Preliminary Studies Research Articles

Lipidomics and Metabolomics in Infant Atopic Dermatitis: What's the Correlation with Early Nutrition?

To date, the complex picture of atopic dermatitis (AD) has not yet been fully clarified, despite the important prevalence of this disease in the pediatric population (20%) and the possibility of persistence into adulthood, with important implications for the quality of life of those affected, as well as significant social and financial costs. The most recent scientific evidence suggests a new interpretation of AD, highlighting the important role of the environment, particularly that of nutrition in the early stages of development. In fact, the new indications seem to point out the harmful effect of elimination diets, except in rare cases, the uselessness of chrono-insertions during complementary feeding and some benefits, albeit weak, of breastfeeding in those at greater risk. In this context, metabolomics and lipidomics can be necessary for a more in-depth knowledge of the complex metabolic network underlying this pathology. In fact, an alteration of the metabolic contents in children with AD has been highlighted, especially in correlation to the intestinal microbiota. While preliminary lipidomic studies showed the usefulness of a more in-depth knowledge of the alterations of the skin barrier to improve the development of baby skin care products. Therefore, investigating the response of different allergic phenotypes could be useful for better patient management and understanding, thus providing an early intervention on dysbiosis necessary to regulate the immune response from the earliest stages of development.

Drug Repurposing for Thioredoxin Interacting Protein Through Molecular Networking, Pharmacophore Modelling, and Molecular Docking Approaches

Background: Diabetes Mellitus (DM) has emerged as one of the major causes behind global all-cause mortality between the age group of 20-79 years. Thioredoxin Interacting Protein (TXNIP) is a naturally occurring protein that primarily acts by binding to TRX protein, thereby inhibiting its ability to maintain the cellular reduced environment and subsequent oxidative stress, which leads to dysfunctional insulin production and pancreatic islet beta cell apoptosis. Objective: By inhibiting the levels of TXNIP, a search for new molecules was carried out by employing an in-silico approach. Methods: Molecular networking study was carried out using Cytoscape, wherein previously FDAapproved drugs were screened to check their ability to interact with TXNIP. This provided 14 drug molecules, which along with 11 previously obtained drug molecules that inhibit TXNIP, were subjected to pharmacophore generation. A pharmacophore was generated using the PharmaGist web server, which when visualised showed two hydrogen bond acceptors and one aromatic ring. Based on the generated pharmacophore model, we carried out virtual screening using ZINCPharmer. A total of 116 HITs were generated based on this pharmacophore model. We then subjected the 116 molecules to Molecular Docking against TXNIP (PDB: 4GEI) by using PyRx and the standard molecules, metformin and rosiglitazone. Results: Compared to the standard, we found 10 molecules that had a better binding affinity towards TXNIP. These 10 molecules were further taken for ADMET studies. From this, all 10 compounds showed good significant ADMET properties. Conclusion: From the preliminary studies, these 10 molecules showed good activity in the reversal of diabetes mellitus by reducing the levels of TXNIP.

Status of Preliminary Design Studies for the Three Superferric 30$^\circ$ Bending Magnets for the Energy Buncher of FAIR

Status of Preliminary Design Studies for the Three Superferric 30$^\circ$ Bending Magnets for the Energy Buncher of FAIR

Cobalt‐Catalyzed Enantioselective Reductive α‐Chloro‐Carbonyl Addition of Ketimine to Construct the β‐Tertiary Amino Acid Analogues

Abstractβ‐Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt‐catalyzed enantioselective reductive addition reaction of ketimine using α‐chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched β‐quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky‐type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late‐stage modification of drug candidates.

Cobalt-Catalyzed Enantioselective Reductive α-Chloro-Carbonyl Addition of Ketimine to Construct the β-Tertiary Amino Acid Analogues.

β-Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt-catalyzed enantioselective reductive addition reaction of ketimine using α-chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched β-quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky-type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late-stage modification of drug candidates.

Transformation of Bima local wisdom values through social studies e-book media

The development of postmodern-era technology in the world of education is increasingly sophisticated, thus impacting the character of students and their social environment. Technological progress negatively affects the lives of today's generation. When misuse of technology is widespread, it is imperative to strengthen cultural and religious filtration. So that the influence of globalization on technological development can be minimized. So as not to damage the cultural values and morality of students as the next generation of the nation. This study aims to explain the importance of transforming the values of Bima's local wisdom "Nggusu Waru" through the media of social studies e-books. The results and conclusions of this study are efforts to develop students' social character that require teacher collaboration, supervision, and optimal parental attention so that their interest in learning is higher and minimizes deviant behavior. This research method uses research and development design. At the stage of preliminary studies with models developed by Borg and Gall. Through several stages of research, information gathering, development of initial forms of products, and initial field testing. In this step, data is collected through interviews, observation and documentation. The data is analyzed to find out some of its weaknesses and shortcomings.

Cultural intermediary in higher education based on ethical relation

<span lang="EN-US">Preliminary studies on cultural intermediaries focused on social classes that mediate the production and consumption of culture. Therefore, this study determined the importance of the cultural intermediaries of migrant worker university students who popularize the values of higher education for the working class. Habitus and replication of meaning were used as analytical tools, with an alternative perspective proposed on cultural intermediaries using an ethical approach. The results showed that the cultural intermediary based on ethical relationships produces a new individual involvement of marginalized groups. Meanwhile, community relations with a similar social context are strengthened, enabling individuals to combine their allegiances and continuously generate values to suit certain social situations.</span>

Algal growth inhibition test with TEMPO-oxidized cellulose nanofibers

Ecotoxicity data on cellulose nanofibers (CNFs) are limited despite their wide potential applications prospects, such as structural and packaging materials, filters, coatings, foods, and cosmetics. In this study, toxicity tests of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized CNFs (TEMPO-CNFs), which are one of the major CNF products commercially available in Japan, on the green alga Raphidocelis subcapitata were conducted. As nanomaterials are considered difficult-to-test substances, the Organisation for Economic Co-operation and Development has released a guidance document that provides considerations regarding ecotoxicity tests of nanomaterials. In the algal growth inhibition tests of TEMPO-CNFs, there were specific issues to be examined, including the effects of medium components on the characteristics of TEMPO-CNFs, CNF interference with algal density measurements, algal interference with CNF measurements, and the effects of ion concentration changes in the test medium by the addition of CNFs on algal growth. To examine these issues, we conducted preliminary studies and established a suitable test method for algal growth inhibition tests of TEMPO-CNFs. We confirmed that the components in the medium for algal growth inhibition tests had negligible effects on the characteristics (zeta-potential, viscosity, and morphology) and concentration stability of TEMPO-CNFs and that in vitro and in vivo fluorescence measurements were applicable for estimating the algal densities, without interference by TEMPO-CNFs. In contrast, we observed that the grown algae interfered with the CNF concentration measurements. Therefore, we established a method to correct the measured CNF concentrations by estimating the algal contribution. Furthermore, we found that the nutrient salt concentrations in the medium changed due to interactions with CNFs; however, this change did not affect algal growth. Based on the results of the preliminary studies, algal growth inhibition tests of TEMPO-CNFs were conducted using in vitro and in vivo fluorescence measurements, along with measurements of CNFs and ion concentrations in the test dispersions. The test results showed that no growth inhibition was observed on growth rate or yield even at the maximum CNF concentration of 100 mg/L, suggesting that the ecological effect of TEMPO-CNFs on algae was relatively low. The results of this study will be valuable for conducting ecotoxicity assessments on additional CNFs and comparable nanomaterials in future studies.

A Metallocene Bis(phosphoranocarbene) of Uranium and a Probe of Its Reactivity with Alcohols.

The addition of 2 equiv of the phosphaylide H2C═PPh3 to the dimethyl uranium metallocene Cp*2UMe2 (Cp* = η5-C5Me5) in toluene with gentle heating at 40 °C generates the phosphorano-stabilized bis(carbene) Cp*2U[C(H)PPh3]2 (1) in good yield. Characterization of 1 by X-ray crystallographic analysis reveals two short uranium-carbon bonds, ranging from 2.301(5) to 2.322(5) Å, consistent with the presence of U═C carbene-type bonds. Monitoring the reaction by NMR spectroscopy suggests that it proceeds through the intermediate formation of the methyl carbene complex Cp*2U[C(H)PPh3](Me) (1Int); however, prolonged heating of these solutions leads to the ortho-cyclometalated carbene species Cp*2U{κ2-[C(H)PPh2(C6H4)]} (2) via intramolecular C-H activation. Rapid conversion from 1 to 2 occurs within hours upon heating its toluene solutions to 100 °C. Preliminary reactivity studies of 1 show that it readily reacts with alcohols, such as HODipp (Dipp = 2,6-diisopropylphenyl) and HOC(CF3)3, to give the mixed carbene alkoxide compounds Cp*2U[C(H)PPh3](OR) (R = Dipp (4Dipp), C(CF3)3 (5CF3)). In one case, the reaction of 1 with HODipp in the presence of adventitious water led to the formation of a few crystals of the terminal U(IV) oxo complex, [Ph3PCH3][Cp*2U(O)(ODipp)] (3oxo). The isolation of 1 marks the first instance of an unchelated, heteroatom-stabilized bis(carbene) complex of uranium that also provides an entryway to the synthesis of its monocarbene derivatives through protonolysis.

Construction of Si-Stereogenic Silanols by Palladium-Catalyzed Enantioselective C-H Alkenylation.

The construction of silicon-stereogenic silanols via Pd-catalyzed intermolecular C-H alkenylation with the assistance of a commercially available L-pyroglutamic acid has been realized for the first time. Employing oxime ether as the directing group, silicon-stereogenic silanol derivatives could be readily prepared with excellent enantioselectivities, featuring a broad substrate scope and good functional group tolerance. Moreover, parallel kinetic resolution with unsymmetric substrates further highlighted the generality of this protocol. Mechanistic studies indicate that L-pyroglutamic acid could stabilize the Pd catalyst and provide excellent chiral induction. Preliminary computational studies unveil the origin of the enantioselectivity in the C-H bond activation step.

Discovery of novel biphenyl-sulfonamide analogues as NLRP3 inflammasome inhibitors

The aberrant activation of NLRP3 inflammasome has been observed in various human diseases. Targeting the NLRP3 protein with small molecule inhibitors shows immense potential as an effective strategy for disease intervention. Herein, a series of novel biphenyl-sulfonamide NLRP3 inflammasome inhibitors were designed and synthesized. The representative compound H28 was identified as potent and specific NLRP3 inflammasome inhibitor with IC50 values of 0.57 μM. Preliminary mechanistic studies have revealed that compound H28 exhibits direct binding to the NLRP3 protein (KD: 1.15 μM), effectively inhibiting the assembly and activation of the NLRP3 inflammasome. The results in a mouse acute peritonitis model revealed that H28 effectively inhibit the NLRP3 inflammasome pathway, demonstrating their anti-inflammatory properties. Our findings strongly support the further development of H28 as potential lead compound for treating NLRP3-related diseases.

Analysis of the Harmonious Development of the National Tourism Strategic Area and Tourism Master Plan

This article examines the harmony or suitability between the National Tourism Strategic Area Document (KSPN) and the Tourism Master Plan (RIP). The successful development of the tourism industry in development is required to have a common perception between the central government and local governments. The author pays special attention to these two documents for comparison and validation. This study aims to determine harmony, suitability, and similarity to obtain results to be concluded as recommendations. Literature study research with a qualitative approach uses a two-phase research design with preliminary studies and case studies. The results of this study indicate that the harmony and suitability of KSPN and RIP are harmonious and appropriate, but several indicators must be explained so that a common perception can be formed. Furthermore, the research results can be used by the central and regional governments in developing tourism areas with the spirit of sustainable tourism development.
 Keywords: harmony, tourism, KSPN, RIP

Development of an Automated Feeding System for Hydroponic Plant Nutrition Using Arduino Uno

Hydroponic farming has been a promising alternative to traditional farming, but providing plants with proper and consistent nutrition remains challenging. The issue in the research is the inaccuracy of the nutrients provided to the plants, resulting in growth that does not meet the expectations. This study aims to develop an automated nutrition system for hydroponic farming using Arduino Uno and total dissolved solids (TDS) sensors. In conducting this research, the study began with a preliminary exploration, followed by the design and integration process. Subsequently, testing and experiments were conducted on a small scale. Preliminary studies were conducted to understand existing hydroponic practices and challenges in manually supplying nutrients. The design of an automation system with Arduino Uno and a TDS sensor is made to control nutrition automatically. Automation systems are tested and calibrated to ensure accuracy and proper response. Implementation on a small scale was done with a test group and a control group in hydroponics. Growth and yield data were collected and analyzed. The results showed that the automated system provided precise and consistent nutrition, increasing plant growth and yields compared to manual methods. This research makes a scientific contribution to developing sustainable and efficient agriculture. In conclusion, nutrition automation using Arduino Uno and TDS sensors is an effective solution to increase the efficiency and productivity of hydroponic farming.
 Keywords: hydroponics, automation, plant nutrition, Arduino Uno TDS sensor

The beneficial role of probiotics in colorectal cancer development and their prospects for application

Colorectal cancer (CRC) constitutes a significant global health concern, with its development closely associated with factors like diet, lifestyle, and imbalances in the gut microbiome. Probiotics, defined as beneficial microorganisms, have garnered substantial attention as a potential strategy for preventing and treating colorectal cancer. This paper explores the multifaceted role of probiotics in maintaining gut microbiota balance, regulating metabolites, and influencing the development of colorectal cancer. Probiotics function by competitively inhibiting harmful bacteria, producing cancer-fighting metabolites, such as short-chain fatty acids, and engaging in immunomodulatory mechanisms. While evidence from animal models and preliminary human studies suggests their potential in reducing the risk of colorectal cancer, further research is necessary to ascertain the optimal strains, dosages, and mechanisms in clinical trials. Simultaneously, probiotics are expected to serve as adjuvant therapies to enhance the effectiveness of colorectal cancer treatment. This paper sheds light on the evolving prospects of probiotics in colorectal cancer prevention and treatment, introducing new possibilities in the battle against this malignancy.

PENGARUH PEMBERIAN REWARDS DAN LINGKUNGAN KERJA TERHADAP PRESTASI KERJA KARYAWAN DI RSI MUHAMMADIYAH KENDAL

Work performance is the result of the quality and quantity achieved by an employee in their duties performing. Accomplishments can be achieved by increasing the satisfaction that can be realized giving Rewards proportionally and fair and to create a conducive working environment. Harmonious relationship that exists between a leader-employee is also needed among employees with one another to create a conducive working environment. The results of preliminary studies on Muhammadiyah Islamic Hospital of Kendal seen a lot of indiscipline and delay the return of earlier of employees and the number continues to increase. This research was quantitative descriptive with cross sectional research planning. Research populations were employees / workers of Muhammadiyah Islamic Hospital of Kendal. The sampling technique in this research is using proportions stratified random sampling with the number of sample as much as 137 people. Retrieval of data using questionnaires. Analysis of data using multiple linear regression analysis. There is an effect of giving rewards to employees' achievement of Muhammadiyah Islamic Hospital of Kendal (p<0,05). There is an influence of work environment of employees' achievement on Muhammadiyah Islamic Hospital of Kendal (p<0,05). There is an effect of giving rewards and working environment of employees' achievement on Muhammadiyah Islamic Hospital of Kendal.

Synthesis of N-Difluoromethyl Carbonyl Compounds from N-Difluoromethylcarbamoyl Fluorides.

Fluorinated small molecules are commonly used in functional small-molecule chemistry, and N-difluoromethyl (N-CF2H) compounds are particularly intriguing due to their unique and unexplored physiochemical properties. However, despite limited progress, a general methodological approach to the synthesis of N-CF2H compounds remains elusive. Here, guided by computation, we present a simple and practical protocol to access N-CF2H amides and related carbonyl derivatives. The protocol involves a one-pot conversion of thioformamides through desulfurization-fluorination and acylation, providing N-difluoromethylcarbamoyl fluoride building blocks that can be further diversified to a variety of unexplored N-CF2H carbonyl compounds with rich functionality. Additionally, preliminary studies on their properties and stability showcased their potential application in pharmaceuticals and agrochemicals.

Preparation and Preliminary Structure-Activity Relationship Studies of Schwarzinicine A Analogs as Vasorelaxant Agents.

Schwarzinicines A-D, a series of alkaloids recently discovered from Ficus schwarzii, exhibit pronounced vasorelaxant activity in rat isolated aorta. Building on this finding, a concise synthesis of schwarzinicines A and B has been reported, allowing further investigations into their biological properties. Herein, a preliminary exploration of the chemical space surrounding the structure of schwarzinicine A (1) was carried out aiming to identify structural features that are essential for vasorelaxant activity. A total of 57 analogs were synthesized and tested for vasorelaxant activity in rat isolated aorta. Both efficacy (Emax) and potency (EC50) of these analogs were compared. In addition to identifying structural features that are required for activity or associated with potency enhancement effect, four analogs showed significant potency improvements of up to 40.2-fold when compared to 1. Molecular dynamics simulation of a tetrameric 44-bound transient receptor potential canonical-6 (TRPC6) protein indicated that 44 could potentially form important interactions with the residues Glu509, Asp530, Lys748, Arg758, and Tyr521. These results may serve as a foundation for guiding further structural optimization of the schwarzinicine A scaffold, aiming to discover even more potent analogs.

Abstract A010: Prostate-specific membrane antigen use in glioma management: past, present, and future

Abstract Introduction: Prostate-Specific Membrane Antigen (PSMA) is a type II membrane-bound zinc metallopeptidase expressed in various tissues, including the prostate, renal tubular epithelium, small and large intestinal mucosa, and brain. It plays a role in cell proliferation pathways and folate and glutamate metabolism. PSMA has been utilized for imaging and treatment of prostate cancer and is also expressed in solid tumor neovasculature of other cancers. Gliomas, which are central nervous system neoplasms of glial tissue, represent a challenging group of tumors with limited treatment options due to their invasive nature. PSMA's ability to internalize and location makes it a promising diagnostic and therapeutic target for gliomas. This review synthesizes the literature surrounding the use of PSMA in gliomas to inform current and future directions of study. Methods: A review of the literature was conducted using PubMed and Scopus databases in June 2023. Seventy-one relevant studies, including histopathological, imaging, and therapeutic investigations, were identified. These publications were categorized by year of publication to analyze the evolution of PSMA research in glioma management. Additionally, clinicaltrials.gov was searched for ongoing clinical trials involving PSMA and gliomas. Results: Histopathological studies have demonstrated PSMA's high expression in glioma vasculature, particularly in glioblastoma (GBM), a high-grade glioma (HGG). Studies have investigated PSMA's role in tumor metabolism and its interplay with other tumor markers. Some research suggests that high PSMA expression in GBM endothelium may promote angiogenesis and correlates with poor prognosis. PSMA PET imaging has shown promise in diagnosing and differentiating HGGs and low-grade gliomas (LGGs). Studies have reported high sensitivity and diagnostic accuracy of PSMA PET for HGGs, making it a potentially useful screening tool for radioligand therapy patient selection. Mouse models have also been employed to evaluate the utility of PSMA PET imaging in GBM, with some studies suggesting its application in defining non-enhancing portions of tumors and recurrence volume. PSMA-targeted therapies, particularly PSMA-targeted radiotherapy using radionuclide agents like 177Lu-PSMA-617, have been explored for the treatment of gliomas. Case reports and preliminary studies have demonstrated potential efficacy and tumor response to such therapies, warranting further investigation. Conclusion: The evolving literature indicates that PSMA holds promise as a valuable tool in the diagnosis, prognosis, and treatment of gliomas. Studies have highlighted PSMA PET imaging's high diagnostic accuracy and its potential in patient selection for targeted therapies. However, more research is needed to fully understand the role of PSMA in glioma behavior and to optimize treatment strategies. Ongoing clinical trials and future investigations will further our knowledge of PSMA's potential in managing gliomas and improving patient outcomes. Citation Format: Joshua D. McBriar, Neeva Shafiian, Steven Scharf, A. Gabriella Wernicke. Prostate-specific membrane antigen use in glioma management: past, present, and future [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr A010.

Abstract B082: A pro-tumorigenic, aged microenvironment may aid in worsened disease progression in an HGSOC model

Abstract Over 70% of HGSOC patients are diagnosed after 55 and the average patient succumbs to disease at 70 years old. Despite this, most ovarian cancer research, and cancer studies generally, utilize young mice that are mimetic of human teenagers and/or do not investigate age as a variable despite it being the top cancer risk factor. An improved understanding of how age affects HGSOC progression may enable development of alternative treatment strategies aimed at intercepting metastasis and preventing cancer cells from establishing in the peritoneum. Our preliminary studies show tumor burden and disease severity are significantly higher in aged versus young animals. We developed an epithelial cell line derived from C57Bl/6 oviducts and used CRISPR-Cas9 genome editing to develop a syngeneic tumorigenic line harboring Trp53, Pten, and Brca2 deletions. After intraperitoneal injection into 6-week and 14-month-old immunocompetent C57Bl/6 mice, we observed a stark increase in tumor burden in aged mice. Furthermore, older mice died at a faster rate; all aged mice succumbed to disease within 1-month of inoculation compared to young mice surviving up to 3 months. Total RNA-sequencing of tumors harvested from aged and young mice is ongoing. Characterization of the tumor-naïve peritoneal compartment revealed the aged microenvironment to be highly inflammatory. When assessed via cytokine array, peritoneal fluid of aged mice had higher concentrations of inflammatory markers including soluble TNF receptor-1 (sTNFR-1), L-selectin, and VCAM-1. Flow cytometry of peritoneal lavage indicated an over 2-fold increase in the number CD45+ cells present in the peritoneal cavity, coinciding with cytokine array results. Within this population, there was nearly complete depletion of macrophage and neutrophil populations and a significant increase in B cells and CD4+ and CD8+ T cells. The percentage of PD-1+ CD8+ cells also increased. In addition to increased signs of inflammation, a significantly higher concentration of insulin-like growth factor-1 (IGF-I) and higher concentrations of the associated IGF binding proteins -3 and -6 were found in peritoneal fluid of aged mice. In addition, during tissue collection, organs of the aged mice were found to be much larger than young mice, a common effect of elevated IGF-I; aged omentum weighed 2-4 times that of young. Notably, IGF-I is known to inhibit apoptosis and promote proliferation and increased IGF-I is correlated with increased risk of breast, prostate, and lung cancer. A drastic difference in disease severity occurs when identical cancer cells are injected into 6-week and 14-month-old mice. To identify possible microenvironmental differences in the two populations, a broad panel of cytokines was assessed, and immune populations were quantified in pre-cancerous mice. Overall, multiple pro-inflammatory markers and the number of lymphocytes were upregulated in the aged peritoneal cavity, and markers of immune fatigue were present. Further work is aimed at identifying immune cell state via further cytometry and sequencing. Citation Format: Katherine A. Cummins, Ronny I. Drapkin, Matthew Knarr. A pro-tumorigenic, aged microenvironment may aid in worsened disease progression in an HGSOC model [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr B082.

Residual Stress Engineering for Wire Drawing of Austenitic Stainless Steel X5CrNi18-10 by Variation in Die Geometries-Effect of Drawing Speed and Process Temperature.

As a result of conventional wire-forming processes, the residual stress distribution in wires is frequently unfavorable for subsequent forming processes such as bending operations. High tensile residual stresses typically occur in the near-surface region of the wires and can limit further application and processability of the semi-finished products. This paper presents an approach for tailoring the residual stress distribution by modifying the forming process, especially with regard to the die geometry and the influence of the drawing velocity as well as the wire temperature. The aim is to mitigate the near-surface tensile residual stresses induced by the drawing process. Preliminary studies have shown that modifications in the forming zone of the dies have a significant impact on the plastic strain and deformation direction, and the approach can be applied to effectively reduce the process-induced near-surface residual stress distributions without affecting the diameter of the product geometry. In this first approach, the process variant using three different drawing die geometries was established for the metastable austenitic stainless steel X5CrNi18-10 (1.4301) using slow (20 mm/s) and fast (2000 mm/s) drawing velocities. The residual stress depth distributions were determined by means of incremental hole drilling. Complementary X-ray stress analysis was carried out to analyze the phase-specific residual stresses since strain-induced martensitic transformations occurred close to the surface as a consequence of the shear deformation and the frictional loading. This paper describes the setup of the drawing tools as well as the results of the experimental tests.