High Velocity Impact Response and Damage Mechanism of an Aluminium/Glass-Carbon Fiber/Epoxy Composite Plate Reinforced with Graphene Nano-plates

Shayan Shahjouei,Mohammad Reza Barati,Mehdi Yarmohammad Tooski 한국섬유공학회 2021 Fibers and polymers Vol.22 No.2

The interface of fiber-polymer matrix has a critical role in controlling the mechanical features of polymercomposites. Most of the studies focused on the application of reduced graphene oxide in enhancing the interfacial propertiesof the composite. In this study, we focused on utilising the Graphene nano-plates (GNPs) with average diameter of 5-10 μm. The GNPs were assessed by different techniques of XRD and AFM. The GNPs incorporated into the epoxy matrix, and thenthe high velocity impact response was evaluated. The result of GNPs incorporation into the epoxy matrix showed that the0.3 wt.% GNPs incorporation into the glass fiber epoxy matrix and 0.9 wt.% GNPs incorporation into the glass-carbon fiber/epoxy were destructive on the absorption energy of the composite. The optimum concentration of the incorporated GNPshighly dependent upon the type of fiber in the matrix and the level of initial velocity in the impact test. Although the highconcentration of GNPs (up to 0.9 wt.%) dispersed at the interface of the glass fiber/epoxy resin can induce the high velocityimpact performance, but it resulted in the reduction of the impact performance of glass-carbon fiber/epoxy due to theagglomeration of the GNPs.

Comparative effects of systemic administration of levofloxacin and cephalexin on fracture healing in rats

Shayan Golestani,Arash Golestaneh,Atousa Aminzadeh Gohari 대한구강악안면외과학회 2022 대한구강악안면외과학회지 Vol.48 No.2

Objectives: This study aimed to compare the effects of systemic administration of levofloxacin or cephalexin on fracture healing in rats. Materials and Methods: In this animal study, tibial fractures not requiring fixation were artificially induced in 30 male Wistar albino rats using a 1.1 mm surgical bur. The rats were randomly divided into 6 groups (n=5). Groups 1 and 2 received daily subcutaneous saline injections. Groups 3 and 4 received subcutaneous injections of 25 mg/kg levofloxacin twice daily. Groups 5 and 6 received daily subcutaneous injections of 20 mg/kg cephalexin. The rats in Groups 1, 3, and 5 were sacrificed after 1 week, while the rats in Groups 2, 4, and 6 were sacrificed after 4 weeks. The score of fracture healing was determined through histological assessment of sections from the fracture site according to Perry and colleagues. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests. Results: The mean score of fracture healing at 4 weeks was significantly higher than that at 1 week in the saline, levofloxacin, and cephalexin groups (P<0.001). At 1 week, no significant difference was noted among the three groups of saline, levofloxacin, and cephalexin in the mean score of fracture healing (P=0.360). However, this difference was significant at 4 weeks (P=0.018), and the mean score in the saline group was significantly higher com-pared to that in the levofloxacin group (P=0.015). Conclusion: It is recommended not to prescribe levofloxacin for more than 1 week after surgical management of bone fractures due to its possible adverse effects on fracture healing.

Effect of Combined Herbal Capsule Menohelp on Hot Flashes and Night Sweats in Postmenopausal Women: A Single-Blind Randomized Controlled Trial

Arezoo Shayan,Seyedeh Zahra Masoumi,Farideh Kazemi,Khodayar Oshvandi 대한폐경학회 2020 대한폐경학회지 Vol.26 No.2

Objectives: Hot flashes and night sweats are the most common and annoying consequences of menopause. The present study aimed to investigate the effect of a combined herbal capsule (black cohosh, soy, potato, chaste tree, and burdock) on hot flashes and night sweats in postmenopausal women. Methods: The present study was a randomized clinical trial conducted on postmenopausal women who were referred to Hamadan health centers in 2018–2019. The patients were distributed randomly in two groups of 85 individuals using the permuted block technique. The intervention group received the Menohelp capsule 550 mg twice daily for eight weeks and those in the control group received placebo. Data was obtained using a demographic questionnaire and a night sweat checklist one week before and eight weeks after the intervention. Data analysis was done using Stata 13. Results: Data analysis revealed that means of hot flashes duration, frequency and intensity did not significantly decrease in the postintervention phase as compared to the pre-intervention phase in both the groups (P > 0.05). Comparative analyses of frequency and intensity of night sweats in the two groups revealed that both variables decreased after intervention with the Menohelp capsule (P < 0.05). Conclusions: This study revealed that combined herbal medicine (Menohelp) was effective in reducing the frequency and intensity of night sweats. Therefore, it can be used to reduce night sweats in postmenopausal women.

Emerging Challenges and Roles for Quantity Surveyors in the Construction Industry

Shadi Shayan,Ki Pyung Kim,Tony Ma,Rob Freda,Zhuoran Liu KINFORMS 2019 Management Review Vol.14 No.1

The current ever-changing environment of the construction industry demands Quantity Surveyors to update their knowledge and skills to cope with the changes. In order to provide insights for Quantity Surveyors to be able to manage a construction project productively and increase their ability in accordance with the current demand of the construction industry, this research conduct a questionnaire survey and interviews. As a result, the most critical challenges for Quantity Surveyors are a) Adopting new technologies such as BIM for their current practice, and b) Increasing their knowledge regarding sustainable attributes for a construction project. This research also disclosed that the expected emerging roles for Quantity Surveyors are a) Sustainable Advisory ability, and b) BIM ability for cost management. The research findings are expected to advise the current Quantity Surveyor and Quantity Surveying companies to prepare future competencies in accordance with the global trend.

Frequency of posttrauma complications during hospital admission and their association with Injury Severity Score

Dasdar Shayan,Yousefifard Mahmoud,Ranjbar Mehri Farhang,Forouzanfar Mehdi,Mazloom Hamid,Safari Saeed 대한응급의학회 2023 Clinical and Experimental Emergency Medicine Vol.10 No.4

Objective Multiple trauma is associated with a remarkable risk of in-hospital complications, which harm healthcare services and patients. This study aimed to assess the incidence of posttrauma complications, their relationship with poor outcomes, and the effect of the Injury Severity Score (ISS) on their occurrence.Methods This retrospective cohort study was conducted at a pair of trauma centers, between January 2020 and December 2022. All hospitalized adult patients with multiple trauma were included in this study. Multivariable logistic regression was used to identify factors related to posttrauma complications.Results Among 727 multiple trauma patients, 90 (12.4%) developed in-hospital complications. The most frequent complications were pneumonia (4.8%), atelectasis (3.7%), and superficial surgical site infection (2.5%). According to multivariable logistic regression, ISS, the length of stay in the intensive care unit (ICU), the length of stay in the hospital, and mortality were significantly associated with complications. The complication rate increased by 17% with every single-unit increase in ISS (adjusted odds ratio [OR], 1.17; 95% confidence interval [CI], 1.00–1.38). Per every 1-day increase in the ICU or hospital stay, the complication rate increased by 65% (adjusted OR, 1.65; 95% CI, 1.00–2.73) and 20% (adjusted OR, 1.20; 95% CI, 1.03–1.41), respectively. Posttrauma complications were also significantly more common in patients with mortality (adjusted OR, 163.30; 95% CI, 3.04–8,779.32). In multiple trauma patients with a higher ISS, the frequency, severity, and number of complications were significantly increased.Conclusion In-hospital complications in multiple trauma patients are frequent and associated with poor outcomes and mortality. ISS is an important factor associated with posttrauma complications.

Characterization and Performance of Ni-Based Catalyst with Hercynite Support in Methane Decomposition

( Siddiqui Shaikh Shayan ),( Hussain Sayed Sajid ),( Nodira Saidova ),임지선 한국공업화학회 2023 한국공업화학회 연구논문 초록집 Vol.2023 No.1

Effects of dissolving microneedle fabrication parameters on the activity of encapsulated lysozyme

Fakhraei Lahiji, Shayan,Jang, Yoojung,Ma, Yonghao,Dangol, Manita,Yang, Huisuk,Jang, Mingyu,Jung, Hyungil Elsevier 2018 European journal of pharmaceutical sciences Vol.117 No.-

<P><B>Abstract</B></P> <P>Dissolving microneedle (DMN) is referred to a microscale needle that encapsulates drug(s) within a biodegradable polymer matrix and delivers it into the skin in a minimally invasive manner. Although vast majority of studies have emphasized DMN as an efficient drug delivery system, the activity of DMN-encapsulated proteins or antigens can be significantly affected due to a series of thermal, physical and chemical stress factors during DMN fabrication process and storage period. The objective of this study is to evaluate the effects of DMN fabrication parameters including polymer type, polymer concentration, fabrication and storage temperature, and drying conditions on the activity of the encapsulated therapeutic proteins by employing lysozyme (LYS) as a model protein. Our results indicate that a combination of low temperature fabrication, mild drying condition, specific polymer concentration, and addition of protein stabilizer can maintain the activity of encapsulated LYS up to 99.8 ± 3.8%. Overall, findings of this study highlight the importance of optimizing DMN fabrication parameters and paves way for the commercialization of an efficient delivery system for therapeutics.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Transcutaneous implantation of valproic acid-encapsulated dissolving microneedles induces hair regrowth

Fakhraei Lahiji, Shayan,Seo, Seol Hwa,Kim, Suyong,Dangol, Manita,Shim, Jiyong,Li, Cheng Guo,Ma, Yonghao,Lee, Chisong,Kang, Geonwoo,Yang, Huisuk,Choi, Kang-Yell,Jung, Hyungil Elsevier 2018 Biomaterials Vol.167 No.-

<P><B>Abstract</B></P> <P>The interest in alternative material systems and delivery methods for treatment of androgenetic alopecia has been increasing in the recent decades. Topical application of valproic acid (VPA), an FDA-approved anticonvulsant drug, has been shown to effectively stimulate hair follicle (HF) regrowth by upregulating Wnt/β-catenin, a key pathway involved in initiation of HF development. Moreover, a majority of studies have suggested that cutaneous wound re-epithelialization is capable of inducing HF through Wnt/β-catenin pathway. Here, we report fabrication and evaluation of a novel VPA-encapsulating dissolving microneedle (DMN-VPA) that creates minimally invasive dermal micro-wounds upon application, significantly improving the VPA delivery efficiency. DMN-VPA not only delivers encapsulated VPA with higher accuracy than topical application, it also stimulates wound re-epithelialization signals involved in HF regrowth. Through a series of <I>in vivo</I> studies, we show that micro-wounding-mediated implantation of DMN-VPA upregulates expression of Wnt/β-catenin pathway, alkaline phosphatase, proliferating cell nuclear antigen, loricrin and HF stem cell markers, including keratin 15, and CD34 more effectively than topical application.</P>

Dynamic Scheduling of FMS Using a Fuzzy Logic Approach to Minimize Mean Flow Time

Srinoi, Pramot,Shayan, Ebrahim,Ghotb, Fatemeh Korean Institute of Industrial Engineers 2008 Industrial Engineeering & Management Systems Vol.7 No.1

This paper is concerned with scheduling in Flexible Manufacturing Systems (FMS) using a Fuzzy Logic (FL) approach. Four fuzzy input variables: machine allocated processing time, machine priority, machine available time and transportation priority are defined. The job priority is the output fuzzy variable, showing the priority status of a job to be selected for the next operation on a machine. The model will first select the machines and then assign operations based on a multi-criteria scheduling scheme. System/machine utilization, minimizing mean flow time and balancing machine usage will be covered. Experimental and comparative tests indicate the superiority of this fuzzy based scheduling model over the existing approaches.

Analytical Coexistence Benchmark for Assessing the Utmost Interference Tolerated by IEEE 802.20

Abdulla, Mouhamed,Shayan, Yousef R. Korea Information Processing Society 2011 Journal of information processing systems Vol.7 No.1

Whether it is crosstalk, harmonics, or in-band operation of wireless technologies, interference between a reference system and a host of offenders is virtually unavoidable. In past contributions, a benchmark has been established and considered for coexistence analysis with a number of technologies including FWA, UMTS, and WiMAX. However, the previously presented model does not take into account the mobility factor of the reference node in addition to a number of interdependent requirements regarding the link direction, channel state, data rate and system factors; hence limiting its applicability for the MBWA (IEEE 802.20) standard. Thus, over diverse modes, in this correspondence we analytically derived the greatest aggregate interference level tolerated for high-fidelity transmission tailored specifically for the MBWA standard. Our results, in the form of benchmark indicators, should be of particular interest to peers analyzing and researching RF coexistence scenarios with this new protocol.