bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen-doped carbon dots: a novel biosensing platform for selective norfloxacin detection and bioimaging
Authors: Sivaselvam S. , Anjana R. S. , Dhujana N. S. , Victor Marina , Jayasree Ramapurath S.
Published: July 2024

Nitrogen-based quantum dots (N-Ch-CQDs) serve as an efficient biosensor platform with bioimaging capabilities to combat antibiotic resistance resulting from norfloxacin residues, which pose a significant public health threat due to their incomplete metabolism and non-biodegradable nature.
Robust spin-valley coupling in hexagonal monolayers of Tl-based monochalcogenides
Authors: Sheng Kang , Wang Zhi-Yong
Published: July 2024

Monolayers of Tl-based monochalcogenides are theoretically identified as an ideal platform for the integration of spintronics and valleytronics.
Tunable valence state and scintillation performance of dense Ce3+-doped borosilicate glasses prepared in ambient atmosphere
Authors: Sun Xin-Yuan , Hua Zhehao , Chen Xi , Wen Yufeng , Qian Sen , Cai Hua , Chen Danping , Han Jifeng , Lin Richeng , Liu Shan , Ren Jing , Tang Gao , Yin Shenghua , Zhang Minghui , Zheng Lirong
Published: July 2024

Tunable valence state and scintillation properties from Ce-doped gadolinium aluminoborosilicate glass scintillators for high-energy physics applications.
Implementing Ecological Momentary Assessment in Audiological Research: Opportunities and Challenges
Authors: Schinkel-Bielefeld Nadja , Burke Louise , Holube Inga , Iankilevitch Maria , Jenstad Lorienne M. , Lelic Dina , Naylor Graham , Singh Gurjit , Smeds Karolina , von Gablenz Petra , Wolters Florian , Wu Yu-Hsiang
Published: July 2024

Ecological momentary assessment (EMA) is a way to evaluate experiences in everyday life. It is a powerful research tool but can be complex and challenging for beginners. Application of EMA in audiological research brings with it opportunities and challenges that differ from other research disciplines. This tutorial discusses important considerations when conducting EMA studies in hearing care. While more research is needed to develop specific guidelines for the various potential applications of EMA in hearing research, we hope this article can alert hearing researchers new to EMA to pitfalls when using EMA and help strengthen their study design. The current article elaborates study design details, such as choice of participants, representativeness of the study period for participants' lives, and balancing participant burden with data requirements. Mobile devices and sensors to collect objective data on the acoustic situation are reviewed alongside different possibilities for EMA setups ranging from online questionnaires paired with a timer to proprietary apps that also have access to parameters of a hearing device. In addition to considerations for survey design, a list of questionnaire items from previous studies is provided. For each item, an example and a list of references are given. EMA typically provides data sets that are rich but also challenging in that they are noisy, and there is often unequal amount of data between participants. After recommendations on how to check the data for compliance, reactivity, and careless responses, methods for statistical analysis on the individual level and on the group level are discussed including special methods for direct comparison of hearing device programs.
Intelligibility of Natively and Nonnatively Produced English Speech Presented in Noise to a Large Cohort of United States Service Members
Authors: Bieber Rebecca E. , Makashay Matthew J. , Sheffield Benjamin M. , Brungart Douglas S.
Published: July 2024

Purpose:

A corpus of English matrix sentences produced by 60 native and nonnative speakers of English was developed as part of a multinational coalition task group. This corpus was tested on a large cohort of U.S. Service members in order to examine the effects of talker nativeness, listener nativeness, masker type, and hearing sensitivity on speech recognition performance in this population.

Method:

A total of 1,939 U.S. Service members (ages 18–68 years) completed this closed-set listening task, including 430 women and 110 nonnative English speakers. Stimuli were produced by native and nonnative speakers of English and were presented in speech-shaped noise and multitalker babble. Keyword recognition accuracy and response times were analyzed.

Results:

General(ized) linear mixed-effects regression models found that, on the whole, speech recognition performance was lower for listeners who identified as nonnative speakers of English and when listening to speech produced by nonnative speakers of English. Talker and listener effects were more pronounced when listening in a babble masker than in a speech-shaped noise masker. Response times varied as a function of recognition score, with longest response times found for intermediate levels of performance.

Conclusions:

This study found additive effects of talker and listener nonnativeness when listening to speech in background noise. These effects were present in both accuracy and response time measures. No multiplicative effects of talker and listener language background were found. There was little evidence of a negative interaction between talker nonnativeness and hearing impairment, suggesting that these factors may have redundant effects on speech recognition.

Supplemental Material:

https://doi.org/10.23641/asha.26060191
An RC snubber design method to achieve optimized switching noise‐loss trade‐off of cascode GaN HEMTs
Authors: Xue Peng , Hoene Eckart , Davari Pooya
Published: July 2024

The cascode gallium nitride high electron mobility transistors (GaN HEMTs) are very vulnerable to self‐sustained turn‐off oscillation due to their cascode configuration. This paper presents a design approach for the RC snubber of cascode GaN HEMTs to achieve the optimized noise‐loss trade‐off. At first, an analytical model is proposed to describe the instability of cascode GaN HEMTs‐based test circuits utilizing RC snubber. Based on the model, an analytical approach is proposed to achieve two optimum RC snubber designs S1 and S2. The design S1 can satisfactorily dampen the oscillation with minimum switching losses. The design S2 achieves maximum effective damping on the oscillation at a minimized cost of additional power losses. In the end, the accuracy of the proposed model is validated by the double‐pulse test and good agreement is obtained.
RETRACTED: Interoperable square‐circular coupled coils for wireless electric vehicle battery charging system with different misalignments
Authors: Banothu Charan Singh , Gorantla Srinivasa Rao , Attuluri Rakada Vijay Babu , Evuri Geetha Reddy
Published: July 2024

A substantial interest in inductive power transfer (IPT) is due to its straight forwardness and dependability in charging electric vehicle (EV) batteries for researchers. The mutual inductance (MI) plays a critical role in the IPT system as it enables efficient power transfer. Therefore, it is imperative to examine the MI between the two coils that are connected through inductive coupling. This work investigates the MI and efficiency of connected coils in interoperable conditions. The transmitter coil is arranged in the shape of a square (TxS), whereas the reception coil is arranged in the shape of a circle (RxC). A concise and user‐friendly collection of design guidelines for S‐S compensated resonant inductive power transfer (SS‐RIPT) systems the design concepts efficiently mitigate the possibility of systematically and unambiguously setting the specifications for a given load profile. A 3.6‐kW setup has been constructed and validated by finite element analysis and experimental testing, following the design specifications. The availability of suitable testing equipment in the laboratory influenced the choice of a resonance frequency and output voltage for a 3.6 kW system.
A parameter design method of LC filter circuit for closed‐loop dynamic power supply system based on linear power amplifier
Authors: Yang Feixiang , Wang Xueqing , Luo Jin , Duan Qianwen , Ning Zongqi , Mao Yao
Published: July 2024

The linear power amplifier (LPA) suffers from low power supply utilization in the DC power supply mode, leading to reduced output efficiency. This paper constructs an efficient power supply mode based on closed‐loop dynamic power supply system (CLDPSs). The CLDPSs can generate a pair of bipolar dynamic power supplies based on a predetermined signal to provide power to LPA, which can maintain a small voltage drop between the power supply and the output of LPA, thereby improving the power supply utilization of LPA. In addition, the study also focuses on the conflicting relationship between the output ripple and the dynamic performance of the CLDPSs, for which a new parametric design of the LC filter circuit is proposed, aiming to achieve a balance between these two aspects. Finally, a voice coil motor driving platform is constructed for experimental testing. The results demonstrate that the output ripple and dynamic performance of the CLDPSs can be balanced. In comparison to the DC power supply mode, the CLDPSs power supply mode can enhance the efficiency of LPA by 2 times while the driving accuracy of voice coil motor is basically unchanged.
Model selection techniques for seafloor scattering statistics in synthetic aperture sonar images of complex seafloors
Authors: Olson Derek R. , Geilhufe Marc
Published: July 2024

In quantitative analysis of seafloor scattering measurements, it is common to model the single‐point probability density function of the scattered intensity or amplitude. For more complex seafloors, the pixel amplitude distribution has previously been modelled with a mixture model consisting of two K distributions, but the environment may have more identifiable scattering mechanisms. Choosing the number of components of a mixture model is a decision that must be made, using a priori information, or using a data driven approach. Several common model selection techniques from the statistics literature are explored (the Akaike, Bayesian, deviance, and Watanabe‐Akaike information criteria) and compared to the authors' choice. Examples are given for synthetic aperture sonar data collected by an autonomous underwater vehicle in a rocky environment off the coast of Bergen, Norway, using the HISAS‐1032 synthetic aperture sonar system. The Bayesian information criterion aligned most closely with the interpretation of both the acoustic images and the plots of the probability of false alarm.
Deriving the star formation histories of galaxies from spectra with simulation-based inference
Authors: Iglesias-Navarro Patricia , Huertas-Company Marc , Martín-Navarro Ignacio , Knapen Johan H. , Pernet Emilie
Published: July 2024

High-resolution galaxy spectra encode information about the stellar populations within galaxies. The properties of the stars, such as their ages, masses, and metallicities, provide insights into the underlying physical processes that drive the growth and transformation of galaxies over cosmic time. We explore a simulation-based inference (SBI) workflow to infer from optical absorption spectra the posterior distributions of metallicities and the star formation histories (SFHs) of galaxies (i.e. the star formation rate as a function of time). We generated a dataset of synthetic spectra to train and test our model using the spectroscopic predictions of the MILES stellar population library and non-parametric SFHs. We reliably estimate the mass assembly of an integrated stellar population with well-calibrated uncertainties. Specifically, we reach a score of 0.97 R2 for the time at which a given galaxy from the test set formed 50% of its stellar mass, obtaining samples of the posteriors in only 10−4 s. We then applied the pipeline to real observations of massive elliptical galaxies, recovering the well-known relationship between the age and the velocity dispersion, and show that the most massive galaxies (σ ∼ 300 km s−1) built up to 90% of their total stellar masses within 1 Gyr of the Big Bang. The inferred properties also agree with the state-of-the-art inversion codes, but the inference is performed up to five orders of magnitude faster. This SBI approach coupled with machine learning and applied to full spectral fitting makes it possible to address large numbers of galaxies while performing a thick sampling of the posteriors. It will allow both the deterministic trends and the inherent uncertainties of the highly degenerated inversion problem to be estimated for large and complex upcoming spectroscopic surveys, such as DESI, WEAVE, or 4MOST.
Projection factor and radii of Type II Cepheids
Authors: Wielgórski P. , Pietrzyński G. , Gieren W. , Zgirski B. , Górski M. , Storm J. , Nardetto N. , Kervella P. , Bras G. , Hajdu G. , Hocdé V. , Pilecki B. , Narloch W. , Karczmarek P. , Pych W. , Chini R. , Hodapp K.
Published: July 2024

Context. Type II Cepheids are old pulsating stars that can be used to trace the distribution of an old stellar population and to measure distances to globular clusters and galaxies within several megaparsecs, and by extension, they can improve our understanding of the cosmic distance scale. One method that can be used to measure the distances of Type II Cepheids relies on period-luminosity relations, which are quite widely explored in the literature. The semi-geometrical Baade-Wesselink technique is another method that allows distances of radially pulsating stars, such as Type II Cepheids, to be measured if the so-called projection factor is known. However, the literature concerning this parameter for Type II Cepheids is limited to just a few pioneering works.

Aims. In determining projection factors for eight nearby short-period Type II Cepheids, also known as BL Her type stars, we aim to calibrate the Baade-Wesselink method for measuring distances for this class of stars.

Methods. Using the surface brightness-colour relation version of the Baade-Wesselink technique, we determined the projection factors and radii of eight nearby BL Her type stars. We adopted accurate distances of target stars from Gaia Data Release 3. Time series photometry in the V and KS bands have been collected with two telescopes located at the RolfChini Cerro Murphy Observatory (former Cerro Armazones Observatory), while spectroscopic data have been obtained within dedicated programmes with instruments hosted by the European Southern Observatory.

Results. The measured projection factors for the stars with good quality data are in the range between 1.21 and 1.36. The typical uncertainty of projection factors is 0.1. The mean value is 1.330 ± 0.058, which gives the uncertainty of ∼4%. The main sources of uncertainty on the p-factors are statistical errors of the Baade-Wesselink fit (related to the dispersion and coverage of light and radial velocity curves) and parallax. In the case of radii, the biggest contribution to the error budget comes from the KS band photometry’s systematic uncertainty and parallax. The determined radii allowed us to construct the period-radius relation for BL Her stars. Our period-radius relation is in good agreement with the previous empirical calibration, while two theoretical calibrations found in the literature agree with our relation within 2σ. We also confirm that BL Her and RR Lyr stars obey an apparent common period-radius relation.
Nova contributions to the chemical evolution of the Milky Way
Authors: Kemp Alex J. , Karakas Amanda I. , Casey Andrew R. , Côté Benoit , Izzard Robert G. , Osborn Zara
Published: July 2024

Context. The explosive burning that drives nova eruptions results in unique nucleosynthesis that heavily over-produces certain isotopes relative to the solar abundance. However, novae are often ignored when considering the chemical evolution of our Galaxy due to their low ejecta masses. Galactic chemical evolution studies including novae are rare and have previously relied upon simplified treatments for the behaviour of nova populations.

Aims. In this work, we use previously computed synthetic nova populations and the galactic chemical evolution code OMEGA+ to assess the impact that novae have on the evolution of stable elemental and isotopic abundances.

Methods. We combine populations of novae computed using the binary population synthesis code binary_c with the galactic chemical evolution code OMEGA+ and detailed, white dwarf mass-dependent nova yields to model the nucleosynthetic contributions of novae to the evolution of the Milky Way. We consider three different nova yield profiles, each corresponding to a different set of nova yield calculations.

Results. We examine which nova sites contribute most to which isotopes. Despite novae from low-mass white dwarfs (WDs) dominating nova ejecta contributions, we find that novae occurring on massive WDs are still able to contribute significantly to many isotopes, particularly those with high mass numbers. We find that novae can produce up to 35% of the Galactic 13C and 15N mass by the time the model Galaxy reaches [Fe/H] = 0, and earlier in the evolution of the Galaxy (between [Fe/H] = −2 and −1) novae may have been the dominant source of 15N. Predictions for [13C/Fe], [15N/Fe], 12C/13C, and 14N/15N abundances ratios vary by up to 0.2 dex at [Fe/H] = 0 and by up to 0.7 dex in [15N/Fe] and 14N/15N between [Fe/H] = −2 and −1 (corresponding approximately to Galactic ages of 170 Myr and 1 Gyr in our model). The Galactic evolution of other stable isotopes (excluding Li) is not noticeably affected by including novae. For most isotopes, agreement is generally good between the three different yield profiles we consider. Isotopes where agreement is relatively poor include: 3He (especially at high MWD), 7Li, 18O, 18F, and the > 1.3 M⊙ regime of 29Si, 33S, 34S, 35Cl, and 36Ar.
Essor des communications optique en espace libre
Authors: Grillot Frédéric , Pes Salvatore
Published: July 2024

L’essor des communications en espace libre transforme notre façon de partager l’information. La photonique moyen infrarouge y joue un rôle essentiel, permettant des échanges plus rapides et sécurisés, et ouvrant ainsi de nouvelles perspectives passionnantes pour les liaisons optiques.
Home country’s economic and political institutions: firms’ ownership decisions in cross-border acquisitions
Authors: Chan Christine M. , Shi Lei , Yi Jingtao
Published: July 2024

The influences of a home country’s economic and political institutions on acquirers’ cross-border acquisitions (CBAs) ownership strategies remains unexplored. Acquirers face endogenous uncertainty (i.e., uncertainty that can be resolved in part by acquirers) when transferring headquarters resources to foreign target firms and exogenous uncertainty (i.e., uncertainty that cannot be resolved by acquirers) when there is an unpredictable policy change. We argue that well-developed economic and political institutions in a home country play a market-supporting and constraining role in mitigating endogenous and exogenous uncertainty respectively, enabling acquirers to seek high ownership stakes in CBAs. We also argue that the importance of a home country’s well-developed economic and political institutions for acquirers’ CBA ownership strategic decisions depends on mutual trade dependence between the acquirers’ home country and the target firms’ host countries and also on the economic capabilities of the acquirers developed in different industries and political capabilities developed in different host countries. To test these arguments, we analyze 133,623 CBAs between 2000 and 2020 and find support for the distinct roles played by a home country’s economic and political institutions.
Environmental and performance impacts of 2-ethylhexyl nitrate and ethanol in diesel blends: A comprehensive study
Authors: Salmani Mahir Husain , Hussain Inayat , Rehman Sanaur , Kumar Himansh
Published: July 2024

This study investigates the performance and emissions of a compression ignition engine fueled with blends of ethanol and petroleum diesel with 2-EHN (2 ethylhexyl nitrate) as a cetane improver. Three blends, named E20 (20% ethanol with 80% diesel), E20A (20% ethanol, 0.1% 2-EHN, and 79.9% petroleum diesel), E20B (20% ethanol, 0.2% 2-EHN, and 79.8% petroleum diesel), and petroleum diesel were analyzed for their brake thermal efficiency (BTHE), specific fuel consumption, net heat release rate, indicated thermal efficiency, and emissions of carbon monoxide (CO), CO2, hydrocarbon (HC), and NOx. The experiments were conducted at variable loading conditions and at compression ratio of 16.5. Results showed that at no load conditions, petroleum diesel exhibited higher indicated power (IP) compared to E20, E20A, and E20B. However, at full load conditions, blend E20B showed higher IP compared to petroleum diesel, E20, and E20A. The blend E20B at a compression ratio of 16.5 showed the highest BTHE of 27%, compared to petroleum diesel (25%) under full load conditions, making it a better performing fuel. However, at higher loads and compression ratio of 16.5, the blends E20A and E20B exhibited emissions of CO, HC, CO2, and NOx that were significantly higher than diesel and E20 at all load conditions. Specifically, at full load conditions and compression ratio of 16.5, the emissions for each fuel were as follows: CO emission for E20, E20A, and E20B was around 0.01%, much less than petroleum diesel (0.1%); HC emission for E20 (15 ppm), E20A (17 ppm), E20B (10 ppm) was much higher than petroleum diesel (2.5 ppm); CO2 emission for E20, E20A, and E20B was about 13% less than petroleum diesel (15%); and NOx emission for E20, E20A, and E20B was around 150 ppm, comparable with petroleum diesel (140 ppm). These results imply that further improvements are required in using ethanol blended alternate fuel in diesel engines with 2-EHN (cetane improver) to reduce emissions with improved performance.
Dependence of the incorporated boron concentration near SiO2/4H–SiC interface on trap passivation reduction
Authors: Wang Runze , Noguchi Munetaka , Watanabe Hiroshi , Kita Koji
Published: July 2024

By systematically varying the boron concentration near the oxide/4H–SiC interface within a specifically designed boron-diffusion layer oxide structure, this paper explores the influence of boron concentration on interface state density and near-interface trap density in 4H–SiC MOS capacitors. Additionally, the effect of boron near the oxide/4H–SiC interface on device stability under elevated temperature conditions was examined. The boron species were introduced into the SiO2/4H–SiC interface by spin coating followed by annealing, whose temperature controls the amount of boron present in the near interface region. It is suggested that a higher concentration of boron leads to a better trap passivation effect while preserving the stability of flat band voltage.
A magnetic anomaly and particle velocity array correlator for the detection of internal waves in the ocean
Authors: Nieves Eric , Beaujean Pierre-Philippe , Soto Andrew Tarantul , Dhanak Manhar
Published: July 2024

Related literature has shown that internal waves (IWs) observed in the ocean are capable of producing secondary magnetic fields with a small signal-to-noise ratio due to the flow of dissolved salts. It can be difficult to characterize these signals since they are relatively weak, highly transient, and capable of being multi-modal. Using data collected by an array of magnetometers and acoustic Doppler current profilers, a technique called magnetic anomaly and particle velocity array correlator was developed for the detection of IWs. By using a combination of filtering techniques and a multi-variate correlation step, peak correlations above 90% were shown between the magnetic and water particle velocity records of potential IWs.
The construction and theoretical investigation of compound-protein target-pathway network for Radix Pueraria
Authors: Zhang Xueyan , Li Yunhua , Xie Bin , Chen Fei
Published: July 2024

The complex network approach is an effective method to analyze the global properties of complex biological systems, which can be used to explore the interactions between multiple compounds and protein targets of drug. Radix Pueraria has a long history of efficacy in different diseases, containing a variety of compounds that can produce multiple therapeutic effects via multiple targets. To explore the interrelationship between compounds of Radix Pueraria, protein targets, and pathways, the present investigation used the complex network approach to construct the compound-protein target-pathway network of Radix Pueraria. The analysis of the statistical and topological characteristics shows that the network has small-world and scale-free characteristics. The diameter of the network is 7, indicating that the information exchange between two nodes could quickly spread to the whole network. With the rank of degree value and integrated centrality as identification indicators, by taking the threshold of integrated centrality as 0.70, a total of nine key hub nodes containing three active compounds, two protein targets, and four biological pathways were identified: genistein, daidzein, puerarin, MAPK3, MAPK1, hsa01100, hsa05200, hsa05417, and hsa05207. The network analysis suggests these key hub nodes should play an important role in the pharmacological action of Radix Pueraria. The results of this study provide useful information and knowledge for further exploring the pharmacological mechanism of Radix Pueraria in the course of disease treatment.
Modeling the longitudinal wave in a nanorod based on a novel theory of elastic waves with surface effects
Authors: Jia Ning
Published: July 2024

This paper investigates the impact of surface effects on the propagation behavior of longitudinal waves in a nanorod. A theoretical model has been established on the basis of a newly proposed theory of elastic waves with surface effects. The surface effects comprise two components: the effect of surface energy and the effect of surface inertia. An analytical formula for the longitudinal wave velocity of a nanorod has been derived. Two inherent lengths at nanoscale have been deduced to characterize these two types of surface effects. The results indicate that the longitudinal wave in a nanorod is still nondispersive. However, an attractive phenomenon uncovered is that when the size of a rod reduces to the inherent lengths at nanoscale, the longitudinal wave velocity becomes size-dependent due to the effects of surface energy and surface inertia. The former increases the longitudinal wave velocity, whereas the latter decreases it. This can be understood as the former equivalently increasing the stiffness of the nanorod, whereas the latter enhancing its effective density. On the other hand, when the rod is at the macroscale, the longitudinal wave velocity degenerates to the classical velocity for a macroscopic rod without any surface effects. The current findings not only enhance our understanding of the size-dependent wave velocity of longitudinal waves in nanorods but also facilitate precisely designing the elastic wave nanodevices.
The threat from cosmic flotsam
Authors: Boslough Mark
Published: July 2024

A power-law distribution of asteroid impacts on Earth spans 13 orders of magnitude in energy. The risk is dominated by low-probability but high-consequence events.
Metamaterial device makes 16 polarization measurements at once
Authors: Miller Johanna L.
Published: July 2024

Capturing all the ways that an object can affect a light wave’s polarization has always been cumbersome. Now it can be done in an instant.
Effects of β-carotene supplementation and age on the oxidative status, production and reproductive performance of grazing ewes
Authors: Ahmed Osman , Hassen Abubeker , Lehloenya Khoboso
Published: July 2024

Context There is some evidence that physiological stages such as breeding, pregnancy, parturition and lactation may trigger oxidative stress. It has also been observed in several species, including sheep, that age affects their vulnerability to oxidative stress. Aims This study investigated the effects of supplemental β-carotene and age on the oxidative status of grazing ewes around breeding, pregnancy, parturition and early lactation as well as on their production and reproduction performance. Methods Hundred and four ewes were divided into two broad age groups (young = 1–3 years, and old = 4–6 years). Within age groups, ewes of similar age were randomly assigned to four treatment groups (A1, A2, A3, C) by using a completely randomised block design. The young (n = 13) and old (n = 13) sheep in Groups A1, A2 and A3 were daily drenched with 100 mg, 75 mg and 50 mg β-carotene respectively. Group C was unsupplemented (Control). Supplementation lasted 28 days before oestrus synchronisation; 14 days during oestrus synchronisation (CIDR) and hand-mating; 18 days post-hand-mating; 30 days before lambing; and 15 days after lambing. All animals were grazed on Kikuyu grass (Pennisetum clandestinum). Six ewes from each group (total = 24) were sampled for blood to measure oxidative and hormonal status during the experiment. Key results Supplemental β-carotene at ≥75 mg/day may act as a pro-oxidant in ruminants under oxidatively stressed conditions such as parturition. Age did not affect the ewes’ oxidative status. The supplemental β-carotene did not affect bodyweight, oestrus parameters, corpus luteum size, conception rate and litter size. Except for a tendency of lambs from supplemented ewes to have heavier weight at 15 days old (P = 0.080), age group and supplemental β-carotene did not affect the lamb mortality rate or weight at birth or 15 days old. Older ewes showed earlier and longer duration of oestrus than did younger ewes. Conclusions Supplementation of grazing ewes with β-carotene should not be ≥75 mg/day, especially at parturition period, because it may work as a pro-oxidant. The older ewes seem to have earlier oestrus with a longer duration than do the younger ones. Implications Caution is urged when administering high doses of β-carotene to ewes during the peri-parturient period.
The chronology of the human colonization of the Canary Islands
Authors: Santana Jonathan , del Pino Miguel , Morales Jacob , Fregel Rosa , Hagenblad Jenny , Morquecho Aarón , Brito-Mayor Aitor , Henríquez Pedro , Jiménez Jared , Serrano Javier G. , Sánchez-Cañadillas Elías , Ordóñez Alejandra C. , Gilson Simon-Pierre
Published: July 2024

The human colonization of the Canary Islands represents the sole known expansion of Berber communities into the Atlantic Ocean and is an example of marine dispersal carried out by an African population. While this island colonization shows similarities to the populating of other islands across the world, several questions still need to be answered before this case can be included in wider debates regarding patterns of initial colonization and human settlement, human–environment interactions, and the emergence of island identities. Specifically, the chronology of the first human settlement of the Canary Islands remains disputed due to differing estimates of the timing of its first colonization. This absence of a consensus has resulted in divergent hypotheses regarding the motivations that led early settlers to migrate to the islands, e.g., ecological or demographic. Distinct motivations would imply differences in the strategies and dynamics of colonization; thus, identifying them is crucial to understanding how these populations developed in such environments. In response, the current study assembles a comprehensive dataset of the most reliable radiocarbon dates, which were used for building Bayesian models of colonization. The findings suggest that i) the Romans most likely discovered the islands around the 1st century BCE; ii) Berber groups from western North Africa first set foot on one of the islands closest to the African mainland sometime between the 1st and 3rd centuries CE; iii) Roman and Berber societies did not live simultaneously in the Canary Islands; and iv) the Berber people rapidly spread throughout the archipelago.
Design principles of multi-map variation in biological systems
Authors: Poyatos Juan F
Published: July 2024

Complexity in biology is often described using a multi-map hierarchical architecture, where the genotype, representing the encoded information, is mapped to the functional level, known as the phenotype, which is then connected to a latent phenotype we refer to as fitness. This underlying architecture governs the processes driving evolution. Furthermore, natural selection, along with other neutral forces, can, in turn, modify these maps. At each level, variation is observed. Here, I propose the need to establish principles that can aid in understanding the transformation of variation within this multi-map architecture. Specifically, I will introduce three, related to the presence of modulators, constraints, and the modular channeling of variation. By comprehending these design principles in various biological systems, we can gain better insights into the mechanisms underlying these maps and how they ultimately contribute to evolutionary dynamics.
Skyrmion motion induced by spin-waves on magnetic nanotubes
Authors: Abdulrazak Tijjani , Liu 刘 Xuejuan 雪娟 , Wang 王 Zhenyu 振宇 , Cao 曹 Yunshan 云姗 , Yan 严 Peng 鹏
Published: July 2024

We investigate the skyrmion motion driven by spin waves on magnetic nanotubes through micromagnetic simulations. Our key results include demonstrating the stability and enhanced mobility of skyrmions on the edgeless nanotube geometry, which prevents destruction at boundaries — a common issue in planar geometries. We explore the influence of the damping coefficient, amplitude, and frequency of microwaves on skyrmion dynamics, revealing a non-uniform velocity profile characterized by acceleration and deceleration phases. Our results show that the skyrmion Hall effect is significantly modulated on nanotubes compared to planar models, with specific dependencies on the spin-wave parameters. These findings provide insights into skyrmion manipulation for spintronic applications, highlighting the potential for high-speed and efficient information transport in magnonic devices.
Iron-carbon based materials as negative electrode for energy storage devices
Authors: Thi Hang Bui , Thi Lan Nguyen
Published: July 2024

The effect of various carbon nanofibers (CNF) on the electrochemical properties of iron/carbon (Fe/C) composite electrodes has been investigated to find a suitable carbon additive for iron-based battery anode. The structure and characteristics of carbon such as particle size, surface area strongly affected the cycling performance of Fe/C composite electrode. Different types of CNF structures (herringbone and tubular) have been investigated and tubular type exhibited higher discharge capacity. The x-ray energy dispersive spectroscopy (EDS) revealed that iron species are dispersed on carbon surface during cycling, which may improve the electrochemical properties of the Fe/C composite electrodes. The aggregation of iron species into large particles on the carbon surface via dissolution-deposition process during cycling increased the resistance of the Fe/C electrode. This phenomenon caused the reduced redox current and discharge capacity of electrode during cycling. The electrochemical active material type and their particle size also influenced the cycling performance of electrode. When Fe was replaced by Fe2O3, the Fe2O3/C composite electrode provided larger capacity than Fe/C composite electrode. The discharge capacity of nano-Fe2O3/tubular CNF composite electrode was larger than that of micro-Fe2O3/tubular CNF composite electrode.
An algebraic model for the free loop space
Authors: Rivera Manuel
Published: July 2024

We describe an algebraic chain level construction that models the passage from an arbitrary topological space to its free loop space. The input of the construction is a categorical coalgebra, i.e., a curved coalgebra satisfying certain properties, and the output is a chain complex. The construction is a modified version of the co-Hochschild complex of a differential graded (dg) coalgebra. When applied to the chains on an arbitrary simplicial set

X
X

, appropriately interpreted, it yields a chain complex that is naturally quasi-isomorphic to the singular chains on the free loop space of the geometric realization of

X
X

. We relate this construction to a twisted tensor product model for the free loop space constructed using the adjoint action of a dg Hopf algebra model for the based loop space.
Topology of the moduli spaces of Higgs bundles over abelian varieties
Authors: Biswas Indranil , Florentino Carlos , Nozad Azizeh
Published: July 2024

Let

G
G

be a complex reductive group and

A
A

be an Abelian variety of dimension

d
d

over

C

\mathbb {C}

. We determine the Poincaré polynomial and also the mixed Hodge polynomial of the moduli spaces

M

A

H

(
G
)

\mathcal {M}_{A}^{H}(G)

of

G
G

-Higgs bundles over

A
A

. We show that these are normal varieties with symplectic singularities, when

G
G

is a classical semisimple group. For

G

=

GL

n

(

C

)

G\,=\,\text {GL}_{n}(\mathbb {C})

, we also compute Poincaré polynomials of natural desingularizations of

M

A

H

(
G
)

\mathcal {M}_{A}^{H}(G)

and of

G
G

-character varieties of free abelian groups, in some cases. In particular, explicit formulas are obtained when

dim
⁡
A

=

d

=

1

\dim A\,=\, d\,=\,1

, and also for rank 2 and 3 Higgs bundles, for arbitrary

d

>

1

d\,>\,1

.
The Nehru-Era Economic History and Thought & Their Lasting Impact
Authors: Panagariya Arvind
Published: July 2024

At independence in 1947, Prime Minister Jawaharlal Nehru embarked upon two foundational projects to build modern India: a political project aimed at establishing democracy and an economic one aimed at ending poverty. Three-quarters of a century later, his political project is a resounding success, but the opposite is true of the economic one. While much has been written in recent years on the Nehru-era political history and thought and its impact on post-independence India, no such work on the economic side exists. The present volume fills this gap. It draws on numerous contemporary documents and writings to examine the evolution of Nehru’s economic philosophy with socialism, self-sufficiency, and heavy-industry development at its core. It discusses in full detail the historical circumstances and contemporary thought that led to near unanimity on adopting a development model that, in hindsight, was deeply and obviously flawed. It goes on to highlight how the focus on heavy industry and self-sufficiency translated into myriad inefficiencies and an exclusionary development model that left all but a small elite out of the mainstream growth process. The volume goes on to argue that the entrenchment of socialist thought within the country’s democratic polity effectively ruled out any major change of course for many decades. The bequest of socialist thought from one generation to the next led to its perpetuation among politicians, bureaucrats, intellectuals, and even businessmen. The result was that alternative ideas failed to germinate, with a change of course ruled out until an economic crisis closed all other options.
Industrial and Labor Policies
Authors: Panagariya Arvind
Published: July 2024

The Statement of Industrial Policy of 1945 represented the maiden attempt to bring the key industries under the purview of the central government. But it remained unimplemented. Its successor, the Industrial Policy Resolution of 1948 (IPR 1948), accomplish the task, giving monopoly to the state over arms and ammunition, atomic energy, and railways and exclusive right to it for establishing new enterprises in certain industries. But it ruled out nationalization of private enterprises for ten years. Its implementing legislation, the Industries (Development and Regulation) Act of 1951 (IDRA 1951), provided for the licensing and regulation of private industry. With Sardar Vallabhbhai Patel, a champion of private enterprise, gone in December 1950, Nehru replaced IPR 1948 by IPR 1956, which significantly expanded the scope of the public sector. The late 1940s also saw the enactment of numerous restrictive labor laws including the Industrial Disputes Act of 1947, Minimum Wage Act of 1948, and the Factories Act of 1948.
The Political Leadership II
Authors: Panagariya Arvind
Published: July 2024

Rajiv Gandhi (RG), son of Indira Gandhi (IG), came to the prime ministerial office without the baggage of socialism. He embarked upon a major liberalization program in his very first year. But nearly all senior leaders of his party, who had cut their political teeth under Nehru or IG, opposed and derailed him by his second year. The RG experiment thus ended without success. The real change came in mid-1991 after RG’s exit and the fall of two other governments in quick succession. The assassination of RG during the election campaign in May 1991 brought the more senior Narasimha Rao to the office. As a member of their cabinets, Rao had closely observed the liberalization experiments under IG and RG in the 1980s. Taking advantage of those experiences and the ongoing balance of payments crisis, he carefully navigated liberalizing reforms, nudging India toward a market economy. Though Rao thus changed the direction of policy, socialist thought has continued to impede progress toward turning India into a full-throttled market economy.
Measurement Issues
Authors: Antony Alexander K , Thompson William R
Published: July 2024

This chapter discusses a valid and reliable measure of industrialization transition. It provides an overview of the claims regarding how industrialization is vital to evaluating the fit of the most prominent explanations of peace in international relations. Variables related to industrialization tend to approximate wealth more than the structure of a state’s economy. Moreover, industrialization brought about major changes in the diversification of labor; as such, it became a crucial step in allowing populations to transition from agricultural labor to other forms of labor. The chapter then looks into the measure of democracy, economic interdependence, border settlement, and peace factors.
Habeas corpus comes to America
Authors: Tyler Amanda L.
Published: July 2024

As this chapter details, in the newly formed United States, the principles of the English Habeas Corpus Act firmly and finally took root. Surveying this period, one finds pervasive evidence that the Act and its protections wielded profound influence over the development of early American habeas jurisprudence and that American law also imported a robust common law writ of habeas corpus to reach cases beyond the scope of the English Act. As the chapter explores, many states adopted the terms of the English Habeas Corpus Act and even suspended those protections during the Revolutionary War. As the chapter also highlights, it was the English Act that proved a key foundation of the habeas clause in the United States Constitution, known as the Suspension Clause.
Line-field confocal optical coherence tomography for real-time differential diagnosis of toxic epidermal necrolysis versus staphylococcal scalded skin syndrome
Authors: Klepfisch Lucas , Ben-Said Benoit , Ribereau-Gayon Emmanuel , Kanitakis Jean , Danset Marie
Published: July 2024

We present the cases of a 31-year-old man and a 68-year-old woman, who presented with extensive erythema, a positive Nikolsky sign and significant pain. Line-field confocal optical coherence tomography is a fast imaging tool that can be used to visualize cleavage level and epidermal necrosis to distinguish staphylococcal scalded skin syndrome from toxic epidermal necrolysis.
The role of digital tools and emerging devices in COVID-19 contact tracing during the first 18 months of the pandemic: a systematic review
Authors: Unim Brigid , Zile-Velika Irisa , Pavlovska Zane , Lapao Luis , Peyroteo Mariana , Misins Janis , Forjaz Maria João , Nogueira Paulo , Grisetti Tiziana , Palmieri Luigi
Published: July 2024

Background

Contact tracing is a public health intervention implemented in synergy with other preventive measures to curb epidemics, like the coronavirus pandemic. The development and use of digital devices have increased worldwide to enhance the contact tracing process. The aim of the study was to evaluate the effectiveness and impact of tracking coronavirus disease 2019 (COVID-19) patients using digital solutions.

Methods

Observational studies on digital contact tracing (DCT), published 2020–21, in English were identified through a systematic literature review performed on nine online databases. An ad hoc form was used for data extraction of relevant information. Quality assessment of the included studies was performed with validated tools. A qualitative synthesis of the findings is reported.

Results

Over 8000 records were identified and 37 were included in the study: 24 modelling and 13 population-based studies. DCT improved the identification of close contacts of COVID-19 cases and reduced the effective reproduction number of COVID-19-related infections and deaths by over 60%. It impacted positively on societal and economic costs, in terms of lockdowns and use of resources, including staffing. Privacy and security issues were reported in 27 studies.

Conclusions

DCT contributed to curbing the COVID-19 pandemic, especially with the high uptake rate of the devices and in combination with other public health measures, especially conventional contact tracing. The main barriers to the implementation of the devices are uptake rate, security and privacy issues. Public health digitalization and contact tracing are the keys to countries’ emergency preparedness for future health crises.
Patterns of Genetic Diversity and Gene Flow Associated With an Aridity Gradient in Populations of Common Mole-rats, Cryptomys hottentotus hottentotus
Authors: Merchant Hana N , Ivanova Anastasia , Hart Daniel W , García Cristina , Bennett Nigel C , Portugal Steven J , Faulkes Chris G
Published: July 2024

Genetic adaptation is the change of a population toward a phenotype that best fits the present ecological conditions of the environment it inhabits. As environmental conditions change, allele frequencies shift, resulting in different populations of the same species possessing genetic variation and divergent phenotypes. Cooperatively breeding common mole-rats (Cryptomys hottentotus hottentotus) inhabit environments along an aridity gradient in South Africa, which provides an opportunity for local genetic adaptations to occur. Using one mitochondrial gene (cytochrome b) and 3,540 SNP loci across the whole genome, we determined the phylogenetic relationship, population structure and genetic diversity of five populations of C. h. hottentotus located along an aridity gradient. Mitochondrial data identified population-specific clades that were less distinct in the two mesic populations, potentially indicating historical or recent gene flow, or the retention of ancestral haplotypes. Arid and semi-arid populations formed a distinct cluster from the non-arid populations. Genetic diversity and gene flow were higher in arid-dwelling individuals, suggesting greater connectivity and interactions between colonies in arid regions in comparison to mesic ones. Using an Aridity Index, we determined that isolation by environment, rather than isolation by geographical distance, best explains the genetic distance between the populations. Further analyses using target loci may determine if there are differing underlying genetic adaptations among populations of C. h. hottentotus. These analyses could help unravel population differences in response to environmental factors within a subspecies of bathyergid mole-rat and determine the adaptive capacity of this small nonmigratory subterranean rodent species in response to aridification in the face of climate change.