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Analyzing the Environmental Consequences of Production Processes from a System of Systems Perspective : A Case of Gear Manufacturing in the Automotive Industry

Many research studies have been done to investigate different aspects of environmental challenges. In the product development context, there have been attempts to reduce the environmental impacts of associated activities including the production processes themselves. As a result, various technological improvements have been made and new production processes e.g. powder metallurgy technologies have

Comparing acquisition and operation life cycle costs of powder metallurgy and conventional wrought steel gear manufacturing techniques

The automotive industry has striven for fuel economy and resource efficiency through the deployment of powder metallurgy (PM) manufacturing processes for few decades. However, PM technology for transmission gears is currently only used at a small scale within the automotive industry. This is mainly due to: its shortcomings in material properties and performance gaps for final parts; lack of advanc

CPR a general Cost Performance Ratio in Manufacturing - A KPI for judgement of different technologies and development scenarios

Several parameters and variables affect the production cost and the company competitiveness. The manufacturing part cost is directly influenced by factors related to tools, workpiece materials, equipment, personnel, automation, etc. These factors also have a significant influence on the manufacturing efficiency and performance. The presented model determines the production performance with respectSeveral parameters and variables affect the production cost and the company competitiveness. The manufacturing part cost is directly influenced by factors related to tools, workpiece materials, equipment, personnel, automation, etc. These factors also have a significant influence on the manufacturing efficiency and performance. The presented model determines the production performance with respect

Simulation of nanometric cutting using molecular dynamics

The aim of this work is to perform molecular dynamic simulations of nanometric cutting on single crystal copper with a diamond tool in orderto investigate the dependence of crystallographic orientation and cutting speeds on the cutting forces, machined surface and temperature. It wasfound that the temperature in the substrate, locally and globally, increased for increasing velocity. A higher degre

Determining process parameters for successful material reclamation of lead-free brass chips using hot forging operations: Lubrication

When small and hollow components are being manufactured, it is not uncommon that a majority of the workpiece material is removed by machining. A demand for parts made with lead-free brass alloys can potentially increase the manufacturing cost and therefore it is necessary to investigate ways to increase the material utilization. As part of a more resource efficient production, a method for reusing

Dosimetric and Clinical Predictors for Acute and Late Gastrointestinal Toxicity Following Chemoradiotherapy of Locally Advanced Anal Cancer

Aims: To analyse dosimetric and clinical predictors for acute and late gastrointestinal toxicity following chemoradiotherapy of anal cancer. Materials and methods: Consecutive patients with locally advanced (T2 ≥4 cm – T4 or N+) anal cancer were selected from an institutional database (n = 114). All received intensity-modulated radiotherapy with concomitant 5-fluorouracil and mitomycin C. Gastroin

Multi-objective testing of different brass alloy components for DFM

This paper investigates the differences of leaded and low-lead brasses in terms of mechanical and thermal properties, machinability and product strength using physical testing and simulations. The information can be used in companies for Design for Manufacturability (DFM) while designing processes for lead free brass. The novelty of this research is to combine data from different testing methods t

Functional recovery of the germ line following splicing collapse

Splicing introns from precursor-messenger RNA (pre-mRNA) transcripts is essential for translating functional proteins. Here, we report that the previously uncharacterized Caenorhabditis elegans protein MOG-7 acts as a pre-mRNA splicing factor. Depleting MOG-7 from the C. elegans germ line causes intron retention in most germline-expressed genes, impeding the germ cell cycle, and causing defects in

Syndecan receptors : pericellular regulators in development and inflammatory disease

The syndecans are the major family of transmembrane proteoglycans,usually bearing multiple heparan sulfate chains. They are present onvirtually all nucleated cells of vertebrates and are also present in invertebrates, indicative of a long evolutionary history. Genetic models in bothvertebrates and invertebrates have shown that syndecans link to the actincytoskeleton and can fine-tune cell adhesion

Analytical and Experimental Determination of the Ra Surface Roughness during Turning

In this article an analytical equation for calculating the theoretical arithmetic mean surface roughness, Ra, in the case of turning using a tool with a circular nose radius is presented. The deviation that often occurs between the expected and the obtained surface roughness during these machining operations is investigated. Influence of the minimum chip thickness is discussed especially in regard

Syndecans in Inflammation at a Glance

Syndecans are transmembrane proteoglycans with heparan and chondroitin sulfate chains attached to their extracellular domain. Like many proteoglycans, they interact with a large number of ligands, such as growth factors, adhesion receptors, soluble small molecules, proteinases, and other extracellular matrix proteins to initiate downstream signaling pathways. Syndecans play a major role in inflamm

Glycan Mimetics from Natural Products : New Therapeutic Opportunities for Neurodegenerative Disease

Neurodegenerative diseases (NDs) affect millions of people worldwide. Characterized by the functional loss and death of neurons, NDs lead to symptoms (dementia and seizures) that affect the daily lives of patients. In spite of extensive research into NDs, the number of approved drugs for their treatment remains limited. There is therefore an urgent need to develop new approaches for the preve

Quantitative analysis of chip segmentation in machining using an automated image processing method

Analysis of chip formation is one of the most established and informative methods for description of the cutting process. A number of established techniques ranging from optical to electron microscopy have been developed for analysis of continuous chips. Yet, machining of difficult-to-cut materials is accompanied by segmented chip formation. This paper presents an original algorithm based on image

Interferon-β-induced miR-1 alleviates toxic protein accumulation by controlling autophagy

Appropriate regulation of autophagy is crucial for clearing toxic proteins from cells. Defective autophagy results in accumulation of toxic protein aggregates that detrimentally affect cellular function and organismal survival. Here, we report that the microRNA miR-1 regulates the autophagy pathway through conserved targeting of the orthologous Tre-2/Bub2/CDC16 (TBC) Rab GTPase-activating proteins

Calcium in Cell-Extracellular Matrix Interactions

In multicellular organisms, the cells are surrounded by persistent, dynamic extracellular matrix (ECM), the largest calcium reservoir in animals. ECM regulates several aspects of cell behavior including cell migration and adhesion, survival, gene expression and differentiation, thus playing a significant role in health and disease. Calcium is reported to be important in the assembly of ECM, where

Computational and Experimental Inverse Problem Approach for Determination of Time Dependency of Heat Flux in Metal Cutting

This study develops the method for solution of inverse heat conduction problem applied to metal cutting. The proposed method operates with a selection procedure involving iterative solutions of heat forward problem. In such formulation, it allows avoiding difficulties associated with ill-posed inverse problems inherent to conventional formulations. Inverse heat problem was transformed into constra

A Protein Disulfide Isomerase Controls Neuronal Migration through Regulation of Wnt Secretion

Appropriate Wnt morphogen secretion is required to control animal development and homeostasis. Although correct Wnt globular structure is essential for secretion, proteins that directly mediate Wnt folding and maturation remain uncharacterized. Here, we report that protein disulfide isomerase-1 (PDI-1), a protein-folding catalyst and chaperone, controls secretion of the Caenorhabditis elegans Wnt

Computational Analysis of the Caenorhabditis elegans Germline to Study the Distribution of Nuclei, Proteins, and the Cytoskeleton

The Caenorhabditis elegans (C. elegans) germline is used to study several biologically important processes including stem cell development, apoptosis, and chromosome dynamics. While the germline is an excellent model, the analysis is often two dimensional due to the time and labor required for three-dimensional analysis. Major readouts in such studies are the number/position of nuclei and protein