bluuebunny/crossref_metadata_2025 huggingface dataset:
Resection versus resection with ablation: Analysis from the colorectal liver operative metastasis international collaborative
Authors: Mainali Bigyan B. , Valenzuela Cristian D. , Moaven Omeed , Stauffer John A. , Del Piccolo Nico R. , Cheung Tanto , Corvera Carlos U. , Wisneski Andrew D. , Cha Charles H. , Zarandi Nima P. , Dourado Justin , Russell Gregory , Shen Perry
Published: August 2024

Background

Thermal ablation has recently become a key therapy for the treatment of colorectal liver metastasis (CLM). However, the role of ablation in combination with resection has not yet been firmly established. We hypothesize that in patients with CLM, those who undergo liver resection with ablation (RA) have similar outcomes compared with those who undergo liver resection only.

Methods

We reviewed a multicenter international database of 906 surgical procedures for CLM from 5 high volume hepatobiliary surgical units. Patients undergoing RA (n = 63) were matched based on the number of lesions and tumor size using a 1:1 balanced propensity score analysis with those having resection only (n = 63). Our primary outcomes were overall survival (OS) and disease‐free survival (DFS).

Results

The mean age of our cohort was 58 ± 11 years, with 43% females. With a median follow‐up of 70.8 months, patients in the resection and RA group had a median OS of 45.1 and 54.8 months (p = 0.71), respectively. The median DFS was 22.7 and 14.2 months (p = 0.045), respectively. Using a multivariate Cox proportional hazards regression model, the treatment approach was not associated with OS (p = 0.94) or DFS (p = 0.059). A higher number of lesions is independently associated with worse DFS (hazard ratio: 1.12, p < 0.01). When there was disease recurrence, the region of recurrence was similar between the RA versus resection only groups (p = 0.27), but there was a shorter time to recurrence in the RA group (p = 0.002).

Conclusion

For CLM, the treatment approach was not significantly associated with OS or DFS, while tumor biology likely played an important role. Prospective research on the quality and effectiveness of thermal ablation combined with hepatic resection is warranted.
Prognostic impact of aberrant right hepatic artery involvement in patients with pancreatic cancer: A multicenter retrospective cohort study
Authors: Ueda Hiroki , Takahashi Hidenori , Akita Hirofumi , Tomimaru Yoshito , Kobayashi Shogo , Kubo Masahiko , Mukai Yousuke , Toshiyama Reishi , Sasaki Kazuki , Hasegawa Shinichiro , Iwagami Yoshifumi , Sakai Kenji , Yamada Daisaku , Noda Takehiro , Asaoka Tadafumi , Wada Hiroshi , Gotoh Kunihito , Doki Yuichiro , Eguchi Hidetoshi
Published: August 2024

Background and Objectives

This study aimed to evaluate the prognostic value of aberrant right hepatic artery (A‐RHA) involvement in patients with pancreatic cancer (PC).

Methods

This study enrolled 474 patients who underwent upfront pancreatectomy or neoadjuvant treatment for resectable (R) or borderline resectable (BR) PC from four institutions. The patients were divided into three groups: A‐RHA involvement group (n = 12), patients who had sole A‐RHA involvement without major arterial involvement; BR‐A group (n = 104), patients who had major arterial involvement; R/BR‐PV group (n = 358), others.

Results

All patients in the A‐RHA involvement group underwent margin‐negative resection. The median overall survival of the entire cohort in the A‐RHA involvement, R/BR‐PV, and BR‐A groups was 41.2, 33.5, and 25.2 months, respectively. Although survival in the R/BR‐PV group was significantly more favorable than that in the BR‐A group (p = 0.0003), no significant difference was observed between the A‐RHA involvement group and the R/BR‐PV (p = 0.7332) and BR‐A (p = 0.1485) groups.

Conclusions

The prognosis of patients with PC and sole A‐RHA involvement was comparable to that of patients with R/BR‐PV.
Must we lose our biological connection to nature to endure changing times?
Authors: Berger Joel , Bleich Vernon C. , Terry Bowyer R.
Published: August 2024

Earth has >8 billion people. Scholarly publications number nearly 7 million annually with >1 million in the life and biomedical sciences, and ≥52 professional journals specializing in conservation, ecology, or related disciplines. The challenges of applying ecological data to conservation and wildlife management can easily become overwhelming. Herein we offer reflective perspectives about the changing face of applied knowledge and engagement from our personal employment histories as ecologists working in agency, university, and non‐governmental organization (NGO) biologist positions. We suggest natural history will always be nature's glue, but knowledge steeped mostly in muddy boots and field biology are no longer the soup du jour of our profession. In many ways, new technologies have changed data collection and the scientific questions asked. Arguably, such change is not welcomed by all, but a change in overlap across decades is needed to sustain and improve upon how the planet's biological diversity can coexist with increasingly difficult human conditions. Given that 80% of the people in the United States live in urban areas, with similar numbers internationally, a future possibility may be an even greater divide between wild nature, ecological services, and enjoyment in the field. This is disturbing. Despite fundamental scientific insights that help understand critical components of the natural world, once society loses touch with nature, what will remain?
Technical note: Phantom‐based evaluation of CBCT dose calculation accuracy for use in adaptive radiotherapy
Authors: Wessels Claas , Strzelecki Adam , Plamondon Mathieu , Lehmann Mathias , Peterlik Igor , Paysan Pascal , Nagy Balazs , Heinz Alexander , Seghers Dieter , Thompson Stephen , Scheib Stefan G.
Published: August 2024

Background

High‐quality 3D‐anatomy of the day is needed for treatment plan adaptation in radiotherapy. For online x‐ray‐based CBCT workflows, one approach is to create a synthetic CT or to utilize a fan‐beam CT with corresponding registrations. The former potentially introduces uncertainties in the dose calculation if deformable image registration is used. The latter can introduce burden and complexity to the process, the facility, and the patient.

Purpose

Using the CBCT of the day, acquired on the treatment device, for direct dose calculation and plan adaptation can overcome these limitations. This study aims to assess the accuracy of the calculated dose on the CBCT scans acquired on a Halcyon linear accelerator equipped with HyperSight.

Methods

HyperSight's new CBCT reconstruction algorithm includes improvements in scatter correction, HU calibration of the imager, and beam shape adaptation. Furthermore, HyperSight introduced a new x‐ray detector. To show the effect of the implemented improvements, gamma comparisons of 2%/2 mm, 2%/1 mm, and 1%/1 mm were made between the dose distribution in phantoms calculated on the CBCT reconstructions and the simulation CT scans, considering this the standard of care. The resulting gamma passing rates were compared to those obtained with the Halcyon 3.0 reconstruction and hardware without HyperSight's technologies. Various anatomical phantoms for dosimetric evaluations on brain, head and neck, lung, breast, and prostate cases have been used in this study.

Results

The overall results demonstrated that HyperSight outperformed the Halcyon 3.0 version. Based on the gamma analysis, the calculated dose using HyperSight was closer to the CT scan‐based doses than the calculated dose using iCBCT Halcyon 3.0 for most cases. Over all plans and gamma criteria, Halcyon 3.0 achieved an average passing rate of 92.9%, whereas HyperSight achieved 98.1%.

Conclusion

Using HyperSight CBCT images for direct dose calculation, for example, in (online) plan adaptation, seems feasible for the investigated cases.
Geometry accuracy control in abrasive water jet taper hole machining of ultra‐thick carbon fiber‐reinforced polymer (CFRP) laminates
Authors: Liang Wei , Cheng Liang , Dong Huiyue , Zhu Minghua , Guo Yingjie , Ke Yinglin
Published: August 2024

The primary factors affecting the geometric accuracy of abrasive water jet (AWJ) machining of ultra‐thick carbon fiber‐reinforced polymer (CFRP) laminates are the cutting front drag and kerf width deviation caused by energy dissipation. Firstly, this study comprehensively analyzes the influence of the coupling relationship between cutting front drag and kerf width deviation on the geometric accuracy of hole machining. Secondly, a gradient distribution theory for jet traverse speed with cutting depth is proposed for taper hole machining characteristics. Finally, a general geometric error model applicable to both straight and taper hole machining of ultra‐thick CFRP laminates using AWJ is established, along with a geometric error compensation method. A series of experiments validate the accuracy of the proposed geometric error model and compensation method. The novelty of this research lies in unifying the geometric error models for straight and taper hole machining of ultra‐thick CFRP laminates by considering the gradient distribution of jet traverse speed. The proposed error compensation method reduces the high degree of freedom required for machine tools. This study provides a general geometric error model and compensation strategy for AWJ hole machining of ultra‐thick CFRP laminates, which has significant engineering value for achieving 3D controllable AWJ machining of complex ultra‐thick CFRP components.

Highlights

The high geometric precision taper holes machining technique is a necessary prerequisite for achieving precise machining of complex trajectories in ultra‐thick CFRP with abrasive water jet.

The influence of the coupling relationship between cutting front drag and kerf taper on the geometric accuracy of hole processing is comprehensively analyzed.

A model considering the gradient distribution of traverse speed during taper holes machining was established, and a geometric error model considering this gradient distribution of traverse speed was developed.

A taper holes machining geometric error compensation method with high engineering applicability was proposed.

Geometric error prediction experiments and error compensation experiments were conducted, and the results proved the accuracy of the geometric error model and error compensation method.
Interface modification strategy to construct SiC nanowires@pyrolytic carbon reinforcement for carbon fiber composites
Authors: Wan Xinyi , Zhang Leilei , Shen Xuetao , Wang Tiantian , Sheng Hongchao , Li Hejun
Published: August 2024

Designing and optimizing the interface of carbon fiber composites is the key to improve mechanical and biotribological properties. Carbon fiber‐reinforced hydroxyapatite‐epoxy matrix (CM) composites, which have excellent mechanical and biotribological properties, are often used to avoid artificial bone damage and improve the longevity of artificial bone. In this work, a SiC nanowires@pyrolytic carbon (SiCnws@PyC) is designed and incorporated into the CM to improve the mechanical and biotribological properties. SiCnws@PyC can promote bonding of the fiber/matrix interface and cohesion of the epoxy matrix. The mechanical and biotribological properties of CM are greatly improved because of the interface modification and reinforcement of SiCnws@PyC. The tensile strength and elastic modulus of SiCnws@PyC‐reinforced CM are 18.73% and 38.71% higher than those of CM, respectively. SiCnws@PyC‐reinforced CM has a 9.09% reduction in the friction coefficient and a 74.61% reduction in the wear rate. This study provides a promising methodology for the preparation of SiCnws@PyC‐reinforced CM with better stability and longevity for bone grafting applications.

Highlights

The mechanism of SiC nanowires@pyrolytic carbon (SiCnws@PyC) is explained.

The SiCnws@PyC structure is designed into composites.

PyC core‐shell transforms the structure of hydroxyapatite.

The SiCnws@PyC enhances mechanical and biotribological properties of composites.
Nirmatrelvir/Ritonavir (Paxlovid) Use Among Individuals at Risk of Severe COVID‐19: An Analysis of the National COVID Cohort Collaborative (N3C)
Authors: Xiao Xuya , Alexander G. Caleb , Mehta Hemalkumar B.
Published: August 2024

Purpose

Paxlovid is effective in reducing COVID‐19 hospitalization and mortality. This study characterized Paxlovid use and evaluated racial/ethnic disparities over time among community‐dwelling adults at high risk of progression to severe COVID‐19 disease.

Methods

This retrospective cohort study used the National COVID Cohort Collaborative (N3C) data and included individuals aged 18 years or older diagnosed with COVID‐19 between January 2022 and December 2023. The study cohort included nonhospitalized individuals who were at high risk of COVID‐19 progression, and selected the first COVID‐19 episode in each quarter, including reinfection episodes. Paxlovid use was defined as receiving Paxlovid within ±5 days of a COVID‐19 diagnosis. We used descriptive statistics to characterize Paxlovid use overall and by calendar quarter and race/ethnicity. We used a generalized estimating equations (GEE) models to quantify the association of race/ethnicity with Paxlovid use controlling for age, gender, and clinical characteristics.

Results

Among 1 264 215 individuals at high risk of disease progression (1 404 607 episodes), Paxlovid use increased from 1.2% in January–March 2022 to 35.1% in October–December 2023. Paxlovid use was more common among non‐Hispanic White individuals (23.9%) than non‐Hispanic Black (16.5%) and Latinx/e (16.7%) patients. After adjusting age, gender, and clinical characteristics, Paxlovid use was less likely among non‐Hispanic Black (odds ratio [OR] 0.69, 95% confidence interval [CI] 0.68–0.70) and Latinx/e (OR 0.72, CI 0.71–0.73) patients than non‐Hispanic White patients.

Conclusions

Among a large, diverse cohort of community‐dwelling individuals with COVID‐19, nearly two out of three eligible individuals did not receive Paxlovid, and minoritized racial/ethnic groups were less likely to use Paxlovid than their non‐Hispanic White individuals.
Estimation of Treatment Policy Estimands for Continuous Outcomes Using Off‐Treatment Sequential Multiple Imputation
Authors: Drury Thomas , Abellan Juan J. , Best Nicky , White Ian R.
Published: August 2024

The estimands framework outlined in ICH E9 (R1) describes the components needed to precisely define the effects to be estimated in clinical trials, which includes how post‐baseline ‘intercurrent’ events (IEs) are to be handled. In late‐stage clinical trials, it is common to handle IEs like ‘treatment discontinuation’ using the treatment policy strategy and target the treatment effect on outcomes regardless of treatment discontinuation. For continuous repeated measures, this type of effect is often estimated using all observed data before and after discontinuation using either a mixed model for repeated measures (MMRM) or multiple imputation (MI) to handle any missing data. In basic form, both these estimation methods ignore treatment discontinuation in the analysis and therefore may be biased if there are differences in patient outcomes after treatment discontinuation compared with patients still assigned to treatment, and missing data being more common for patients who have discontinued treatment. We therefore propose and evaluate a set of MI models that can accommodate differences between outcomes before and after treatment discontinuation. The models are evaluated in the context of planning a Phase 3 trial for a respiratory disease. We show that analyses ignoring treatment discontinuation can introduce substantial bias and can sometimes underestimate variability. We also show that some of the MI models proposed can successfully correct the bias, but inevitably lead to increases in variance. We conclude that some of the proposed MI models are preferable to the traditional analysis ignoring treatment discontinuation, but the precise choice of MI model will likely depend on the trial design, disease of interest and amount of observed and missing data following treatment discontinuation.
Gel Polymer Electrolyte Enables Low‐Temperature and High‐Rate Lithium‐Ion Batteries via Bionic Interface Design
Authors: Liu Xiaofei , Wang Dong , Zhang Zibo , Li Gaunwu , Wang Jian , Yang Guangmin , Lin Hongzhen , Lin Jianyan , Ou Xing , Zheng Weitao
Published: August 2024

Traditional ethylene carbonate (EC)‐based electrolytes constrain the applications of silicon carbon (Si‐C) anodes under fast‐charging and low‐temperature conditions due to sluggish Li+ migration kinetics and unstable solid electrolyte interphase (SEI). Herein, inspired by the efficient water purification and soil stabilization of aquatic plants, a stable SEI with a 3D desolvation interface is designed with gel polymer electrolyte (GPE), accelerating Li+ desolvation and migration at the interface and within stable SEI. As demonstrated by theoretical simulations and experiment results, the resulting poly(1,3‐dioxolane) (PDOL), prepared by in situ ring‐opening polymerization of 1,3‐dioxolane (DOL), creates a 3D desolvation area, improving the Li+ desolvation at the interface and yielding an amorphous GPE with a high Li+ ionic conductivity (5.73 mS cm−1). Furthermore, more anions participate in the solvated structure, forming an anion‐derived stable SEI and improving Li+ transport through SEI. Consequently, the Si‐C anode achieves excellent rate performance with GPE at room temperature (RT) and low temperature (−40 °C). The pouch full cell coupled with LiFePO4 cathode obtains 97.42 mAh g−1 after 500 cycles at 5 C/5 C. This innovatively designed 3D desolvation interface and SEI represent significant breakthroughs for developing fast‐charging and low‐temperature batteries.
Injectable Regenerated Silk Fibroin Micro/Nanosphere with Enhanced Permeability and Stability for Osteoarthritis Therapy
Authors: Wang Zixiang , Yin Xueyang , Zhuang Chenyang , Wu Kang , Wang Huiren , Shao Zhengzhong , Tian Bo , Lin Hong
Published: August 2024

In the therapy of early‐stage osteoarthritis, to accomplish full infiltration of subchondral bone and cartilage, and to target osteoclast and chondrocyte simultaneously remain challenges in biomaterials design. Herein, a novel hierarchical drug delivery system is introduced, with micrometer‐scale outer layer spheres composed of regenerated silk fibroin, characterized by connected porous structure through the n‐butanol and regenerated silk fibroin combined emulsion route and freezing method. The design effectively resists clearance from the joint cavity, ensuring stable delivery and prolonged residence time within the joint space. Additionally, the system incorporates phenylboronic acid‐enriched silk fibroin nanoparticles, stabilized through chemical cross‐linking, which encapsulate isoliquiritin derived from Glycyrrhiza uralensis. These nanoparticles facilitate complete penetration of the cartilage extracellular matrix, exhibit pH‐responsive behavior, neutralize reactive oxygen species, and enable controlled drug release, thereby enhancing therapeutic efficacy. The in vitro and in vivo experiments both demonstrate that the composite micro/nanospheres not only inhibit osteoclastogenesis with bone loss in subchondral bone and osteophyte formation, but also mitigate chondrocytes apoptosis, reduce oxidative stress associated with cartilage degeneration, and ameliorate neuropathic hyperalgesia, with the underlying mechanisms being elucidated. The study indicates that such an injectable strategy combining organic biomaterials with Chinese medicine holds substantial promise for the treatment of early osteoarthritis.
Electrochemically Active MoO3/TiN Sulfur Host Inducing Dynamically Reinforced Built‐in Electric Field for Advanced Lithium–Sulfur Batteries
Authors: Lee Jeongyoub , Kim Sumin , Park Jung Been , Park Daerl , Lee Sangjun , Choi Changhoon , Lee Hyungsoo , Jang Gyumin , Park Young Sun , Yun Juwon , Moon Subin , Lee Soobin , Jeong Chang‐Seop , Kim Jun Hwan , Choi Heon‐Jin , Kim Dong‐Wan , Moon Jooho
Published: August 2024

Although various electrocatalysts have been developed to ameliorate the shuttle effect and sluggish Li–S conversion kinetics, their electrochemical inertness limits the sufficient performance improvement of lithium–sulfur batteries (LSBs). In this work, an electrochemically active MoO3/TiN‐based heterostructure (MOTN) is designed as an efficient sulfur host that can improve the overall electrochemical properties of LSBs via prominent lithiation behaviors. By accommodating Li ions into MoO3 nanoplates, the MOTN host can contribute its own capacity. Furthermore, the Li intercalation process dynamically affects the electronic interaction between MoO3 and TiN and thus significantly reinforces the built‐in electric field, which further improves the comprehensive electrocatalytic abilities of the MOTN host. Because of these merits, the MOTN host‐based sulfur cathode delivers an exceptional specific capacity of 2520 mA h g−1 at 0.1 C. Furthermore, the cathode exhibits superior rate capability (564 mA h g−1 at 5 C), excellent cycling stability (capacity fade rate of 0.034% per cycle for 1200 cycles at 2 C), and satisfactory areal capacity (6.6 mA h cm−2) under a high sulfur loading of 8.3 mg cm−2. This study provides a novel strategy to develop electrochemically active heterostructured electrocatalysts and rationally manipulate the built‐in electric field for achieving high‐performance LSBs.
Dynamic response and blast resistance of I‐shaped steel‐concrete composite beam under explosive loading
Authors: Li Yuan , Lin Qutong , Liu Jianyu
Published: August 2024

To investigate the dynamic mechanical response and damage mechanisms of I‐shaped steel‐concrete composite beams under explosive loads, experimental research and numerical simulations were conducted on steel‐concrete composite structures. The accuracy of the numerical analysis model was validated by comparing the damage characteristics of the structures obtained from explosive tests on the steel‐concrete composite components. Based on this, numerical simulations were performed on steel‐concrete composite beams using the explicit dynamic analysis software ANSYS/LS‐DYNA, and a study on their damage mechanisms was conducted. This study resulted in the acquisition of dynamic mechanical response patterns, including time‐dependent stress, strain, displacement, acceleration, and so on. Different structural damage characteristics under various explosive conditions were summarized, and key parameters affecting the blast resistance of the structure were analyzed. The research findings indicated that, in contrast to the failure characteristics of I‐shaped reinforced concrete (RC) beams, the failure characteristics of I‐shaped steel‐concrete composite beams mainly include punching and shearing failure of the steel‐RC slab and local buckling of the steel beam. Under the same explosive conditions, steel‐concrete composite structures exhibit superior blast resistance, with certain changes in structural parameters significantly improving blast resistance. The research results can provide theoretical support and a scientific basis for the proactive design of blast protection in steel‐concrete beams.
Becoming and being a critical language teacher educator: A duoethnography
Authors: Tezgiden‐Cakcak Yasemin , Ataş Ufuk
Published: August 2024

Language teacher educator (LTE) identity development is an emerging field exploring how LTEs learn to teach and negotiate their identities and how their identity construction processes help teacher candidates learn. The complexity of the issue has prompted researchers to explore their professional journeys and experiences in various contexts from differing perspectives. Still, the field is constantly evolving as LTEs strive to understand the multifaceted nature of the profession and its implications for teacher education. Within this perspective, through a duoethnographic study, in this research the authors aim to explore how they construct, negotiate, and enact their critical LTE identities and agency as two Turkish‐speaking, mid‐career English language teacher educators situated currently in two different higher education institutions in Türkiye. The researchers collected lengthy personal narratives recounting their experiences and thematically analyzed them through iterative coding. Three major themes concerning their meso and micro contexts emerged: their trajectories in becoming LTEs, issues of belonging and marginalization, negotiating their LTE identities, and exercising agency. Their narratives indicate how they followed different trajectories to become teacher educators, were positioned as others in their institutional settings, legitimized their LTE identities in time, and became empowered to practice their aspired identities. Despite being marginalized in different contexts, their narratives show they have consistently created counter‐hegemonic discursive and experiential spaces in their classrooms and institutional contexts as micro‐level policy‐makers enacting their critical LTE identities.
A Typology on Business Model Integration
Authors: Öberg Christina
Published: August 2024

Currently, we are witnessing firms engaging in acquisitions to explore new business models. However, despite operating within similar industry sectors, integrating these business models can be challenging. Beyond the mere integration of operational aspects, this paper argues that business model integration should encompass two crucial dimensions: the integration of market architectural strategies and the assimilation of mindsets that drive market operations. The paper constructs a typology for business model integration, grounded in the integration of market architectural strategies, and mindsets and illustrates the types through international acquisition examples. The paper contributes to existing research by exploring integration within the context of business model acquisitions. The division into market architectural strategies and mindset advances past understanding of business models. The conceptualization of “value‐creation culture” extends the boundaries of past acquisition research and underscores the significance of mindsets associated with new business models.
An investigation of the heat and mass transfer effects in vertical channels with immersible fluid flow through a porous matrix
Authors: Kandagal Mangala , Kempepatil Ramesh
Published: August 2024

In this article, we investigated the heat and mass transfer of immiscible fluid flow in symmetric two‐vertical regions with a porous matrix in region‐II. The properties of heat generation and absorption are discussed. The channel, consisting of two vertical regions, is filled with a porous matrix with viscous fluids. In both cases, we considered the fluids that undergo Newtonian heat generation and absorption. It was assumed that the porous matrix's channel wall was thermally stable and electrically non‐conducting. The analytical method is used to solve governing equations. Variations in Brinkman Number (Br), Biot Number (Bi), Grashof (Gr) number, viscosity ratio (m), heat generation, and thermal conductivity are illustrated graphically. And we examined the increase in Grashof number, which has effects on fluid flows in both regions. Similarly, the change of heat and momentum transmission in porous media is greatly affected by the viscosity, channel width, source, and sink. Also, when the Grashof number increases, buoyancy increases, leading to an increase in the fluid flow for heat generation and absorption.
Numerical Analysis of Inhomogeneous Parameters of Paperboard Using Tensile Tests
Authors: Leng Yuchen , Sanjon Cedric Wilfried , Groche Peter , Hauptmann Marek , Majschak Jens-Peter
Published: August 2024

For pure metals, typically a homogeneous distribution of material properties is assumed. This assumption reduces the complexity of the models significantly. For inhomogeneous materials like paperboard, however, this assumption is questionable. Experimental findings indicate that the structural inhomogeneity can lead to variations in mechanical properties, which in turn reduce the robustness of processes and require actions to control the product quality. In this work, we introduce an approach to modeling the local material structure in numerical simulations and investigate the material response to an uniaxial tensile test. The effect of various inhomogeneities, e.g., distribution of mass, density, and fiber orientation, on material properties was investigated, and it was found that fiber orientation has the greatest effect in most cases, while the effect of density is usually the least.
Determining Critical Wall Angle in Micro-incremental Sheet Forming of SS316L Foils for Formability Assessment
Authors: Pal Mainak , Pandya Vandit , Nirala Chandrakant K. , Agrawal Anupam
Published: August 2024

Micro-incremental sheet forming (µISF) has advantages over existing micro-forming processes (due to its die-less nature of material deformation) and vast applications in sophisticated industries. In µISF, a flexible ultra-thin sheet (foil) is plastically deformed into a complex 3D geometrical shaped component. It is precisely governed by the user-defined toolpath of the forming tool on the surface of the foil. This study investigated the deformation behavior of 100-μm-thick SS316L foils; the foils were deformed into small conical shapes with a tool-tip with a radius of 500 μm. The µISF process set-up consisted of a rigid fixture to avoid any unwanted distortions during the forming. To test the formability of the foils at different working parameters, experimental and numerical examinations were conducted by varying the wall angle (α = 45°, 60°, 75°) of the forming with three different step depths (∆z = 10, 20, and 30 μm). A finite element analysis of the process was carried out using ABAQUS® software; the results revealed that the forming angle in µISF had a direct relationship with the formability of the material. Higher values of the step depth assisted in increasing the formability of the SS316L foils. To examine the critical wall angle (αcr) and critical foil thickness (tcr) at the fracture location, a higher range of α (70°–74°) was selected in order to establish a correlation with the depth of the forming.
Optimization of the Heat Transfer Simulation Time During 3D Printing of PLA Material
Authors: Benié Kandy , Cherouat Abel , Barrière Thierry , Placet Vincent
Published: August 2024

This work focused on optimizing the simulation time for heat transfer during the Fused Deposition Modeling process, which is necessary for a recent tensile property optimization study mentioned in the literature. The approach for optimizing the simulation time involved conducting a comparative analysis of various mesh sizes and simulation step times, assessing their influence on the resulting temperature profiles. The heat transfer simulation of the printed material was done with COMSOL Multiphysics FEA and the normal and extremely fine meshes as well as the simulation step times of $$\Delta t$$

Δ
t

= 0.01 and 0.05 s were considered. The results showed that all the combinations resulting from these simulation parameters were equivalent in terms of both temperature profile results and the results of the tensile property optimization study, but that the simulation time was minimized by using the normal mesh with Δt = 0.05 s with a simulation time ten times shorter than in the case of the extremely fine mesh with $$\Delta t$$

Δ
t

= 0.01 s.
Deformation of Elastically Inhomogeneous Solid Modelled with Diffuse Interface Approach
Authors: Pohjonen Aarne
Published: August 2024

Diffuse interfaces are useful tools for simulating evolution of material phases, and they are fundamentally important part of the phase field method. Since, in solid state, different phases can have different elastic constants, it is important to be able to incorporate them into the numerical simulations. In current study, the theory of deformation of elastically inhomogeneous solid with diffuse interface approach and application of relatively simple numerical method for solving the problem are described. Deformation of a solid containing an elastical inhomogeneity is simulated for two cases for compression in two-dimensional plane strain condition: a harder inclusion and a softer inclusion.
Effect of Work Roll Surface Warming on Hot Strip Temperature Development in Industrial Scale Virtual Rolling Model
Authors: Ilmola Joonas , Paananen Joni , Larkiola Jari
Published: August 2024

Digitalization is taking place in the steel industry and novel virtual rolling models will be implemented into industrial systems. Virtual rolling models are mainly assembled of individual models for modeling the rolling process considering mechanical, thermal and metallurgical phenomena. Advanced virtual rolling models even predict mechanical properties based on modeled metallurgical state. These models for certain phenomena do not usually consider the constantly changing process parameters which affect the temperature of rolled strip in the industrial process. In the hot rolling industry, temperature development is of particular importance. To calculate temperature development accurately throughout the rolling process, multiple thermal boundary conditions must be considered. In this investigation, we used the FE-model to study how parameters of rolling pass, work roll coolers and full length transfer strip affect warming of a work roll surface. These results were utilized in prediction of work roll surface temperature in contact between the work roll and the strip over full length strip rolling in virtual rolling model to model development of strip temperature in full scale industrial hot strip rolling process.
Capital Accumulation
Authors: Prados de la Escosura Leandro
Published: August 2024

This chapter provides and analyses new estimates of net capital stock and services for Spain over the last 170 years. The net capital (wealth) stock-GDP ratio rose over time and doubled in the last half a century. Capital services grew fast over the long run, accelerating in the 1920s and from the mid-1950s to 2007. Until 1975, their acceleration was assisted by an increase in the ‘quality’ of capital. Capital deepening proceeded steadily, accelerating from 1955 to 1985, and slowed down thereafter, for expanding sectors attracted less investment-specific technological progress. Although capital consumption rose over time, the rate of depreciation fell from 1970 to 2007, as the relative prices of new capital goods’ declined due to embodied technological change.
Spain’s Financial Position in the First Globalization
Authors: Prados de la Escosura Leandro
Published: August 2024

Spain’s financial position during the late nineteenth and early twentieth century has usually been depicted as one of persistent deficit on current account, resulting from the country’s integration into international commodity and factor markets, which would have slowed down economic growth. In this chapter, this proposition is tested on the basis of a reconstruction of the Spanish balance of payments on current account. At odds with this interpretation, during the first globalization, opening up until 1890 allowed a net capital inflow that made it possible to meet the demand for investment boosting economic performance. Conversely, current account reversals in a context of macroeconomic domestic imperfections help explain the economic slowdown at the turn of the century.
Two-loop mixed QCD-EW corrections to charged current Drell-Yan
Authors: Armadillo Tommaso , Bonciani Roberto , Devoto Simone , Rana Narayan , Vicini Alessandro
Published: August 2024

Abstract

We present the two-loop mixed strong-electroweak virtual corrections to the charged current Drell-Yan process. The final-state collinear singularities are regularised by the lepton mass. The evaluation of all the relevant Feynman integrals, including those with up to two different internal massive lines, has been worked out relying on semi-analytical techniques, using complex-valued masses. We can provide, at any arbitrary phase-space point, the solution as a power series in the W-boson mass, around a reference value. Starting from these expansions, we can prepare a numerical grid for any value of the W-boson mass within their radius of convergence in a negligible amount of time.
Entanglement of defect subregions in double holography
Authors: Liu Yuxuan , Chen Qian , Ling Yi , Peng Cheng , Tian Yu , Xian Zhuo-Yu
Published: August 2024

Abstract

In the framework of double holography, we investigate the entanglement behavior of a subregion of the defect on the boundary of a CFT3. The entanglement entropy of this defect subregion is determined by the quantum extremal surface (QES) anchored at the two endpoints of the subregion from the brane perspective. We further analyze the entanglement entropy of the quantum matter within this QES, which can be extracted from the total entanglement entropy. We find there are two phases of the QES. To numerically distinguish these phases, we design a strategy for approaching the QES by progressively reducing the width of a semi-ellipse-like region within the CFT3, which is bounded by the defect. During this process, we discover an entanglement phase transition driven by the degree of freedom on the brane. In the shrinking phase, the entanglement wedge of the defect subregion sharply decreases to zero as the removal of the CFT3. In contrast, in the stable phase, the wedge almost remains constant. In this phase, the formulas of entanglement measures can be derived based on defect and CFT3 central charges in the semi-classical limit. For entanglement entropy, the classical geometry only contributes a subleading term with logarithmic divergence, but the matter entanglement exhibits a dominant linear divergence, even in the semi-classical limit. For the reflected entropy within the defect subregion, classical geometry contributes a leading term with logarithmic divergence, while the quantum matter within the entanglement wedge only contributes a finite term.
Semiclassics for the QCD vacuum structure through T2-compactification with the baryon-’t Hooft flux
Authors: Hayashi Yui , Tanizaki Yuya
Published: August 2024

Abstract

We study QCD vacuum structure with the topological θ angle using a recently proposed semiclassical approach on ℝ2 × T2 with the ’t Hooft and baryon magnetic fluxes. Under the assumption of adiabatic continuity in this setup, the confining vacuum can be described by the dilute gas of center vortices. With this semiclassical approach, we derive the 2d effective description at small T2 and successfully explain the reasonable theta dependence of the QCD vacuum: in the one-flavor QCD at θ = π, the CP symmetry is spontaneously broken for quark mass above a critical value and restored for a subcritical mass, while the CP symmetry is always spontaneously broken in the multi-flavor QCD at θ = π. From our semiclassical description, we discuss implications to the 4d chiral Lagrangian and propose how the η′ meson should be incorporated in consistent with known global structures: the periodicity of the η′ should be extended from the naive one 2π to 2πN. Additionally, we revisit the phase diagram of Nf = 1 + 1 and Nf = 1 + 1 + 1 QCD on the up and down quark mass plane, confirming and refining the existence of the CP-broken Dashen phase.
Higher-group global symmetry and the bosonic M5 brane
Authors: Armas Jay , Batzios Giorgos , Jain Akash
Published: August 2024

Abstract

Higher-group symmetries are combinations of higher-form symmetries which appear in various field theories. In this paper, we explain how higher-group symmetries arise in 10d and 11d supergravities when the latter are coupled to brane sources. Motivated by this observation, we study field theories at zero and finite temperature invariant under a class of continuous Abelian higher-group symmetries. We restrict the analysis to the low-energy regime where the dynamical field content exclusively consists of Goldstone fields arising from the spontaneous breaking of higher-group and spacetime symmetries. Invariant quantities are constructed and the phases of matter are classified according to the pattern of spontaneous symmetry breaking. With respect to supergravity, we highlight how such Goldstone effective theories provide a symmetry-based interpretation for the theories living on D/M-branes. As an explicit example we construct a 6-group invariant action for the bosonic M5 brane, consistent with the self-duality of the 3-form field strength on the brane. While the self-duality condition in the bosonic case needs to be imposed externally as a constraint at zero temperature, we find an equilibrium effective action for the bosonic M5 brane at finite temperature that inherently implements self-duality.
Discrete gauge anomalies and instantons
Authors: Jia Qiang , Yi Piljin
Published: August 2024

Abstract

We revisit anomalous phases related to large gauge transformations, such as the Witten anomaly. The latter, known to plague d = 4 Sp(k) theories, is well-understood in terms of π4(Sp(k)) = ℤ2, but it also has an oblique relation to the instantons, labeled by π3(G) = ℤ, via the fermion zero mode counting. We revisit this relation and point out how SU(N) theories escape an anomalous sign of the latter type, only thanks to the perturbative anomaly cancelation condition that restricts the chiral fermion spectrum. This leads to the question of what happens if the latter, more mundane anomaly is canceled by an inflow instead. After raising an open question about fractional D3 probe theories, we explore the simplest bottom-up model of such a kind, due to Witten and Yonekura, from which we find the relevant chiral theories to be free of such a disease despite the unrestricted chiral spectra. We close with a simple but often-overlooked observation about how fermionic zero modes enter physics differently between Euclidean and Lorentzian descriptions and point out a related issue in d = 3.
$$\text {CMC-1}$$ Surfaces in Hyperbolic and de Sitter Spaces with Cantor Ends
Authors: Castro-Infantes Ildefonso , Hidalgo Jorge
Published: August 2024

We prove that on every compact Riemann surface M, there is a Cantor set $$C \subset M$$

C
⊂
M

such that $$M{ \setminus }C$$

M
\
C

admits a proper conformal constant mean curvature one ($$\text {CMC-1}$$
CMC-1
) immersion into hyperbolic 3-space $$\mathbb {H}^3$$

H

3

. Moreover, we obtain that every bordered Riemann surface admits an almost proper $$\text {CMC-1}$$
CMC-1
face into de Sitter 3-space $$\mathbb {S}_1^3$$

S
1
3

, and we show that on every compact Riemann surface M, there is a Cantor set $$C \subset M$$

C
⊂
M

such that $$M {\setminus } C$$

M
\
C

admits an almost proper $$\text {CMC-1}$$
CMC-1
face into $$\mathbb {S}_1^3$$

S
1
3

. These results follow from different uniform approximation theorems for holomorphic null curves in $$\mathbb {C}^2 \times \mathbb {C}^*$$

C

2

×

C

∗

that we also establish in this paper.
Comparison of reinforcement fibers in 3D printing mortars using multi-criteria analysis
Authors: Alonso-Cañon Sara , Blanco-Fernandez Elena , Castro-Fresno Daniel , Yoris-Nobile Adrian I. , Castanon-Jano Laura
Published: August 2024

3D concrete printing (3DCP) has developed rapidly in recent years, with a relatively high amount of mortars emerging apt for 3D printing. Some of these mortars include fibers to improve their strength. Despite mechanical properties having been quite well studied, there still is missing information on cost, printability, and environmental impacts. The objective of this research is to select the best mortars with fibers considering four criteria: printability, mechanical strength, and economic and environmental impact applying a multi-criteria decision-making analysis (MCDMA). Seven types of fibers with different dosages were assessed in the reinforced mortars: zylon, aramid, carbon, glass, cellulose, textile, and polypropylene. AHP method and equal weights were used as ponderation techniques of the criteria while WASPAS and TOPSIS methods were used to calculate the rankings of the MCDMA. Printability was measured through rheological tests using a rotational rheometer, mechanical strength through flexural tests at 28 days based on EN 196–1, and cost just considering the materials and environmental impact through a life cycle assessment (LCA). The results showed that 13-mm-long glass fibers with a content of 0.1% were the best alternative, closely followed by the mortar with 6 mm cellulose fibers with a content of 0.05%. For the best option (G13;0.1), the increments in the printability index, flexural strength, cost, and LCA were − 14.37%, 16.70%, 5.88%, and 2.86%, respectively. It can also be concluded that high elastic modulus fibers (zylon and aramid), although able to increase significantly the flexural strength (up to 30% in the case of zylon), prevent them from being an optimal solution due to their high cost.
Effects of peanut ball use on perceived labor pain, fatigue, and mother’s perception of childbirth: a randomized controlled trial
Authors: Alan Dikmen Hacer , Gönenç İlknur Münevver , Ataş Ayşe Nur
Published: August 2024

Purpose

The aim of this study was to evaluate the effects of using peanut balls on labor pain, fatigue, and the mother’s perception of labor.

Methods

This is a randomized controlled intervention trial. Data were collected from the Intervention (peanut ball) and Control groups between July 2022 and June 2023, with 45 pregnant women in each group. Data were collected using a personal information form, the Visual Analog Scale-Pain (VAS-P), the Visual Analog Scale for Fatigue (VAS-F), and the Maternal Perception of Childbirth Scale (MPCS).

Results

The VAS-P scores of the intervention group were statistically significantly lower than those of the control group 15 min after peanut ball application (p = .000). Immediately after and 15 min after peanut ball application, the mean fatigue score of the Intervention group was statistically significantly lower than that of the Control group (p = .000). There was no statistically significant difference between the mean duration of labor minutes in the two groups (p = .177). The mean MPCS scores of the intervention group and control groups were 62.73 + 7.30 and 47.17 + 9.12, respectively, and the difference was statistically significant (p = .000).

Conclusions

The findings of this study indicate that the use of peanut balls during labor can effectively reduce labor pain and fatigue in pregnant women, without affecting the duration of labor. Additionally, the use of peanut balls has been shown to positively influence the perception of labor among pregnant women. Therefore, it is recommended that midwives educate pregnant women about the use of peanut balls during labor and provide support in their use.
Neuroplasticity in Parkinson’s disease
Authors: Popescu Bogdan Ovidiu , Batzu Lucia , Ruiz Pedro J. Garcia , Tulbă Delia , Moro Elena , Santens Patrick
Published: August 2024

Parkinson’s disease (PD) is the second most frequent neurodegenerative disorder, affecting millions of people and rapidly increasing over the last decades. Even though there is no intervention yet to stop the neurodegenerative pathology, many efficient treatment methods are available, including for patients with advanced PD. Neuroplasticity is a fundamental property of the human brain to adapt both to external changes and internal insults and pathological processes. In this paper we examine the current knowledge and concepts concerning changes at network level, cellular level and molecular level as parts of the neuroplastic response to protein aggregation pathology, synapse loss and neuronal loss in PD. We analyse the beneficial, compensatory effects, such as augmentation of nigral neurons efficacy, as well as negative, maladaptive effects, such as levodopa-induced dyskinesia. Effects of physical activity and different treatments on neuroplasticity are considered and the opportunity of biomarkers identification and use is discussed.