A multi-objective evolutionary approach for integrated production-distribution planning problem in a supply chain network

Integrated production-distribution planning (PDP) is one of the most important approaches in supply chain networks. We consider a supply chain network (SCN) to consist of multi suppliers, plants, distribution centers (DCs), and retailers. A bi-objective mixed integer linear programming model for integrating production-distribution designed here aim to simultaneously minimize total net costs in supply chain and transfer time of products for retailers. From different terms of evolutionary computations, this paper proposes a Pareto-based meta-heuristic algorithm called multi-objective simulated annealing (MOSA) to solve the problem. To validate the results obtained, a popular algorithm namely non-dominated sorting genetic algorithm (NSGA-II) is utilized as well. Since the solution-quality of proposed meta-heuristic algorithm severely depends on their parameters, the Taguchi method is utilized to calibrate the parameters of the proposed algorithm. Finally, in order to prove the validity of the proposed model, a numerical example is solved and conclusions are discussed

An experimental investigation of a hybrid photovoltaic/thermoelectric system with nanofluid application

Improving photovoltaic efficiency is fundamental to the large scale utilization of solar energy and reduction of carbon emission. In this field, reducing the temperature of the Photovoltaic (PV) panel will increase its efficiency and power production. Utilizing hybrid photovoltaic/thermoelectric (PV/TE) systems is an effective way to simultaneously release the excess heat of the PV panel and use this heat to produce power. The cooling method used for the thermoelectric module (TEM) plays an important role in the system efficiency as well as the produced power. A new nanofluid-based cooling method for a hybrid photovoltaic/thermoelectric system is proposed in this work and compared with the conventional cooling methods experimentally. To this end, five different cooling methods were investigated experimentally, namely natural cooling, forced air cooling, water cooling, SiO2/water nanofluid cooling, and Fe3O4/water nanofluid cooling. The results showed the promise of SiO2/water nanofluid cooling, which yielded the highest power and efficiency, showing 54.29% and 3.35% improvement, while Fe3O4/water nanofluid cooling showed 52.40% and 3.13% improvement in power production and efficiency respectively, comparing with the natural cooling method

A reference human induced pluripotent stem cell line for large-scale collaborative studies.

Human induced pluripotent stem cell (iPSC) lines are a powerful tool for studying development and disease, but the considerable phenotypic variation between lines makes it challenging to replicate key findings and integrate data across research groups. To address this issue, we sub-cloned candidate human iPSC lines and deeply characterized their genetic properties using whole genome sequencing, their genomic stability upon CRISPR-Cas9-based gene editing, and their phenotypic properties including differentiation to commonly used cell types. These studies identified KOLF2.1J as an all-around well-performing iPSC line. We then shared KOLF2.1J with groups around the world who tested its performance in head-to-head comparisons with their own preferred iPSC lines across a diverse range of differentiation protocols and functional assays. On the strength of these findings, we have made KOLF2.1J and its gene-edited derivative clones readily accessible to promote the standardization required for large-scale collaborative science in the stem cell field

A reference human induced pluripotent stem cell line for large-scale collaborative studies

Human induced pluripotent stem cell (iPSC) lines are a powerful tool for studying development and disease, but the considerable phenotypic variation between lines makes it challenging to replicate key findings and integrate data across research groups. To address this issue, we sub-cloned candidate human iPSC lines and deeply characterized their genetic properties using whole genome sequencing, their genomic stability upon CRISPR-Cas9-based gene editing, and their phenotypic properties including differentiation to commonly used cell types. These studies identified KOLF2.1J as an all-around well-performing iPSC line. We then shared KOLF2.1J with groups around the world who tested its performance in head-to-head comparisons with their own preferred iPSC lines across a diverse range of differentiation protocols and functional assays. On the strength of these findings, we have made KOLF2.1J and its gene-edited derivative clones readily accessible to promote the standardization required for large-scale collaborative science in the stem cell field

Comparison of diagnostic accuracy of serologic test with histology for Helicobacter pylori in diabetic patients with dyspepsia

Background: Helicobacter pylori infection is a major cause of gastric diseases in humans that its rapid, simple and low cost diagnosis is important. Diabetes mellitus increases the risk of Helicobacter pylori infection. Objective: The aim of this study was to compare diagnostic accuracy of serologic test with histology for Helicobacter Pylori in diabetic patients with dyspepsia. Methods: This analytical study was conducted on 183 diabetic patients with dyspepsia referred to Imam Hossain hospital of Shahroud in 2014. All patients underwent endoscopy. Standard biopsy was performed as gold standard which included six gastric and duodenal samples. Simultaneously, blood samples were taken for serologic test. The presence of Helicobacter pylori was examined using Giemsa staining in histological study. Anti-Helicobacter pylori IgG was measured using ELISA in serological study. Sensitivity, specificity, and positive and negative predictive values were calculated. Data were analyzed using Chi-square test. Findings: Of 183, 104 patients (57.1%) were positive for Helicobacter pylori in serological study and 151 patients (82.5%) were positive in histological study. The sensitivity, specificity, positive predictive value and negative predictive value of serologic test for diagnosis of Helicobacter pylori were 64.2%, 78.1%, 93.3%, and 31.6%, respectively. IgG cut point for diagnosis of Helicobacter pylori was set to be 1.4 (sensitivity: 92.4% and specificity: 75.3%). Conclusion: The serologic test can be used as screening test for Helicobacter pylori in diabetic patients with regards to relatively high sensitivity and specificity as well as its simplicity, rapidity, and low price. Keywords: Helicobacter Pylori, Diabetes Mellitus, Serologic Tests, Histology, Sensitivity and Specificit

Presenting a bi-objective integrated production – distribution planning problem model in a multi echelon supply chain with considering service level

In this paper, a bi-objective integrated of production distribution planning problem model in a multi echelon supply chain is presented. This model is considered in a four echelon supply chain includes suppliers, manufactures, distribution centers and customers with several types of raw material and product in multi-time period. In addition to minimize the total cost of supply chain including transportation and supply of materials costs, preparation and production of products, inventory holding of materials and products in manufacture and distribution centers, transportation and purchase of products for distributors and customers, and backorder cost, the second objective is to decrease the transfer time of products in order to increasing the service level for customers. Two Pareto-based multi-objective meta-heuristic algorithms namely non-dominated sorting genetic algorithm (NSGA-II) and non-dominated ranking genetic algorithm (NRGA) are proposed to solve the model. Since the solution quality of all meta-heuristic algorithms severely depended on their parameters, Taghuchi method has been utilized to tune the parameters of algorithms. Finally, computational results obtained by implementing the algorithms on several problems of different sizes demonstrate the performance of proposed methodologies

Comparison of diagnostic accuracy of serologic test with histology for Helicobacter pylori in diabetic patients with dyspepsia

Background: Helicobacter pylori infection is a major cause of gastric diseases in humans that its rapid, simple and low cost diagnosis is important. Diabetes mellitus increases the risk of Helicobacter pylori infection. Objective: The aim of this study was to compare diagnostic accuracy of serologic test with histology for Helicobacter Pylori in diabetic patients with dyspepsia. Methods: This analytical study was conducted on 183 diabetic patients with dyspepsia referred to Imam Hossain hospital of Shahroud in 2014. All patients underwent endoscopy. Standard biopsy was performed as gold standard which included six gastric and duodenal samples. Simultaneously, blood samples were taken for serologic test. The presence of Helicobacter pylori was examined using Giemsa staining in histological study. Anti-Helicobacter pylori IgG was measured using ELISA in serological study. Sensitivity, specificity, and positive and negative predictive values were calculated. Data were analyzed using Chi-square test. Findings: Of 183, 104 patients (57.1%) were positive for Helicobacter pylori in serological study and 151 patients (82.5%) were positive in histological study. The sensitivity, specificity, positive predictive value and negative predictive value of serologic test for diagnosis of Helicobacter pylori were 64.2%, 78.1%, 93.3%, and 31.6%, respectively. IgG cut point for diagnosis of Helicobacter pylori was set to be 1.4 (sensitivity: 92.4% and specificity: 75.3%). Conclusion: The serologic test can be used as screening test for Helicobacter pylori in diabetic patients with regards to relatively high sensitivity and specificity as well as its simplicity, rapidity, and low price

High-throughput generation of midbrain dopaminergic neuron organoids from reporter human pluripotent stem cells

Summary: Here, we describe a high-throughput 3D differentiation protocol for deriving midbrain dopaminergic neurons from human pluripotent stem cells. The use of organoids has become prevalent in disease modeling, but there is a high demand for more homogeneous cultures. Our approach is advantageous for large-scale production of uniform midbrain organoids that can be maintained in diverse formats, and our reporters allow for sorting of dopaminergic neurons. The maturing long-term organoid cultures can be used as a model for the entire midbrain.For complete details on the use and execution of this protocol, please refer to Ahfeldt et al. (2020)