In this paper, we present an active learning workflow to model the properties of our benchmark alloy system cubic B1 Ti0.5Al0.5N at temperatures up to 1500 K. With a minimal requirement of prior knowledge about the alloy system for our workflow, we train a moment tensor potential (MTP) to accurately model the material’s behavior over the entire temperature range and extract elastic and vibrational properties. The outstanding accuracy of MTPs with relatively little training data demonstrates that the presented approach is highly efficient and requires about two orders of magnitude less computational resources than state-of-the-art ab initio molecular dynamics.
Finite-frequency modeling of regional tropospheric infrasound using realistic atmospheres and terrain
Authors: Bishop Jordan W. , Blom Philip , Fee David
Published: January 2024

Infrasonic waves have been observed to propagate to regional (greater than 15 km) distances through the troposphere. Infrasound propagation in the geometric acoustics approximation has shown that realistic terrain can scatter acoustic energy from tropospheric ducts; however, ray methods cannot intrinsically capture finite-frequency behavior such as diffraction. A two-dimensional finite-difference time-domain (FDTD) method has been developed to solve linearized equations for infrasound propagation with realistic terrain. Acoustic wave propagation over 100 km with both flat terrain and a Gaussian hill was first simulated in order to compare finite-frequency propagation with ray predictions. The effects of realistic terrain and atmospheres on infrasound signals from a 2012 surface explosion at the Utah Testing and Training Range are then investigated. Propagation through the troposphere is suggested by array processing results, but eigenrays are not predicted due to weak to nonexistent ducting conditions. FDTD modeling suggests that the inclusion of terrain and finite frequency effects helps explain much of the observed signal in a realistic scenario. These results suggest that geometric acoustics may underestimate propagation through the troposphere, and that recorded waveforms at regional distances may be noticeably affected by terrain.
Adaptive sparse estimation of nonlinear chirp signals using Laplace priors
Authors: Tu Xiaotong , Liang Hao , Jakobsson Andreas , Huang Yue , Ding Xinghao
Published: January 2024

The identification of nonlinear chirp signals has attracted notable attention in the recent literature, including estimators such as the variational mode decomposition and the nonlinear chirp mode estimator. However, most presented methods fail to process signals with close frequency intervals or depend on user-determined parameters that are often non-trivial to select optimally. In this work, we propose a fully adaptive method, termed the adaptive nonlinear chirp mode estimation. The method decomposes a combined nonlinear chirp signal into its principal modes, accurately representing each mode's time-frequency representation simultaneously. Exploiting the sparsity of the instantaneous amplitudes, the proposed method can produce estimates that are smooth in the sense of being piecewise linear. Furthermore, we analyze the decomposition problem from a Bayesian perspective, using hierarchical Laplace priors to form an efficient implementation, allowing for a fully automatic parameter selection. Numerical simulations and experimental data analysis show the effectiveness and advantages of the proposed method. Notably, the algorithm is found to yield reliable estimates even when encountering signals with crossed modes. The method's practical potential is illustrated on a whale whistle signal.
Lower-Extremity Energetic Distribution During Rate-Controlled Ballet Jumps (Sautés) in Healthy Dancers
Authors: Yamaguchi Amanda C. , Trejo Lindsey H. , Shih Hai-Jung Steffi , Ortiz-Weissberg David , Kulig Kornelia
Published: January 2024

Dancers frequently perform jumps in the context of a prolonged, continuous dance piece. The purpose of this study is to explore the lower-extremity energetics in healthy dancers performing repetitive dance jumps (sautés) before and after typical dance-specific choreography. Lower-extremity kinetic data were collected from 14 healthy female dancers during a series of sautés performed before and after 3 minutes of dance. Percent contributions of the lower-extremity joints to the whole-limb mechanical energy expenditure during ground contact were calculated. The jumps performed at the beginning were compared with the jumps at the end of the dance choreography. Dancers maintained the jump rate and consistent whole-limb mechanical energy expenditure between the jump series. As expected, for both jump series, the sautés had greater relative energetic contribution from the ankle and knee as compared with lesser contribution from the hip and toe. However, we observed lesser contribution from the knee and greater contribution from the hip after a 3-minute dance. After performing typical dance choreography, the dancers demonstrated a distal to proximal redistribution of individual joints’ contribution to whole-limb mechanical energy expenditure.
Personalization Characteristics and Evaluation of Gamified Exercise for Middle-Aged and Older People: A Scoping Review
Authors: Ren Lisha , Yan Jie , Zhu Zhehao , Du Murui
Published: January 2024

Many studies have shown that personalized exergames have a positive effect on promoting regular and proper exercise. However, there is no consensus on the design characteristics and evaluation of exergames. This systematic review of published research literature aimed to explore the general characteristics, personalization characteristics, and evaluation of personalized exergames for middle-aged and older people. We screened published studies in the Web of Science, Scopus, PubMed, ACM, and IEEE Xplore databases, extracted data, and performed a thematic analysis according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist. Three main themes and nine subthemes were generated from 24 included papers. Moreover, a personalization model (FACTS) and evaluation system (PMSS) of exergames were developed. Personalized exergames had potential positive effects on motivating middle-aged and older people to exercise and improve their health, particularly physical, mental, and social health. However, more fine-grained studies on personalized exergames are necessary in the future.
Effect of Floss Band on Anaerobic Exercise and Muscle Tissue Oxygenation
Authors: Marko David , Vymyslický Patrik , Miřátský Petr , Bahenský Petr , Malý Tomáš , Vobr Radek , Krajcigr Miroslav
Published: January 2024

Context: Flossing is still a relatively new technique that has yielded varied results in the research literature; therefore, it requires further investigation. Previous research has shown that thigh tissue flossing might improve performance in countermovement jump, sprint time, maximum voluntary contraction, and rate of force development. Design: The present study aims to investigate the effect of the floss band on performance during the Wingate test (30-WAT), muscle oxygen saturation (SpO2), and total hemoglobin in vastus lateralis. Methods: Twenty-two students of physical education and sport (11 men and 11 women) were randomly selected to complete either the Wingate test with the application of a floss band in warm-up or the Wingate test without the use of a floss band, followed by the alternative 24 hours apart. Results: Throughout the testing, the floss band did not affect performance values during the Wingate test (relative peak power, relative average power, and fatigue index). However, there was a medium to large effect difference during 1 minute prior to 30-WAT (PRE), during the 30-WAT, and 10-minute recovery (REC) in values of SpO2 and total hemoglobin. Use of floss band displayed a higher SpO2 during PRE, 30-WAT, and REC by ∼13.55%, d < 2; ∼19.06%, d = 0.89; and ∼8.55%, d = 0.59, respectively. Conclusion: Collectively, these findings indicate that the application of thigh flossing during warm-up has no effect on 30-WAT performance; however, SpO2 was significantly increased in all stages of testing. This could lead to potential improvement in repeated anaerobic exercise due to increased blood flow. Increased muscle oxygen saturation can also lead to improved tissue healing as oxygen supply is essential for tissue repair, wound healing, and pain management.
Convergence in carnivorous pitcher plants reveals a mechanism for composite trait evolution
Authors: Chomicki Guillaume , Burin Gustavo , Busta Lucas , Gozdzik Jedrzej , Jetter Reinhard , Mortimer Beth , Bauer Ulrike
Published: January 2024

Composite traits involve multiple components that, only when combined, gain a new synergistic function. Thus, how they evolve remains a puzzle. We combined field experiments, microscopy, chemical analyses, and laser Doppler vibrometry with comparative phylogenetic analyses to show that two carnivorous
Nepenthes
pitcher plant species independently evolved similar adaptations in three distinct traits to acquire a new, composite trapping mechanism. Comparative analyses suggest that this new trait arose convergently through “spontaneous coincidence” of the required trait combination, rather than directional selection in the component traits. Our results indicate a plausible mechanism for composite trait evolution and highlight the importance of stochastic phenotypic variation as a facilitator of evolutionary novelty.
Direct propylene epoxidation via water activation over Pd-Pt electrocatalysts
Authors: Chung Minju , Maalouf Joseph H. , Adams Jason S. , Jiang Chenyu , Román-Leshkov Yuriy , Manthiram Karthish
Published: January 2024

Direct electrochemical propylene epoxidation by means of water-oxidation intermediates presents a sustainable alternative to existing routes that involve hazardous chlorine or peroxide reagents. We report an oxidized palladium-platinum alloy catalyst (PdPtO

x

/C), which reaches a Faradaic efficiency of 66 ± 5% toward propylene epoxidation at 50 milliamperes per square centimeter at ambient temperature and pressure. Embedding platinum into the palladium oxide crystal structure stabilized oxidized platinum species, resulting in improved catalyst performance. The reaction kinetics suggest that epoxidation on PdPtO

x

/C proceeds through electrophilic attack by metal-bound peroxo intermediates. This work demonstrates an effective strategy for selective electrochemical oxygen-atom transfer from water, without mediators, for diverse oxygenation reactions.
The genetic basis of a recent transition to live-bearing in marine snails
Authors: Stankowski Sean , Zagrodzka Zuzanna B. , Garlovsky Martin D. , Pal Arka , Shipilina Daria , Castillo Diego Garcia , Lifchitz Hila , Le Moan Alan , Leder Erica , Reeve James , Johannesson Kerstin , Westram Anja M. , Butlin Roger K.
Published: January 2024

Key innovations are fundamental to biological diversification, but their genetic basis is poorly understood. A recent transition from egg-laying to live-bearing in marine snails (
Littorina
spp.) provides the opportunity to study the genetic architecture of an innovation that has evolved repeatedly across animals. Individuals do not cluster by reproductive mode in a genome-wide phylogeny, but local genealogical analysis revealed numerous small genomic regions where all live-bearers carry the same core haplotype. Candidate regions show evidence for live-bearer–specific positive selection and are enriched for genes that are differentially expressed between egg-laying and live-bearing reproductive systems. Ages of selective sweeps suggest that live-bearer–specific alleles accumulated over more than 200,000 generations. Our results suggest that new functions evolve through the recruitment of many alleles rather than in a single evolutionary step.
Cobalt-catalyzed synthesis of amides from alkenes and amines promoted by light
Authors: Faculak Mason S. , Veatch Alexander M. , Alexanian Erik J.
Published: January 2024

Catalytic methods to couple alkene and amine feedstocks are valuable in synthetic chemistry. The direct carbonylative coupling of alkenes and amines holds promise as a perfectly atom-economical approach to amide synthesis, but general methods remain underdeveloped. Herein, we report an alkene hydroaminocarbonylation catalyzed by unmodified, inexpensive cobalt carbonyl under mild conditions and low pressure promoted by light. Silane addition after the reaction enables sequential cobalt-catalyzed amide reduction, constituting a formal alkene hydroaminomethylation. These methods exhibit exceptional scope across both alkene and amine components with high chemo- and regioselectivity and proceed efficiently even in the absence of solvent. The formation of a hydridocobalt through photodissociation of a carbonyl ligand is proposed to enable catalytic activity under mild conditions, which addresses a long-standing challenge in catalysis.
A stable rhodium-coordinated carbene with a σ
0
π
2
electronic configuration
Authors: Hu Chaopeng , Wang Xin-Feng , Li Jiancheng , Chang Xiao-Yong , Liu Liu Leo
Published: January 2024

Isolable singlet carbenes have universally adopted a σ
2
π
0
electronic state, making them σ-donors and π-acceptors. We present a rhodium-coordinated, cationic cyclic diphosphinocarbene with a σ
0
π
2
ground state configuration. Nuclear magnetic resonance spectroscopy studies show a carbene carbon chemical shift below −30.0 parts per million. X-ray crystallography reveals a planar RhP
2
C configuration. Quantum chemical calculations rationalize how σ-electron delocalization/donation and π-electron negative hyperconjugation together stabilize the formally vacant σ orbital and the filled π orbital at the carbene center. In contrast to traditional carbene counterparts this carbene can undergo synthetic transformations with both a Lewis base and a silver salt, producing a Lewis acid/base adduct and a silver π-complex, respectively. Exhibiting ambiphilic reactivity, it can also form a ketenimine through reaction with an isocyanide.
Data-driven hope for the planet
Not the End of the World: How We Can Be the First Generation to Build a Sustainable Planet
Hannah Ritchie
Little, Brown Spark, 2024. 352 pp.
Authors: Ellis Erle C.
Published: January 2024

A data scientist offers an optimistic reality check for the Anthropocene
Evolutionary paths to new phenotypes
Authors: Elmer Kathryn R.
Published: January 2024

Ecological model systems inform on innovative traits in plants and animals
Creating the “plumber’s nightmare”
Authors: Nedoma Alisyn J.
Published: January 2024

Chemically modifying polymer ends enables tailoring of nanostructured materials
In Science Journals
Authors: Szuromi Phil , Scanlon Seth Thomas , Yeston Jake S. , Stajic Jelena , Norton Melissa L. , Fogg Christiana N. , Funk Michael A. , Stern Peter , Lavine Marc S. , Lopez Bianca , Simonti Corinne , VanHook Annalisa M.
Published: January 2024

Highlights from the
Science
family of journals
Laid to waste
Authors: Stone Richard
Published: January 2024

Ukrainian scientists are tallying the grave environmental consequences of the Kakhovka Dam disaster
Japan tries, again, to boost global ranking of its universities
Authors: Normile Dennis
Published: January 2024

But researchers fear a plan to increase outside oversight of six top schools could create new problems
Peru moves to crack down on fraud in research publishing
Authors: Orfila María de los Ángeles
Published: January 2024

Two new laws would make it easier to punish scientists who buy authorship and commit other misdeeds
In Other Journals
Authors: Osborne Ian S. , Ross Sarah H. , Lopez Bianca , Jiang Di , Ash Caroline , Stajic Jelena , Smith H. Jesse
Published: January 2024

Editors’ selections from the current scientific literature
Infection biology of
Salmonella enterica
Authors: Han Jing , Aljahdali Nesreen , Zhao Shaohua , Tang Hailin , Harbottle Heather , Hoffmann Maria , Frye Jonathan G. , Foley Steven L.
Published: January 2024

Salmonella enterica
is the leading cause of bacterial foodborne illness in the USA, with an estimated 95% of salmonellosis cases due to the consumption of contaminated food products.
Salmonella
can cause several different disease syndromes, with the most common being gastroenteritis, followed by bacteremia and typhoid fever. Among the over 2,600 currently identified serotypes/serovars, some are mostly host-restricted and host-adapted, while the majority of serotypes can infect a broader range of host species and are associated with causing both livestock and human disease.
Salmonella
serotypes and strains within serovars can vary considerably in the severity of disease that may result from infection, with some serovars that are more highly associated with invasive disease in humans, while others predominantly cause mild gastroenteritis. These observed clinical differences may be caused by the genetic make-up and diversity of the serovars.
Salmonella
virulence systems are very complex containing several virulence-associated genes with different functions that contribute to its pathogenicity. The different clinical syndromes are associated with unique groups of virulence genes, and strains often differ in the array of virulence traits they display. On the chromosome, virulence genes are often clustered in regions known as
Salmonella
pathogenicity islands (SPIs), which are scattered throughout different
Salmonella
genomes and encode factors essential for adhesion, invasion, survival, and replication within the host. Plasmids can also carry various genes that contribute to
Salmonella
pathogenicity. For example, strains from several serovars associated with significant human disease, including Choleraesuis, Dublin, Enteritidis, Newport, and Typhimurium, can carry virulence plasmids with genes contributing to attachment, immune system evasion, and other roles. The goal of this comprehensive review is to provide key information on the
Salmonella
virulence, including the contributions of genes encoded in SPIs and plasmids during
Salmonella
pathogenesis.
Brucella
targets the host ubiquitin-specific protease,
Usp8
, through the effector protein, TcpB, for facilitating infection of macrophages
Authors: Joshi Kiranmai , Mazumdar Varadendra , Nandi Binita Roy , Radhakrishnan Girish K.
Published: January 2024

Brucella
species are Gram-negative intracellular bacterial pathogens that cause the worldwide zoonotic disease brucellosis.
Brucella
can infect many mammals, including humans and domestic and wild animals.
Brucella
manipulates various host cellular processes to invade and multiply in professional and non-professional phagocytic cells. However, the host targets and their modulation by
Brucella
to facilitate the infection process remain obscure. Here, we report that the host ubiquitin-specific protease, USP8, negatively regulates the invasion of
Brucella
into macrophages through the plasma membrane receptor, CXCR4. Upon silencing or chemical inhibition of USP8, the membrane localization of the CXCR4 receptor was enriched, which augmented the invasion of
Brucella
into macrophages. Activation of USP8 through chemical inhibition of 14-3-3 protein affected the invasion of
Brucella
into macrophages.
Brucella
suppressed the expression of
Usp8
at its early stage of infection in the infected macrophages. Furthermore, we found that only live
Brucella
could negatively regulate the expression of
Usp8
, suggesting the role of secreted effector protein of
Brucella
in modulating the gene expression. Subsequent studies revealed that the
Brucella
effector protein, TIR-domain containing protein from
Brucella
, TcpB, plays a significant role in downregulating the expression of
Usp8
by targeting the cyclic-AMP response element-binding protein pathway. Treatment of mice with USP8 inhibitor resulted in enhanced survival of
B. melitensis,
whereas mice treated with CXCR4 or 14-3-3 antagonists showed a diminished bacterial load. Our experimental data demonstrate a novel role of
Usp8
in the host defense against microbial intrusion. The present study provides insights into the microbial subversion of host defenses, and this information may ultimately help to develop novel therapeutic interventions for infectious diseases.
Supplemental Material: Crucial role of water-present melting in metagranite: Implications for the instigation of crustal-scale shear zones
Authors: Vanardois Jonas , al. et
Published: January 2024

Methodology and parameters used for phase diagram modeling, including Figures S1–S3. 
Overlap reduction function for pulsar timing arrays in an expanding Universe
Authors: Zhu Qing-Hua
Published: January 2024

Since it was confirmed two decades ago that the expansion of the Universe is accelerating, it would be of theoretical interests to figure out what is the influence from cosmological constant on detection of stochastic gravitational wave background. This paper studies the overlap reduction functions in de-Sitter space-time for a pair of one-way tracking gravitational wave detectors. It is shown to be non-trivial in an expanding Universe, because the propagation of light along line of sight also has effect on the response of GW detectors. It is found that the expansion of the Universe can enhance the value of magnitude of the overlap reduction functions, when the detector pairs are close to each other. For nanohertz gravitational waves, this effect can dominate the values of overlap reduction functions when the galactic pulsar pairs are separated by milliarcsecond.
Logistics Service Openness Strategy of Online Platforms with Vertical Differentiation and Endogenous Service Level
Authors: Hu Yihong , Duan Yongrui , Qu Shengnan , Huo Jiazhen
Published: January 2024

This paper explores the strategic motivation for a platform to open its superior logistics service to a third-party seller with an endogenous service level. We consider a Stackelberg game between the platform and the seller who sells products to consumers who perceive the platform’s product as having a higher value than the seller’s product. We characterize the equilibrium results in two schemes regarding opening or not opening the service and present conditions for the platform to open the service and the seller to accept the service. In equilibrium, the platform’s logistics service remains at the same level before and after opening. Particularly, we demonstrate that the motivation for the platform to open the service is not simply collecting extra revenue from the service but can be understood from mitigating price competition and securing its demand and price. We find that the platform is always willing to open the logistics system because it provides the platform an additional tool to manipulate the seller’s pricing behavior and therefore improves its own profit. With a high commission rate, the platform is even willing to subsidize the seller for using the logistics service. A Pareto improvement can be realized for two firms when consumers are highly sensitive to the service level. Consumers are worse off after service opening in most cases. Our analysis offers insights into the incentives of one retailer providing high-quality service for its rival when retailers differentiate in price and service.
Latino Opinion and Action in the Struggle for America's Political Future
Authors: Pérez Efrén , Cobian Jessica
Published: January 2024

Nearly 20 years have passed since this journal's last review of Latino politics. Today, American politics have shifted dramatically, even alarmingly, with Latinos absorbing and contributing to many of these changes. Yet American politics research still overwhelmingly privileges non-Hispanic Whites and their political opinions and behavior. We argue that this marginalization of Latino politics research has even fewer excuses in this era when data, methodologies, and other resources have expanded, making theory-based, empirically grounded research on Latino politics more feasible. We also argue that to better grasp what happens in contemporary politics today and tomorrow, a deeper understanding of Latinos’ political psychology is indispensable because they are a highly diverse, minoritized group whose members are acutely sensitive to structural, temporal, and situational pressures. Finally, in an overwhelmingly quantitative, empirically oriented field, we urge Latino politics scholars to more earnestly consider the normative implications of research on this growing pan-ethnic population.
The complete guide to hosting a guest speaker
Authors: Seals Douglas R.
Published: January 2024

This Personal View on Training and Mentoring provides a comprehensive guide to successfully hosting a guest speaker that should help inform and advance the professional development of students, postdoctoral fellows, and other early-stage investigators.
Impaired cardiopulmonary baroreflex function and altered cardiovascular responses to hypovolemia in patients with heart failure with preserved ejection fraction
Authors: Alpenglow Jeremy K. , Bunsawat Kanokwan , Francisco Michael A. , Craig Jesse C. , Iacovelli Jarred J. , Ryan John J. , Wray D. Walter
Published: January 2024

Data from the current study demonstrate diminished cardiovascular responsiveness during hypovolemia induced by incremental lower-body negative pressure in patients with heart failure with preserved ejection fraction (HFpEF). These diminished responses imply impaired cardiopulmonary baroreflex function and altered autonomic cardiovascular regulation which may represent an important aspect of HFpEF pathophysiology.
Role of TNF-α in the Pathogenesis of Migraine
Authors: Sudershan Amrit , Sudershan Srishty , Sharma Isha , Kumar Hardeep , Panjaliya Rakesh K. , Kumar Parvinder
Published: January 2024

Background. Neurogenic neuroinflammation has a wide role in migraine pathogenesis including the transition from episodic migraine to chronic one. The seed molecule of neurogenic neuroinflammation, i.e., the TNF-α proinflammatory molecule, has gathered a lot of attention. This pleiotropic cytokine is a classical component of inflammatory soup, secreted by the microglial cell, and promotes a wide range of inflammatory reactions. Aim. In this review, we aimed to provide a culminating and comprehending glimpse into the TNF-α in association with the migraine. Method. A systematic literature survey method with a mixture of keywords was utilized to grasp the different elements that represent the association between TNF-α and migraine. Discussion. Highlighted the probable involvement of the TNF-α with migraine, the complexity of the matter such as activation of NF-KB signaling cascade, autoactivation, sensitization, and increased likelihood of transition cannot be neglected. Being TNF-α as a core node, it becomes the factor for linking diseases such as chronic inflammatory disorders, including COVID-19, and also interaction with other genes to develop severe conditions. Conclusion. To this end, TNF-α plays a critical role in chronification, and inhibiting its signaling would likely be a crucial strategy for migraine therapy.
Channel-Boosted and Transfer Learning Convolutional Neural Network-Based Osteoporosis Detection from CT Scan, Dual X-Ray, and X-Ray Images
Authors: Dhanagopal R. , Menaka R. , Suresh Kumar R. , Vasanth Raj P. T. , Debrah E. L. , Pradeep K.
Published: January 2024

Osteoporosis is a word used to describe a condition in which bone density has been diminished as a result of inadequate bone tissue development to counteract the elimination of old bone tissue. Osteoporosis diagnosis is made possible by the use of medical imaging technologies such as CT scans, dual X-ray, and X-ray images. In practice, there are various osteoporosis diagnostic methods that may be performed with a single imaging modality to aid in the diagnosis of the disease. The proposed study is to develop a framework, that is, to aid in the diagnosis of osteoporosis which agrees to all of these CT scans, X-ray, and dual X-ray imaging modalities. The framework will be implemented in the near future. The proposed work, CBTCNNOD, is the integration of 3 functional modules. The functional modules are a bilinear filter, grey-level zone length matrix, and CB-CNN. It is constructed in a manner that can provide crisp osteoporosis diagnostic reports based on the images that are fed into the system. All 3 modules work together to improve the performance of the proposed approach, CBTCNNOD, in terms of accuracy by 10.38%, 10.16%, 7.86%, and 14.32%; precision by 11.09%, 9.08%, 10.01%, and 16.51%; sensitivity by 9.77%, 10.74%, 6.20%, and 12.78%; and specificity by 11.01%, 9.52%, 9.5%, and 15.84%, while requiring less processing time of 33.52%, 17.79%, 23.34%, and 10.86%, when compared to the existing techniques of RCETA, BMCOFA, BACBCT, and XSFCV, respectively.
Extraction of Feature Information from Point Cloud of Large Volume Steel Truss Members
Authors: Liang Dong , Zhang Zeyu , Guo Bo , Wang Bo , Wang Xiongjue
Published: January 2024

In order to address the issues pertaining to the subjective nature and limited precision associated with selecting feature points in the point cloud of a large steel truss structure, this study proposes a batch automatic extraction approach for identifying key feature information, including boundaries, corner points, and bolt holes of large steel truss components. This method relies on the nested application of established processing algorithms such as Euclidean clusters, regional growth clusters, and random sampling consensus. In addition, a novel approach is suggested for validating the precision of feature information extraction through the utilization of standard theoretical models. The results of the experimental and large‐scale lower chord tests demonstrate that our approach is not dependent on specialized software, exhibits excellent efficiency, and possesses an acceptable degree of automation. The findings of this study can provide accurate data support for reverse modeling, virtual trial assembly, and dimensional inspection of steel truss components.