bluuebunny/crossref_metadata_2025 huggingface dataset:
A parameter extraction method for InP HBT small‐signal model considering emitter–collector laminated capacitance effect
Authors: Su Xiang , Mao Shuman , Wang Yutong , Tang Min , Yan Bo , Xu Yuehang
Published: August 2024

The extraction of small‐signal parameters is of great importance for the modeling of InP heterojunction bipolar transistors (HBTs). This letter proposes an improved small‐signal parameter extraction method that considers both the emitter–collector capacitance effect and the current crowding effect. The corresponding parameter extraction procedure based on closed‐form equations is outlined. Furthermore, the model parameter extraction method is validated using two different‐sized InP HBT devices with multibias S‐parameters. The results demonstrate that the established small‐signal model exhibits greater than 90% accuracy across the frequency range of 1–110 GHz. In particular, in the high‐frequency band (above 50 GHz), the proposed model exhibits an improvement in accuracy of 7.4% after considering the emitter–collector capacitance and current crowding effects. This method can contribute to accurate modeling of the noise and large‐signal performance of InP HBT.
Design and validation of a novel 2.5‐D miniaturized FSS with angular and superior polarization stability for mobile technology
Authors: Li Yan , Wang Pei , Xu Shaojie , Yu Guoliang , Qiu Yang , Zhu Mingmin , Zhou Haomiao , Li Erping
Published: August 2024

This paper presents a novel 2.5D miniaturized frequency‐selective surface (FSS) measuring 6.1 mm × 6.1 mm, designed to effectively shield smartphones and tablets from unwanted electromagnetic radiation. The FSS is notable for its stable attenuation peaks in the high‐frequency stopband under transverse magnetic (TM) polarization, offering dual‐frequency response and exceptional angular stability in both transverse electric and TM modes. An equivalent circuit analysis, prototype fabrication, and empirical evaluation confirmed its effectiveness. The prototype exhibits superior polarization stability and minimal peak attenuation reduction of just 1.9 dB (10%) across a 0°–60° incidence angle, outperforming similar studies.
LET‐based approximation of the microdosimetric kinetic model for proton radiotherapy
Authors: Parisi Alessio , Furutani Keith M. , Sato Tatsuhiko , Beltran Chris J.
Published: August 2024

Background

Phenomenological relative biological effectiveness (RBE) models for proton therapy, based on the dose‐averaged linear energy transfer (LET), have been developed to address the apparent RBE increase towards the end of the proton range. The results of these phenomenological models substantially differ due to varying empirical assumptions and fitting functions. In contrast, more theory‐based approaches are used in carbon ion radiotherapy, such as the microdosimetric kinetic model (MKM). However, implementing microdosimetry‐based models in LET‐based proton therapy treatment planning systems poses challenges.

Purpose

This work presents a LET‐based version of the MKM that is practical for clinical use in proton radiotherapy.

Methods

At first, we derived an approximation of the Mayo Clinic Florida (MCF) MKM for relatively‐sparsely ionizing radiation such as protons. The mathematical formalism of the proposed model is equivalent to the original MKM, but it maintains some key features of the MCF MKM, such as the determination of model parameters from measurable cell characteristics. Subsequently, we carried out Monte Carlo calculations with PHITS in different simulated scenarios to establish a heuristic correlation between microdosimetric quantities and the dose averaged LET of protons.

Results

A simple allometric function was found able to describe the relationship between the dose‐averaged LET of protons and the dose‐mean lineal energy, which includes the contributions of secondary particles. The LET‐based MKM was used to model the in vitro clonogenic survival RBE of five human and rodent cell lines (A549, AG01522, CHO, T98G, and U87) exposed to pristine and spread‐out Bragg peak (SOBP) proton beams. The results of the LET‐based MKM agree well with the biological data in a comparable or better way with respect to the other models included in the study. A sensitivity analysis on the model results was also performed.

Conclusions

The LET‐based MKM integrates the predictive theoretical framework of the MCF MKM with a straightforward mathematical description of the RBE based on the dose‐averaged LET, a physical quantity readily available in modern treatment planning systems for proton therapy.
Characterizing devices for validation of dose, dose rate, and LET in ultra high dose rate proton irradiations
Authors: Harrison Nathan , Charyyev Serdar , Oancea Cristina , Stanforth Alexander , Gelover Edgar , Zhou Shuang , Dynan William S , Zhang Tiezhi , Biegalski Steven , Lin Liyong
Published: August 2024

Background

Ultra high dose rate (UHDR) radiotherapy using ridge filter is a new treatment modality known as conformal FLASH that, when optimized for dose, dose rate (DR), and linear energy transfer (LET), has the potential to reduce damage to healthy tissue without sacrificing tumor killing efficacy via the FLASH effect.

Purpose

Clinical implementation of conformal FLASH proton therapy has been limited by quality assurance (QA) challenges, which include direct measurement of UHDR and LET. Voxel DR distributions and LET spectra at planning target margins are paramount to the DR/LET‐related sparing of organs at risk. We hereby present a methodology to achieve experimental validation of these parameters.

Methods

Dose, DR, and LET were measured for a conformal FLASH treatment plan involving a 250‐MeV proton beam and a 3D‐printed ridge filter designed to uniformly irradiate a spherical target. We measured dose and DR simultaneously using a 4D multi‐layer strip ionization chamber (MLSIC) under UHDR conditions. Additionally, we developed an “under‐sample and recover (USRe)” technique for a high‐resolution pixelated semiconductor detector, Timepix3, to avoid event pile‐up and to correct measured LET at high‐proton‐flux locations without undesirable beam modifications. Confirmation of these measurements was done using a MatriXX PT detector and by Monte Carlo (MC) simulations.

Results

MC conformal FLASH computed doses had gamma passing rates of >95% (3 mm/3% criteria) when compared to MatriXX PT and MLSIC data. At the lateral margin, DR showed average agreement values within 0.3% of simulation at 100 Gy/s and fluctuations ∼10% at 15 Gy/s. LET spectra in the proximal, lateral, and distal margins had Bhattacharyya distances of <1.3%.

Conclusion

Our measurements with the MLSIC and Timepix3 detectors shown that the DR distributions for UHDR scenarios and LET spectra using USRe are in agreement with simulations. These results demonstrate that the methodology presented here can be used effectively for the experimental validation and QA of FLASH treatment plans.
Patient perceptions of success in obesity treatment: An IMI2 SOPHIA study
Authors: Farrell E. , Nadglowski J. , Hollmann E. , le Roux C. W. , McGillicuddy D.
Published: August 2024

Background

It is anticipated that by 2030, 20% of the world's population will live with obesity. Success in the management of obesity is predominately determined in terms of BMI or percentage weight loss, yet the limitations of these have been widely recognized. This study aimed to understand patient definitions of success in obesity treatment.

Methods

A series of in‐depth focus groups, carried out with n = 30 adults living with obesity, offered a qualitative insight into patient definitions of success.

Results

A thematic analysis of data yielded four thematic findings: Success as freedom from stigma, bias and the mental burden of obesity; success as being able to participate fully in the world; success as measured by NSVs [non‐scale victories]; and success is not a number on a scale.

Conclusions

What this study highlights is (1) how current measures of success do not accurately encompass the priorities of people living with obesity, (2) the importance of addressing the psychological and emotional aspects of living with obesity in any definition of success , and (3) the importance of meaningful co‐creation of goals and indicators of success between clinician and patient for the effective management of the disease of obesity.
The medical and functional burden of surviving childhood ependymoma: A population‐based study in Ontario, Canada
Authors: Coltin Hallie , Pequeno Priscila , Liu Ning , Tsang Derek S. , Gupta Sumit , Taylor Michael D. , Bouffet Eric , Ramaswamy Vijay , Nathan Paul C.
Published: August 2024

Background

Few studies have characterized the burden of late effects among childhood ependymoma survivors. To address this gap, we examined these sequelae using real‐world health services data in a population‐based ependymoma survivor cohort.

Methods

All individuals younger than 18 years diagnosed with an ependymoma in Ontario, Canada between 1987 and 2015 who had survived at least 5 years from their latest pediatric cancer event (index date) were matched 1:5 with population controls. Following linkage with provincial health services data, the cumulative incidences of multiple medical and functional outcomes between survivors and controls were compared.

Results

Among 96 survivors, 77.1% had been irradiated and 9.4% had received cisplatin. At 10 years post‐index, survivors were at significantly higher risk of all‐cause mortality (7.1%, 95% confidence interval [CI]: 1.0–13.3 vs. 0.3%, 95% CI: 0.0–1.0; p = .0002), non‐obstetric hospitalization (45.1%, 95% CI: 32.6–56.7 vs. 10.6%, 95% CI: 7.6–14.1; p < .0001), stroke (6.5%, 95% CI: 2.3–13.7 vs. 0%; p < .0001), severe hearing loss requiring an amplification device (7.5%, 95% CI: 2.7–15.7 vs. 0%; p < .0001), receiving homecare service (27.6%, 95% CI: 18.5–37.5 vs. 7.7%, 95% CI: 5.3–10.7; p < .0001), and submitting a disability support prescription claim (24.0%, 95% CI: 14.8–34.3 vs. 5.4%, 95% CI: 3.5–7.8; p < .0001) compared to controls.

Conclusions

Pediatric ependymoma survivors are highly vulnerable to severe late sequelae, including death, stroke, severe hearing loss, and disability. Urgent efforts are needed to improve risk‐stratification approaches that mitigate exposure to toxic therapies for children with lower risk disease. Interventions to prevent or decrease the risk of developing late sequelae are critical to optimizing survivor long‐term health.
Exploring the role of pain on physical activity among youth with acute lymphoblastic leukemia using the biopsychosocial model
Authors: van Asselt Anna E. , Gibler Robert C. , Tokala Meghan , Dreyer Gillette Meredith L. , Klages Kimberly L. , Gilbert Renee , Weber Jacee , Bates Carolyn R.
Published: August 2024

Background

Engaging in physical activity (PA) throughout cancer treatment offers many benefits, but may be challenging due to cancer‐related pain. Pain research in pediatric cancer has primarily focused on procedural pain, with fewer studies exploring how pain affects PA. The current study qualitatively investigated the impact of pain on PA in youth with acute lymphoblastic leukemia (ALL) using a biopsychosocial framework.

Procedure

As part of a larger study, caregivers (N = 17) of a child diagnosed with ALL and on treatment for less than 1 year completed a semi‐structured interview about perceptions of their child's health behaviors during ALL treatment. This secondary analysis focused specifically on discussions about pain and its impact on PA. We followed Braun and Clarke's (2006) six‐step thematic analysis framework to identify themes of pain‐related barriers to PA.

Results

Key pain‐related barriers endorsed by caregivers included: interactions among pain and treatment effects, caregiver distress around seeing their child in pain, and fear of interfering with medical equipment. Despite these barriers, caregivers found creative solutions to adapt activities for their child. Caregivers were reassured by PA advice from their medical team; however, advice varied between teams.

Conclusion

The relationship between pain and PA during ALL treatment is influenced by an intricate system of biological (e.g., treatment effects), psychological (e.g., parental distress), and social (e.g., communication among families and medical teams) factors. Future directions include identifying evidence‐based PA recommendations and exploring family–team communication dynamics. This study also highlights a need to prioritize ALL pain management and involve caregivers in behavioral treatment protocols to improve PA.
Management of neonatal and infant aortic thrombosis: A single‐center case series
Authors: Lapite Ajibike , Abu‐Arja Mohammad H. , Han Hyojeong , Lee‐Kim YoungNa , Sartain Sarah E. , Cohen Clay T.
Published: August 2024

Neonatal and infant aortic thrombosis is a rare albeit life‐threatening thrombotic event, particularly seen in premature infants with an arterial catheter in place. We describe our institutional experience and approach to the management of 11 infants with occlusive or nearly occlusive aortic thrombosis. We observed at least partial thrombus resolution in all patients. Complications related to our management included minor bleeding in two children receiving thrombolytic therapy, and two major bleeding events in children receiving anticoagulation alone. Our experience adds to the growing body of evidence that thrombolysis and thrombectomy should be considered in managing neonatal/infant aortic thrombosis.
Analogs of Cyclic Peptide Mortiamide‐D From Marine Fungi Have Improved Membrane Permeability and Kill Drug‐Resistant Melanoma Cells
Authors: Bergeron Catherine , Bérubé Christopher , Lamb Henry , Koda Yasuko , Craik David J. , Henriques Sónia Troeira , Voyer Normand , Lawrence Nicole
Published: August 2024

Targeted melanoma therapies, including treatment with the small molecule drug dabrafenib, can become ineffective due to acquired drug resistance. Dabrafenib targets BRAF‐V600E, a mutation that is present in more than half of melanoma cancers. Therefore, drug discovery efforts need to explore alternative candidate molecules that selectively target and kill melanoma cells via mechanisms different to those of current drugs. Marine fungi are an underexplored resource for bioactive molecules. Mortiamide‐D, a seven amino acid cyclic peptide from Mortierella sp, is an example molecule with desirable features for drug development. We synthesized mortiamide‐D and three rationally designed analogs and observed modest micromolar activity against HT144 melanoma cells that are sensitive or resistant to dabrafenib. By contrast, mortiamide‐D and analogs did not kill noncancer HaCaT cells at these concentrations. Substitution of D‐Ile at position 7 with D‐Arg improved membrane permeability and enhanced potency against HT144 cells via a mode‐of‐action that includes perturbation of mitochondrial membrane potential. These studies suggest the potential of mortiamides as modifiable scaffolds for developing a new class of molecule for targeting melanoma cells.
Improving Process Hazard Analysis (PHA) outcomes to better manage critical controls in mining industry: From PHA to verification in the field
Authors: Catala Christophe , Anato Laura , Carrero Luis , Morar Catherine
Published: August 2024

Process safety management in the mining and metals industry is relatively new compared to other high‐hazard process industries such as oil and gas or chemicals. Practices are less mature and are developing, transferring from other industries, and using the International Council on Mining and Metals (ICMM) guidance to manage critical controls. This paper shares how Rio Tinto, a leading mining and metals company, has improved its critical controls management practices. Focus is put on how the company has improved the quality of its process hazard analyses (PHAs) and critical controls management activities through a series of actions. This covers clarification of the methodology used, development of training packages, revision of the methodology used to identify critical controls, development of a PHA facilitation approval process and a PHA facilitation approval committee, implementation of a training and coaching program for internal candidates, and development of assurance activities to monitor effectiveness of the process. These actions have resulted in very encouraging results in terms of overall quality of the PHAs, effectiveness of the PHA approval process to support the new methodologies introduced, and the development of internal facilitation capabilities.
Crossing river oil pipeline spill emergency response plan automatic association study based on Apriori‐Topsis
Authors: Kang Jian , Meng Xiangxuan , Li Ningning , Su Tao , Zhang Xiangyu , Dai Haoyuan
Published: August 2024

With the increase in service time of oil pipelines, the probability of pipeline damage increases and the risk of leakage increases. However, as an important equipment for transporting oil, long‐distance pipelines have to be built across rivers. According to statistics, the leakage accidents of oil pipelines crossing rivers account for nearly 50% of all pipeline leakage accidents. Crude oil diffused into rivers easily cause serious pollution and damage to rivers and nearby organisms. Therefore, it is of great significance to study a reasonable, rapid, and efficient oil spill emergency treatment scheme for pollution and property loss. In this paper, an optimization model of emergency disposal scheme based on Apriori‐Topsis is proposed. Firstly, according to the characteristics of the oil spill pipeline, the general scheme library of emergency disposal is automatically generated by association rules, including the type, quantity, layout, and selected disposal technology of oil recovery equipment. Then, combined with the calculation of emergency disposal materials, the multi‐decision technology Topsis model is adopted to optimize the scheme from two angles of oil recovery effect and economic cost, and finally the cost‐effective emergency disposal scheme is obtained. Finally, taking the oil pollution accident on the second line of the Qing river as an example, the optimization model of emergency disposal scheme based on Apriori‐Topsis proposed in this paper is carried out. The application results verify the availability and effectiveness of the model, which provides a new method for the selection of emergency materials for rivers and pipeline process safety.
On Wrist and Forearm Pain Experienced by Rowers: Can Mechanical Metamaterials Make Rowing and Coastal Rowing Safer?
Authors: Grima Joseph N. , Cerasola Dario , Grima‐Cornish James N. , Vella Wood Michelle , Portelli Nadia , Sillato Darren , Casha Marilyn , Gatt Alfred , Agius Tonio P. , Formosa Cynthia , Attard Daphne
Published: August 2024

On‐water rowing is a sport where participants make extensive, powerful, and complex repetitive movements with their wrists to pull and feather (twist) the oar. Herein, the aim is to assess the frequency and perceived causes of wrist and forearm pain in rowers and, in particular, assess whether there are any possible mechanical issues that could be addressed through the use of auxetic technology. Through an online survey of 145 on‐water rowers, it is found that 33.8% of the rowers reported wrist or forearm pain arising from rowing. The majority (67.3%) consider over‐gripping to be the cause while one out of five associated it with periods of tension and anxiety, which also led them to over‐grip. This indicates that rowing handles could benefit from the use of mechanical metamaterials, auxetics in particular, owing to their anomalous manner in how they deform when subjected to mechanical deformations. Moreover, given the rise in popularity of coastal rowing, which will become an Olympic discipline alongside classic rowing as from the 2028 Los Angeles Olympic Games, the potential use of auxetics in the manufacture of protective gear for use in coastal rowing is also discussed.
Harmine promotes megakaryocyte differentiation and thrombopoiesis by activating the Rac1/Cdc42/JNK pathway through a potential target of 5‐HTR2A
Authors: Liu Xiaoxi , Lai Jia , Zhang Xiaoqin , Wu Anguo , Zhou Ling , Li Yueyue , Huang Qianqian , Huang Xinwu , Li Hua , Lan Cai , Liu Jian , Huang Feihong , Wu Jianming
Published: August 2024

Harmine (HM), a β‐carboline alkaloid extracted from plants, is a crucial component of traditional Chinese medicine (TCM) known for its diverse pharmacological activities. Thrombocytopenia, a common and challenging hematological disorder, often coexists with serious illnesses. Previous research has shown a correlation between HM and thrombocytopenia, but the mechanism needs further elucidation. The aim of this study was to clarify the mechanisms underlying the effects of HM on thrombocytopenia and to develop new therapeutic strategies. Flow cytometry, Giemsa staining, and Phalloidin staining were used to assess HM's impact on Meg‐01 and HEL cell differentiation and maturation in vitro. A radiation‐induced thrombocytopenic mouse model was employed to evaluate HM's effect on platelet production in vivo. Network pharmacology, molecular docking, and protein blotting were utilized to investigate HM's targets and mechanisms. The results demonstrated that HM dose‐dependently promoted Meg‐01 and HEL cell differentiation and maturation in vitro and restored platelet levels in irradiated mice in vivo. Subsequently, HM was found to be involved in the biological process of platelet production by upregulating the expressions of Rac1, Cdc42, JNK, and 5‐HTR2A. Furthermore, the targeting of HM to 5‐HTR2A and its correlation with downstream Rac1/Cdc42/JNK were also confirmed. In conclusion, HM regulates megakaryocyte differentiation and thrombopoiesis through the 5‐HTR2A and Rac1/Cdc42/JNK pathways, providing a potential treatment strategy for thrombocytopenia.
Biowaxes Used as a Barrier Formulation Material in Coating Fibre‐Based Substrates
Authors: Li Sai , Svedström Kirsi , Lepo Anneli
Published: August 2024

Recently, replacing plastic packaging materials with biobased alternatives has been trending in the field of food packaging. The role of food packaging materials is to contain and protect the product throughout the supply chain, and the most used materials for this are polyolefins due to their functionality and affordability. However, environmental awareness and the new regulations and restrictions have been strong drivers to push the development towards biobased materials. In this study, the feasibility and potential of biowaxes used as a dispersion barrier coating formulation material were examined. Four commercial biowaxes were selected for the study, and their nano‐ and crystalline structures were determined by wide‐angle X‐ray scattering (WAXS). The biowaxes were melted and dispersed into a stable water‐based dispersion. Barrier coating formulations were prepared using two different polymer dispersions mixed with the waxes and additives. A fibre substrate was coated with the prepared formulations, and their barrier properties were studied. The properties of biowax‐containing coatings showed similar or minor improvements compared to the reference. However, foldability was especially improved in the biowax sample. Interestingly, this sample contained wax, which was structurally most stable, presenting an orthorhombic phase in all studied states. Based on our results, introducing biowax materials is a viable solution to replace part of the formulation materials and adjust the barrier performance of existing dispersion polymers. Our results also suggest that the nanostructure of waxes might play a role in an optimal solution. However, all these observations deserve more studies, and the share of biowax in barrier coatings will need further optimisation in the future.
Leveraging the next generation of spaceborne Earth observations for fuel monitoring and wildland fire management
Authors: Leite Rodrigo V. , Amaral Cibele , Neigh Christopher S. R. , Cosenza Diogo N. , Klauberg Carine , Hudak Andrew T. , Aragão Luiz , Morton Douglas C. , Coffield Shane , McCabe Tempest , Silva Carlos A.
Published: August 2024

Managing fuels is a key strategy for mitigating the negative impacts of wildfires on people and the environment. The use of satellite‐based Earth observation data has become an important tool for managers to optimize fuel treatment planning at regional scales. Fortunately, several new sensors have been launched in the last few years, providing novel opportunities to enhance fuel characterization. Herein, we summarize the potential improvements in fuel characterization at large scale (i.e., hundreds to thousands of km2) with high spatial and spectral resolution arising from the use of new spaceborne instruments with near‐global, freely‐available data. We identified sensors at spatial resolutions suitable for fuel treatment planning, featuring: lidar data for characterizing vegetation structure; hyperspectral sensors for retrieving chemical compounds and species composition; and dense time series derived from multispectral and synthetic aperture radar sensors for mapping phenology and moisture dynamics. We also highlight future hyperspectral and radar missions that will deliver valuable and complementary information for a new era of fuel load characterization from space. The data volume that is being generated may still challenge the usability by a diverse group of stakeholders. Seamless cyberinfrastructure and community engagement are paramount to guarantee the use of these cutting‐edge datasets for fuel monitoring and wildland fire management across the world.
Biomedical Utility of Non‐Enzymatic DNA Amplification Reaction: From Material Design to Diagnosis and Treatment
Authors: Chen Ye , Liu Zhiqiang , Zhang Bowen , Wu Haoyan , Lv Xiaoying , Zhang Yuxin , Lin Yunfeng
Published: August 2024

Nucleic acid nanotechnology has become a promising strategy for disease diagnosis and treatment, owing to remarkable programmability, precision, and biocompatibility. However, current biosensing and biotherapy approaches by nucleic acids exhibit limitations in sensitivity, specificity, versatility, and real‐time monitoring. DNA amplification reactions present an advantageous strategy to enhance the performance of biosensing and biotherapy platforms. Non‐enzymatic DNA amplification reaction (NEDAR), such as hybridization chain reaction and catalytic hairpin assembly, operate via strand displacement. NEDAR presents distinct advantages over traditional enzymatic DNA amplification reactions, including simplified procedures, milder reaction conditions, higher specificity, enhanced controllability, and excellent versatility. Consequently, research focusing on NEDAR‐based biosensing and biotherapy has garnered significant attention. NEDAR demonstrates high efficacy in detecting multiple types of biomarkers, including nucleic acids, small molecules, and proteins, with high sensitivity and specificity, enabling the parallel detection of multiple targets. Besides, NEDAR can strengthen drug therapy, cellular behavior control, and cell encapsulation. Moreover, NEDAR holds promise for constructing assembled diagnosis‐treatment nanoplatforms in the forms of pure DNA nanostructures and hybrid nanomaterials, which offer utility in disease monitoring and precise treatment. Thus, this paper aims to comprehensively elucidate the reaction mechanism of NEDAR and review the substantial advancements in NEDAR‐based diagnosis and treatment over the past five years, encompassing NEDAR‐based design strategies, applications, and prospects.
Rolling up 2D WSe2 Nanosheets to 1D Anisotropic Nanoscrolls for Polarization‐Sensitive Photodetectors
Authors: Ao Zhikang , Liu Chang , Ma Huifang , Lan Xiang , Zhang Jianhong , Zhang Baihui , Zhang Fen , Wang Zeran , Chen Peng , Zhong Mianzeng , Wang Guang , Zhang Zhengwei
Published: August 2024

The intrinsic low‐symmetry crystal structures or external geometries of low‐dimensional materials are crucial for polarization‐sensitive photodetection. However, these inherently anisotropic materials are limited in variety, and their anisotropy is confined to specific crystal directions. Transforming 2D semiconductors, such as WSe2, from isotropic 2D nanosheets into anisotropic 1D nanoscrolls expands their application in polarization photodetection. Despite this considerable potential, research on polarization photodetection based on nanoscrolls remains scarce. Here, the uniform crystalline orientation of WSe2 nanoscrolls is achieved conveniently and efficiently by applying ethanol droplets to vapor deposition‐grown bilayer WSe2 nanosheets. Angle‐resolved polarized Raman spectroscopy of WSe2 nanoscrolls demonstrates vibrational anisotropy. Photodetectors based on these nanoscrolls show competitive overall performance with a broadband detection range from 405 to 808 nm, a competitive on/off ratio of ≈900, a high detectivity of 3.4 × 108 Jones, and a fast response speed of ≈30 ms. Additionally, WSe2 nanoscroll‐based photodetectors exhibit strong polarization‐sensitive detection with a maximum dichroic ratio of 1.5. More interestingly, due to high photosensitivity, the WSe2 nanoscroll detectors can easily record sequential puppy images. This work reveals the potential of WSe2 nanoscrolls as excellent polarization‐sensitive photodetectors and provides new insights into the development of high‐performance optoelectronic devices.
All‐Metal Flexible Fiber by Continuously Assembling Nanowires for High Electrical Conductivity
Authors: Tang Chengqiang , Zhang Kailin , Yu Sihui , Guan Hang , Cao Mingjie , Zhang Kun , Pan You , Zhang Songlin , Sun Xuemei , Peng Huisheng
Published: August 2024

Fiber electronics booms as a new important field but is currently limited by the challenge of finding both highly flexible and conductive fiber electrodes. Here, all‐metal fibers based on nanowires are discovered. Silver nanowires are continuously assembled into robust fibers by salt‐induced aggregation and then firmly stabilized by plasmonic welding. The nanowire network structures provide them both high flexibility with moduli at the level of MPa and conductivities up to 106 S m−1. They also show excellent electrochemical properties such as low impedance and high electrochemically active surface area. Their stable chronic single‐neuron recording is further demonstrated with good biocompatibility in vivo. These new fiber materials may provide more opportunities for the future development of fiber electronics.
$$ \mathcal{N} $$ = 2 superconformal higher-spin multiplets and their hypermultiplet couplings
Authors: Buchbinder Ioseph , Ivanov Evgeny , Zaigraev Nikita
Published: August 2024

Abstract

We construct an off-shell $$ \mathcal{N} $$
N
= 2 superconformal cubic vertex for the hypermultiplet coupled to an arbitrary integer higher spin s gauge $$ \mathcal{N} $$
N
= 2 supermultiplet in a general $$ \mathcal{N} $$
N
= 2 conformal supergravity background. We heavily use $$ \mathcal{N} $$
N
= 2, 4D harmonic superspace that provides an unconstrained superfield Lagrangian description. We start with $$ \mathcal{N} $$
N
= 2 global superconformal symmetry transformations of the free hypermultiplet model and require invariance of the cubic vertices of general form under these transformations and their gauged version. As a result, we deduce $$ \mathcal{N} $$
N
= 2, 4D unconstrained analytic superconformal gauge potentials for an arbitrary integer s. These are the basic ingredients of the approach under consideration. We describe the properties of the gauge potentials, derive the corresponding superconformal and gauge transformation laws, and inspect the off-shell contents of the thus obtained $$ \mathcal{N} $$
N
= 2 superconformal higher-spin s multiplets in the Wess-Zumino gauges. The spin s multiplet involves 8(2s− 1)B + 8(2s− 1)F essential off-shell degrees of freedom. The cubic vertex has the generic structure higher spin gauge superfields × hypermultiplet supercurrents. We present the explicit form of the relevant supercurrents.
Characterization of the PADME positron beam for the X17 measurement
Authors:   The PADME collaboration, Bertelli S. , Bossi F. , Buonomo B. , De Sangro R. , Di Giulio C. , Di Meco E. , Dimitrova K. , Domenici D. , Ferrarotto F. , Finocchiaro G. , Foggetta L. G. , Frankenthal A. , Garattini M. , Georgiev G. , Gianotti P. , Ivanov S. , Ivanov Sv. , Kozhuharov V. , Leonardi E. , Long E. , Mancini M. , Organtini G. C. , Raggi M. , Sarra I. , Simeonov R. , Spadaro T. , Spiriti E. , Valente P. , Variola A. , Vilucchi E.
Published: August 2024

Abstract

This paper presents a detailed characterization of the positron beam delivered by the Beam Test Facility at Laboratori Nazionali of Frascati to the PADME experiment during Run III, which took place from October to December 2022. It showcases the methodology used to measure the main beam parameters such as the position in space, the absolute momentum scale, the beam energy spread, and its intensity through a combination of data analysis and Monte Carlo simulations. The results achieved include an absolute precision in the momentum of the beam to within ~1–2 MeV/c, a relative beam energy spread below 0.25%, and an absolute precision in the intensity of the beam at the level of 2%.
Can you hear the Planck mass?
Authors: De Luca G. Bruno , De Ponti Nicolò , Mondino Andrea , Tomasiello Alessandro
Published: August 2024

Abstract

For the Laplacian of an n-Riemannian manifold X, the Weyl law states that the k-th eigenvalue is asymptotically proportional to (k/V)2/n, where V is the volume of X. We show that this result can be derived via physical considerations by demanding that the gravitational potential for a compactification on X behaves in the expected (4+n)-dimensional way at short distances. In simple product compactifications, when particle motion on X is ergodic, for large k the eigenfunctions oscillate around a constant, and the argument is relatively straightforward. The Weyl law thus allows to reconstruct the four-dimensional Planck mass from the asymptotics of the masses of the spin 2 Kaluza-Klein modes. For warped compactifications, a puzzle appears: the Weyl law still depends on the ordinary volume V, while the Planck mass famously depends on a weighted volume obtained as an integral of the warping function. We resolve this tension by arguing that in the ergodic case the eigenfunctions oscillate now around a power of the warping function rather than around a constant, a property that we call weighted quantum ergodicity. This has implications for the problem of gravity localization, which we discuss. We show that for spaces with Dp-brane singularities the spectrum is discrete only for p = 6, 7, 8, and for these cases we rigorously prove the Weyl law by applying modern techniques from RCD theory.
Noncommutative gauge symmetry in the fractional quantum Hall effect
Authors: Du Yi-Hsien , Mehta Umang , Son Dam Thanh
Published: August 2024

Abstract

We show that a system of particles on the lowest Landau level can be coupled to a probe U(1) gauge field $$ \mathcal{A} $$
A
μ in such a way that the theory is invariant under a noncommutative U(1) gauge symmetry. While the temporal component $$ \mathcal{A} $$
A
0 of the probe field is coupled to the projected density operator, the spatial components $$ \mathcal{A} $$
A
i are best interpreted as quantum displacements, which distort the interaction potential between the particles. We develop a Seiberg-Witten-type map from the noncommutative U(1) gauge symmetry to a simpler version, which we call “baby noncommutative” gauge symmetry, where the Moyal brackets are replaced by the Poisson brackets. The latter symmetry group is isomorphic to the group of volume preserving diffeomorphisms. By using this map, we resolve the apparent contradiction between the noncommutative gauge symmetry, on the one hand, and the particle-hole symmetry of the half-filled Landau level and the presence of the mixed Chern-Simons terms in the effective Lagrangian of the fractional quantum Hall states, on the other hand. We outline the general procedure which can be used to write down effective field theories which respect the noncommutative U(1) symmetry.
More axion stars from strings
Authors: Gorghetto Marco , Hardy Edward , Villadoro Giovanni
Published: August 2024

Abstract

We show that if dark matter consists of QCD axions in the post-inflationary scenario more than ten percent of it efficiently collapses into Bose stars at matter-radiation equality. Such a result is mostly independent of the present uncertainties on the axion mass. This large population of solitons, with asteroid masses and Earth-Moon distance sizes, might plausibly survive until today, with potentially interesting implications for phenomenology and experimental searches.
Graph Hörmander Systems
Authors: Li Haojian , Junge Marius , LaRacuente Nicholas
Published: August 2024

This paper extends the Bakry-Émery criterion relating the Ricci curvature and logarithmic Sobolev inequalities to the noncommutative setting. We obtain easily computable complete modified logarithmic Sobolev inequalities of graph Laplacians and Lindblad operators of the corresponding graph Hörmander systems. We develop the anti-transference principle stating that the matrix-valued modified logarithmic Sobolev inequalities of sub-Laplacian operators on a compact Lie group are equivalent to such inequalities of a family of the transferred Lindblad operators with a uniform lower bound.
Non-coercive Neumann Boundary Control Problems
Authors: Apel Thomas , Mateos Mariano , Rösch Arnd
Published: August 2024

The article examines a linear-quadratic Neumann control problem that is governed by a non-coercive elliptic equation. Due to the non-self-adjoint nature of the linear control-to-state operator, it is necessary to independently study both the state and adjoint state equations. The article establishes the existence and uniqueness of solutions for both equations, with minimal assumptions made about the problem’s data. Next, the regularity of these solutions is studied in three frameworks: Hilbert–Sobolev spaces, Sobolev–Slobodeckiĭ spaces, and weighted Sobolev spaces. These regularity results enable a numerical analysis of the finite element approximation of both the state and adjoint state equations. The results cover both convex and non-convex domains and quasi-uniform and graded meshes. Finally, the optimal control problem is analyzed and discretized. Existence and uniqueness of the solution, first-order optimality conditions, and error estimates for the finite element approximation of the control are obtained. Numerical experiments confirming these results are included.
New Asymptotic Evaluations for Sequences of Linear Positive Operators on $$C_{2\pi }\left( {{\mathbb {R}}}\right) $$
Authors: Popa Dumitru
Published: August 2024

In the paper we give new asymptotic evaluations for sequences of linear positive operators $$V_{n}:C_{2\pi }\left( {{\mathbb {R}}}\right) \rightarrow C_{2\pi }\left( {{\mathbb {R}}}\right) $$

V
n

:

C

2
π

R

→

C

2
π

R

. Our method of the proof is entirely different than those known in this area. As applications we complete and extend known asymptotic evaluations in this topic.
Audio-biofeedback versus the scale method for improving partial weight-bearing adherence in healthy older adults: a randomised trial
Authors: von Aesch Arlene Vivienne , Häckel Sonja , Kämpf Tobias , Baur Heiner , Bastian Johannes Dominik
Published: August 2024

Purpose

To investigate how audio-biofeedback during the instruction of partial weight-bearing affected adherence, compared to traditional methods, in older adults; and to investigate the influence of individual characteristics.

Methods

The primary outcome measure of this randomised controlled trial was the amount of load, measured as the ground reaction force, on the partial weight-bearing leg. The secondary outcome was the influence of individual characteristics on the amount of load. Included were healthy volunteers 60 years of age or older without gait impairment. Participants were randomly allocated to one of two groups; blinding was not possible. Partial weight-bearing of 20 kg was trained using crutches with audio-biofeedback (intervention group) or a bathroom scale (control group). The degree of weight-bearing was measured during six activities with sensor insoles. A mean load between 15 and 25 kg was defined as adherent.

Results

There was no statistically significant difference in weight-bearing between the groups for all activities measured. For the sit-stand-sit activity, weight-bearing was within the adherence range of 15–25 kg (audio-biofeedback: 21.7 ± 16.6 kg; scale: 22.6 ± 13 kg). For standing, loading was below the lower threshold (10 ± 7 vs. 10 ± 10 kg). Weight-bearing was above the upper threshold for both groups for: walking (26 ± 11 vs. 34 ± 16), step-up (29 ± 18 vs. 34 ± 20 kg) and step-down (28 ± 15 vs. 35 ± 19 kg). Lower level of cognitive function, older age, and higher body mass index were correlated with overloading.

Conclusion

Audio-biofeedback delivered no statistically significant benefit over the scale method. Lower cognitive function, older age and higher body mass index were associated with overloading.

Trial registration

Not applicable due not being a clinical trial and due to the cross-sectional design (one measurement point, no health intervention, no change in health of a person).
Deep learning-based image segmentation for defect detection in additive manufacturing: an overview
Authors: Deshpande Sourabh , Venugopal Vysakh , Kumar Manish , Anand Sam
Published: August 2024

Additive manufacturing (AM) applications are rapidly expanding across multiple domains and are not limited to prototyping purposes. However, achieving flawless parts in medical, aerospace, and automotive applications is critical for the widespread adoption of AM in these industries. Since AM is a complex process consisting of multiple interdependent factors, deep learning (DL) approaches are adopted widely to correlate the AM process physics to the part quality. Typically, in AM processes, computer vision-based DL is performed by extracting the machine’s sensor data and layer-wise images through camera-based systems. This paper presents an overview of computer vision-assisted patch-wise defect localization and pixel-wise segmentation methods reported for AM processes to achieve error-free parts. In particular, these deep learning methods localize and segment defects in each layer, such as porosity, melt-pool regions, and spattering, during in situ processes. Further, knowledge of these defects can provide an in-depth understanding of fine-tuning optimal process parameters and part quality through real-time feedback. In addition to DL architectures to identify defects, we report on applications of DL extended to adjust the AM process variables in closed-loop feedback systems. Although several studies have investigated deploying closed-loop systems in AM for defect mitigation, specific challenges exist due to the relationship between inter-dependent process parameters and hardware constraints. We discuss potential opportunities to mitigate these challenges, including advanced segmentation algorithms, vision transformers, data diversity for improved performance, and predictive feedback approaches.
Mono-n-hexyl phthalate: exposure estimation and assessment of health risks based on levels found in human urine samples
Authors: Pirow Ralph , Bernauer Ulrike , Blume Annegret , Cieszynski Adrian , Flingelli Gabriele , Heiland Astrid , Herzler Matthias , Huhse Bettina , Riebeling Christian , Rosenthal Esther , Sy Moustapha , Tietz Thomas , Trubiroha Achim , Luch Andreas
Published: August 2024

Mono-n-hexyl phthalate (MnHexP) is a primary metabolite of di-n-hexyl phthalate (DnHexP) and other mixed side-chain phthalates that was recently detected in urine samples from adults and children in Germany. DnHexP is classified as toxic for reproduction category 1B in Annex VI of Regulation (EC) 1272/2008 and listed in Annex XIV of the European chemical legislation REACH; thereby, its use requires an authorisation. Health-based guidance values for DnHexP are lacking and a full-scale risk assessment has not been carried out under REACH. The detection of MnHexP in urine samples raises questions about the sources of exposure and concerns of consumer safety. Here, we propose the calculation of a provisional oral tolerable daily intake value (TDI) of 63 µg/kg body weight/day for DnHexP and compare it to intake levels corresponding to levels of MnHexP found in urine. The resulting mean intake levels correspond to less than 0.2% of the TDI, and maximum levels to less than 5%. The TDI was derived by means of an approximate probabilistic analysis using the credible interval from benchmark dose modelling of published ex vivo data on reduced foetal testosterone production in rats. Thus, for the dose associated to a 20% reduction in testosterone production, a lower and upper credible interval of 14.9 and 30.0 mg/kg bw/day, respectively, was used. This is considered a conservative approach, since apical developmental endpoints (e.g. changed anogenital distance) were only observed at higher doses. In addition, we modelled various scenarios of the exposure to the precursor substance DnHexP from different consumer products, taking measured contamination levels into account, and estimated systemic exposure doses. Of the modelled scenarios including the application of sunscreen (as a lotion or pump spray), the use of lip balm, and the wearing of plastic sandals, and considering conservative assumptions, the use of DnHexP-contaminated sunscreen was highlighted as a major contributing factor. A hypothetical calculation using conservative assumptions for the latter resulted in a margin of safety in relation to the lower credible interval of 3267 and 1007 for adults and young children, respectively. Most importantly, it was found that only a fraction of the TDI is reached in all studied exposure scenarios. Thus, with regard to the reported DnHexP exposure, a health risk can be considered very unlikely.
Diffeomorphisms of 4-manifolds with boundary and exotic embeddings
Authors: Iida Nobuo , Konno Hokuto , Mukherjee Anubhav , Taniguchi Masaki
Published: August 2024

We define family versions of the invariant of 4-manifolds with contact boundary due to Kronheimer and Mrowka and use these to detect exotic diffeomorphisms of 4-manifolds with boundary. Further, we show the existence of the first example of exotic 3-spheres in a smooth closed 4-manifold with diffeomorphic complements.
Exploring visible spectrum wavelengths in light transmission through wood material
Authors: Boivin Juliette , Teyssieux Damien , Froehly Luc , Girardon Stéphane , Denaud Louis
Published: August 2024

Wood is a multiscale heterogeneous natural composite material with properties depending on its growing conditions and its genetic heritage. This variability is challenging for industries that work to perform homogeneous and reliable products. In industry, different non-destructive testing methods are in use to classify, grade, and select wood products to optimize their usage. Among them, the use of lasers to detect fiber orientation with different wavelengths. This orientation significantly influences the mechanical behavior of wood, including stress limits and stiffness. According to our knowledge, the use of laser diffusion still is limited to grain angle measurement. Our objective in this paper is to realize transmission light scattering maps for wood samples from several wood species (poplar, oak, Douglas fir, beech), and then identify the most suitable wavelength to study light diffusion in wood, depending on the property that will be measured. A supercontinuum laser is used over a wavelength range from 500 to 800 nm, allowing precise adjustment of the wavelengths. It was found that near-infrared light better scatters in the studied wood species than lower wavelength. However, the wavelength that gives the best contrast between earlywood and latewood depends on the sample studied and is not necessarily in the near infrared rays.