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Cold metal transfer (CMT)-based wire-arc additive manufacturing (WAAM) is a promising method for the production of large-scale and complex metallic parts because of its high efficiency, less heat input and low cost. However, a critical and common problem with the arc welding processes is the irregular geometry at the beginning and end parts of the bead due to the ignition and extinction of the arc. Based on experimental investigations of the irregularities and different possible optimization methods, an improvement strategy consisting of configurations with a varying travel speed and an extra return path is presented in this paper. Experimental results show that this strategy can effectively enhance the geometric accuracy at the beginning and end parts of different single beads. In the manufacturing of a thin-wall part and a multi-pass cladding, the improvement of geometric accuracy has also been achieved by this strategy.

Demand is strong for sensitive, reliable, and cost-effective diagnostic tools for cancer detection. Accordingly, bead-based biosensors have emerged in recent years as promising diagnostic platforms based on wide-ranging cancer biomarkers owing to the versatility, high sensitivity, and flexibility to perform the multiplexing of beads. This comprehensive review highlights recent trends and innovations in the development of bead-based biosensors for cancer-biomarker detection. We introduce various types of bead-based biosensors such as optical, electrochemical, and magnetic biosensors, along with their respective advantages and limitations. Moreover, the review summarizes the latest advancements, including fabrication techniques, signal-amplification strategies, and integration with microfluidics and nanotechnology. Additionally, the challenges and future perspectives in the field of bead-based biosensors for cancer-biomarker detection are discussed. Understanding these innovations in bead-based biosensors can greatly contribute to improvements in cancer diagnostics, thereby facilitating early detection and personalized treatments.

The conventional planar culture of adherent cells is inefficient for large‐scale manufacturing of cell and gene therapy products. We developed a facile and efficient bead‐to‐bead cell‐transfer method for serial subculture and large‐scale expansion of human mesenchymal stem cells (hMSCs) with microcarriers in bioreactors. We first compared culture medium with and without nucleosides and found the former maintained the expression of surface markers of hMSCs during their prolonged culture and enabled faster cell proliferation. Subsequently, we developed our bead‐to‐bead cell transfer method to subculture hMSCs and found that intermittent agitation after adding fresh microcarriers to cell‐populated microcarriers could promote spontaneous cell migration to fresh microcarriers, reduce microcarrier aggregation, and improve cell yield. This method enabled serial subculture of hMSCs in spinner flasks from passage 4 to passage 9 without using proteolytic enzymes, which showed faster cell proliferation than the serial planar cultures undergoing multiple enzyme treatment. Finally, we used the medium containing nucleosides and our bead‐to‐bead cell transfer method for cell culture scale‐up from 4‐ to 50‐L cultures in single‐use bioreactors. We achieved a 242‐fold increase in the number of cells to 1.45 × 1010 after 27‐day culture and found that the cells harvested from the bioreactors maintained proliferation ability, expression of their surface markers, tri‐lineage differentiation potential and immunomodulatory property. This study shows the promotive effect of nucleosides on hMSC expansion and the potential of using our bead‐to‐bead transfer method for larger‐scale manufacturing of hMSCs for cell therapy. The expansion of human mesenchymal stem cells (hMSCs) was promoted using a culture medium with nucleosides. Intermittent agitation was performed to facilitate bead‐to‐bead cell transfer to expand hMSCs in bioreactors without proteolytic enzymes. By using this culture medium and our bead‐to‐bead cell‐transfer method, hMSC cultures were scaled up from 4‐ to 50‐L in bioreactors, resulting in a 242‐fold increase in cell number to 1.45 × 1010.

Wire arc additive manufacturing (WAAM) has emerged as a promising technology for producing complex, large-scale components with high material deposition rates, reduced waste, and shorter lead times. This study focused on optimizing process parameters in cold metal transfer (CMT)-based WAAM to achieve superior bead geometry and enhanced microhardness in stainless steel 321. Welding current, travel speed, and shielding gas mixture ratio were selected as input parameters, whereas bead width, depth of penetration, diffusion area, and microhardness were the response variables. Using response surface methodology (RSM) with a central composite design, a regression model was developed to identify optimal process parameters. The optimal parameters are 150 A current, 4-5 mm/s travel speed, and 0-10% CO2 shielding gas, which produced favorable bead geometry and a microhardness of 180 HV, validating the RSM model’s predictive accuracy. Experimental validation confirmed the model’s accuracy in producing high-quality SS321 structures. Tensile testing validated mechanical performance, with yield strength 372.07-384.46 MPa, ultimate tensile strength (UTS) 590.19-598.96 MPa, and elongation 38% (90°) and 41% (0°), surpassing ASTM A240/A240M-20a standards. Scanning electron microscopy fractography revealed ductile failure with micro-voids and fine dimples, confirming a ductile mode of mechanical behavior. These findings demonstrate the reliability of RSM in optimizing CMT-WAAM processes and additive manufacturing applications.

Large-scale photochemical synthesis of high value chemicals under mild conditions is an ideal method of green chemical production. However, a scalable photocatalytic process has been barely reported due to the costly preparation, low stability of photosensitizers and critical reaction conditions required for classical photocatalysts. Here, we report the merging of flow chemistry with heterogeneous photoredox catalysis for the facile production of high value compounds in a continuous flow reactor with visible light at room temperature in air. In the flow reactor system, polymeric carbon nitrides, which are cheap, sustainable and stable heterogeneous photocatalysts, are immobilized onto glass beads and fibers, demonstrating a highly flexible construction possibility for devices of the photocatalytic materials. As an example of the production of high value chemicals, important chemical structures such as cyclobutanes, which are basic building blocks for many pharmaceutical compounds, like magnosalin, are synthesized in flow with high catalytic efficiency and stability. Large-scale photochemical synthesis of high value chemicals is an ideal method of green chemical production. Here, the authors show the merging of heterogeneous carbon nitride photocatalysis with flow chemistry for the scalable organosynthesis of fine chemicals in a continuous flow reactor.

Hunter-gatherer exchange networks dampen subsistence and reproductive risks by building relationships of mutual support outside local groups that are underwritten by symbolic gift exchange. Hxaro, the system of delayed reciprocity between Ju/’hoãn individuals in southern Africa’s Kalahari Desert, is the best-known such example and the basis for most analogies and models of hunter-gatherer exchange in prehistory. However, its antiquity, drivers, and development remain unclear, as they do for long-distance exchanges among African foragers more broadly. Here we show through strontium isotope analyses of ostrich eggshell beads from highland Lesotho, and associated strontium isoscape development, that such practices stretch back into the late Middle Stone Age. We argue that these exchange items originated beyond the macroband from groups occupying the more water-stressed subcontinental interior. Tracking the emergence and persistence of macroscale, transbiome social networks helps illuminate the evolution of social strategies needed to thrive in stochastic environments, strategies that in our case study show persistence over more than 33,000 y.

Culturomics employs various cultivating conditions to obtain different types of bacteria and new species. However, current culturomics lacks a highly efficient method for isolating specific pathobionts. Immunomagnetic bead technology, which uses magnetic beads conjugated with antibodies for capturing the antigen to realize enrichment of the targets, has been employed as an alternative method. In this study, we developed a novel method, immunomagnetic bead‐enriched culturomics (IMBEC), in which magnetic bead‐conjugated antibodies purified from the fecal samples of patients with colorectal cancer (CRC) were used to enrich and isolate potential pathobionts. A protocol for enriching potential pathobionts via immunomagnetic capture was developed by optimizing the concentrations of coupling reagents, NaCl, and detergent. The efficacy of pathobiont enrichment was compared between antibody‐coated magnetic beads (antibody group) and nonconjugated blank magnetic beads (blank group). To determine the proinflammatory potential of isolates from both groups, we investigated their ability to induce cytokine production in THP‐1 macrophages. This protocol was employed for isolating bacteria from 10 fecal samples of patients with CRC, which were simultaneously compared with those isolated from the blank group. A total of 209 bacterial species were isolated from both groups, including 173 from the antibody group, 160 from the blank group, and 124 from both groups. Bacteria isolated from the antibody group produced more proinflammatory cytokines than those isolated from the blank group. IMBEC is a promising method for relatively specific isolation of potential pathobionts for a particular disease of interest. We developed a novel method, immunomagnetic bead‐enriched culturomics (IMBEC), which can obtain potential pathobionts from the precultivated colorectal cancer (CRC) fecal samples. We optimized the IMBEC process from the perspective of coupling reagents and magnetic beads washing lotion. Not only in CRC but it has also been reported that antibodies produced by pathobiont strains exist in the blood of patients with other diseases, so the method of precise isolation of disease‐related strains by IMBEC is expected to be a powerful method to accurately isolate pathobiont strains. Highlights We have developed a novel method called immunomagnetic bead‐enriched culturomics (IMBEC) to enrich and isolate colorectal cancer‐related pathobionts. This method combines immunomagnetic beads and culturomics technology. IMBEC can be targeted to isolate more bacterial species associated with cancer or inflammation, and can be accurate to the strain level. Bacterial DNA is not only detected in the blood of colorectal cancer patients but also in the serum of patients with other diseases, so IMBEC can also be employed in other diseases to isolate pathobionts.

Weld bead measurement and weld quality inspection are important parts in industrial welding. In this paper, a structured light vision sensor is developed to achieve on-line weld bead measurement and weld quality inspection. Firstly, a structured light vision sensor with a narrow-band optical filter is developed to reduce welding noises such as arc lights and splashes. Secondly, the weld bead type identification algorithm including image pre-processing, baseline extraction, and weld bead classification is proposed to classify filling weld bead and capping weld bead. Thirdly, feature extraction algorithms of filling weld bead and capping weld bead are presented to obtain corresponding feature points. Combining the image coordinates of feature points with structured light vision model, the weld bead size could be obtained and the weld quality could be evaluated. Finally, many weld bead measurement and weld quality inspection experiments are conducted. Experimental results demonstrate that the developed structured light vision sensor and proposed methods could achieve satisfactory performance for weld quality inspection.

The multi-component site of Phromtin Tai, Thailand is notable for its long occupation from the Late Bronze Age (ca. 700–500 b.c.e.) through early historic periods (ca. c.e. 500–900). Multiple field seasons of excavation in burial and habitation areas at the site have recovered a large number of glass and stone beads. Here we present the study of 57 stone beads from the site using qualitative and quantitative methods that demonstrate the presence of multiple stone ornament workshop traditions. Examination of perforations from beads and pendants made from regionally available raw materials of marble, nephrite, serpentine, and other undetermined stone have identified the use of metal drills with abrasives and diamond drills. These drilling techniques along with the distinctive shapes of some finely made beads, as well as the reworking of older broken beads suggests the presence of different scales and organization of local production in Southeast Asia. The different shapes and production processes of carnelian and banded agate beads also may represent various workshop traditions. Some of these latter beads may have originated in South Asia, while others may have been made in different regions of Southeast Asia. This study demonstrates that careful examination of ornament production techniques, and especially bead perforation technology, can be used to identify the presence of different workshop traditions allowing for more fine-grained consideration of inter- and intra-regional bead exchange networks in Southeast Asia. The presence of many semi-precious stone beads of different materials and having morphologically and technologically distinct features at Phromtin Tai demonstrate the active consumption of the beads by social elites at the site. These diversified and exotic status markers represent an intensification and acceleration of the economy and social complexity at Phromtin Tai.