bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-shot decoherence polarization gated imaging through turbid media
Authors: Ren Yuhu , Jian Jimo , Tan Wenjiang , Wang Jing , Chen Tao , Zhang Haikun , Xia Wei
Published: July 2023

We propose a method for imaging through a turbid medium by using a single-shot decoherence polarization gate (DPG). The DPG is made up of a polarizer, an analyzer, and a weakly scattering medium. Contrary to intuition, we discover that the preferential utilization of sparsely scattered photons by introducing weakly scattering mediums can lead to better image quality. The experimental results show that the visibilities of the images acquired from the DPG imaging method are obviously improved. The contrast of the bar can be increased by 50% by the DPG imaging technique. Furthermore, we study the effect of the volume concentration of the weakly scattering medium on the speckle suppression and the enhancement of the visibilities of the images. The variances of the contrasts of the image show that there exists an optimum optical depth (∼0.8) of the weakly scattering medium for DPG imaging through a specific turbid medium.
Do pre-exposure prophylaxis (PrEP) users engaging in chemsex experience their participation as problematic and how can they best be supported? Findings from an online survey in Belgium
Authors: Vanbaelen T. , Rotsaert A. , Van Landeghem E. , Nöstlinger C. , Vuylsteke B. , Platteau T. , Herrijgers C. , Reyniers T.
Published: July 2023

Background Chemsex involves the use of psychoactive drugs in a sexual context and is a growing phenomenon among men who have sex with men (MSM) and pre-exposure prophylaxis (PrEP) users. Investigating how its negative consequences can be avoided is important. The objective of this study was to explore the perceived impact of chemsex, the willingness to reduce chemsex activities and associated risks and preferred interventions to do so among PrEP users. Methods We analysed data from an online survey among PrEP users in Belgium. Chemsex was assessed in two questionnaires distributed between September 2020 and January 2022. Results A total of 326 participants completed the baseline questionnaire, and 186 the follow-up questionnaire. About one in three participants (36.5%, 119/326) reported engaging in chemsex, and half of those (49.6%, 59/119) were willing to reduce chemsex-related risks. The most preferred strategies for reducing risks were online support via an app (37.3%, 22/59) and face-to-face counselling with a health care professional (30.5%, 18/59). Among those reporting recent chemsex in the follow-up questionnaire, about one in five (21.9%, 14/64) wanted to reduce or stop chemsex activities. About 23.4% (15/64) also reported experiencing negative consequences of chemsex on their health, social or professional life. Conclusion Our findings show that one in four PrEP users engaging in chemsex experienced negative consequences of these activities and about one in five was willing to reduce or stop chemsex activities. We recommend embedding comprehensive chemsex support in the PrEP package of care and developing novel tools and interventions in order to reach maximum impact.
Experimental evidence for structured information–sharing networks reducing medical errors
Authors: Centola Damon , Becker Joshua , Zhang Jingwen , Aysola Jaya , Guilbeault Douglas , Khoong Elaine
Published: July 2023

Errors in clinical decision-making are disturbingly common. Recent studies have found that 10 to 15% of all clinical decisions regarding diagnoses and treatment are inaccurate. Here, we experimentally study the ability of structured information–sharing networks among clinicians to improve clinicians’ diagnostic accuracy and treatment decisions. We use a pool of 2,941 practicing clinicians recruited from around the United States to conduct 84 independent group-level trials, ranging across seven different clinical vignettes for topics known to exhibit high rates of diagnostic or treatment error (e.g., acute cardiac events, geriatric care, low back pain, and diabetes-related cardiovascular illness prevention). We compare collective performance in structured information–sharing networks to collective performance in independent control groups, and find that networks significantly reduce clinical errors, and improve treatment recommendations, as compared to control groups of independent clinicians engaged in isolated reflection. Our results show that these improvements are not a result of simple regression to the group mean. Instead, we find that within structured information–sharing networks, the worst clinicians improved significantly while the best clinicians did not decrease in quality. These findings offer implications for the use of social network technologies to reduce errors among clinicians.
Mesoamerican urbanism revisited: Environmental change, adaptation, resilience, persistence, and collapse
Authors: Chase Diane Z. , Lobo José , Feinman Gary M. , Carballo David M. , Chase Arlen F. , Chase Adrian S. Z. , Hutson Scott R. , Ossa Alanna , Canuto Marcello , Stanton Travis W. , Gorenflo L.J. , Pool Christopher A. , Arroyo Barbara , Liendo Stuardo Rodrigo , Nichols Deborah L.
Published: July 2023

Urban adaptation to climate change is a global challenge requiring a broad response that can be informed by how urban societies in the past responded to environmental shocks. Yet, interdisciplinary efforts to leverage insights from the urban past have been stymied by disciplinary silos and entrenched misconceptions regarding the nature and diversity of premodern human settlements and institutions, especially in the case of prehispanic Mesoamerica. Long recognized as a distinct cultural region, prehispanic Mesoamerica was the setting for one of the world’s original urbanization episodes despite the impediments to communication and resource extraction due to the lack of beasts of burden and wheeled transport, and the limited and relatively late use of metal implements. Our knowledge of prehispanic urbanism in Mesoamerica has been significantly enhanced over the past two decades due to significant advances in excavating, analyzing, and contextualizing archaeological materials. We now understand that Mesoamerican urbanism was as much a story about resilience and adaptation to environmental change as it was about collapse. Here we call for a dialogue among Mesoamerican urban archaeologists, sustainability scientists, and researchers interested in urban adaptation to climate change through a synthetic perspective on the organizational diversity of urbanism. Such a dialogue, seeking insights into what facilitates and hinders urban adaptation to environmental change, can be animated by shifting the long-held emphasis on failure and collapse to a more empirically grounded account of resilience and the factors that fostered adaptation and sustainability.
A metal-free carbon catalyst for oxidative dehydrogenation of aryl cyclohexenes to produce biaryl compounds
Authors: Yang Mingze , Lenarda Anna , Frindy Sana , Sang Yushuai , Oksanen Valtteri , Bolognani Adriano , Hendrickx Lisa , Helaja Juho , Li Yongdan
Published: July 2023

A metal-free route based on a carbon catalyst to synthesize biphenyls through oxidative dehydrogenation (ODH) of phenyl cyclohexene has been investigated. Among the samples examined, an air-oxidized active carbon exhibits the best activity with a 9.1 × 10
−2
h
−1
rate constant, yielding 74% biphenyl in 28 h at 140 °C under five bar O
2
in anisole. The apparent activation energy is measured as 54.5 kJ⋅mol
−1
. The extended reaction scope, consisting of 15 differently substituted phenyl cyclohexenes, shows the wide applicability of the proposed method. The catalyst’s good recyclability over six runs suggests this ODH method as a promising route to access the biaryl compounds. In addition, the reaction mechanism is investigated with a combination of X-ray photoelectron spectroscopy, functional group blocking, and model compounds of carbon catalysts and is proposed to be based on the redox cycle of the quinoidic groups on the carbon surface. Additional experiments prove that the addition of the catalytic amount of acid (methanesulfonic acid) accelerates the reaction. In addition, Hammett plot examination suggests the formation of a carbonium intermediate, and its possible structure is outlined.
High-resolution mapping reveals the mechanism and contribution of genome insertions and deletions to RNA virus evolution
Authors: Aguilar Rangel Mauricio , Dolan Patrick T. , Taguwa Shuhei , Xiao Yinghong , Andino Raul , Frydman Judith
Published: July 2023

RNA viruses rapidly adapt to selective conditions due to the high intrinsic mutation rates of their RNA-dependent RNA polymerases (RdRps). Insertions and deletions (indels) in viral genomes are major contributors to both deleterious mutational load and evolutionary novelty, but remain understudied. To characterize the mechanistic details of their formation and evolutionary dynamics during infection, we developed a hybrid experimental-bioinformatic approach. This approach, called MultiMatch, extracts insertions and deletions from ultradeep sequencing experiments, including those occurring at extremely low frequencies, allowing us to map their genomic distribution and quantify the rates at which they occur. Mapping indel mutations in adapting poliovirus and dengue virus populations, we determine the rates of indel generation and identify mechanistic and functional constraints shaping indel diversity. Using poliovirus RdRp variants of distinct fidelity and genome recombination rates, we demonstrate tradeoffs between fidelity and Indel generation. Additionally, we show that maintaining translation frame and viral RNA structures constrain the Indel landscape and that, due to these significant fitness effects, Indels exert a significant deleterious load on adapting viral populations. Conversely, we uncover positively selected Indels that modulate RNA structure, generate protein variants, and produce defective interfering genomes in viral populations. Together, our analyses establish the kinetic and mechanistic tradeoffs between misincorporation, recombination, and Indel rates and reveal functional principles defining the central role of Indels in virus evolution, emergence, and the regulation of viral infection.
Modeling and design of heterogeneous hierarchical bioinspired spider web structures using deep learning and additive manufacturing
Authors: Lu Wei , Lee Nic A. , Buehler Markus J.
Published: July 2023

Spider webs are incredible biological structures, comprising thin but strong silk filament and arranged into complex hierarchical architectures with striking mechanical properties (e.g., lightweight but high strength, achieving diverse mechanical responses). While simple 2D orb webs can easily be mimicked, the modeling and synthesis of 3D-based web structures remain challenging, partly due to the rich set of design features. Here, we provide a detailed analysis of the heterogeneous graph structures of spider webs and use deep learning as a way to model and then synthesize artificial, bioinspired 3D web structures. The generative models are conditioned based on key geometric parameters (including average edge length, number of nodes, average node degree, and others). To identify graph construction principles, we use inductive representation sampling of large experimentally determined spider web graphs, to yield a dataset that is used to train three conditional generative models: 1) an analog diffusion model inspired by nonequilibrium thermodynamics, with sparse neighbor representation; 2) a discrete diffusion model with full neighbor representation; and 3) an autoregressive transformer architecture with full neighbor representation. All three models are scalable, produce complex, de novo bioinspired spider web mimics, and successfully construct graphs that meet the design objectives. We further propose an algorithm that assembles web samples produced by the generative models into larger-scale structures based on a series of geometric design targets, including helical and parametric shapes, mimicking, and extending natural design principles toward integration with diverging engineering objectives. Several webs are manufactured using 3D printing and tested to assess mechanical properties.
Human infants are aroused and concerned by moral transgressions
Authors: Kassecker Anja , Verschoor Stephan A. , Schmidt Marco F. H.
Published: July 2023

Humans reason and care about ethical issues, such as avoiding unnecessary harm. But what enables us to develop a moral capacity? This question dates back at least to ancient Greece and typically results in the traditional opposition between sentimentalism (the view that morality is mainly driven by socioaffective processes) and rationalism [the view that morality is mainly driven by (socio)cognitive processes or reason]. Here, we used multiple methods (eye-tracking and observations of expressive behaviors) to assess the role of both cognitive and socioaffective processes in infants’ developing morality. We capitalized on the distinction between moral (e.g., harmful) and conventional (e.g., harmless) transgressions to investigate whether 18-mo-old infants understand actions as distinctively moral as opposed to merely disobedient or unexpected. All infants watched the same social scene, but based on prior verbal interactions, an actor’s tearing apart of a picture (an act not intrinsically harmful) with a tool constituted either a conventional (wrong tool), a moral (producing harm), or no violation (correct tool). Infants’ anticipatory looks differentiated between conventional and no violation conditions, suggesting that they processed the verbal interactions and built corresponding expectations. Importantly, infants showed a larger increase in pupil size (physiological arousal), and more expressions indicating empathic concern, in response to a moral than to a conventional violation. Thus, infants differentiated between harmful and harmless transgressions based solely on prior verbal interactions. Together, these convergent findings suggest that human infants’ moral development is fostered by both sociocognitive (inferring harm) and socioaffective processes (empathic concern for others’ welfare).
Variability or its loss in creole endangerment
Authors: Lee Nala H.
Published: July 2023

A language’s endangerment is said to be typified by variation accompanied by some degree of unpredictability. This paper examines if this characterization is appropriate of Baba Malay, an endangered creole, as it is spoken in Singapore. Recent work suggests that the language is much less variable than one expects of a creole. A comparison between historical Baba Malay material and newer Baba Malay material, focusing on the language’s pronominal system, and aspectual and tense system, demonstrates that this is indeed the case. Such variation or an increasing lack of it is not unpredictable, stemming not only from natural language change, but also from changes in the language’s socio-environment. Increasing lack of proficiency in the component languages and a desire among speakers to distinguish themselves from speakers of the lexifier variety may explain some loss in Baba Malay’s variability.
Variability in clusters and continuums
Authors: Gonzales Wilkinson Daniel Wong
Published: July 2023

This study explores the sociolinguistic situation of a
metropolitan Manila Lannang community based on data gathered between 2017 and
2020. A survey was administered to 117 individuals to probe into various
dimensions of self-reported language use (e.g., proficiency, confidence) and
attitudes (e.g., pride). The results show that, among the Lannangs, there is a
range of language use and attitudes, with age and other social factors such as
identity impacting the scope of this variability. This variability appears to
progress along a continuum in some areas, while forming cluster patterns in
others. An examination of the contemporary data alongside data from
investigations done in the late 1980s and 1990s reveals some disparities,
pointing to generational shifts in language use. The findings demonstrate that
the sociolinguistic situation of the Manila Lannang community is unique,
dynamic, and complex, enabling us to gain some insights and a nuanced view of
the sociolinguistic landscape of the broader Asia-Pacific region.
The creativity and limitations of AI neural machine translation
Authors: Hu Kaibao , Li Xiaoqian
Published: July 2023

This study examines the performance of the neural machine translation system DeepL in translating Shakespeare’s
plays Coriolanus and The Merchant of Venice. The aim here is to explore the strengths and
limitations of an AI-based English-Chinese translation of literary texts. Adopting a corpus-based approach, the study investigates
the accuracy and fluency rates, the linguistic features, and the use of various methods of translation in the Chinese translations
of Shakespeare’s plays conducted via DeepL. It compares these to the translations by Liang Shiqiu, a well-known Chinese
translator. The study finds that DeepL performs well in translating these works, with an accuracy and fluency rate of above 80% in
sampled texts, showing the potential of the use of neural machine translation in translating literary texts across distant
languages. Our research further reveals that the DeepL translations exhibit a certain degree of creativity in their use of
translation methods such as addition, explicitation, conversion and shift of perspective, and in the use of Chinese sentence-final
modal particles, as well as Chinese modal verbs. On the other hand, the system appears to be limited in that a certain amount of
translation errors are present, including literal translations.
The cognate continuum
Authors: Strangmann Iris M. , Antolovic Katarina , Hansen Pernille , Simonsen Hanne Gram
Published: July 2023

Cognates, words that are similar in form and meaning across two languages, form compelling test cases for bilingual access and representation. Overwhelmingly, cognate pairs are subjectively selected in a categorical either- or manner, often with criteria and modality unspecified. Yet the few studies that take a more nuanced approach, selecting cognate pairs along a continuum of overlap, show interesting, albeit somewhat divergent results. This study compares three measures that quantify cognateness continuously to obtain modality-specific cognate scores for the same set of Norwegian-English word-translation pairs: (1) Researcher Intuitions – bilingual researchers rate the degree of overlap between the paired words, (2) Levenshtein Distance – an algorithm that computes overlap between word pairs, and (3) Translation Elicitation – English-speaking monolinguals guess what Norwegian words mean. Results demonstrate that cognateness can be ranked on a continuum and reveal measure and modality-specific effects. Orthographic presentation yields higher cognateness status than auditory presentation overall. Though all three measures intercorrelated moderately to highly, Researcher Intuitions demonstrated a bimodal distribution, yielding scores on the high and low end of the spectrum, consistent with the common categorical approach in the field. Levenshtein Distance would be preferred for fine-grained distinctions along the continuum of form overlap.
The emergence of the English dative alternation as a response to
system-wide changes
Authors: Zehentner Eva
Published: July 2023

This chapter revisits the much-discussed question whether a causal
relationship holds between several changes observed in the history of
English; these are (a) the increasing use of prepositional patterns, (b) the
loss of nominal case marking, and (c) the fixation of constituent order.
Located within the same time-period, namely Middle English, there is
relatively broad consensus that the processes are correlated. However, the
extent and directionality of causation is highly debated. This chapter
addresses this issue by taking another look at a specific case study which
reflects all the changes: the history of the dative alternation. To add to
results from earlier corpus-based investigations on this development, the
emergence of the alternation is modelled by means of Evolutionary Game
Theory (EGT). Specifically, the study tests the hypothesis that the increase
of prepositional ditransitives and ultimately the dative alternation is a
consequence of case marking being lost and constituent order becoming fixed,
and discusses the potential benefits of taking an EGT approach to such
questions.
Dialectal ditransitive patterns in British English
Authors: Gerwin Johanna , Röthlisberger Melanie
Published: July 2023

The present study weighs the effect of well-established
language-internal factors of the dative alternation such as animacy or
pronominality of the object phrases against language-external factors such
as origin of the speaker. For that purpose, the study samples three types of
dative variants (N = 7,070) from six regional dialects in
the UK, namely the canonical prepositional and double object constructions
as well as the alternative double object construction (e.g. Give it
me), using the Freiburg English Dialect Corpus (FRED) and the
British National Corpus (BNC). By applying a novel dialectometric approach
that uses conditional random forests, we compare the importance of
well-known predictors across these six regions and highlight two (political)
clusters that contrast England with Wales. Our study advances current
knowledge on regional variation in probabilistic grammars and highlights the
importance of including non-canonical variable patterns in the analysis.
Exploring variation in the dative alternation across World
Englishes
Authors: Röthlisberger Melanie
Published: July 2023

The present chapter explores the variable nature of speakers’
(probabilistic) grammar by analysing variation in the English dative
alternation across World Englishes. While the numerous constraints that
impact the choice of variant are well-known, the extent to which the
regional variability of these constraints in specific registers or lexical
items can be generalized to the language as a whole has largely remained
understudied (but see, e.g., Bresnan and
Ford 2010; Röthlisberger,
Grafmiller, and Szmrecsanyi 2017). The current study takes a
comprehensive large-scale comparative perspective across nine varieties, 14
different registers and including 86 alternating verbs
(N = 13,171) to showcase how restrictions in the dataset
(e.g. to specific registers or verbs) can result in misleading
generalizations. Results of mixed-effects regression analyses indicate that
the factors regionally variable across the whole dataset might not be
regionally variable across specific registers. Thus, the present chapter not
only confirms the variable nature of probabilistic grammars but also
stresses the importance of combining an aggregate perspective with more
fine-grained analyses to grasp more fully the cross-lectal variability of
speakers’ grammatical knowledge.
Ditransitives in Faroese
Authors: Ussery Cherlon , Petersen Hjalmar P.
Published: July 2023

This paper examines the acceptability of the double object and
prepositional frames for ditransitives in Faroese. We build on previous
literature which has discussed various factors which may influence speakers’
use of one frame over the other. We report the findings of a judgment study
in which we examined the degree to which semantic properties of verbs and
length of the indirect object affect speakers’ acceptability of each frame.
Our findings suggest that verbal semantics affect the acceptability of the
prepositional construction, but not the double object construction. Our
findings, however, do not directly support a heavy-late effect, unlike what
has been reported in previous literature on Faroese (most notably by Fiebig 2012).
The Complexity Principle and lexical complexity in the English and Dutch
dative alternation1
Authors: Dubois Tanguy
Published: July 2023

This study investigates the effects of lexical complexity on the
choice of dative alternants in English and Dutch. The lexical complexity of
a given word is operationalized as being proportional to how quickly
speakers can retrieve it from their mental lexicon, for which I consult the
databases of recent megastudies (Keuleers, Diependaele, and Brysbaert 2010: 1). Following the
Complexity Principle (Rohdenburg 1996), which states that cognitively
complex environments favour the grammatically more explicit variant in
linguistic alternations, it could be expected that lexically complex
environments favour prepositional datives. However, the models suggest that
speakers’ choices are not particularly sensitive to the complexity of larger
linguistic environments. Instead speakers aim to place the lexically
easier constituent before the more complex one. This turns out to be one of
the strongest predictors in both languages.
Giving in English and Norwegian
Authors: Egan Thomas
Published: July 2023

This chapter investigates ditransitive constructions and their
prepositional dative alternates, containing the cognate verbs English
give and Norwegian gi, using data from
the English–Norwegian Parallel Corpus (Johansson 2007). The bi-directional nature of the corpus enables
us not only to compare the distribution of constructions in the original
texts in the two languages but also to investigate how individual tokens are
translated into the other language. The analysis shows that give
constructions in the two languages are remarkably similar in their semantics
and their distribution. There are, however, some differences, including the
greater incidence of light verb constructions in English, and a tendency for
Norwegian translators to employ a get construction with the
recipient recoded as subject rather than indirect/prepositional
object.
Acquiring feature-based ordering preferences in English
ditransitives
Authors: Bürkle Daniel
Published: July 2023

The system of features affecting adults’ dative construction
choices in English is well established in recent research. Less is known
about how children might acquire this system. The two experiments in this
chapter add data to this question. They map out the effects of length,
animacy, and grammatical number on these choices in first language
acquisition. The first experiment combines an act-out task with eye-tracking
and finds that children as young as four years of age expect the
animate-before-inanimate order. The second experiment asks the same
participants to reproduce ditransitive sentences and finds that participants
reproduce sentences more easily if these conform to their ordering
preferences. These results suggest that the harmonic alignment evident in
dative ordering preferences is an epiphenomenon of cognitive ease.
Exit-hole repairing in 7475 aluminium alloy welded joints based on refill friction stir processing
Authors: Yuan Tao , Kang Shaoqian , Jiang Xiaoqing , Zhao Pengjing
Published: July 2023

In this study, the refill friction stir processing (RFSP) method was utilised to repair a exit-hole defect located at the end of the friction stir welding (FSW) joints in 7475 aluminium alloy plate. The morphology, macroscopic defects, and mechanical properties of the repaired joints were investigated. The results demonstrate that the exit-hole was successfully refilled after RFSP. Material flow caused the refill voids, annular grooves, and un-stirred material defects. The maximum strength reached 415 Mpa, equal to 105% of the base defect-free weld. The mechanical properties of repaired joint were largely influenced by the stir zone (SZ) boundary and un-stirred material defects.
A comprehensive review of modern engineered ceramics coatings for optimised resistance to wear and corrosion
Authors: Wolfe Douglas E. , Ryan Caillin J. , DeSalle Christopher M. , Stepanoff Sergei P. , Aronson Benjamin I. , Boring Zachary M. , Reiss Justin A. , Albert Patrick E. , Nicastro Jackson K. , Fjeldsted Aaron P.
Published: July 2023

The value and impact that ceramic coatings have had in the development of modern mechanical systems and protection of components exposed to harsh environments are often overlooked and understated. Modern equipment must be capable of withstanding substantial attrition, impact damage, erosion and corrosion that degrades materials across a variety of applications. Ceramic coatings enable a robust protective barrier for underlying substrates that outperforms most alternative film barrier materials (i.e. polymers, metals, glasses). In this work, a comprehensive review of modern ceramic coatings for barrier protection against mechanical wear and chemical attack is discussed in detail over a large breadth of relevant topics and case studies. This review highlights many critical aspects including various coating functionalities, design architectures, processing effects, material classes and promising future directions for engineering high-performance ceramic coating.
Paradoxical roles of caspase-3 in regulating cell survival, proliferation, and tumorigenesis
Authors: Eskandari Ebrahim , Eaves Connie J.
Published: July 2023

Caspase-3 is a widely expressed member of a conserved family of proteins, generally recognized for their activated proteolytic roles in the execution of apoptosis in cells responding to specific extrinsic or intrinsic inducers of this mode of cell death. However, accumulating evidence indicates that caspase-3 also plays key roles in regulating the growth and homeostatic maintenance of both normal and malignant cells and tissues in multicellular organisms. Given that yeast possess an ancestral caspase-like gene suggests that the caspase-3 protein may have acquired different functions later during evolution to better meet the needs of more complex multicellular organisms, but without necessarily losing all of the functions of its ancestral yeast precursor. This review provides an update on what has been learned about these interesting dichotomous roles of caspase-3, their evolution, and their potential relevance to malignant as well as normal cell biology.
Deep learning methods for partial differential equations and related parameter identification problems
Authors: Nganyu Tanyu Derick , Ning Jianfeng , Freudenberg Tom , Heilenkötter Nick , Rademacher Andreas , Iben Uwe , Maass Peter
Published: July 2023

Recent years have witnessed a growth in mathematics for deep learning—which seeks a deeper understanding of the concepts of deep learning with mathematics and explores how to make it more robust—and deep learning for mathematics, where deep learning algorithms are used to solve problems in mathematics. The latter has popularised the field of scientific machine learning where deep learning is applied to problems in scientific computing. Specifically, more and more neural network (NN) architectures have been developed to solve specific classes of partial differential equations (PDEs). Such methods exploit properties that are inherent to PDEs and thus solve the PDEs better than standard feed-forward NNs, recurrent NNs, or convolutional neural networks. This has had a great impact in the area of mathematical modelling where parametric PDEs are widely used to model most natural and physical processes arising in science and engineering. In this work, we review such methods as well as their extensions for parametric studies and for solving the related inverse problems. We also show their relevance in various industrial applications.
Computational simulations of spatio—temporal plasma dynamics in a very high frequency capacitively coupled reactor
Authors: Upadhyay Rochan R
Published: July 2023

The standing wave effect in Very High Frequency Capacitively Coupled Plasma (VHF CCP) reactors is a major cause of plasma non-uniformity. The nonlinearly excited higher harmonics exacerbate this non-uniformity. In this work we analyze the physical mechanisms of plasma—electromagnetic wave coupling in detail for a single RF cycle of the input electric field. We consider a simplified CCP reactor geometry operated at 100 mTorr and computationally simulate three cases where the bulk electron density increases from order 1015 m−3 to 1017 m−3. We see the appearance of higher harmonics in the B-dot signal with increasing bulk electron density in accordance with recent experimental measurements. By looking at the spatio-temporal variations of different quantities at a periodic steady state, we observe significant changes in the dynamics of current flow, electromagnetic power deposition and ionization rates within the reactor. In particular, as the electron density increases, we see that the current profile in the bulk plasma exhibits a re-circulation pattern that is correlated with the appearance of structural features in the B-dot signal seen in the measurements.
Spin torques and anomalous velocity in spin textures induced by fast electron injection from topological ferromagnets: The role of gauge fields
Authors: Bhattacharjee Satadeep , Lee Seung-Cheol
Published: July 2023

A new method for analyzing magnetization dynamics in spin textures under the influence of fast electron injection from topological ferromagnetic sources such as Dirac half metals has been proposed. These electrons, traveling at a velocity v with a non-negligible value of

v

/

c

(where c is the speed of light), generate a non-equilibrium magnetization density in the spin-texture region, which is related to an electric dipole moment via relativistic interactions. When this resulting dipole moment interacts with gauge fields in the spin-texture region, an effective field is created that produces spin torques. These torques, like spin-orbit torques that occur when electrons are injected from a heavy metal into a ferromagnet, can display both damping-like and anti-damping-like properties. Finally, we demonstrate that such an interaction between the dipole moment and the gauge field introduces an anomalous velocity that can contribute to transverse electrical conductivity in the spin texture in a way comparable to the topological Hall effect.
Coexistence of normal and inverse magnetocaloric effect in inhomogeneous Ni95Cr5 layers
Authors: Alman Vidya , Annadi Anil , Khan M A , Singh Vidyadhar , Bohra Murtaza
Published: July 2023

Understanding of the coexistence of normal and inverse magnetocaloric effects (MCE) makes it promising for use in magnetic cooling applications. This study discusses the selection of Ni95Cr5 layers and their expected magnetocaloric effects for an extended temperature range (200–800 K). These layers offer a wide range of suitable magnetic ordering temperatures as a function of thicknesses. A modified phenomenological model was used to estimate the entropy changes (

Δ

S

M

) and relative cooling power (RCP). Under adiabatic magnetic field variation, normal and inverse MCE are computed near the ferromagnetic-paramagnetic transition temperatures, T

C
and spin−glass transition temperatures, T

G
, respectively. Based on their

Δ

S

max

values (= −0.06 to 0.11 J kg−1-K−1) and RCP( = 7.6 to 15.5 J kg−1) at the smallest magnetic field of 0.5 kOe, which are comparable to other MCE layer materials. We provide evidence of a strong correlation between the change in magnetic anisotropy (measured in terms of MR/MS and HC) below T

G
, which subsequently leads to the reversal of

Δ

S

M

.

However, after annealing these effects somewhat vanish. The current study demonstrates that adjusting thickness, in addition to Cr doping, can externally regulate soft magnetic and magnetocaloric properties to create diverse magnetic ground states for future MCE and inverse MCE functionalities.
A Method of Superimposing Subapertures for Shark–Hartmann Wave Front Sensing with Faint Objects
Authors: Wu Xiaosong , Huang Linhai , Gu Naiting
Published: July 2023

For the astronomical adaptive optics systems, the observation condition is always in a regime of low photon flux. We present a method of superimposing subapertures for the Shark–Hartmann wave front sensing with faint objects. This approach significantly improves the signal-to-noise ratio (S/N) of the spot pattern by superimposing adjacent subapertures, thus circumventing the invalid wave front sensing with faint object, enhancing the accuracy of the wave front detection. In addition, we demonstrate that the validity of this approach is not an incidental result under a specific condition, which can be explained theoretically by exploiting the atmospheric turbulence model. Then we validate the approach with simulations and experimental realization under weak-light and bright-light conditions. Results show that the proposed subaperture superposition approach can achieve accurate wave front reconstruction for low S/N or faint object even in cases beyond the ability of conventional methods. It brings out a new idea, besides long exposure and variable sampling, that comes with a tradeoff between temporal sampling frequency and spatial resolution. In addition, this method is also valid for extended objects; we preliminarily validate this method on a 600 mm aperture solar telescope, achieving stable closed-loop control with lower-contrast objects.
1.7 μm all-fiber figure-9 mode-locked laser based on a fiber Bragg grating
Authors: Liu Yang , Zhang Peng , Fan Yunlong , Ning Yuzhu , He Shuang , Tong Shoufeng
Published: July 2023

Fiber lasers operating at 1.7 μm have very important applications in biomedicine, optical imaging, laser welding, optical communication and other fields because of their rich spectral characteristics in the near-infrared band. We designed and experimentally implemented a 1.7 μm all-fiber figure-9 (F9) mode-locked laser, with a fiber Bragg grating (FBG) acting as both the mirror and the spectrum filter. The all-fiber F9 design made the laser work in the mode-locking state more efficiently. We obtained mode-locked pulses with a central wavelength of 1724.76 nm and a repetition rate of 14.39 MHz when the pump power was 1.1 W, and the pulse width was about 54 ps. Limited by the bandwidth of the FBG, the 3 dB bandwidth of the mode-locked spectrum was about 0.18 nm. The output power was 52 mW at a pump power of 2.5 W. The multi-pulse dynamics were studied by adjusting the pump power and the polarization controllers, and pulse trains of up to six pulses in a group were achieved. The 1.7 μm narrow-bandwidth all-fiber F9 mode-locked laser is simple in structure and easy to build, with potential application as a seed source in high-energy ultrashort pulse lasers.
Solution of inverse problem for Gross-Pitaevskii equation with artificial neural networks
Authors: Pokatov S P , Ivanova T Yu , Ivanov D A
Published: July 2023

We propose an artificial neural network (ANN) design to solve the inverse problem for a 1D Gross–Pitaevskii equation (GPE). More precise, the ANN takes the squared modulus of the stationary GPE solution as an input and returns the parameters of the potential function and the factor in front of the GPE non-linear term. From the physical point of view the ANN predicts the parameters of a trap potential and the interaction constant of 1D Bose–Einstein condensate by its density distribution. Using the results of numerical solution of GPE for more than

30
000

sets of GPE parameters as train and validation datasets we build the ANN as a fast and accurate inverse GPE solver.
Electromagnetically induced grating in a nonlinear optomechanical cavity
Authors: Chen Fujun
Published: July 2023

We investigate theoretically the Fraunhofer diffraction pattern of the output field in a nonlinear optomechanical cavity with a degenerate optical parametric amplifier (OPA) and a higher order excited atomic ensemble. Studies show that the higher-order-excitation atom, which is similar to the degenerate OPA that acts as a nonlinear medium, induces an electromagnetically induced grating in the output spectrum of the probe field. The coherence of the mechanical oscillator leads to transfer of the probe energy in different diffraction orders of the probe field spectrum such that the phenomenon of optomechanically induced grating is generated from the output probe field. In particular, the presence of nonlinearities with the degenerate OPA and the higher order excited atoms can significantly affect the efficiency of the diffraction pattern providing an additional flexibility for controlling optical properties.
Restricted phase space thermodynamics of charged AdS black holes in conformal gravity*
Authors: Kong Xiangqing , Zhang Zhiqiang , Zhao Liu
Published: July 2023

The thermodynamics of charged spherically symmetric AdS black holes in conformal gravity is revisited using the recently proposed restricted phase space (RPS) formalism. This formalism avoids all the bizarreness arising in the extended phase space formalism for this model. It is found that the charged AdS black holes in this model may belong to a new universality class that is different from all previously studied cases under the RPS formalism. Besides the distinguished isocharge

and isothermal

behaviors, the absence of the Hawking-Page transition is another notable feature. However, in the high temperature limit, the thermodynamic behavior of the present model becomes exactly the same as that of the Einstein gravity and black hole scan models, which adds further evidence for the universality of the recently reported correspondence between high temperature AdS black holes and low temperature quantum phonon gases in nonmetallic crystals.
A numerical study to improve honey-comb topography designed for antifouling applications
Authors: Felicia Wong Yen Myan , Loh Kar Wei
Published: July 2023

Biofouling is a common issue faced by marine industry as having biofouling on the ship hulls increase unnecessary drag and friction which results in the increases of fuel consumption and decreases of cruising speed. Therefore, there are several antifouling approaches developed to mitigate the development of settlement of microorganism. The most environmentally friendly approach is surface modification by using foul-resistance topographies. The objective of this study is to investigate the antifouling performance based on the characteristics of the hydrodynamic variables which are the fluid velocity, wall shear stress, and shear strain rate at the surrounding of various designs of honeycomb topography surface. Three models were generated for this study which were Model 1 with an indented honeycomb structure surface, Model 2 with a protruded honeycomb structure surface, and Model 3 with a protruded honeycomb structure surface with different spacing and depth. The dimensions for Model 1 and Model 2 are the same whereas one is indenting while another one is protruding. In addition, Model 3 with different spacing and depth of protruded honeycomb structure was constructed to indicate the optimum design of honeycomb topography. The computer-aided design (CAD) model of the designs of honeycomb topography will be modelled using SolidWorks 2021. The CAD model will then be exported to ANSYS CFX simulator to determine the hydrodynamic variables of different designs of honeycomb topography. By analyzing the results of the simulation, the justification of the overall antifouling performance can be made and validated. The expected outcomes of this study would show a better antifouling performance of a protruding honeycomb topography design as compared to an indented honeycomb topography design. Other than that, the fluctuations in the hydrodynamic variables were higher for the protruded honeycomb structure model as the fluid is flow in the gaps between honeycomb structure instead of inside the honeycomb structure. Furthermore, the probability of fouling organisms being entrapped inside the honeycomb structure is eliminated by using the protruding honeycomb structure design. However, further research needs to be carried out as this study only focuses on the numerical method. The results obtained from this study can be used for future development on honeycomb topography design in antifouling applications, also helped to identify the optimum design of honeycomb topography that will improve the antifouling performance.
Drying of Artocarpus Heterophyllus and is application in treating dye wastewater
Authors: Alghaithi T , Ismail N , Chua B L
Published: July 2023

Coagulation is a common technique used in wastewater treatment plants to remove dissolved chemicals, turbidity, and colours. Aluminium sulphate (alum), the most common coagulant, has recently been connected to both Alzheimer’s disease and environmental issues. In order to deal with these issues, researchers are considering the possibility of developing a natural coagulant that is safe for both humans and the environment. In this research, Artocarpus Heterophyllus (Jackfruit) seeds were used to make a natural coagulant, and their use in the treatment of coloured wastewater was implemented. This study examined the effects of hot air-drying temperatures on the Jackfruit seed moisture content. Jackfruit seed application in dye wastewater treatment was also optimised via several experiments with varying coagulation parameters generated via central composite response surface design (CCD). Jackfruit seed drying and protein extraction are two crucial steps in making natural coagulants. Jackfruit seeds were dried in an oven at 40°C, 50 °C and 60°C to collect drying data. Drying information for the optimum air-drying temperature that produces the shortest drying time was used to generate five drying kinetic models. Based on the results of this research, 60°C hot air-drying temperature was chosen as the optimal drying temperature for Jackfruit seeds, resulting in the shortest total drying time of just 5 hours. Once the optimum hot air-drying temperature was recorded, five thin drying kinetic models were used to determine which module best explained the drying kinetics at the optimum hot air-drying temperature. Microsoft Excel solver was used to calculate the values of X2, R2, and RMSE. The kinetic model with the lowest X2 and RMSE was selected. The modified Midilli model was chosen as the best kinetic model for representing the drying performance of Jackfruit seeds, as it had the lowest X2 and RMSE. After that, the protein was extracted from jackfruit seeds that had been dried at 60°C for 5 hours. In order to extract the protein from jackfruit seeds, 2 g of dry seeds were dissolved in 100 mL of distilled water, blended, and filtered before being used in the Jar test. The initial concentration of dye wastewater, the pH of the wastewater, and the coagulant dosage were the main parameters in the jar test. Maximum colour removal of 85.81% was attained during Jackfruit seed-based dye wastewater treatment when the initial concentration of dye wastewater was 400 ppm; the coagulant dosage was 100mg/L, and the pH was 2. Therefore, these were chosen as the optimum parameters for treating dye wastewater with Jackfruit seeds.