bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of HDPE geocells for drainage channel coating to replace reinforced concrete structures
Authors: Toniato Andrade Letícia , Todescan Bruna , Caressato Junior Wladimir
Published: September 2024

Typically water conduction channels are lined with reinforced concrete structures. Often, such alternatives consume high construction costs and percentages of total investments destined for water infrastructure and maintenance. In this context, the function of engineering is to seek alternatives that allow, in a responsible and safe manner, to replace typical reinforced concrete structures, focusing on technical and economic aspects. Thus, the use of High Density Polyethylene (HDPE) geocells filled with concrete, to line channels, is intended to facilitate and accelerate the installation of this system, providing a good result, mainly due to its constructive simplicity. In addition, the technology in HDPE geocells is sufficiently stable to withstand the external forces generated on the fluid conduction structures, thus dispensing with the use of steel reinforcement, in addition to formwork, expansion joints, etc. Thus, some of the main analyzes used to demonstrate the effectiveness of the use of HDPE geocells filled with concrete for lining channels will be presented, as: resistance to extraction with cell confinement, shear stress, surface abrasion, stability due to under pressure and excessive deformations. Finally, the main benefits that these structures present in relation to conventional ones are listed, and a comparison addressing productivity, installation and costs, sustaining their success through executed cases, as well as successful cases applied to different requests in Latin America.
Large scale trial evaluation of granular layers reinforced with geocells
Authors: Ibáñez Pérez Maria Carolina , Pires de Albuquerque Michelle
Published: September 2024

Geocells are three-dimensional geosynthetics made up of interconnected cells that confine the granular materials embedded in them. This confinement generates an increase in the rigidity and a decrease in the deformability of the reinforced layer, allowing for better performance of the pavement and optimization of non-renewable stone materials in transport infrastructure reinforcement applications. This study presents a full-scale test that consisted in the construction of a full-scale field with the aim of evaluating the behavior of granular materials with and without geocell reinforcement in transportation infrastructure. The experimental full-scale field is made up of five sections, the structure of this unpaved road consists of two layers of granular subbase material reinforced with two different geocells located at different depths, these layers are built on a clayey subgrade of low capacity. Material characterization tests were carried out and the subgrade and granular layers were subjected to measurements with the Benkelman Beam. Results from field measurements indicate that geocell reinforcement can reduce deflections at the top of granular layers and the MIF (Modulus Improvement Factor) can be calculated for the different geocells. The test results indicate that inclusion of geocell reinforcement significantly improves the rutting resistance and stability of reinforced test sections compared to the unreinforced test section.
Flexural behaviour of concrete beams reinforced with fiberglass geogrid
Authors: Shokr Mohamed , Meguid Mohamed , Bhat Sam , Malomo Deniele
Published: September 2024

In cold regions, especially within Canada, the degradation of non-structural concrete components in challenging environmental conditions has become a pressing issue. Traditional steel reinforcements are known to be susceptible to corrosion. With anticipated climate shifts causing variations in temperature, precipitation, and freeze-thaw cycles, there's an increasing need for more resilient reinforcement materials to deter premature cracking in non-structural concrete components. This study delves into the advantages of using low-ductility fibreglass geogrids as reinforcement layers to curb crack development and augment the flexural performance of plain concrete beams. Tests were carried out on nine concrete beams, each measuring 550×150×150 mm, with diverse reinforcement setups. The emphasis was on evaluating load-deflection characteristics, energy absorption capabilities, and modes of failure. Results suggest that lowductility fibreglass geogrid reinforcement markedly enhances the flexural strength of plain concrete, outperforming control beams. Additionally, fibreglass reinforcement showcases enhanced crack resistance and postcracking behaviour than plain beams. A Finite Element Analysis (FEA) was also executed using the Abaqus software, and its accuracy was confirmed through experimental data comparisons, yielding numerical figures for midspan deflection and peak load. This research furnishes pivotal insights into the prospective use of progressive reinforcement materials to combat environmental challenges in colder climates.
The use of geosynthetics for a “Green Desert” in Expo 2023 Doha, Qatar
Authors: Mottadelli Luca , Jayakrishnan P.V. , Mandavkar Sachin
Published: September 2024

Expo 2023 is an International Horticultural Expo to be hosted by Doha, Qatar, for a period of 6 months between 2023 and 2024. Spanning across 1.7 million square meters, the event takes place in the scenic ‘Al Bidda’ park in Doha. The ‘Expo House’ building is planned as a key attraction within the ‘Al Bidda’ park as part of this exposition. The theme of EXPO 2023 is “Green Desert, Better Environment”, with an aim to encourage, inspire, and educate people about cutting-edge methods to lessen desertification, and this aim is clearly reflected in the design of the ‘Expo House’ building. The Expo House is designed in the shape of a semicircle, with a vast open space in front and a fountain as a centerpiece. The benches along the sides of the pavilion form a natural amphitheater, offering stunning views and a perfect spot for the expo’s events and gatherings. One of the challenges was to adopt the right solution that performs the functions of soil retention, stabilization, plantation, and smart irrigation needs of the project. Maccaferri Middle East was chosen as the technology provider for the GREEN COVER SYSTEM; thanks to the wide range of geosynthetic products in our portfolio that can achieve the varying slope requirements of the artificial green mount in the project.
Experiences of mine closure cover with geosynthetics in Peru
Authors: Lagos Rainer , Fierro Gustavo
Published: September 2024

Peru is internationally recognized as one of the countries with significant mining reserves. According to the Department of Energy and Mines (MINEM), as of December 2021, a total of 672 mining concession holders were registered and declared in the Monthly Statistical Declaration (ESTAMIN). Likewise, 44 mining concessions are in the closure stage (progressive, post-closure and final). In addition, Peru has 7956 Mining Environmental Liabilities (MEL) as of 2020, according to the inventory approved by the Department of Energy and Mines, which need to be remediated as they constitute a permanent and potential risk to the health of the population, the surrounding ecosystem and property. As part of the closure of these MEL and closure of some mining components, the use of geosynthetics has increased in Peru, and we speak specifically of the closure cover in slopes, platforms, sidewalks and others, which has become relevant as an alternative solution for soils selected as part of a traditional closure, the objective of this work is to present a series of experiences of the application of geosynthetics in mine closure covers, which intervene in the physical, geochemical and hydrological stability. It is worth mentioning that geosynthetics have been applied in Peru for more than 30 years in mining projects.
Flyover reinforced soil and slope stabilization: Cases in Costa Rica
Authors: Bermúdez Campos Oldemar
Published: September 2024

A reinforced soil structure is the introduction of traction resistant elements to increase the resistance of the soil and decrease the deformation of the solid, improving the structural behavior. In the other hand, gabions are a well known system use from many years ago to solve problems due to slope stability by building gravity structures. The construction of public and private projects proposes great engineering challenges. We will see two specific cases in each area, in the private case the construction of a reinforced soil wall to generate a work platform where water tanks will be installed to supply a housing and hotel complex in the coastal area. For this situation, a retention work was designed and built using the Maccaferri Terramesh System, additionally reinforced with high-resistance Paragrid geogrids, manufactured by Linear Composites. The second case was developed in the public sector, corresponds to an overpass or upper road interchange, on Route 32 that connects the city of San José with the province of Limón in Costa Rica, where a reinforced soil wall was built for a major road junction on the new highway. This highway is very important to get the goods to the port of Moín, which is the main point of entry and exit of products from the country.
Geomembrane sustainability through longevity – 40 years of continuous service
Authors: Shehane Bill , Wilson Felon R.
Published: September 2024

Longevity is a key component of sustainability in geomembrane systems. This paper demonstrates that long geomembrane performance is possible with attention to product design when used in a properly designed containment facility. The example given is the geomembrane lined wastewater impoundments at Mammoth Cave National Park, which is a UNESCO World Heritage Site and International Biosphere Reserve. Installed in 1984, the liners are still in service. Exposed slopes and simple panel installation layout have provided low maintenance, without resource-consuming replacement or major repairs. The geomembrane installation along with results of 2016 geomembrane testing are presented, reviewed and discussed. Sustainability through longevity is discussed relative to geomembrane performance.
Integration of geosynthetics in reclaiming an oil sands tailings pond
Authors: Zhang Ying , Aboudiab Assile , Abusaid Ayman H. , Pollock Gordon W. , Uffen Derek
Published: September 2024

Global mining operations produce significant amounts of soil waste referred to as tailings. In oil sands mining, a portion of the deposited tailings is extremely soft and is primarily in a fluid state with solid contents (by weight) ranging between 30% and 40%. As part of reclaiming its Pond 5 oil sands tailings pond, Suncor constructed an engineered “floating” cover on top of the soft tailings deposits between 2010 and 2017 over an area spanning approximately 200 hectares to provide trafficability for limited construction equipment. This initial cover consisted of two layers of geosynthetics overlain by 2 m of petroleum coke. After construction of the initial cover, Vertical Strip Drains (VSDs) were installed through the majority of the capped area to enhance the consolidation rate of the underlying soft tailings. Additional coke has been placed on top of the initial coke cover to a total thickness of 4 m to 6 m. Previous publications have discussed the cover design, installation details of the geosynthetics, installation and performance of the VSDs, and performance of the cover. This paper presents the geosynthetics design, inspection of the geosynthetics post cover construction, and an update on the performance of the coke cover.
Repeated load triaxial tests of WickGrid™ stabilized base materials
Authors: Liu Jiming , Lin Cheng , Liu Minghao , Bhat Sam
Published: September 2024

In road construction, geogrids are frequently used to stabilize the base course through their lateral confinement applied to the base materials. Wicking fabrics are also used to improve road performance by installing them at the road base and subgrade interface to remove water from the road and reduce the build-up of pore water pressure while providing a separate function to mitigate the weak subgrade intrusion into the base course. However, the combined use of these two materials on the road has not been reported. This study aims to investigate the effectiveness of using an innovative geosynthetic composite called WickGrid™ in stabilizing the base materials. WickGrid™ is made by high stiffness biaxial polypropylene (PP) geogrid, heat bonded to a continuous filament nonwoven geotextile having wicking properties. To achieve the objectives, repeated load triaxial tests were conducted on sand materials to evaluate the improvement of the base materials in accordance with the AASHTO T 307-99(2021). The specimens were stabilized with WickGrid™ placed at the mid-height of the specimens. Meanwhile, unstabilized specimens and specimens stabilized with biaxial geogrids were also tested for comparison. The outcomes of these tests would allow for quantifying the beneficial effects of WickGrid™ on the improvement of road bases.
Bituminous geomembranes in mining applications in the Americas
Authors: Daly Natalie , Aguirre Ted , Escobar Emilio , Breul Bertrand
Published: September 2024

Bituminous geomembranes (BGM) have been used over the last 20 years in mining applications in innovative ways, to reduce the hazards of mining in the environment. BGM is a reinforced geomembrane made of a geotextile from 250 gr/m² to 400 gr/m2 impregnated by elastomeric bitumen. This gives the geomembrane unique features that enables their use in demanding weather conditions of low temperatures (– 45°C or -49°F in Northern Canada or Europe) or high temperatures (+40°C in Brazil) due to its low thermal expansion coefficient that avoids the formation of wrinkles. This allows the installation and welding at high temperatures in the countries of Latin America. This paper will describe how several unique characteristics have been used for challenging and environmentally sensitive mining projects throughout the Americas, including treatment of solid waste spoil dumps (heap leach pads, closure, and encapsulation of mining facilities) of different types of ore: gold, diamonds, lithium, copper, silver, rare earth: niobium and in hydraulic applications for tailings or clear water dams and reservoirs.
Innovative polymer application using geotextile dewatering bags
Authors: Snell Eddie
Published: September 2024

Geotextile dewatering bags have been a construction industry standard for several decades. Erosion control supply companies often recommend them as a solution to achieve clean water for discharge compliance on project sites. The bags are effective at containing coarse sediments from pumping activities. They are not very effective at capturing fine particulate matter and often require additional measures to produce clean water that meets compliance limits for stormwater discharge activities. The inclusion of polymers in the dewatering process can effectively treat the fine particulate matter and produce very clean discharged water. Standard practices have introduced the polymer into the bag during pumping activities. The idea is that the polymer will react with the sediment laden water and be retained in the bag. Unfortunately, this often results in the bag becoming severely clogged. This restricts pumping flow rates and accelerates containment failure of the geotextile bag. Contractors must then use many more bags at a reduced flow rate to treat the needed water volume. An alternative method for polymer application is to introduce it after passing through the geotextile bag. The bag is then used as a pre-filter and a way to convert concentrated flow into sheet flow. A simple containment is built around the dewatering bag and is used to direct the water flow over polymer blocks for treatment. This treatment consists of a soil-matched polymer (optimal results), mixing area with contact time, and a particle capture area to remove polymer treated sediment.
Lifetime considerations of geotextile UV exposure before installation
Authors: Beaumier David , Fourmont Stephan , Koerner George
Published: September 2024

Geotextile are in most case intended for buried application, without exposure to sunlight. However, a short exposure to sunlight may occur before installation. Because of potential delay of installation and soil burying, the material is required to meet UV resistance. Artificial UV weathering will assess the potential risk of unintended exposure to sunlight. Photodegradation reactions consider the interactions with exposure conditions as well as polymer sensitivity to sunlight. Based on both laboratory measurements and field data, this paper evaluates the effect of light intensity, temperature and humidity with climates. Using polymer relation of its UV light sensitivity with the effective irradiance, a cumulative index is calculated for the reduction of geotextile service life from exposure to sunlight. Artificial weathering cycles for geotextiles are compared and related to the specific degradation mechanisms of polypropylene and polyethylene terephthalate. The reaction rate is correlated with temperature, respectively for each polymer. A model using radiant energy and temperature is proposed for guidance to service life prediction of partly UV-exposed geotextiles.
Bender element sensor technology to quantify local stiffness enhancement of geogrid-stabilized aggregate specimens
Authors: Wang Han , Kang Mingu , Kim Youngdae , Qamhia Issam I. A. , Tutumluer Erol , Shoup Heather
Published: September 2024

Geogrids improve pavement performance and extend lifespan by making the unbound aggregate base/subbase course stiffer. Extruded (i.e., punched and drawn) geogrids are widely used in pavement applications. This paper presents an experimental evaluation of multi-axial extruded geogrids with various aperture shapes for pavement applications. The study quantified modulus enhancement ratio and identified the extent of the geogrid-stiffened zone. Two types of aggregates (i.e., crushed limestone and partially crushed gravel), commonly used in Illinois for base or subbase course, were utilized. Repeated load triaxial tests were conducted on 6-in. diameter and 12-in. height cylindrical specimens instrumented with embedded shear wave transducers in the form of Bender Element (BE) sensors. The BE pairs were horizontally placed at three different heights above the geogrid. Resilient moduli of the aggregate samples were determined following the AASHTO T 307 standard test procedure. Concurrently, the localized small-strain moduli at different heights above the midheight of the specimen were determined from the shear wave velocities computed according to the first arrival times from the BE sensors recorded at the end of the application of each stress state. The results reveal that resilient modulus tests do not capture the geogrid effects, while BE sensors can quantify the local stiffness enhancement due to a geogrid, and the extent of the geogrid-stiffened zone. Results show that the multi-axial geogrids provided a 45% increase in small strain modulus for both aggregate types in the vicinity of the geogrid.
Resistance and durability of high strength geotextile bags for hydraulic works
Authors: Fierro Gustavo
Published: September 2024

There is a need to build hydraulic works for riverside protection in case of flood as well as a mitigation project for high scour in places where rock material is very expensive or does not exist, therefore hard armour rock, rip rap or even concrete are unattractive alternatives. In several countries of the world, geotextile bags of high resistance have been used to achieve a valid and economical alternative. Themes related to stability of structures with bags that are very important have been dimensioned by some researchers, but there is still no information on how to relate the mechanical characteristics of the components of the bags with their manufacturing and also its service behaviour. This research offers details to be able to know the mechanical characteristics of thread types, geotextile and seaming according to the infill material type to be used to have an equivalent of a rock with the use of high resistance geotextile bags. This is also oriented to know its durability before abrasion, impact and UV radiation. Tests carried out in our laboratories are included as well as those carried out by other researchers both oriented to a methodology that provides an appropriate dimensioning of this type of structures. Some experiences where this methodology was used will be also included as well as the appropriate references.
Numerical investigation of the interaction of back-to-back MSE walls
Authors: Li Fuxiu , Zheng Yewei
Published: September 2024

The behaviour of back-to-back MSE walls is significantly influenced by the geometry, especially for the horizontal distance (D) between the back of the reinforced soil zone of the two MSE walls or the width-to-height ratio (RWH) of the system. In the Federal Highway Administration (FHWA) design guidelines [1] (Berg et al. 2009), two cases are considered based on the horizontal distance of the two MSE walls. However, no justification is provided for this assumption. Therefore, research is needed to investigate the interaction of back-to-back MSE walls with different horizontal distances. In addition, previous studies generally indicate that ignoring the interaction effect between the back-to-back MSE walls would result in overestimation for the design; however, no quantitative evaluation is provided regarding the interaction of back-to-back MSE walls [2-4]. This paper presents a numerical study of the interaction analysis of the static behaviour of back-to-back MSE walls. A parametric study is conducted to investigate the effect of horizontal distance (width-to-height ratio) on lateral soil thrust and required tensile strength. Results from this investigation provide insights on the interaction of back-to-back MSE walls.
Experimental study on a new type of FBG-3D printed geogrid in embankment reinforcement
Authors: Zhang Mengxi , Zhu Hao
Published: September 2024

Fiber Bragg Grating (FBG) has been widely used in many civil engineering applications to sense strains and deformations. Combining the advantages of geosynthetics and FBG, this paper creatively presents a new type of FBG-3D printed geogrid, which allows reinforcement and accurate deformation monitoring. Geogrid is directly used as the packaging structure of FBG sensor, and the complete coordinated deformation between the grating monitoring areas of FBG sensor and geogrid is obtained through calibration test. A series of model tests were carried out with FBG-3D printed geogrid to study the influence of reinforcement layers and reinforcement spacing on the bearing capacity and deformation of embankment under cyclic loading. The test results showed that geogrid effectively improved the footing settlement, slope displacement of reinforced embankment under cyclic load, and the effect was more obvious with the decrease of geogrid spacing. The strain data inside the embankment was accurately collected by FBG sensors. Relevant research provides valuable suggestions for the development and application of new geosynthetics.
Reinforcement of piling platforms with geogrids over dewatered docks with very soft soils: Wood Wharf, London
Authors: Guerra-Escobar Patricia , Bernardini Pablo , Saeed Rozhan
Published: September 2024

Wood Wharf is a major redevelopment of 23 acres designed to provide residential and office buildings as well as public spaces for shops, restaurants, parks and community uses. The development is located on the Isle of Dogs, Canary Wharf, London. This paper describes the design and results of the piling mats required to construct the buildings in the area of the South Dock, where 14,000m2 of land had to be reclaimed. Cofferdams were installed to create a watertight retaining structure to facilitate dry construction methods in the reclaimed area behind the new quay wall. To construct the different buildings, CFA and LDA piles between 8m to 34m deep were installed for the foundations. The soil profile primarily comprised Made Ground, Dock Sediments and River Terrace Deposits with very low undrained shear strengths between 2.5 to 42 kPa. The rigs to be used on site were 225 tons with applied pressures in the range of 300 to 470kPa and loadings of more than 1500kN. A series of reinforced piling mats were required to support the heavy rigs and reduce the applied pressures over the foundation soil. The design of the working platforms reinforced with geogrids was conducted in two stages, first to improve the modulus of the platform using recycled granular material, and second to provide safe platforms to support the heavy rigs.
Bearing capacity of strip footings seated on unreinforced and reinforced granular layers over random homogeneous and isotropic spatially variable undrained soft clay
Authors: Bathurst Richard J. , Chenari Reza Jamshidi
Published: September 2024

The bearing capacity of a footing seated directly on a soft clay foundation with constant undrained shear strength is the classical Prandtl geotechnical problem. However, a footing seated directly on an undrained clay soil is an unlikely arrangement in practice. Rather, a granular layer is used as a working platform for the construction of the footing and to dissipate the footing loads over a wider area of the clay foundation surface. This paper revisits the footing problem for the case of a footing seated directly on the clay foundation, and seated on an unreinforced and geosynthetic reinforced granular layer overlying the clay foundation. Both deterministic and stochastic numerical modelling of the bearing capacity problem using the program FLAC 2D were carried out. The relationship between the design factor of safety and probabilistic margins of safety is explored for clay foundations with random homogenous and isotropic spatially variable undrained shear strength with mean strengths from 5 to 25 kPa (very soft to soft clay). For practical target probabilistic margins of safety against exceeding a design bearing capacity, the random homogenous soil condition is shown to be the most critical case for design.
Life cycle costs and mid-term performance of a geogrid-stabilized pavement section, an economical and sustainable approach, case study, RN-39 Honduras
Authors: Castro Javier , Galindo Alex
Published: September 2024

When we talk about mechanical stabilization of granular layers with geogrids in roadway applications, we often mention that these pavements have a better performance along the time and a reduced cost along the whole life cycle. In the last years we have been measuring the International Roughness Index (IRI) of a segment of multi-axial with triangular aperture geogrid-stabilized road of 45.6 km of length and comparing it with a non-stabilized segment of 30.7 km of length, which was constructed in the same period and was commissioned the same year, for the same traffic. In terms of deterioration based on the International Roughness Index (IRI) for each segment, the mechanically stabilized road has shown a better performance than the non-stabilized segment, this publication seeks to show the tendency of the IRI curve for both sections, and the differences in their behavior. In addition, an analysis with the software; Highway Development and Management, version 2.0 (HDM-4) will be conducted to estimate the impact in the road user’s costs which are part of the life cycle cost and compare both sections, as well as an attempt to emulate and calibrate the IRI curve for the stabilized road section. This publication will help pavement engineers, designers, asset managers, highway engineers, departments of transportation and any people involved on roads, to better understand the economic advantages and performance benefits of mechanically stabilized granular layers with multi-axial geogrids on pavements and how they can help building resilient, durable, and sustainable road infrastructures.
Implementation of a Standardized Protocol for Postpartum Anemia: A Prospective Cohort Study
Authors: Lower Casey A. , Gleason Emily G. , Toda Asaki , Srinivas Sindhu K. , Levine Lisa D. , Power Maggie E. , Hamm Rebecca F.
Published: September 2024

Objective Implementation of standardized protocols for antepartum anemia increases intravenous iron (IVFe) use and improves predelivery hemoglobin (Hb). However, this condition is often overlooked and inadequately treated in postpartum care settings. We aimed to determine if implementation of a standardized protocol for postpartum anemia increases postpartum IVFe use and affects clinical outcomes.

Study Design We performed a prospective cohort study evaluating implementation of a standardized inpatient protocol for postpartum anemia. This protocol, implemented in December 2021, recommends (1) IVFe for postpartum Hb 7.0 to 8.9 g/dL and (2) oral iron for postpartum Hb 9.0 to 9.9 g/dL. We compared all postpartum inpatients at a single site from April 2021 (preimplementation period [PRE]) to April 2022 (postimplementation period [POST]). The primary outcome was any IVFe use. Secondary outcomes included number of IVFe doses, oral iron supplementation at discharge, postpartum complications, and length of stay.

Results A total of 805 patients were included (PRE = 401; POST = 404). Patients in the PRE and POST groups differed in ethnicity (PRE: 8.2% Hispanic vs. POST: 14.9% Hispanic, p = 0.003). IVFe use significantly increased from PRE to POST (PRE: 6.0% vs. POST: 11.1%, p = 0.009) even when controlling for differences between groups (adjusted odds ratio: 2.48, 95% confidence interval: [1.08–5.67]). Patients receiving IVFe in the POST group were more likely to receive the recommended three doses of IVFe compared with patients receiving IVFe in the PRE group (POST: 29% vs. PRE: 4%, p = 0.04). Patients in the POST group had shorter lengths of stay than in the PRE group (POST: 1.69 days vs. PRE: 1.81 days, p < 0.001). There were no significant differences in blood transfusion, oral iron supplementation, or postpartum complications.

Conclusion Implementation of a standardized protocol for postpartum anemia increased IVFe use without increasing length of stay.

Key Points
Not Just CTEPH: A Narrative Review on the Spectrum Approach to Postpulmonary Embolism Conditions
Authors: Biondi Filippo , Alberti Mattia , Montemaggi Elisa , D'Alleva Alberto , Madonna Rosalinda
Published: September 2024

Three mutually exclusive entities can underlie a postpulmonary embolism syndrome (PPES): not obstructed postpulmonary embolism syndrome (post-PE dyspnea), chronic thromboembolic pulmonary disease (CTEPD), and chronic thromboembolic pulmonary hypertension (CTEPH). Cardiorespiratory impairment in CTEPH and CTEPD underlies respiratory and hemodynamic mechanisms, either at rest or at exercise. Gas exchange is affected by the space effect, the increased blood velocity, and, possibly, intracardiac right to left shunts. As for hemodynamic effects, after a period of compensation, the right ventricle dilates and fails, which results in retrograde and anterograde right heart failure. Little is known on the pathophysiology of post-PE dyspnea, which has been reported in highly comorbid with lung and heart diseases, so that a “two-hit” hypothesis can be put forward: it might be caused by the acute myocardial damage caused by pulmonary embolism in the context of preexisting cardiac and/or respiratory diseases. More than one-third of PE survivors develops PPES, with only a small fraction (3–4%) represented by CTEPH. A value of ≈3% is a plausible estimate for the incidence of CTEPD. Growing evidence supports the role of CTEPD as a hemodynamic phenotype intermediate between post-PE dyspnea and CTEPH, but it still remains to be ascertained whether it constantly underlies exercise-induced pulmonary hypertension and if it is a precursor of CTEPH. Further research is needed to improve the understanding and the management of CTEPD and post-PE dyspnea.
Self-removing salt crystals
Authors: McBride Samantha
Published: September 2024

A newly discovered mechanism by which salt crystals leap off nanoengineered surfaces may lead to the development of industrial materials that resist the buildup of minerals from fresh and salt water.
Nanoscale dynamics of the cadherin–catenin complex bound to vinculin revealed by neutron spin echo spectroscopy
Authors: Callaway David J. E. , Nicholl Iain D. , Shi Bright , Reyes Gilbert , Farago Bela , Bu Zimei
Published: September 2024

We report a neutron spin echo (NSE) study of the nanoscale dynamics of the cell–cell adhesion cadherin–catenin complex bound to vinculin. Our measurements and theoretical physics analyses of the NSE data reveal that the dynamics of full-length α-catenin, β-catenin, and vinculin residing in the cadherin–catenin–vinculin complex become activated, involving nanoscale motions in this complex. The cadherin–catenin complex is the central component of the cell–cell adherens junction (AJ) and is fundamental to embryogenesis, tissue wound healing, neuronal plasticity, cancer metastasis, and cardiovascular health and disease. A highly dynamic cadherin–catenin–vinculin complex provides the molecular dynamics basis for the flexibility and elasticity that are necessary for the AJs to function as force transducers. Our theoretical physics analysis provides a way to elucidate these driving nanoscale motions within the complex without requiring large-scale numerical simulations, providing insights not accessible by other techniques. We propose a three-way “motorman” entropic spring model for the dynamic cadherin–catenin–vinculin complex, which allows the complex to function as a flexible and elastic force transducer.
論上古漢語副詞的全稱量化與相關問題
Authors: Wei Pei-chuan
Published: September 2024

抽象的

本文主要是探討上古漢語副詞的全稱量化功能的問題。所涉及的副詞有「皆、咸、俱、盡、悉、具」等六個，其中較為深入探討的為「皆、俱、盡、悉、具」等五個。本文所探討的議題主要有三；一，這些副詞所約束的語法成分為何？二，這些副詞的性質與功能為何？三，這些副詞使用上的限制與其來源動詞間的關連為何？第二個議題是本文的中心議題，在這個議題上本文得到如下的結論：｢俱」不能算是具有全稱量化的功能。至於「皆、盡、悉、具」等雖然不能說沒有全稱量化的功能，但是這些副詞的全稱量化功能是次生的，是由這些副詞的主要功能或核心義衍生出來的。
Electromagnetic field in an expanding universe
Authors: Almuthaybiri Mona H , Arbab Arbab I
Published: September 2024

An expanding universe filled with a massive electromagnetic field is studied. The electromagnetic field (photon) is found to acquire mass during an inflationary period. The photon mass varies with the Hubble parameter as m

γ
= 3ℏ
H/c
2, where H, ℏ and c are the Hubble parameter, Planck constant, and speed of light. A leftover magnetic field since the inflationary era permeates the space between galaxies and interstellar media. The strength of the electromagnetic field changes with the scale factor, E ∝ a
−3. The photon gains mass when interacting with the gravitational field while remaining massless in flat space. The massive electromagnetic field adds energy density to the Universe proportional to m
2.
Diffusion coefficients preserving long-time correlations: consequences on the Einstein relation and on entanglement in a bosonic Bogoliubov system
Authors: Hamdouni Yamen
Published: September 2024

We analytically derive the diffusion coefficients that drive a system of N coupled harmonic oscillators to an equilibrium state exhibiting persistent correlations. It is shown that the main effect of the latter consists in a renormalization of the natural frequencies and the friction coefficients of the oscillators. We find that the Einstein relation may be satisfied at low temperatures with frequency-dependent effective friction coefficients provided that the physical constraints are fulfilled. We also investigate entanglement evolution in a bipartite bosonic Bogoliubov system initially prepared in a thermal squeezed state. It is found that, in contrast to what one may expect, strong coupling slows down sudden death of the entanglement, and for initially separable states entanglement generation may occur.
3D printing of liquid metal circuits on fabric for stretchable heater application
Authors: Dong Sihan , Wang Xincheng , He Pei , Yang Junliang
Published: September 2024

Liquid metals (LMs), due to their excellent stretchability, low resistance, and high thermal conductivity, has become an ideal material for preparing stretchable circuits. 3D printing technology can produce patterns with complex structures with high precision and is suitable for low-cost large-scale production of circuits. However, the high surface tension of liquid metals limits the practical application of 3D printing of LMs. In this work, we proposed a method for preparing a mixed ink based on thermoplastic polyurethane, Cyrene solvent, and LMs, and producing stretchable LMs-based electrodes through 3D printing on a fabric substrate. The stretchable LMs-based electrode prepared by this method shows a wide range of strain response and excellent tensile recovery performance, providing theoretical guidance for the application of LMs electrodes. In addition, the LMs-based heaters showed good Joule thermal response at low voltages, as well as good tensile stability, providing a new strategy for wearable heaters.
A Vortex Electromagnetic Wave Beam Control Method based on Amplitude-Modulated Concentric Circular Array
Authors: Sun Jiayue , Chen Qian , Fu Chaowei , Liu Junhao , Zheng Chengxin
Published: September 2024

In order to enhance the design efficiency of vortex electromagnetic (EM) wave radar detection systems, a method for generating and controlling vortex EM waves based on amplitude-modulated concentric circular array (CCA) is proposed. This method allows for precise control of the vortex EM waves, ensuring accurate main lobe direction while effectively reducing sidelobes. Based on approximate orthogonal transformation, formulas for calculating the excitation amplitudes of each sub-circular array are derived and the time complexity of this method is negligible compared to search-based algorithms. Extensive simulation experiments are conducted and compared with the results obtained from the genetic algorithm (GA) approach, providing robust evidence of the effectiveness of this method(SLL < -30dB).
Study of Life Feed in Cantang Grouper Hatcheries (Epinephelus fuscoguttatus x Epinephelus lanceolatus)
Authors: Meilina Sinta Cahya , Al Ma’rifah Nazhariyyatu , Rachmawati Hanna Aulia , Sari Luthfiana Aprilianita , Sari Putri Desi Wulan , Nindarwi Daruti Dinda , Arsad Sulastri
Published: September 2024

Cantang grouper (Epinephelus fuscoguttatus x Epinephelus lanceolatus) is a cross between female tiger grouper (Epinephelus lanceolatus) and male tiger grouper (Epinephelus fuscoguttatus), according to statistical data from the Ministry of Maritime Affairs and Fisheries (KKP) it has a production value of 4,406 tons in 2022 and experienced an increase in growth of 33.92%. Fulfilling this need can be done by maximizing the hatchery process, the key to which is natural food, namely for broodstock (flying fish, tuna and squid) and larvae (chlorella, artemia, rotifers, rebon shrimp). The aim of this article is to study natural feed in the hatchery of cantang grouper (Epinephelus fuscoguttatus x Epinephelus lanceolatus). This study was conducted at the Pecaron Brackish Water Aquaculture Fisheries Center (BPBAP), Situbondo, East Java on 19 June - 19 August 2023. The work method used was a descriptive method with primary and secondary data collection. The study results showed that the Hatching Rate (HR) was 73.25%, the Survival Rate (SR) was 15.98%, the Specific Grow Rate (SGR) was 0.24 g/day. Water quality measured is temperature ranging from 28-30°C, pH between 7.78-8.44, salinity between 31-32 ppt, dissolved oxygen (DO) between 5.72-6.20 mg/L, ammonia between 0.001-0.031 mg/L, nitrite is 0.001 mg/L. Natural feed has complete amino acids, fatty acids, enzymes and minerals which function in the maturation of the parent gonads and larval growth.
Behaviour of wet clay due to off-road traffic loading
Authors: Swamy V S , Pandit R , Yerro A , Sandu C , Castellanos B , Rizzo D , Sebeck K
Published: September 2024

The presence of water in the soil can greatly affect the trafficability of off-roading vehicles, making it difficult to operate. As the water content increases, it can eventually lead to sinkage and immobility. Despite the relevance of this topic in many applications, such as military, agricultural, and earthmoving vehicles, the studies available on tire and moist soil interaction are limited. The numerical modeling of such a system is very challenging because it requires accounting for hydro-mechanical effects, large deformations, non-linear behavior, and complex interactions between the tire and the soil. This work contributes to the understanding of the behavior of moist clay under the influence of traffic loading. In particular, the preliminary results of numeric simulations to study the interaction between moist clay and a passing tire using physics-based techniques are presented. A great emphasis is given to the development of an accurate soil model that can capture the fundamental characteristics of moist clays in saturated conditions.
Virtual Development of a Challenger type, single-seater vehicle for the World Solar Challenge Competition
Authors: Roman B , Croitorescu V
Published: September 2024

The paper presents the evaluation of the feasibility of a single-seat solar prototype vehicle for the World Solar Challenge competition, by estimating its autonomy. The research carried out contains several stages of study, including the development of mathematical models that are intended to be accurate enough to provide realistic predictions on the functional behaviour of the battery pack, so that it can be determined whether the designed vehicle will be able to complete the stages of the proposed competition. The paper also presents the CFD modeling approach, and the results obtained after simulating different body shapes advancements. In addition, the functional modeling approach is presented to evaluate the vehicle battery range, including the possibility to use different designs and types for the battery pack and to verify if the designed vehicle can achieve the race finish line.
Experimental and numerical analyses on the modal behaviour of an aluminium alloy sheet
Authors: Moisescu A R , Anghelache G
Published: September 2024

The study of modal behaviour for vehicle body panels represents a field of interest for automotive engineering, having a major influence on automotive comfort, with respect to vehicle noise, vibration and harshness, but also concerning the durability of vehicle body. The investigation of natural frequencies and vibration mode shapes is crucial in the design phase, because essential information can be obtained concerning the behaviour of the components in dynamic conditions. The current paper focuses on the investigation of vibration modes and frequency response function on an aluminium alloy sheet. The aim of the paper is to perform the study of modal behaviour both experimentally and theoretically, through measurements using the impact hammer method and respectively through finite element analysis. The CAD model of the aluminium alloy sheet has been developed in Catia V5 environment in view of elaborating the finite element model, which has been used for investigation of modal behaviour, taking into account the case of free vibrations. Through the modal finite element analysis performed in Ansys Workbench, the natural frequencies of the aluminium alloy sheet, as well as the corresponding mode shapes have been obtained. Experiments have been performed on an aluminium alloy sheet, mounted on an elastic support with low natural frequency. The impact hammer method has been used for obtaining the natural frequencies, through frequency analysis of accelerations measured with two piezoelectric accelerometers mounted on the aluminium alloy sheet. The frequency response function has been computed from the response acceleration measured on the aluminium alloy sheet and the impact force measured using the force transducer of the impact hammer. Virtual instruments have been developed in LabVIEW environment for data acquisition, time domain and frequency analysis, as well as for determining the frequency response function using the measured signals. The natural frequencies obtained from the finite element analyses have been compared to the results of measurements and very good similarities have been ascertained. The experimental investigation of modal behaviour contributed to the validation of the finite element model, but further research is required to investigate the possibilities of improving the modal behaviour of the aluminium alloy sheet.
Study concerning methods for managing used engine oil. Analysis of a questionnaire-based survey
Authors: Armioni D M , Ionel I , Raţiu S A
Published: September 2024

This paper focuses on methods of managing used engine oil by presenting an analysis of the results of a survey based on a questionnaire designed by the authors, which aims to illustrate the real, objective situation of the management of used engine oil generated by vehicles powered by internal combustion engines. The answers are analyzed for each question separately and both conclusions and implementable objectives that could improve the current situation are highlighted. In order to facilitate the understanding of the current framework, general aspects regarding the management of used engine oil are also presented, with an emphasis on the legislative perspective.
Diagnosing the truck engine operation by evaluating engine oil wear and issuing maintenance recommendations
Authors: Zaharia C , Niculescu R , Năstase M , Clenci A
Published: September 2024

The lubricating oil of an internal combustion engine (i.c.e.) performs several functions having a major contribution to the reliability of the system, implying proper operation during the period of exploitation. Replacing the engine oil ahead reaching the turnover / time corresponding to preventive maintenance it turns out to be sometime an imperative action, with negative implications on operating costs. Any user of today vehicles desire to use the engine performances at full percentage, and for that an important condition becomes the changing of the oil at defined intervals of time/rollover intervals. Thus, it is very important to be aware when to replace because a late change of oil can affect the engine operation and, surely, the performance of the vehicle. Premature oil change influences costs, the environment and is considered a harmful action in terms of the process of depletion of resources. As regards the operating conditions, it is intended that they are similar for all vehicles taken into consideration. It is imperative that the study be carried out by investigating the operation of a single type of engine, with a single type of engine oil, for several vehicles with the same technical characteristics. It is considered that the transport fleets are the concrete source that falls under the already mentioned conditions and a methodology based on the analysis of the 10W30 oil samples used in the MX - 11 330 H2, EURO 6 engines of the DAF vehicles within the fleet of one transport company from Argeş county will be used. The authors of this paper will analyze the following properties of the oil: viscosity, density, flash point, contamination with fuel and water content, these being the most important in illustrating the degree of wear and tear of it. The information about the evolution during the exploitation period of these characteristics is the basis for the elaboration of maintenance strategies considering the three desiderata: the environmental issues, the vehicle’s reliability, and the operating costs of the vehicle.