174 research outputs found

    Unveiling the relation between the challenges and benefits of Operational Excellence and Industry 4.0: A Hybrid Fuzzy Decision-Making Approach

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    Operational excellence (OpEx) is a direction toward learning and developing an excellent culture in all aspects of an organization. To reach this culture, revolutionizing activities using industry 4.0 (i4.0) technologies might be a significant empowering tool. This study aims to identify the challenges and benefits of both concepts and investigate their interrelationship to be considered in applying industry 4.0 technologies toward operational excellence. The challenges and benefits of OpEx and i4.0 are identified and finalized by reviewing the literature. The causal relations between the considered factors are extracted using the fuzzy DEMATEL (Decision Making Trial and Evaluation Laboratory) method. Then, the analytical network process (ANP) is applied to determine the importance and weight of the factors (challenges and benefits of OpEx and i4.0) according to the constructed network. The findings illustrated a strong network structure between the factors. First, the causal factors included OpEx and i4.0 challenges, while the OpEx challenges also affected the i4.0 challenges. Both group challenges had a significant effect on OpEx and i4.0 benefits. This means that challenges are the causal factors to be considered in the alignment of i4.0 toward OpEx. Among the OpEx challenges, lack of strategic planning and proper infrastructure were the main influential factors. In contrast, lack of government support and undeveloped business models were identified as the main challenges of i4.0. OpEx and i4.0 concepts are reviewed, and their pros and cons are studied. Previous studies determined an interaction among these concepts. However, from a practical viewpoint, the relation between the challenges and benefits of i4.0 and OpEx was studied for the first time for their alignment

    The effect of preventive, therapeutic and protective exercises on hippocampal memory mediators in stressed rats

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    Background: Exercise plays a significant role in learning and memory. The present study focuses on the hippocampal corticosterone (CORT), interleukin-1 beta(IL-1β), glucose, and brain derived neurotrophic factor (BDNF) levels in preventive, therapeutic, and protective exercises in stressful conditions. Methods: Forty male rats were randomly divided into four groups: the control group and the preventive, therapeutic, and protective exercise groups. The treadmill running was applied at a speed of 20-21m/min and a chronic stress of 6 hours/day for 21 days. Subsequently, the variables were measured in the hippocampus. Results: The findings revealed that the hippocampal CORT levels in the preventive exercise group had a significant enhancement compared to the control group. In the protective and particularly the therapeutic exercise groups, the hippocampal CORT levels declined. Furthermore, the hippocampal BDNF levels in the preventive and the therapeutic exercise groups indicated significantly decreased and increased, respectively, in comparison with the control group. In the preventive exercise group, however, the hippocampal glucose level turned out to be substantially higher than that in the control group. Conclusion: It appears that the therapeutic exercise group had the best exercise protocols for improving the hippocampal memory mediators in the stress conditions. By contrast, the preventive exercise group could not improve these mediators that had been altered by stress. It is suggested that exercise time, compared to stress, can be considered as a crucial factor in the responsiveness of memory mediators. � Penerbit Universiti Sains Malaysia, 2016

    Substitutional doping of Cu in diamond: Mott physics with pp orbitals

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    Discovery of superconductivity in the impurity band formed by heavy doping of boron into diamond (C:B) as well as doping of boron into silicon (Si:B) has provided a rout for the possibility of new families of superconducting materials. Motivated by the special role played by copper atoms in high temperature superconducting materials where essentially Cu dd orbitals are responsible for a variety of correlation induced phases, in this paper we investigate the effect of substitutional doping of Cu into diamond. Our extensive first principle calculations averaged over various geometries based on density functional theory, indicates the formation of a mid-gap band, which mainly arises from the t2gt_{2g} and 4p4p states of Cu. For impurity concentrations of more than 1\sim 1%, the effect of 2pbandsofneighboringcarbonatomscanbeignored.Basedonourdetailedanalysis,wesuggestatwobandmodelforthemidgapstatesconsistingofaquarterfilledholelike bands of neighboring carbon atoms can be ignored. Based on our detailed analysis, we suggest a two band model for the mid-gap states consisting of a quarter-filled hole like t_{2g}band,andahalffilledbandof band, and a half-filled band of 4pstates.IncreasingtheconcentrationoftheCuimpuritybeyond states. Increasing the concentration of the Cu impurity beyond \sim 5%, completely closes the spectral gap of the host diamond.Comment: 5 figure

    A sentiment analysis software framework for the support of business information architecture in the tourist sector

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    In recent years, the increased use of digital tools within the Peruvian tourism industry has created a corresponding increase in revenues. However, both factors have caused increased competition in the sector that in turn puts pressure on small and medium enterprises' (SME) revenues and profitability. This study aims to apply neural network based sentiment analysis on social networks to generate a new information search channel that provides a global understanding of user trends and preferences in the tourism sector. A working data-analysis framework will be developed and integrated with tools from the cloud to allow a visual assessment of high probability outcomes based on historical data, to help SMEs estimate the number of tourists arriving and places they want to visit, so that they can generate desirable travel packages in advance, reduce logistics costs, increase sales, and ultimately improve both quality and precision of customer service

    The optimal vitamin D cut-off value associated with hyperglycemia in an Iranian population

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    Background: Vitamin D deficiency may accelerate the risk of type 2 diabetes mellitus. The association of vitamin D with hyperglycemia may be influenced by lifestyle. Objective: To evaluate the relationship between vitamin D status and hyperglycemia among the workers� population. Methods: This was a medical records review of 7054 Iranian factory workers participating in an annual health check-up for employees. Of those, potential participants were included in this analysis if data for serum 25-hydroxyvitamin D 25(OH) D levels were also available. Results: Data of 429 male participants were used for this analysis. Of those, 61.07% had serum 25(OH)D concentrations lower than the sufficient level �20 ng/ml. Hyperglycemic participants had significantly lower 25(OH)D than those with normal fasting blood glucose (FBG). Regression analyses highlighted serum 25(OH)D as a significant determinant of hyperglycemia OR: 0.943(0.901, 988); p = 0.01. The association between 25(OH)D and FBG remained significant after adjustment for potential confounders (p = 0.008). Using the ROC analysis, the serum 25(OH)D value of 14.7 ng/ml was the optimal cut-off point to predict hyperglycemia in this population (sensitivity: 63.6%, specificity: 62.3%, p = 0.01). Conclusion: Our results revealed a considerable proportion of participants with serum 25(OH)D below the optimal level as well as a significant inverse association between vitamin D status and hyperglycemia among the factory workers. These findings highlight the importance of including the evaluation of vitamin D status as a part of annual health examinations for employees, and may help health policy- makers prevent or delay type 2 diabetes mellitus among the workers� population. © 2019, Springer Nature Switzerland AG

    The trend of changes in depression, anxiety and stress in men with lower limb trauma: A prospective study

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    Introduction: Activity restrictions can have potential impacts on the prevalence of mental disorders. However, in patients with lower limb traumas the problems and the physical disabilities are usually taken more into consideration than mental status, while they refer for further examinations. Therefore, this study is aimed to investigate the changes in the process of depression, anxiety and stress in men with lower limb traumas. Materials and Methods: In a prospective study the patients with lower limb traumas, who have been hospitalized in Amir Al-Mo�menin and Kowsar hospitals in Semnan since June 2012 to August 2015, were selected randomly and studied. The data was collected by demographic and incident questionnaire and depression, anxiety and stress questionnaire. At first the patients were asked to complete the questionnaires based on their psychological experience of one month prior to the trauma. Then same questionnaires were completed by the patients one and three months after the trauma. The data was analyzed using Friedman and Wilcoxon tests. Results: The data of 157 patients was analyzed. The results showed that there was a significant difference in the severity of depression disorders, anxiety and stress in three stages of the study (P0.05). Conclusion: The prevalence of depression, anxiety and stress is increased in people with lower limb traumas. Therefore it is recommended that the patients with lower limb traumas to be supported mentally, socially and economically. © 2016, Semnan University of Medical Sciences. All rights reserved

    The Nomogram of Clitoral Length and Width in Iranian Term and Preterm Neonates

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    Background and Objectives: Clitoromegaly is an important parameter in the evaluation of ambiguous genitalia in neonates, but the normative data for clitoral size in newborns have racial/ethnic differences. The present study aimed to determine clitoral length (CL) and clitoral width (CW) values and establish cutoff measurement to define clitoromegaly in both term and preterm Iranian neonates for the first time. Methods: A total number of 580 female newborn infants delivered at 28�42 weeks of gestation were enrolled in the study, and their CL and CW were measured on the first 72 h of birth. Data about birth weight (BW), body length (BL), and head circumference (HC) of newborns; mothers' age; and gestational age (GA) were recorded, too. Results were presented as mean ± standard deviation (SD) for quantitative variables and were summarized by frequency (percentage) for categorical variables. Backward stepwise regression analysis was used for prediction of CL and CW. Results: Among 580 Iranian female newborns studied, 187 were term neonates and the other 393 newborns were preterm. Mean ± SD values of CL were 6.11 ± 0.39 mm in term infants and 5.45 ± 0.64 mm in preterm infants (P < 0.001). Mean ± SD values of CW were 4.22 ± 0.43 in term infants and 3.68 ± 0.53 in preterm infants (P < 0.001). Regression analysis showed that CL was correlated with GA considered by last menstrual period, BL, BW, and HC; and CW was associated with GA, BL, and BW. Conclusion: This study suggests normative values (mean + 1, 2, and 3 SD) of CL and CW according to GA, which can be used as a reference for Middle East's newborns, especially Iranian newborn babies. © Copyright © 2020 Alaei, Rohani, Norouzi, Hematian Boroujeni, Tafreshi, Salehiniya and Soheilipour

    Devil's staircase transition of the electronic structures in CeSb

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    Solids with competing interactions often undergo complex phase transitions with a variety of long-periodic modulations. Among such transition, devil's staircase is the most complex phenomenon, and for it, CeSb is the most famous material, where a number of the distinct phases with long-periodic magnetostructures sequentially appear below the Neel temperature. An evolution of the low-energy electronic structure going through the devil's staircase is of special interest, which has, however, been elusive so far despite the 40-years of intense researches. Here we use bulk-sensitive angle-resolved photoemission spectroscopy and reveal the devil's staircase transition of the electronic structures. The magnetic reconstruction dramatically alters the band dispersions at each transition. We moreover find that the well-defined band picture largely collapses around the Fermi energy under the long-periodic modulation of the transitional phase, while it recovers at the transition into the lowest-temperature ground state. Our data provide the first direct evidence for a significant reorganization of the electronic structures and spectral functions occurring during the devil's staircase.Comment: 22 pages, 5 figure

    Intravascular Ultrasound for Assessment of Residual Coarctation of the Aorta after Balloon Angioplasty in Infants

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    Intravascular ultrasound (IVUS) has been introduced as an accurate and minimally invasive diagnostic technique for the assessment of vascular anatomy and its abnormalities. We believe that IVUS can be used for clarifying the reasons for failure of balloon angiography in infantile coarctation of the aorta (CoA), because post-balloon angioplasty tearing, intimal flap, thrombosis and pseudoaneurysm of the aorta can be evaluated by IVUS with greater sensitivity and specificity. We aimed to assess the outcome of balloon angioplasty of CoA using angiography as the gold standard and IVUS as a new method in infants, comparing the two techniques for the evaluation of the diameter and area of CoA segment pre- and post-procedure. This cross-sectional study was performed on 18 infants hospitalized with a final diagnosis of CoA. All the infants underwent angiography and were also assessed by IVUS to measure the preoperative and postoperative diameter of the narrow segment in the two anterior�posterior and lateral views. In assessment by IVUS, the mean diameter of the coarctation site increased from 2.10 ± 0.30 mm to 4.50 ± 0.94 mm (P &lt; 0.001). Similarly, the average minimum area of the coarctation level increased from 5.26 ± 1.50 mm2 to 13.77 ± 3.48 mm2 after angioplasty (P &lt; 0.001). Comparing these findings, angiography and IVUS showed a high level of agreement. In the assessment of a dissection flap, there was a high level of agreement between angioplasty and IVUS before the procedure, but IVUS had higher accuracy after the procedure. Our study showed that IVUS was more reliable than angiography in the assessment of residual coarctation. IVUS yielded high sensitivity (58.3) and specificity (100) for discriminating the presence and absence of residual coarctation as well as the need for repeating the procedure. The assessment of coarctation before and after angioplasty procedures in children is possible using the IVUS method, with high accuracy. IVUS can offer greater accuracy than angiography in the evaluation of the coarctation area, detecting tears, dissection and flaps, and assessment of residual coarctation. © 2021, Springer Science+Business Media, LLC, part of Springer Nature

    Intravascular Ultrasound for Assessment of Residual Coarctation of the Aorta after Balloon Angioplasty in Infants

    Get PDF
    Intravascular ultrasound (IVUS) has been introduced as an accurate and minimally invasive diagnostic technique for the assessment of vascular anatomy and its abnormalities. We believe that IVUS can be used for clarifying the reasons for failure of balloon angiography in infantile coarctation of the aorta (CoA), because post-balloon angioplasty tearing, intimal flap, thrombosis and pseudoaneurysm of the aorta can be evaluated by IVUS with greater sensitivity and specificity. We aimed to assess the outcome of balloon angioplasty of CoA using angiography as the gold standard and IVUS as a new method in infants, comparing the two techniques for the evaluation of the diameter and area of CoA segment pre- and post-procedure. This cross-sectional study was performed on 18 infants hospitalized with a final diagnosis of CoA. All the infants underwent angiography and were also assessed by IVUS to measure the preoperative and postoperative diameter of the narrow segment in the two anterior�posterior and lateral views. In assessment by IVUS, the mean diameter of the coarctation site increased from 2.10 ± 0.30 mm to 4.50 ± 0.94 mm (P &lt; 0.001). Similarly, the average minimum area of the coarctation level increased from 5.26 ± 1.50 mm2 to 13.77 ± 3.48 mm2 after angioplasty (P &lt; 0.001). Comparing these findings, angiography and IVUS showed a high level of agreement. In the assessment of a dissection flap, there was a high level of agreement between angioplasty and IVUS before the procedure, but IVUS had higher accuracy after the procedure. Our study showed that IVUS was more reliable than angiography in the assessment of residual coarctation. IVUS yielded high sensitivity (58.3) and specificity (100) for discriminating the presence and absence of residual coarctation as well as the need for repeating the procedure. The assessment of coarctation before and after angioplasty procedures in children is possible using the IVUS method, with high accuracy. IVUS can offer greater accuracy than angiography in the evaluation of the coarctation area, detecting tears, dissection and flaps, and assessment of residual coarctation. © 2021, Springer Science+Business Media, LLC, part of Springer Nature
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