bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the sensing characteristics of two‐dimensional material WTe2 to toxic gases HF and Cl2
Authors: Su Shuo , Chen Li , Yang Maoyou , Zhang Mingjian , Wang Junmei , Shi Jiakuo , Zhang Duo , Hou Weimin , Wu Hongping
Published: August 2023

The adsorption characteristics of gas molecules HF and Cl2 on monolayer WTe2 surface are studied by first‐principles calculation method. The results show that monolayer WTe2 is more sensitive to gas molecule Cl2. The adsorption performance of monolayer WTe2 to gas molecule HF cannot be improved by doping atoms. When the upward vertical electric field is applied, the sensitivity of monolayer WTe2 to gas molecule Cl2 is improved, and when the downward vertical electric field is applied, the monolayer WTe2 shows an obvious desorption trend to gas molecule Cl2. The vertical electric field cannot significantly enhance the interaction between gas molecule HF and Ag‐doped monolayer WTe2. Our research confirms that monolayer WTe2 is more sensitive to gas molecule Cl2 and can be improved or desorbed by the vertical electric field, while that of monolayer WTe2 for gas molecule HF cannot significantly change. Furthermore, the electrical transport characteristics of monolayer WTe2 and Cl2‐WTe2 system are studied to better explain the reason for the higher sensitivity to gas molecule Cl2. The research results of this paper provide theoretical guidance for the experimental preparation of high sensitivity gas sensor based on two‐dimensional transition metal dichalcogenide WTe2.
Mixed Micellization of Promazine Hydrochloride with Cholinium‐Based Anionic Surface Active Ionic Liquids and their Potential Application for the Synthesis of Silver Nanoparticles
Authors: Arif Rabia , Dhanagar Arun , Shaheen Arifa
Published: August 2023

This work is aimed to study the interaction of an amphiphilic drug, promazine hydrochloride (PMZ) and two anionic surface active ionic liquids (SAILs), cholinium laurylsarcosinate [Cho][Sar] and cholinium deoxycholate [Cho][Doc] using conductivity, UV‐visible spectroscopy and fluorescence techniques. The results obtained by all three techniques indicated non‐ideal behavior and synergistic interactions between the PMZ drug and SAIL mixed systems. Further, the drug‐SAIL mixtures were used to stabilize silver nanoparticles (Ag NPs) in aqueous solution. The results of UV‐visible spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM) showed that PMZ and SAILs had strong electrostatic and hydrophobic interactions which played a significant role in the stabilization of Ag NPs. The morphological analysis of the Ag NPs showed the formation of various types of aggregates controlled by the internal packing of PMZ‐[Cho][Sar]/[Cho][Doc] mixed systems. These drug‐SAIL based NPs could be used in separation and synthesis applications in nanotechnology by altering the structure of drugs and SAILs.
Atypical Metal‐Center Coordination in Two Cyanide‐Based Coordination Polymers
Authors: Vázquez Monica C. , Avila Yosuan , Mojica Rodrigo , Ávila Manuel , Reguera Edilso
Published: August 2023

This contribution reports the crystal structure, solved and refined from single crystal XRD data, of two cyanide‐based coordination polymers, with K[Cu2(CN)3] ⋅ H2O (1) and [Cd(H2O)]2Cd(H2O)2[Cu(CN)3Cu(CN)2]2 ⋅ 8H2O (2) as formula units. These coordination polymers are characterized by metal‐metal bonds between copper atoms. In 1, the framework is formed by Cu−Cu(CN)3 pseudo tetrahedral blocks linked by planar Cu2(CN)3 units. In this material, a defined Cu−Cu bond was identified, which is congruent with the corresponding Raman spectrum. The K atom and water molecule occupy the framework cavities. In 2, the Cu−Cu bond is observed in Cu2(CN)6 blocks which remain linked to Cd(NC)2(H2O)4 and Cd(NC)4(H2O)2 units occupying their axial and equatorial coordination positions, respectively. The solid framework is completed by the −N=C−Cu−C=N− chains linked to Cd(NC)4(H2O)2 moieties. The crystal structure for 2 contains two different sites for the metal centers. The structural study was complemented by recording IR, Raman, and UV/Vis spectra. These two coordination polymers behave as semiconductor materials with a band gap of 2.79 and 3.43 eV, respectively, as derived from the Tauc plot of the corresponding UV/Vis spectrum. Band structure calculations properly supported these values. 1 is a material of an indirect band gap, while 2 has a direct band gap.
Mapping Heterogeneity of Pristine and Aged Li‐ and Na‐Mnhcf Cathode by Synchrotron‐Based Energy‐Dependent Full Field Transmission X‐ray Microscopy
Authors: Maisuradze Mariam , Li Min , Mullaliu Angelo , Sorrentino Andrea , Tonti Dino , Passerini Stefano , Giorgetti Marco
Published: August 2023

Manganese hexacyanoferrate is a promising cathode material for lithium and sodium ion batteries, however, it suffers of capacity fading during the cycling process. To access the structural and functional characteristics at the nanometer scale, fresh and cycled electrodes are extracted and investigated by transmission soft X‐ray microscopy, which allows chemical characterization with spatial resolution from position‐dependent x‐ray spectra at the Mn L‐, Fe L‐ and N K‐edges. Furthermore, soft X‐rays prove to show superior sensitivity toward Fe, compare to hard X‐rays. Inhomogeneities within the samples are identified, increasing in the aged electrodes, more dramatically in the Li‐ion system, which explains the poorer cycle life as Li‐ion cathode material. Local spectra, revealing different oxidation states over the sample with strong correlation between the Fe L‐edge, Mn L‐edge, and N K‐edge, imply a coupling between redox centers and an electron delocalization over the host framework.
Toward design a secure protocol for updating remotely stored credentials of a crypto‐biometric framework for multi‐server environment
Authors: Barman Subhas , Chattopadhyay Samiran , Samanta Debasis
Published: August 2023

Integration of biometric data with cryptography is gaining importance to develop a secure distributed communication system. The main issue with this strategy is updating a biometric template and other credentials (like a cryptographic key) and sharing the same in a secure manner. This paper proposes a novel approach to protect a credential under the security of biometric data using fuzzy commitment so that it can be securely stored on a remote server. Furthermore, a protocol has been proposed to update the cryptographic key and biometric data online and share the same among communicating parties through a network channel. A rigorous security analysis of the scheme establishes the robustness of the scheme against many known attacks. In addition to this, to substantiate that the protocol is provably secure, it has been critically verified with two protocol verification tools, namely, the RO (Random Oracle) Model and the AVISPA (automated validation of Internet Security Protocols and Applications) tool. The proposed protocol is useful to design a multiparty system having a multi‐user and multi‐server environment.
Water stress and sustainability challenges: Evidence from sub‐Saharan Africa
Authors: Salman Abdou Doaa M. , Rajab Mohamad Mussad Ibrahim
Published: August 2023

Sub‐Saharan Africa is considered one of the hotspots most likely to be affected by water problems due to the region's heavy reliance on agriculture. This study has three objectives. First, it aims to assess the driving factors that influence environmental performance in Sub‐Saharan countries. Second, it investigates the impact of water scarcity on sustainable development in sub‐Saharan nations by utilizing available data on the environmental performance index (EPI) from 2000 to 2010, which is the only complete and accessible time series. Third, it seeks to identify the effect of carbon dioxide emissions on the EPI. To achieve these objectives, the study employs an empirical dynamic autoregressive distributed lag (ARDL) approach and a panel of selected countries in sub‐Saharan Africa to examine long‐term equilibrium and short‐term adjustments. The results indicate a positive correlation between population growth and EPI in Angola, Cameroon, Ghana, and South Africa. In the long term, the population coefficient exhibits a negative and significant relationship with EPI. Maternal mortality rates were found to have 1% relevance, while health spending was deemed irrelevant. Both carbon emissions and the proportion of the population with improved water sources had a negative and significant impact on the environmental index. The findings underscore the conflicts between water demand and other explanatory variables on water stress in sub‐Saharan countries. Thus, the study recommends the urgent formulation of regional policies to effectively safeguard future generations from the threat of water poverty.
Parareal with a Physics-Informed Neural Network as Coarse Propagator
Authors: Ibrahim Abdul Qadir , Götschel Sebastian , Ruprecht Daniel
Published: August 2023

Parallel-in-time algorithms provide an additional layer of concurrency for the numerical integration of models based on time-dependent differential equations. Methods like Parareal, which parallelize across multiple time steps, rely on a computationally cheap and coarse integrator to propagate information forward in time, while a parallelizable expensive fine propagator provides accuracy. Typically, the coarse method is a numerical integrator using lower resolution, reduced order or a simplified model. Our paper proposes to use a physics-informed neural network (PINN) instead. We demonstrate for the Black-Scholes equation, a partial differential equation from computational finance, that Parareal with a PINN coarse propagator provides better speedup than a numerical coarse propagator. Training and evaluating a neural network are both tasks whose computing patterns are well suited for GPUs. By contrast, mesh-based algorithms with their low computational intensity struggle to perform well. We show that moving the coarse propagator PINN to a GPU while running the numerical fine propagator on the CPU further improves Parareal’s single-node performance. This suggests that integrating machine learning techniques into parallel-in-time integration methods and exploiting their differences in computing patterns might offer a way to better utilize heterogeneous architectures.
Representation Learning and NLP
Authors: Liu Zhiyuan , Sun Maosong
Published: August 2023

Natural language processing (NLP) aims to build linguistic-specific programs for machines to understand and use human languages. Conventional NLP methods heavily rely on feature engineering to constitute semantic representations of text, requiring careful design and considerable expertise. Meanwhile, representation learning aims to automatically build informative representations of raw data for further application and achieves significant success in recent years. This chapter presents a brief introduction to representation learning, including its motivation, history, intellectual origins, and recent advances in both machine learning and NLP.
Biomedical Knowledge Representation Learning
Authors: Zeng Zheni , Liu Zhiyuan , Lin Yankai , Sun Maosong
Published: August 2023

As a subject closely related to our life and understanding of the world, biomedicine keeps drawing much attention from researchers in recent years. To help improve the efficiency of people and accelerate the progress of this subject, AI techniques especially NLP methods are widely adopted in biomedical research. In this chapter, with biomedical knowledge as the core, we launch a discussion on knowledge representation and acquisition as well as biomedical knowledge-guided NLP tasks and explain them in detail with practical scenarios. We also discuss current research progress and several future directions.
Sentence and Document Representation Learning
Authors: Ding Ning , Lin Yankai , Liu Zhiyuan , Sun Maosong
Published: August 2023

Sentence and document are high-level linguistic units of natural languages. Representation learning of sentences and documents remains a core and challenging task because many important applications of natural language processing (NLP) lie in understanding sentences and documents. This chapter first introduces symbolic methods to sentence and document representation learning. Then we extensively introduce neural network-based methods for the far-reaching language modeling task, including feed-forward neural networks, convolutional neural networks, recurrent neural networks, and Transformers. Regarding the characteristics of a document consisting of multiple sentences, we particularly introduce memory-based and hierarchical approaches to document representation learning. Finally, we present representative applications of sentence and document representation, including text classification, sequence labeling, reading comprehension, question answering, information retrieval, and sequence-to-sequence generation.
Knowledge Representation Learning and Knowledge-Guided NLP
Authors: Han Xu , Chen Weize , Liu Zhiyuan , Lin Yankai , Sun Maosong
Published: August 2023

Knowledge is an important characteristic of human intelligence and reflects the complexity of human languages. To this end, many efforts have been devoted to organizing various human knowledge to improve the ability of machines in language understanding, such as world knowledge, linguistic knowledge, commonsense knowledge, and domain knowledge. Starting from this chapter, our view turns to representing rich human knowledge and using knowledge representations to improve NLP models. In this chapter, taking world knowledge as an example, we present a general framework of organizing and utilizing knowledge, including knowledge representation learning, knowledge-guided NLP, and knowledge acquisition. For linguistic knowledge, commonsense knowledge, and domain knowledge, we will introduce them in detail in subsequent chapters considering their unique knowledge properties.
Mechanical Behaviors of Corroded Prestressing Strands
Authors: Wang Lei
Published: August 2023

Corrosion will reduce the cross-sectional area of strands and deteriorate the mechanical property of prestressing strands. In this chapter, nineteen corroded strands are obtained through controlling stress level, corrosion time, and chloride ion concentration under artificial climate conditions. Then, the size and geometry of corrosion pits are measured, and its probability distribution is investigated. Furthermore, static tensile tests are carried out to study the mechanical property of prestressing strands after corrosion. Following this, a constitutive model of corroded prestressing strand is proposed.
Bond Behavior Between Strand and Concrete with Corrosive Cracking
Authors: Wang Lei
Published: August 2023

Bond behavior between strand and concrete plays a decisive role in sustaining the properties of prestressed concrete structures. This chapter mainly discusses the bond behavior between corroded strand and concrete. First, the effects of corrosion-induced crack on the bond between strand and concrete are studied based on the pull-out test; the confinement role of stirrups on the deterioration of bond behavior affected by concrete cracking is addressed. Next, the bond behavior of corroded strand in pretensioned concrete structures is investigated by the bending test; the effects of strand corrosion on force–slip curves, bond strength, and failure mode are discussed.
Large N partition functions of 3d holographic SCFTs
Authors: Bobev Nikolay , Hong Junho , Reys Valentin
Published: August 2023

Abstract

We study the S1 × $$ {\Sigma}_{\mathfrak{g}} $$

Σ
g

topologically twisted index and the squashed sphere partition function of various 3d $$ \mathcal{N} $$
N
≥ 2 holographic superconformal field theories arising from M2-branes. Employing numerical techniques in combination with well-motivated conjectures we provide compact closed-form expressions valid to all orders in the perturbative 1/N expansion for these observables. We also discuss the holographic implications of our results for the topologically twisted index for the dual M-theory Euclidean path integral around asymptotically AdS4 solutions of 11d supergravity. In Lorentzian signature this leads to a prediction for the corrections to the Bekenstein-Hawking entropy of a class of static asymptotically AdS4 BPS black holes.
Canonical purification and the quantum extremal shock
Authors: Parrikar Onkar , Singh Vivek
Published: August 2023

Abstract

We study the canonical purification of pure, bi-partite states (with respect to one of the parties) obtained by turning on sources in the Euclidean path integral. In holographic conformal field theories, the Lorentzian bulk dual of the canonical purification consists of the corresponding entanglement wedge glued to its CRT image at the quantum extremal surface. However, the mismatch in the classical expansions at the QES due to quantum corrections needs to be supported by a shock in the bulk matter stress tensor in order for the bulk to satisfy Einstein’s equations. Working perturbatively to first order in double-trace sources around the thermofield double state, we demonstrate that the state of the bulk matter in the dual to the canonically purified boundary CFT state precisely has this quantum extremal shock in the bulk stress tensor. We interpret our results as the emergence of gravitational physics from the CFT entanglement structure in a context where bulk quantum corrections are important.
Effects of low doses of methylmercury (MeHg) exposure on definitive endoderm cell differentiation in human embryonic stem cells
Authors: Li Bai , Jin Xiaolei , Chan Hing Man
Published: August 2023

Fetal development is one of the most sensitive windows to methylmercury (MeHg) toxicity. Laboratory and epidemiological studies have shown a dose–response relationship between fetal MeHg exposure and neuro performance in different life stages from infants to adults. In addition, MeHg exposure has been reported to be associated with disorders in endoderm-derived organs, such as morphological changes in liver cells and pancreatic cell dysfunctions. However, the mechanisms of the effects of MeHg on non-neuronal organs or systems, especially during the early development of endoderm-derived organs, remain unclear. Here we determined the effects of low concentrations of MeHg exposure during the differentiation of definitive endoderm (DE) cells from human embryonic stem cells (hESCs). hESCs were exposed to MeHg (0, 10, 100, and 200 nM) that covers the range of Hg concentrations typically found in human maternal blood during DE cell induction. Transcriptomic analysis showed that sub-lethal doses of MeHg exposure could alter global gene expression patterns during hESC to DE cell differentiation, leading to increased expression of endodermal genes/proteins and the over-promotion of endodermal fate, mainly through disrupting calcium homeostasis and generating ROS. Bioinformatic analysis results suggested that MeHg exerts its developmental toxicity mainly by disrupting ribosome biogenesis during early cell lineage differentiation. This disruption could lead to aberrant growth or dysfunctions of the developing endoderm-derived organs, and it may be the underlying mechanism for the observed congenital diseases later in life. Based on the results, we proposed an adverse outcome pathway for the effects of MeHg exposure during human embryonic stem cells to definitive endoderm differentiation.
Magnetoelectric properties of multiferroic ceramic composites
Authors: Bochenek Dariusz , Niemiec Przemysław , Chrobak Artur , Guzdek Piotr
Published: August 2023

The paper analyzes the influence of hard and soft admixture on the functional properties of multiferroic ceramic composites. Two composite materials via solid-state reaction route were obtained. PZT-type materials (with hard or soft admixture) were selected as the ferroelectric component (90%), and nickel–zinc ferrite as the magnetic component (10%). The influence of the doping type (soft and hard admixture of the ferroelectric composite component) on multiferroic composites’ dielectric, ferroelectric, electromechanical, magnetic, and magnetoelectric properties were analyzed. Microstructural studies revealed the microstructure of composites with the correct distribution of the magnetic component in the ferroelectric matrix, suitable for maintaining both the ferroelectric and magnetic properties of composite materials. Research has shown that using a ferroelectric component as the PZT (from the morphotropic region and doped with the ferroelectrically soft niobium admixture) shows many advantages, positively influencing the functional properties of the multiferroic composite. It ensures effective polarization of the composite sample, obtaining a high magnetoelectric effect, which is required in sensors or magnetoelectric converters. PZT with a hard admixture shows higher stability of physical parameters, but its characteristic property also hinders the effective polarization of the composite sample.
The impact of colon injuries on the outcome of gunshot wounds to the abdomen
Authors: Singh Yonita , Motilall Sooraj , Khulu Bongani L. , Jackson Brandon S.
Published: August 2023

Purpose

Factors predicting morbidity and mortality in patients with colon-related gunshot injuries and the management of these injuries are not always straightforward. This aimed to assess the impact of abdominal gunshot wounds with colonic injuries on patients’ overall outcomes.

Methods

This cross-sectional prospective observational study compared patients with colon injuries and without colon injuries. Data was collected from admission, theatre and postoperative care. Patients were recruited between 1 January 2020 and 20 October 2021.

Results

Of 132 patients with abdominal gunshot injuries, 71 (54.0%) had colon injuries. The colon injury group had a higher incidence of laparotomy wound sepsis (p<0.0001), bullet exit wound infection (p<0.0001), tract necrotizing fasciitis (p<0.0001), relook laparotomies (p<0.0001) and a longer hospital stay (p<0.0001). Septicaemia (p=0.002) or anastomotic leak (p=0.041) was associated with a penetrating abdominal trauma index (PATI) ≥25. Most patients who developed tract necrotizing fasciitis did not have their tract debrided/ lavaged (p=0.004). The type of colon repair did not influence the length of hospital stay (p=0.688) or the development of a colon-related complication (p=0.578). Between 18 and 25 years (p<0.0001) and >2 organs injured (p=0.018) were associated with colon-related complications. Patients between 18 and 25 years were 4.748 times more likely to develop a colon-related complication (p=0.046).

Conclusion

Gunshot wounds to the abdomen with associated colonic injuries had a worse outcome with an increased risk of developing wound infections. There is no difference in the operative management of colonic injury. Patients between the ages of 18 and 25 years or >2 organs injured are more likely to develop a complication.
Trabecular Bone Score in Assessing Bone Mineralization Status in Children with End- Stage Renal Disease: A Promising Tool
Authors: Salem Nanees , Bakr Ashraf , Eid Riham
Published: August 2023

Areal-bone mineral density (aBMD) of lumbar-spine dual energy X-ray absorptiometry (DXA) scan is the most frequently used tool in evaluating BMD in pediatric patients, however its size dependency have significant impact on measurements accuracy in children with chronic kidney disease (CKD). This study aimed to evaluate the usefulness of trabecular bone score (TBS) computed during lumbar-spine DXA scan in assessing bone status in children on maintenance hemodialysis (HD). Ninety-three children on HD (aged 9–18 years) were subjected to lumbar-spine DXA-scan to obtain aBMD (g/cm2) and TBS.

Z-scores of aBMD for chronological-age (aBMDZ-CA), height-age (aBMDZ-HA), and TBSZ-score were calculated using mean and SD values of 442 healthy controls. aBMD and TBS were significantly lower in short-for-age and normal height-for-age patients compared to the corresponding values of controls (p < 0.05 for all). Degraded vertebral microarchitecture (TBSZ-score < -2) was detected in 48% and 44% of male and female patients respectively. There were no significant differences in median TBSZ-score between short-for-age and normal height-for-age HD patients in male (p = 0.425) and in female (p = 0.316) patients. TBSZ-score correlated significantly with aBMDZ-CA (r = 0.234; p = 0.024) but not with aBMDZ-HA (r = 0.077; p = 0.462). Patients with history of fractures (5 patients only) had significantly lower TBS scores compared to those without fracture history (p = 0.016).

Conclusion: TBS is significantly reduced in children on maintenance HD and is associated with increased fracture incidence. TBS has shown to be a promising tool in assessing bone quality (trabecular microarchitecture) in children with CKD being not size-dependent as is a-BMD, for further evaluation of its potential role in therapeutic and follow-up decisions.

What is Known:• In children with CKD, bone demineralization starts as early as CKD stage 2, so assessment of bone health is mandatory for follow up and therapeutic decisions.• aBMD of lumbar-spine DXA scan is the most used tool in evaluating BMD in pediatric patients, however its size dependency have significant impact on measurements made in children with CKD.

What is New:• TBS is significantly reduced in children on maintenance HD and associated with increased fracture incidence.• TBS has shown to be a promising tool in assessing bone quality (trabecular microarchitecture) in children with CKD being not size-dependent as is a-BMD.
Telestration with augmented reality improves the performance of the first ten ex vivo porcine laparoscopic cholecystectomies: a randomized controlled study
Authors: Cizmic Amila , Müller Felix , Wise Philipp A. , Häberle Frida , Gabel Felix , Kowalewski Karl-Friedrich , Bintintan Vasile , Müller-Stich Beat P. , Nickel Felix
Published: August 2023

Introduction

The learning curve in minimally invasive surgery (MIS) is steep compared to open surgery. One of the reasons is that training in the operating room in MIS is mainly limited to verbal instructions. The iSurgeon telestration device with augmented reality (AR) enables visual instructions, guidance, and feedback during MIS. This study aims to compare the effects of the iSurgeon on the training of novices performing repeated laparoscopic cholecystectomy (LC) on a porcine liver compared to traditional verbal instruction methods.

Methods

Forty medical students were randomized into the iSurgeon and the control group. The iSurgeon group performed 10 LCs receiving interactive visual guidance. The control group performed 10 LCs receiving conventional verbal guidance. The performance assessment using Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores, the total operating time, and complications were compared between the two groups.

Results

The iSurgeon group performed LCs significantly better (global GOALS 17.3 ± 2.6 vs. 16 ± 2.6, p ≤ 0.001, LC specific GOALS 7 ± 2 vs. 5.9 ± 2.1, p ≤ 0.001, global OSATS 25.3 ± 4.3 vs. 23.5 ± 3.9, p ≤ 0.001, LC specific OSATS scores 50.8 ± 11.1 vs. 41.2 ± 9.4, p ≤ 0.001) compared to the control group. The iSurgeon group had significantly fewer intraoperative complications in total (2.7 ± 2.0 vs. 3.6 ± 2.0, p ≤ 0.001) than the control group. There was no difference in operating time (79.6 ± 25.7 vs. 84.5 ± 33.2 min, p = 0.087).

Conclusion

Visual guidance using the telestration device with AR, iSurgeon, improves performance and lowers the complication rates in LCs in novices compared to conventional verbal expert guidance.
Variational sensitivity analysis and shape optimisation applied to a non-local, ductile damage model
Authors: Guhr Fabian , Barthold Franz-Joseph
Published: August 2023

Shape optimisation is applied to an elasto-plastic material model with non-local, regularised damage. Geometries of the same volume are generated which behave better under the aspect of damage accumulation. The underlying material model is taken from published literature and enhanced to derive the sensitivities w.r.t the initial reference geometry. A variational approach, together with an enhanced kinematic concept to decouple geometrical and physical quantities, is utilised to derive these sensitivities. With the inclusion of plastic and damaging effects, the load history of the problem has to be taken into account as well. This introduces additional terms for the sensitivity analysis and requires certain adjustments within the numerical treatment. These gradient information can finally be applied in gradient-based optimisation techniques to efficiently solve the stated optimisation problem. The two discussed examples highlight the benefit of damage optimisation. In the first example, a geometry is reshaped to directly reduce the damage accumulation under certain load. In a second example, the results of a compliance based optimisation with the ductile damage material behaviour are compared to shapes resulting from optimisation problems considering elastic and elasto-plastic material behaviour.
An uncertainty estimator method based on the application of feature density to classify mammograms for breast cancer detection
Authors: Fuentes-Fino Ricardo , Calderón-Ramírez Saúl , Domínguez Enrique , López-Rubio Ezequiel , Elizondo David , Molina-Cabello Miguel A.
Published: August 2023

In the area of medical imaging, one of the factors that can negatively influence the performance of prediction algorithms is the limited number of observations for each class within a labeled dataset. Usually, in order to increase the samples, a second set of unlabeled images is used. However, this set adds two new problems (i) finding patient observations with different pathologies than those observed in the labeled data set and (ii) finding images belonging to a different distribution from the dataset used in the model training process. This way, merging datasets from different sources can have an adverse effect on the distribution of features. Encountering this type of data (better known as out-of-distribution data) within the deployment environments may also lead to varying degrees of performance degradation as can be seen in the different experimental results obtained. In this research, a study of the behavior of Feature Density is made, as a mathematical model for the estimation of predictive uncertainty in supervised classification algorithms, in order to improve the behavior when out-of-distribution data are presented in the dataset. The Feature Density method is based on the estimation of feature density by means of histogram calculation (or Probability Density Function). The advantage of this method over the baseline approach (Mahalanobis distance) is that it does not assume a Gaussian-type distribution of sample characteristics and serves to estimate the uncertainty. This work focuses on the binary classification of mammography X-ray images from three different datasets simulating the condition of a different degree of contamination with out-of-distribution sample. According to the obtained results, the performance of the proposed method depends directly on the architecture of the implemented neural network.
Ultrastructural organization of the thylakoid system during the afternoon relocation of the giant chloroplast in Selaginella martensii Spring (Lycopodiophyta)
Authors: Colpo Andrea , Demaria Sara , Boldrini Paola , Baldisserotto Costanza , Pancaldi Simonetta , Ferroni Lorenzo
Published: August 2023

Within the ancient vascular plant lineage known as lycophytes, many Selaginella species contain only one giant chloroplast in the upper epidermal cells of the leaf. In deep-shade species, such as S. martensii, the chloroplast is cup-shaped and the thylakoid system differentiates into an upper lamellar region and a lower granal region (bizonoplast). In this report, we describe the ultrastructural changes occurring in the giant chloroplast hosted in the epidermal cells of S. martensii during the daily relocation of the organelle. The process occurs in up to ca. 40% of the microphylls without the plants being exposed to high-light flecks. The relocated chloroplast loses its cup shape: first, it flattens laterally toward the radial cell wall and then assumes a more globular shape. The loss of the conical cell shape, the side-by-side lateral positioning of vacuole and chloroplast, and the extensive rearrangement of the thylakoid system to only granal cooperate in limiting light absorption. While the cup-shaped chloroplast emphasizes the light-harvesting capacity in the morning, the relocated chloroplast is suggested to support the renewal of the thylakoid system during the afternoon, including the recovery of photosystem II (PSII) from photoinhibition. The giant chloroplast repositioning is part of a complex reversible reshaping of the whole epidermal cell.
In paired preference tests, domestic chicks innately choose the colour green over red, and the shape of a frog over a sphere when both stimuli are green
Authors: Protti-Sánchez Francesca , Mayer Uwe , Rowland Hannah M.
Published: August 2023

Many animals express unlearned colour preferences that depend on the context in which signals are encountered. These colour biases may have evolved in response to the signalling system to which they relate. For example, many aposematic animals advertise their unprofitability with red warning signals. Predators’ innate biases against these warning colours have been suggested as one of the potential explanations for the initial evolution of aposematism. It is unclear, however, whether unlearned colour preferences reported in a number of species is truly an innate behaviour or whether it is based on prior experience. We tested the spontaneous colour and shape preferences of dark-hatched, unfed, and visually naive domestic chicks (Gallus gallus). In four experiments, we presented chicks with a choice between either red (a colour typically associated with warning patterns) or green (a colour associated with palatable cryptic prey), volume-matched spheres (representing a generalised fruit shape) or frogs (representing an aposematic animal’s shape). Chicks innately preferred green stimuli and avoided red. Chicks also preferred the shape of a frog over a sphere when both stimuli were green. However, no preference for frogs over spheres was present when stimuli were red. Male chicks that experienced a bitter taste of quinine immediately before the preference test showed a higher preference for green frog-shaped stimuli. Our results suggest that newly hatched chicks innately integrate colour and shape cues during decision making, and that this can be augmented by other sensory experiences. Innate and experience-based behaviour could confer a fitness advantage to novel aposematic prey, and favour the initial evolution of conspicuous colouration.
Migration-related inequalities in loneliness across age groups: a cross-national comparative study in Europe
Authors: Delaruelle Katrijn
Published: August 2023

This study aims to contribute to the growing interest in the consequences of migration for loneliness by investigating the role of generational status across various age groups in countries with differing integration policies and attitudes towards immigrants. Using data from rounds 5, 6 and 7 of the European Social Survey, I conducted logistic multilevel models on a sample of 121,835 respondents aged 18 years and older, residing in 26 countries. Loneliness was assessed based on a single-item item question from the Center for Epidemiologic Studies of Depression scale. The findings suggest that individuals with a migration background are more likely to experience loneliness than those without. Within this group, I found that first-generation immigrants who arrived after the age of 18 are more vulnerable to loneliness than those who arrived earlier, although the latter still reported more loneliness than second-generation immigrants. Furthermore, migration-related inequalities in loneliness were greater among the youngest age group (18–34 years) and in countries with a more positive public stance towards immigrants. In sum, this study highlights the persistent challenges that migration poses for loneliness across generations and age groups, and emphasizes the need to extend research in this area beyond older adults. Moreover, it suggests that promoting a welcoming culture towards immigrants may have unintended consequences for loneliness gaps, but further research is needed to explain this observation.
Patterns of cytonuclear discordance and divergence between subspecies of the scarlet macaw (Ara macao) in Central America
Authors: Aardema Matthew L. , Schmidt Kari L. , Amato George
Published: August 2023

The scarlet macaw, Ara macao, is a neotropical parrot that contains two described subspecies with broadly discrete geographical distributions. One subspecies, A. m. macao, is found from South America north into southwestern Costa Rica, while the second subspecies, A. m. cyanoptera, is found from eastern Costa Rica north into central Mexico. Our previous research using mitochondrial data to examine phylogeographical divergence across the collective range of these two subspecies concluded that they represent distinct evolutionary entities, with minimal contemporary hybridization between them. Here we further examine phylogenetic relationships and patterns of genetic variation between these two subspecies using a dataset of genetic markers derived from their nuclear genomes. Our analyses show clear nuclear divergence between A. m. macao and A. m. cyanoptera in Central America. Collectively however, samples from this region appear genetically more similar to one another than they do to the examined South American (Brazilian) A. m. macao sample. This observation contradicts our previous assessments based on mitochondrial DNA analyses that A. m. macao in Central and South America represent a single phylogeographical group that is evolutionarily distinct from Central American A. m. cyanoptera. Nonetheless, in agreement with our previous findings, ongoing genetic exchange between the two subspecies appears limited. Rather, our analyses indicate that incomplete lineage sorting is the best supported explanation for cytonuclear discordance within these parrots. High-altitude regions in Central America may act as a reproductive barrier, limiting contemporary hybridization between A. m. macao and A. m. cyanoptera. The phylogeographic complexities of scarlet macaw taxa in this region highlight the need for additional evolutionary examinations of these populations.
Occupational aspirations at the end of compulsory schooling: The interplay of parents’ educational background, work values and self-Concepts in the reproduction of inequality
Authors: Astleithner Franz , Vogl Susanne , Kogler Raphaela
Published: August 2023

Decisions about further schooling or vocational training are imminent at the end of lower secondary education, and they determine educational and occupational trajectories. Understanding decision processes during this transition helps to elucidate the intergenerational reproduction of inequality. The aim of this study is to untangle influences on students’ occupational aspirations and how their parents’ educational level shapes these aspirations. We analysed data from an online survey of 3078 students at approximately 15 years of age in the general track of lower secondary school (‘Neue Mittelschule’) in Vienna (Austria). Based on regression analyses and path models, we show that educational background is related to occupational aspirations. Work values, attitudes towards school and social capital shape occupational aspirations but cannot be (fully) explained by educational background. Furthermore, we find no evidence that locus of control affects the level of occupational aspirations.
Leisure time in young people’s everyday life and its relevance for wellbeing: longitudinal analyses based on a quantitative panel in Vienna
Authors: Mataloni Barbara
Published: August 2023

Qualitative studies with young people have shown that wellbeing is something that is felt and sensed in their everyday lives, especially in less formal leisure-time contexts. This article contributes to the current state of research by analyzing the relations between wellbeing and the conditions in young people’s leisure time using a longitudinal, quantitative approach. The analyses are based on a new measurement instrument, which captures conditions in young people’s leisure time in terms of the extent to which they facilitate correspondence and experimentation, and require adaption. The measurement instrument was inserted twice (2020, 2022) in the quantitative panel of ‘Pathways to the Future’, a project about young people in Vienna. The analytical sample consists of 239 panel participants (478 observations), and the main results are based on the specification of a random effects model. The findings reveal that possibilities for correspondence in the panel participants’ leisure time, i.e., being able to be oneself and to relax, increase their wellbeing. In addition, to a lesser extent, possibilities for experimentation, i.e., discovering new traits about oneself and engaging in stimulating activities, are important for wellbeing. Interestingly, leisure time requiring adaption is not significantly related to wellbeing. More detailed analyses considering decreases and increases of adaption separately by estimating asymmetric effects suggest that adaption can be constraining but can also be more positively connotated. Overall, the results contribute to a relational and situational understanding of wellbeing in quantitative research, which places the focus on the conditions in young people’s everyday life.
A Delphi consensus on the management of Spanish patients with osteoporosis at high risk of fracture: OSARIDELPHI study
Authors: Arboleya Luis , Cancio-Trujillo Jose Manuel , Chaves Celia , Duaso-Magaña Enric , Mesa-Ramos Manuel , Olmos Jose Manuel
Published: August 2023

The OSARIDELPHI study evaluated the level of agreement between specialists in osteoporosis regarding the management of patients with high-risk fractures in Spain. The results provide expert-based recommendations for prevention, diagnosis, and treatment related to fracture risk. Therefore, the study facilitates clinical decision-making for managing this patient’s profile.

Purpose

To evaluate the level of agreement between specialists in osteoporosis regarding the management of patients with high-risk fractures in Spain.

Methods

A two-round Delphi study was performed using an online survey. In round 1, panel members rated their level of agreement with assessments on a 9-point Likert scale. Item selection was based on acceptance by ≥ 66.6% of panel experts and the agreement of the scientific committee. In round 2, the same panelists evaluated non-consensus items in round 1.

Results

A total of 80 panelists participated in round 1; of these, 78 completed the round 2 survey. In round 1, 122 items from 4 dimensions (definition of fracture risk: 11 items, prevention and diagnosis: 38 items, choice of treatment: 24 items, and treatment-associated quality of life: 49 items) were evaluated. The consensus was reached for 90 items (73.8%). Panelists agreed that categorizing high risk, very high risk, or imminent risk determines secondary prevention actions (97.5%). Experts agreed that treatment with bone-forming drugs should be considered in case of a very high risk of fracture, and a sequential change to antiresorptive drugs should be made after 1–2 years (97.5%). Panelists also recommended corrective action plans for non-adherent patients to improve adherence (97.5%). A total of 131 items were finally accepted after round 2.

Conclusion

This Delphi study provides expert-based recommendations on clinical decision-making for managing patients with osteoporosis at high risk of fracture.
CircRNA-CIRH1A Promotes the Development of Osteosarcoma by Regulating PI3K/AKT and JAK2/STAT3 Signaling Pathways
Authors: Zhang Meng , Wang Xiang , Zhao Jianfeng , Yan Jizhou , He Xiaodan , Qin Danxia , Liang Fang , Tong Kai , Wang Jianjian
Published: August 2023

Osteogenic sarcoma (OS), one of the mesenchymal tumors with a high degree of malignancy, mainly occurs in the metaphysis of the long bones and around the knee joints in children and adolescents. The poor diagnosis in patients with OS can be attributed to the lack of early clinical symptoms, although the growth of tumor mass gradually results in severe pain and systemic symptoms. The mechanisms underlying the pathogenesis of OS are not fully understood. Thus, identifying early diagnostic biomarkers and novel targets involved in the progression of OS is of critical significance in the management of OS. CircRNA is a class of non-coding RNAs characterized by the close-loop structure and increased stability, which are implicated in the regulation of cell proliferation, differentiation, migration, and apoptosis. Moreover, circRNAs also play significant roles in aging and chronic disorders, such as cancer and cardiovascular diseases. Accordingly, we reported the upregulation of circRNA-CIRH1A in OS tissues and cell lines. Silencing circRNA-CIRH1A in OS cell lines (U2OS, HOS, Saos-2, and MG-63) could inhibit the cell proliferation, invasion, migration, and apoptosis, which was also validated in xenograft tumorigenesis mouse model. We further demonstrated that circRNA-CIRH1A sponged miR-1276, which subsequently disrupted the effect of miR-1276 on PI3K/AKT and JAK2/STAT3 signaling pathways. Together, our study revealed the oncogenic role of circRNA-CIRH1A in OS, and identified miR-1276/ PI3K-AKT and JAK2-STAT3 signaling axis as the key downstream mediators of circRNA-CIRH1A.
Generalized partially bent functions, generalized perfect arrays, and cocyclic Butson matrices
Authors: Armario J. A. , Egan R. , Flannery D. L.
Published: August 2023

In a recent survey, Schmidt compiled equivalences between generalized bent functions, group invariant Butson Hadamard matrices, and abelian splitting relative difference sets. We establish a broader network of equivalences by considering Butson matrices that are cocyclic rather than strictly group invariant. This result has several applications; for example, to the construction of Boolean functions whose expansions are generalized partially bent functions, including cases where no bent function can exist.
New developments in radiation oncology for head and neck cancers
Authors: Resl Christoph , Georg Petra , Döller Carmen
Published: August 2023

Treatment of head and neck cancers is multidisciplinary involving surgery, radiotherapy and systemic treatment. The disease outcome depends on multiple factors involving tumour biology and behaviour as well patient’s clinical condition and comorbidities. Taking into account all these factors, the treatment decision should be tailored according to tumour characteristics and patient’s needs. Treatment could be de-intensified on the one hand, or intensified on the other hand, with the aim to achieve the best therapeutic outcome. New developments in radiation oncology shift the focus toward personalised patient treatment including clinical information, multimodality imaging and early assessments of treatment response to adapt the treatment.