bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of gallium surfactant on AlN thin films by microwave plasma chemical vapor deposition
Authors: Wang Lu , Qin Xulei , Zhang Li , Xu Kun , Yang Feng , Lu Shaoqian , Li Yifei , Liu Bosen , Yu Guohao , Zeng Zhongming , Zhang Baoshun
Published: September 2024

In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec.
Effects of 1 MeV electron radiation on the AlGaN/GaN high electron mobility transistors
Authors: Pan Shijie , Feng Shiwei , Li Xuan , Feng Zixuan , Lu Xiaozhuang , Bai Kun , Zhang Yamin
Published: September 2024

In this study, the effects of 1 MeV electron radiation on the D-mode GaN-based high electron mobility transistors (HEMTs) were investigated after different radiation doses. The changes in electrical properties of the device were obtained, and the related physical mechanisms were analyzed. It indicated that under the radiation dose of 5 × 1014 cm−2, the channel current cannot be completely pinched off even if the negative gate voltage was lower than the threshold voltage, and the gate leakage current increased significantly. The emission microscopy and scanning electron microscopy were used to determine the damage location. Besides, the radiation dose was adjusted ranging from 5 × 1012 to 1 × 1014 cm−2, and we noticed that the drain−source current increased and the threshold voltage presented slightly negative shift. By calculations, it suggested that the carrier density and electron mobility gradually increased. It provided a reference for the development of device radiation reinforcement technology.
10 × 10 Ga2O3-based solar-blind UV detector array and imaging characteristic
Authors: Chen Haifeng , Liu Zhanhang , Zhang Yixin , Jia Feilong , Wu Chenlu , Lu Qin , Liu Xiangtai , Wang Shaoqing
Published: September 2024

A 10 × 10 solar-blind ultraviolet (UV) imaging array with double-layer wire structure was prepared based on Ga2O3 film grown by atomic layer deposition. These single detection units in the array exhibit excellent performance at 3 V: photo-to-dark current ratio (PDCR) of 5.5 × 105, responsivity (R) of 4.28 A/W, external quantum efficiency (EQE) of 2.1 × 103%, detectivity (D
*) of 1.5 × 1014 Jones, and fast response time. The photodetector array shows high uniformity under different light intensity and low operating bias. The array also has good temperature stability. Under 300 °C, it still presents clear imaging and keeps high R of 34.4 and 6.45 A/W at 5 and 1 V, respectively. This work provides a new insight for the large-scale array of Ga2O3 solar-blind UV detectors.
Utilizing diffusion tensor imaging as an image biomarker in exploring the therapeutic efficacy of forniceal deep brain stimulation in a mice model of Alzheimer’s disease
Authors: Chen You-Yin , Chang Chih-Ju , Liang Yao-Wen , Tseng Hsin-Yi , Li Ssu-Ju , Chang Ching-Wen , Wu Yen-Ting , Shao Huai-Hsuan , Chen Po-Chun , Lai Ming-Liang , Deng Wen-Chun , Hsu RuSiou , Lo Yu-Chun
Published: September 2024

Objective. With prolonged life expectancy, the incidence of memory deficits, especially in Alzheimer’s disease (AD), has increased. Although multiple treatments have been evaluated, no promising treatment has been found to date. Deep brain stimulation (DBS) of the fornix area was explored as a possible treatment because the fornix is intimately connected to memory-related areas that are vulnerable in AD; however, a proper imaging biomarker for assessing the therapeutic efficiency of forniceal DBS in AD has not been established. Approach. This study assessed the efficacy and safety of DBS by estimating the optimal intersection volume between the volume of tissue activated and the fornix. Utilizing a gold-electroplating process, the microelectrode’s surface area on the neural probe was increased, enhancing charge transfer performance within potential water window limits. Bilateral fornix implantation was conducted in triple-transgenic AD mice (3 × Tg-AD) and wild-type mice (strain: B6129SF1/J), with forniceal DBS administered exclusively to 3 × Tg-AD mice in the DBS-on group. Behavioral tasks, diffusion tensor imaging (DTI), and immunohistochemistry (IHC) were performed in all mice to assess the therapeutic efficacy of forniceal DBS. Main results. The results illustrated that memory deficits and increased anxiety-like behavior in 3 × Tg-AD mice were rescued by forniceal DBS. Furthermore, forniceal DBS positively altered DTI indices, such as increasing fractional anisotropy (FA) and decreasing mean diffusivity (MD), together with reducing microglial cell and astrocyte counts, suggesting a potential causal relationship between revised FA/MD and reduced cell counts in the anterior cingulate cortex, hippocampus, fornix, amygdala, and entorhinal cortex of 3 × Tg-AD mice following forniceal DBS. Significance. The efficacy of forniceal DBS in AD can be indicated by alterations in DTI-based biomarkers reflecting the decreased activation of glial cells, suggesting reduced neural inflammation as evidenced by improvements in memory and anxiety-like behavior.
Cryogel microcarriers loaded with glial cell line-derived neurotrophic factor enhance the engraftment of primary dopaminergic neurons in a rat model of Parkinson’s disease
Authors: Narasimhan Kaushik , Hakami Abrar , Comini Giulia , Patton Tommy , Newland Ben , Dowd Eilís
Published: September 2024

Objective. Cryogel microcarriers made of poly(ethylene glycol) diacrylate and 3-sulfopropyl acrylate have the potential to act as delivery vehicles for long-term retention of neurotrophic factors (NTFs) in the brain. In addition, they can potentially enhance stem cell-derived dopaminergic (DAergic) cell replacement strategies for Parkinson’s disease (PD), by addressing the limitations of variable survival and poor differentiation of the transplanted precursors due to neurotrophic deprivation post-transplantation in the brain. In this context, to develop a proof-of-concept, the aim of this study was to determine the efficacy of glial cell line-derived NTF (GDNF)-loaded cryogel microcarriers by assessing their impact on the survival of, and reinnervation by, primary DAergic grafts after intra-striatal delivery in Parkinsonian rat brains. Approach. Rat embryonic day 14 ventral midbrain cells were transplanted into the 6-hydroxydopamine-lesioned striatum either alone, or with GDNF, or with unloaded cryogel microcarriers, or with GDNF-loaded cryogel microcarriers. Post-mortem, GDNF and tyrosine hydroxylase immunostaining were used to identify retention of the delivered GDNF within the implanted cryogel microcarriers, and to identify the transplanted DAergic neuronal cell bodies and fibres in the brains, respectively. Main results. We found an intact presence of GDNF-stained cryogel microcarriers in graft sites, indicating their ability for long-term retention of the delivered GDNF up to 4 weeks in the brain. This resulted in an enhanced survival (1.9-fold) of, and striatal reinnervation (density & volume) by, the grafted DAergic neurons, in addition to an enhanced sprouting of fibres within graft sites. Significance. This data provides an important proof-of-principle for the beneficial effects of neurotrophin-loaded cryogel microcarriers on engraftment of cells in the context of cell replacement therapy in PD. For clinical translation, further studies will be needed to assess the impact of cryogel microcarriers on the survival and differentiation of stem cell-derived DAergic precursors in Parkinsonian rat brains.
Study of shock shapes around blunted conical bodies in hypersonic flow
Authors: Srikanth Gautam , Hithesh Sai , Anirudh Marella , Yadav Avinash , Kotebavi Vinod
Published: September 2024

The study of supersonic and hypersonic flows remains one of the most complex areas to understand and simulate results, especially due to the various complexities. The objective of this study is to analyze the shock shapes, pressure distributions, coefficient of drag, coefficient of moment, and the shock standoff distance for hypersonic flow over blunted conical bodies. The density-based approach and implicit method have been used as they are the most suitable for compressible flows. A grid-independent study has been performed to ensure the results are independent of grid size. The simulations are performed for cones with different semi-apex angles and shoulder radii. The Mach number is varied from 5 to 10. Results are validated with the theoretical results obtained from empirical relations. It has been observed that as the apex angle increases, values of drag, moment coefficient, and the shock standoff distance increases. It was also observed that for a cone of given apex angle, as the Mach number increases, the values of drag coefficient and moment coefficient increases and the shock sstandoff distance decreases. The maximum increase in the drag on increasing the cone angle is 8.44%, and the maximum reduction in drag on increasing Mach number is 1.27%.
Comparison of turbulent models for baffled stirred tank
Authors: Mathew Sibin V , Supradeepan K , Sankar Ganesh P
Published: September 2024

Fluid mixing in stirred tanks is an extensively researched domain in various process industries. A stirred tank uses an impeller to agitate the fluid, inducing turbulent regions that significantly enhance the mixing process. Understanding the fluid dynamics in an agitated vessel can be achieved through both experimental and numerical methods. The present work utilized Computational Fluid Dynamics(CFD) to analyze flow fields within an agitated vessel. The study focuses on evaluating the effectiveness of various Reynolds Averaged Navier-Stokes(RANS) models to estimate flow characteristics within a stirred tank. The geometry comprises a cylindrical tank stirred by a Rushton impeller at 100 rpm. To enhance mixing efficiency, four baffles are affixed to the lateral surface of the tank, generating recirculating flows. The tank is filled with water up to the top wall to prevent vortex formation. Open-source CFD software, OpenFOAM®, is utilized for performing simulations. The study investigated mean velocity components, power number, Root Mean Square (RMS), and Reynolds stress profiles of the stirred tank. The realizable k − ε model exhibited superior performance compared to other RANS models in predicting flow parameters of baffled stirred tanks under specified flow conditions considered in this investigation.
Mitigating Temperature Heterogeneity in Cold Storage: A Numerical Investigation Using a Cassette Fan Coil Unit for Air Flow Distribution
Authors: Daniel Alexander Leo , Jakhar Sanjeev , Sankar Dasgupta Mani
Published: September 2024

Inadequate storage conditions for agricultural harvests can result in significant economic losses. Cold storage plays a crucial role in preserving horticultural produce, where proper airflow distribution is essential for maintaining freshness. Ceiling-mounted Fan Coil Units (CM-FCUs), commonly used in cold storages, may lead to uneven temperatures among crates. This study proposes evaluating the suitability of Cassette-type Fan Coil Units (CT-FCUs) in cold storages to enhance airflow and cooling rates. Cold storage with CM-FCUs was modeled, simulated, and validated using experimental data. A similar cold storage with CT-FCUs was also modeled and simulated, and various thermal performance parameters were compared. In the proposed system, the maximum area-weighted average velocity was observed to be 20.5% higher than in the conventional cold storage. Similarly, the Performance Index (PI) demonstrated a 41.1% improvement, while temperature heterogeneity was 41.3% lower compared to the CM-FCU, indicating superior thermal performance in the cold storage with CT-FCUs. These findings suggest that the proposed CT-FCUs outperformed the CM-FCUs in terms of thermal performance.
Investigation of the Petition-fuel production as HHO-gas through developed electrolyser by using the mathematical model with experimental performance analysis
Authors: Kumar Nayak Amiya , Kumar Rout Akshaya , Kumar Dewangan Akhilesh , Sagar Sinha Gyan
Published: September 2024

This paper examines the design of an electrolyser model, comparing it with mathematical and experimental models. The model involves passing an electric current through water dissolved with an alkylamine-ethoxylate compound, resulting in the release of oxygen and hydrogen, forming Oxy-hydrogen gas. The gas generation rate of the generated HHO-gas is predicted using the mathematical and experimental models. The experiment investigates factors such as Faraday efficiency, power, compound concentration in water, and hydrogen concentration in HHO-gas at different operating temperatures. The alkylamine ethoxylate is a compound composed of cationic, anionic, and non-anionic surfactants, with a concentration range of 15% to 60%. The model shows a power consumption range of 72% to 88% with operating temperatures of 30 to 80 degrees Celsius. The electrode disc plates have an internal distance of 2.5 mm to 1.2 mm and are connected to a negative and positive terminal. The results show a remarkable level of agreement between the experimental results and the mathematical model, indicating that gas generators consistently provide the specified output across various operational circumstances.
Towards Sustainable Mobility: A Framework and Strategies for Rural Transportation Sustainability
Authors: Sankar Das Shiv , Debadatta Behera Debashree , Bijeta Nayak Bijaya , Kumar Patjoshi Pramod , Chandra Mohanty Ramesh
Published: September 2024

In the recent times, the issues of resource depletion, rapid urbanization, and climate change have focused on the need for sustainable solutions in the area of mobility. While significant importance has been made in urban areas towards sustainable transportation, rural areas face unique challenges that require strategies. The scarcity of resources, limited infrastructure, and the impact of climate change demand a dedicated focus on developing sustainable transportation frameworks in rural settings. The objective of the study is to develop a framework for sustainable transportation in rural areas and strategies for sustainable transportation in rural areas. The study also focuses on developing the relationships between the different components of the framework and it reflects on community driven solutions for achieving sustainable mobility in the rural areas such as solar-powered electric rickshaws, bicycle-sharing programs, community-run shuttle services, etc. Secondary data has been collected for understanding the theoretical concepts. Under the present study, project reports, articles and books were used as secondary sources. Descriptive case study method is used for application of the framework.
Experimental study of the thermal efficiency of Solar air heater equipped with rotating spiral shape baffles: Using Solar Simulator
Authors: Khimsuriya Yogeshkumar D. , Patel D. K. , Patel Vivek , Panchal Hitesh , Kumar Kaushik Lav
Published: September 2024

This study investigates the thermal performance of a Solar Air Heater (SAH) equipped with rotating spiral-shaped baffles, utilizing a solar simulator. Parameters such as relative roughness pitch (P/e) and Reynolds number (Re) were varied within the ranges of 4-10 and 4000-12000, respectively, with a fixed relative roughness height (e/H) of 0.8. The fabricated solar simulator, adhering to EN-12975-2 standards, demonstrated excellent irradiance homogeneity at approximately 10.47%, resulting in an average solar irradiance of 955 W/m2. The introduction of artificial roughness on the absorber plate significantly enhanced the SAH’s thermal performance. The study further revealed a correlation between Re and plate temperature, highlighting the impact on heat transfer. Notably, the configuration with a smooth plate exhibited the highest plate temperatures, while the absorber plate with P/e–8 displayed the lowest plate temperatures across varying Re. An increase in Re corresponded to a distinct rise in outlet temperature, with the P/e–8 setup exhibiting the most significant temperature difference, reaching 4.9°C at a Re of 12000. Additionally, the configuration featuring a roughened plate with P/e-8 achieved the highest thermal efficiency at 61.03% at a Re of 12000, showcasing a substantial 64.86% improvement compared to the smooth absorber plate. These findings contribute valuable insights for optimizing the design and performance of solar air heating systems.
Bamboo as a Potential Eco-Friendly Composite – A Review
Authors: Rashmi Sarmah Richa , Neog Dipankar
Published: September 2024

Bamboo, as a potential ecological structural material, has gained a lot of attention, due to its wide distribution i.e., more than 1000 species; short growth cycle of 3-5 years; high stiffness and better fibre strength. The amalgamation of matrix and natural fibres like bamboo gives rise to composites that yield best properties of each component. These properties include the enhancement in mechanical, thermal, morphological and chemical properties of the bamboo composite. Keeping in mind its growth in different fields, this work puts light on explored areas of bamboo reinforced composite and their related performances observed by different researchers from time to time. From this review, an idea can be generated as to where one can apply such material for optimal results in near future.
Scenarios of Waste Management in Indian Context: A Brief Review on E-waste and Biomedical waste
Authors: Kumar Singhdeo Ashok , Tripathy Sushanta , Singhal Deepak
Published: September 2024

Human day to day activities produce a wide range of remarkable wastes that come from a number of sources. Cleaning up contamination in wastes over a longer period of time is far more expensive than preventing it at the source. Various nations have an uphill battle in correctly managing their waste, with the majority of efforts aimed at reducing final quantities and raising sufficient money for waste management. With the growing importance of waste management, it has become an absolute necessity for every nation to have the combined duty of people, industry, local governments, and pollution control boards. The main purpose of this review is to find out more about the different ways that electronic and biomedical wastes are handled in India by looking at a lot of different cases.
LCA-based strategic evaluation for building renovation construction projects
Authors: Alvise Bragadin Marco , Calistri Mattia , Predari Giorgia
Published: September 2024

It is well known that the existing building stock needs performance upgrades related to energy retrofit. In Italy and many European countries seismic structural safety standards requirements are also increasing, and therefore together with other renovation works, a structural rehabilitation is always needed. Structural rehabilitation is generally an invasive intervention on the structural sub-system, while energy redevelopment is less invasive as it is mostly performed in the building envelope, but it is economically relevant. Therefore, the high renovation costs and the limitation of the usability of the building during a renovation project often lead real estate developers to choose the easier strategy of complete demolition and reconstruction. This can be, perhaps, the easiest choice but, from an environmental and economic point of view, usually the least sustainable one. Environmental sustainability can be evaluated via the Life Cycle Assessment (LCA) approach, but LCA needs a complete evaluation of the existing and new building systems, sub-systems and components. Therefore, the strategic choice based upon LCA can usually be performed only late in the design process, when most of the technologic systems have been designed in detail. A parametric preliminary evaluation can help project managers and real estate developers to choose the most environmentally sustainable design alternative, even with a low level of knowledge of the existing building. The proposed approach uses a list of parametric costs for a building type to extract preliminary data about building quantities. Therefore, a mixed method that uses typical cost plans and existing LCA database is proposed to perform the preliminary LCA analysis of a building renovation project and evaluate sustainability.
Complexity in project studies: A rhetorical device perspective
Authors: Frederiksen N , Gottlieb S C , de Gier A , Bronke J , Primdahl M B , Klitgaard A , Koch C
Published: September 2024

A frequently used term in project studies is that of complexity. This term typically conveys the presence of multiple intricate and interrelated project factors that render prediction, and ultimately performance, challenging. Complexity is ubiquitous in the context of projects, and there are competing notions of complexity and, consequently, how to cope with it. Drawing on an integrative review approach, we explore four predominant notions of complexity in project studies, provide examples of illustrative research-based constructs (root metaphors) associated with each, and discuss their differences. In doing so, we first explore Bent Flyvbjerg’s idea about the “Iron Law of Mega-Projects” as an example of complexity inherent in the project environment. Next, Martin Barnes’ proposal of the “Iron Triangle” serves as an example of complexity inherent in the project. Then, Kristian Kreiner’s “Drifting Environments” concept is used as an example of complexity emerging in the project environment. Finally, Albert Hirschman’s idea about the “Hiding Hand” serves as an example of complexity emerging in the project. After exploring the four notions, we discuss how each can serve as a potential rhetorical devise for creating relationships and reasoning between complexity and project (mis-)performance. Based on the study, we suggest that complexity in project studies, despite its linguistic grounding, exhibits polysemy in the sense that it is associated with a multitude of notions and connotations. This polysemy both obscures the phenomenon of complexity while offering a plethora of opportunities for rhetorically linking and justifying project conditions and project (mis-)performance.
Importance of client presence for safety in renewable energy construction and rehabilitation projects
Authors: Holen Siri , Eide Ingeborg , Albrechtsen Eirik
Published: September 2024

The construction industry is known to be hazardous for its workers, being the industry with one of the highest injury rates. A number of studies show that leadership engagement in construction projects influence safety, however, the importance of how the client management role is carried out with regards to physical presence over time during construction has not been in focus. The aim of the study is to understand how safety is influenced by the presence of client personnel on construction sites related to renewable energy and the effects of their presence. Insights from both the client and contractor perspectives are provided, based on eighteen semi-structured interviews. The results show that degree of presence is determined by the project managers in early stages of the projects and this decision is based on factors such as economy risk assessment, knowledge transfer and projects size and complexity. Three main factors that stem from client’s presence are found to influence safety; i) increased monitoring which leads to higher risk awareness, ii) increased local knowledge which leads to identifying valuable solutions to issues and iii) shorter communication paths reduce uncertainty and positively impacts progress. Identified challenges regarding client’s presence are related to over-involvement and becoming blind to hazards. In conclusion, the client personnel’s onsite presence is important for creating a shared understating between client and contractor of safety issues, something that is not possible through remote collaboration, and especially important when projects increase in complexity.
The Impacts of the Tampere Tramway Project
Authors: Vainio Terttu , Nippala Eero
Published: September 2024

Light Rail transport within the city has become an interesting form of public transport in many cities in Europe as well as in other parts of the world. According to the experience of the reference cities, light rail or tramway is primarily an urban development project, not only a public transport project. This case study focuses on the indirect impacts of a tramway project. Do they really happen or is their valuation just a means to achieve political will. The city of Tampere is one of a few growing cities in Finland. The growth of the city caused congestion in the city centre, where the bus lines either ended or whose pendulum lines passed. Project planning for the Tampere tramway started in the early 2000s, construction began in 2017, traffic on the first lines started in 2021. In the tramway, the decisions are based on future expectations. In our research, we assess how well these expectations have been realised in the Tampere tramway project by means of a literature survey and statistical comparisons. The developments to be considered are the direct and indirect investments in the construction of the tramway, the demographic changes, and the housing markets. The evaluation material consists of official regional statistics. According to evaluation, the land use of Tampere has become more efficient than expected in the area affected by the tramway. Not only on empty plots, but also old low commercial buildings have been replaced by high new residential buildings. The tramway has supported urban development by attracting investors to build on previously for abandoned plots. The main street of Tampere is dedicated to the tram, a limited number of buses and light traffic, so congestion has been reduced.
Construction Workers’ Perception of Project Management, Work Environment, and Health & Safety
Authors: Wandahl S. , Pérez C. T. , Salling S. T.
Published: September 2024

The construction industry is labor-intensive, where project performance relies on a successful collaboration between construction workers between workers and managers. Hence, knowledge about workers’ job satisfaction is highly valuable for improving the efficiency of the construction industry. For that reason, a survey was conducted to understand construction workers’ perceptions of factors that influence job satisfaction. The questionnaire included 12 demographic questions and 27 questions. Data was collected in 2023, and almost 3400 workers answered the questionnaire. Several relevant insights surfaced during the data analysis. Among others, the more the workers are engaged and involved in planning, the higher the performance and job satisfaction. The more digital tools are used, the better performance and job satisfaction. However, workers find that digital tools are used too little. The younger workforce is more troubled than the older.
An Integrated Framework for Digital Twins in Hospitals
Authors: Pedral Sampaio Rodrigo , Aguiar Costa António , Flores-Colen Inês , Johanne Klungseth Nora , Giovanni Semini Marco , Nordvik Sondre
Published: September 2024

The architecture, engineering, construction, and facility management (AECFM) industry has been criticized for having a level of digitalization far below that of other manufacturing sectors, especially in creating digital assets, expanding digital tools, and creating digital jobs. The challenge of managing the built environment is currently particularly complex, considering the increasing performance requirements not only in terms of energy and the environment but also from a human perspective. Digital twin technology, with its ability to create virtual replicas of physical assets, has gained significant traction in the built environment sector. These virtual twins offer immense potential for monitoring, simulation, and optimization. Nonetheless, to fully harness their benefits, an integrated framework is essential. Such a framework would guide seamless implementation, interoperability, and effective utilization of digital twins across various domains. Several questions may arise when we create a digital twin for the built environment: How should we structure the digital twin model? What information should we be able to visualize? How should the digital twin model interact with the user? These are some of the questions we still need a consistent answer. A mixed-methods approach that combined a literature review with with expert interviews was used to understand better the current state of digital twin applications in the built environment sector. This study emphasizes the significance of using an integrated approach to develop digital twin technology to realize its full potential in the built environment industry. It puts forward a framework specifically designed for hospital facilities.
Normal-normal continuous symmetric stresses in mixed finite element elasticity
Authors: Carstensen Carsten , Heuer Norbert
Published: September 2024

The classical continuous mixed formulation of linear elasticity with pointwise symmetric stresses allows for a conforming finite element discretization with piecewise polynomials of degree at least three. Symmetric stress approximations of lower polynomial order are only possible when their

div
\operatorname {div}

-conformity is weakened to the continuity of normal-normal components. In two dimensions, this condition is meant pointwise along edges for piecewise polynomials, but a corresponding characterization for general piecewise

H
(
div
)

H(\operatorname {div})

tensors has been elusive.

We introduce such a space and establish a continuous mixed formulation of linear planar elasticity with pointwise symmetric stresses that have, in a distributional sense, continuous normal-normal components across the edges of a shape-regular triangulation. The displacement is split into an

L
2

L_2

field and a tangential trace on the skeleton of the mesh. The well-posedness of the new mixed formulation follows with a duality lemma relating the normal-normal continuous stresses with the tangential traces of displacements.

For this new formulation we present a lowest-order conforming discretization. Stresses are approximated by piecewise quadratic symmetric tensors, whereas displacements are discretized by piecewise linear polynomials. The tangential displacement trace acts as a Lagrange multiplier and guarantees global

div
\operatorname {div}

-conformity in the limit as the mesh-size tends to zero. We prove locking-free, quasi-optimal convergence of our scheme and illustrate this with numerical examples.
Two grasses differ in their absorptive root physiological traits and rooting depth under drought in an alpine steppe
Authors: Zheng Zhi , Zhang Yurui , Li Ziyue , Dong Feifei , Chen Lijuan
Published: September 2024

Background and Aims

Absorptive root traits play important roles in acquisition of water and nutrients from soil by plants. Despite numerous reports on the changes in species dominance under long-term drought in grassland communities, few studies have specifically investigated absorptive root traits of these dominant species in grasslands, especially in alpine grasslands.

Methods

Here, two grass species (Leymus secalinus and Stipa purpurea) differing in their responses to drought were selected from an alpine steppe. A series of absorptive root traits were examined under drought in a 3-year glasshouse experiment.

Key Results

We found that drought had no effects on root morphological and architectural traits, whereas root physiological traits and rooting depth differed in their responses to drought. Specifically, drought significantly reduced root respiration and enhanced organ carbon (C) exudation rate, carboxylate exudation rate, acid phosphatase activity and rooting depth of L. secalinus. In particular, L. secalinus released more citrate into the rhizosphere under drought than S. purpurea. In contrast, these root traits of S. purpurea remained relatively unchanged in response to the drought. These differential responses would render L. secalinus more competitive in acquisition of nutrients and water, thus contributing to its dominance in the community under drought. Moreover, root respiration was negatively correlated with organic C exudation rate, carboxylate exudation rate and acid phosphatase activity, indicating a trade-off between root respiration and root exudates to acquire nutrients and water by optimizing C allocation under drought. Additionally, all root traits exhibited two independent dimensions in root economic space for both species under drought.

Conclusions

These results indicate that the plant species with great capacity to acquire water and nutrients in soil by optimizing C allocation under drought will be dominant in the community of the alpine grasslands. These findings provide an important insight into species re-ordering under drought on the Tibetan Plateau.
Mycosis fungoides: an unwelcome guest in my life
Authors: Grechin Cristina , Yoo Li Jie Helena , Ryan Stephanie Lynn , Ní Raghallaigh Síona
Published: September 2024

Mycosis fungoides (MF) is a cutaneous T-cell lymphoma. Despite its relatively good prognosis, with high survival rates, the literature shows that MF may cause a significant deterioration in a patient’s quality of life due to uncertainty regarding disease progression. Our patient’s perspective highlights the significant impact that MF has had on his quality of life. We hope that this report serves as a reminder to dermatologists and other healthcare professionals that it is important to consider the psychological impact that can be associated with a diagnosis of MF. Living with and managing MF successfully is a challenge for the patient and the physician.
Preludes to friendship: improvisatory instrumental souvenirs in 19th-century autograph albums
Authors: Zohn Steven
Published: September 2024

Among the musical souvenirs found in 19th-century autograph or friendship albums is an overlooked repertory of improvisatory pieces for solo string and wind instruments. These cadenzas, capriccios and preludes were given to collectors by some of the leading performers of the day, including violinists Charles-Auguste de Bériot, Ole Bull, Ferdinand David, Joseph Joachim and Niccolò Paganini; and flautists Louis Drouët and Jean-Louis Tulou. Most of these pieces are found nowhere else, and because they include precise indications of date and place, some can be connected to specific performances. As musical self-portraits, they capture their authors’ personalities and artistry in strikingly varied ways: from visually extravagant (and occasionally humorous) roulades, to bel canto ‘vocal’ cadenzas and more extended flights of fancy. Taken as a whole, this repertory brings us a step or two closer to what was heard in salons and concert halls than the more familiar repertory of published cadenzas, capriccios and preludes.
Carbapenemase and extended-spectrum beta-lactamase-producing bacteria in waters originating from a single landfill in Slovenia
Authors: Tkalec Valerija , Lindic Polona , Jursa Tatjana , Ivanusa Sket Hermina , Maric Leon , Cimerman Mojca , Rupnik Maja , Golle Andrej
Published: September 2024

Groundwater, rainwater, and leachate associated with a single landfill were analysed to detect extended-spectrum beta-lactamase (ESBL)-producing and carbapenemase (CP)-producing bacteria. After cultivation on three commercial selective-differential media, 240 bacterial isolates were obtained and identified by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Isolates from clinically relevant species were further genotyped by enterobacterial repetitive intergenic consensus polymerase chain reaction, and tested for antibiotic susceptibility and presence of CPs and ESBL enzymes. Two ESBL-producing isolates and two isolates producing CPs were detected in rainwater, groundwater, and leachate: Klebsiella oxytoca complex with the gene for the ESBL enzyme CTX-M-1 and the gene for the CP OXA-48, Serratia fonticola with the gene for the ESBL enzyme FONA-2, and Pseudomonas aeruginosa with the gene coding Verona integron-encoded Metallo-beta-lactamases (VIM) metallo-beta-lactamase. Our study indicates that bacteria with ESBL and CP genes can be present in landfill-associated waters.
The purely iterative conception of set
Authors: Klev Ansten
Published: September 2024

According to the iterative conception of set, sets are formed in stages. According to the purely iterative conception of set, sets are formed by iterated application of a set-of operation. The cumulative hierarchy is a mathematical realization of the iterative conception of set. A mathematical realization of the purely iterative conception can be found in Peter Aczel’s type-theoretic model of constructive set theory. I will explain Aczel’s model construction in a way that presupposes no previous familiarity with the theories on which it is based.
Is the use of neuromonitoring necessary in Sprengel’s deformity surgery?
Authors: Akar Abdulhalim , Sever Gokhan Bulent , Akturk Umut Dogu , Serttas Muhammed Fatih , Ozdemir Ugur , Tekin Omer Faruk , Aydogan Mehmet
Published: September 2024

This study aimed to emphasize the effectiveness of using intraoperative neuromonitoring (IONM) in preventing possible nerve damage in Sprengel’s deformity surgery. Eighteen patients who underwent Woodward surgery accompanied by neuromonitoring due to Sprengel’s deformity were included in the study. Demographic information of the patients and their clinical and cosmetic results before and after surgery were recorded. Complications that occurred during and after the surgery were recorded. Of the 18 patients who underwent surgery, 12 were female and 6 were male. The mean age of the patients was 4.4 (2–8). The mean shoulder abduction angle of the patients was 84.4 (65–105) degrees before the surgery and 151.1 (125–175) degrees in the first year after the surgery. The mean Cavendish score of the patients was 3.6 (3–4) before the surgery and 1.1 (1–2) in the first year after the surgery. In one patient, there was a decrease in IONM motor-evoked potency signals during the reduction of the intraoperative scapula. Considering some loss of correction in the deformity, the scapula was detected at the point where there was no loss of signals. No patients developed wound problems or infections. In this study, it was determined that the use of neuromonitoring was effective in preventing brachial plexus damage, even if this complication was minimal in patients operated on due to Sprengel’s deformity.
Comparison of the differential effect of participation in breast cancer screening program versus opportunistic screening or symptomatic detection on tumour characteristics
Authors: Laza-Vásquez Celmira , Rué-Monné Montserrat , Fougo José Luís , Peleteiro Bárbara
Published: September 2024

Objectives

The success of a breast cancer screening program is highly dependent on adherence. We aimed to compare the differential effect of participation in breast cancer screening program versus opportunistic screening or symptomatic detection on tumour characteristics.

Methods

We included women referred to our Breast Centre in 2015–2021: 321 from the breast cancer screening group (group 1) and 422 through opportunistic screening or due to symptomatic detection (group 2). We compared data on sociodemographics, breast cancer detection, clinical features and tumour characteristics.

Results

A total of 10.6% of women in group 1 had breast symptoms and 63.8% had breast signs, with group 2 presenting higher proportions (57.6 and 77.8%, respectively, P < 0.001). The median tumour size in group 1 was smaller compared with group 2 (14 vs 17 mm, P < 0.001). A total of 8.7% of women in group 1 had nodal involvement whereas in group 2 the proportion corresponded to 19.0% (P < 0.001). No women in group 1 were diagnosed with metastasis, while metastases were found in 2.4% of those from group 2 (P = 0.005). There were no significant differences in molecular subtype of invasive tumours between the two groups.

Conclusion

The tumour characteristics of women who participated in the breast cancer screening program showed in almost all characteristics more favourable results in comparison with the group who underwent opportunistic screening or sought care due to symptoms. The lower clinical stage observed in those referred from the organised program reaffirms that it is an effective measure for early detection, diagnosis, and treatment.
Global epidemiology of liver cancer 2022: An emphasis on geographic disparities
Authors: Li Qianru , Ding Chao , Cao Maomao , Yang Fan , Yan Xinxin , He Siyi , Cao Mengdi , Zhang Shaoli , Teng Yi , Tan Nuopei , Wang Jiachen , Xia Changfa , Chen Wanqing
Published: September 2024

Background:

Liver cancer remains the sixth most commonly diagnosed cancer and the third leading cause of cancer-related deaths worldwide, causing a heavy burden globally. An updated assessment of the global epidemiology of the liver cancer burden that addresses geographical disparities is necessary to better understand and promote healthcare delivery.

Methods:

Data were extracted from the GLOBOCAN 2022 database, including the number, crude, and age-standardized rates of incidence and mortality at the global, country, continent, and human development index (HDI) regional levels. Age-standardized rates (incidence and mortality) per 100,000 person-years were adjusted based on the Segi-Doll World standard population. The mortality-to-incidence ratios (MIR) for each region and country were calculated. The HDI and gross national income (GNI) for 2022 were obtained, and a Pearson correlation analysis was conducted with the incidence, mortality, and MIR.

Results:

In 2022, approximately 866,136 new liver cancer cases and 758,725 related deaths were recorded worldwide, with a global MIR of 0.86. Males had a disproportionately higher burden than females across all levels, and the highest burden was observed in the elderly population. Geographically, the regions with the highest incidence rates included Micronesia, Eastern Asia, and Northern Africa, and the regions with the highest mortality rates included Northern Africa, Southeastern Asia, Eastern Asia, and Micronesia. Notably, Mongolia had a strikingly high burden compared to other countries. The highest MIR was observed in North America and the lowest in Africa. Negative associations of HDI and GNI with liver cancer mortality and MIR were identified, irrespective of sex.

Conclusions:

The current liver cancer burden underscores the presence of remarkable geographic heterogeneity, which is particularly evident across countries with varying HDI levels, highlighting the urgent need to prioritize health accessibility and availability to achieve health inequities.
Maternal Health During the COVID-19 Pandemic in the United States: An Interrupted Time-series Analysis
Authors: Jackson Kaitlyn , Karasek Deborah , Gemmill Alison , Collin Daniel F. , Hamad Rita
Published: September 2024

Background:

The COVID-19 pandemic, and subsequent policy responses aimed at curbing disease spread and reducing economic fallout, had far-reaching consequences for maternal health. There has been little research to our knowledge on enduring disruptions to maternal health trends beyond the early pandemic and limited understanding of how these impacted pre-existing disparities in maternal health.

Methods:

We leveraged rigorous interrupted time-series methods and US National Center for Health Statistics Vital Statistics Birth Data Files of all live births for 2015–2021 (N = 24,653,848). We estimated whether changes in maternal health trends after the onset of the COVID-19 pandemic (March 2020) differed from predictions based on pre-existing temporal trends. Outcomes included gestational diabetes, hypertensive disorders of pregnancy, gestational weight gain, and adequacy of prenatal care.

Results:

We found an increased incidence of gestational diabetes (December 2020 peak: 1.7 percentage points (pp); 95% confidence interval [CI]: 1.3, 2.1), hypertensive disorders of pregnancy (January 2021 peak: 1.3 pp; 95% CI: 0.4, 2.1), and gestational weight gain (March 2021 peak: 0.1 standard deviation; 95% CI: 0.03, 0.1) and declines in inadequate prenatal care (January 2021 nadir: −0.4 pp; 95% CI: −0.7, −0.1). Key differences by subgroups included greater and more sustained increases in gestational diabetes among Black, Hispanic, and less educated individuals.

Conclusion:

These patterns in maternal health likely reflect not only effects of COVID-19 infection but also changes in healthcare access, health behaviors, remote work, economic security, and maternal stress. Further research about causal pathways and longer-term trends will inform public health and clinical interventions to address maternal disease burden and disparities.
Rheumatoid arthritis presented in an 89-year-old woman: a case report
Authors: Kudsi Maysoun , Alghawe Fatima , Haidar Ghina , Hadid Batoul , Btrush Sana
Published: September 2024

Introduction and importance:

Elderly onset rheumatoid arthritis (EORA) is defined as the onset of rheumatoid arthritis (RA) in individuals over 60 years and presents unique clinical features. Nonsteroidal anti-inflammatory drugs and disease-modifying antirheumatic drugs are introduced immediately after the diagnosis is proven. In some cases, biological treatment may be used. We present a case report of EORA in an 89-year-old female.

Case presentation:

An 89-year-old Syrian female presented with fatigue, fever, generalized arthralgia, and myalgia, with morning stiffness of more than 1 hour for 3 months. On physical examination, she had bilateral joint tenderness and swelling of more than 10 small joints. Laboratory tests revealed anemia and elevated inflammatory markers with a high titer of rheumatoid factor and anti-cytoplasmic citrullinated peptide (anti-CCP). Diagnosis of RA was confirmed, and she was put on prednisolone, methotrexate, and paracetamol. After 6 months, our patient’s clinical examination and laboratory tests had returned to normal.

Clinical discussion:

About 70% of EORA cases have joint erosions, positive rheumatoid factor, and a worse prognosis, and 25% of EORA cases mimic polymyalgia rheumatic, with a favorable prognosis. EORA has a poor outcome, due to the risk of infection and comorbidities.

Conclusion:

Our patient presented with symptoms mimicking polymyalgia rheumatica (PMR), so a definitive diagnosis is required between elderly RA and PMR due to their different treatment and complications. Medical professionals should consider a diagnosis of RA in elderly patients, regardless of their age.