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Repair offers significant time—cost savings and durability by reusing existing parts efficiently. Prior to implementation of repaired parts, it is crucial to clarify mechanical properties and deformation mechanisms to ensure proper performance. In this study, a repair deposition was performed on the groove of wrought stainless steel 316L using the same material powder. The repaired sample exhibited an excellent combination of ductility and strength (T.EL: 58%, YS: 407 MPa, UTS: 673 MPa) compared to the wrought counterpart. With heterogeneity in microstructure, the hetero-deformation-induced strengthening of the repaired sample resulted in a synergy of strength-ductility combinations.

Direct energy deposition (DED) has gained attention in the field of metal repair because of its ability to integrate additively deposited material with preexisting components. Having the beneficial aspects of depositing right material, DED is evaluated the best option for repair deposition. Machining grooves in damaged components is the common first to repair, which is necessary to remove cracked or damaged material and provide suitable geometry for deposition. Preprocessing as grooving is commonly applied to prevent the propagation cracks or tears. However, challenges such as dimensional error and crack induced by residual stress emerge owning to complex interactions between the DED parameters and groove geometry during repair deposition. This study investigates effective deposition strategies for repairing 316L stainless steel grooves with wall-angles of 90° and 135° by exploring the relationship between the repair integrity and parameters such as groove angles, laser energy input, and powder supply, all with reference to the underlying mechanism of metallurgical bonding in angled areas. Based thereon, a modified effective repair strategy is proposed, using enhanced dual laser power to address bonding issues in the angled areas. Samples repaired using this method exhibit a defect-free groove–deposit interface and a continuous columnar-grained microstructure with abrupt changes in grain size between the repaired area and groove. This microstructural heterogeneity results in an exceptional combination of strength and ductility when compared to the base material and samples repaired using a single laser strategy. The findings of this study provide insights into the optimization of DED strategies for achieving robust metallurgical bonding within grooves, thereby advancing technological maturity in the field of metal repair.

High-strength materials are essential for applications in the structural industry. However, their limited formability restricts broader industrial use. This study proposes a novel methodology to achieve an excellent combination of formability and strength. Surface heterostructuring through laser treatment induces local austenitization on the as-rolled martensitic stainless steel. The resultant bendability was significantly improved, enabling its bending to ∼180° folding while maintaining high tensile strength. Consequently, the present surface heterostructuring suggests achieving the superior combination of strength and formability by tailoring the microstructure specifically to forming. This surface heterostructuring will explore the empty area of the formability-strength relationship.

Heterostructured materials offer great promise as next-generation structural materials, providing excellent combinations of strength and elongation. However, the need for additional equipment for heterostructuring poses challenges for scalability. In this study, we propose a strategy to fabricate heterostructured materials using conventional cold-rolling, eliminating the need for additional pre- or post-treatments. This newly developed method refines only surface grains with shear stress induced by cold-rolling performed at a slight thickness reduction. The cold-rolled samples exhibited improved strengths at the expense of ductility compared to the as-received homogeneous sample, primarily attributed to the heterogeneous strengthening effect and the increased pre-existing dislocation densities. Depending on the cold-rolling process conditions, yield strength increased from 85.6 MPa to 138.6 MPa, and the corresponding elongation loss was 5.5% and 14.8%, respectively. The increase in yield strength of the cold-rolled samples at the same uniform elongation as the as-received sample, calculated using a trend line, was about 51.5 MPa. This proposed strategy has the potential to advance the industrialization of heterostructured materials by enabling large-scale fabrication using conventional processing equipment.

A heterostructuring strategy is an effective approach for abiding problems referred to as the strength-ductility trade-off. However, tailoring the heterostructure is an arduous problem. This work synthesized hierarchically heterogeneity by combining the eutectic high-entropy alloy (EHEA) and medium-entropy alloy powders through novel powder metallurgy-based severe plastic deformation (P-SPD). EHEA forms nano-scaled heterogeneity composed of FCC and B2, and the mixture of powder types forms micro-scale heterogeneity with hard and soft domains. This hierarchically heterogeneous microstructure leads to strong hetero-deformation-induced strengthening, achieving a yield strength of ∼1.5 GPa. The present P-SPD represents the feasibility of heterostructuring, aiding the development of HEAs.

The configurational design of heterostructures has received considerable attention to achieve a superior combination of strength and ductility. Although heterostructuring for enhanced tensile properties has been widely analyzed, studies on the effect of heterogeneity on sheet formability are still insufficient. Sheet metal formability is one of the most crucial factors for determining hetero-materials’ industrial utilization. To broaden the industrial applicability of heterostructured layered materials, investigating the effects of heterogeneity in the layered structure on formability is necessary. This study investigated the stretch formability of aluminum-steel-aluminum clad sheets using the Erichsen cupping test. The three-layered clad sheets showed additional hardening with a slight increase in ductility owing to hetero-deformation-induced hardening because the strain-hardening exponent has a linear relationship with stretchability or necking resistance. After necking, damage evolution owing to severe internal stress concentration led to delamination at the interface. Interestingly, delamination serves as a block to full cracking through the thickness during forming. This study contributes to the industrial applicability of heterogeneous structuring by elucidating the characteristics of heterogeneity and formability.

The advantages of heterostructured materials as structural materials include superior mechanical properties and the ability to tailor the strength-ductility combination via microstructure customization. To maximize heterostructure effects, this study combined direct energy deposition and ultrasonic nanocrystalline surface modification processes to create a CoCrFeMnNi equiatomic high-entropy alloy with multi-layered microstructures. The fabricated CoCrFeMnNi high-entropy alloy has a novel microstructure composed of multiple layers of repetitive microstructures with heterogeneity and demonstrates a remarkable synergetic strengthening effect in comparison to conventional heterogeneous materials. The outstanding mechanical properties derived from various hard and soft layer interfaces, as well as the effects of each layer and interface, were quantitatively analyzed using grain-scale digital image correlation technology. By combining the direct energy deposition and ultrasonic nanocrystalline surface modification processes, this study presents a method for fabricating a new class of heterostructured materials with multi-layered microstructure that exhibit deformation heterogeneity and grain size heterogeneity. The multi-layered microstructure with multiple heterogeneous boundaries breaks the conventional wisdom regarding heterostructured materials having only one or two heterogeneous interfaces.

Macroscopic and microscopic mechanical properties, and damage behaviors of materials should be evaluated through multi-scale investigations to allow for practical industrial applications and promote user safety. Clad metal, a type of heterostructured material, is one of the most promising advanced materials for commercialization. However, heterostructured materials (e.g., clad metals, multi-phase metals, and composite metals) are limited by the possible deterioration of their mechanical properties caused by the strain partitioning at the interface of dissimilar phases when heavily deformed. Therefore, quantitative analysis of multi-scale damage development is necessary for the beneficial future utilization of clad metals as well as structural materials that are currently used in the industry. In this study, the mechanical properties and damage behaviors of Al1050/low-carbon steel/Al1050 clad sheet at multiple scales were quantitatively analyzed using macro-scale digital image correlation (DIC) and micro-scale DIC techniques. The multi-scale investigation results will contribute to the improvement of the reliability of clad materials by quantitatively identifying their mechanical properties and damage behaviors on various scales, which will be beneficial for industrial applications.

Background: Treatment adherence is a vital aspect in the management of chronic diseases like leprosy; however, most studies on treatment adherence focus on patients. This study aims to examine the perceptions of healthcare providers on factors that can promote or prevent patients from adhering to treatment. Methods: We conducted three focus group discussions (FGDs) with healthcare providers who have at least one year experience in managing leprosy in three large leprosy case-holding hospitals in Metro Manila, Philippines. We audio-recorded, transcribed, translated the FGD proceedings, and analyzed the transcripts thematically to identify patient-intrinsic and patient-extrinsic enablers and barriers to treatment adherence of leprosy patients. Results: Patient-intrinsic motivators to complete treatment include innate desire to be cured, fear of infecting family and friends, fear of disability, good knowledge about the disease, need for medical clearance to be considered fit to work, and experiencing leprosy reactions. Patient-extrinsic motivators to complete treatment include free treatment, immediate and sufficient counselling, flexibility in treatment, follow-up and motivation of healthcare workers, and presence of Hansen’s Club and support groups. Patient-intrinsic barriers to good treatment adherence include distance between residence and hospital, financial and opportunity costs, adverse drug reactions, misconceptions about being cured, disabilities and presence of leprosy reactions, stubbornness and/or laziness, and undergoing clinical depression. Patient-extrinsic barriers to good treatment adherence include poor availability of MDT, transfer to other leprosy treatment facilities without informing current facility, and stigma. Conclusion: Healthcare providers perceive that patient-intrinsic and patient-extrinsic factors influence the treatment adherence of leprosy patients through different mechanisms. We highlight the role of healthcare provider attitudes, stigma, and support groups in promoting treatment adherence.

Background: Poor treatment adherence among leprosy patients contribute to relapse, development of antimicrobial resistance, and the eventual plateauing of the prevalence and incidence of leprosy not just in the Philippines, but also worldwide. For this reason, we aimed to identify the patterns and determinants affecting treatment completion and default among multibacillary leprosy patients. Methods: We conducted a retrospective cohort study involving three large hospitals in Metro Manila, Philippines. Patients who started the World Health Organization - Multiple Drug Therapy for multibacillary leprosy between January 1, 2007 and December 31, 2013 were included in the study. Selected socio-demographic and clinical data were abstracted from the patient treatment records. Survival analysis and proportional hazards regression were used to analyze the data. Results: Records of 1,034 patients with a total follow-up time of 12,287 person-months were included in the analysis. Most patients were male, younger than 45 years old, had an initial bacterial index between 1 and 4, and were residents of Metro Manila. Less than 20% had their treatment duration extended to more than 12 months. Treatment adherence of the patients was poor with less than 60% completing treatment. Most patients complete their treatment within 12 months, but treatment duration may be extended for up to three years. Patients who default from treatment usually do so a few months after initiating it. After adjusting for other variables, hospital, initial bacterial index, and non-extended treatment duration were associated with treatment completion. These factors, in addition to age, were also found to be associated with treatment default. Conclusion: This study provides quantitative evidence that there might be marked variations in how doctors in particular hospitals manage their patients, and these findings underscore the need to revisit and re-evaluate clinical practice guidelines to improve treatment outcomes and adherence.

Buddhist tantric practitioners embrace the liminal status of the human body to manifest divine identity. In piercing to the pith of human embodiment, the tantric practitioner reconfigures the shape and contours of his/her reality. This article investigates the evolution of one particular technique for piercing to the pith of the body on Tibetan soil, a ritual practice known as body mandala [lus dkyil Skt. deha-maṇḍala]. In particular, it uncovers a significant shift of emphasis in the application of the Guhyasamāja body mandala practice initiated by champions of the emerging Gandenpa [Dga’ ldan pa] or Gelukpa [Dge lugs pa] tradition of Tibetan Buddhism, Tsongkhapa (1357–1419) and Mkhas grub rje (1385–1438). This article reveals some of the radical implications of ritual exegesis, ranging from the socioreligious aspects of securing prestige for a tradition to the ultimate soteriological goals of modifying the boundaries between life and death and ordinary and enlightened embodiment.

Termination of the stem cells in the floral meristem (also known as floral determinacy) is critical for the reproductive success of plants, and the molecular activities regulating floral determinacy are precisely orchestrated during the course of floral development. In Arabidopsis thaliana, regulators of floral determinacy include several transcription factor genes, such as APETALA2 (AP2), AGAMOUS (AG), SUPERMAN (SUP), and CRABSCLAW (CRC), as well as a microRNA (miRNA), miR172, which targets AP2. How the transcription factor and miRNA genes are coordinately regulated to achieve floral determinacy is unknown. A mutation in POWERDRESS (PWR), a previously uncharacterized gene encoding a SANT-domain-containing protein, was isolated in this study as an enhancer of the weakly indeterminate ag-10 allele. PWR was found to promote the transcription of CRC, MIR172a, b, and c and/or enhance Pol II occupancy at their promoters, without affecting MIR172d or e. A mutation in mature miR172d was additionally found to enhance the determinacy defects of ag-10 in an AP2-dependent manner, providing direct evidence that miR172d is functional in repressing AP2 and thereby contributes to floral determinacy. Thus, while PWR promotes floral determinacy by enhancing the expression of three of the five MIR172 members as well as CRC, MIR172d, whose expression is PWR-independent, also functions in floral stem cell termination. Taken together, these findings demonstrate how transcriptional diversification and functional redundancy of a miRNA family along with PWR-mediated co-regulation of miRNA and transcription factor genes contribute to the robustness of the floral determinacy network.

Stem cells are crucial in morphogenesis in plants and animals. Much is known about the mechanisms that maintain stem cell fates or trigger their terminal differentiation. However, little is known about how developmental time impacts stem cell fates. Using Arabidopsis floral stem cells as a model, we show that stem cells can undergo precise temporal regulation governed by mechanisms that are distinct from, but integrated with, those that specify cell fates. We show that two microRNAs, miR172 and miR165/166, through targeting APETALA2 and type III homeodomain-leucine zipper (HD-Zip) genes, respectively, regulate the temporal program of floral stem cells. In particular, we reveal a role of the type III HD-Zip genes, previously known to specify lateral organ polarity, in stem cell termination. Both reduction in HD-Zip expression by over-expression of miR165/166 and mis-expression of HD-Zip genes by rendering them resistant to miR165/166 lead to prolonged floral stem cell activity, indicating that the expression of HD-Zip genes needs to be precisely controlled to achieve floral stem cell termination. We also show that both the ubiquitously expressed ARGONAUTE1 (AGO1) gene and its homolog AGO10, which exhibits highly restricted spatial expression patterns, are required to maintain the correct temporal program of floral stem cells. We provide evidence that AGO10, like AGO1, associates with miR172 and miR165/166 in vivo and exhibits "slicer" activity in vitro. Despite the common biological functions and similar biochemical activities, AGO1 and AGO10 exert different effects on miR165/166 in vivo. This work establishes a network of microRNAs and transcription factors governing the temporal program of floral stem cells and sheds light on the relationships among different AGO genes, which tend to exist in gene families in multicellular organisms.