bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcome Measures of Open versus Minimally Invasive Surgery for Thoracolumbar Spinal Traumatic Fractures: A Systematic Review and Meta-Analysis
Authors: Esposito Felice , Bove Ilaria , Vitulli Francesca , Bocchino Andrea , Barbanera Andrea , Nape Stefania , Lombardi Sara , Raffa Giovanni , Pintore Luigi , Palmiero Carmela , Fellico Fabrizio , Solari Domenico , Cavallo Luigi Maria , Somma Teresa
Published: September 2024

Objective: To evaluate the efficacy of open and percutaneous pedicle screw fixation in the treatment of thoracolumbar fractures. Methods: Online databases MEDLINE (PubMed), SCOPUS, and Cochrane were searched for English language articles published between January 2001 and December 2023, limited to articles that included the clinical and radiological outcomes of adult patients. The main outcome measures of the study were the Oswestry Disability Index (ODI), the Numeric Rating Scale (NRS) score, and the Cobb angle. Results: A total of 7 studies involving 909 patients were included; 374 (41.1%) procedures were performed with open surgery (OS), while 535 (58.9%) procedures were conducted with minimally invasive surgery (MIS). The mean value of ODI in the MIS group was 8.29% [CI 95% 4.82–11.76], compared to the other group, which was 14.22% (p-value 0.87). Patients receiving a MIS had an average NRS of 1.54 [CI95% 0.98–2.10] whilst OS had 2.31 [CI95% 1.50–3.12] (p-value 0.12). Conclusions: The percutaneous technique is equally safe and effective in resolving the deformity, but the clear advantages are represented by the reduction in blood loss, shorter operative times, a lower incidence of infection, shorter hospitalization, shorter postoperative rehabilitation, and therefore good results in terms of quality of life.
Target Heart Rate Formulas for Exercise Stress Testing: What Is the Evidence?
Authors: Almaadawy Omar , Uretsky Barry F. , Krittanawong Chayakrit , Birnbaum Yochai
Published: September 2024

Exercise stress testing (EST) is commonly used to evaluate chest pain, with some labs using 85% of age-predicted maximum heart rate (APMHR) as an endpoint for EST. The APMHR is often calculated using the formula 220-age. However, the accuracy of this formula and 85% APMHR as an endpoint may be questioned. Moreover, failing to reach 85% APMHR (known as chronotropic insufficiency) may also indicate poor cardiovascular prognosis, but measurements, such as percentage heart rate reserve (%HRR), maximum rate pressure product (MRPP), and the maximum metabolic equivalent of tasks (METs) reached during EST may provide better prediction of cardiovascular outcomes than not reaching 85% of APMHR. There is a need to incorporate comprehensive measurements to improve the diagnostic and prognostic capabilities of EST.
Long COVID Cardiopulmonary Symptoms and Health Resort Treatment: A Retrospective Study
Authors: Onik Grzegorz , Knapik Katarzyna , Sieroń Karolina
Published: September 2024

Background/Objectives: Long COVID covers many cardio-pulmonary symptoms, worsening individuals’ health status. Health resort treatment applies balneological factors, physical medicine modalities, climate actions, and exercises that may be beneficial for COVID-19 survivors. This study aimed to assess the severity of the cardiopulmonary symptoms in people qualified for health resort treatment and its efficacy in this group of patients. Methods: Medical records of 239 people attending health resort treatment were analysed. A total of 122 people (71 women and 51 men) with a mean age of 64.35 years ± 8.66 years were enrolled in the analysis. The cardiopulmonary symptoms of long COVID were assessed twice: before and after health resort treatment. Results: Persisting COVID-19 symptoms do not differentiate between women and men. Health resort treatment reduces symptoms severity in both sexes. Age does not mediate the efficacy of health resort treatment. Conclusions: The persistent symptoms of COVID-19 are of low intensity in people qualified for health resort treatment and are independent of gender. Health resort treatment effectively mitigates dyspnoea, tightness of chest, and sputum in long COVID patients, so it should be implemented into the standard treatment course for COVID-19 survivors as a continuation of therapy.
The Hydrodynamic Similarity between Different Power Levels and a Dynamic Analysis of Ocean Current Energy Converter–Platform Systems with a Novel Pulley–Traction Rope Design for Irregular Typhoon Waves and Currents
Authors: Lin Shueei-Muh , Wang Wen-Rong , Yuan Hsin
Published: September 2024

In the future, the power of a commercial ocean current energy convertor will be able to reach the MW class, and its corresponding mooring rope tension will be very good. However, the power of convertors currently being researched is still at the KW class, which can bear less rope tension. The main mooring rope usually has a single cable and a single foundation. To investigate the dynamic response and rope tension of an MW-class ocean current generator mooring system, here, a similarity rule is proposed for (1) coefficients without any fluid–structure interaction (FSI) using the Buckingham theorem and (2) ones with FSI. The overall hydrodynamic drag and moment including the hydrodynamic coefficients in these two situations are represented in a Taylor series. Assuming similarity between the commercial MW-class and KW-class ocean current convertors, all hydrodynamic parameters of the MW-class system are estimated based on the known KW-class parameters and based on the similarity formula. In order to overcome the extreme tension of the MW-class system and to provide good stability, in this paper, we propose a pulley–rope design to replace the traditional single-traction-rope design. The static and dynamic mathematical models of this mooring system subjected to the impact of typhoon waves and currents are proposed, and analytical solutions are obtained. We find that the pulley–rope design can significantly reduce the dynamic rope tensions of the mooring system. The effect of the length ratio of the main traction rope, rope A, to the seabed depth on the dynamic tension of stabilizing converter rope D is significant. The length ratio is within a safe range, and the maximum rope dynamic tension is less than the fracture strength. In addition, if the rope length ratio is over the critical value, the larger the ratio, the higher the safety factor of the rope. In summary, the pulley–rope design can be safely used in an MW-level ocean current generator system.
Three-Dimensional Path Planning of UAVs for Offshore Rescue Based on a Modified Coati Optimization Algorithm
Authors: Miao Fahui , Li Hangyu , Mei Xiaojun
Published: September 2024

Unmanned aerial vehicles (UAVs) provide efficient and flexible means for maritime emergency rescue, with path planning being a critical technology in this context. Most existing unmanned device research focuses on land-based path planning in two-dimensional planes, which fails to fully leverage the aerial advantages of UAVs and does not accurately describe offshore environments. Therefore, this paper establishes a three-dimensional offshore environmental model. The UAV’s path in this environment is achieved through a novel swarm intelligence algorithm, which is based on the coati optimization algorithm (COA). New strategies are introduced to address potential issues within the COA, thereby solving the problem of UAV path planning in complex offshore environments. The proposed OCLCOA introduces a dynamic opposition-based search to address the population separation problem in the COA and incorporates a covariance search strategy to enhance its exploitation capabilities. To simulate the actual environment as closely as possible, the environmental model established in this paper considers three environmental factors: offshore flight-restricted area, island terrain, and sea winds. A corresponding cost function is designed to evaluate the path length and path deflection and quantify the impact of these three environmental factors on the UAV. Experimental results verify that the proposed algorithm effectively solves the UAV path planning problem in offshore environments.
Colletotrichum Species Associated with Apple Bitter Rot and Glomerella Leaf Spot: A Comprehensive Overview
Authors: Trkulja Vojislav , Čojić Bojana , Trkulja Nenad , Tomić Andrija , Matić Slavica , Ikanović Jela , Popović Milovanović Tatjana
Published: September 2024

Species of the genus Colletotrichum are among the most important plant pathogens globally, as they are capable of infecting many hosts—apple (Malus spp.) and other fruit and woody plant species—but also vegetable crops, cereals, legumes, and other annual and perennial herbaceous plants. The apple (Malus spp.) is attacked by various species from the genus Colletotrichum, whereby 27 different species from this genus have been described as the causative agents of apple bitter rot (ABR) and 15 as the cause of Glomerella leaf spot (GLS). These species generally belong to one of three species complexes: Colletotrichum acutatum, Colletotrichum gloeosporioides, and Colletotrichum boninense. The largest number of apple pathogens of the genus Colletotrichum belong to the species complex C. acutatum and C. gloeosporioides. However, further data on these species and the interactions between the species complexes of the genus Colletotrichum that cause these two apple diseases is needed for the development of effective control measures, thus ensuring successful and profitable apple cultivation. To contribute to this endeavor, a comprehensive review of the causative agents of ABR and GLS from the genus Colletotrichum is provided. In addition to presenting the species’ current names, distribution, economic significance, and the symptoms they cause in apple, their development cycle, epidemiology, and molecular detection strategies are described, with a particular emphasis on control measures.
A Cross-Layer Approach to Analyzing Energy Consumption and Lifetime of a Wireless Sensor Node
Authors: Ojeda Fernando , Mendez Diego , Fajardo Arturo , Becker Maximilian Gottfried , Ellinger Frank
Published: September 2024

Several wireless communication technologies, including Wireless Sensor Networks (WSNs), are essential for Internet of Things (IoT) applications. WSNs employ a layered framework to govern data exchanges between sender and recipient, which facilitates the establishment of rules and standards. However, in this conventional framework, network data sharing is limited to directly stacked layers, allowing manufacturers to develop proprietary protocols while impeding WSN optimization, such as energy consumption minimization, due to non-directly stacked layer effects on network performance. A Cross-Layer (CL) framework addresses implementation, modeling, and design challenges in IoT systems by allowing unrestricted data and parameter sharing between non-stacked layers. This holistic approach captures system dynamics, enabling network design optimization to address IoT network challenges. This paper introduces a novel CL modeling methodology for wireless communication systems, which is applied in two case studies to develop models for estimating energy consumption metrics, including node and network lifetime. Each case study validates the resulting model through experimental tests, demonstrating high accuracy with less than 3% error.
Predictive Maintenance in IoT-Monitored Systems for Fault Prevention
Authors: Zero Enrico , Sallak Mohamed , Sacile Roberto
Published: September 2024

This paper focuses on predictive maintenance for simple machinery systems monitored by the Internet of Things (IoT). As these systems can be challenging to model due to their complexity, diverse typologies, and limited operational lifespans, traditional predictive maintenance approaches face obstacles due to the lack of extensive historical data. To address this issue, we propose a novel clustering-based process that identifies potential machinery faults. The proposed approach lies in empowering decision-makers to define predictive maintenance policies based on the reliability of the proposed fault classification. Through a case study involving real sensor data from the doors of a transportation vehicle, specifically a bus, we demonstrate the practical applicability and effectiveness of our method in preemptively preventing faults and enhancing maintenance practices. By leveraging IoT sensor data and employing clustering techniques, our approach offers a promising avenue for cost-effective predictive maintenance strategies in simple machinery systems. As part of the quality assurance, a comparison between the predictive maintenance model for a simple machinery system, pattern recognition neural network, and support vector machine approaches has been conducted. For the last two methods, the performance is lower than the first one proposed.
The Influence of a Personalized Intervention Program—AGA@4life—in the Cardiovascular Diseases: A Biochemical Approach
Authors: Soares Maria , Freitas Catarina , Timoteo Maria , Lourenço Ana , Ferreira Ana , Figueiredo João , Pereira Telmo , Caseiro Armando
Published: September 2024

Aging is a complex process inherent to and inevitable in humans. With life expectancy rising, there are concerns about the senior population’s wellbeing, and a hope of preventing certain diseases such as cardiovascular diseases. To achieve it, this study resorts to the implementation of an interventional program based on the comprehensive geriatric assessment model [AGA@4life]. The aim is to evaluate the effect of a new nutritional and exercise regime and evaluate possible changes in nitric oxide (NO) metabolites and endothelin 1 (ET-1). An intervention study was developed with 17 participants with ages of 65 and above. They were evaluated in the beginning [T0] and after eight weeks [T1], where NO metabolites and ET-1 levels were determined by enzymatic assays and the slot blot technique, respectively. There was a significant decrease in ET-1 levels in both the control (p < 0.001) and intervention (p = 0.04) groups from T0 to T1, but there was only a tendency for a decrease in the NO metabolite’s levels in the same conditions [p > 0.05]. Even though the NO metabolite levels did not increase as expected, possibly because of an increase in oxidative stress, the ET-1 levels decreased as expected and the overall results are promising, proving this program could have a beneficial effect on the geriatric population.
The Impact of Green Finance on Agricultural Non-Point Source Pollution: Analysis of the Role of Environmental Regulation and Rural Land Transfer
Authors: Geng Guobin , Shen Yang , Dong Chenguang
Published: September 2024

This study evaluates the impact of green finance on agricultural non-point source pollution control and emission reduction in 30 Chinese provinces from 2005 to 2022. Utilizing the entropy value method and the unit survey inventory method, the research measures the levels of green finance development and agricultural non-point source pollution. It employs a mediation effect model to empirically assess the pollution control efficacy of green finance and to elucidate the mechanisms underlying its influence. The findings indicate that green finance development significantly curtails agricultural non-point source pollution emissions. This conclusion is still valid after a series of robustness tests. The results of mechanism analysis show that environmental regulation and land transfer are important channels for green finance to reduce agricultural non-point source pollution. However, the slowing effect of green finance is stronger in provinces where the economic development level is still in the catch-up zone. Consequently, this study suggests strengthening green finance infrastructure in rural areas, coordinating green finance and environmental regulation policies, optimizing land transfer systems to promote scale management, and developing differentiated green finance policies based on regional economic development levels. These measures aim to augment the role of green finance in pollution treatment and emission reduction, thereby optimizing the green financial system, advancing environmental protection, and fostering sustainable development in China’s agricultural sector.
An Investigation into the Mechanism of Government Embedment and Organizational Environment Influencing Farmers’ Credible Commitment in Regard to the Collective Governance of Rural Residential Land
Authors: Yang Zhongjian , Tang Hong , Jin Jiafang , Ran Ruiping
Published: September 2024

The purpose of this study is to investigate the influence of Government Embedment and Organizational Environment on farmers’ Credible Commitment in regard to the Collective Governance of Rural Residential Land and to inform decision-making processes that promote farmers’ compliance with Rural Residential Land management regulations and enhance the effectiveness of the Collective Governance of Rural Residential Land. The research employs various models, including Oprobit, Ologit, IV-2SLS, and moderated mediation. The research results show that (1) both Government Embedment and the Cultural Environment within the Organizational Context significantly enhance Farmers’ Credible Commitment in regard to the Collective Governance of Rural Residential Land. Notably, the quality of the Cultural Environment, when improved by Government Embedment, boosts this commitment further. (2) Endogeneity issues can lead to an overestimation of the effects of these factors. (3) Punishment intensity only positively moderates the impact of the Cultural Environment on Farmers’ Credible Commitment. (4) The moderating effect of punishment intensity correlates positively with its strength, exhibiting a threshold value. In conclusion, our research underscores the need to establish a robust regulatory framework for Rural Residential Land use, foster a conducive village cultural atmosphere, and consistently enhance the punishment intensity for illegal Rural Residential Land use. These measures will encourage farmers to adhere to Credible Commitment in regard to Rural Residential Land use, thereby facilitating the effective implementation of Collective Governance over Rural Residential Land.
The Role of Social Inclusion in Restoring Communal Rangelands in Southern Africa: A Systematic Review of Approaches, Challenges, and Outcomes
Authors: Slayi Mhlangabezi , Zhou Leocadia , Thamaga Kgabo Humphrey , Nyambo Patrick
Published: September 2024

Rangeland restoration in southern Africa faces complex challenges that require the involvement of diverse social groups to ensure both ecological and social sustainability. This systematic review focuses on the role of social inclusion in rangeland restoration across multiple countries in the region, specifically examining the engagement of marginalized groups such as women, youth, and indigenous communities. We conducted a comprehensive search using the PRISMA approach, utilizing Scopus and other literature sources. Initially, we found 853 articles published between 2000 and 2024, which were subsequently screened down to 20 studies that met stringent inclusion criteria. This review identifies key strategies and outcomes associated with social inclusion in restoration efforts. Our findings reveal that participatory planning, gender-inclusive strategies, indigenous engagement, and capacity building are crucial for gaining community support, promoting social equity, and enhancing ecological resilience. However, challenges such as power dynamics, cultural norms, and resource constraints often impede the full realization of these inclusive practices. Despite these barriers, integrating local and indigenous knowledge and empowering marginalized groups significantly strengthens governance structures and leads to more sustainable restoration outcomes. Our review highlights the necessity of adopting holistic and inclusive approaches in rangeland restoration where social inclusion is not just a component but a central pillar of successful ecological management. It emphasizes the importance of social inclusion in the restoration of communal rangelands in southern Africa and provides insights into the approaches used, challenges faced, and outcomes achieved in incorporating social inclusion in rangeland restoration efforts. Our findings underscore the significance of collaborative efforts and social inclusion among local communities, policymakers, and stakeholders to achieve the sustainable restoration of communal rangelands in southern Africa.
The Influence of Urban Design Performance on Walkability in Cultural Heritage Sites of Isfahan, Iran
Authors: Maniei Hessameddin , Askarizad Reza , Pourzakarya Maryam , Gruehn Dietwald
Published: September 2024

This research explores the impact of urban design performance qualities on pedestrian behavior in a cultural heritage site designated by UNESCO. The study employs a multi-method approach, including a questionnaire survey, empirical observation of pedestrian activities, and empirical axial line and visibility graph analysis using the space syntax technique. The first part of the study involved a questionnaire formatted as a polling sheet to gather expert assessments of spatial performance measures. The second part used a pilot survey to capture the perspectives of end users regarding the study’s objectives and their perceptions of the site. Pedestrian flow was observed using a technique called “gate counts”, with observations recorded as video clips during specific morning and afternoon periods across three pedestrian zones. The study also examined the behavioral patterns of pedestrians, including their movement patterns. Finally, the ArcGIS 10.3.1 software was employed to evaluate the reliability of the results. The main finding of this research is that pedestrian behavior and walkability in the historical areas are significantly influenced by landmark integration, wayfinding behavior, and the socio-economic functions of heritage sites. This study highlights the importance of using cognitive and syntactic analysis, community engagement, and historical preservation to enhance walkability, accessibility, and social interaction in heritage contexts. In addition, it identifies the need for improvements in urban design to address inconsistencies between syntactic maps and actual pedestrian flow, emphasizing the role of imageability and the impact of environmental and aesthetic factors on pedestrian movement. This research provides valuable insights for urban designers and planners, environmental psychologists, architects, and policymakers by highlighting the key elements that make urban spaces walkable, aiming to enhance the quality of public spaces.
A Longitudinal Exploration of Perception and Production of English Codas in CLIL Settings
Authors: Gallardo-del-Puerto Francisco , Gómez-Lacabex Esther
Published: September 2024

Second language speech perception and production remain an enduring concern in second language acquisition, as research evidence seems to suggest that there is not a straightforward correspondence between these two speech domains and that their interrelationship seems to be of a complex nature. The present proposal intends to contribute to the inspection of such a relationship by observing the development of perception and production skills of English codas longitudinally in a group of secondary school learners in Spain involved in a content and language integrated learning (CLIL) program, which increases exposure and production opportunities. Results point to a slight overall improvement of both sound perception and production skills during a two-year period, the coda sounds exhibiting variable realizations. Many coda sounds were found to be identified and produced at near/ceiling levels while other codas remained at less successful identification and production levels even after two years of CLIL exposure. The correlation analyses performed indicated that the two dimensions tended to correlate when the development for each coda sound was inspected. No correlations were found when students’ individual overall performance in each dimension were examined, attesting individual differences.
Parameters Tailoring on the Deposition of Hydroxyapatite by Pulsed Electrical Discharge
Authors: Laptoiu Stefan Alexandru , Cojocaru Mihai Ovidiu , Miculescu Marian , Branzei Mihai
Published: September 2024

The creation of strong adhesive layers of hydroxyapatite-based bioceramics (with or without bioinert metals, such as Ta, Ag, and Ti) on biocompatible metallic supports enhances the local biofunctionalization of surfaces. The processing of electroconductive materials using electrical impulse discharges is versatile, enabling precise coating of selected areas with perfectly adherent layers of varying thicknesses. This study aims to quantify the effects of varying the electrical power from the source generating the impulse discharge and the specific processing time per unit area of the cathode (made of titanium alloy) on the relative mass increase of the cathode. The anode comprised a mixture of hydroxyapatite powder and a self-polymerizing electroconductive acrylic resin in a tantalum sheath. The effects of the parameter adjustments on single-layer deposition adherence were quantified using a central composite design to build a second-order orthogonal model. The most significant difference in relative mass was observed with a low-power source (5 W) ensuring the electrical discharge impulse, combined with the longest specified surface treatment time (17.5 s/cm2 on a 4 cm2 surface) for a single layer presenting the largest mass increase of 0.153% of the original mass. This study aimed to enhance the performance of medical implants by optimizing surface biofunctionalization through robust hydroxyapatite-based bioceramic adhesive layers on metallic supports, determining the optimal electrical power and processing time for cathode mass increase during deposition processes, and analyzing parameter adjustments using second-order statistical orthogonal central composite programming, with a focus on single-layer deposition to identify significant differences in relative mass under specific conditions.
Optimization and Analysis of Refill Friction Stir Spot Welding (RFSSW) Parameters of Dissimilar Aluminum Alloy Joints by FE and ANN Methods
Authors: Bîrsan Dan Cătălin , Susac Florin , Teodor Virgil Gabriel
Published: September 2024

The quality of the refill friction stir spot welding (RFSSW) process is heavily dependent on the selected welding parameters that influence the resultant joint characteristics. Thermomechanical phenomena integral to the process were investigated using finite element (FE) analysis on two dissimilar materials. This FE analysis was subsequently validated through controlled experiments to ensure reliability. An artificial neural network (ANN) was employed to create a neural model based on an experimental setup involving 120 different sets of welding parameters. The parameters adjusted in the experimental plan included pin penetration depth, rotational speed, retention time, and positioning relative to material hardness. To assess the neural model’s accuracy, outputs such as maximum temperature and normal stress at the end of the welding process were analyzed and validated by six data sets selected for their uniform distribution across the training domain.
Janus Monolayer of 1T-TaSSe: A Computational Study
Authors: Szałowski Karol
Published: September 2024

Materials exhibiting charge density waves are attracting increasing attention owing to their complex physics and potential for applications. In this paper, we present a computational, first principles-based study of the Janus monolayer of 1T-TaSSe transition metal dichalcogenide. We extensively compare the results with those obtained for parent compounds, TaS2 and TaSe2 monolayers, with confirmed presence of 13×13 charge density waves. The structural and electronic properties of the normal (undistorted) phase and distorted phase with 13×13 periodic lattice distortion are discussed. In particular, for a normal phase, the emergence of dipolar moment due to symmetry breaking is demonstrated, and its sensitivity to an external electric field perpendicular to the monolayer is investigated. Moreover, the appearance of imaginary energy phonon modes suggesting structural instability is shown. For the distorted phase, we predict the presence of a flat, weakly dispersive band related to the appearance of charge density waves, similar to the one observed in parent compounds. The results suggest a novel platform for studying charge density waves in two-dimensional transition metal dichalcogenides.
A Study on the Liquid Helium Temperature Tensile Property of Fe-21Cr-15Ni-5Mn-2Mo Austenitic Stainless Steel after Solution Treatment
Authors: Zhang Mengxing , Wang Changjun , Ma Dangshen , Liu Yu , Wang Weijun , Liang Jianxiong , Fang Chao , Chu Weihan , Huang Chuanjun
Published: September 2024

A novel non-magnetic Fe-21Cr-15Ni-5Mn-2Mo austenitic stainless steel with high strength and plasticity has been developed. The microstructure and liquid helium temperature (4.2 K) tensile properties of the top and bottom samples of large-size forged flat steel after solution treatment at 1090 °C were investigated. The results showed that the average grain size of the bottom sample (48.0 ± 6.7 μm) was smaller than that of the top sample (58.8 ± 15.3 μm), and the MX precipitates and Z phases were distributed in the matrix of the samples. The 4.2 K strengths of the samples at the top and bottom were high, and large amounts of annealing twin boundaries played a certain role in strengthening. After cryogenic tensile testing, large amounts of deformation twins, stacking faults, and dislocations were generated inside the austenite grains of both samples, which helped the material to obtain higher plasticity and strength. The top and bottom samples possessed excellent synergies of strength and plasticity at 4.2 K, and the 4.2 K tensile properties of the top sample were as follows: ultimate tensile strength (UTS) of 1850 MPa, yield strength (YS) of 1363 MPa, and elongation (EL) of 26%. The tested steel is thus believed to meet the requirements of combined excellent strength and plasticity within a deep cryogenic environment, and it would be a promising material candidate for manufacturing superconducting coil cases to serve in new generation fusion engineering.
Effect of Casting Process and Thermal Exposure on Microstructure and Mechanical Properties of Al-Si-Cu-Ni Alloy
Authors: Xiao Peijie , Xu Shiwei , Chen Longbao , Liu Yu , Li Jianyu , Xiao Zhi , Meng Xianming
Published: September 2024

This paper employed squeeze-casting (SC) technology to develop a novel Al-7Si-1.5Cu-1.2Ni-0.4Mg-0.3Mn-0.15Ti heat-resistant alloy, addressing the issue of low room/high temperature elongation in traditional gravity casting (GC). Initially, the effects of SC and GC processes on the microstructure and properties of the alloy were investigated, followed by an examination of the evolution of the microstructure and properties of the SC samples over thermal exposure time. The results indicate that the SC process significantly improves the alloy’s microstructure. Compared to the GC alloy, the secondary dendrite arm spacing of the as-cast SC alloy is refined from 50.5 μm to 18.5 μm. Meanwhile, the size and roundness of the eutectic Si phase in the T6-treated SC alloy are optimized from 11.7 μm and 0.75 μm to 9.5 μm and 0.85 μm, respectively, and casting defects such as porosity are reduced. Consequently, the ultimate tensile strengths (UTSs) at room temperature and at 250 °C of the SC alloy are 5% and 4.9% higher than that of GC alloy, respectively, and its elongation at both temperatures shows significant improvement. After thermal exposure at 250 °C for 120 h, the morphology of the residual second phase at the grain boundaries in the SC alloy becomes more rounded, but the eutectic Si and nano-precipitates undergo significant coarsening, resulting in a 49% decrease in UTS.
Electrical Conductivity, Thermo-Mechanical Properties, and Cytotoxicity of Poly(3,4-Ethylenedioxythiophene):Poly(Styrene Sulfonate) (PEDOT:PSS)/Sulfonated Polyurethane Blends
Authors: Kaur Gagan , Collis Gavin E. , Adhikari Raju , Gunatillake Pathiraja
Published: September 2024

Electrically conductive polymeric materials have recently garnered significant interest from researchers due to their potential applications in the biomedical field, including medical implants, tissue engineering, flexible electronic devices, and biosensors. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered the most successful conducting polymer due to its higher electrical conductivity and chemical stability, but it suffers from limited solubility in common organic solvents, poor mechanical properties, and low biocompatibility. An area of tremendous interest is in combining PEDOT:PSS with another polymer to form a blend or composite material in order to access the beneficial properties of both materials. However, the hydrophilic nature of PEDOT:PSS makes it difficult to produce composites with non-polar polymers. In order to overcome these problems, we have specifically designed and synthesized two new sulfonated polyurethanes (PUS) with high sulfonic acid functionality. The two polyurethanes, one water-soluble (PUS1) and one water-insoluble (PUS2), were used to make blends with two commercially available PEDOT:PSS formulations (CleviosTM FET and PH1000). Solvent cast films on glass substrates were made from water-soluble PEDOT:PSS/PUS1 blends while free-standing films of PEDOT:PSS/PUS2 blends were fabricated by compression-moulding. Ethylene glycol was used as conductivity enhancer, which showed an increase in the conductivity by several orders of magnitude in most of the compositions investigated. The highest conductivity of 438 S cm−1 was achieved for the blend with 80 wt% of PEDOT:PSS (PH1000) in PUS1.
Microstructure and Mechanical Properties of As-Built Ti-6Al-4V and Ti-6Al-7Nb Alloys Produced by Selective Laser Melting Technology
Authors: Laskowska Dorota , Bałasz Błażej , Zawadka Wojciech
Published: September 2024

Additive manufacturing from metal powders using selective laser melting technology is gaining increasing interest in various industries. The purpose of this study was to determine the effect of changes in process parameter values on the relative density, microstructure and mechanical properties of Ti-6Al-4V and Ti-6Al-7Nb alloy samples. The experiment was conducted in response to a noticeable gap in the research on the manufacturability of the Ti-6Al-7Nb alloy in SLM technology. This topic is significant given the growing interest in this alloy for biomedical applications. The results of this study indicate that by properly selecting the volumetric energy density (VED), the relative density of the material produced and the surface roughness of the components can be effectively influenced. Microstructural analyses revealed similar patterns in both alloys manufactured under similar conditions, characterized by columnar β phase grains with needle-like α’ phases. Increasing the VED increased the tensile strength of the fabricated Ti-6Al-4V alloy components, while the opposite effect was observed for components fabricated from Ti-6Al-7Nb alloy. At the same time, Ti-6Al-7Nb alloy parts featured higher elongation values, which is desirable from the perspective of biomedical applications.
Exopolysaccharide (EPS) Produced by Leuconostoc mesenteroides SJC113: Characterization of Functional and Technological Properties and Application in Fat-Free Cheese
Authors: Jurášková Dominika , Ribeiro Susana C. , Bastos Rita , Coelho Elisabete , Coimbra Manuel A. , Silva Célia C. G.
Published: September 2024

A Leuconostoc mesenteroides strain (SJC113) isolated from cheese curd was found to produce large amounts of a mucoid exopolysaccharide (EPS). An analysis revealed the glucan nature of the EPS with 84.5% (1→6)-linked α-d-glucose units and 5.6% (1,3→6)-linked α-d-glucose units as branching points. The EPS showed 52% dextranase resistance and a yield of 7.4 ± 0.9 g/L from MRS medium supplemented with 10% sucrose within 48 h. Ln. mesenteroides SJC113 was also characterized and tested for the production of EPS as a fat substitute in fresh cheese. Strain SJC113 showed high tolerance to a wide range of NaCl concentrations (2, 5 and 10%), high β-galactosidase activity (2368 ± 24 Miller units), cholesterol-reducing ability (14.8 ± 4.1%), free radical scavenging activity (11.7 ± 0.7%) and hydroxyl scavenging activity (15.7 ± 0.4%). The strain had no virulence genes and was sensitive to clinically important antibiotics such as ampicillin, tetracycline and chloramphenicol. Ln. mesenteroides SJC113 produced highly viscous EPS during storage at 8 °C in skim milk with 5% sucrose. Therefore, these conditions were used for EPS production in skim milk before incorporation into fresh cheese. Four types of fresh cheese were produced: full-fat cheese (FF) made from pasteurized whole milk, non-fat cheese (NF) made from pasteurized skim milk, non-fat cheese made from skim milk fermented with Ln. mesenteroides without added sugar (NFLn0) and non-fat cheese made from skim milk fermented with Ln. mesenteroides with 5% sucrose (NFLn5). While the NF cheeses had the highest viscosity and hardness, the NFLn5 cheeses showed lower firmness and viscosity, higher water-holding capacity and lower weight loss during storage. Overall, the NFLn5 cheeses had similar rheological properties to full-fat cheeses with a low degree of syneresis. It was thus shown that the glucan-type EPS produced by Ln. mesenteroides SJC113 can successfully replace fat without altering the texture of fresh cheese.
LMKCDEY Revisited: Speeding Up Blind Rotation with Signed Evaluation Keys
Authors: Lee Yongwoo
Published: September 2024

Recently, Lee et al. introduced a novel blind rotation technique utilizing ring automorphisms also known as LMKCDEY. Among known prominent blind rotation methods, LMKCDEY stands out because of its minimal key size and efficient runtime for arbitrary secret keys, although Chillotti et al.’s approach, commonly referred to as CGGI, offers faster runtime when using binary or ternary secrets. In this paper, we propose an enhancement to LMKCDEY’s runtime by incorporating auxiliary keys that encrypt the negated values of secret key elements. Our method not only achieves faster execution than LMKCDEY but also maintains a smaller key size compared to the ternary version of CGGI. Moreover, the proposed technique is compatible with LMKCDEY with only minimal adjustments. Experimental results with OpenFHE demonstrate that our approach can improve bootstrapping runtime by 5–28%, depending on the chosen parameters.
Three Weak Solutions for a Critical Non-Local Problem with Strong Singularity in High Dimension
Authors: Cunha Gabriel Neves , Faraci Francesca , Silva Kaye
Published: September 2024

In this paper, we deal with a strongly singular problem involving a non-local operator, a critical nonlinearity, and a subcritical perturbation. We apply techniques from non-smooth analysis to the energy functional, in combination with the study of the topological properties of the sublevels of its smooth part, to prove the existence of three weak solutions: two points of local minimum and a third one as a mountain pass critical point.
A Combined OCBA–AIC Method for Stochastic Variable Selection in Data Envelopment Analysis
Authors: Deng Qiang
Published: September 2024

This study introduces a novel approach to enhance variable selection in Data Envelopment Analysis (DEA), especially in stochastic environments where efficiency estimation is inherently complex. To address these challenges, we propose a game cross-DEA model to refine efficiency estimation. Additionally, we integrate the Akaike Information Criterion (AIC) with the Optimal Computing Budget Allocation (OCBA) technique, creating a hybrid method named OCBA–AIC. This innovative method efficiently allocates computational resources for stochastic variable selection. Our numerical analysis indicates that OCBA–AIC surpasses existing methods, achieving a lower AIC value. We also present two real-world case studies that demonstrate the effectiveness of our approach in ranking suppliers and tourism companies under uncertainty by selecting the most suitable partners. This research enriches the understanding of efficiency measurement in DEA and makes a substantial contribution to the field of performance management and decision-making in stochastic contexts.
On LP-Kenmotsu Manifold with Regard to Generalized Symmetric Metric Connection of Type (α, β)
Authors: Prakasha Doddabhadrappla Gowda , Bin Turki Nasser , Veerabhadraswamy Deepika Mathad , Ünal İnan
Published: September 2024

In the current article, we examine Lorentzian para-Kenmotsu (shortly, LP-Kenmotsu) manifolds with regard to the generalized symmetric metric connection ∇G of type (α,β). First, we obtain the expressions for curvature tensor, Ricci tensor and scalar curvature of an LP-Kenmotsu manifold with regard to the connection ∇G. Next, we analyze LP-Kenmotsu manifolds equipped with the connection ∇G that are locally symmetric, Ricci semi-symmetric, and φ-Ricci symmetric and also demonstrated that in all these situations the manifold is an Einstein one with regard to the connection ∇G. Moreover, we obtain some conclusions about projectively flat, projectively semi-symmetric and φ-projectively flat LP-Kenmotsu manifolds concerning the connection ∇G along with several consequences through corollaries. Ultimately, we provide a 5-dimensional LP-Kenmotsu manifold example to validate the derived expressions.
Characterizing Human Peripheral Blood Lymphocyte Phenotypes and Their Correlations with Body Composition in Normal-Weight, Overweight, and Obese Healthy Young Adults
Authors: Kosovski Irina-Bianca , Ciurea Cristina Nicoleta , Ghiga Dana , Ciurea Naomi-Adina , Huțanu Adina , Gliga Florina Ioana , Bacârea Anca
Published: September 2024

Background and Objectives: Obesity-associated chronic low-grade inflammation supports various systemic alterations. In this descriptive study, 122 apparently healthy adults aged 20 to 35 years were voluntarily included and classified based on body mass index (BMI) as normal-weight (NW), overweight (OW), and obese (OB). This study aims to characterize peripheral blood (PB) lymphocyte (Ly) phenotypes and investigate their correlations with body composition indices (BCIs) in healthy young adults. Materials and Methods: The following BCIs were measured: waist circumference, hip circumference, height, waist-to-hip ratio, waist-to-height ratio, total body fat mass, visceral fat level, weight, and BMI. White blood cell count (WBC), Ly absolute count, serum TNF-α, and IFN-γ were quantified. Ly subpopulations were analyzed as follows: total TLy (TTLy—CD45+CD3+), early activated TLy (EATLy—CD45+3+69+), total NKLy (TNKLy—CD45+CD3−CD56+CD16+), NKdim (low expression of CD56+), NKbright (high expression of CD56+), BLy (CD45+CD3−CD19+), T helper Ly (ThLy—CD45+CD3+CD4+), and T cytotoxic Ly (TcLy—CD45+CD3+CD8+). Results: Higher BMI has significantly higher WBC and BLy (p < 0.0001; p = 0.0085). EATLy significantly decreased from NW to OB (3.10—NW, 1.10—OW, 0.85—OB, p < 0.0001). Only EATLy exhibited significant negative correlations with all the BCIs. A significantly higher TNF-α was observed in the OW and OB groups compared to the NW group. IFN-γ increased linearly but nonsignificantly with BMI. TTLy showed a nonsignificant positive correlation with both IFN-γ and TNF-α, while EATLy showed a negative correlation, significant only for IFN-γ. NKLy subpopulations exhibited a consistent negative correlation with TNF-α, significant only for NKdim (p = 0.0423), and a nonsignificant consistent positive correlation with IFN-γ. A nonsignificant negative correlation between age and both TNKLy (r = −0.0927) and NKdim (r = −0.0893) cells was found, while a positive correlation was found with NKbright (r = 0.0583). Conclusions: In conclusion, the baseline immunological profile of PB is influenced by excessive adipose tissue in healthy young adults.
The Impact of a Topical Oxygen-Releasing Gel (blue®m) on Deep Periodontal Pockets: A Case Report
Authors: Alayadi Haya , Talakey Arwa , Aldulaijan Hajer , Shaheen Marwa Y.
Published: September 2024

Periodontitis represents a prevalent oral pathological condition. Various supplementary local therapies are utilized in clinical practice. Recently introduced, topical oxygen therapy exhibits the potential to effectively hinder the growth of plaque (bacterial biofilm). Delivered in the form of an oral gel, this formulation contains cellulose, glycerol, and sodium peroxoborate, releasing topical oxygen in a regulated manner. Additionally, it discharges topical oxygen and lactoferrin in a controlled manner, with the former showcasing antibacterial properties and the latter stimulating bone cell activity. The primary objective of this particular case study is to present a scenario of periodontitis featuring deep periodontal pockets, which was effectively managed through clinical treatment with the use of adjunctive topical oxygen-releasing gel (blue®m).
Assessment of the Probiotic Properties of Yarrowia lipolytica Isolated from Cold-Pressed Olive Oil
Authors: Keskin Pınar , Kılıç Kanak Eda , Öztürk Yılmaz Suzan
Published: September 2024

This research aimed to identify the probiotic features of Yarrowia lipolytica strains isolated from olive oils in Turkey. The in vitro survival capabilities of Y. lipolytica strains in gastric and pancreatic solutions were assessed. The hydrophobicity of Y. lipolytica strains was determined to be between 25.8% and 46.08% for xylene, 22.5% and 45.85% for chloroform, and 14.83% and 37.09% for ethyl acetate. In addition, auto-aggregation values were measured as 11.07–60.35%; 16.28–67.70% and 42.89–85.21% after 2, 4 and 24 h of incubation, respectively. The Y. lipolytica strains tested in this study demonstrated aggregation ability against the pathogens Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028, Staphylococcus aureus ATCC 25923 and Listeria monocytogenes ATCC 7644. Antibiotic resistance and hemolytic activities were also checked to ensure the safety of the Y. lipolytica. Cholesterol removal by Y. lipolytica strains ranged from 12.30% to 47.42%, and their free radical scavenging activity varied between 2.85% and 39.10%. Out of 13 Y. lipolytica samples from 10 different olive oil sources, Y. lipolytica Y6, Y7, and Y11 exhibited the best strains with probiotic potential properties. This study discovered that Y. lipolytica with probiotic properties can be isolated in olive oil samples, a finding that has not been previously documented in the literature and may have potential industrial applications