bluuebunny/crossref_metadata_2025 huggingface dataset:
On the origin and evolution of hotspots in multipatterning processes
Authors: Panneerchelvam Prem , Huard Chad M. , Graves Trey , Pret Alessandro Vaglio , Gronheid Roel , Agarwal Ankur , Smith Mark D.
Published: June 2023

Understanding the origins and propagation of defects and hotspots in patterning processes used for semiconductor fabrication is of paramount importance in managing yield. In this paper, results from physics-based simulators to model lithography and dry etch processes are presented and compared to experimental results. These models are used to study different types of hotspots and defects observed in a litho-etch-litho-etch (LELE) multipatterning process. At each pass of the LELE flow, patterns are printed into a SiO2 collecting layer using a trilayer film stack comprised of a negative tone photoresist layer, a spin-on-glass layer (SOG), and a spin-on-carbon layer (SOC). After both passes of the LELE process, the patterns in the SiO2 collecting layer will be transferred to a TiN hardmask prior to final etch into an underlying dielectric. The SOG and SiO2 layers are etched using fluorocarbon plasma, while the SOC layer is etched with an H2/N2 plasma generated in a capacitively coupled plasma source. A pinching hotspot is observed during the single litho-etch pass in a region where two features are placed very close and the image contrast is low. However, for some lithography process conditions, this hotspot is rectified by subsequent etch steps and does not always transfer as a defect into the SiO2 layer. The quenching of the hotspot occurs primarily during the etching of the SOC layer due to the aspect ratio-dependent etching (ARDE) effect. A bridging hotspot is also observed at lithography during the single litho-etch pass at high exposure doses. This hotspot, on the other hand, is exacerbated by the etch steps because of the ARDE effect. Hotspots are also identified that originate from overlay errors between photomasks exposed during first and second passes of the LELE process. The etch bias generated during etching of the SOG layer is crucial to ensure that the overlay-related hotspot does not translate to the SiO2 layer. The extent of etch bias in the SOG etch step is critical and can be tuned by adjusting the neutral to ion flux ratio during that etch step. Increasing the flux ratio improves the process window for the overlay defect; however, when the ratio is higher than approximately 20% of the nominal value, a different defect type is formed in the SOG layer due to the inverse ARDE effect that propagates downstream to the SiO2 layer.
Effect of drift layer doping and NiO parameters in achieving 8.9 kV breakdown in 100 μm diameter and 4 kV/4 A in 1 mm diameter NiO/β-Ga2O3 rectifiers
Authors: Li Jian-Sian , Chiang Chao-Ching , Xia Xinyi , Wan Hsiao-Hsuan , Ren Fan , Pearton S. J.
Published: June 2023

The effect of doping in the drift layer and the thickness and extent of extension beyond the cathode contact of a NiO bilayer in vertical NiO/β-Ga2O3 rectifiers is reported. Decreasing the drift layer doping from 8 × 1015 to 6.7 × 1015 cm−3 produced an increase in reverse breakdown voltage (VB) from 7.7 to 8.9 kV, the highest reported to date for small diameter devices (100 μm). Increasing the bottom NiO layer from 10 to 20 nm did not affect the forward current–voltage characteristics but did reduce reverse leakage current for wider guard rings and reduced the reverse recovery switching time. The NiO extension beyond the cathode metal to form guard rings had only a slight effect (∼5%) in reverse breakdown voltage. The use of NiO to form a pn heterojunction made a huge improvement in VB compared to conventional Schottky rectifiers, where the breakdown voltage was ∼1 kV. The on-state resistance (RON) was increased from 7.1 m Ω cm2 in Schottky rectifiers fabricated on the same wafer to 7.9 m Ω cm2 in heterojunctions. The maximum power figure of merit (VB)2/RON was 10.2 GW cm−2 for the 100 μm NiO/Ga2O3 devices. We also fabricated large area (1 mm2) devices on the same wafer, achieving VB of 4 kV and 4.1 A forward current. The figure-of-merit was 9 GW  cm−2 for these devices. These parameters are the highest reported for large area Ga2O3 rectifiers. Both the small area and large area devices have performance exceeding the unipolar power device performance of both SiC and GaN.
“Be a Good Fan During the Good, the Bad, and Even the Ugly”: Exploring Cultural Boundaries Through Sport Fan Discourses on Twitter
Authors: Sveinson Katherine , Hoeber Larena
Published: June 2023

While sport fandom can be assumed to be inclusive, a deeper exploration of discourses around fandom exposes alternative perspectives. Using the frameworks of cultural boundaries and critical discourse studies, we explored how sport fans use Twitter to create, maintain, and transform cultural boundaries of sport fandom. We used tweets from a season of the Toronto Blue Jays baseball team as a case. Data were collected via Visual Twitter Analytics software focusing on tweets containing #LetsRise and #BlueJays. From the larger data set, we selected 172 tweets to examine using critical discourse analysis and ideological structures of discourse. Findings demonstrate that discourses of loyalty, consumption, and unity have plural meanings and are used to draw boundaries that are simultaneously fluid and rigid. Thus, we argue that fans engage in an active process of determining who is and is not included in fan cultures through Twitter use.
A Review and Research Agenda for Brand Communities in Sports
Authors: Wagner David
Published: June 2023

Research on brand communities has burgeoned over the past 2 decades. Today many, if not most, sport organizations are entertaining dedicated brand communities. This article traces the development of community thinking in the field of sport management and marketing. Key articles on brand communities in leading journals in the field are identified, reviewed, and their core contributions distilled. By drawing on literature from adjacent fields, seven areas of future research are proposed: make or buy community, getting value from community, building a community capability, solving the community engagement puzzle, focusing on effective community engagement practices, analyzing the full community life cycle, and community for Web 3.0. The article provides a number of recommendations for future research on brand communities in sport management and marketing, enabling scholars to advance knowledge for both research and practice.
The Use of Social Media in Sport Doping Enforcement and Control
Authors: Fischer Kerry , Birren Genevieve F.E.
Published: June 2023

The increased prevalence of social media in organizational communication suggests that it is only a matter of time before it is used in sport doping prevention and control. This commentary intends to highlight not only how antidoping organizations and individual athletes are using social media to promote awareness to clean sport competition but also how the relationship between social media and various sport stakeholders may develop in the future. In particular, it focuses on three main areas in the intersection of social media and doping prevention: agenda-setting by antidoping organizations via formal social media campaigns, social norm control by athletes when they post on social media, and social media use by athletes and fans as a form of framing. Prospective research directions, as well as probable future uses of social media in doping enforcement and control, are also discussed, including using social media to monitor athlete whereabouts and to communicate directly with athletes in doping matters.
The E3 ligase HERC5 promotes antimycobacterial responses in macrophages by ISGylating the phosphatase PTEN
Authors: Du Xialin , Sheng Junli , Chen Yitian , He Shitong , Yang Yalong , Huang Yulan , Fu Yuling , Lie Linmiao , Han Zhenyu , Zhu Bo , Liu Honglin , Wen Qian , Zhou Xinying , Zhou Chaoying , Hu Shengfeng , Ma Li
Published: June 2023

Innate immune signaling in macrophages during viral infection is regulated by ISGylation, the covalent attachment of the ubiquitin-like protein interferon-stimulated gene 15 (ISG15) to protein targets. Here, we explored the role of ISGylation in the macrophage response to infection with
Mycobacterium tuberculosis
. In human and mouse macrophages, the E3 ubiquitin ligases HERC5 and mHERC6, respectively, mediated the ISGylation of the phosphatase PTEN, which promoted its degradation. The decreased abundance of PTEN led to an increase in the activity of the PI3K-AKT signaling pathway, which stimulated the synthesis of proinflammatory cytokines. Bacterial growth was increased in culture and in vivo when human or mouse macrophages were deficient in the major E3 ISG15 ligase. The findings expand the role of ISGylation in macrophages to antibacterial immunity and suggest that HERC5 signaling may be a candidate target for adjunct host-directed therapy in patients with tuberculosis.
Cation flux through SUR1-TRPM4 and NCX1 in astrocyte endfeet induces water influx through AQP4 and brain swelling after ischemic stroke
Authors: Stokum Jesse A. , Shim Bosung , Negoita Serban , Tsymbalyuk Natalya , Tsymbalyuk Orest , Ivanova Svetlana , Keledjian Kaspar , Bryan Joseph , Blaustein Mordecai P. , Jha Ruchira M. , Kahle Kristopher T. , Gerzanich Volodymyr , Simard J. Marc
Published: June 2023

Brain swelling causes morbidity and mortality in various brain injuries and diseases but lacks effective treatments. Brain swelling is linked to the influx of water into perivascular astrocytes through channels called aquaporins. Water accumulation in astrocytes increases their volume, which contributes to brain swelling. Using a mouse model of severe ischemic stroke, we identified a potentially targetable mechanism that promoted the cell surface localization of aquaporin 4 (AQP4) in perivascular astrocytic endfeet, which completely ensheathe the brain’s capillaries. Cerebral ischemia increased the abundance of the heteromeric cation channel SUR1-TRPM4 and of the Na
+
/Ca
2+
exchanger NCX1 in the endfeet of perivascular astrocytes. The influx of Na
+
through SUR1-TRPM4 induced Ca
2+
transport into cells through NCX1 operating in reverse mode, thus raising the intra-endfoot concentration of Ca
2+
. This increase in Ca
2+
stimulated calmodulin-dependent translocation of AQP4 to the plasma membrane and water influx, which led to cellular edema and brain swelling. Pharmacological inhibition or astrocyte-specific deletion of SUR1-TRPM4 or NCX1 reduced brain swelling and improved neurological function in mice to a similar extent as an AQP4 inhibitor and was independent of infarct size. Thus, channels in astrocyte endfeet could be targeted to reduce postischemic brain swelling in stroke patients.
NhaR, LeuO, and H-NS Are Part of an Expanded Regulatory Network for Ectoine Biosynthesis Expression
Authors: Boas Lichty Katherine E. , Gregory Gwendolyn J. , Boyd E. Fidelma
Published: June 2023

Ectoine is a commercially used compatible solute that acts as a biomolecule stabilizer because of its additional role as a chemical chaperone. A better understanding of how the ectoine biosynthetic pathway is regulated in natural bacterial producers can be used to increase efficient industrial production.
IFNλ: balancing the light and dark side in pulmonary infection
Authors: Antos Danielle , Alcorn John F.
Published: June 2023

Interferon (IFN) represents a well-known component of antiviral immunity that has been studied extensively for its mechanisms of action and therapeutic potential when antiviral treatment options are limited. Specifically in the respiratory tract, IFNs are induced directly on viral recognition to limit the spread and transmission of the virus. Recent focus has been on the IFNλ family, which has become an exciting focus in recent years for its potent antiviral and anti-inflammatory activities against viruses infecting barrier sites, including the respiratory tract. However, insights into the interplay between IFNλs and other pulmonary infections are more limited and suggest a more complex role, potentially detrimental, than what was seen during viral infections. Here, we review the role of IFNλs in pulmonary infections, including viral, bacterial, fungal, and multi-pathogen super-infections, and how this may impact future work in the field.
Elucidation of independently modulated genes in
Streptococcus pyogenes
reveals carbon sources that control its expression of hemolytic toxins
Authors: Hirose Yujiro , Poudel Saugat , Sastry Anand V. , Rychel Kevin , Lamoureux Cameron R. , Szubin Richard , Zielinski Daniel C. , Lim Hyun Gyu , Menon Nitasha D. , Bergsten Helena , Uchiyama Satoshi , Hanada Tomoki , Kawabata Shigetada , Palsson Bernhard O. , Nizet Victor
Published: June 2023

Streptococcus pyogenes
can cause a wide variety of acute infections throughout the body of its human host. An underlying transcriptional regulatory network (TRN) is responsible for altering the physiological state of the bacterium to adapt to each unique host environment. Consequently, an in-depth understanding of the comprehensive dynamics of the
S. pyogenes
TRN could inform new therapeutic strategies. Here, we compiled 116 existing high-quality RNA sequencing data sets of invasive
S. pyogenes
serotype M1 and estimated the TRN structure in a top-down fashion by performing independent component analysis (ICA). The algorithm computed 42 independently modulated sets of genes (iModulons). Four iModulons contained the
nga-ifs-slo
virulence-related operon, which allowed us to identify carbon sources that control its expression. In particular, dextrin utilization upregulated the
nga-ifs-slo
operon by activation of two-component regulatory system CovRS-related iModulons, altering bacterial hemolytic activity compared to glucose or maltose utilization. Finally, we show that the iModulon-based TRN structure can be used to simplify the interpretation of noisy bacterial transcriptome data at the infection site.

IMPORTANCE

S. pyogenes
is a pre-eminent human bacterial pathogen that causes a wide variety of acute infections throughout the body of its host. Understanding the comprehensive dynamics of its TRN could inform new therapeutic strategies. Since at least 43
S
.
pyogenes
transcriptional regulators are known, it is often difficult to interpret transcriptomic data from regulon annotations. This study shows the novel ICA-based framework to elucidate the underlying regulatory structure of
S. pyogenes
allows us to interpret the transcriptome profile using data-driven regulons (iModulons). Additionally, the observations of the iModulon architecture lead us to identify the multiple regulatory inputs governing the expression of a virulence-related operon. The iModulons identified in this study serve as a powerful guidepost to further our understanding of
S. pyogenes
TRN structure and dynamics.
When does a Lotka-Volterra model represent microbial interactions? Insights from
in vitro
nasal bacterial communities
Authors: Dedrick Sandra , Warrier Vaishnavi , Lemon Katherine P. , Momeni Babak
Published: June 2023

To alter microbial community composition for therapeutic purposes, an accurate and reliable modeling framework capable of predicting microbial community outcomes is required. Lotka-Volterra (LV) equations have been utilized to describe a breadth of microbial communities, yet, the conditions in which this modeling framework is successful remain unclear. Here, we propose that a set of simple
in vitro
experiments—growing each member in cell-free spent medium obtained from other members—can be used as a test to decide whether an LV model is appropriate for describing microbial interactions of interest. We show that for LV to be a good candidate, the ratio of growth rate to carrying capacity of each isolate when grown in the cell-free spent media of other isolates should remain constant. Using an
in vitro
community of human nasal bacteria as a tractable system, we find that LV can be a good approximation when the environment is low-nutrient (i.e., when growth is limited by the availability of nutrients) and complex (i.e., when multiple resources, rather than a few, determine growth). These findings can help clarify the range of applicability of LV models and reveal when a more complex model may be necessary for predictive modeling of microbial communities.

IMPORTANCE

Although mathematical modeling can be a powerful tool to draw useful insights in microbial ecology, it is crucial to know when a simplified model adequately represents the interactions of interest. Here, we take advantage of bacterial isolates from the human nasal passages as a tractable model system and conclude that the commonly used Lotka-Volterra model can represent interactions among microbes well when the environment is complex (with many interaction mediators) and low-nutrient. Our work highlights the importance of considering both realism and simplicity when choosing a model to represent microbial interactions.
Supplemental Material: Three-dimensional glacial isostatic adjustment modeling reconciles conflicting geographic trends in North American marine isotope stage 5a relative sea level observations
Authors: Thompson Schmitty B. , al. et
Published: June 2023

Table S1: North American and Caribbean Marine Isotope Stage 5a and 5e sea level indicator data. Figures S1 and S2 on the sensitivity of model predictions to ice margin geometry and plate boundary thickness. 
Kangaroo mother care for preterm or low birth weight infants: a systematic review and meta-analysis
Authors: Sivanandan Sindhu , Sankar Mari Jeeva
Published: June 2023

Importance

The Cochrane review (2016) on kangaroo mother care (KMC) demonstrated a significant reduction in the risk of mortality in low birth weight infants. New evidence from large multi-centre randomised trials has been available since its publication.

Objective

Our systematic review compared the effects of KMC vs conventional care and early (ie, within 24 hours of birth) vs late initiation of KMC on critical outcomes such as neonatal mortality.

Methods

Eight electronic databases, including PubMed®, Embase, and Cochrane CENTRAL, from inception until March 2022, were searched. All randomised trials comparing KMC vs conventional care or early vs late initiation of KMC in low birth weight or preterm infants were included.

Data extraction and synthesis

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered with PROSPERO.

Main outcomes and measures

The primary outcome was mortality during birth hospitalization or 28 days of life. Other outcomes included severe infection, hypothermia, exclusive breastfeeding rates, and neurodevelopmental impairment. Results were pooled using fixed-effect and random-effects meta-analyses in RevMan 5.4 and Stata 15.1 (StataCorp, College Station, TX).

Results

In total, 31 trials with 15 559 infants were included in the review; 27 studies compared KMC with conventional care, while four compared early vs late initiation of KMC. Compared with conventional care, KMC reduces the risks of mortality (relative risk (RR) 0.68; 95% confidence interval (CI) 0.53 to 0.86; 11 trials, 10 505 infants; high certainty evidence) during birth hospitalisation or 28 days of age and probably reduces severe infection until the latest follow-up (RR 0.85, 95% CI 0.79 to 0.92; nine trials; moderate certainty evidence). On subgroup analysis, the reduction in mortality was noted irrespective of gestational age or weight at enrolment, time of initiation, and place of initiation of KMC (hospital or community); the mortality benefits were greater when the daily duration of KMC was at least 8 hours per day than with shorter-duration KMC. Studies comparing early vs late-initiated KMC demonstrated a reduction in neonatal mortality (RR 0.77, 95% CI 0.66 to 0.91; three trials, 3693 infants; high certainty evidence) and a probable decrease in clinical sepsis until 28-days (RR 0.85, 95% CI 0.76 to 0.96; two trials; low certainty evidence) following early initiation of KMC.

Conclusions and relevance

The review provides updated evidence on the effects of KMC on mortality and other critical outcomes in preterm and low birth weight infants. The findings suggest that KMC should preferably be initiated within 24 hours of birth and provided for at least 8 hours daily.
A hybrid SVR-BO model for predicting the soil thermal conductivity with uncertainty
Authors: Li Kai-Qi , Yin Zhen-Yu , Liu Yong
Published: June 2023

This study proposes a generalised framework for developing a hybrid machine learning (ML) model that combines support vector regression (SVR) with hyperparameter optimisation to predict thermal conductivity ( k) with uncertainty. The framework contains four phases: data pre-processing, determining the best-performing hybrid model, selecting the optimal input combination, and uncertainty implementation. A database containing 2197 data points is first compiled to train the ML model. Three hyperparameter optimisation algorithms are adopted to tune hyperparameters, and their performance is evaluated by model evaluation metrics. Results show that SVR with Bayesian optimisation (SVR-BO) is the best-performing model since it produces more accurate predictions for k than models that employ grid and random searches. Given the sample insufficiency issue encountered in practice, the SVR-BO models with 144 input combinations are analysed. The compassion among models under various input combinations indicates that incorporating temperature as an additional input can provide moderate improvement in the accuracy and generalisability of the hybrid model. Based on the comparison, a five-input model is selected as the best candidate to implement the uncertainty evaluation for k. Results demonstrate that the predicted k possesses higher reliability for denser datasets and shows promising potential for applications in k with uncertainty assessments.
A high-resolution pixel silicon Vertex Detector for open charm measurements with the NA61/SHINE spectrometer at the CERN SPS
Authors: Aduszkiewicz A. , Bajda M. , Baszczyk M. , Bryliíski W. , Brzychczyk J. , Deveaux M. , Dorosz P. , Luise S. Di , Feofilov G. , Gazdzicki M. , Igolkin S. , Jabłoński M. , Kovalenko V. , Koziel M. , Kucewicz W. , Larsen D. , Lazareva T. , Majka Z. , Martinengo P. , Merzlaya A. , Mik L. , Płaneta R. , Staszel P. , Suljic M. , Tefelski D. , Vechernin V.
Published: June 2023

The study of open charm meson production provides an efficient tool for the investigation of the properties of hot and dense matter formed in nucleus–nucleus collisions. The interpretation of the existing di-muon data from the CERN SPS suffers from a lack of knowledge on the mechanism and properties of the open charm particle production. Due to this, the heavy-ion programme of the NA61/SHINE experiment at the CERN SPS has been extended by precise measurements of charm hadrons with short lifetimes. A new Vertex Detector for measurements of the rare processes of open charm production in nucleus–nucleus collisions was designed to meet the challenges of track registration and high resolution in primary and secondary vertex reconstruction. A small-acceptance version of the vertex detector was installed in 2016 and tested with Pb + Pb collisions at 150$$A\,\text{ GeV }\!/\!c$$

A

GeV

/

c

. It was also operating during the physics data taking on Xe + La and Pb + Pb collisions at 150$$A\,\text{ GeV }\!/\!c$$

A

GeV

/

c

conducted in 2017 and 2018. This paper presents the detector design and construction, data calibration, event reconstruction, and analysis procedure.
Aspects of cubic nilpotent superfields
Authors: Aldabergenov Yermek , Antoniadis Ignatios , Chatrabhuti Auttakit , Isono Hiroshi
Published: June 2023

We study in more detail the cubic constraints for $${\mathcal N}=1$$

N
=
1

chiral superfields proposed in the earlier work Eur. Phys. J. C 81, 523 (2021), which describe low-energy goldstino-axion dynamics in global non-linearly realized supersymmetry. We generalize the constraint (i) by gauging the abelian symmetry that shifts the axion, and (ii) to supergravity. In the former case we show that after adding the abelian gauge multiplet, the construction can be formulated as a cubic nilpotent massive vector superfield. In the latter case we find explicit solution to the constraint including contributions from the supergravity multiplet. We also propose microscopic supergravity models (with linear supersymmetry), including a toy model for the string dilaton, which give rise to the cubic constraints at low energies.
Existence of horizontal immersions in fat distributions
Authors: Bhowmick Aritra , Datta Mahuya
Published: June 2023

Contact structures, as well as their holomorphic and quaternionic counterparts, are the primary examples of strongly bracket generating (or fat) distributions. In this paper, we associate a numerical invariant to corank-[Formula: see text] fat distribution on manifolds, referred to as the degree of the distribution. The real distribution underlying a holomorphic contact structure is of degree [Formula: see text]. Using Gromov’s sheaf theoretic and analytic techniques of [Formula: see text]-principle, we prove the existence of horizontal immersions of an arbitrary manifold into degree [Formula: see text] fat distributions and the quaternionic contact structures. We also study isocontact immersions, i.e. immersions that pull back a fat distribution to a given contact structure.
Compactness theorems for Yang–Mills–Higgs fields
Authors: Wang Guanxiang
Published: June 2023

In this paper, we obtain compactness theorems for Yang–Mills–Higgs fields on vector bundle [Formula: see text] over compact Riemannian manifold [Formula: see text], [Formula: see text], with general Higgs-like potential [Formula: see text].
Virtual Machine and Integrated Developer Environment for Sleptsov Net Computing
Authors: Zaitsev Dmitry A. , Shmeleva Tatiana R. , Zhang Qing , Zhao Hongfei
Published: June 2023

Modern computing is a path of violations and transformations coming from an intrinsically concurrent application domain into a sequence of instructions and then back to concurrency with OpenMP, MPI and CUDA/OpenCL. Why we create so many difficulties? Sleptsov Net Computing (SNC) maps a task into an appropriate computing structure implemented as a re-configurable multidimensional sparse matrix of computing memory. It has entirely graphical mass parallel language for concurrent programming and a framework of techniques for concurrent program verification to develop reliable software. Estimated efficiency of SNC is higher than 50% compared to actual less that 1% efficiency of the most powerful supercomputers. It yields hyper-performance capable of efficient control of hyper-sonic objects, colliders, thermonuclear reaction. This paper presents an open source prototype VM and IDE for SNC with a view on upcoming hardware implementation of the corresponding computer.
A Novel Image Recovery from Moving Water Surface Using Multi-Objective Bispectrum Method
Authors: Kumar Kattela Pavan , Rao Matcha Venu Gopala , Venkatanarayana Moram
Published: June 2023

Nowadays, the image degradation field suffers from several challenges while processing underwater color images including color distortion and image blurring due to the scattering media. Moreover, to get appropriate multi-frame super-resolution images, there is essential for recovering a better quantity of images. Traditionally, the shift among images is directly evaluated when considering the under-sampled Low-Resolution (LR) images. On the other hand, the high-frequency LR image faces unreliability owing to the aliasing consequences of sub-sampling, but it will also degrade the recovery accuracy. This task design implements a novel image recovery model from the moving water surface by adopting the multi-objective adaptive higher-order spectral analysis. Image pre-processing, lucky region selection, and image recovery are the three main phases of this model. The bicoherence method and dice coefficient method are adopted for performing the lucky region selection. Finally, the adoption of the multi-objective adaptive bispectra method is used for performing the image recovery from the moving water surface. The improved Adaptive Fitness-oriented Random number-based Galactic Swarm Optimization (AFR-GSO) algorithm is used for optimizing the constraints of the bispectrum method. The experimental results verify the enrichment of image quality by the proposed model over the existing techniques.
Unifying Radford’s biproducts over Hopf braces
Authors: Guo Qiaoling , Zhu Haixing
Published: June 2023

Let [Formula: see text] be a braided Hopf brace, i.e. a Hopf brace in the category of Yetter–Drinfeld modules over a Hopf brace [Formula: see text]. In this note, we give the sufficient and necessary conditions which make Radford’s biproduct [Formula: see text] and [Formula: see text] become a Hopf brace.
Energy–momentum tensor: Noether vs Hilbert
Authors: Itin Yakov
Published: June 2023

Several definitions of the energy–momentum tensor in classical field models on differential manifolds are examined in this work. We specifically talk about the connection between - Hilbert’s symmetric and Noether’s asymmetric energy–momentum tensors. We consider a matter field Lagrangian on a manifold endowed with a teleparallel (coframe) structure. The associated 3-form of coframe conserved current can be viewed as a link between Noether’s and Hilbert’s energy–momentum tensors. In these circumstances, we are able to show the complete equivalence of Hilbert’s and Noether’s currents for the matter field.
CT Images Segmentation Using a Deep Learning-Based Approach for Preoperative Projection of Human Organ Model Using Augmented Reality Technology
Authors: Elloumi Nessrine , Ben Makhlouf Aicha , Afli Ayman , Louhichi Borhen , Jaidane Mehdi , Tavares João Manuel R. S.
Published: June 2023

Over the last decades, facing the blooming growth of technological progress, interest in digital devices such as computed tomography (CT) as well as magnetic resource imaging which emerged in the 1970s has continued to grow. Such medical data can be invested in numerous visual recognition applications. In this context, these data may be segmented to generate a precise 3D representation of an organ that may be visualized and manipulated to aid surgeons during surgical interventions. Notably, the segmentation process is performed manually through the use of image processing software. Within this framework, multiple outstanding approaches were elaborated. However, the latter proved to be inefficient and required human intervention to opt for the segmentation area appropriately. Over the last few years, automatic methods which are based on deep learning approaches have outperformed the state-of-the-art segmentation approaches due to the use of the relying on Convolutional Neural Networks. In this paper, a segmentation of preoperative patients CT scans based on deep learning architecture was carried out to determine the target organ’s shape. As a result, the segmented 2D CT images are used to generate the patient-specific biomechanical 3D model. To assess the efficiency and reliability of the proposed approach, the 3DIRCADb dataset was invested. The segmentation results were obtained through the implementation of a U-net architecture with good accuracy.
Dielectric Properties of a Phenanthrene-Like Nanoisland B14A10: Monte Carlo Study
Authors: Fadil Z. , Raorane Chaitany Jayprakash , Fdil R.-El , Kim Seong Cheol
Published: June 2023

The dielectric properties of a monolayer phenanthrene-like nanoisland of formula B[Formula: see text]A[Formula: see text] are examined in this research using Monte Carlo simulations. We evaluate the behaviors of the electric hysteresis loops and blocking temperature under the exchange coupling, crystalline field and temperature effects. The multi-loop hysteresis behavior examined in this research may have beneficial applications in nanotechnology and multi-state memory storage. Besides, the results found in the Phenanthrene-like nanoisland are in good agreement with several theoretical and experimental results.
Thermo-hydro-mechanical nonlocal response on porous deep-sea sediments under vibration of mining vehicle
Authors: Sur Abhik
Published: June 2023

The excessive deformation of deep-sea sediments caused by the vibration of the mining machine will adversely affect the efficiency and safety of mining. This paper reports the study of coupled thermo-hydro-mechanical problem for saturated porous deep-sea sediments, subjected to the vibration of the mining vehicle. Based on nonlocal Moore–Gibson–Thompson thermoelastic theory and Darcy’s law, the model for thermo-hydro-mechanical dynamic response for saturated porous deep-sea sediments under the vibration of mining vehicle is established. Analytical solutions for vertical displacement, excess pore water pressure, vertical stress, temperature and the change in the volume fraction field have been obtained on implementing the normal mode analysis, and the numerical results have been depicted graphically. The result provides the direction on how the vibration frequency and the loading amplitude can affect the physical quantities of the foundation of the seabed. The influence of nonlocality and memory effect on the seabed is also reported.
Early Neoproterozoic magmatism and Caledonian metamorphism recorded by the Mårma terrane, Seve Nappe Complex, northern Swedish Caledonides
Authors: Callegari Riccardo , Kośmińska Karolina , Barnes Christopher J. , Klonowska Iwona , Barker Abigail K. , Rousku Sabine , Nääs Erika , Kooijman Ellen , Witt-Nilsson Patrik , Majka Jarosław
Published: June 2023

Petrology, geochronology and bulk-rock chemistry are combined to investigate the early Neoproterozoic magmatism and Cambrian–Ordovician metamorphism in the northern Swedish Caledonides. This work includes several lithologies of the Mårma terrane in the Seve Nappe Complex exposed in the Kebnekaise region. U–Pb zircon geochronology yielded crystallization ages of 835 ± 8 Ma for a mylonitic orthogneiss, 864 ± 3 Ma for the Vistas Granite and 840 ± 7 Ma for an intruded granitic dyke, whereas a gabbro and a granodiorite intrusion gave U–Pb zircon crystallization ages of 856 ± 3 Ma and 850 ± 1 Ma, respectively. U–Pb monazite dating of the mylonitic orthogneiss gave an upper intercept age of 841 ± 7 Ma and a lower intercept age of 443 ± 20 Ma. Pressure–temperature estimates derived for the mylonitic orthogneiss reveal metamorphic peak-pressure and peak-temperature of 10.5–11.75 kbar and 550–610°C and 7.4–8.1 kbar at 615–675°C, respectively. Metamorphic pressure–temperature estimates for the Vistas Granite yield 6.5–7.5 kbar at 600–625°C. Whole-rock chemistry coupled with U–Pb geochronology indicates that bimodal magmatism was related to attempted rifting of Rodinia between 870 and 840 Ma.

Supplementary material:
Supplementary figures and tables are available at
https://doi.org/10.6084/m9.figshare.c.6675075

Thematic collection:
This article is part of the Caledonian Wilson cycle collection available at:
https://www.lyellcollection.org/topic/collections/the-caledonian-wilson-cycle
Tectonic evolution of a Paleoproterozoic diffuse cryptic suture zone in northern Fennoscandia and the correlation of northern Fennoscandia and southern Greenland
Authors: Lahtinen Raimo , Köykkä Juha , Kurhila Matti
Published: June 2023

The boundary between the Karelia and Norrbotten continental blocks in Fennoscandia is a diffuse cryptic suture zone recording
c.
200 Ma of tectono-metamorphic evolution between 1.92 and 1.72 Ga. Syn-collisional deposition at 1.92–1.91 Ga was followed by post-collisional deposition at 1.88–1.87 and 1.85–1.84 Ga. The post-collision structural overprint in the suture starts with sinistral movements due to aulacogen inversion (D2) east of the suture. Late-D2 and
D
orocline
extensional stages are followed by NE-vergent basin inversion (D3) of <1.88 Ga rocks and transpressional dextral shear in the suture zone. Nearly orthogonal D4 and D5 deformation events overprint earlier fabrics at
c.
1.83 and
c.
1.78 Ga, respectively. The youngest (D6,
c.
1.73 Ga) structures include sinistral brittle–ductile movements. Northern Fennoscandia and southern Greenland are linked by coeval continent–continent collisions (D1, 1.92–1.89 Ga). The
D
orocline
stage (
c.
1.87 Ga), responsible for oroclinal buckling in central Fennoscandia, is conceivably related to west-directed subduction and subsequent regional shortening in western Greenland. The D3–D4 events in Fennoscandia are comparable to, and the D5–D6 events correlate well with, tectonic events in the suture zone in the eastern Nagssugtoqidian orogen in Greenland.

Supplementary material:
Analytical methods, data, interpretations of U–Pb data, and structural data on detailed study areas and key locations are available at
https://doi.org/10.6084/m9.figshare.c.6675191
Formally Verified Samplers from Probabilistic Programs with Loops and Conditioning
Authors: Bagnall Alexander , Stewart Gordon , Banerjee Anindya
Published: June 2023

We present Zar: a formally verified compiler pipeline from discrete probabilistic programs with unbounded loops in the conditional probabilistic guarded command language (cpGCL) to proved-correct executable samplers in the random bit model. We exploit the key idea that all discrete probability distributions can be reduced to unbiased coin-flipping schemes. The compiler pipeline first translates cpGCL programs into choice-fix trees, an intermediate representation suitable for reduction of biased probabilistic choices. Choice-fix trees are then translated to coinductive interaction trees for execution within the random bit model. The correctness of the composed translations establishes the sampling equidistribution theorem: compiled samplers are correct wrt. the conditional weakest pre-expectation semantics of cpGCL source programs. Zar is implemented and fully verified in the Coq proof assistant. We extract verified samplers to OCaml and Python and empirically validate them on a number of illustrative examples.
Mostly Automated Proof Repair for Verified Libraries
Authors: Gopinathan Kiran , Keoliya Mayank , Sergey Ilya
Published: June 2023

The cost of maintaining formally specified and verified software is widely considered prohibitively high due to the need to constantly keep code and the proofs of its correctness in sync—the problem known as
proof repair
. One of the main challenges in automated proof repair for evolving code is to infer invariants for a new version of a once verified program that are strong enough to establish its full functional correctness.

In this work, we present the first proof repair methodology for higher-order imperative functions, whose initial versions were verified in the Coq proof assistant and whose specifications remained unchanged. Our proof repair procedure is based on the combination of dynamic program alignment, enumerative invariant synthesis, and a novel technique for efficiently pruning the space of invariant candidates, dubbed
proof-driven testing
, enabled by the constructive nature of Coq’s proof certificates.

We have implemented our approach in a mostly-automated proof repair tool called Sisyphus. Given an OCaml function verified in Coq and its unverified new version, Sisyphus produces a Coq proof for the new version, discharging most of the new proof goals automatically and suggesting high-confidence obligations for the programmer to prove for the cases when automation fails. We have evaluated Sisyphus on 10 OCaml programs taken from popular libraries, that manipulate arrays and mutable data structures, considering their verified original and unverified evolved versions. Sisyphus has managed to repair proofs for all those functions, suggesting correct invariants and generating a small number of easy-to-prove residual obligations.
WasmRef-Isabelle: A Verified Monadic Interpreter and Industrial Fuzzing Oracle for WebAssembly
Authors: Watt Conrad , Trela Maja , Lammich Peter , Märkl Florian
Published: June 2023

We present WasmRef-Isabelle, a monadic interpreter for WebAssembly written in Isabelle/HOL and proven correct with respect to the WasmCert-Isabelle mechanisation of WebAssembly. WasmRef-Isabelle has been adopted and deployed as a fuzzing oracle in the continuous integration infrastructure of Wasmtime, a widely used WebAssembly implementation. Previous efforts to fuzz Wasmtime against WebAssembly's official OCaml reference interpreter were abandoned by Wasmtime's developers after the reference interpreter exhibited unacceptable performance characteristics, which its maintainers decided not to fix in order to preserve the interpreter's close definitional correspondence with the official specification. With WasmRef-Isabelle, we achieve the best of both worlds - an interpreter fast enough to be useable as a fuzzing oracle that also maintains a close correspondence with the specification through a mechanised proof of correctness.

We verify the correctness of WasmRef-Isabelle through a two-step refinement proof in Isabelle/HOL. We demonstrate that WasmRef-Isabelle significantly outperforms the official reference interpreter, has performance comparable to a Rust debug build of the industry WebAssembly interpreter Wasmi, and competes with unverified oracles on fuzzing throughput when deployed in Wasmtime's fuzzing infrastructure. We also present several new extensions to WasmCert-Isabelle which enhance WasmRef-Isabelle's utility as a fuzzing oracle: we add support for a number of upcoming WebAssembly features, and fully mechanise the numeric semantics of WebAssembly's integer operations.
CQS: A Formally-Verified Framework for Fair and Abortable Synchronization
Authors: Koval Nikita , Khalanskiy Dmitry , Alistarh Dan
Published: June 2023

Writing concurrent code that is both correct and efficient is notoriously difficult. Thus, programmers often prefer to use synchronization abstractions, which render code simpler and easier to reason about. Despite a wealth of work on this topic, there is still a gap between the rich semantics provided by synchronization abstractions in modern programming languages—specifically,
fair
FIFO ordering of synchronization requests and support for
abortable
operations—and frameworks for implementing it correctly and efficiently. Supporting such semantics is critical given the rising popularity of constructs for asynchronous programming, such as coroutines, which abort frequently and are cheaper to suspend and resume compared to native threads.

This paper introduces a new framework called CancellableQueueSynchronizer (CQS), which enables simple yet efficient implementations of a wide range of fair and abortable synchronization primitives: mutexes, semaphores, barriers, count-down latches, and blocking pools. Our main contribution is algorithmic, as implementing both fairness and abortability efficiently at this level of generality is non-trivial. Importantly, all our algorithms, including the CQS framework and the primitives built on top of it, come with
formal proofs
in the Iris framework for Coq for many of their properties. These proofs are modular, so it is easy to show correctness for new primitives implemented on top of CQS. From a practical perspective, implementation of CQS for native threads on the JVM improves throughput by up to two orders of magnitude over Java’s AbstractQueuedSynchronizer, the only practical abstraction offering similar semantics. Further, we successfully integrated CQS as a core component of the popular Kotlin Coroutines library, validating the framework’s practical impact and expressiveness in a real-world environment. In sum, CancellableQueueSynchronizer is the first framework to combine expressiveness with formal guarantees and solid practical performance. Our approach should be extensible to other languages and families of synchronization primitives.
Memento: A Framework for Detectable Recoverability in Persistent Memory
Authors: Cho Kyeongmin , Jeon Seungmin , Raad Azalea , Kang Jeehoon
Published: June 2023

Persistent memory (PM) is an emerging class of storage technology that combines the performance of DRAM with the durability of SSD, offering the best of both worlds. This had led to a surge of research on persistent objects in PM. Among such persistent objects, concurrent data structures (DSs) are particularly interesting thanks to their performance and scalability. One of the most widely used correctness criteria for persistent concurrent DSs is
detectable recoverability
, ensuring both thread safety (for correctness in non-crashing concurrent executions) and crash consistency (for correctness in crashing executions). However, the existing approaches to designing detectably recoverable concurrent DSs are either limited to simple algorithms or suffer from high runtime overheads.

We present Memento: a
general
and
high-performance
programming framework for detectably recoverable concurrent DSs in PM. To ensure general applicability to various DSs, Memento supports primitive operations such as checkpoint and compare-and-swap and their composition with control constructs. To ensure high performance, Memento employs a timestamp-based recovery strategy that requires fewer writes and flushes to PM than the existing approaches. We formally prove that Memento ensures detectable recoverability in the presence of crashes. To showcase Memento, we implement a lock-free stack, list, queue, and hash table, and a combining queue that detectably recovers from random crashes in stress tests and performs comparably to existing hand-tuned persistent DSs with and without detectable recoverability.
Performal: Formal Verification of Latency Properties for Distributed Systems
Authors: Zhang Tony Nuda , Sharma Upamanyu , Kapritsos Manos
Published: June 2023

Understanding and debugging the performance of distributed systems is a notoriously hard task, but a critical one. Traditional techniques like logging, tracing, and benchmarking represent a best-effort way to find performance bugs, but they either require a full deployment to be effective or can only find bugs after they manifest. Even with such techniques in place, real deployments often exhibit performance bugs that cause unwanted behavior.

In this paper, we present Performal, a novel methodology that leverages the recent advances in formal verification to provide rigorous latency guarantees for real, complex distributed systems. The task is not an easy one: it requires carefully decoupling the formal proofs from the execution environment, formally defining latency properties, and proving them on real, distributed implementations. We used Performal to prove rigorous upper bounds for the latency of three applications: a distributed lock, ZooKeeper and a MultiPaxos-based State Machine Replication system. Our experimental evaluation shows that these bounds are a good proxy for the behavior of the deployed system and can be used to identify performance bugs in real-world systems.
Loop Rerolling for Hardware Decompilation
Authors: Sisco Zachary D. , Balkind Jonathan , Sherwood Timothy , Hardekopf Ben
Published: June 2023

We introduce the new problem of
hardware decompilation
. Analogous to software decompilation, hardware decompilation is about analyzing a low-level artifact—in this case a
netlist
, i.e., a graph of wires and logical gates representing a digital circuit—in order to recover higher-level programming abstractions, and using those abstractions to generate code written in a hardware description language (HDL). The overall problem of hardware decompilation requires a number of pieces. In this paper we focus on one specific piece of the puzzle: a technique we call
hardware loop rerolling
. Hardware loop rerolling leverages clone detection and program synthesis techniques to identify repeated logic in netlists (such as would be synthesized from loops in the original HDL code) and
reroll
them into syntactic loops in the recovered HDL code. We evaluate hardware loop rerolling for hardware decompilation over a set of hardware design benchmarks written in the PyRTL HDL and industry standard SystemVerilog. Our implementation identifies and rerolls loops in 52 out of 53 of the netlists in our benchmark suite, and we show three examples of how hardware decompilation can provide concrete benefits: transpilation between HDLs, faster simulation times over netlists (with mean speedup of 6x), and artifact compaction (39% smaller on average).