bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature‐dependent inter‐laminar fracture behavior of waste short carbon fiber embedded glass fiber/epoxy composites
Authors: Dasari Srinivasu , Patnaik Satyaroop , Prusty Rajesh Kumar
Published: July 2023

Delamination is one of the life‐limiting failure modes for fiber reinforced polymer (FRP) composite composites resulting in poor damage tolerance, as this failure mode occurs at considerably lower loads. Owing to the enormous demand and mass production of FRP composites, a large amount of fiber waste is produced worldwide. This triggers concern about utilizing these fiber wastes for some valuable applications. The present study aims to improve the overall damage tolerance of laminated glass/epoxy composites via the introduction of waste short carbon fibers (SCFs) reinforcement in the epoxy matrix. The effect of various SCF contents (0.1, 0.3, and 0.5 wt%) in glass fiber/epoxy composites were evaluated experimentally for their interlaminar fracture toughness in terms of both crack development and propagation under mode I and II interlaminar fracture toughness tests, at elevated temperatures (30, 50, and 70°C). Based on the experimental results, glass/epoxy composite with 0.1 wt% of SCF revealed 13.49% and 20.45% increment in mode I and II interlaminar fracture toughness, respectively, at ambient temperature. A positive reinforcement effect could be noticed for GIC and GIIC values up to 50°C. However, due to residual interfacial stresses, interfacial debonding, and epoxy softening, a negative reinforcement effect could be noticed at 70°C. Delamination initiation and crack propagation mechanisms have been explored at elevated temperatures. Fractographic studies have been carried out using a scanning electron microscope to identify the failure mechanisms.
The role of leucine and isoleucine in tuning the hydropathy of class A GPCRs
Authors: Baumann Christian , Zerbe Oliver
Published: July 2023

Leucine and Isoleucine are two amino acids that differ only by the positioning of one methyl group. This small difference can have important consequences in α‐helices, as the β‐branching of Ile results in helix destabilization. We set out to investigate whether there are general trends for the occurrences of Leu and Ile residues in the structures and sequences of class A GPCRs (G protein‐coupled receptors). GPCRs are integral membrane proteins in which α‐helices span the plasma membrane seven times and which play a crucial role in signal transmission. We found that Leu side chains are generally more exposed at the protein surface than Ile side chains. We explored whether this difference might be attributed to different functions of the two amino acids and tested if Leu tunes the hydrophobicity of the transmembrane domain based on the Wimley‐White whole‐residue hydrophobicity scales. Leu content decreases the variation in hydropathy between receptors and correlates with the non‐Leu receptor hydropathy. Both measures indicate that hydropathy is tuned by Leu. To test this idea further, we generated protein sequences with random amino acid compositions using a simple numerical model, in which hydropathy was tuned by adjusting the number of Leu residues. The model was able to replicate the observations made with class A GPCR sequences. We speculate that the hydropathy of transmembrane domains of class A GPCRs is tuned by Leu (and to some lesser degree by Lys and Val) to facilitate correct insertion into membranes and/or to stably anchor the receptors within membranes.
Evaluating the CoMorph‐A parametrization using idealized simulations of the two‐way coupling between convection and large‐scale dynamics
Authors: Daleu Chimene L. , Plant Robert S. , Stirling Alison J. , Whitall Mike
Published: July 2023

We present a new methodology to test the interactions of convection schemes with their larger scale environment. A single‐column model (SCM) using the new Met Office convection scheme, CoMorph‐A, and the new Met Office–Natural Environment Research Council cloud‐resolving model (CRM) are coupled to damped‐gravity‐wave‐derived large‐scale dynamics. The coupled models are used to investigate convective responses to stimulus forcings under the influence of interactive large‐scale dynamics. Within CoMorph‐A, the default entrainment varies with the prediction of convection size that is dependent on earlier rainfall, and the sensitivity of the SCM results to the entrainment formulation is explored. We demonstrate that the behaviour of the SCM using CoMorph‐A is now very similar to that of the CRM. For temperature or moisture stimulus applied separately, the SCM adjusts to a new equilibrium that is similar to that in the CRM, but its transient convective responses to stimuli acting to suppress convection are markedly too fast. For a combination of stimuli acting to enhance convection, the SCM responses are stronger than in the CRM. Finally, convective rainfall in the SCM is relatively insensitive to a combination of stimuli acting to enhance and suppress convection simultaneously, in agreement with the CRM. However, the SCM recovery from a non‐precipitating state is overly delayed for the default entrainment formulation but is too rapid when the entrainment rate is fixed at a low rate to represent only the deep convective state. We examined the responses to moisture stimuli of different strengths. Both models produce a monotonic increase of precipitation with column relative humidity (CRH) as well as the sharp increase of precipitation as CRH exceeds a threshold, as seen in observations. Though both models correctly capture the observed CRH threshold, differences from the observed precipitation–CRH relationship are noted. For instance, above the threshold the increase of precipitation with CRH is more abrupt in the SCM than in the CRM and observations. A similar behaviour is obtained in the SCM using low entrainment rate.
The natural domain and its social representation in the community resilience concept
Authors: Stotten Rike
Published: July 2023

Mountain communities in Alpine areas are prone to natural hazard events and sensitive to climate change. In these areas, where communities are complex human‐environmental entanglements, strong community resilience is essential. Community resilience is shaped by a set of interacting domains that provide insights into a community's resilience level and highlights the proactive human agency the domains contain. The relevance of human agency for the natural, economic, social, cultural, and political domains has not yet been revealed. This study explores the interdependencies of the community resilience domains, particularly the natural domain, through the lens of social representation theory. Qualitative data from two remote mountain villages in the Upper Ötztal Valley in Tyrol, Austria, were analyzed. The research reveals that the natural domain is shaped through its social representation. Understanding this social representation contributes to a broader understanding of community resilience and can empower communities to harness the capacities that enhance it.
Synthesis of Microparticles with Diverse Thermally Responsive Shapes Originated from the Same Janus Liquid Crystalline Microdroplets
Authors: Liu Mingzhu , Fu Jiemin , Yang Shu
Published: July 2023

Liquid crystalline elastomer (LCE)‐based microparticles that can change shapes in response to external stimuli are of great interest for potential applications such as artificial cells, micro‐actuators, micro‐valves, and smart drug carriers. Here, the synthesis of LCE microparticles with diverse temperature‐dependent anisotropic shapes originated from the same Janus microdroplets is reported. The Janus microdroplets, suspended in an aqueous solution of surfactants, are transformed from microdroplets consisting of a mixture of liquid crystal (LC) monomers, oligomers, silicone oil, and an organic solvent, after the removal of the organic solvent. The molecular alignment of the LC part at the interface, whether planar, homeotropic, or hybrid, is dependent on the choice of the surfactants but not affected by the silicone oil. After polymerization and solvent extraction of the unreacted components, LCE microparticles of various shapes are obtained depending on the concentration and composition of the surfactants, the weight ratio of the LC part to the silicone oil part, and the choice of the extraction solvent. The microparticles that undergo different synthetic pathways show distinct thermally responsive shapes, much like how stem cells differentiate in different environmental conditions.
Translocation of Proteins through Solid‐State Nanopores Using DNA Polyhedral Carriers
Authors: Yang Jing , Wang Juan , Liu Xuan , Chen Yiming , Liang Yuan , Wang Qi , Jiang Shuoxing , Zhang Cheng
Published: July 2023

The detection of biomolecules at the single molecule level has important applications in the fields of biosensing and biomedical diagnosis. The solid‐state nanopore (SS nanopore) is a sensitive tool for detecting single molecules because of its unique label‐free and low sample consumption properties. SS nanopore translocation of small biomolecules is typically driven by an electronic field force and is thus influenced by the charge, shape, and size of the target molecules. Therefore, it remains challenging to control the translocation of biomolecules through SS nanopores, particularly for different proteins with complex conformations and unique charges. Toward this problem, a DNA polyhedral carrier coating strategy to assist protein translocation through SS nanopores is developed, which facilitates target protein detection. The current signal‐to‐noise ratios are improved significantly using this DNA carrier loading strategy. The proposed method should aid the detection of proteins, which are difficult to translocate through nanopores. This coating‐assisted method offers a wide range of applications for SS nanopore detection and promotes the development of single‐molecule detection.
Controllable Black‐to‐Yellow Phase Transition by Tuning the Lattice Symmetry in Perovskite Quantum Dots
Authors: Li Yuhao , Qin Minchao , Wang Yunfan , Li Shiang , Qin Zhaotong , Tsang Sai‐Wing , Su Chun‐Jen , Ke Yubin , Lu Xinhui
Published: July 2023

The black‐to‐yellow phase transition in perovskite quantum dots (QDs) is more complex than in bulk perovskites, regarding the role of surface energy. Here, with the assistance of in situ grazing‐incidence wide‐angle and small‐angle X‐ray scattering (GIWAXS/GISAXS), distinct phase behaviors of cesium lead iodide (CsPbI3) QD films under two different temperature profiles–instant heating‐up (IHU) and slow heating‐up (SHU) is investigated. The IHU process can cause the phase transition from black phase to yellow phase, while under the SHU process, the majority remains in black phase. Detailed studies and structural refinement analysis reveal that the phase transition is triggered by the removal of surface ligands, which switches the energy landscape. The lattice symmetry determines the transition rate and the coexistence black‐to‐yellow phase ratio. The SHU process allows longer relaxation time for a more ordered QD packing, which helps sustain the lattice symmetry and stabilizes the black phase. Therefore, one can use the lattice symmetry as a general index to monitor the CsPbI3 QD phase transition and finetune the coexistence black‐to‐yellow phase ratio for niche applications.
Carbon Nanosheets‐Based Supercapacitor Materials: Recent Advances and Prospects
Authors: Akib Hasan Md. , Sayantha Aniv Suhrid , Mominul Islam Md.
Published: July 2023

The need for inexpensive and ecologically sustainable energy storage technologies is rising rapidly along with the severity of the world's environmental challenges as well as with the rising demand for portable electronics and hybrid vehicles. Supercapacitors have drawn a lot of attentions lately in this regard because of their ultrahigh power density, outstanding electrochemical stability, and environmental friendliness. Due to various advantages, carbon materials are the choice of designer for developing commercial electrodes for various applications including devising supercapacitors. Two‐dimensional (2D) carbon nanosheets (CNSs) with a large surface area and excellent electronic transport properties have fired up the interest of researchers due to their unique properties and potential applications in energy storage. Such engineered 2D porous CNS may significantly improve the energy storage performance of supercapacitor by enabling fast ion transport and charge transfer kinetics. This article summarizes the most recent and significant advances in the area of activated, porous, graphene‐based various CNSs and their composites with a special focus on their use as supercapacitor electrodes. A succinct overview about their syntheses and key characterizations regarding their different structural aspects have been discussed. The present challenges and prospects in using CNS in supercapacitor applications are highlighted.
Photothermal Conversion of Hydrogel‐Based Biomaterial
Authors: He Tingxiang , Lv Shenghua , Wei Dequan , Feng Rui , Yang Juhui , Yan Yihan , Liu Leipeng , Wu Lei
Published: July 2023

Traditional energy from fossil fuels like petroleum and coal is limited and contributes to global environmental pollution and climate change. Developing sustainable and eco‐friendly energy is crucial for addressing significant challenges such as climate change, energy dilemma and achieving the long‐term development of human society. Biomass hydrogels, which are easily synthesized and modified, have diverse sources and can be designed for different applications. They are being extensively researched for their applications in artificial intelligence, flexible sensing, biomedicine, and food packaging. The article summarizes recent advances in the preparation and applications of biomass‐based photothermal conversion hydrogels, discussing the light source, photothermal agents, matrix, and preparation methods in detail. It also explores the use of these hydrogels in seawater desalination, photothermal therapy, antibacterial agents, and light‐activated materials, offering new ideas for developing sustainable, efficient, and advanced photothermal conversion biomass hydrogel materials. The article concludes with suggestions for future research, highlighting the challenges and prospects in this field and paving the way for developing of long‐lasting, efficient energy materials.
Cisplatin triggers oxidative stress, apoptosis and pro‐inflammatory responses by inhibiting the SIRT1‐mediated Nrf2 pathway in chondrocytes
Authors: Hsieh Pei‐Ling , Tsai Kun‐Ling , Chou Wan‐Ching , Wu Chin‐Hsien , Jou I‐Ming , Tu Yuan‐Kun , Ma Ching‐Hou
Published: July 2023

Although the height of the proliferating layer that was suppressed in the growth plate has been recognized as an adverse effect of cisplatin in pediatric cancer survivors, the detailed pathological mechanism has not been elucidated. Sirtuin‐1 (SIRT1) has been reported as an essential modulator of cartilage homeostasis, but its role in cisplatin‐induced damage of chondrocytes remains unclear. In this study, we examined how cisplatin affected the expression of SIRT1 and cell viability. Next, we showed downregulation of SIRT1 after cisplatin treatment resulted in suppression of Peroxisome proliferator‐activated receptor‐gamma coactivator (PGC‐1α), leading to inhibition of Nrf2 nuclear translocation and subsequently decreased Heme oxygenase‐1(HO‐1) and NAD(P)H Quinone Dehydrogenase 1(NQO‐1) expression. Blockage of the SIRT1/ PGC‐1α axis not only increased oxidative stress with lower antioxidant SOD and GSH, but also contributed to mitochondrial dysfunction evidenced by the collapse of membrane potential and repression of mitochondrial DNA copy number and ATP. We also found that Cisplatin up‐regulated the p38 phosphorylation, pro‐inflammatory events and matrix metalloproteinases (MMPs) in chondrocytes through the SIRT1‐modulated antioxidant manner. Collectively, our findings suggest that preservation of SIRT1 in chondrocytes may be a potential target to ameliorate growth plate dysfunction for cisplatin‐receiving pediatric cancer survivors.
Meaningful benefit and minimal clinically important difference (MCID) in Alzheimer's disease: Open peer commentary
Authors: Cummings Jeffrey
Published: July 2023

Introduction

Approval of the anti‐amyloid monoclonal antibodies has stimulated an important discussion of the value to be placed on the magnitude of slowing achieved by treatment compared to placebo.

Methods

The minimal clinically important difference (MCID) was reviewed in the context of other measures and analyses that provide perspective on the meaningfulness of treatment responses.

Results

TheMCID is a clinician‐anchored approach to making this determination. The MCID applies best to symptomatic therapies for which the drug–placebo difference remains constant. Disease‐modifying therapies produce a progressive divergence of drug and placebo trajectories; early in the course the MCID would not be achieved, later the MCID will be achieved, and with continuing therapy the MCID will be exceeded. Clinicians are not the only stakeholders involved in determining the value proposition of slowing disease progression. Patient‐reported outcomes and caregiver‐related measures offer important complementary insights. Analytic approaches also widen the perspective on the observed drug–placebo differences. Risk ratios, numbers needed to treat versus number needed to harm, time‐to‐event analyses, and predictive benefits based on biomarkers all add depth to the discussion.

Discussion

Multiple stakeholder perspectives are needed to determine the importance to be attributed to the therapeutic changes observed with monoclonal antibody therapies and other emerging treatments.
Effect of biosecurity‐based interventions on broiler crude mortality rate at an early stage of production in the small‐scale farming system in Bangladesh
Authors: Faroque Md Omar , Prank Md Rasel , Ahaduzzaman Md
Published: July 2023

Background

Biosecurity‐based interventions are important health strategies for the control of infectious disease and improve productivity in broiler. There are various reasons why broilers die at the early stages of production; however, biosecurity measures are crucial in reducing the risk of disease prevalence and can therefore affect the overall deaths in a flock for a specific period (crude mortality rate [CMR]).

Objectives

This study was designed to determine the current biosecurity situation on small‐scale broiler farms in Bangladesh and its relationship to the CMR during the early stages of production.

Methods

A cross‐sectional observational study was conducted on small‐scale broiler farms (N = 57) located in peri‐urban areas of Chattogram and Pabna districts of Bangladesh. Descriptive and predictive statistical analyses were performed to estimate the frequency of categorical variables and their effect on CMR.

Results

The findings indicated that around 80% of small‐scale broiler farms lacked adequate biosecurity measures. Both on day 1 (p = 0.012) and on days 2–14 (p = 0.003), flocks with inadequate biosecurity had considerably higher median CMRs. Farms that were near the neighbourhood used wood shavings as bedding, offered tube well/shallow well or supply line water, maintained a brief empty period (≤5 days) before introducing new flocks and began using antibiotics on day 1 all had significantly higher CMR at both days 1 and 2–14.

Conclusions

The findings point to the necessity of implementing stringent biosecurity measures in broiler production in locations where there is a shortage, which can lower the burden of arbitrary antibiotic usage and will lower total production costs due to crude mortality and management‐related issues.
A white paper on good research practices in benchmarking: The case of cluster analysis
Authors: Van Mechelen Iven , Boulesteix Anne‐Laure , Dangl Rainer , Dean Nema , Hennig Christian , Leisch Friedrich , Steinley Douglas , Warrens Matthijs J.
Published: July 2023

To achieve scientific progress in terms of building a cumulative body of knowledge, careful attention to benchmarking is of the utmost importance, requiring that proposals of new methods are extensively and carefully compared with their best predecessors, and existing methods subjected to neutral comparison studies. Answers to benchmarking questions should be evidence‐based, with the relevant evidence being collected through well‐thought‐out procedures, in reproducible and replicable ways. In the present paper, we review good research practices in benchmarking from the perspective of the area of cluster analysis. Discussion is given to the theoretical, conceptual underpinnings of benchmarking based on simulated and empirical data in this context. Subsequently, the practicalities of how to address benchmarking questions in clustering are dealt with, and foundational recommendations are made based on existing literature.

This article is categorized under:

Fundamental Concepts of Data and Knowledge > Data Concepts

Fundamental Concepts of Data and Knowledge > Key Design Issues in Data Mining

Technologies > Structure Discovery and Clustering
Basic sets for some basic functional equations
Authors: Ger Roman
Published: July 2023

Motivated by the well known fact that any nonzero solution of the fundamental Cauchy functional equation may arbitrarily be prescribed on a Hamel basis, we deal with the following problem: given a functional equation $$\begin{aligned} E_1(\varphi ) = E_2(\varphi ) \end{aligned}$$

E
1

(
φ
)

=

E
2

(
φ
)

with the unknown function $$\varphi : X \longrightarrow Y$$

φ
:
X
⟶
Y

, what must the set $$\emptyset \ne Z \subset X$$

∅
≠
Z
⊂
X

be like in order to ensure that an arbitrary function $$\varphi _0: Z \longrightarrow Y$$

φ
0

:
Z
⟶
Y

admits a unique function $$\varphi : X \longrightarrow Y$$

φ
:
X
⟶
Y

solving equation ($$*$$

∗

) and such that $$\varphi _{|_Z} = \varphi _0$$

φ

|

Z

=

φ
0

; if such a set does exist it is termed to be a basic set. We discuss the problem of existence of basic sets for exponential functions, d’Alembert’s functions, sine functions, Cuculière’s functions and hyperbolic tangent type functions, among others.
Phase Retrieval for Nilpotent Groups
Authors: Führ Hartmut , Oussa Vignon
Published: July 2023

We study the phase retrieval property for orbits of general irreducible representations of nilpotent groups, for the classes of simply connected Lie groups, and for finite groups. We prove by induction that in the Lie group case, all irreducible representations do phase retrieval. For the finite group case, we mostly focus on p-groups. Here our main result states that every irreducible representation of an arbitrary p-group with exponent p and size $$\le p^{2+p/2}$$

≤

p

2
+
p
/
2

does phase retrieval. Despite the fundamental differences between the two settings, our inductive proof methods are very similar.
Roboterassistierte viszeralchirurgische Eingriffe in Deutschland
Authors: Brunner Maximilian , ElGendy Amr , Denz Axel , Weber Georg , Grützmann Robert , Krautz Christian
Published: July 2023

Roboterassistenzsysteme werden in der Viszeralchirurgie seit einigen Jahren zunehmend häufiger eingesetzt. Entsprechend ist auch die Zahl der in Deutschland installierten Systeme rapide gestiegen. Wurden 2018 rund 100 Roboterassistenzsysteme in deutschen Kliniken genutzt, waren es 2022 bereits mehr als 200. Ziel dieser Arbeit war es, den aktuellen Entwicklungsstand und Trends der viszeralchirurgischen Roboterchirurgie in Deutschland darzustellen. Hierzu wurden Daten des StuDoQ|Robotik-Registers analysiert. Des Weiteren erfolgte eine deskriptive Analyse konkomitierender DRG-Daten über das Bundesstatistikamt (Destatis), um die Repräsentativität der StuDoQ|Robotik-Registerdaten besser abschätzen zu können. In beiden Datensätzen nahm die jährliche Zahl an roboterassistierten viszeralchirurgischen Eingriffen in Deutschland stetig zu. Im Vergleich zur DRG-Statistik waren im StuDoQ|Robotik-Register je nach Eingriffsart nur 3,7 % bis maximal 36,7 % aller durchgeführten roboterassistierten Eingriffe dokumentiert. Kolorektale Resektionen waren die häufigsten roboterassistierten Eingriffe (StuDoQ: 32,5 % und 36,7 % vs. DRG-Statistik: 24,2 % und 29,7 %) und wiesen beispielsweise niedrige Mortalitätsraten (StuDoQ: 1 % und 1 % vs. DRG-Statistik: 2,3 % und 1,3 %) auf. Aufgrund der niedrigen Erfassungsquoten roboterassistierter Ösophagus‑, Magen‑, Pankreas- und Lebereingriffe konnten für diese Bereiche keine validen Aussagen aus den StuDoQ-Daten abgeleitet werden. Mit den aktuellen Erfassungsquoten ist die Aussagekraft des StuDoQ|Robotik-Registers für einige Eingriffsarten erheblich einschränkt. In Zukunft sollten daher Wege bzw. Maßnahmen eruiert werden, die zu einer deutlichen Erhöhung der Erfassungsquoten führen.
Inferring material properties from FRP processes via sim-to-real learning
Authors: Stieber Simon , Schröter Niklas , Fauster Ewald , Bender Marcel , Schiendorfer Alexander , Reif Wolfgang
Published: July 2023

Fiber reinforced polymers (FRP) provide favorable properties such as weight-specific strength and stiffness that are central for certain industries, such as aerospace or automotive manufacturing. Liquid composite molding (LCM) is a family of often employed, inexpensive, out-of-autoclave manufacturing techniques. Among them, resin transfer molding (RTM), offers a high degree of automation. Herein, textile preforms are saturated by a fluid polymer matrix in a closed mold.Both impregnation quality and level of fiber volume content are of crucial importance for the final part quality. We propose to simultaneously learn three major textile properties (fiber volume content and permeability in X and Y direction) presented as a three-dimensional map based on a sequence of camera images acquired in flow experiments and compare CNNs, ConvLSTMs, and Transformers. Moreover, we show how simulation-to-real transfer learning can improve a digital twin in FRP manufacturing, compared to simulation-only models and models based on sparse real data. The overall best metrics are: IOU 0.5031 and Accuracy 95.929 %, obtained by pretrained transformer models.
High revision rates and mortality after distal femoral replacement for periprosthetic distal femoral fractures: analysis from the German Arthroplasty Registry (EPRD)
Authors: Lützner Jörg , Melsheimer Oliver , Steinbrück Arnd , Postler Anne Elisabeth
Published: July 2023

Purpose

This study was initiated to analyze the outcome after distal femoral replacement (DFR) for periprosthetic distal femoral fractures (PDFF).

Methods

Data from the German Arthroplasty Registry (EPRD) were analyzed. A total of 626 patients could be identified with a DFR for PDFF. Mean age was 78.8 years, and 84.2% were female. Revisions and mortality were analyzed and compared with patient groups with a similar procedure (revision total knee arthroplasty) or similar general condition (fracture total hip arthroplasty, hip hemiarthroplasty). Matched-pair-analyses were performed.

Results

Within one year after surgery, 13.2% of the patients had died and further 9.4% were revised. Within four years, 32.7% had died and 19.7% were revised. Revisions were nearly twice as high as in the comparison groups. Periprosthetic infection (PJI) was the most frequent cause for revision, resulting in a PJI rate of 12.8%, which was lower in the comparison groups. Mortality after DFR was as similar high as after fracture hip arthroplasty.

Conclusion

PDFF are a serious injury, and the necessary surgical treatment has a high risk of complications. Every third patient after DFR for PDFF had died and every fifth patient needed revision within 4 years after surgery. Efforts should be undertaken to provide optimal treatment to these high-risk patients to reduce unfavorable outcomes.

Level of evidence

III.

Registration of clinical trials

As this is a registry-derived study of data of the German Arthroplasty Registry (EPRD), no registration was performed.
On Flamant–Boussinesq problem with dynamical flexoelectric effect and micro-inertia effect in dielectrics subjected to dynamical wave loading
Authors: El-Dhaba A. R. , Ghaleb A. F. , Hilal Mohamed I. M.
Published: July 2023

This work investigates the Flamant–Boussinesq problem for a half-space made of a homogeneous and isotropic dielectric material. The dynamical flexoelectric effect and the dynamical flexocoupling between displacement and polarization, due to mechanical and electrical states, are taken in consideration. The mechanical loading is taken as a wave of a decaying behavior in time at the surface of a half-space, while the electric potential is considered in an open circuit with no charge on the terminals. The first strain gradient theory of elasticity is used as a mathematical frame in the problem formulation. The equation of motion for the representative volume element additionally accounts for the micro-inertia effect because of the intrinsic structure of the dielectrics at the nanoscale. The governing equations and the boundary conditions for homogeneous, isotropic dielectric material are presented with reference to previous work, using a variational technique for internal energies and external forces. An analytical harmonic wave solution is obtained for the problem under consideration, involving different coupling parameters arising from the mechanical and electrical loadings. The results are analyzed and discussed. The solutions for the quantities of practical interest are represented graphically with different choices of material parameters and flexocoupling parameters. The solution is finite everywhere. The existing damping phenomenon arises, not only from the various physical parameters in the governing field equations as shown in the figures, but also through the boundary conditions.
Evaluation and comparison of various methods used for aggregates investigations
Authors: Hołysz Lucyna , Rek Paulina , Huber Miłosz , Terpiłowski Konrad
Published: July 2023

Natural aggregates from sedimentary rock, like limestone and dolomite, are of a great use in various practical applications. To evaluate their quality, among others, the test of methylene blue adsorption (MB value) using a filter paper is recommended. However, one can consider it as a rough test. In this paper we wished to evaluate its quality by comparison with a more precise spectrophotometric method, i.e., to perform adsorption isotherms of methylene blue from aqueous solutions, as well as determine other parameters characterizing the aggregates. For this purpose, methylene blue adsorption on samples of limestone and dolomite natural aggregates having various grain sizes were studied to assess quality (fine particles content) of the manufactured aggregates. To determine the amount of adsorbed dye two methods were used: the methylene blue stain test and the dye adsorption from its solutions at various concentrations under static conditions. From the linear form of Langmuir adsorption isotherms of methylene blue, the monolayer capacity was determined, and then the specific surface areas of all fractions of aggregates. The structural (N2adsorption/desorption), textural (SEM/EDS) and crystallographic structure of the aggregates were studied. It was determined that the MB values for 0–2 andMBFfor 0–0.125 mm aggregates fractions fulfill the criteria set out in the specifications required for pavement construction. A very good repeatability of the adsorbed amount of methylene blue on the dolomite and limestone aggregates were obtained by these two different methods. These results confirm the reliability of the method blue test used typically in industrial conditions. The measured specific surface areas of limestone and dolomite using N2adsorption (SBET) are smaller than SMBdetermined by methylene blue adsorption from aqueous solutions. This is because in aggregates, apart from calcite and dolomite, there is a small admixture of quartz and clay minerals. During N2adsorption in dry condition, the external surface of the grains is determined, while in the aqueous solution of methylene blue, both the external and inner surfaces of clay minerals are determined.
Differences in obesity-related health behaviors and health outcomes by rural and Appalachian residency
Authors: Zhang Xiaochen , Shoben Abigail B. , Felix Ashley S. , Focht Brian C. , Paskett Electra D.
Published: July 2023

Purpose

Obesity and health behaviors are the major modifiable contributors to cancer and health disparities. We examined the differences in obesity-related health behaviors, and health outcomes by rural and Appalachian residency in Ohio.

Methods

Cross-sectional survey data from the 2011–2019 Behavioral Risk Factor Surveillance System were obtained from the Ohio Department of Health. County-level identifiers were used to classify urban non-Appalachian, urban Appalachian, rural non-Appalachian, and rural Appalachian residency. Self-reported weight, height, health behaviors, and health conditions were used. Logistic regression was used to assess the difference in health behaviors and health outcomes by rural and Appalachian residency. All analyses incorporated with sample weights.

Results

Among Ohio residents, compared to urban non-Appalachian residents, urban Appalachian and rural Appalachian residents had a higher prevalence of obesity, hypertension, high cholesterol, and cardiovascular diseases, as well as lower rates of healthy diet and physical activity. No difference was found in trends of obesity and obesity-related health outcomes in 2011–2019 by rural and Appalachian residency. However, rural Appalachian residents had a greater increase in obesity, hypertension, and diabetes, whereas rural non-Appalachian had favorable changes in obesity-related health behaviors. Additionally, associations between health behaviors and obesity-related health outcomes differed by rural and Appalachian residency.

Conclusions

Findings underscore the importance of distinguishing between urban non-Appalachian, urban Appalachian, rural non-Appalachian, and rural Appalachian populations when assessing health disparities. While the trends of obesity and obesity-related health outcomes did not differ, the association between health behaviors and obesity-related outcomes differed by rural and Appalachian residency.
Students’ and teachers’ responses to use of a digital self-assessment tool to understand and identify development of twenty-first century skills when working with makerspace activities
Authors: Walan Susanne , Brink Helen
Published: July 2023

In this qualitative study, we investigated how students and teachers responded to the design of a digital self-assessment tool and how they experienced the use of the tool to support understanding and development of twenty-first century skills when working with makerspace activities. There were 65 lower secondary school students and four teachers participating in the study. We used individual interviews with the teachers and group interviews with the students. Data were analysed with thematic coding of transcripts from interviews. The results showed that the participants found that the tool needed technical improvements, but that they gained some insights into the meaning of the included twenty-first century skills (collaboration, creativity, problem-solving, life/social skills and communication). However, it was particularly difficult for students to understand the meaning of life/social skills and how this connected to makerspace activities. Still, both students and teachers argued that it is possible to develop twenty-first century skills during makerspace activities. Teachers also found connections between the skills and learning objectives in the school subject technology, but also in other subjects. We were unsure of how used students were to self-assessment and we believe that teachers’ role is essential, even when it comes to supporting students in self-assessment. Finally, both students and teachers argued that twenty-first century skills are of importance for the future and the project served as an eye-opener in this aspect.
From uniform to bespoke prices: Hotel pricing during EURO 2016
Authors: Nicolini Marcella , Piga Claudio A. , Pozzi Andrea
Published: July 2023

Using novel data on the pricing for hotel rooms in Paris during the summer of the 2016 European Football Cup, we document the co-existence of uniform and bespoke pricing within the same industry and even within the same firm. Although stay dates have heterogenous potential demand, hotels initially price them uniformly. However, as time goes by, they progressively set customized prices. We show that standard revenue management techniques can explain the shift and find evidence that the inability to form expectations about future demand was a determinant of the initial choice of uniform prices. Finally, we find that firm characteristics have a role in shaping the transition.
Examining Changes in Abortion Attitudes Following the Transition to Parenthood
Authors: Clarke Eden V. , Sibley Chris G. , Osborne Danny
Published: July 2023

The recent reversal of Roe v. Wade in the United States demonstrates both the precarity of reproductive rights and the need to identify the correlates of abortion support. Surprisingly, little is known about how the transition to parenthood impacts attitudes toward abortion. We address this oversight by utilising nine annual waves (2011–2019) of longitudinal panel data to examine rates of change in support for elective and traumatic abortion in the year(s) before and after participants became parents (N = 1,266). Consistent with population trends, support for elective and traumatic abortion increased in the year(s) before participants became parents. After the transition to parenthood, support for elective abortion continued to increase (albeit at a slower rate), whereas traumatic abortion support stopped increasing. These results demonstrate that the process of becoming a parent attenuates the growth of abortion support over time and highlight the need for robust policies that protect reproductive autonomy.
euMMD: efficiently computing the MMD two-sample test statistic for univariate data
Authors: Bodenham Dean A. , Kawahara Yoshinobu
Published: July 2023

The maximum mean discrepancy (MMD) test is a nonparametric kernelised two-sample test that, when using a characteristic kernel, can detect any distributional change between two samples. However, when the total number of $$d$$
d
-dimensional observations is $$n$$
n
, direct computation of the test statistic is $$\mathcal {O}(dn^2 )$$

O
(
d

n
2

)

. While approximations with lower computational complexity are known, more efficient methods for computing the exact test statistic are unknown. This paper provides an exact method for computing the MMD test statistic for the univariate case in $$\mathcal {O}(n\log n)$$

O
(
n
log
n
)

using the Laplacian kernel. Furthermore, this exact method is extended to an approximate method for $$d$$
d
-dimensional real-valued data also with complexity log-linear in the number of observations. Experiments show that this approximate method can have good statistical performance when compared to the exact test, particularly in cases where $$d> n$$

d
>
n

.
Using citizen science data to investigate annual survival rates of resident birds in relation to noise and light pollution
Authors: Pharr Lauren D. , Cooper Caren B. , Evans Brian , Moorman Christopher E. , Voss Margaret A. , Vukomanovic Jelena , Marra Peter P.
Published: July 2023

Exponential increases in anthropogenic noise and light pollution have accompanied growth of the built environment. Noise and light cause negative consequences for birds, such as disrupted navigation during migration, mortality from collisions with windows and other infrastructure, and reduced reproductive success, as well as some positive consequences, such as expanded night niches for behaviors associated with feeding, territoriality, and mating. Relatively less is known about noise and light effects on annual survival of non-migratory birds, so we conducted an exploratory study to examine variation in adult survival rates of seven avian species in relation to noise and light pollution. We used 20 years of band-resight data collected as a part of the Neighborhood Nestwatch Program (NN), a citizen science project run by the Smithsonian Migratory Bird Center, at 242 sites in greater Washington, D.C. USA. We estimated apparent survival and documented species-specific relationships with light and noise. Gray Catbird (Dumetella carolinensis) and House Wren (Thryothorus aedon) survival decreased and American Robin (Turdus migratorius) survival increased with greater amounts of anthropogenic light. Anthropogenic noise had no relationship with apparent survival for any of the seven species. Life-history trade-offs between survival and reproduction may account for differences in species-specific effects of light pollution. Future research should examine the availability of other fine scale environmental conditions, such as tree canopy cover, that might buffer avian exposure to noise and light pollution.
Characterisation of a low methane emission rice cultivar suitable for cultivation in high latitude light and temperature conditions
Authors: Hu Jia , Bettembourg Mathilde , Moreno Silvana , Zhang Ai , Schnürer Anna , Sun Chuanxin , Sundström Jens , Jin Yunkai
Published: July 2023

Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.
Stellate Ganglion Block and Intraarterial Spasmolysis in Patients with Cerebral Vasospasm: A Retrospective Cohort Study
Authors: Wendel Christopher , Oberhauser Cornelia , Schiff Jan , Henkes Hans , Ganslandt Oliver
Published: July 2023

Background

In patients with symptomatic cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage who do not respond to medical therapy, urgent treatment escalation has been suggested to be beneficial for brain tissue at risk. In our routine clinical care setting, we implemented stellate ganglion block (SGB) as a rescue therapy with subsequent escalation to intraarterial spasmolysis (IAS) with milrinone for refractory CV.

Methods

In this retrospective analysis from 2012 to 2021, patients with CV following aneurysmal subarachnoid hemorrhage who received an SGB or IAS were identified. Patients were assessed through neurological examination and transcranial Doppler. Rescue therapy was performed in patients with mean cerebral blood flow velocity (CBFV) ≥ 120 cm/s and persistent neurological deterioration/intubation under induced hypertension. Patients were reassessed after therapy and the following day. The Glasgow Outcome Scale was assessed at discharge and 6-month follow-up.

Results

A total of 82 patients (mean age 50.16 years) with 184 areas treated with SGB and/or IAS met the inclusion criteria; 109 nonaffected areas were extracted as controls. The mean CBFV decrease in the middle cerebral artery on the following day was − 30.1 (± 45.2) cm/s with SGB and − 31.5 (± 45.2) cm/s with IAS. Mixed linear regression proved the significance of the treatment categories; other fixed effects (sex, age, aneurysm treatment modality [clipping or coiling], World Federation of Neurological Surgeons score, and Fisher score) were insignificant. In logistic regression, the presence of cerebral infarction on imaging before discharge from the intensive care unit (34/82) was significantly associated with unfavorable outcomes (Glasgow Outcome Scale ≤ 3) at follow-up.

Conclusions

Stellate ganglion block and IAS decreased CBFV the following 24 h in patients with CV. We suggest SGB alone for patients with mild symptomatic CV (CBFV < 180 cm/s), while subsequent escalation to IAS proved to be beneficial in patients with refractory CV and severe CBFV elevation (CBFV ≥ 180 cm/s).
Outcomes After Decompressive Surgery for Severe Cerebral Venous Sinus Thrombosis Associated or Not Associated with Vaccine-Induced Immune Thrombosis with Thrombocytopenia: A Multicenter Cohort Study
Authors: Pelz Johann Otto , Kenda Martin , Alonso Angelika , Etminan Nima , Wittstock Matthias , Niesen Wolf-Dirk , Lambeck Johann , Güresir Erdem , Wach Johannes , Lampmannn Tim , Dziewas Rainer , Wiedmann Markus , Schneider Hauke , Bayas Antonios , Christ Monika , Mengel Annerose , Poli Sven , Brämer Dirk , Lindner Dirk , Pfrepper Christian , Roth Christian , Salih Farid , Günther Albrecht , Michalski Dominik ,   for the IGNITE Study Group
Published: July 2023

Background

Clinical observations indicated that vaccine-induced immune thrombosis with thrombocytopenia (VITT)-associated cerebral venous sinus thrombosis (CVST) often has a space-occupying effect and thus necessitates decompressive surgery (DS). While comparing with non-VITT CVST, this study explored whether VITT-associated CVST exhibits a more fulminant clinical course, different perioperative and intensive care unit management, and worse long-term outcome.

Methods

This multicenter, retrospective cohort study collected patient data from 12 tertiary centers to address priorly formulated hypotheses concerning the clinical course, the perioperative management with related complications, extracerebral complications, and the functional outcome (modified Rankin Scale) in patients with VITT-associated and non-VITT CVST, both with DS.

Results

Both groups, each with 16 patients, were balanced regarding demographics, kind of clinical symptoms, and radiological findings at hospital admission. Severity of neurological symptoms, assessed with the National Institute of Health Stroke Scale, was similar between groups at admission and before surgery, whereas more patients with VITT-associated CVST showed a relevant midline shift (≥ 4 mm) before surgery (100% vs. 68.8%, p = 0.043). Patients with VITT-associated CVST tended to undergo DS early, i.e., ≤ 24 h after hospital admission (p = 0.077). Patients with VITT-associated CVST more frequently received platelet transfusion, tranexamic acid, and fibrinogen perioperatively. The postoperative management was comparable, and complications were evenly distributed. More patients with VITT-associated CVST achieved a favorable outcome (modified Rankin Scale ≤ 3) at 3 months (p = 0.043).

Conclusions

Although the prediction of individual courses remains challenging, DS should be considered early in VITT-associated CVST because an overall favorable outcome appears achievable in these patients.