Sensitivity Analysis of Transient Storage Parameters in Mathematical Modeling of Pollution Transport in Rivers Containing Storage Zone

Hydrologists studying rivers must determine the relative importance of in-river processes to understand the fate of pollutants. Storage processes are one of the most of this. Currently, the most reliable method for determining the importance of storage processes in the solute transfer is to estimate the stream-storage exchange coefficient (α) and the cross-sectional area ratio (AS/A) in the transient storage model (TSM) with tracer experiment data (Wallis and Manson, 2019). Calibrating the parameters depends on the reciprocal coverage between parameter effects on BTCs and the model's sensitivity to each parameter (Zaramella et al., 2016). Previous studies have quantified the sensitivity of the TSM in inverse modeling (Kelleher et al., 2013; Wlostowski et al., 2013). Due to tracer test data for these studies, their results cannot provide a comprehensive picture of the model behavior. In this study, using Monte Carlo-based methods, an attempt has been made to investigate the effect of different pollutant transfer circumstances in the river by defining a framework with Peclet and Damkohler numbers and pollutant injection time series on storage parameters sensitivity

Intracranial Blood Flow Velocity in Patients with β-Thalassemia Intermedia Using Transcranial Doppler Sonography: A Case-Control Study

Introduction. Patients with β-thalassemia intermedia have a higher incidence of thromboembolic events compared to the general population. Previous studies have shown that patients with sickle cell disease, who are also prone to ischemic events, have higher intracranial arterial blood flow velocities measured by transcranial Doppler sonography (TCD). The aim of this study is to evaluate intracranial arterial flow velocities in patients with β-thalassemia intermedia and compare the results with those found in healthy subjects. Methods. Sixty-four patients with β-thalassemia intermedia and 30 healthy subjects underwent transcranial Doppler sonography. Results. Significantly higher flow velocities were found in intracranial arteries of patients compared to controls (P = 0.001). Previously splenectomized patients with thrombocytosis showed higher flow velocities than nonsplenectomized patients without thrombosis. Conclusion. The increased flow velocities in patients with β-thalassemia intermedia may point to a higher risk of ischemic events. Preventive measures such as blood transfusion or antiplatelet treatment may be beneficial in these patients

In vivo reprogramming: A new approach for tissue repair in chronic diseases

Medical researchers and biologists have long been fascinated by the possibility of changing the identity of cells, a phenomenon known as cellular plasticity. Now, we know that differentiated cells can be experimentally coaxed to become pluripotent (cellular reprogramming). Recent studies have demonstrated that changes in cell identity are not limited to the laboratory, but also the tissue cells in live organisms are subjected to this process, too (endogenous cellular reprograming). Nowadays “reprogramming technology” has created new opportunities in understanding human chronic diseases, drug discovery, and regenerative medicine. This technology have enabled the generation of various specific cell types including cardiomyocytes, pancreatic beta cell, and neurons, from patient’s cells such as skin fibroblasts. Reprogramming technology provides a novel cell source for autologous cell transplantation. But, cell transplantation faces several difficult hurdles such as cell production and purification, long-term survival, and functional integration after transplantation. Recently, in vivo reprogramming, which uses endogenous cells for tissue repair, has emerged as a new approach to circumvent cell transplantation. Up till now, in vivo reprogramming has been practiced in the mouse pancreas, heart, brain, and spinal cord with various degrees of success. In this review, we summarize the progress made, therapeutic potentials, and the challenges ahead in this emerging research area

Microstructural refining during friction stir processing of SAF 2205 duplex stainless steel

Friction stir processing (FSP) was conducted on a SAF 2205 duplex stainless steel at advancing speed of 50 mm/min and rotational speed of 400 rpm.  Characterization of evolved material was studied using electron microscopy equipped with electron back scattered diffraction (EBSD) system. The results indicated that the severe plastic deformation and the heat generated during the FSP developed a very fine microstructure in the stir zone (SZ). It was found that the finest grains with average grain size less than 1 µm were formed in the bottom of the SZ where the material was more likely to receive the lowest temperature in both constituent phases of ferrite and austenite. Therefore, it can be inferred that the material in the bottom of the SZ was less affected from the heat generated by the shoulder. The presence of such severe deformation along with the elevated temperature during the welding procedure inside the SZ activates the occurrence of continuous dynamic recrystallization mechanism throughout the material which seems to be responsible for grain refinement. Moreover, 111 and 110 pole figures of both constituent phases demonstrated that the rotating tool broke the initial microstructure, modified the pre-existence rolling texture of the starting material, and introduced simple shear texture components into the SZ

In vivo reprogramming: A new approach for tissue repair in chronic diseases

Medical researchers and biologists have long been fascinated by the possibility of changing the identity of cells, a phenomenon known as cellular plasticity. Now, we know that differentiated cells can be experimentally coaxed to become pluripotent (cellular reprogramming). Recent studies have demonstrated that changes in cell identity are not limited to the laboratory, but also the tissue cells in live organisms are subjected to this process, too (endogenous cellular reprograming). Nowadays “reprogramming technology” has created new opportunities in understanding human chronic diseases, drug discovery, and regenerative medicine. This technology have enabled the generation of various specific cell types including cardiomyocytes, pancreatic beta cell, and neurons, from patient’s cells such as skin fibroblasts. Reprogramming technology provides a novel cell source for autologous cell transplantation. But, cell transplantation faces several difficult hurdles such as cell production and purification, long-term survival, and functional integration after transplantation. Recently, in vivo reprogramming, which uses endogenous cells for tissue repair, has emerged as a new approach to circumvent cell transplantation. Up till now, in vivo reprogramming has been practiced in the mouse pancreas, heart, brain, and spinal cord with various degrees of success. In this review, we summarize the progress made, therapeutic potentials, and the challenges ahead in this emerging research area

Cross-talks between the kidneys and the central nervous system in multiple sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease, which is considered as a common autoimmune disorder in young adults. A growing number of evidences indicated that the impairment in non-neural tissues plays a significant role in pathology of MS disease. There are bidirectional relationship, metabolic activities and functional similarity between central nervous system (CNS) and kidneys which suggest that kidney tissue may exert remarkable effects on some aspects of MS disorder and CNS impairment in these patients compels the kidney to respond to central inflammation. Recently, it has been well documented that hormonal secretion possesses the important role on CNS abnormalities. In this regard, due to the functional similarity and significant hormonal and non-hormonal relationship between CNS and kidneys, we hypothesized that kidneys exert significant effect on initiation, progression or amelioration of MS disease which might be regarded as potential therapeutic approach in the treatment of MS patients in the future

Causes and Results of Eye Removal Surgery in Yazd, Iran

Introduction: Removing eyes has different indications. We surveyed the causes and results of eye removal surgery in Yazd, Iran. Methods: We retrospectively reviewed the profile of 102 patients who had underwent eye removal surgery for any reason in the Shahid Sadoughi hospital during the last 10 years. The demographic characteristics, causes of enucleation, the interval between an accident and an eye surgery, and postoperative complications were analyzed. Results:  In 102 patients (males, 68.6% and females, 31.4%) most cases were laborers (21.6%).The two most common causes of eye enucleation were  trauma (60.9%) and painful blind eye (15.7%). Trauma was the most frequent cause in the age group of  ≤20 years old (78.9%) (P-value< 0.001). In 30.4% of the cases, our management was Sympathetic ophthalmia prevention. Conclusion: The first cause of eye removal surgery in our study was trauma, especially in the young men. To reduce the rate of this surgery, protective proceeding, early diagnosis, and treatment of many diseases will be useful

Paid internet advertising (PIA) and frequency of apps-buying decisions: Insights from the retail enterprises in an emerging market

Purpose: Despite the tremendous advancement of information technology worldwide, a few attempts have been made to uncover the effectiveness of paid internet advertising (PIA) on consumers buying decisions for retail enterprises in emerging markets. The purpose of this paper is to examine the structural relationships between consumer self-confidence, perceived intrusiveness, continuance search intention, attitude towards PIA and frequency of apps-buying decisions. Design/methodology/approach: A total number of 515 online questionnaires were obtained from a sample of experienced apps shoppers who were disposed to PIA, in order to evaluate the theoretical model. VB-SEM, which is a variance-based structural equation modelling technique, was applied to assess the measurement scales and structural relationship between exogenous and endogenous constructs. Findings: Overall, the structural results imply that the proposed model explains 0.738 per cent of variances in consumer’s continuance search intention and 0.756 per cent of the frequency of apps-buying decisions. The results support that consumer self-confidence positively influences attitude towards PIA, continuance search intention and frequency of apps-buying decisions; however, consumer self-confidence is negatively related to perceived intrusiveness. Similarly, attitude towards PIA is positively related to continuance search intention and frequency of apps-buying decision. Besides, perceived intrusiveness negatively influences attitude towards PIA, continuance search intention and frequency of apps-buying decisions. Finally, continuance search intention and the frequency of apps-buying decisions are positively related. Originality/value: Despite the fact that PIA and its utilisation has been a recent growing trend in managing retail enterprises worldwide, a few studies have been conducted on possible end results of PIA, including consumer continuous apps search intention and purchase decisions. © 2018, Emerald Publishing Limited

Explorative learning strategy and its impact on creativity and innovation: An empirical investigation among ICT-SMEs

Purpose: The purpose of this paper is to examine the structural relationships among explorative learning strategy, improvisational creativity, compositional creativity, and innovation in information and communication technology small- and medium-sized enterprises (ICT-SMEs). Design/methodology/approach: In total, 213 valid questionnaires from SMEs’ top management positions were evaluated to investigate the proposed model of the research empirically. As a methodological approach, partial least square (PLS) path modeling approach, a variance-based structural equation modeling was employed. Findings: The statistical results imply that explorative learning has a positive impact on improvisational creativity and innovation while improvisational creativity has a positive influence on compositional creativity and innovation as well. Compositional creativity and innovation are also positively associated. Surprisingly, improvisational creativity mediates the relationship between explorative learning and innovation. Furthermore, PLS-multi group analysis reveals that heterogeneity exists in the collected data and number of employees is a moderating variable. The results of the research indicate that companies with number of employees between 51 and 100 are more creative and innovative in comparison with other groups. On the other hand, the positive relationship between explorative learning and compositional creativity was not supported in this research. Originality/value: This study is one of the few research works in the realm of examining the structural relationship among explorative learning strategy, improvisational creativity, compositional creativity, and innovation in ICT-SMEs, regarding the number of employees as a moderating variable

Impact of exploitative learning strategy on Malaysian SMEs' creativity and innovation capabilities

Small and medium-sized enterprises (SMEs) can be considered as learning enterprises due to their competitive natures. The aim of the present study is to examine the notion of exploitative learning strategy, which is practised among Malaysian SMEs to determine to which extent it will result in creativity and innovation. A questionnaire was developed and was distributed among 1,850 SMEs online from which 206 surveys were thoroughly completed and returned. A variance-based structural equation modelling technique (VBSEM) was utilised to assess the measurement as well as the structural relationships for exogenous and endogenous constructs. Results of hypothesis testing indicate that the exploitative learning strategy has a significant, positive role in improvisational creativity, compositional creativity and innovation while its indirect effect on innovation capability is also significant through compositional creativity. This study also finds that the number of employees moderates the relationship between exploitative learning strategy, improvisational creativity and innovation in SMEs