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Left ventricular noncompaction cardiomyopathy is associated with heart failure, arrhythmia, and sudden cardiac death. The developmental mechanism underpinning noncompaction in the adult heart is still not fully understood, with lack of trabeculae compaction, hypertrabeculation, and loss of proliferation cited as possible causes. To study this, we utilised a mouse model of aberrant Rho kinase (ROCK) signalling in cardiomyocytes, which led to a noncompaction phenotype during embryogenesis, and monitored how this progressed after birth and into adulthood. The cause of the early noncompaction at E15.5 was attributed to a decrease in proliferation in the developing ventricular wall. By E18.5, the phenotype became patchy, with regions of noncompaction interspersed with thick compacted areas of ventricular wall. To study how this altered myoarchitecture of the heart influenced impulse propagation in the developing and adult heart, we used histology with immunohistochemistry for gap junction protein expression, optical mapping, and electrocardiography. At the prenatal stages, a clear reduction in left ventricular wall thickness, accompanied by abnormal conduction of the ectopically paced beat in that area, was observed in mutant hearts. This correlated with increased expression of connexin-40 and connexin-43 in noncompacted trabeculae. In postnatal stages, left ventricular noncompaction was resolved, but the right ventricular wall remained structurally abnormal through to adulthood with cardiomyocyte hypertrophy and retention of myocardial crypts. Thus, this is a novel model of self-correcting embryonic hypertrabeculation cardiomyopathy, but it highlights that remodelling potential differs between the left and right ventricles. We conclude that disruption of ROCK signalling induces both morphological and electrophysiological changes that evolve over time, highlighting the link between myocyte proliferation and noncompaction phenotypes and electrophysiological differentiation. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) is incinerated to reduce the volume and recover energy and materials. The generation of MSW has been increasing over the past few decades due to the increase in population and changing consumption habits. Rising environmental and economic concerns have increased the importance of waste treatment and recovery. Currently, MSW may take three alternate or parallel routes: direct recycling, incineration, or landfill, depending on the country and location. MSW incineration has three products in addition to energy: bottom ash, fly ash, and off-gas. After incineration, bottom ash usually still contains many materials to be recovered, such as glass, ceramics, and metals with a degree of oxidation. This study focuses on aluminium recovery from MSW incineration bottom ash from two different countries. The 2–30 mm fraction of aluminium particles was characterized in terms of its size, shape, and oxide thickness, and its effects on aluminium recovery were investigated. In addition, the ability of mechanical pre-treatment to remove oxides prior to melting was studied. The results were compared with the analytical modeling developed in this study. An increasing particle size and surface area resulted in an increase in aluminium recovery. Mechanical pre-treatment increased the yield for smaller particles to a larger extent than larger particles due to the difference in the oxide/metal ratio. [ABSTRACT FROM AUTHOR]

Successful management of chalk reservoirs for various subsurface applications as well as construction in chalk/limestone formations rely on descriptions of compaction behaviour commonly predicted from laboratory experiments. This study aims to understand and describe better the compaction behaviour that oil and water-saturated chalk undergo. Seven North Sea Lower Cretaceous chalk samples with initial porosity ranging from 31 to 45% were compacted hydrostatically in the laboratory. The traditionally named elastic, transitional, elastoplastic and strain hardening phases were identified from stress–strain curves. The observed compaction behaviour is described in phenomenological terms based on the interpretation of Biot's coefficient as a measure of grain-to-grain contact area within the chalk frame. Biot's coefficient was derived from elastic wave velocities and bulk density via Gassmann fluid substitution by first approximations assuming a simple calcite-bearing rock frame. Biot's coefficient identifies both elastoplastic and elastic phases in the initial compaction phase traditionally denoted as the elastic phase. The plastic component of the elastoplastic phase presumably originates from closure of micro-crack introduced by unloading and equilibration from core recovery. Biot's coefficient is a reliable indicator of pore collapse, and a specific constant magnitude of purely elastic strain controls the onset of pore collapse. In situ reservoirs presumably only experience the elastic strain during effective stress changes, not the elastoplastic behaviour seen in experiments. Yet, as laboratory experiments often form a calibration background for large-scale models, quantifying the plastic component of elastoplastic phases and pore collapse from pure elastic strain provides new insight to improve models and avoid the unphysical use of porosity as a controlling physical parameter. Highlights: During initial compaction, both elastoplastic and elastic phases exit and are identified from Biot's coefficient. During compaction, a local minimum Biot's coefficient derive from ultrasonic velocities is a reliable indicator of pore collapse. A critical and purely elastic strain derived from applied stress and dynamic moduli is the controlling mechanism of pore collapse. Identification of subphases and a critical pore collapse elastic strain provides new insight into calibration of reservoir model from experiments. [ABSTRACT FROM AUTHOR]

While the 'compact city' can provide environmental benefits, densification can result in negative trade-offs at the local scale – e.g. through increases in density and the removal of urban green space – and densification projects are often rejected by locals. This paper explores examples of densification in a compact European city, integrating different stakeholder perspectives from planners as well as neighbours of densification projects. Neighbours do not reject densification per se, but evaluate the individual projects and their contexts. Evaluation depended mostly on how the projects impacted urban green space, social mix and available parking spaces. Implications are discussed and 'good practice' criteria that could reduce the trade-offs of densification are suggested. [ABSTRACT FROM AUTHOR]

Reservoir quality prediction in deeply buried reservoirs represents a complex challenge to geoscientists. In sandstones, reservoir quality is determined by the extent of compaction and cementation during burial. During compaction, porosity is lost through the rearrangement and fracture of rigid grains and the deformation of ductile grains. During cementation, porosity is predominantly lost through the growth of quartz cement, although carbonate and clay mineral growth can be locally important. The degree of quartz cementation is influenced by the surface area of quartz available for overgrowth nucleation and thermal history. Clay grain coats can significantly reduce the surface area of quartz available for overgrowth nucleation, preventing extensive cementation. Using a coupled-effect compaction and cementation model, we have forward-modelled porosity evolution of surface sediments from the modern Ravenglass Estuary under different maximum burial conditions, between 2000 and 5000 m depth, to aid the understanding of reservoir quality distribution in a marginal marine setting. Seven sand-dominated sub-depositional environments were subject to five burial models to assess porosity-preservation in sedimentary facies. Under relatively shallow burial conditions (<3000 m), modelled porosity is highest (34 to 36%) in medium to coarse-grained outer-estuary sediments due to moderate sorting and minimal fine-grained matrix material. Fine-grained tidal flat sediments (mixed flats) experience a higher degree of porosity loss due to elevated matrix volumes (20 to 31%). Sediments subjected to deep burial (>4000 m) experience a significant reduction in porosity due to extensive quartz cementation. Porosity is reduced to 1% in outer estuary sediments that lack grain-coating clays. However, in tidal flat sediments with continuous clay grain coats, porosity values of up to 30% are maintained due to quartz cement inhibition. The modelling approach powerfully emphasises the value of collecting quantitative data from modern analogue sedimentary environments to reveal how optimum reservoir quality is not always in the coarsest or cleanest clastic sediments. [ABSTRACT FROM AUTHOR]

Data-structure dynamization is a general approach for making static data structures dynamic. It is used extensively in geometric settings and in the guise of so-called merge (or compaction) policies in big-data databases such as LevelDB and Google Bigtable. Previous theoretical work is based on worst-case analyses for uniform inputs—insertions of one item at a time and non-varying read rate. In practice, merge policies must not only handle batch insertions and varying read/write ratios, they can take advantage of such non-uniformity to reduce cost on a per-input basis. To model this, we initiate the study of data-structure dynamization through the lens of competitive analysis via two new online set-cover problems. For each, the input is a sequence of disjoint sets of weighted items. The sets are revealed one at a time. The algorithm must respond to each with a set cover that covers all items revealed so far. It obtains the cover incrementally from the previous cover by adding one or more sets and optionally removing existing sets. For each new set the algorithm incurs build cost equal to the weight of the items in the set. In the first problem the objective is to minimize total build cost plus total query cost, where the algorithm incurs a query cost at each time \(t\) equal to the current cover size. In the second problem, the objective is to minimize the build cost while keeping the query cost from exceeding \(k\) (a given parameter) at any time. We give deterministic online algorithms for both variants, with competitive ratios of \(\Theta(\log^{*}n)\) and \(k\) , respectively. The latter ratio is optimal for the second variant. [ABSTRACT FROM AUTHOR]

Synthesis of highly porous ceramic materials for catalytic converters based on coarse-dispersed αAl2O3 using a combination of compaction and thermochemical synthesis with the participation of active ultrafine binders is carried out. Using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM), it is established that the morphology of the synthesized material simultaneously includes large pores between filler particles (dominant αAl2O3 phase) and submicron pores in transboundary regions that appeared during the processes of liquid-phase sintering and gas evolution. A significant amount of indialite (Mg2Al4Si5O18) and spinel (MgAl2O4) formed as a result of thermochemical synthesis on surfaces and in the gaps between coarse-dispersed particles is revealed. The dominant pore size (according to the volume of mercury intrusion) is from 20 to 60 μm (about 73%), as well as pores with size from 0.4 to 2 μm (about 6%).The average pore size is about 9 μm. Highly porous materials with these characteristics of the pore space can be effectively used after modification as catalytic converters for the dehydrogenation of alkyl aromatic hydrocarbons with large molecular sizes (about 400 nm) with a long mean free path on the order of ~3–4 μm. [ABSTRACT FROM AUTHOR]

Calender process is important to improve the mechanical and electrochemical properties of cathode materials. To explore pressure effect on structure and resistance of electrode powder, the morphology and surface area of lithium cobalt oxide (LCO) powder under different pressure are investigated. Meanwhile, the real‐time stress, density, and conductivity of LCO powder upon compaction are tested by a self‐made detection system. Moreover, the battery performance of LCO powder after compaction is compared in coin cells. This work elucidates the relationship between compaction density, powder resistance, and electrochemical performance of cathode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Flax reinforced composites are becoming popular in automotive and civil industries due to their green production and recycling, and for good specific strength. To manufacture composites, firstly a multi-layer of flax preforms undergo compressive pressure before resin impregnation that causes nesting, wherein, fibres of one layer fit into the adjacent layers. This debulking of the preforms under compression is an important feature that determines the fibre volume fraction of composites. In this study, four flax structures such as: nonwoven tapes, unidirectional fabric, hopsack fabric, and nonwoven tape with glass veils were investigated for compaction behaviour under pressures between 1 and 10 bars, in single and multi-layer states, in dry and wet states, under different loading cycles, and in different ply orientations (0°/0° and 0°/90°). Nesting has been calculated for single- and multi-layer stacks. It was observed that the nonwoven structures shown greater thickness reduction compared to woven structures. Nesting factor was found to be higher than 1 for the nonwoven structures under compaction, indicating lower nesting, compared to the woven structures. In terms of thickness under repeated compaction, the reduction was the highest during first compressions, compared to the 2nd and 3rd compressions, for all the structures. When wettability was examined, thickness reduction for wet plies was higher for all the structures, compared to the dry phase. Finally, a comparative study was shown to evaluate fibre volume fractions of the composites. [ABSTRACT FROM AUTHOR]

Translation abstract Dark discoloration in the lower wall area on exposed concrete surfaces – Interactions between formwork vibrations and concrete technologyThe use of exposed concrete construction represents an irreplaceable architectural design element, particularly for the creation of represented concrete buildings. Despite an increasing variety of design possibilities, such as with colored or textured elements, many planners and builders still prefer smooth and uniformly light‐colored exposed concrete surfaces created for using in‐situ concrete constructions. Despite significant and technical advancements, optical irregularities like dark discolorations, are repeatedly observed in the production of such exposed concrete components. These discolorations cannot be fully explained by existing scientific approaches and cannot be technically eliminated so far. As a part of a research project jointly conducted by the Institute of Building Material Science of Leibniz University of Hannover and the German Concrete and Construction Technology Association (Deutscher Beton‐ und Bautechnik‐Verein E. V.), the mechanisms leading to dark discolorations in lower wall areas of exposed concrete components were systematically investigated. In Particular, a direct influence of formwork vibrations in interaction with concrete technological properties was identified as a central factor for dark discolorations. The likelihood of such discolorations significantly increases when stiffening concrete (i. e. concrete whose age is approaching the initial setting time) are either directly or indirectly set into vibration by the formwork. A significant interaction was found between the timing of vibration initiation, the concrete technological properties and the vibration parameters (frequency and amplitude). [ABSTRACT FROM AUTHOR]

A method has been proposed to enhance the mechanical properties of hot-finished sintered steels, which consists of additional plastic deformation with a degree of deformation, at which the intracrystalline bonding of the material is preserved. The effect of ultrafine silicon nitride particles on the structural formation and properties of hot-finished sintered steels is analyzed. [ABSTRACT FROM AUTHOR]

Williams, H.F.L., 2024. Testing digital elevation model of difference (DoD) estimation of washover fan thickness, Matagorda Peninsula, Texas. Journal of Coastal Research, 40(5), 852–859. Charlotte (North Carolina), ISSN 0749-0208. Washover fans are a fundamental component of coastal sediment budgets. While fans can be relatively easily delineated on air photos to obtain fan area, measurement of fan thickness, which is required for volume estimation, is problematic. Field surveys can be conducted, but fieldwork can be labor-intensive, costly, and time-consuming and have access problems. This study used pre- and poststorm LIDAR digital elevation models (DEMs) to create a digital elevation model of difference (DoD), which was then used to estimate the mean thicknesses of 10 Hurricane Harvey washover fans on Matagorda Peninsula, Texas. The accuracy of the LIDAR-derived fan thicknesses was assessed by comparing the LIDAR results to fan mean thicknesses based on pits excavated into fans. Seven out of 10 LIDAR-based thicknesses underestimated pit-based thicknesses, suggesting the presence of systematic bias in the LIDAR-derived DEMs. Underestimation of fan thicknesses was in the range of 36% to 56%. The source of the suspected bias is uncertain; it is possible that compaction of marsh sediments by the washover fans lowered the fans and reduced their apparent thicknesses. It is concluded that pre- and post-storm LIDAR DEMs can be used to estimate washover fan thickness, but in areas of compactible substrates, such as coastal marshes, steps should be taken to identify, evaluate, and address potential bias in the DEM data. [ABSTRACT FROM AUTHOR]

This review describes in detail the morphological, cytoskeletal and gene expression events leading to the gene regulatory network bifurcation point of trophoblast and inner cell mass cells in a variety of mammalian preimplantation embryos. The interrelated processes of compaction and polarity establishment are discussed in terms of how they affect YAP/WWTR activity and the location and fate of cells. Comparisons between mouse, human, cattle, pig and rabbit embryos suggest a conserved role for YAP/WWTR signalling in trophoblast induction in eutherian animals though the mechanisms for, and timing of, YAP/WWTR activation differs among species. Downstream targets show further differences, with the trophoblast marker GATA3 being a direct target in all examined mammals, while CDX2-positive and SOX2-negative regulation varies. [Display omitted] • Onset of compaction relative to polarisation varies among mammalian embryos. • De novo polarisation in embryos transits from apical domain to apical ring stage. • Restriction of nuclear YAP correlates to apical ring stage and trophoblast specification. • Hippo/Lats signals regulate YAP activity in mammalian embryos but not exclusively. • Variations in YAP/TEAD regulation of trophoblast lineage factors CDX2 and GATA3. [ABSTRACT FROM AUTHOR]

The present study assessed soil preparation in terms of the advantages it provides in lowering the physical obstacles and their influence on soybean cultivation, with reference to its establishment, development and yield, apart from quantification of the energy demand for tractor performance. The experiments were performed in the field adopting the randomized block design with a two-factor scheme (6x2). Factor A included a variety of soil preparations performed during the off-season of the soybean crop. Sowing was accomplished using the same fertilizer deposition mechanism only, and the areas having no soil preparation done were sown using various other fertilizer deposition mechanisms from the seeder, namely: (A1) sowing without soil preparation (SSPS)+double disc in the seeder (DD); (A2) SSPS+turbo disc (DT); (A3) SSPS+furrowing rod (HS); (A4) plow harrow+DD; (A5) scarified+DD and (A6) subsoiled+DD. Soil preparations before sowing were done on days 52 and 98 days, respectively, during the first and second harvests. Factor B included two soybean cultivars, namely: (B1) Nidera 6601 and (B2) Brasmax Valente. No interaction was observed between the factors investigated. While the scarification+DD showed the need for higher fuel consumption, the results were increased productivity. For the seeder-linked mechanisms, the HS gives more extensive root development of the plants and grain yield. On the contrary, while DD and DT show the combination of the highest operational capacity and lower fuel usage, this is related to lower grain yield. [ABSTRACT FROM AUTHOR]

The demand for nondestructive testing techniques (NDTs) that can be implemented continuously and cost-effectively for large-scale study purposes is increasing. Ground penetrating radar (GPR) as an NDT method permits the estimation of pavement materials characteristics without disrupting the serviceability of the system. This research used typical pavement materials for constructing load-bearing layers (base and subbase) for the GPR laboratory tests. A 2 GHz GPR antenna was applied to execute the tests by changing three essential variables of the material: water content, compaction and clay content. Machine learning and interactive methods were innovatively utilised to model the collected data. As a result, a multivariate non-linear empirical function is proposed by the interactive procedure. Furthermore, the machine learning modelling (SVM method) with R2 of 0.91 indicates promising results to evaluate the pavement layers' properties. Machine learning can enhance the speed and accuracy of analysis when faced with multi-variables and extensive data. [ABSTRACT FROM AUTHOR]

Abstract The California bearing ratio (CBR) of a granular materials are influence by the soil particle distribution indices such as D10, D30, D50, and D60 and also the compaction properties such as the maximum dry density (MDD) and the optimum moisture content (OMC). For this reason, the particle packing and compactibility of the soil play a big role in the design and construction of subbases and landfills. In this research paper, experimental data entries have been collected reflecting the CBR behavior of granular soil used to construct landfill and subbase. The database was utilized in the ratio of 78–22% to predict the CBR behavior considering the artificial neural network (ANN), the evolutionary polynomial regression (EPR), the genetic programming (GP), Extreme Gradient Boosting (XGBoost), Random Forest (RF) and the response surface methodology (RSM) intelligent learning and symbolic abilities. The relative importance values for each input parameter were carried out, which indicated that the (CBR) value depends mainly on the average particle size (D30, 50 & 60). They showed a combined influence index of 66% of the considered parameters in the model exercise. This further shows the importance and structural influence of the particles within the D50 and D60 range in a granular material consistency in the design and construction purposes. Performance indices were also used to study the ability of the models. The ANN model showed the best performance with accuracy of 88%, then GP, EPR and RF with almost the same accuracies of 85% and lastly the XGBoost with accuracy of 81%. Also, the RSM produced an R2 of 0.9464 with a p-value of less than 0.0001. These values show that the ANN produced the decisive model with the superior performance indices in the forecast of CBR of granular material used as subbase and waste compacted earth liner material. The results further show that optimal performance of the CBR depended on D50 and D60 for the design of subgrade, subbase, and liner purposes and also during the performance monitoring phase of the constructed flexible pavement foundations and compacted earth liners.

Abstract The progressive increase in the rate of production of plastic bottles by the beverage and food industries in Nigeria has increased considerably over time, constituting large volume of waste generations from plastic waste bottles. Also, increasing demand for eco-friendly soil improvement materials and the growing desire to minimize waste generated daily, prompted the need for this study to look into ways to use such wastes and other sustainable materials in soil improvement. This study investigated the potential use of sisal fiber and plastic waste strips as partial replacement for cement to enhance the geotechnical characteristics of lateritic soils. Various laboratory experiments were conducted, encompassing specific gravity determination, grain size distribution, compaction assessment, Atterberg limit, unconfined compressive strength (UCS), and microscopic analysis. Sisal fiber and plastic waste strips were each varied at 0, 0.5, 1.0, 1.5, 2.0 and 2.5% while maintaining a constant 5% cement added to all the mix proportions. Results of investigation revealed an enhancement in plasticity of the soils with both treatment methods. Liquid limit shows a steady drop from 43% in its natural state to 42% and 41% at 1% sisal fiber and 1% plastic strips content respectively, while plasticity index showed a decline from 14.8% in its natural form to 12.69% and 10.8% at 2% sisal fiber and 1% plastic waste strips content respectively. Strength properties of the treated soil increased with increase in admixtures content. Microanalysis of the natural and optimally modified soils showed alteration in the fabric arrangement of the particles of soils. Based on the results of the study, optimally 1–1.5% sisal fiber/5%cement and 1–1.5% plastic waste strips/5%cement meaningfully improved the soil strength and can both be used as sub-base materials for light trafficked roads.

Expansive soils present substantial challenges in civil engineering because they undergo volume fluctuations with changes in water content, mainly affected by the clay mineral montmorillonite. Nanotechnology has rapidly and widely improved, finding applications across all engineering fields. This study focused on enhancing soil engineering performance using lime alone and the impact of varying quantities of nanosilica with lime in the soil, focusing on engineering parameters like Atterberg limits, maximum dry density, optimum moisture content, and unconfined compressive strength over curing periods of 7, 14, and 28 days. In this study, the basic properties of soil were initially determined. Then, lime was mixed with soil in different proportions of 2%, 4%, 6%, and 8% according to the dry weight of the soil. Based on strength criteria, soil mixed with 4% lime gives the best results. Keeping the lime content constant at 4%, nanosilica was added to the soil. These findings suggest modifications in the amended soil's plasticity, compaction characteristics, and strength with the minor addition of nanosilica to lime-mixed black cotton soil. The enhancement in strength of expansive soils relies on the amount of lime and nanosilica and the duration of curing. After conducting tests, it was found that the optimal quantities for lime and nanosilica through strength performance tests are 4% and 3%, respectively. The research asserts that adding nanosilica to lime notably improves the mechanical properties of black cotton soil. Scanning electron microscopy and X-ray diffractometer analyses support these findings, revealing variations in the character and strength of the CSH phase over curing time. These conclusions offer wide-ranging relevance for projects seeking to enhance the engineering properties of soft soils. Practical Applications: Soil with 4% lime and 3% nanosilica gives good results, and the use of lime in soil stabilization contributes to the reduction of environmental pollution. The cost of nanosilica for real projects demands huge quantities. From an economic and commercial perspective, nanosilica liquid and lime are generally considered cost-effective for most practical applications. However, nanosilica with lime is recommended in areas where durability is important. Lime with soil is used to strengthen the soil in pavements and embankments; for example, when strengthening black cotton soil used for an embankment with a top width of 2 m, height of 6 m, side slope of 1:1, and length of 1 m, the volume is calculated as 48 m³. For soil +4% lime +3% nanosilica, the dry density is 17.1 kN/m³ and the moisture content is 14.9%. Considering this, the mass of the sample is obtained as 943 kN. Consequently, the required quantities are 38 kN (3,872 kg) lime, 28 kN (2,435 L) nanosilica liquid, and 877 kN (89,443 kg) of soil in its dry state. The cost of lime and nanosilica liquid depends on the location. [ABSTRACT FROM AUTHOR]

Compaction is an essential compression process for sedimentary soils. Compared with in-depth studies on granular soil behaviors, numerical modeling of clay compaction is still in its infancy. This study presents an all-atomic modeling framework to investigate the compaction of anhydrous montmorillonite from initially fully exfoliated platelets. The total number of interparticle contacts increased, and the mesopores were dominant during the formation of card-house structures. As the local fabrics evolved into book-house structures, the contact evolutions became predominant, and partial mesopores transformed into micropores. The coordinated deformations during the formation of compacted aggregates dramatically increased interparticle contacts, and so the micropores became dominant. After rebound, the interparticle contacts decreased and partial micropores were restored. The total potential energy decreased during contact evolutions due to the significant reduction in interaction potential energy between clay particles, while hysteresis was observed during coordinated deformations and rebound due to the changes in internal potential energy within deformed clay particles. The internal potential energy was primarily determined by the electrostatic forces except under significant deformations, where the van der Waals forces became dominant. The interaction potential energy remained unchanged with specific contact types but decreased significantly due to electrostatic interaction when contacts evolved. As computational capacity develops, a greater number of larger hydrated clay particles can be used to improve simulations of compaction and other macroscopic behaviors via all-atomic molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

Modular infusion (MI) is utilized to eliminate dry spot defects within complex multi-architecture composites by segregating and controlling flow fronts in-process. Compaction, employed to arrest in-plane flow, results in a crimp witness, which can be eliminated through MI fiber bed normalization. However, the MI normalization techniques generate voids within the cured components. To study the mechanisms that control the MI fiber bed normalization process, an in-process X-ray computed tomography (XCT) approach is developed to provide a visualization of fiber bed thickness and void distribution. Inner bag regulation during normalization is identified as the primary cause of the void generation. C-scans on a cured panel corroborate XCT findings, as well as validating the quality of the panel produced for subsequent mechanical test samples. Hence, it is demonstrated that the approach enables the optimization of a MI manufacturing process, which is supported by the findings of the mechanical characterization campaign. Flexural tests were carried out in three and four-point bend testing using samples cut from the panel, with Digital Image Correlation (DIC) providing comparative measurements for a baseline and MI case. Flexural testing of MI samples showed that a comparable mean strength and stiffness to that of the baseline material was achieved, demonstrating complete restoration of material thickness and mechanical properties during the optimised MI process. [ABSTRACT FROM AUTHOR]

Introduction. Forward plate compactors are surface soil compaction machines with a flat operating device, which are usually equipped with a single-shaft vibration exciter. Forward plate compactors may be driven by gasoline, diesel or electric engines. When designing and modernizing forward plate compactors, a problem of technical specifications justification may arise, including such parameters as exciting force, vibration exciter oscillation frequency, engine power, base plate width, etc. This statistical analysis of plate compactors with different types of engines was carried out to summarize manufacturers practices and reveal correlations between the technical specifications of forward plate compactors.Materials and methods. This research is based on the information presented on the official websites of forward plate compactors manufacturers and their dealers. 644 models of forward plate compactors were scrutinized. Regression equations and correlation coefficients were derived using Microsoft Excel software.Results. Parameters ranges for forward plate compactors with different types of engines were determined. Regression equations of correlations between oscillation frequency, exciting force, engine power, base plate width, relative exciting force and mass of forward plate compactors with different types of engines were derived, as well as the corresponding correlation coefficients. It was revealed, that most parameters have low or very low correlation coefficient, regardless of the engine type.Conclusion. The ranges of the technical specifications of diesel and gasoline forward plate compactors are quite close to each other. The parameters ranges of electric plate compactors, in most cases, are beyond the ranges of gasoline and diesel plate compactors. Low correlation coefficients and a large scatter of parameters indicate that manufacturers do not have a methodology for justification of the technical specifications of forward plate compactors. Results of the study may be used when clarify ranges of parameters and formulate requirements for a mathematical model of vibration plates behavior.

Water contamination in rural Malaysian areas, mainly caused by logging activities leading to soil erosion and river pollution, presents a significant threat to water supplies. In response, a specialized activated carbon water filtering device was developed to target the absorption of organic molecules. The impact of compaction of activated carbon on water filtering efficiency was evaluated. Testing both compacted and uncompacted activated carbon filters with contaminated river water, the study utilized the Malaysia Department of Environment's (DOE) water quality index (WQI) to assess filter effectiveness. The results revealed that water filtered through compacted activated carbon was clearer and less yellowish compared to the uncompacted counterpart. Moreover, the compacted filter showed higher dissolved oxygen levels, lower ammoniacal nitrogen levels, and a lower pH, resulting in a significantly higher WQI score of 80.4 compared to 78.8 for the uncompacted filter. Further analysis via an adsorption isotherm test demonstrated the superior ability of compacted activated carbon to absorb acetic acid, as evidenced by higher lines in the Freundlich isotherm model graphs. These findings emphasize the efficacy of compacted activated carbon in water filtration, advocating for its integration into filter construction to enhance water quality in rural regions.

The introduces new agrotechnological crop rotations is relevant in the context of environmental protection. The study aims to investigate the effectiveness of introducing two crop rotations on degraded lands in the Mykolaiv region, where active military operations were conducted. The study determined that the introduction of new crop rotations led to a 1.3-fold increase in gross output compared to previous data. In a five-field crop rotation, growing perennial grasses for green fodder together with annual grasses for silage restored soil fertility and increased yields by 30 c/ha compared to existing economic indicators. Oat yields with perennial grasses increased by 18 c/ha. Growing corn for silage and green fodder provided an additional 100 cwt/ ha. An increase in the yield of fodder roots and annual grasses for green fodder by 110 c/ha demonstrated the effectiveness of the new crop rotations. In a seven-season crop rotation, the introduction of perennial grasses increased soil fertility reduced soil erosion, and increased yields of winter wheat and sugar beet. Sugar beet yields increased by 25 c/ha, while potatoes and grain corn yields increased by 55 c/ha. The introduction of annual grasses, pulses and buckwheat helped to increase yields by 28 c/ ha. The results of the study can be used by local communities to develop and implement environmental measures and programmes aimed at restoring the structure and fertility of damaged lands and preserving their quality

Segregation in concrete significantly affects its durability and structural integrity by introducing local variance in both the strength distribution and the modulus of elasticity within a structural element. Additionally, segregation can lead to durability complications, such as shrinkage induced cracking. Recent observations have identified such segregation issues in already existing structures, underscoring the importance of assessing segregation. In this study, we evaluate the extent of segregation in normally vibrated concrete specimens, which were subjected to different vibration durations and vibrated using either table or poker vibrators. The research introduces three segregation indices to assess this phenomenon. One index relies on the standard deviation of densities across multiple slices of each specimen, while the other two utilize Digital Image Processing (DIP) to analyse the distribution of aggregates in horizontal and vertical slices, respectively. High correlations were found between the density-based index and vibration time for both poker-vibrated and table-vibrated specimens. The DIP-based indices showed strong correlations with the density-based approach, offering quicker alternatives for assessing segregation. The study further proposes classification levels for segregation based on these methods and reveals the negative impact of increased air entrainment on segregation. These findings provide insights for optimizing concrete compaction processes and understanding segregation.

Different types of models are used to study the stress-strain behavior of asphalt concrete mixture during compaction. For modeling it is necessary to know the values of model parameters in the whole range of changes in the characteristics of the compacted material. The aim of the paper is to develop a methodology for determining model parameters based on the results of laboratory creep-recovery testing of asphalt-concrete mixture. In the paper, a model reflecting elastic, visco-elastic and visco-fluid properties of the compacted material is adopted. A differential equation representing the law of behavior of the asphalt-concrete mixture layer under load is obtained. The stages of creep-recovery testing are analytically described, namely: rapid loading with a constant load and deformation under this load; load removal and recovery. Initial conditions for the mentioned stages are determined. Taking into account the initial conditions, analytical expressions of the laws of deformation of the model under the action of a constant load and in the process of recovery are obtained. The methodology of laboratory experiments on creep-recovery is described, according to the results of which the required values of the model parameters with minimum absolute error are obtained. The developed methodology allows to determine the parameters of the model describing the stress-strain behavior of asphalt-concrete mixture of different density and temperature. Consequently, it is possible to simulate the behavior of the asphalt concrete mixture layer at the preliminary, main and final stages of compaction in order to determine the effective operating modes of compaction equipment.

• This study has collected a database wide enough to demonstrate the validity of a correction factor that allows to accurately simulate the compaction behavior of multicomponent mixtures. • The possibility to apply a modelling approach to scale-up from compaction simulator to roller compaction would significantly improve the formulation development efficiency as it would avoid the need of performing experiments on the roller compactor itself. • One correction factor is identified as the optimal trade-off between the SF prediction accuracy on the roller compactor and its applicability to a wide range of formulations. Roll compaction (RC) is a cost-effective dry granulation method, widely implemented in the pharmaceutical industry. In early formulation development however, when the material availability is limited, being able to predict the most important parameters in RC, like gap width and specific compaction force (SCF), to obtain a target ribbon solid fraction (SF) would significantly improve the formulation development efficiency as it would avoid the need of performing experiments on the roller compactor itself. However, at the present state of things, experiments on RC mechanical simulators present an overestimation of the target SF, when compared to roller compactor SF values. Although numerous correction approaches have been developed to improve the predictive performance of different mathematical models applied to the simulation experimental results, no study has collected a database wide enough to demonstrate the validity of a correction factor that allows to accurately simulate the compaction behavior of multicomponent mixtures. Here, 25 different formulations at 40 % drug load are compacted at different SCFs, both on a RC mimicking device (Styl'One Evolution) and on an actual roller compactor (Gerteis Mini-Pactor): following a similar approach as Reimer et al. and implementing a simplified version of the Johanson's mathematical model, 4 different correction factors are calculated, depending on how their material properties and pressure dependencies are considered. In conclusion, one correction factor is identified as the optimal trade-off between the SF prediction accuracy on the Gerteis Mini-Pactor and its applicability to a wide range of formulations, as it is independent of the material properties. This finding is particularly relevant when applied to scale-up to this specific roller compactor or early development processes of new formulations that have not been mechanically characterized yet. [ABSTRACT FROM AUTHOR]

This study presents a methodology that includes hydraulic and mechanical constitutive relationships for modeling the complex volumetric behavior of unsaturated soils. The mechanical relationships are based on the generalized effective stress concept, and the hydraulic relationships adopt soil water retention curves dependent on soil deformation. After the formulation and the introduction of the governing equations, a study case based on the results of suction-controlled oedometric tests is presented, aiming for a better understanding of the effect of compaction on unsaturated soils. The oedometric compression curves of a first set of laboratory tests are reinterpreted in terms of the generalized effective stress concept to obtain the required model parameters. Then, numerical simulations are performed to analyze the soil susceptibility to large volumetric strains triggered by a combined effect of loading and wetting (collapse). The numerical simulations demonstrate that the proposed approach can model the collapse potential of soils with different compaction levels using a single set of parameters. [ABSTRACT FROM AUTHOR]

Crystal size distributions (CSD) of olivine were obtained for 17 samples of plagiodunite and Pl‑bearing dunite from the central part of the Yoko-Dovyren massif, northern Baikal region, Russia. Three types of CSD were identified: loglinear, bimodal, and lognormal. Combining these data with the results of petrological reconstructions, which earlier revealed two main types of the Dovyren magmas (using the method of geochemical thermometry), we proposed a basic scenario of interaction between magmatic suspensions of different temperature to explain the diversity of the CSD. The intratelluric olivine transported by magmas of different temperature, which had not subjected to abrupt cooling or heating in the chamber, retained an original loglinear CSD. For some portions of the hottest magma (∼1290°C), it is assumed that the original olivine evolved into a bimodal CSD due to accelerated crystallization at faster cooling of the high-temperature injections contacting relatively cold crystal mush (∼1190°C). An interpretation of the lognormal CSD suggests that part of the olivine crystals composing the protocumulate systems efficiently interacted with the pore melt infiltrating upward during the compaction of the underlying crystal mush. This led to cycles of partial dissolution and regrowth of the olivine grains resulting in a final lognormal CSD. The infiltrating hot melt, which was undersaturated with immiscible sulfide liquid, could dissolve sulfides preexisting in the low-temperature mush. This produced dunites with lognormal CSD relatively depleted in sulfur and chalcophile elements. The lognormal CSD is considered to be a marker of crystal mush regions through which the focused infiltration of the pore melt proceeded. [ABSTRACT FROM AUTHOR]

Submarine hydrate mining can trigger geological disasters, including submarine landslides and seafloor subsidence due to excess pore pressure and weakened layers, which may potentially lead to the reactivation of faults and increased seismic activity. However, current research encounters challenges in assessing geotechnical issues associated with long-term and large-scale production from well grids located in sloped areas. Limited by the complexity of the hydrate sediment, a multifield coupled numerical model of hydrate slope in the Shenhu area was established. Utilizing the modified Mohr–Coulomb model as the constitutive model for hydrate-bearing sediments to track the dynamic reduction in strength and employing the shear strength method to assess submarine slope stability, a series of depressurization strategies are applied to evaluate the risks associated with submarine landslides and seafloor subsidence. Results show that the hydrate dissociation tends to stagnate after a period of mining. The strength of the hydrate decomposed area is severely reduced, and a volume deficit occurs in this area, causing formation displacement. The peripheral region of the decomposed area is compacted by high stress, resulting in a serious decrease in permeability and porosity, which limits the continued decomposition of hydrates. The large-scale submarine landslides with hydrates decomposition will not appear in this block. However, several meters' seafloor subsidence over a wide range risks engineering safety significantly. The amount of seafloor subsidence in the first 50 days is approximately half of the final settlement. A higher production pressure drop can speed up the recovery rate while resulting in more significant seafloor subsidence and slippage. Therefore, the balance between mining speed and formation stability needs more research work. [ABSTRACT FROM AUTHOR]

Although pervious reduces surface runoff and replenishes groundwater resources, industrial applications are hindered by uncertainty in properties during mass productions. Most experimental studies correlated design parameters to performance parameters predominantly analysing porosity measured from water replacement method. This explains only a fraction of porosity and leads to inappropriate correlations between the influencing parameters. This study quantified porosity using a novel image analysis. 480 samples of pervious concrete were cast varying aggregate to cement ratio and compaction levels and performance parameters such as, wet-density, compressive strength, apparent, actual and effective porosities were assessed. The developed novel image analysis method facilitates accurate computation of porosity and actual, apparent and effective porosities was analysed quantified and optimised. An optimum A/C ratio was observed as 4.0 corresponding to 30 blows of compaction and a resultant actual porosity of approximately 0.2. Further the study establishes relationships between different types of porosities and their performance implications. [ABSTRACT FROM AUTHOR]

The structural integrity of myelin sheaths in the central nervous system (CNS) is crucial for the maintenance of its function. Electron microscopy (EM) is the gold standard for visualizing individual myelin sheaths. However, the tissue processing involved can induce artifacts such as shearing of myelin, which can be difficult to distinguish from true myelin abnormalities. Spectral confocal reflectance (SCoRe) microscopy is an imaging technique that leverages the differential refractive indices of compacted CNS myelin in comparison to surrounding parenchyma to detect individual compact myelin internodes with reflected light, positioning SCoRe as a possible complementary method to EM to assess myelin integrity. Whether SCoRe is sensitive enough to detect losses in myelin compaction when myelin quantity is otherwise unaffected has not yet been directly tested. Here, we assess the capacity of SCoRe to detect differences in myelin compaction in two mouse models that exhibit a loss of myelin compaction without demyelination: microglia-deficient mice (Csf1r-FIREΔ/Δ) and wild-type mice fed with the CSF1R inhibitor PLX5622. In addition, we compare the ability to detect compact myelin sheaths using SCoRe in fixedfrozen versus paraffin-embedded mouse tissue. Finally, we show that SCoRe can successfully detect individual sheaths in aged human paraffin-embedded samples of deep white matter regions. As such, we find SCoRe to be an attractive technique to investigate myelin integrity, with sufficient sensitivity to detect myelin ultrastructural abnormalities and the ability to perform equally well in tissue preserved using different methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the straw to decrease the bulk density of sandy clay loam and clay soils and to determine the effect of this on the development of soybean and maize plants. The soils were compacted using Proctor test with different amounts of crushed straw on the soil surface corresponding to 0, 3, 6, 9 and 12 t ha−1. After this, the soils in pots were compacted with same levels of straw on its surface using the maximum bulk density each soil. Then, soybean and maize were sown and after 42 days, biometric characteristics and physiological parameters were evaluated. The results showed that the maximum bulk density and critical soil moisture for the sandy clay loam soil were 1.51 t m−3 and 0.15 kg kg−1, respectively, while those for the clay soil were 1.54 t m−3 and 0.19 kg kg−1. The straw reduced soil compaction for the two soils, resulting in lower soil bulk density with 9 and 8 t ha−1 of straw on the surface of sandy clay loam and clay soils, respectively. When evaluated the plant, the amounts 6 to 9 t ha−1 of straw promoted better initial development of soybean and maize plants. Thus, this study suggests that a minimum of 6 and 8 t ha−1 of straw be used on the surface of sandy clay loam and clay soils, respectively were efficient in promoting physical soil improvements and better plant development. [ABSTRACT FROM AUTHOR]

Diagenetic physical simulation is a reliable means to study patterns of pore evolution and variations of physical properties, however, the current compaction model is mostly based on sandstone, and there is a lack of quantitative compaction and porosity reduction studies for more complex rock fabrics. In order to simulate the continuous change of intergranular porosity in the reservoir under compaction during the diagenesis of buried sedimentary strata, a self-designed diagenesis simulation experimental system was adopted. Using different modern sediment samples, the simulation experiment of mechanical compaction of glutenite was carried out. The experiment shows that during the process of mechanical compaction of glutenite, the change of porosity with depth is segmented, and there is a good logarithmic relationship between depth and porosity in the process of diagenetic compaction. The larger the grain size in the reservoir rock, the better the pore preservation capacity; When the sand particles fill the pores among gravel, stable secondary support structure formed by gravel and sand grades can effectively take over the bearing pressure, and when the sand-grade particle content is about 30%, the pressure-bearing capacity is the strongest; Intergranular heterobase filling is greater in samples with high heterobase content, high heterobasic content is not favourable to the preservation of primary pores. This study provides favorable experimental support for the preservation mechanism of deep clastic reservoir pores, and has important theoretical and practical significance for oil and gas exploration in the study area. The use of simulation experiment provides a useful idea for the evaluation and prediction of reservoirs and the search for favorable reservoir development zones in the future. [ABSTRACT FROM AUTHOR]

In the Cerrado Biom, a commonly used intercropping is between corn species and Urochloa, however, there are alternative grasses able to improve the corn intercropping, such as those of genus Panicum. Studies show that diversified crop rotation improves the efficiency of the agricultural system. Thus, it was aimed to evaluate the effect of the corn (Zea mays) and Zuri grass (Panicum maximum BRS Zuri) grown in the monoculture or intercropped under conditions with and without soil scarification in chemical and physical soil attributes. For this, an area under Red Oxisoil was used, in which part was scarified up to 30 cm deep and the other was not. In February 2020, corn and Zuri grass were planted in cultivar sole system or intercropped between the two species in compacted and scarified area, creating six evaluation areas. After the crop cycle, with corn harvest and Zuri grass crushing, soil sampling was carried out for evaluations at five points in each area. Corn in monoculture had lower soil moisture and greater resistance to penetration. And the soil without scarification had a higher C stock. The results showed that the Zuri grass using after soil revolving can be applied as a management strategy, looking to dry mass accumulation, bigger carbon stock and soil porosity, improving soil conditions for the summer crop. Besides that, the intercropped used improves the chemical soil conditions. [ABSTRACT FROM AUTHOR]

Water contamination in rural Malaysian areas, mainly caused by logging activities leading to soil erosion and river pollution, presents a significant threat to water supplies. In response, a specialized activated carbon water filtering device was developed to target the absorption of organic molecules. The impact of compaction of activated carbon on water filtering efficiency was evaluated. Testing both compacted and uncompacted activated carbon filters with contaminated river water, the study utilized the Malaysia Department of Environment's (DOE) water quality index (WQI) to assess filter effectiveness. The results revealed that water filtered through compacted activated carbon was clearer and less yellowish compared to the uncompacted counterpart. Moreover, the compacted filter showed higher dissolved oxygen levels, lower ammoniacal nitrogen levels, and a lower pH, resulting in a significantly higher WQI score of 80.4 compared to 78.8 for the uncompacted filter. Further analysis via an adsorption isotherm test demonstrated the superior ability of compacted activated carbon to absorb acetic acid, as evidenced by higher lines in the Freundlich isotherm model graphs. These findings emphasize the efficacy of compacted activated carbon in water filtration, advocating for its integration into filter construction to enhance water quality in rural regions. [ABSTRACT FROM AUTHOR]

To design and operate various equipment of the solids control system in offshore drilling platforms, it is important to establish how the moisture content influences the characteristics of drilled cuttings to form packed beds and flow over solid surfaces. The current study comprehensively analyzes how moisture content, primarily composed of water and representing waterbased muds (WBMs), influences the bed packing properties and drilled cuttings' flowability. The particle aggregation/disaggregation dynamics, loose and tapped bulk densities and porosities, compaction dynamics of packed beds, Hausner ratio, and angle of repose of drilled cuttings with ten distinct moisture contents (1.4--44.0 wt%) were analyzed. It was noticed that the increment of moisture content up to 15.2% promoted the formation of looser interparticle structures. However, these structures were steadier, showing greater difficulty flowing and releasing air/liquid. The continuous increment of moisture content beyond 15.2% promoted a complete change in the material behavior. The interparticle structures became denser. The material could flow and release air/liquid more easily. In addition, it was possible to establish a classification of the different behaviors of drilled cuttings according to the moisture content. Predictive models were proposed to describe the influence of the moisture content on the bed packing and flowability properties of drilled cuttings. [ABSTRACT FROM AUTHOR]

The North Island of New Zealand is a region of high volcanic activity, with significant eruptions over the past. Analogous to past events, future volcanic eruptions would produce a considerable volume of ash and granular soils, covering widespread areas and raising concerns for their disposal and storage. Such deposits, primarily airfall tephra, could be potentially used in geotechnical engineering applications such as foundations, roadway embankments and land reclamations. However, before their use as structural fills can be recommended, detailed laboratory investigations of their physical, chemical, compaction, and geotechnical engineering properties (strength, compressibility, collapsibility, liquefaction potential, etc.) must be conducted. Different tephra deposits can be products of different eruptions, so chemical composition analyses can be combined with the physical, compaction, and engineering properties to characterize such deposits. Accordingly, this paper provides useful insights from physical (grain size, specific gravity, and morphology), chemical (elemental and mineralogy using X-ray fluorescence and X-ray diffraction), and compaction tests (maximum dry density, optimum water content, and particle breakage) for eleven selected volcanic tephra samples sourced from the North Island of New Zealand in the Rotorua, Taupo, and Auckland regions. [ABSTRACT FROM AUTHOR]

The present research assesses possible effect(s) of relative in situ compaction energy and grain size gradation on compaction parameters of remoulded geological materials. Ten (10) points, in North-eastern Nigeria, were each drilled to 60 m to create seismic refraction data acquisition wellbores and also recover remoulded geological materials. The seismic acquisition was to ascertain velocities and thicknesses of lithoseismic layers occurring from 0 to 60 m depth. The remoulded materials collected from each lithoseismic layer were subjected to sieve analysis and compaction test. The sieve was to determine their grain size gradation while the compaction was to determine their compaction parameters viz: optimum moisture content (OMC) and maximum dry density (MDD). The seismic acquisition revealed the occurrence of weathered layers with velocities (Vp) and thicknesses (T) ranging from 351 m/s to 629 m/s and 3.4 m to 11.9 m respectively; sub-weathered layers with Vp and T ranging from 830 m/s to 1507 m/s and 21.4 m to 48.2 m respectively; and unweathered layers with Vp ranging from 1607 m/s to 2023 m/s. The remoulded materials were composed of mostly sand and fine particles. Thicknesses and sand content affect the velocities of weathered lithoseismic layers. The weathered materials have OMC and MDD ranging from 12.71 to 21.58% and 1.54 to 1.88 mg/m3 respectively; sub-weathered materials have OMC and MDD ranging from 9.20 to 19.66% and 1.55 to 2.01 mg/m3 respectively while unweathered materials have OMC and MDD ranging from 10.32 to 23.11% and 1.41 to 1.92 mg/m3 respectively. The sub-weathered remoulded materials attained MDD at lower OMC relative to the weathered remoulded materials. Grain size gradation controlled the MDD of the unweathered materials more than lithoseismic layering. This work has shown that in situ compaction of geological materials manifest in their remoulded compaction parameters and this is to be considered when using geological materials as pavement bases or fillings. [ABSTRACT FROM AUTHOR]

Binary mixtures of plastic fines and a non-cohesive host material are used in geotechnical barriers to obtain high shear strength and low permeability. To achieve such properties, the sand grains must form the force chain and the clay must fill the voids of the host material. However, clays are known to affect the grain to grain contacts by forming cohesive membranes. Since engineered barriers are usually compacted at water contents below saturation (Proctor conditions), it is still unclear whether such membranes will form. The aim of the current research is to shed light on the compaction characteristics of such mixtures. Proctor datasets were analysed in terms of skeleton and fines void ratio and optimal water content. Oedometric compression behaviour and limiting void ratios were studied to outline the characteristics of mixtures in a saturated or dry state, respectively. The results show that depending on the mixing ratio, compaction properties can be divided into three different ranges, where either the properties of one of the input materials dominate the behaviour or a transitional range exists that is characterised by a strong mutual influence of both materials. Furthermore, even a small amount of the highly plastic clay was found to influence the properties of the host sand. [ABSTRACT FROM AUTHOR]

Asphalt concrete core dams (ACCDs) have been widely constructed in Xinjiang, yet the design of materials and structures has mainly relied on empirical knowledge without substantial theoretical grounding. In this study, we carried out a large-scale relative density test of gravel material in Bamudun dam, studied the compaction characteristics of gravel material, and determined the relative density characteristic index, in order to provide a basis for the subsequent dam material rolling test and construction quality inspection. Furthermore, in order to improve the efficiency of dam construction in narrow valleys, we optimized the connection type between asphalt concrete core wall and bedrock, and proposed a rapid construction method of paving core wall after pouring mass concrete base on bedrock. Finally, we established a three-dimensional finite element model to systematically analyze the stress and deformation patterns of the dam body, core wall, and base of the ACCD at Bamudun. The results show that the maximum compressive stress suffered by the core wall during the full storage period is 1.62 MPa, there is no tensile stress, and the risk of hydraulic splitting is small. The stress and deformation levels of each part are within the safe range. This verifies the rationality of the rapid construction method. The research findings can provide a great theoretical significance and engineering value for the safe design and construction of ACCDs. [ABSTRACT FROM AUTHOR]

Potential soil production is closely related to the physical and mechanical properties. The aim of this paper was to evaluate the effect of different levels of soil compaction created by tractor chassis. The total area of the experimental plot was 13.22 ha. Up until 2019, a conventional tillage system had been used. The measurements were carried out with an innovative measuring device that allows for the continuous measurement of the horizontal penetrometry for comparative measurements while driving, which was designed at the Slovak University of Agriculture in Nitra. The measuring device measured the soil resistance in the tire track (On-track) and out of track (Off-track) as well as in three (50 s) sequences within one tractor pass. Three lines were chosen, where in each a pair of combinations was made. The results were subjected, in addition to graphical evaluation, to single factor ANOVA analysis. When comparing individual passes (PH1 to PH6), the statistical analysis showed that the results of the horizontal resistance measurements proved to be statistically significant (p < 0.05) with respect to the weight, number of passes, and tire underinflation. The highest compaction was caused by the first pass, while the higher weight of the tractor during the next pass had a smaller effect. Underinflating the tires ensured a reduction in compaction. Reducing the tractor tire pressure to 0.15 MPa resulted in a reduction in soil compaction of up to 16%. [ABSTRACT FROM AUTHOR]

When dealing with processes involving the compaction of bulk materials, very often the quality of the product is determined based on density measurements. Methods used in the industry do not produce compacted materials with high degrees of homogeneity. As a result, the quality of the resulting product, interpreted as its density, varies over the cross-section of the product. In this article, the authors present the results of a numerical study involving the analysis of the density distribution of compacted dry ice during the reciprocating process. The Drucker–Prager/cap model was used in this study, which allowed the change in mechanical properties of the compacted material to be taken into account during the simulation of the process. The diameter, height and density of the cylindrical specimens used in the numerical tests were taken as the variable parameters. Thus, as a result of the testing, the authors could formulate conclusions relating to their impact on the homogeneity of the material. [ABSTRACT FROM AUTHOR]

This article showcases the findings of an experimental study conducted on a red siltclayey taken from the site of Chaaba Elhamra (M'sila region, Algeria) for the purpose of being used for the building of road embankments and pavement layers. This experimental research aims to evaluate the geotechnical characteristics of this red soil, both before and after being treated with two classes of cement (CEM-II/B-L 32.5 N and CEM-II/B-L 42.5 N), and to analyse the impact of the cement class on its geotechnical properties. The experimental program included identification tests as well as Proctor compaction, CBR, and unconfined compression tests. The interpretation of the results has taken into account knowledge acquired from the literature. The findings showed that the percentage of cement had a beneficial effect on the geotechnical characteristics of this red silt-clay. Moreover, they highlighted that the type of cement did not have a great influence on the physical parameters, the compaction parameters, and the CBR indices. However, it was observed that class 42.5 cement had a much greater effect on UCS values than lower class 32.5 cement. [ABSTRACT FROM AUTHOR]

Most of the materials used in landfill liners are not based on the local soil conditions which increases the cost of landfill construction. It is essential to develop a composite mix based on local soil that fulfills the design parameters of the municipal solid waste (MSW) landfill at a reasonable cost as per USEPA 1989 guidelines. The current study investigates the use of local soil, fly ash, and bentonite mixtures to obtain an optimum composite mix with specific properties for landfill liners. The experimental investigation was conducted on different proportions of local soil-bentonite-fly ash mixes to evaluate the optimum mix proportion for liner materials. The curing period of different mixes is also considered. The geotechnical properties like liquid limit (LL), free swell index (FSI), and optimum moisture content (OMC) increased whereas the maximum dry density (MDD) and permeability decreased with an increase in bentonite content up to 20% with soil. It was also observed that fly ash mixed with soil in proportion (80:20) meets the optimum range of landfill liner properties. And, the composite mix comprised of soil–bentonite–fly ash in proportion (65:15:20) directs toward the optimum design parameters of landfill liner. These mixes were compacted at OMC and MDD satisfying plasticity (i.e., LL ≥ 20% and plasticity index, PI ≥ 7%) and permeability criteria (k ≤ 1 × 10−7 cm/s) as well as unconfined compressive strength criteria. Moreover, the scanning electron microscopy of local soil–bentonite–fly ash mixes was investigated for the optimum mixes for a comparative assessment of results. [ABSTRACT FROM AUTHOR]

That the highly trabeculated ventricular walls of the developing embryos transform to the arrangement during the fetal stages, when the mural architecture is dominated by the thickness of the compact myocardium, has been explained by the coalescence of trabeculations, often erroneously described as 'compaction'. Recent data, however, support differential rates of growth of the trabecular and compact layers as the major driver of change. Here, these processes were assessed quantitatively and visualized in standardized views. We used a larger dataset than has previously been available of mouse hearts, covering the period from embryonic day 10.5 to postnatal day 3, supported by images from human hearts. The volume of the trabecular layer increased throughout development, in contrast to what would be expected had there been 'compaction'. During the transition from embryonic to fetal life, the rapid growth of the compact layer diminished the proportion of trabeculations. Similarly, great expansion of the central cavity reduced the proportion of the total cavity made up of intertrabecular recesses. Illustrations of the hearts with the median value of left ventricular trabeculation confirm a pronounced growth of the compact wall, with prominence of the central cavity. This corresponds, in morphological terms, to a reduction in the extent of the trabecular layer. Similar observations were made in the human hearts. We conclude that it is a period of comparatively slow growth of the trabecular layer, rather than so‐called compaction, that is the major determinant of the changing morphology of the ventricular walls of both mouse and human hearts. [ABSTRACT FROM AUTHOR]

The introduces new agrotechnological crop rotations is relevant in the context of environmental protection. The study aims to investigate the effectiveness of introducing two crop rotations on degraded lands in the Mykolaiv region, where active military operations were conducted. The study determined that the introduction of new crop rotations led to a 1.3-fold increase in gross output compared to previous data. In a five-field crop rotation, growing perennial grasses for green fodder together with annual grasses for silage restored soil fertility and increased yields by 30 c/ha compared to existing economic indicators. Oat yields with perennial grasses increased by 18 c/ha. Growing corn for silage and green fodder provided an additional 100 cwt/ha. An increase in the yield of fodder roots and annual grasses for green fodder by 110 c/ha demonstrated the effectiveness of the new crop rotations. In a seven-season crop rotation, the introduction of perennial grasses increased soil fertility reduced soil erosion, and increased yields of winter wheat and sugar beet. Sugar beet yields increased by 25 c/ha, while potatoes and grain corn yields increased by 55 c/ha. The introduction of annual grasses, pulses and buckwheat helped to increase yields by 28 c/ha. The results of the study can be used by local communities to develop and implement environmental measures and programmes aimed at restoring the structure and fertility of damaged lands and preserving their quality. [ABSTRACT FROM AUTHOR]

This review, complemented by empirical investigations, delves into the intricate world of industrial powders, examining their elastic properties through diverse methodologies. The study critically assesses Young's modulus (E) across eight different powder samples from various industries, including joint filler, wheat flour, wheat starch, gluten, glass beads, and sericite. Employing a multidisciplinary approach, integrating uniaxial compression methodologies—both single and cyclic—with vibration techniques, has revealed surprising insights. Particularly notable is the relationship between porosity and Young's modulus, linking loose powders to the compacts generated under compression methods. Depending on the porosity of the powder bed, Young's modulus can vary from a few MPa (loose powder) to several GPa (tablet), following an exponential trend. The discussion emphasizes the necessity of integrating various techniques, with a specific focus on the consolidation state of the powder bed, to achieve a comprehensive understanding of bulk elasticity. This underscores the need for low-consolidation methodologies that align more closely with powder technologies and unit operations such as conveying, transport, storage, and feeding. In conclusion, the study suggests avenues for further research, highlighting the importance of exploring bulk elastic properties in loose packing conditions, their relation with flowability, alongside the significance of powder conditioning. [ABSTRACT FROM AUTHOR]

Road networks facilitate socioeconomic growth in developing countries, such as the Philippines. An increased traffic volume exacerbates the gradual progression of erosion, breaching, and degradation of road embankments. Weathered marble from local quarries in Norzagaray, Bulacan, was repurposed to provide an economic solution. This study quantified the effect of five varying proportions of weathered marble and aggregate on index properties, such as specific gravity, grain size distribution, plasticity, and compaction, and assessed the capacity of the embankment against vehicular loads using the California bearing ratio and direct shear tests. A mix of 60% marble and 40% aggregate (60M40A) was determined to display the best performance in terms of maximum dry density (20.512 kN/m3) and California bearing ratio (78%). The Proctor compaction test results indicated a very stable embankment according to the USCS criteria and good to excellent embankment performance according to the AASHTO criteria. The local criteria on embankment marked the 60M40A samples as an excellent material for the embankment base layer. The same specimen demonstrated the highest shear strength before failure and had the highest friction angle before failure (37 degrees). These results indicate that weathered marble exhibits excellent compaction behavior, yields friction angles comparable to well-graded soil, and possesses a suitable load-bearing capacity, thus establishing its feasibility as a potential material for road embankments, especially in rural areas within proximity to marble quarrying sites. [ABSTRACT FROM AUTHOR]