Different Types Of Aggregates Research Articles

A Methodological Approach to the Study of Retroreflective Pavements

Climate change, principally driven by human activities, has led to an increase in global temperature, which is predicted to continue rising in the coming years. This temperature increase is even more pronounced in urban areas due to the heat island effect. This phenomenon is highly influenced by the presence of paved streets made with bituminous mixtures, which are characterised by their high solar radiation absorption capacity. Bituminous mixtures retain and re-emit a large amount of heat that intensifies the urban heat island effect. The novelty of this work is to measure retroreflective properties of bituminous mixtures that present a highly textured surface. In this context, the aim of this study is to evaluate the retroreflectance of different bituminous mixtures for use as pavement surfaces, focusing on the influence of colour and different types of aggregates. For this, total and directional reflectance measurements were conducted to determine the retroreflectance of these mixtures, with the purpose of mitigating the heat island effect in urban environments without affecting users through reflected solar radiation. The results show the retroreflective capacity of the designed mixtures within the visible spectrum, especially those manufactured with light-coloured aggregates and synthetic binders pigmented with titanium dioxide. Thus, the retroreflectance of the lighter mixtures range from 37.9% at a 0° entrance angle to 68.9% at 60°, while the black mixtures exhibit values between 5.1% and 8.4%.

Mechanical Characteristics of Hardened Concrete with Different Types of Cement and Aggregate Available in Bangladesh

This paper presents the results of an investigation on the influence of aggregate and binding material type on the mechanical properties of hardened concrete. To perform this investigation, four different types of coarse aggregate (Brick Aggregate, Recycled Brick Aggregate, Black Stone and Shingles) and eight types of binding material [Ordinary Portland Cement (OPC), CEM Type II B-M, CEM Type II B-M-SL, 40% OPC – 60% Slag CEM IIIA, 80% OPC – 20% Slag(CEM II/A-S), 70% OPC – 30% Slag(CEM II/B-S), 30% OPC –70% Slag(CEM-IIIB), 15% OPC –85% Slag(CEM-IIIC)] have been used. Aggregates were collected and prepared according to grading requirements of ASTM C33-03. Several tests as specific gravity, absorption capacity, unit weight and abrasion resistance were performed for coarse aggregate. Cylindrical concrete specimens of diameter 100 mm and length 200 mm were made with different W/C ratio (0.45 and 0.5) and cement content (340 kg/m3 and 400 kg/m3). A total of 42 different cases were considered for testing. The specimens were tested for compressive strength, stress-strain curve and Young’s modulus at the age of 28 days. Non-destructive test as Ultrasonic Pulse Velocity (UPV) were also performed. To conduct UPV test Portable Ultrasonic Non-destructive Digital Indicating Tester (PUNDIT) were used. The major objective of this study was to investigate the mechanical characteristics of concrete for different types of aggregate and binding materials. The significance of those results is discussed here.

Optimising load control of multi-type air conditioning in demand-side management

ABSTRACT With the continuous expansion of renewable energy capacity and the increasing demand for thermostatically controlled loads in China, new challenges have arisen for maintaining power supply stability. This paper establishes a control model for the aggregation of different types of air conditioning loads. To improve unsatisfactory demand response outcomes, a novel incentive mechanism based on tracking the target load curve is proposed. Additionally, a cost model for air conditioning load aggregators and the regional grid operator, along with an implementation scheme for trading mechanisms, is also developed. Case simulations validate the effectiveness and rationality of the proposed incentive mechanism.

Decomposer faecal food web and C sequestration in soil. Can near infrared spectroscopy describe transfers and transformations from fresh organic inputs to protected forms in soil aggregates?

This study sought to characterize the transfer of agricultural organic inputs by macrofauna to the biogenic aggregate compartments of the soil and test the existence of a faecal food web process based on coprophagic feeding behaviours. In an experimental plantain crop field of Colombia, we applied the agroecological FBO (Fertilisation Bio Organique ®) technology, a nucleation technique which consists in planting perennial plants in 1.0 x 0.4 × 0.4 m deep trenches where low- and high-quality organic materials are added in a specific design, and endogeic earthworms are inoculated. We evaluated the effectiveness of Near Infrared Spectroscopy (NIRS) to track this flow of organic matter through different natural stages of decomposition represented by soil macroaggregates produced by soil macroinvertebrates as faecal pellets and casts. After one year, great part of the organic inputs had been either mineralized or incorporated into macroaggregates of different sizes and origins. Using NIRS and physicochemical laboratory analyses, we assessed the quality and quantity of organic matter in the different types of aggregates separated manually according to their origin: large biogenic aggregates (LBA), medium sized biogenic aggregates (MBA) and small biogenic aggregates (SBA); physical aggregates (PA), root aggregates (RA) and residual soil (RS).Earlier studies had shown that these structures were presumably formed by the activity of macroinvertebrates of three different functional groups, Diplopoda and Isopoda litter transformers for SBA, epidendogeic earthworms for MBA and mesohumic endogeic earthworms for LBA, organized in a feeding succession.A Coinertia analysis between showed significant covariation among the two sets of physico chemical (22 variables) and NIR spectral (100 different wavelength absorbances) characterization of 135 samples representative of the three classes of biogenic macroaggregates, physical aggregates and residual non macroaggregated soil, (RV = 0.55; p < 0.001). This analysis clearly separated biogenic structures and ranked them according to their size, from small SBA to medium sized MBA and large LBA. Physical PA aggregates and RS residual soil were projected close to the LBAs in the coinertia factorial plan. Multiple combinatorial data analysis CDA, associated 5 specific wavelength absorbance ranges with aggregate types and residual soil. Along the sequence from small to large biogenic aggregates, residual soil and physical aggregates, wavelengths associated to easily decomposed substrates (in ranges 1708–1716 nm; 1796–1948 and 2164–2316 nm) had progressively decreasing absorbances. Substrates associated to slowly decomposing aromatic, alkane and phenolic substrates either increased (1420–1436) or decreased (1284–1380) along this sequence.These results are compatible with the hypothesis of a progressive transformation and transfer of organic residues first into small biogenic aggregates that are presumably faecal pellets of Isopoda and Diplopoda, then to medium sized biogenic aggregates identified as casts of epiendogeic earthworms and finally to large biogenic aggregates expected to be the casts of the large endogeic earthworms present in these soils. A definitive verification of the hypothesis and the involvement of specific macroinvertebrates will require direct experimentation in controlled laboratory conditions.

Analysis of the effect of aggregate type on the dynamic behaviour of concrete

This paper focuses on how different aggregate types affect the dynamic response of concrete. While Split Hopkinson Pressure Bar (SHPB) is commonly used to assess dynamic behaviour through the dynamic increase factor (DIF), the specific influence of aggregate type, a major component of concrete, remains unclear. This influence is investigated using fast Fourier transform analysis of strain signals. Two different types of aggregates, sandstone and schist, with distinct geological origins and mineral compositions, are used to examine this effect. Energy analysis is performed to understand how aggregate type affects energy absorption. The fineness modulus of fractured specimens is also determined which allow the comparison of post-fracture grain sizes. A crucial link between aggregate type and dynamic response of concrete is observed. Stiffer aggregates lead to stiffer concrete, which influence the frequency of energy responsible for damage initiation. At lower strain rates, concrete with stiffer aggregates absorbs lower-frequency energy. However, as strain rate increases, the frequency of absorbed energy becomes more dependent on the extent of damage within the aggregates themselves. The type of aggregate also significantly affects the size distribution of the fractured material. To analyse the stress distribution under dynamic loading, numerical simulations are carried out. These simulations showed that the maximum stress in concrete is related to the stiffness of the aggregate.

Physico-Mechanical Characterization of Masonry Mortars for Sustainable Construction: Experimental Study with Four Different Aggregates

The construction sector generates a strong environmental impact every year as a result of the high consumption of raw materials and the large waste volumes associated with this productive activity. In this sense, the search for alternative and sustainable solutions that allow progress towards responsible economic growth has become a priority activity. This work presents an exhaustive characterisation of masonry mortars made with four different types of aggregates: standard sand, natural sand, concrete waste recycled sand and ceramic components recovered sand. Differently from other studies, this research addresses the previous characterisation of the aggregates as raw material for the manufacture of masonry mortars, and, afterwards, a study of the most relevant properties for these cement composites in the fresh and hardened state is carried out. The most relevant properties of the mortars made with these raw materials are presented, and the repercussion of aggregate washing on their physical-mechanical characteristics is analysed. The results show how mortars made with 100% recycled aggregate can be competitive in the industry, presenting excellent properties in the fresh state and achieving an optimal mechanical strength. In addition, it has been observed that the introduction of a previous washing step of the aggregates improves their physical-mechanical properties and results in a higher quality of the cement mortars finally produced. In this way, the most representative properties of this type of materials have been collected in a well-structured and complete way, thus showing their possibilities of application in the construction industry.

The influence of measurement conditions on the determined values of thermal parameters of different types of concrete

In recent years, great emphasis has been placed on the introduction of energy-saving solutions to the construction sector. Building envelopes made of concrete with a specially selected composition give great opportunities in this regard. As part of a wide-ranging experiment, the authors undertook to diagnose how much thermal conductivity, volumetric specific heat and thermal diffusivity can be improved with an aerating admixture and different types of aggregates. Three groups of composites were tested: B1 – on stone aggregate, B2 – on expanded clay aggregate, B3 – on sintered fly ash aggregate. Each of the groups was divided into 4 formulations made without an aerating admixture and with its increasingly higher content of 0.8, 1.1, 1.4% in relation to the weight of cement. The thermal parameters were measured on the top (T) and bottom (B) surfaces of 36 rectangular samples (3 samples from each of the 12 mixtures) with the ISOMET 2104 apparatus. Diagnostic tests concerning the influence of measurement conditions were carried out on dry and water-saturated samples. It has been proven that for each composite and in both conditions, the values of thermal parameters determined on the lower surfaces will not correctly describe the properties of the real structure present in the main volume of the element. Only measurements carried out on surfaces with a structure corresponding to the interior of the element provide adequate data that can be used in decision-making processes and in numerical simulations to assess the real thermal qualities of building envelopes.

Influence of Elevated Temperatures on the Compressive Strength of Concrete Made with Different Types of Aggregate

Concrete, the backbone of modern infrastructure, exhibits varying mechanical behaviour that depends on its components, with aggregates playing a crucial role in its strength and durability. This study aimed to investigate the influence of elevated temperatures on the compressive strength of concrete made with different types of aggregate. A comprehensive evaluation of concrete mixes was conducted using quartz, crushed clay bricks, crushed andesite, expanded clay and expanded glass coarse aggregates. For each coarse aggregate type, concrete mixtures were made with the same amount of Portland cement, water-cement ratio, natural sand, and superplasticizer. The effective water-cement ratio and cement content were kept constant in each concrete mixture. The grading and maximum particle size were the same in all concrete mixtures. The results revealed that the type of aggregate has a significant impact on the compressive strength and thermal resistance of concrete, with andesite-containing concrete exhibiting the highest residual strength after heating up to 800 °C and clay brick-concrete displaying the highest strength under elevated temperatures up to 1000 °C. The study also found that the age of concrete affects its strength at elevated temperatures, as concrete in the early stages of hydration is more susceptible to thermal cracking than concrete that has had more time to cure. Generally, the compressive strength of normal-weight aggregates depends on the strength of the parent rock. But in the case of fire (elevated temperature), the cement paste matrix loses its strength, and the aggregates effects become more significant.

FEATURES OF CREATION OF THE SMART MONITORING SYSTEMS FOR MICROGRIDS

In this paper, an analysis of the main requirements for control systems in Microgrid is conducted. The main objectives of the implementation of Microgrid systems were determined and, based on the performed analysis, the requirements for Smart-monitoring systems were systematized. The components of Smart-monitoring systems, which include: communication software platform, hardware communication platform and types of equipment of DG sources for Microgrid systems were analyzed. It is proposed to build Smart-monitoring systems for Microgrid systems on the basis of the SGAM model, taking into account various models of aggregation of different types of DG sources within the framework of Microgrid systems. The proposed structure of the Smart-monitoring system for Microgrid systems with various DG sources makes it possible to effectively aggregate DG sources and prosumers and to carry out effective dispatching of generating capacities based on market mechanisms of their interaction with consumers and among themselves.

Candida auris undergoes adhesin-dependent and -independent cellular aggregation.

Candida auris is a fungal pathogen of humans responsible for nosocomial infections with high mortality rates. High levels of resistance to antifungal drugs and environmental persistence mean these infections are difficult to treat and eradicate from a healthcare setting. Understanding the life cycle and the genetics of this fungus underpinning clinically relevant traits, such as antifungal resistance and virulence, is of the utmost importance to develop novel treatments and therapies. Epidemiological and genomic studies have identified five geographical clades (I-V), which display phenotypic and genomic differences. Aggregation of cells, a phenotype primarily of clade III strains, has been linked to reduced virulence in some infection models. The aggregation phenotype has thus been associated with conferring an advantage for (skin) colonisation rather than for systemic infection. However, strains with different clade affiliations were compared to infer the effects of different morphologies on virulence. This makes it difficult to distinguish morphology-dependent causes from clade-specific or even strain-specific genetic factors. Here, we identify two different types of aggregation: one induced by antifungal treatment which is a result of a cell separation defect; and a second which is controlled by growth conditions and only occurs in strains with the ability to aggregate. The latter aggregation type depends on an ALS-family adhesin which is differentially expressed during aggregation in an aggregative C. auris strain. Finally, we demonstrate that macrophages cannot clear aggregates, suggesting that aggregation might after all provide a benefit during systemic infection and could facilitate long-term persistence in the host.

PROPERTIES OF CONCRETE AND FIBER-REINFORCED CONCRETE FOR BASES OF ROAD CLOTHES BASED ON SECONDARY AGGREGATES WITH HETEROGENEOUS COMPOSITION

The problem of disposal of concrete scrap of dismantled building structures is relevant for most countries of the world. For Ukraine, this problem is even more acute due to the significant amount of destruction caused by hostilities and rocket attacks. In current research the properties of concrete and fibre-reinforced concrete for the bases of road clothes based on natural and secondary aggregates were compared: granite river gravel, secondary crushed stone with a heterogeneous composition, quartz sand and secondary sand from recycled reinforced concrete structures. CEM III/A slag Portland cement with a blast furnace slag content of 65% and a polycarboxylate type superplasticizer were used. Three series of samples were studied: without fibre; with glass fibre ANTI-CRAK HP 12 (length 12 mm, diameter 0.017 mm, equivalent thread diameter 0.3 mm) in the amount of 1 kg/m3; with polypropylene fibre BeneSteel 55 (length 55 mm, equivalent thread diameter 0.48 mm) in the amount of 4 kg/m3. In each series, concrete on granite gravel and quartz sand, concrete on secondary crushed stone and quartz sand, concrete on secondary crushed stone and secondary sand were studied. The workability of all mixtures was equal to S1. Due to the use of different types of aggregates and fibres, the W/C of concrete mixtures differed significantly. Concretes on secondary aggregates had a higher W/C than on natural aggregates. When using the Anti-Crak HP 12 fibre, the mobility of mixtures with equal W/C increased by 5.5 – 6.9 %. When using BeneSteel 55 fibre, W/C increased by 10.6 – 15.5 %. The type of aggregate had a significant effect on the average density of concrete. When using secondary crushed stone and quartz sand, the average density decreased by 3.8 – 4.6 %. When using secondary crushed stone simultaneously with secondary sand, the average density of concrete decreased by 5.2 – 8.5 %. When using Anti-Crak HP 12 fiber, the average density of concrete decreases by 2 %, when using BeneSteel 55 fibre – up to 4.1 %. Concretes on secondary crushed stone with heterogeneous composition and quartz sand had 4 % higher compressive strength and 2 % higher tensile strength in bending than concretes on granite gravel and similar sand (29.8 MPa and 3.18 MPa, respectively). When secondary crushed stone is used simultaneously with secondary sand, the compressive strength of concrete is only 1.1 % lower than the strength of concrete on natural aggregates, and the tensile strength in bending is 10 % lower. This confirms the possibility of effective use of these concretes for arranging of bases of road clothes. The high-quality performance of secondary aggregates in concrete explains due to their better adhesion to the cement-sand matrix. Dispersed fibre reinforcement with Anti-Crak HP 12 has a positive effect on the compressive strength of concrete on all types of aggregate and increases the tensile strength of concrete on natural aggregates. The use of BeneSteel 55 fibre was not effective due to a significant increase in the W/C of the mixture when it was introduced. In general, taking into account the economic factor, dispersion reinforcement of concrete on secondary aggregates with the types of fibres used in the research is not advisable.

Using tribological approach to assess production temperatures of asphalt binders

In this study, ball on three plates (BOTP) experiment has been used to propose an approach for evaluating the mixing and compaction temperatures of asphalt binder. The results are compared and correlated with equi-viscous- and workability- based methods to arrive at the proposed criterion. A viscosity grade binder, VG30, was modified with varying dosages of Sasobit and Rediset, and the study was executed considering two different types of aggregates (Granite and Dolerite). It was found that warm mix asphalt (WMA) binders can reduce the production temperatures of VG30, irrespective of the test methodology. Equi-viscous method was found to be inappropriate in the quantification of the production temperatures of WMA binders. Workability test results indicated that reduction in mixing and compaction temperatures is a function of the type of warm mix additive, dosages used, and aggregate source. Based on the variability of test parameters in BOTP test, a normal load of “1 N” and a sliding speed of “0.3 m/s” were found to give consistent results of coefficient of friction (CoF). The effect of plate type (Granite, Dolerite, and steel) on the values of CoF was found to be insignificant, and the use of steel plates was recommended. The results of BOTP and workability were in good agreement with each other. Temperature ranges corresponding to the CoF of “0.255–0.282” and “0.317–0.350” are proposed for assessing the mixing and compaction temperatures, respectively.

Prediction model of the mortar’s yield stress based on the aggregate’s volume fraction and properties

Yield stress is an important performance parameter for cement-based materials. Nonetheless, the prediction and regulation of the yield stress using current models still requires the execution of the rheological tests at the corresponding scales (mortar or concrete), which is time-consuming and costly. This paper proposes a model for cement-based materials' (at the mortar scale) yield stress based on theoretical analysis and a multi-scale approach. This model demonstrates that mortar's yield stress can be expressed as a function of the aggregate's properties (specific surface area, volume fraction, size, and packing density) and the yield stress of a cement paste with the same water-to-cement ratio as the mortar. In addition, the model's fitting parameters are fixed for different types of aggregates. Validation tests revealed that the proposed model can accurately predict the mortar's yield stress. Finally, a relationship between relative yield stress and relative plastic viscosity is established, providing useful information for regulating the rheological properties of a given mortar.

The Influence of Different Aggregates on the Physico-Mechanical Performance of Alkali-Activated Geopolymer Composites Produced Using Romanian Fly Ash.

In light of the urgent need to develop environmentally friendly materials that, at some point, will allow the reduction of concrete and, consequently, cement consumption-while at the same time allowing the reuse of waste and industrial by-products-alkali-activated fly ash (AAFA) geopolymer composite emerges as a material of great interest. The aim of this study was to investigate the physico-mechanical performance of composites based on AAFA binders and the effect of different types of aggregates on these properties. The experimental results indicate variations in flexural and compressive strength, which are influenced both by the nature and particle size distribution of aggregates and the binder-to-aggregate ratio. The analysis of the samples highlighted changes in porosity, both in distribution and pore size, depending on the nature of the aggregates. This supports the evolution of physico-mechanical performance indicators.

Preparation and Performance Investigation of Epoxy Resin-Based Permeable Concrete Containing Ceramsite.

Permeable concrete is an innovative type of concrete that provides a sustainable solution for stormwater management by allowing water to seep through and be filtered naturally. This study focuses on the preparation and performance investigation of an epoxy resin-based permeable concrete containing ceramsite. In this study, ceramsite, a lightweight aggregate, is used as a substitute for conventional aggregates in the concrete mixture. The epoxy resin is then added to improve the strength and durability of the concrete. A series of tests, including compressive strength, water permeability, and freeze-thaw resistance tests, are conducted to evaluate the performance of the epoxy resin-based permeable concrete. The results show that with an increasing epoxy resin binder-aggregate ratio, the compressive strength of the epoxy resin-based permeable concrete significantly increases while the permeability coefficient decreases. Different types of aggregates have varying effects on the compressive strength and permeability coefficient of epoxy resin-based permeable concrete, with high-strength clay ceramsite providing the highest compressive strength and lightweight ceramsite having the highest permeability coefficient. In addition, the discrete element simulation method effectively and feasibly determines the ultimate load and accurately simulates the compressive strength of the permeable cement-based mixture, consistent with the measured compressive strength. A quadratic polynomial regression analysis yielded an R2 value of around 0.93, showing a strong relationship between durability and freeze-thaw cycles. The findings contribute to the development of sustainable construction materials for stormwater management and offer potential applications in various infrastructure projects.

Infliximab aggregates produced in severe and mild elevated temperature stress conditions induce an extended specific CD4 T-cell response

Aggregation has been widely described as a factor contributing to therapeutic antibody immunogenicity. Although production of high-affinity anti-drug antibodies depends on the activation of CD4 T lymphocytes, little is known about the T-cell response induced by antibody aggregates, especially for aggregates produced in mild conditions resulting from minor handling errors of vials. Large insoluble infliximab (IFX) aggregates produced in severe elevated temperature stress conditions have been previously shown to induce human monocyte-derived dendritic cell (moDC) maturation. We here showed that large IFX aggregates recruit in vitro a significantly higher number of CD4 T-cells compared to native IFX. Moreover, a larger array of T-cell epitopes encompassing the entire variable regions was evidenced compared to the native antibody. We then compared the responses of moDCs to different types of aggregates generated by submitting IFX to mild conditions of various times of incubation at an elevated temperature. Decreasing stress duration reduced aggregate size and quantity, and subsequently altered moDC activation. Of importance, IFX aggregates generated in mild conditions and not altering moDC phenotype generated an in vitro T-cell response with a higher frequency of CD4 T cells compared to native IFX. Moreover, cross-reactivity studies of aggregate-specific T cells showed that some T cells could recognize both native and aggregated IFX, while others responded only to IFX aggregates. Taken together, our results suggest that aggregation of antibodies in mild elevated temperature stress conditions is sufficient to alter moDC phenotype in a dose-dependent manner and to increase T-cell response.

Toward the flow-centric detection of browser fingerprinting

Browser fingerprinting has become a prevalent technique employed by websites for advertising and analytics. It utilizes JavaScript objects and APIs to gather traditional and non-traditional browser attributes and creates unique identifiers for online user tracking. While previous research has examined the invocation of the browser's built-in JavaScript objects and APIs to retrieve browser attribute values, it overlooks the use and flow of those values within scripts.In this paper, we define browser fingerprinting behavior as the aggregation of different types of browser attributes, and reduce the detection of browser fingerprinting to a joint analysis of the data flows of browser attribute values in JavaScript code. FProbe, our proposed framework for the flow-centric detection of browser fingerprinting, performs context-sensitive static data flow analysis on JavaScript code. Given the complexity and dynamic features of the JavaScript language, achieving soundness in static analysis of JavaScript code is extremely challenging or even impossible. Consequently, FProbe aims to be a practical and accurate tool for detecting browser fingerprinting. We implemented FProbe in Java and evaluated its performance using 4,296 fingerprinting scripts from recent work and 2,335,317 pieces of JavaScript code on 988,220 websites. FProbe achieved F-measures of 97.81% and 96.31% on these datasets, respectively. It identified browser fingerprinting behavior on 0.78% of the 988,220 websites, with the use of the toDataURL method observed in 4.26% of the fingerprinting scripts. Notably, only 72 fingerprinting scripts and 10 fingerprinting providers identified by FProbe were reported in previous work. These results highlight the effectiveness of FProbe in detecting browser fingerprinting and its complementarity to existing detection tools. Additionally, our comprehensive study demonstrates that fingerprinting with traditional browser attributes can achieve a 96.6% F-measure.

α-Synuclein Drives Tau's Cytotoxic Aggregates Formation through Hydrophobic Interactions.

Tau and α-synuclein are proteins involved in pathologies known as tauopathies and synucleinopathies, respectively. Moreover, evidence shows that there is a crosstalk between them as is seen in the brains of individuals with sporadic neurodegenerative disorders. Based on that, we present data showing that the hydrophobic α-peptide 71 VTGVTAVAQKTV82 induces the aggregation of the full-length tau fragment in the absence of heparin assessed by ThT. Moreover, AFM images reveal the presence of straight filaments and amorphous aggregates of full-length tau in the presence of the α-peptide. Additionally, ITC experiments showed the interaction of the α-peptide with tau full-length (441 amino acids),4R (amino acids from 244 to 369), and both hexapeptides 275 VQIINK280 and 306 VQIVYK311 through hydrophobic interactions. The Raman spectroscopy spectra showed conformational changes in the Amide region in the aggregates formed with full-length tau and α-syn peptide. Furthermore, the incubation of extracellular aggregates with N2a cells showed morphological differences in the cellular body and the nucleus suggesting cell death. Moreover,, the incubation of different types of aggregates in cell culture provokes the release of Lactate dehydrogenase (LDH). Altogether, we found that α-synuclein peptide can drive the aggregation of full-length tau-provoking morphological and structural changes evoking cytotoxic effects.

Impact of internal structure on aggregate collisions

ABSTRACT Granular-mechanics simulations are used to study collisions between granular aggregates. We compare the collision outcomes for three different types of aggregate: (i) aggregates constructed by a ballistic particle–cluster aggregation (BPCA) process, and two homogeneous spherical aggregates which differ by their grain coordination. All aggregates contain the same number of grains and (central) filling factor. We find that BPCA aggregates have a slightly decreased growth velocity for central impacts. After scaling the collision velocities to the growth velocity for central impact and the impact parameter to the gyration radius, our collision results show a remarkable degree of agreement for the aggregates studied. Also, the collision-induced compaction as well as the size of fluctuations during the collision process are identical for all aggregate types. Even at glancing collisions, the larger extension and rough surface of BPCA aggregates do not cause major changes as compared to homogeneous aggregates with a well-defined and smooth surface. However, monomer ejection during the collision is enhanced for BPCA aggregates. This study thus shows that details of the internal aggregate structure are of little importance in collisions of granular aggregates, except for grain ejection.

Renewable Energy Community with distributed storage optimization to provide energy sharing and additional ancillary services

Renewable energy community represents a new market paradigm adopted to increase the penetration of distributed renewable energy sources and to value the flexibility potentials of customers in presence of behind the meter storage system. Different types of storage systems allow to manage power on different time scale from seconds time basis, f.i. battery, to month, f.i. hydrogen. For this reason, the aggregation of different types of distributed small-scale storage systems may be the solution to maximize the self-consumption of the community and to deliver appropriate ancillary services to the power system. In this context, the paper proposes a day-ahead optimization model for the management of a local energy distributed storage community in order to provide self-consumption benefits and ancillary services to the power system. A detailed analysis with simulation results on a relevant real-life test case are reported and discussed in details.