Intermediate Process Research Articles

A social reproduction analysis of digital care platform work

ABSTRACT Digital platforms are becoming an important factor in the process of reconfiguration and commodification of social reproduction during the neoliberal phase of capitalism. Developing a theoretical framework merging social reproduction theory and migrant labour regimes, this article argues that the introduction of digital platforms in the care sector is facilitating the expansion of precarised commodification of reproductive activities in a context of social care crisis. Through a mixed-method analysis, combining desk-based research with in-depth interviews of digital care platform work in Spain, the study examines the migrant labour regime of digital care platforms and how they take advantage of the international division of labour and global care chains to further exploit a highly precarious, informalised, feminised and racialised workforce. Our findings reveal that platforms use technology to rapidly access a reserve labour army, thus extracting more surplus value by restricting access to information, controlling the intermediation process and further fragmenting the workforce in reproductive activities.

Synthesis and characterization of hierarchical suspended carbon fiber structures decorated with carbon nanotubes

Carbon nanotubes (CNTs) and carbon microfibers (CMFs) have received significant attention due to their exceptional mechanical and electrical properties, which make them promising materials for various applications. This study introduces a novel approach to integrate CNTs and CMFs into a unified architecture by simultaneously conducting pyrolysis and chemical vapor deposition (CVD). The localized CVD of CNTs on suspended CMFs was achieved by utilizing Fe–Co nanoparticles (NPs) embedded in polyacrylonitrile (PAN) fibers as catalysts. Scanning electron microscopy and elemental analysis confirmed the formation of needle-like carbon structures on the pyrolyzed fiber surface, where carbon gases released from the pyrolyzing PAN fiber acted as the carbon source for the localized CVD. The incorporation of an additional carbon source, such as camphor vapor, significantly enhanced the growth and density of CNTs on the CMF. Various characterization techniques, including transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and Atomic Force Microscopy, were employed to analyse the properties of the synthesized materials. The substantial increase in electrical conductivity upon incorporating CNTs highlights their positive influence on electrical properties and defect reduction. These characterization results highlight the potential applications of the fabricated structures in various fields, including sensors, lithium-ion electrodes, and microfabrication. In addition, the economic advantages of optimizing the process by integrating CVD with pyrolysis were assessed, revealing decreased operation time, lower energy consumption, and reduced chemical costs in comparison to conventional methods involving multiple intermediate processing steps.Graphical

Thallium-208: A Beacon of InSitu Neutron Capture Nucleosynthesis.

We demonstrate that the well-known 2.6MeV gamma-ray emission line from thallium-208 could serve as a real-time indicator of astrophysical heavy element production, with both rapid (r) and intermediate (i) neutron capture processes capable of its synthesis. We consider the r process in a Galactic neutron star merger and show Tl-208 to be detectable from ∼12 hours to ∼ten days, and again ∼1-20 years postevent. Detection of Tl-208 represents the only identified prospect for a direct signal of lead production (implying gold synthesis), arguing for the importance of future MeV telescope missions which aim to detect Galactic events but may also be able to reach some nearby galaxies in the Local Group.

Purification of Saccharomyces cerevisiae recombinant Crp1

A complex Mus81-Mm4 is a DNA structure–specific endonuclease in Saccharomyces cerevisiae. Mus81-Mms4 functions in processing of recombination intermediates that could arise during the repair of stalled and blocked replication forks and double stranded breaks. Mus81-Mms4 works with many proteins involved in DNA repair, replication fork stability, and joint molecule formation/resolution during homologous recombination repair. A biochemical screening of protein(s) that enhances the Mus81-Mms4 endonuclease activity on its preferable substrates in vitro revealed that Crp1, a cruciform DNA-recognizing protein, which can specifically bind to DNA four-way junction structures like Holliday junctions could be the potential factor. To further demonstrate that Crp1 interacts functionally with Mus81-Mms4 in vitro, we carried out the purification of recombinant Crp1 using Escherichia coli system. Our results showed that the purified Crp1 was highly homogenous and active that is ready for biochemical use.

Coupling of CO2 Electrolysis with Parallel and Semi-Automated Biopolymer Synthesis - Ex-Cell and without Downstream Processing.

Important improvements have been achieved in developing the coupling of electrochemical CO2 reduction to formate with its subsequent microbial conversion to polyhydroxybutyrate (PHB) by Cupriavidus necator. The CO2 based formate electrosynthesis was optimised by electrolysis parameter adjustment and application of Sn based gas diffusion electrodes reaching almost 80 % Faradaic efficiency at 150 mA cm-2. Thereby, catholyte with the high formate concentration of 441±9 mmol L-1 was generated as feedstock without intermediate downstream processing for semi-automated formate feeding into a fed-batch reactor system. Moreover, microbial formate conversion to PHB was studied further, optimised, and successfully scaled from shake flasks to semi-automated bioreactors. Therein, a PHB per formate ratio of 16.5±4.0 mg g-1 and a PHB synthesis rate of 8.4±2.1 mg L-1 OD-1 h-1 were achieved. By this process combination, an almost doubled overall process yield of 22.3±5.5 % was achieved compared to previous reports. The findings allow a detailed evaluation of the overall CO2 to PHB conversion, providing the basis for potential technical exploitation.

Tungsten in barium stars

Abstract Classical barium stars are red giants that received from their evolved binary companions material exposed to the slow neutron-capture nucleosynthesis, i.e., the s-process. Such a mechanism is expected to have taken place in the interiors of Thermally-Pulsing Asymptotic Giant Branch (TP-AGB) stars. As post-interacting binaries, barium stars figure as powerful tracers of the s-process nucleosynthesis, evolution of binary systems, and mechanisms of mass transfer. The present study is the fourth in a series of high-resolution spectroscopic analyses on a sample of 180 barium stars, for which we report tungsten (W, Z = 74) abundances. The abundances were derived from synthetic spectrum computations of the W i absorption features at 4843.8 Å and 5224.7 Å. We were able to extract abundances for 94 stars; the measured [W/Fe] ratios range from ∼0.0 to 2.0 dex, increasing with decreasing of metallicity. We noticed that in the plane [W/Fe] versus [s/Fe] barium stars follow the same trend observed in post-AGB stars. The observational data were also compared with predictions of the fruity and Monash AGB nucleosynthesis models. These expect values between −0.20 and +0.10 dex for the [W/hs] ratios, whereas a larger spread is observed in the program stars, with [W/hs] ranging from −0.40 to +0.60 dex. The stars with high [W/hs] ratios may represent evidence for the operation of the intermediate neuron-capture process at metallicities close to solar.

Boosting Nitrate to Ammonia via the Optimization of Key Intermediate Processes by Low‐Coordinated Cu–Cu Sites

AbstractThe electrochemical reduction of nitrate to ammonia (NO3RR) has emerged as a promising but challenging orientation in sustainable development. Cu is one of the most effective NO3RR catalysts. However, the accumulation of NO2− on their surface has erected bars to the further improvement of NO3RR efficiency. Herein, Cu‐based electrocatalyst with low‐coordinated Cu atoms (Cu‐LC) is synthesized via the instantaneous ablation and rapid cooling of the Cu target by pulse laser and proposed as a new NO3RR electrocatalyst, which exhibits enhanced NO3RR activity with NH3 selectivity of 97.01%, yield rate of 0.624 mmol h−1 cm−2 at −0.8 V versus RHE and long‐term durability, superior to most reported Cu‐based catalysts. The introduction of low‐coordinated Cu sites upshifts the Cu d‐band center to near the Fermi Level, enhancing the adsorption of key intermediates (*NO2, *NO) in NO3RR, and also effectively regulating the generation of *NO2 and hydrogenation process, inhibiting the accumulation of NO2− on the Cu‐LC surface, thus achieving efficient NH3 production. Furthermore, when evaluated as cathode material in Zn–NO3− battery, an open circuit voltage of 1.3 V and a power density of 3.1 mW cm−2 are achieved by the Cu‐LC‐based battery, highlighting a promising multifunctional system for ammonia production and energy supply.

A novel data-driven sensor placement optimization method for unsupervised damage detection using noise-assisted neural networks with attention mechanism

Optimization of sensor placement (OSP) is one of the important steps in structural health monitoring to reduce the instrumentation cost, and improve damage detection. Although modal analysis is an optional intermediate process in terms of damage detection, conventional OSP methods for damage detection are mostly dependent on mode shapes. In this case, the sensor placement and damage detection are highly relying on the accuracy of modal analysis, and the results may not be adapted to different type of excitations. In this article, a novel noise-assisted neural network with attention mechanism is proposed based on the above challenges. This method which can be used to optimize sensor placement in an unsupervised and data-driven manner, is verified using a dataset simulated from the ASCE benchmark and an experimental dataset obtained from shake table tests. The results from the simulated dataset show that the percentage of the sensors that could be removed are higher than the conventional effective independence (EFI) method, with a highest of 62.5% for cases with low noise levels. In the meantime, the occurrence and the level of damage can still be well detected with a reduced number of sensors. Most importantly, in the proposed approach the optimal sensor placement configurations can be determined adaptively to account for different forms of excitations and noise levels, which is impossible for conventional model-driven methods. The results obtained from the experimental dataset show that the proposed method is also effective for real-world applications. As a result, the proposed data-driven OSP method skips the conventional model analysis process and directly focuses on the sensor arrangement that enables accurate detection of damage. It also has the potential for application in related fields, such as the monitoring of aerospace and mechanical infrastructures.

Comparing the mechanisms of syntrophic volatile fatty acids oxidation and methanogenesis recovery from ammonia stress in regular and biochar-assisted anaerobic digestion: Different roads lead to the same goal

Biochar has been recognized as a promising additive to mitigate ammonia inhibition during syntrophic methanogenesis, while the key function of biochar in this process is still in debates. This study clarified the distinct mechanisms of syntrophic volatile fatty acids -oxidizing and methanogenesis recovery from ammonia inhibition in regular and biochar-assisted anaerobic digestion. Under 5 g/L ammonia stress, adding biochar shortened the methanogenic lag time by 10.9% and dramatically accelerated the maximum methane production rate from 60.3 to 94.7 mLCH4/gVSsludge/d. A photometric analysis with a nano-WO3 probe revealed that biochar enhanced the extracellular electron transfer (EET) capacity of suspended microbes (Pearson's r = −0.98), confirming that biochar facilitated methanogenesis by boosting EET between syntrophic butyrate oxidizer and methanogens. Same linear relationship between EET capacity and methanogenic rate was not observed in the control group. Microbial community integrating functional genes prediction analysis uncovered that biochar re-shaped syntrophic partners by enriching Constridium_sensu_stricto/Syntrophomonas and Methanosarcina. The functional genes encoding Co-enzyme F420 hydrogenase and formylmethanofuran dehydrogenase were upregulated by 1.4–2.3 times, consequently enhanced the CO2-reduction methanogenesis pathway. Meanwhile, the abundances of gene encoding methylene-tetrahydrofolate transformation, a series of intermediate processes involved in acetate oxidation, in the biochar-assisted group were 28.2–63.7% higher than these in control group. Comparatively, Methanosaeta played a pivotal role driving aceticlastic methanogenesis in the control group because the abundance of gene encoding acetyl-CoA decarbonylase/synthase complex increased by 1.9 times, suggesting an aceticlastic combining H2-based syntrophic methanogenesis pathway was established in control group to resist ammonia stress. A 2nd period experiment elucidated that although depending on distinct mechanisms, the volatile fatty acid oxidizers and methanogens in both groups developed sustained and stable strategies to resist ammonia stress. These findings provided new insights to understand the distinct methanogenic recovery strategy to resist toxic stress under varied environmental conditions.

Soil freeze–thaw cycles affect spring phenology by changing phenological sensitivity in the Northern Hemisphere

The use of frozen soil-vegetation feedback for predictive models is undergoing enormous changes under rapid climate warming. However, the influence of soil freeze–thaw (SFT) cycles on vegetation phenology and the underlying mechanisms remain poorly understood. By synthesizing a variety of satellite-derived data from 2002 to 2021 in the Northern Hemisphere (NH), we demonstrated a widespread positive correlation between soil thawing and the start of the growing season (SOS). Our results also showed that the SFT cycles had a significant impact on vegetation phenology mainly by altering the phenological sensitivities to daytime and nighttime temperatures, solar radiation and precipitation. Moreover, the effects of SFT cycles on the sensitivity of the SOS were more pronounced than those on the sensitivity of the end of the growing season (EOS) and the length of growing season (LOS). Furthermore, due to the degradation of frozen soil, the changes in phenological sensitivity in the grassland and tundra biomes were significantly larger than those in the forest. These findings highlighted the importance of incorporating the SFT as an intermediate process into process-based phenological models.

Light and electron microscopic observations on retinal neurons of red-tail shark (Epalzeorhynchos bicolor H. M. Smith, 1931).

The structure of photoreceptors (PR) and the arrangement of neurons in the retina of red-tail shark were investigated using light and electron microscopy. The PR showed a mosaic arrangement and included double cones, single cones (SC), and single rods. Most cones occur as SC. The ratio between the number of cones and rods was 3:1.39 (±0.29). The rods were tall that reached the pigmented epithelium. The outer plexiform layer (OPL) showed a complex synaptic connection between the horizontal and photoreceptor terminals that were surrounded by Müller cell processes. Electron microscopy showed that the OPL possessed both cone pedicles and rod spherules. Each rod spherule consisted of a single synaptic ribbon within the invaginating terminal endings of the horizontal cell (hc) processes. In contrast, the cone pedicles possessed many synaptic ribbons within their junctional complexes. The inner nuclear layer consisted of bipolar, amacrine, Müller cells, and hc. Müller cells possessed intermediate filaments and cell processes that can reach the outer limiting membrane and form connections with each other by desmosomes. The ganglion cells were large multipolar cells with a spherical nucleus and Nissl' bodies in their cytoplasm. The presence of different types of cones arranged in a mosaic pattern in the retina of this species favors the spatial resolution of visual objects. RESEARCH HIGHLIGHTS: This is the first study demonstrating the structure and arrangement of retinal neurons of red-tail shark using light and electron microscopy. The current study showed the presence of different types of cones arranged in a mosaic pattern that may favor the spatial resolution of visual objects in this species. The bipolar, amacrine, Müller, and horizontal cells could be demonstrated.

Fully Composable and Adequate Verified Compilation with Direct Refinements between Open Modules

Verified compilation of open modules (i.e., modules whose functionality depends on other modules) provides a foundation for end-to-end verification of modular programs ubiquitous in contemporary software. However, despite intensive investigation in this topic for decades,the proposed approaches are still difficult to use in practice as they rely on assumptions about the internal working of compilers which make it difficult for external users to apply the verification results. We propose an approach to verified compositional compilation without such assumptions in the setting of verifying compilation of heterogeneous modules written in first-order languages supporting global memory and pointers. Our approach is based on the memory model of CompCert and a new discovery that a Kripke relation with a notion of memory protection can serve as a uniform and composable semantic interface for the compiler passes. By absorbing the rely-guarantee conditions on memory evolution for all compiler passes into this Kripke Memory Relation and by piggybacking requirements on compiler optimizations onto it, we get compositional correctness theorems for realistic optimizing compilers as refinements that directly relate native semantics of open modules and that are ignorant of intermediate compilation processes. Such direct refinements support all the compositionality and adequacy properties essential for verified compilation of open modules. We have applied this approach to the full compilation chain of CompCert with its Clight source language and demonstrated that our compiler correctness theorem is open to composition and intuitive to use with reduced verification complexity through end-to-end verification of non-trivial heterogeneous modules that may freely invoke each other (e.g.,mutually recursively).

Highly efficient isomerization of glucose to fructose over Sn-doped silica nanotube

Isomerization of glucose to fructose is a fundamental and key intermediate process commonly included in the production of valuable chemicals from carbohydrates in biorefinery. Enhancement of fructose yield is a challenge. In this work, Sn-doped silica nanotube (Sn-SNT) was developed as a highly efficient Lewis acid catalyst for the selective isomerization of glucose to fructose. Over Sn-SNT, 69.1 % fructose yield with 78.5 % selectivity was obtained after reaction at 110 °C for 6 h. The sole presence of a large amount of Lewis acid sites in Sn-SNT without Brønsted acid site is one of the reasons for the high fructose yield and selectivity. Otherwise, high density of Si−OH groups in Sn-SNT can ensure the presence of Si−OH groups near the Sn sites, which is important for the isomerization of glucose to fructose, leading to the high fructose yield and selectivity. Furthermore, the Sn-SNT is recyclable.

Imparting high elastocaloric cooling potential to NiTi alloy by two-step enhancements

The large adiabatic temperature change during the stress-induced phase transformation in the superelastic NiTi alloy makes it a leading candidate material for solid-state elastocaloric cooling applications. However, NiTi with a uniform grain structure generally offers either large cooling capacity or low energy dissipation, but not both. In an earlier study, we demonstrated that the alloy with graded grain sizes, obtained using differential annealing of heavily cold-worked sheets, can overcome this intrinsic limitation. However, non-transformable components (residual martensite and amorphous phases), which are introduced into the microstructure during cold rolling, impair the full exploitation of the cooling potential of the graded NiTi. Here, we introduce an intermediate processing step, namely post-deformation annealing, which eliminates the undesirable phases while maintaining nanocrystallinity, before imparting a microstructural gradient. Results show that the synergy between various microstructural elements results in a significant enhancement in the cooling capacity while keeping the energy dissipation low. Moreover, the functional fatigue performance of the graded alloy is also preferable to that of the conventional coarse-grained NiTi. The micromechanical reasons behind these improvements are elucidated by recourse to detailed experiments.

Le processus d’intermédiation comme levier de l’innovation sociale

Intermediation plays an essential - but little studied - role in the dissemination of social innovation (SI). In this article, we seek to understand how the process of intermediation in social innovation is constructed and what its effects are. We combine the actor network and creative ecology theories to explore the practices and dynamics at work in the case of the Start-Up de Territoire (SUT) programme. We show that the intermediary function is gradually structured over time, and we identify 4 intermediation processes of SI that condition the transition to scale: building the vision of the territory, expanding the network, bringing out the middleground, and articulating the different levels by distinguishing between top-down and bottom-up translation.

Digital Twin‐Enabled Delay Diagnosis Traceability and Propagation Process for Airport Flight Ground Service

The emergence of digital twin technology offers a promising solution to address the limitations of traditional methods on early diagnosis and accurate propagation analysis of flight ground service delays. However, the application of digital twin technology in the civil aviation domain still stays at the lower maturity of the L2 level, which focuses on physical assets, operational data, and maintenance planning at airports, and failed to achieve the integration of flight ground operation mechanism and real‐time data, making it difficult to realize timely delay diagnosis. The simulation model is also limited to the offline simulation technology, which cannot connect to real‐time data for simulation from intermediate processes. In this work, we developed an advanced L3‐level airport digital twin system for flight ground service processes delay diagnosis and propagation, which focused on real‐time data‐driven simulation models and machine learning applications to meet the timely and precision requirements. First, we used the Unity3D platform to construct static three‐dimensional models of flight ground service objects on the airport cloud server. By parsing these behavioral state interfaces and mapping real‐time dynamic data from the airport sensing and business systems, we achieved accurate visualization of the airport’s dynamic operational processes. Then, a vehicle delay tree–based Bayesian diagnostic model was proposed in the digital twin system to analyze the relationships between multiple flights and service processes, which enables proactive diagnosis of the operation status and provides delay warning information. To improve the accuracy of propagation analysis, we proposed a “breakpoint” simulation method that enables real‐time simulation starting from an intermediate moment, facilitating the inference of flight ground service delays since the early warning moment. In addition, two delay tracing and propagation algorithms were proposed to identify delays and investigate propagation paths. Leveraging real‐time operational information, our approach provides valuable feedback for decision‐making, empowering the airport manager to formulate precise optimization strategies. Experiments on real‐world airport data have validated the effectiveness of our proposed method and provided practical recommendations for airport managers to reduce aircraft delays and improve airport operation efficiency.

Study of the Astrophysical Origins of Neutron-captue Elements in CEMP Star HE 1005-1439

HE 1005-1439 is a carbon-enhanced metal-poor (CEMP) star with [Fe/H]∼−3.0, which is largely enhanced in elements produced by slow neutron-capture process (s-process; e.g., [Ba/Fe]=1.16±0.31, [Pb/Fe]=1.98±0.19), and mildly enhanced in elements produced by rapid neutron-capture process (r-process; e.g., [Eu/Fe]=0.46±0.22). The neutron-capture element patterns of the star can not be fitted by the s-process model or intermediate process (i-process) model. Studying the astrophysical origins of chemical elements in the star based on the method of abundance decomposition can help understanding the formation and evolution of the CEMP stars. Using the combination of s-process and r-process abundances, we fully fit the abundance patterns of the neutron-capture elements of this star. We find that the neutron-capture elements are mainly produced by the s-process of the AGB companion with low mass and low metallicity, and the r-process nucleosynthesis also contributes a little to this star.

A multi-functional high-dynamic intermediate frequency signal acquisition and processing module

A multi-functional high-dynamic intermediate frequency signal acquisition and processing module

Collaborative Governance Process by Disaster Resilient Villages (DESTANA) to Improve Performance

The existence of a Disaster Resilient Village (Destana) is very important for the region in mitigating flood disasters. Destana has the function of protecting the community, increasing community participation, increasing capacity, increasing government capacity in providing resource and technical support for disaster risk reduction, and increasing cooperation between stakeholders. This function will be achieved well if there is collaboration with other stakeholders. Destana's performance will be better if it can create collaborative governance through the right process. The process begins with face-to-face, namely conducting dialogue on existing problems with stakeholders. Followed by a trust-building process, namely creating a sense of trust because of shared interests, after that, the commitment to the process is a joint agreement to carry out the program. The next process is sharing understanding, which is raising awareness together to overcome floods followed by the Intermediate outcomes process, which is evaluating the temporary results of the collaborative process. These steps will be able to run optimally to improve Destana's performance if the right organization is selected to collaborate with so that a scheme is needed that fits the conditions of each village.

Quality Improvement Effect of Waste Concrete Fine Powder by Applying Exfoliation Technology

Since the main components of waste concrete fine powder generated in the process of converting waste concrete into recycled aggregate are essentially the same as the main ingredients of cement-clinker, it is possible to use it as a raw material for cement. In addition, because waste concrete fine powder is a decarbonated salt, using it as a raw material for cement clinker is a very important carbon-neutral technology that can be expected to reduce process-derived carbon emission generated during cement manufacturing. However, waste concrete fine powder has a low calcium oxide content of around 10%, so its usability as a clinker raw material is very low. In order to use waste concrete fine powder as a raw material for clinker, the calcium oxide content must be increased to more than 35%. Separating the hardened cement paste from the aggregate while reducing the crushing ration of the aggregate during the crushing process is an important means of increasing the calcium oxide content of waste concrete fine powder. Accordingly, this study conducted an experimental study to increase the calcium oxide content of waste concrete fine powder using exfoliation grinding technology. The characteristics of waste concrete fine powder recovered through the exfoliation grinding technology were examined for waste concrete collected from a domestic intermediate processing company, model concrete manufactured in a laboratory, and commercially available cement bricks. As a result of the experiment, it was possible to recover the waste concrete fine powder with a higher CaO content by applying exfoliation grinding technology, compared to the dust collection fine powder that could be recovered through the crushing and grinding process.